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Should Magnetic Resonance Angiography Be Used for Screening of Intracranial Aneurysm in Adults with Sickle Cell Disease? J Clin Med 2022; 11:jcm11247463. [PMID: 36556079 PMCID: PMC9786262 DOI: 10.3390/jcm11247463] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2022] [Revised: 12/10/2022] [Accepted: 12/14/2022] [Indexed: 12/23/2022] Open
Abstract
Magnetic resonance imaging (MRI) is used in patients with sickle cell disease (SCD) to detect silent cerebral infarcts. MR angiography (MRA) can identify arterial stenoses and intracranial aneurysms (ICANs) associated with SCD. In this study, we aimed to estimate the prevalence of ICANs in asymptomatic adult patients with SCD referred from the SCD clinic for routine screening by MRI/MRA using a 3T-MRI scanner. Findings were independently reviewed by two neuroradiologists. Between 2016 and 2020, 245 asymptomatic adults with SCD were stratified according to genotype (SS/S-β0thalassemia and SC/Sβ+). ICANs were found in 27 patients (11%; 0.95 CI: 8-16%). ICANs were more frequent in SS/S-β0thalassemia patients (20/118 or 17%; 0.95 CI: 11-25%) than in SC/βb+ patients (7/127 or 6%; 0.95 CI: 2-11%; p = 0.007). Individuals with SCD (particularly SS/S-β0thalassemia) have a higher prevalence of ICANs than the general population. We believe that MRA should be considered in the current American Society of Hematology guidelines, which already contain a recommendation for MRI at least once in adult SCD patients. However, the clinical significance of preventive treatment of unruptured aneurysms remains controversial.
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2
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Wang J, Ti L, Sun X, Yang R, Zhang N, Sun K. DSA Image Analysis of Clinical Features and Nursing Care of Cerebral Aneurysm Patients Based on the Deep Learning Algorithm. SCANNING 2022; 2022:8485651. [PMID: 36034470 PMCID: PMC9392628 DOI: 10.1155/2022/8485651] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/10/2022] [Revised: 07/27/2022] [Accepted: 08/03/2022] [Indexed: 06/15/2023]
Abstract
OBJECTIVE A deep learning algorithm was developed for automatic detection and localization of intracranial aneurysms in DSA, and its clinical characteristics were analyzed, and targeted nursing measures were formulated. METHODS Using a retrospective multicenter study method based on radiology reports, DSA images of aneurysms were randomly divided into 75 cases in the training set, 20 cases in the internal test set, and 35 cases in the external test set. Using a computer-aided detection method based on the three-dimensional U-Net (3D U-Net), after preprocessing DSA images, automatic segmentation of intracranial blood vessels is performed to obtain regions of interest, and based on the segmentation results, physicians' annotations are introduced. The 3D U-Net network model is trained and adjusted, and the obtained model is used to automatically detect the cerebral aneurysm area. RESULTS Fivefold cross-validation was used for the training set and the internal test set, and a sensitivity of (94.4 ± 1.1)% was obtained. Automatic detection of aneurysms was performed on the external test set, and the average false positive rate was 0.86 FPs/case (false positives/case). The resulting sensitivity was 82.9%. The classification comparison of external test sets showed that the sensitivity of the method for detecting aneurysms with sizes of 5.00~<10.00 mm and ≥10.00 mm (88.2% and 100.0%) was higher than that for aneurysms with sizes of <3.00 mm and 3.00~<5.00 mm (50.0% and 72.7%). The sensitivity of patients aged 50-60 years and >60 years (90.0% and 87.5%) was higher than that of patients aged <50 years (66.7%), and there was little difference between different genders (84.6% in males and 81.8% in females). CONCLUSION The deep learning algorithm has high diagnostic performance in detecting intracranial aneurysms, which is verified by external datasets.
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Affiliation(s)
- Jian Wang
- The First Hospital of Hebei Medical University, Shijiazhuang, Hebei 050031, China
| | - Lin Ti
- The First Hospital of Hebei Medical University, Shijiazhuang, Hebei 050031, China
| | - Xiaorui Sun
- The First Hospital of Hebei Medical University, Shijiazhuang, Hebei 050031, China
| | - Ruping Yang
- The First Hospital of Hebei Medical University, Shijiazhuang, Hebei 050031, China
| | - Nafei Zhang
- The First Hospital of Hebei Medical University, Shijiazhuang, Hebei 050031, China
| | - Kejuan Sun
- The First Hospital of Hebei Medical University, Shijiazhuang, Hebei 050031, China
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3
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Chen G, Meng C, Ruoyu D, Dongdong W, Liqin Y, Wei X, Yuxin L, Daoying G. An Automatic Detection Method Of Cerebral Aneurysms In Time-Of-Flight Magnetic Resonance Angiography Images Based On Attention 3D U-Net. COMPUTER METHODS AND PROGRAMS IN BIOMEDICINE 2022; 225:106998. [PMID: 35939977 DOI: 10.1016/j.cmpb.2022.106998] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2021] [Revised: 01/23/2022] [Accepted: 06/30/2022] [Indexed: 01/10/2023]
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4
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Vornetti G, Bartiromo F, Toni F, Dall’Olio M, Cirillo M, Speier P, Princiotta C, Schmidt M, Tonon C, Zacà D, Lodi R, Cirillo L. Follow-Up Assessment of Intracranial Aneurysms Treated with Endovascular Coiling: Comparison of Compressed Sensing and Parallel Imaging Time-of-Flight Magnetic Resonance Angiography. Tomography 2022; 8:1608-1617. [PMID: 35736881 PMCID: PMC9227072 DOI: 10.3390/tomography8030133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2022] [Revised: 06/08/2022] [Accepted: 06/14/2022] [Indexed: 11/24/2022] Open
Abstract
The aim of our study was to compare compressed sensing (CS) time-of-flight (TOF) magnetic resonance angiography (MRA) with parallel imaging (PI) TOF MRA in the evaluation of patients with intracranial aneurysms treated with coil embolization or stent-assisted coiling. We enrolled 22 patients who underwent follow-up imaging after intracranial aneurysm coil embolization. All patients underwent both PI TOF and CS TOF MRA during the same examination. Image evaluation aimed to compare the performance of CS to PI TOF MRA in determining the degree of aneurysm occlusion, as well as the depiction of parent vessel and vessels adjacent to the aneurysm dome. The reference standard for the evaluation of aneurysm occlusion was PI TOF MRA. The inter-modality agreement between CS and PI TOF MRA in the evaluation of aneurysm occlusion was almost perfect (κ = 0.98, p < 0.001) and the overall inter-rater agreement was substantial (κ = 0.70, p < 0.001). The visualization of aneurysm parent vessel in CS TOF images compared with PI TOF images was evaluated to be better in 11.4%, equal in 86.4%, and worse in 2.3%. CS TOF MRA, with almost 70% scan time reduction with respect to PI TOF MRA, yields comparable results for assessing the occlusion status of coiled intracranial aneurysms. Short scan times increase patient comfort, reduce the risk of motion artifacts, and increase patient throughput, with a resulting reduction in costs. CS TOF MRA may therefore be a potential replacement for PI TOF MRA as a first-line follow-up examination in patients with intracranial aneurysms treated with coil embolization.
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Affiliation(s)
- Gianfranco Vornetti
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC di Neuroradiologia, 40139 Bologna, Italy; (G.V.);; (M.D.); (C.P.)
| | - Fiorina Bartiromo
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Programma Neuroimmagini Funzionali e Molecolari, 40139 Bologna, Italy; (F.B.); (C.T.); (R.L.)
| | - Francesco Toni
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Programma di Neuroradiologia con Tecniche ad Elevata Complessità, 40139 Bologna, Italy;
| | - Massimo Dall’Olio
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC di Neuroradiologia, 40139 Bologna, Italy; (G.V.);; (M.D.); (C.P.)
| | - Mario Cirillo
- Dipartimento di Scienze Mediche e Chirurgiche Avanzate, Università della Campania "Luigi Vanvitelli", 81100 Napoli, Italy;
| | - Peter Speier
- Siemens Healthineers, 91052 Erlangen, Germany; (P.S.); (M.S.); (D.Z.)
| | - Ciro Princiotta
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC di Neuroradiologia, 40139 Bologna, Italy; (G.V.);; (M.D.); (C.P.)
| | - Michaela Schmidt
- Siemens Healthineers, 91052 Erlangen, Germany; (P.S.); (M.S.); (D.Z.)
| | - Caterina Tonon
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Programma Neuroimmagini Funzionali e Molecolari, 40139 Bologna, Italy; (F.B.); (C.T.); (R.L.)
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, 40138 Bologna, Italy
| | - Domenico Zacà
- Siemens Healthineers, 91052 Erlangen, Germany; (P.S.); (M.S.); (D.Z.)
| | - Raffaele Lodi
- IRCCS Istituto delle Scienze Neurologiche di Bologna, Programma Neuroimmagini Funzionali e Molecolari, 40139 Bologna, Italy; (F.B.); (C.T.); (R.L.)
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, 40138 Bologna, Italy
| | - Luigi Cirillo
- IRCCS Istituto delle Scienze Neurologiche di Bologna, UOC di Neuroradiologia, 40139 Bologna, Italy; (G.V.);; (M.D.); (C.P.)
- Dipartimento di Scienze Biomediche e Neuromotorie, Università di Bologna, 40138 Bologna, Italy
- Correspondence:
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Thamburaj K, Zammar S, Tsay A, Tun K, Simon S, Kalapos P, Fiorelli M, Cockroft K. Magnetic Resonance Angiography after Flow Diversion: The use of complementary MRA techniques to monitor aneurysm occlusion as well as device and arterial branch patency after flow diverter placement. World Neurosurg 2022; 162:e147-e155. [PMID: 35248768 DOI: 10.1016/j.wneu.2022.02.096] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2021] [Revised: 02/22/2022] [Accepted: 02/23/2022] [Indexed: 11/28/2022]
Abstract
BACKGROUND Few studies have been performed to evaluate flow diversion with MRA. They have shown better success for MRA to assess the aneurysm response but limited success for the stent patency. Further, the patency of arterial branches on MRA remains to be explored. METHODS 31 consecutive cases of carotid aneurysms treated with flow diversion were retrospectively evaluated with noncontrast time of flight (TOF), contrast enhanced TOF (CTOF) and cine MRA (TWIST) independently by two investigators for aneurysm occlusion, stent patency and arterial branch patency. DSA served as the gold standard technique. RESULTS There were 6 males and 25 females in the age range of years (mean ±SD). Stent patency, aneurysm occlusion and branch patency, mostly revealed substantial to perfect interobserver agreement (k >0.60). The sensitivity, specificity, positive and negative predictive values for the stent patency on source images of TOF were 0.99,0.84, 0.42 and 0.99 and on CTOF were 0.99, 0.89, 0.50 and 0.99 respectively.Sensitivity for the aneurysm response on the three MRAs ranged from 0.88 to 0.93,specificity from 0.64 to 0.75, positive predictive value from 0.69 to 0.79 and negative predictive value from 0.86 to 0.90. Sensitivity for the arterial branch patency among the three MRAs, ranged from 0.55 to 0.93, specificity from 0.61 to 0.68, positive predictive value from 0.79 to 0.93 and negative predictive value from 0.22 to 0.90. CONCLUSIONS Aneurysm occlusion, stent patency and arterial branch patency in flow diversion can be successfully evaluated with the combination of three MRA techniques.
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Affiliation(s)
| | - Samer Zammar
- Department of Neurosurgery PennState Health Milton S Hershey Medical Center and PennState College of Medicine PennState University, Hershey, PA 17033
| | - Annie Tsay
- Internal Medicine Cambridge Health Alliance, 1493 Cambridge Street, Cambridge, MA 02139
| | - Kyaw Tun
- Pennstate Health Department of Radiology, Community Practice Division
| | - Scott Simon
- Department of Neurosurgery PennState Health Milton S Hershey Medical Center and PennState College of Medicine PennState University, Hershey, PA 17033
| | | | - Marco Fiorelli
- Department of Human Neurosciences, Sapienza University of Rome, Viale del Universita, 30, 00185, Rome, Italy
| | - Kevin Cockroft
- Department of Neurosurgery PennState Health Milton S Hershey Medical Center and PennState College of Medicine PennState University, Hershey, PA 17033
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Chen PR, Lopez-Rivera V, Conner CR, Sanzgiri A, Sheth SA, Erkmen K, Kim DH, Day AL. Utility of skull X-rays in identifying recurrence of coiled cerebral aneurysms. J Cerebrovasc Endovasc Neurosurg 2021; 23:108-116. [PMID: 33902273 PMCID: PMC8256019 DOI: 10.7461/jcen.2021.e2020.10.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2020] [Accepted: 01/15/2021] [Indexed: 11/23/2022] Open
Abstract
OBJECTIVE A high rate of cerebral aneurysm recurrence following endovascular coiling has prompted the use of digital subtraction angiography (DSA) for interval follow-up. However, the utility of skull x-rays as an alternative screening method for aneurysm recurrence is unproperly characterized. METHODS Retrospective review of a prospective registry of ruptured and unruptured cerebral aneurysms. Anteroposterior and lateral skull x-rays were obtained immediately at the end of the procedure and at 6-month follow-up. Aneurysm recurrence was defined by comparing post-procedure and 6-month DSA imaging. A true positive was defined as a change in coil mass morphology on at least one projection with aneurysm recurrence on DSA, and a true negative defined as a stable coil mass on both projections and no recurrence on DSA. Receiver operating characteristic area under the curve (AUC) statistics was used to assess the performance of skull x-rays in identifying aneurysm recurrence. RESULTS A total of 118 cerebral aneurysms were evaluated with DSA imaging and skull x-rays. A change in coil mass morphology on one projection of skull x-rays correctly detected all true recurrences with a sensitivity of 100% (95% confidence interval [CI], 91-100%). Skull x-rays failed to identify a stable aneurysm coil mass in 15 cases, with a specificity of 79% (68-88%). Skull x-rays performed with AUC 0.8958 (95% CI, 0.8490-0.9431) in identifying aneurysm recurrence. CONCLUSIONS The findings of our study suggest that skull x-rays may represent a lowcost, non-invasive screening tool to rule out aneurysm recurrence, which can potentially aid in decreasing the utilization of DSA in the follow-up of patients with coiled cerebral aneurysms.
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Affiliation(s)
- Peng Roc Chen
- Department of Neurosurgery, University of Texas McGovern Medical School, Houston, TX, USA
| | - Victor Lopez-Rivera
- Department of Neurology, University of Texas McGovern Medical School, Houston, TX, USA
| | - Christopher R Conner
- Department of Neurosurgery, University of Texas McGovern Medical School, Houston, TX, USA
| | - Aditya Sanzgiri
- Department of Neurosurgery, University of Texas McGovern Medical School, Houston, TX, USA
| | - Sunil A Sheth
- Department of Neurology, University of Texas McGovern Medical School, Houston, TX, USA
| | - Kadir Erkmen
- Department of Neurosurgery, Temple University, Philadelphia, PA, USA
| | - Dong H Kim
- Department of Neurosurgery, University of Texas McGovern Medical School, Houston, TX, USA
| | - Arthur L Day
- Department of Neurosurgery, University of Texas McGovern Medical School, Houston, TX, USA
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Patzig M, Forbrig R, Gruber M, Liebig T, Dorn F. The clinical value of ceMRA versus DSA for follow-up of intracranial aneurysms treated by coil embolization: an assessment of occlusion classifications and impact on treatment decisions. Eur Radiol 2020; 31:4104-4113. [PMID: 33221944 DOI: 10.1007/s00330-020-07492-3] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2020] [Revised: 09/10/2020] [Accepted: 11/10/2020] [Indexed: 11/26/2022]
Abstract
OBJECTIVE The aim of this study was a detailed analysis of the value of contrast-enhanced magnetic resonance angiography (ceMRA) compared to digital subtraction angiography (DSA) for follow-up imaging of intracranial aneurysms treated by coil embolization. METHODS Patients with coiled aneurysms and follow-up exams including both DSA and 3 T ceMRA were retrospectively identified. In blinded readings, both modalities were graded according to the modified Raymond-Roy classification (MRRC) and the Meyers scale. Additionally, readers were asked to make a decision regarding retreatment/follow-up based on the respective imaging findings. RESULTS The study comprised 92 patients harboring 102 coiled aneurysms. There was good intermethod agreement of DSA and ceMRA concerning both the MRRC (κ = 0.64) and the Meyers scale (κ = 0.74). Agreement regarding occlusion of < 90% of the aneurysm (Meyers grade ≥ 2) was very good (κ = 0.87). Regarding the detection of a remnant with contrast between the coil mass and the aneurysm wall (MRRC IIIb), there were 12 discrepant findings and agreement was good (κ = 0.70). Comparing treatment/follow-up decisions, the two methods agreed very well (κ = 0.92). In seven patients with discrepant treatment decisions, the authors concurred with DSA in four cases and with ceMRA in three cases when evaluating both modalities together. Interval aneurysm growth was found in more cases with ceMRA (n = 19) than with DSA (n = 16). CONCLUSIONS CeMRA is very unlikely to miss a relevant aneurysm remnant and thus could be suitable as the primary follow-up method. In case of remnant growth or recurrence, however, additional DSA might be required to guide treatment decisions. KEY POINTS • There is high accordance between ceMRA and DSA regarding the evaluation of intracranial aneurysms treated by endovascular coil embolization, but closer analysis also revealed relevant differences. • CeMRA could be suitable as the primary follow-up imaging modality, potentially eliminating the need for routine DSA. • DSA will still be required in case of aneurysm remnant growth or recurrence as detected by ceMRA.
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Affiliation(s)
- Maximilian Patzig
- Institute of Diagnostic and Interventional Neuroradiology, University Hospital, LMU Munich, Marchioninistr. 15, D-81377, Munich, Germany.
| | - Robert Forbrig
- Institute of Diagnostic and Interventional Neuroradiology, University Hospital, LMU Munich, Marchioninistr. 15, D-81377, Munich, Germany
| | - Margaretha Gruber
- Institute of Diagnostic and Interventional Neuroradiology, University Hospital, LMU Munich, Marchioninistr. 15, D-81377, Munich, Germany
| | - Thomas Liebig
- Institute of Diagnostic and Interventional Neuroradiology, University Hospital, LMU Munich, Marchioninistr. 15, D-81377, Munich, Germany
| | - Franziska Dorn
- Institute of Diagnostic and Interventional Neuroradiology, University Hospital, LMU Munich, Marchioninistr. 15, D-81377, Munich, Germany
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8
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Greve T, Sollmann N, Hock A, Zimmer C, Kirschke JS. Novel Ultrafast Spiral Head MR Angiography Compared to Standard MR and CT Angiography. J Neuroimaging 2020; 31:45-56. [PMID: 33118692 DOI: 10.1111/jon.12791] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2020] [Revised: 09/10/2020] [Accepted: 09/14/2020] [Indexed: 12/13/2022] Open
Abstract
BACKGROUND AND PURPOSE Intracranial vessel imaging by time-of-flight MR angiography (TOF-MRA) is one of the most frequently performed investigations in clinical neuroradiology. Particularly in the acute setting, fast imaging is needed for diagnostics, with a sequence ideally depicting even small vessels. The purpose of this study was to compare image and diagnostic quality of a novel ultrashort TOF-MRA sequence accelerated by spiral imaging (TOF-Spiral-short) to a standard TOF-MRA sequence accelerated by compressed sensing (TOF-CS) and to CT angiography (CTA). METHODS Forty-one patients (36.6% showing vessel pathologies) who had undergone TOF-CS (acquisition duration: 4 minutes 8 seconds), TOF-Spiral-short (acquisition duration: 51 seconds; spiral imaging [accelerating factor 1.3], decreased field of view [accelerating factor 1.2], and increased voxel size [accelerating factor 3.3]), and CTA were retrospectively evaluated. Assessment of image quality, diagnostic confidence, and quantification of stenosis or aneurysm diameter were performed by two readers. RESULTS Image quality at the skull base was slightly reduced with TOF-Spiral-short compared to CTA and TOF-CS (P < .05). Delineation of small intracranial vessels was improved by TOF-Spiral-short compared to CTA (P < .0001). In TOF-Spiral-short, diagnostic confidence was not reduced compared to TOF-CS in patients with vessel pathologies. We observed no significant difference in quantitative pathology assessment between TOF-Spiral-short and the other two modalities. TOF-Spiral-short enabled the correct identification of all vessel pathologies. CONCLUSIONS Accelerating TOF-MRA of brain-feeding arteries by a novel ultrashort spiral imaging sequence shows adequate image quality and sufficient diagnostic performance. Thus, TOF-Spiral-short holds potential for fast and reliable diagnostics of vessel pathologies, particularly in the acute setting.
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Affiliation(s)
- Tobias Greve
- Department of Diagnostic and Interventional Neuroradiology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.,Department of Neurosurgery, University Hospital, Ludwig-Maximilians-University, Campus Grosshadern, Munich, Germany
| | - Nico Sollmann
- Department of Diagnostic and Interventional Neuroradiology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.,TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Andreas Hock
- Health Systems Philips Switzerland, Horgen, Switzerland
| | - Claus Zimmer
- Department of Diagnostic and Interventional Neuroradiology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.,TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
| | - Jan S Kirschke
- Department of Diagnostic and Interventional Neuroradiology, Klinikum rechts der Isar, Technische Universität München, Munich, Germany.,TUM-Neuroimaging Center, Klinikum rechts der Isar, Technische Universität München, Munich, Germany
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Howard BM, Hu R, Barrow JW, Barrow DL. Comprehensive review of imaging of intracranial aneurysms and angiographically negative subarachnoid hemorrhage. Neurosurg Focus 2020; 47:E20. [PMID: 31786554 DOI: 10.3171/2019.9.focus19653] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2019] [Accepted: 09/20/2019] [Indexed: 11/06/2022]
Abstract
Intracranial aneurysms confer the risk of subarachnoid hemorrhage (SAH), a potentially devastating condition, though most aneurysms will remain asymptomatic for the lifetime of the patient. Imaging is critical to all stages of patient care for those who harbor an unruptured intracranial aneurysm (UIA), including to establish the diagnosis, to determine therapeutic options, to undertake surveillance in patients who elect not to undergo treatment or whose aneurysm(s) portends such a low risk that treatment is not indicated, and to perform follow-up after treatment. Neuroimaging is equally as important in patients who suffer an SAH. DSA remains the reference standard for imaging of intracranial aneurysms due to its high spatial and temporal resolution. As noninvasive imaging technology, such as CTA and MRA, improves, the diagnostic accuracy of such tests continues to increasingly approximate that of DSA. In cases of angiographically negative SAH, imaging protocols are necessary not only for diagnosis but also to search for an initially occult vascular lesion, such as a thrombosed, ruptured aneurysm that might be detected in a delayed fashion. Given the crucial role of neuroimaging in all aspects of care for patients with UIAs and SAH, it is incumbent on those who care for these patients, including cerebrovascular neurosurgeons, interventional neurologists and neuroradiologists, and diagnostic radiologists and neurointensivists, to understand the role of imaging in this disease and how individual members of the multispecialty team use imaging to ensure best practices to deliver cutting-edge care to these often complex cases. This review expounds on the role of imaging in the management of UIAs and ruptured intracranial aneurysms and in the workup of angiographically negative subarachnoid hemorrhage.
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Affiliation(s)
- Brian M Howard
- 1Department of Neurosurgery, and.,2Department of Radiology and Imaging Sciences, Division of Interventional Neuroradiology, Emory University School of Medicine, Atlanta; and
| | - Ranliang Hu
- 2Department of Radiology and Imaging Sciences, Division of Interventional Neuroradiology, Emory University School of Medicine, Atlanta; and
| | - Jack W Barrow
- 3Mercer University School of Medicine, Savannah, Georgia
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10
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Suzuki T, Genkai N, Nomura T, Abe H. Assessing the Hemodynamics in Residual Cavities of Intracranial Aneurysm after Coil Embolization with Combined Computational Flow Dynamics and Silent Magnetic Resonance Angiography. J Stroke Cerebrovasc Dis 2020; 29:105290. [PMID: 32992205 DOI: 10.1016/j.jstrokecerebrovasdis.2020.105290] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2020] [Revised: 08/21/2020] [Accepted: 08/26/2020] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND AND PURPOSE Metal artifacts limit computational fluid dynamics analysis after coil embolization. Silent magnetic resonance angiography reduces metal artifacts and improves visualization of the residual cavity of coil-embolized aneurysms. This study investigated the flow dynamics of the residual cavity after coil embolization using silent magnetic resonance angiography and computational fluid dynamics to elucidate the hemodynamic characteristics of recanalization. METHODS Twenty internal carotid-posterior communicating aneurysm cases treated with coil embolization and without stent assistance were followed up (mean±standard deviation, 13.0±6.1 months) and assessed using silent magnetic resonance angiography. The hemodynamic characteristics of the residual cavities in both types of aneurysms were compared between neck remnants, which persisted for >12 months (NR group), and those treated with coil compaction-induced body filling (BF group). Computational fluid dynamics analysis of each aneurysm was performed using morphological data obtained from silent magnetic resonance angiography. Pressure, pressure difference, normalized wall shear stress, and flow velocity were measured. RESULTS The residual cavity was well-visualized using silent magnetic resonance angiography and compared with those imaged using conventional time-of-flight magnetic resonance angiography, and eight internal carotid-posterior communicating aneurysms with neck remnants and body filling were investigated. The maximum pressure area was localized to the aneurysm wall in the NR group (n=4) and to sides of the coil surface in the BF group (n=4). No significant differences were observed for each hemodynamic parameter. CONCLUSIONS Combination of silent magnetic resonance angiography and computational fluid dynamics helps to understand the hemodynamic characteristics of residual cavity in coil- embolized aneurysms. The flow-impingement zone at the coil surface (maximum pressure area) may influence the risk for future coil compaction.
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Affiliation(s)
- Tomoaki Suzuki
- Department of Neurosurgery, Tachikawa General Hospital, 1-24 Asahioka, Nagaoka 940-8621, Japan; Department of Neurosurgery, Brain Research Institute, Niigata University, 1-757 Asahimachi-Dori, Niigata 951-8585, Japan.
| | - Nobuyuki Genkai
- Department of Neurosurgery, Tachikawa General Hospital, 1-24 Asahioka, Nagaoka 940-8621, Japan
| | - Toshiharu Nomura
- Department of Neurosurgery, Tachikawa General Hospital, 1-24 Asahioka, Nagaoka 940-8621, Japan
| | - Hiroshi Abe
- Department of Neurosurgery, Tachikawa General Hospital, 1-24 Asahioka, Nagaoka 940-8621, Japan
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11
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Mırçık E, Hakyemez B. New technique: the use of the THRIVE sequence in the follow-up of patients who received endovascular intracranial aneurysm treatment. Neuroradiology 2020; 63:399-407. [PMID: 32914366 DOI: 10.1007/s00234-020-02527-4] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2020] [Accepted: 08/16/2020] [Indexed: 11/26/2022]
Abstract
PURPOSE To determine the diagnostic accuracy of 3D time of flight MR angiography (TOF-MRA), contrast enhanced MR angiography (CE-MRA), and T1-weighted high-resolution isotropic volume examination (THRIVE) at 3 T for the evaluation of intracranial aneurysm occlusion after endovascular treatment and to evaluate the usability of the THRIVE sequence in endovascular treatment follow-up. METHODS In 3 T MR follow-up examinations of 66 aneurysms in 50 patients treated endovascularly, 3D TOF-MRA (index test), THRIVE (index test), and CE-MRA (reference standard) examinations were performed in a retrospective consecutive case series. Source images were classified as class 1, class 2, and class 3 according to the Raymond criteria using MIP (maximum intensity projection) techniques. The compatibility between sequences was evaluated with the Kappa test. The sensitivity and specificity were also calculated. RESULTS In the evaluation of THRIVE and CE-MRA sequences, compatibility was determined in 61 cases in total, with an overall fit of 61/66 (92.42%). A statistically significant correlation was found between THRIVE and CE-MRA (p < 0.001, κ = 0.800). In the evaluation of TOF and CE-MRA sequences, compatibility was determined in 54 cases in total, and the overall fit was 54/66 (81.8%). A statistically significant agreement was found between TOF and CE-MRA (p < 0.001, κ = 0.502). Assuming that CE-MRA is a reference standard, the sensitivity and specificity of the TOF sequence were 44.4% and 97.9%, respectively, and the sensitivity and specificity of the THRIVE sequence were 77.8% and 97.9%, respectively. CONCLUSION The THRIVE sequence can be used as a noncontrast method for monitoring endovascularly treated intracranial aneurysms.
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Affiliation(s)
- Emre Mırçık
- Department of Radiology, Patnos State Hospital, 04500, Patnos, Ağrı, Turkey
| | - Bahattin Hakyemez
- Department of Radiology, Bursa Uludag University Faculty of Medicine, 16059, Nilüfer, Bursa, Turkey.
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Chen G, Wei X, Lei H, Liqin Y, Yuxin L, Yakang D, Daoying G. Automated computer-assisted detection system for cerebral aneurysms in time-of-flight magnetic resonance angiography using fully convolutional network. Biomed Eng Online 2020; 19:38. [PMID: 32471439 PMCID: PMC7257213 DOI: 10.1186/s12938-020-00770-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/15/2019] [Accepted: 04/17/2020] [Indexed: 01/10/2023] Open
Abstract
Background As the rupture of cerebral aneurysm may lead to fatal results, early detection of unruptured aneurysms may save lives. At present, the contrast-unenhanced time-of-flight magnetic resonance angiography is one of the most commonly used methods for screening aneurysms. The computer-assisted detection system for cerebral aneurysms can help clinicians improve the accuracy of aneurysm diagnosis. As fully convolutional network could classify the image pixel-wise, its three-dimensional implementation is highly suitable for the classification of the vascular structure. However, because the volume of blood vessels in the image is relatively small, 3D convolutional neural network does not work well for blood vessels. Results The presented study developed a computer-assisted detection system for cerebral aneurysms in the contrast-unenhanced time-of-flight magnetic resonance angiography image. The system first extracts the volume of interest with a fully automatic vessel segmentation algorithm, then uses 3D-UNet-based fully convolutional network to detect the aneurysm areas. A total of 131 magnetic resonance angiography image data are used in this study, among which 76 are training sets, 20 are internal test sets and 35 are external test sets. The presented system obtained 94.4% sensitivity in the fivefold cross-validation of the internal test sets and obtained 82.9% sensitivity with 0.86 false positive/case in the detection of the external test sets. Conclusions The proposed computer-assisted detection system can automatically detect the suspected aneurysm areas in contrast-unenhanced time-of-flight magnetic resonance angiography images. It can be used for aneurysm screening in the daily physical examination.
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Affiliation(s)
- Geng Chen
- Academy for Engineering and Technology, Fudan University, 20 Handan Road, Shanghai, 200433, China.,Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 88 Keling Road, Suzhou, 215163, China
| | - Xia Wei
- Academy for Engineering and Technology, Fudan University, 20 Handan Road, Shanghai, 200433, China.,Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 88 Keling Road, Suzhou, 215163, China
| | - Huang Lei
- Department of Radiology, Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200040, China
| | - Yang Liqin
- Department of Radiology, Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200040, China
| | - Li Yuxin
- Department of Radiology, Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200040, China
| | - Dai Yakang
- Suzhou Institute of Biomedical Engineering and Technology, Chinese Academy of Sciences, 88 Keling Road, Suzhou, 215163, China.
| | - Geng Daoying
- Department of Radiology, Huashan Hospital, Fudan University, 12 Wulumuqi Middle Road, Shanghai, 200040, China.
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Greve T, Sollmann N, Hock A, Hey S, Gnanaprakasam V, Nijenhuis M, Zimmer C, Kirschke JS. Highly accelerated time-of-flight magnetic resonance angiography using spiral imaging improves conspicuity of intracranial arterial branches while reducing scan time. Eur Radiol 2019; 30:855-865. [DOI: 10.1007/s00330-019-06442-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2019] [Revised: 08/09/2019] [Accepted: 09/09/2019] [Indexed: 12/14/2022]
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Murakami T, Nishida T, Asai K, Kadono Y, Nakamura H, Fujinaka T, Kishima H. Long-Term Results and Follow-Up Examinations after Endovascular Embolization for Unruptured Cerebral Aneurysms. AJNR Am J Neuroradiol 2019; 40:1191-1196. [PMID: 31248865 DOI: 10.3174/ajnr.a6101] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/19/2019] [Accepted: 05/13/2019] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE The appropriate period of follow-up examinations after endovascular embolization for cerebral aneurysms using time-of-flight MR angiography is not well-known. We retrospectively investigated long-term results after endovascular embolization for unruptured cerebral aneurysms and evaluated the periods from embolization to recanalization and retreatment. MATERIALS AND METHODS Between April 2006 and March 2011, one hundred forty-eight unruptured aneurysms were treated with endovascular coil embolization. Among them, we investigated 116 unruptured aneurysms, which were followed up for >5 years. Time-of-flight MR angiography was performed at 1 day, 3-6 months, 1 year after the procedure, and every year thereafter. RESULTS The mean follow-up period was 7.0 ± 1.4 years. Recanalization was observed in 19 (16.3%) aneurysms within 2 years. Among them, retreatment for recanalization was performed in 8 (6.8%) aneurysms. No recanalization was detected in any aneurysms that had been stable in the first 2 years after embolization. A larger maximum aneurysm size was significantly correlated with recanalization (P = .019). CONCLUSIONS Aneurysms in which recanalization was not observed within 2 years after endovascular coil embolization were stable during a mean follow-up of 7 years. This result may be helpful in considering the appropriate span or frequency of follow-up imaging for embolized cerebral aneurysms.
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Affiliation(s)
- T Murakami
- From the Department of Neurosurgery (T.M., T.N., K.A., Y.K., H.N., H.K.), Osaka University Graduate School of Medicine, Osaka, Japan.,Department of Neurosurgery (T.M.), Osaka Neurological Institute, Osaka, Japan
| | - T Nishida
- From the Department of Neurosurgery (T.M., T.N., K.A., Y.K., H.N., H.K.), Osaka University Graduate School of Medicine, Osaka, Japan
| | - K Asai
- From the Department of Neurosurgery (T.M., T.N., K.A., Y.K., H.N., H.K.), Osaka University Graduate School of Medicine, Osaka, Japan
| | - Y Kadono
- From the Department of Neurosurgery (T.M., T.N., K.A., Y.K., H.N., H.K.), Osaka University Graduate School of Medicine, Osaka, Japan
| | - H Nakamura
- From the Department of Neurosurgery (T.M., T.N., K.A., Y.K., H.N., H.K.), Osaka University Graduate School of Medicine, Osaka, Japan
| | - T Fujinaka
- Department of Neurosurgery (T.F.), Osaka National Hospital, Osaka, Japan
| | - H Kishima
- From the Department of Neurosurgery (T.M., T.N., K.A., Y.K., H.N., H.K.), Osaka University Graduate School of Medicine, Osaka, Japan
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Teramoto S, Oishi H, Arai H. Comparative Analysis of Long-Term Effect of Stent-Assisted Coiling in Unruptured Sidewall-Type and Terminal-Type Aneurysms. World Neurosurg 2019; 126:e753-e757. [DOI: 10.1016/j.wneu.2019.02.145] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2018] [Revised: 02/14/2019] [Accepted: 02/15/2019] [Indexed: 11/30/2022]
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Ahmed SU, Mocco J, Zhang X, Kelly M, Doshi A, Nael K, De Leacy R. MRA versus DSA for the follow-up imaging of intracranial aneurysms treated using endovascular techniques: a meta-analysis. J Neurointerv Surg 2019; 11:1009-1014. [PMID: 31048457 DOI: 10.1136/neurintsurg-2019-014936] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 04/10/2019] [Accepted: 04/15/2019] [Indexed: 12/16/2022]
Abstract
BACKGROUND Treated aneurysms must be followed over time to ensure durable occlusion, as more than 20% of endovascularly treated aneurysms recur. While digital subtraction angiography (DSA) remains the gold standard, magnetic resonance angiography (MRA) is attractive as a non-invasive follow-up technique. Two different MRA techniques have traditionally been used: time-of-flight (TOF) and contrast-enhanced (CE) MRA. We analysed data from studies comparing MRA techniques with DSA for the follow-up of aneurysms undergoing endovascular treatment. Subgroup analysis of stent-assisted coiling (SAC) and flow diversion (FD) techniques was completed. METHODS Comprehensive searches using the Embase, PubMed, and Cochrane databases were performed and updated to November 2018. Pooled sensitivity and specificity were calculated using aneurysm occlusion status as defined by the Raymond-Roy occlusion grading scale. RESULTS The literature search yielded 1579 unique titles. Forty-three studies were included. For TOF-MRA, sensitivity and specificity of all aneurysms undergoing endovascular therapy were 88% and 94%, respectively. For CE-MRA, the sensitivity and specificity were 88% and 96%, respectively. For SAC and FD techniques, sensitivity and specificity of TOF-MRA were 86% and 95%, respectively. CE-MRA had sensitivity and specificity of 90% and 92%. CONCLUSION MRA is a reliable modality for the follow-up of aneurysms treated using endovascular techniques. While the data are limited, MRA techniques can also be used to reliably follow patients undergoing FD and SAC. However, clinical factors must be used to optimize follow-up regimens for individual patients.
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Affiliation(s)
| | - J Mocco
- The Mount Sinai Health System, New York, New York, USA
| | - Xiangnan Zhang
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Michael Kelly
- Royal University Hospital, University of Saskatchewan, Neurosurgery, Saskatoon, Saskatchewan, Canada
| | - Amish Doshi
- Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Kambiz Nael
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
| | - Reade De Leacy
- Department of Neurosurgery, Icahn School of Medicine at Mount Sinai, New York, New York, USA
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Satoh T, Hishikawa T, Hiramatsu M, Sugiu K, Date I. Visualization of Aneurysmal Neck and Dome after Coiling with 3D Multifusion Imaging of Silent MRA and FSE-MR Cisternography. AJNR Am J Neuroradiol 2019; 40:802-807. [PMID: 30948372 DOI: 10.3174/ajnr.a6026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2018] [Accepted: 03/11/2019] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Our aim was to visualize the precise configuration of the aneurysmal neck and dome with/without remnants combined with a coiled dome after coiling treatment for cerebral aneurysms. We developed 3D multifusion imaging of silent MRA and FSE-MR cisternography. MATERIALS AND METHODS We examined 12 patients with 3D multifusion imaging by composing 3D images reconstructed from TOF-MRA, silent MRA, and FSE-MR cisternography. The influence of magnetic susceptibility artifacts caused by metal materials affecting the configuration of the aneurysmal complex with coiling was assessed in a single 3D image. RESULTS In all cases, TOF-MRA failed to depict the aneurysmal neck complex precisely due to metal artifacts, whereas silent MRA delineated the neck and parent arteries at the coiled regions without serious metal artifacts. FSE-MR cisternography depicted the shape of the coiled aneurysmal dome and parent artery complex together with the brain parenchyma. With the 3D multifusion images of silent MRA and FSE-MR cisternography, the morphologic status of the coiled neck and parent arteries was clearly visualized with the shape of the dome in a single 3D image. CONCLUSIONS Silent MRA is a non-contrast-enhanced form of MRA. It depicts the coiled neck complex without serious metal artifacts. FSE-MR cisternography can delineate the shape of the coiled dome. In this small feasibility study, 3D multifusion imaging of silent MRA and FSE-MR cisternography allowed good visualization of key features of coiled aneurysms. This technique may be useful in the follow-up of coiled aneurysms.
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Affiliation(s)
- T Satoh
- From the Department of Neurological Surgery (T.S.), Ryofukai Satoh Neurosurgical Hospital, Fukuyama, Hiroshima, Japan
| | - T Hishikawa
- Department of Neurological Surgery (T.H., M.H., K.S., I.D.), Okayama University Graduate School of Medicine, Okayama, Okayama, Japan
| | - M Hiramatsu
- Department of Neurological Surgery (T.H., M.H., K.S., I.D.), Okayama University Graduate School of Medicine, Okayama, Okayama, Japan
| | - K Sugiu
- Department of Neurological Surgery (T.H., M.H., K.S., I.D.), Okayama University Graduate School of Medicine, Okayama, Okayama, Japan
| | - I Date
- Department of Neurological Surgery (T.H., M.H., K.S., I.D.), Okayama University Graduate School of Medicine, Okayama, Okayama, Japan
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Qassim AM, Guan S, Ngowo HS, Liu B, Xu H. Effectiveness of MRA on embolized intracranial aneurysms: a comparison of DSA, CE-MRA, and TOF-MRA. J Interv Med 2019; 1:32-41. [PMID: 34805829 PMCID: PMC8586576 DOI: 10.19779/j.cnki.2096-3602.2018.01.08] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Abstract
Purpose: The endovascular treatment of intracranial aneurysms was proven safe and effective compared to the alternative method of surgical clipping, despite the high recurrence rate. Follow-up of embolized intracranial aneurysms is mandatory for the early detection of recurrence and improved outcomes. DSA is used as the reference standard for this assessment. To determine the effectiveness of MRA in follow-up evaluations of intracranial aneurysms after embolization by comparing DSA, CE-MRA, and TOF-MRA. Materials and Methods: Sixty-eight consecutive patients undergoing DSA, TOF-MRA, and CE-MRA during an interval of <1 week were enrolled in this 6-month study. Images were evaluated for occlusion status, patency of the parent vessels, and artifacts. The modified Raymond-Roy occlusion classification and Aneurysm Embolization Grades were used to assess the occlusion status and initial DSA images for detection of recurrence in two filtered study phases with optimized selection criteria. Seventeen observers (phase I: 9, phase II: 8) independently interpreted the double-blinded images. Agreement was expressed with a Fleiss kappa value; p < 0.05 was considered significant. Results: This study included 68 patients with 77 aneurysms; 38 (49.35%) were treated with coil alone and 39 (50.65%) with stent-assisted coiling. In both phases, DSA was superior to TOF-MRA and CE-MRA using MRRC (Phase I: k = 0.567, p ≤ 0.001; k = 0.287, p ≤ 0.001; k = 0.117, p ≤ 0.001, respectively; Phase II: k = 0.503, p ≤ 0.001; k = 0.303, p ≤ 0.001; k = 0.115, p = 0.038, respectively). TOF-MRA was as effective as DSA (TOF: k = 0.335, p ≤ 0.001; DSA: k = 0.323, p ≤ 0.001) for recurrence detection. Conclusion: We suggest TOF-MRA as a first-line follow-up tool to detect aneurysm recurrence, and DSA to quantify the filling space to make a definite decision on re-embolization.
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Affiliation(s)
- Ally Mohamed Qassim
- East Campus of Zhengzhou University, Zhengzhou, China.,Department of Intervention Neuroradiology, The First Affiliated Hospital of Zhengzhou university, Zhengzhou, China
| | - Sheng Guan
- Department of Intervention Neuroradiology, The First Affiliated Hospital of Zhengzhou university, Zhengzhou, China
| | - Halfan Saidi Ngowo
- Department of Environmental Health and Ecological Science, Ifakara Health Institute, Ifakara, Morogoro, Tanzania
| | - Binghui Liu
- Department of Intervention Neuroradiology, The First Affiliated Hospital of Zhengzhou university, Zhengzhou, China
| | - Haowen Xu
- Department of Intervention Neuroradiology, The First Affiliated Hospital of Zhengzhou university, Zhengzhou, China
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Heo YJ, Jeong HW, Baek JW, Kim ST, Jeong YG, Lee JY, Jin SC. Pointwise Encoding Time Reduction with Radial Acquisition with Subtraction-Based MRA during the Follow-Up of Stent-Assisted Coil Embolization of Anterior Circulation Aneurysms. AJNR Am J Neuroradiol 2019; 40:815-819. [PMID: 30975655 DOI: 10.3174/ajnr.a6035] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2018] [Accepted: 03/11/2019] [Indexed: 11/07/2022]
Abstract
BACKGROUND AND PURPOSE Time-of-flight MR angiography, though widely used after coil embolization, is associated with limitations owing to magnetic susceptibility and radiofrequency shielding following stent-assisted coil embolization. We evaluated the pointwise encoding time reduction with radial acquisition (PETRA) sequence in subtraction-based MRA (qMRA) using an ultrashort TE relative to TOF-MRA during the follow-up of stent-assisted coil embolization for anterior circulation aneurysms. MATERIALS AND METHODS Twenty-five patients (3 men and 22 women; mean age, 59.1 ± 14.0 years) underwent stent-assisted coil embolization for anterior circulation aneurysms and were retrospectively evaluated using TOF-MRA and PETRA qMRA data from the same follow-up session. Two neuroradiologists independently reviewed both MRA findings and subjectively graded flow within the stents (relative to the latest DSA findings) and occlusion status (complete occlusion or neck/aneurysm remnant). Interobserver and intermodality agreement for TOF-MRA and PETRA qMRA were evaluated. RESULTS The mean score for flow visualization within the stents was significantly higher in PETRA qMRA than in TOF-MRA (P < .001 for both observers), and good interobserver agreement was reported (κ = 0.63). The aneurysm occlusion status of PETRA qMRA (observer 1, 92.0%; observer 2, 88.0%) was more consistent with DSA than with TOF-MRA (observer 1, 76.0%; observer 2, 80.0%), and there was a better intermodality agreement between DSA and PETRA qMRA than between DSA and TOF-MRA. CONCLUSIONS These findings indicate that PETRA qMRA is a useful follow-up technique for patients who have undergone stent-assisted coil embolization for anterior circulation aneurysms.
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Affiliation(s)
- Y J Heo
- From the Departments of Radiology (Y.J.H., H.W.J., J.W.B.)
| | - H W Jeong
- From the Departments of Radiology (Y.J.H., H.W.J., J.W.B.)
| | - J W Baek
- From the Departments of Radiology (Y.J.H., H.W.J., J.W.B.)
| | - S T Kim
- Neurosurgery (S.T.K., Y.G.J.)
| | | | - J Y Lee
- Internal Medicine (J.Y.L.), Inje University Busan Paik Hospital, Busan, Korea
| | - S-C Jin
- Department of Neurosurgery (S.-C.J.), Inje University Haeundae Paik Hospital, Busan, Korea
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Lu SS, Qi M, Zhang X, Mu XH, Schmidt M, Sun Y, Forman C, Speier P, Hong XN. Clinical Evaluation of Highly Accelerated Compressed Sensing Time-of-Flight MR Angiography for Intracranial Arterial Stenosis. AJNR Am J Neuroradiol 2018; 39:1833-1838. [PMID: 30213812 DOI: 10.3174/ajnr.a5786] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2018] [Accepted: 07/15/2018] [Indexed: 12/27/2022]
Abstract
BACKGROUND AND PURPOSE Time-of-flight MR angiography is the preferred imaging technique to assess intracranial arterial stenosis but is limited by a relatively long acquisition time. Compressed sensing provides an innovative approach in undersampling k-space to minimize the data-acquisition time. We aimed to evaluate the diagnostic accuracy of compressed sensing TOF for detecting intracranial arterial stenosis by comparison with conventional parallel imaging TOF-MRA. MATERIALS AND METHODS Compressed sensing TOF and parallel imaging TOF were performed in 22 patients with intracranial arterial stenosis. The MRA scan times were 2 minutes and 31 seconds and 4 minutes and 48 seconds for compressed sensing TOF and parallel imaging TOF, respectively. The reconstructed resolutions were 0.4 × 0.4 × 0.4 and 0.4 × 0.4 × 0.6 mm3 for compressed sensing TOF and parallel imaging TOF, respectively. The diagnostic quality of the images and visibility of the stenoses were independently ranked by 2 neuroradiologists blinded to the type of method and were compared using the Wilcoxon signed rank test. Concordance was calculated with the Cohen κ. Edge sharpness of the arteries and the luminal stenosis ratio were analyzed and compared using a paired-sample t test. RESULTS The interrater agreement was good to excellent. Compressed sensing TOF resulted in image quality comparable with that of parallel imaging TOF but boosted confidence in diagnosing arterial stenoses (P = .025). The edge sharpness of the intracranial arteries for compressed sensing TOF was significantly higher than that for parallel imaging TOF (P < .001). The luminal stenosis ratio on compressed sensing TOF showed no significant difference compared with that on parallel imaging TOF. CONCLUSIONS Compressed sensing TOF both remarkably reduced the scan time and provided adequate image quality for the diagnosis of intracranial arterial stenosis.
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Affiliation(s)
- S S Lu
- From the Department of Radiology (S.s.L., M.Q., X.Z., X.h.M., X.n.H.), The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - M Qi
- From the Department of Radiology (S.s.L., M.Q., X.Z., X.h.M., X.n.H.), The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - X Zhang
- From the Department of Radiology (S.s.L., M.Q., X.Z., X.h.M., X.n.H.), The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - X H Mu
- From the Department of Radiology (S.s.L., M.Q., X.Z., X.h.M., X.n.H.), The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
| | - M Schmidt
- Siemens Healthcare GmbH (M.S., C.F., P.S.), Erlangen, Germany
| | - Y Sun
- MR Collaboration NE Asia (Y.S.), Siemens Healthcare, Shanghai, China
| | - C Forman
- Siemens Healthcare GmbH (M.S., C.F., P.S.), Erlangen, Germany
| | - P Speier
- Siemens Healthcare GmbH (M.S., C.F., P.S.), Erlangen, Germany
| | - X N Hong
- From the Department of Radiology (S.s.L., M.Q., X.Z., X.h.M., X.n.H.), The First Affiliated Hospital of Nanjing Medical University, Nanjing, Jiangsu Province, China
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21
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Ikemura A, Yuki I, Suzuki H, Suzuki T, Ishibashi T, Abe Y, Urashima M, Dahmani C, Murayama Y. Time-resolved magnetic resonance angiography (TR-MRA) for the evaluation of post coiling aneurysms; A quantitative analysis of the residual aneurysm using full-width at half-maximum (FWHM) value. PLoS One 2018; 13:e0203615. [PMID: 30192859 PMCID: PMC6128576 DOI: 10.1371/journal.pone.0203615] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2018] [Accepted: 08/23/2018] [Indexed: 11/19/2022] Open
Abstract
Magnetic resonance image (MRI) is now widely used for imaging follow-up for post coiling brain aneurysms. However, the accuracy on the estimation of residual aneurysm, which is crucial for the retreatment planning, remains to be controversial. The purpose of this study is to evaluate a new post-processing technique that provides improved estimation of the residual aneurysm after coil embolization. One hundred aneurysms on 93 patients who underwent coil embolization for brain aneurysm were evaluated using the 1.5 Tesla time-resolved magnetic resonance angiography (TR-MRA) one year after the treatment. To minimize the inter-observer variability caused by the window level adjustment, an automatic post processing protocol using the full-width at half-maximum (FWHM) value was utilized. The result was then compared with that from the conventional cerebral angiography. Of the 97 aneurysms that underwent both TR-MRA and DSA, 23 (23.7%) showed residual neck / dome during follow-up. After window level adjustment, the size of the parent artery in the TR-MRA was consistent with that in the DSA. The reconstructed Volume Rendering images provided clear contours of the residual aneurysms and contributed to the understanding the configuration of residual aneurysm. The largest and the smallest diameter of the residual aneurysms was larger in the TR-MRA than in the DSA (8.05 vs. 7.72 mm, p = 0.0004; 4.99 vs. 4.19 mm, p = 0.007 respectively). The sensitivity, specificity, and positive and negative predictive values of TR-MRA compared to DSA were 100%, 97%, 73%, and 100%, respectively. Using the FWHM value to optimize the window level adjustment, the size of the residual component observed in the TR-MRA was larger compared to that in the DSA whereas the size of neck and the parent artery showed consistency between the two modalities. This image processing technique can be used as an effective screening tool for evaluating residual component in post-coiling brain aneurysms.
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Affiliation(s)
- Ayako Ikemura
- Department of Neurosurgery, The Jikei University Hospital, Tokyo, Japan
| | - Ichiro Yuki
- Department of Neurosurgery, The Jikei University Hospital, Tokyo, Japan
- * E-mail:
| | - Hiroaki Suzuki
- Department of Radiology, The Jikei University Hospital, Tokyo, Japan
| | - Tomoaki Suzuki
- Department of Neurosurgery, The Jikei University Hospital, Tokyo, Japan
| | | | - Yukiko Abe
- Department of Radiology, The Jikei University Hospital, Tokyo, Japan
| | - Mitsuyoshi Urashima
- Department of Molecular Epidemiology, The Jikei University School of Medicine, Tokyo, Japan
| | | | - Yuichi Murayama
- Department of Neurosurgery, The Jikei University Hospital, Tokyo, Japan
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22
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The utility of dual-energy CT for metal artifact reduction from intracranial clipping and coiling. RADIOLOGIA 2018. [DOI: 10.1016/j.rxeng.2018.02.007] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Mera Fernández D, Santos Armentia E, Bustos Fiore A, Villanueva Campos AM, Utrera Pérez E, Souto Bayarri M. The utility of dual-energy CT for metal artifact reduction from intracranial clipping and coiling. RADIOLOGIA 2018; 60:312-319. [PMID: 29699711 DOI: 10.1016/j.rx.2018.02.009] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2017] [Revised: 02/11/2018] [Accepted: 02/25/2018] [Indexed: 02/02/2023]
Abstract
OBJECTIVE To assess the ability of dual-energy CT (DECT) to reduce metal-related artifacts in patients with clips and coils in head CT angiography, and to analyze the differences in this reduction between both type of devices. MATERIALS AND METHODS Thirteen patients (6 clips, 7 coils) were selected and retrospectively analized. Virtual monoenergetic images (MEI) with photon energies from 40 to 150 keV were obtained. Noise was measured at the area of maximum artifact. Subjective evaluation of streak artifact was performed by two radiologists independently. Differences between noise values in all groups were tested by using the ANOVA test. Mann-Whitney U test was used to compare the differences between clips and coils. Coheńs κ statistic was used to determine interobserver agreement. RESULTS The lowest noise value was observed at high energy levels (p<0,05). Noise was higher in the coil group than in the clip group (p<0.001). Interobserver agreement was good (κ=0.72). CONCLUSIONS TCED with MEI helps to minimize the artifact from clips ands coils in patients who undergo head CT angiography. The reduction of the artifact is greater in patients with surgical clipping than in patients with endovascular coiling.
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Affiliation(s)
- D Mera Fernández
- Departamento de Radiología, Hospital Povisa, Vigo, Pontevedra, España.
| | - E Santos Armentia
- Departamento de Radiología, Hospital Povisa, Vigo, Pontevedra, España
| | - A Bustos Fiore
- Servicio de Diagnóstico por la Imagen, Hospital Universitari Dexeus, Barcelona, España
| | | | - E Utrera Pérez
- Departamento de Radiología, Hospital Povisa, Vigo, Pontevedra, España
| | - M Souto Bayarri
- Servicio de Radiodiagnóstico, XXI de Santiago de Compostela, A Coruña, España
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Nawka MT, Sedlacik J, Frölich A, Bester M, Fiehler J, Buhk JH. Multiparametric MRI of intracranial aneurysms treated with the Woven EndoBridge (WEB): a case of Faraday's cage? J Neurointerv Surg 2018; 10:988-994. [PMID: 29440326 DOI: 10.1136/neurintsurg-2017-013625] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2017] [Revised: 01/03/2018] [Accepted: 01/16/2018] [Indexed: 11/03/2022]
Abstract
OBJECTIVE To evaluate multiparametric MRI including non-contrast and contrast-enhanced morphological and angiographic techniques for intracranial aneurysms treated with the single-layer Woven EndoBridge (WEB) embolization system applying simultaneous digital subtraction angiography (DSA) as the reference of standard. MATERIALS AND METHODS We retrospectively identified all patients with incidental and acute ruptured intracranial aneurysms treated with a WEB device (WEB SL and WEB SLS) between March 2014 and June 2016 in our neurovascular center with early (within 7 days) postinterventional multiparametric MRI as well as mid-term (5-8 months) follow-up MRI and DSA available. Occlusion rates were recorded both in DSA and MR angiography (MRA). In MRI, signal intensities within the WEB as well as in the occluded dome distal to the WEB, if present, were measured by region-of-interest (ROI) analysis. RESULTS Twenty-five patients fulfilled the inclusion criteria. Rates of complete/adequate occlusion at mid-term follow-up were 84% with both MRA and DSA. A strong signal loss within the WEB was observed in all MR sequences at initial and follow-up examinations. ROI analysis did not reveal significant differences in non-contrast (P=0.946) and contrast-enhanced imaging (P=0.377). A T1-hyperintense thrombus in the non-WEB-carrying dome was a frequent observation. CONCLUSIONS Signal intensity measurements in multiparametric MRI suggest that neither contrast-enhanced MRA nor morphological sequences are capable of revealing reliable information on the WEB lumen, presumably due to radio frequency shielding. MRI is therefore not suitable for confirming complete thrombus formation within the WEB.
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Affiliation(s)
- Marie Teresa Nawka
- Department of Diagnostic and Interventional Neuroradiology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Jan Sedlacik
- Department of Diagnostic and Interventional Neuroradiology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Andreas Frölich
- Department of Diagnostic and Interventional Neuroradiology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Maxim Bester
- Department of Diagnostic and Interventional Neuroradiology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Jens Fiehler
- Department of Diagnostic and Interventional Neuroradiology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Jan-Hendrik Buhk
- Department of Diagnostic and Interventional Neuroradiology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
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Ernst M, Buchholz A, Bourcier R, Desal H, Le Floch PY, Möhlenbruch M, Bendszus M, Fiehler J. Voxel based analysis of recurrence dynamics in intracranial aneurysms after coiling. J Neurointerv Surg 2017; 10:571-576. [PMID: 29089416 DOI: 10.1136/neurintsurg-2017-013311] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2017] [Revised: 09/08/2017] [Accepted: 09/08/2017] [Indexed: 11/03/2022]
Abstract
BACKGROUND Understanding aneurysm growth is critical for the appropriate follow-up of patients after coil embolization and the need for retreatment. The purpose of the study was to stratify the growth dynamics of aneurysm recurrences after coiling by volumetric analysis and to determine predictive factors for aneurysm recurrences. METHODS Source images of follow-up three-dimensional time of flight MR angiography (ToF-MRA) scans were compared with the first post-interventional ToF-MRA scan and analyzed for residual flow after co-registration using ANALYZE-software. In the event of incomplete occlusion, the residual volume was segmented and calculated. Growth dynamic was determined for each aneurysm after embolization. RESULTS We analyzed 326 patients with 345 aneurysms from two centers. Each case had at least two ToF-MRA examinations after endovascular therapy. The mean observation interval was 59 months. Volumetric analysis of 1139 follow-up MRAs revealed that 218/345 aneurysms (63.2%) showed complete occlusion on initial follow-up imaging, and of these 95.0% remained stable. A steady increase in intra-aneurysmal flow was observed in 83/345 (24.1%). Less frequent observations were a steep increase (21/345; 6.1%) and a decrease (27/345; 7.8%). Independent predictors of increasing residual flow were greatest aneurysm diameter, total coil length, and incomplete occlusion. CONCLUSIONS Volumetric analysis of registered three-dimensional ToF-MRA follow-up datasets allows the detection of different growth patterns with high precision, avoids the low inter-rater reliability, and represents a promising approach for future studies that include analysis of more complex predictors of residual flow. In cases of aneurysm recurrence after coiling, the major pattern seems to be a steady increase in intra-aneurysmal flow over several months.
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Affiliation(s)
- Marielle Ernst
- Department of Diagnostic and Interventional Neuroradiology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Anika Buchholz
- Department of Medical Biometry and Epidemiology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
| | - Romain Bourcier
- Service de Neuroradiologie Diagnostique et Interventionnelle, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Hubert Desal
- Service de Neuroradiologie Diagnostique et Interventionnelle, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Pierre-Yves Le Floch
- Service de Neuroradiologie Diagnostique et Interventionnelle, Centre Hospitalier Universitaire de Nantes, Nantes, France
| | - Markus Möhlenbruch
- Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany
| | - Martin Bendszus
- Department of Neuroradiology, Heidelberg University Hospital, Heidelberg, Germany
| | - Jens Fiehler
- Department of Diagnostic and Interventional Neuroradiology, University Medical Centre Hamburg-Eppendorf, Hamburg, Germany
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Binyamin TR, Dahlin BC, Waldau B. Comparison of 3D TOF MR angiographic accuracy in predicting Raymond grade of flow-diverted versus coiled intracranial aneurysms. J Clin Neurosci 2017; 42:182-185. [PMID: 28457861 DOI: 10.1016/j.jocn.2017.03.009] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2016] [Accepted: 03/05/2017] [Indexed: 10/19/2022]
Abstract
The accuracy of 3D time of Flight Magnetic Resonance Angiography (TOF MRA) has been studied extensively for following coiled intracranial aneurysms. It is used by many clinicians for non-invasive follow-up because of its adequate sensitivity in predicting aneurysmal recanalization compared to diagnostic cerebral angiography. The data on the accuracy of 3D TOF MRA for the Pipeline™ Embolization Device (PED) are sparse. In a retrospective chart review, we compared the accuracy of 3D TOF MRA of PED to coil embolization at our institution. 3D TOF MRA had a lower sensitivity and positive predictive value in detecting aneurysmal filling in PED-treated versus coiled aneurysms (57% versus 87% and 80% versus 100%, respectively). Analysis of discrepancies between conventional diagnostic angiography and 3D TOF MRA revealed that 3D TOF MRA was inaccurate in the setting of small residual necks and slow residual filling of the dome with fluid-fluid layers. Therefore, contrasted studies such as contrast-enhanced MRA may be preferred for non-invasively following PED-treated aneurysms to increase accuracy.
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Affiliation(s)
- Tamar R Binyamin
- Department of Neurological Surgery, University of California, Davis, Sacramento, CA 95811, United States
| | - Brian C Dahlin
- Department of Radiology, University of California, Davis, Sacramento, CA 95811, United States
| | - Ben Waldau
- Department of Neurological Surgery, University of California, Davis, Sacramento, CA 95811, United States.
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Shang S, Ye J, Luo X, Qu J, Zhen Y, Wu J. Follow-up assessment of coiled intracranial aneurysms using zTE MRA as compared with TOF MRA: a preliminary image quality study. Eur Radiol 2017; 27:4271-4280. [PMID: 28382536 DOI: 10.1007/s00330-017-4794-z] [Citation(s) in RCA: 30] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2016] [Revised: 02/15/2017] [Accepted: 03/07/2017] [Indexed: 10/19/2022]
Abstract
OBJECTIVES To prospectively assess coiled intracranial aneurysms using a novel non-contrast enhanced zero echo time (zTE) MR angiography (MRA) method, and compare its image quality with time-of-flight (TOF) MRA, using digital subtraction angiography (DSA) as reference. METHODS Twenty-five patients (10 males and 15 females; age 53.96 ± 12.46 years) were enrolled in this monocentric study. MRA sequences were performed 24 h before DSA. Susceptibility artefact intensity and flow signal within the parent artery were carried out using a 4-point scale. Occlusion status was assessed using the 3-grade Montreal scale. RESULTS Scores of zTE were higher than TOF for both susceptibility artefact intensity (3.42 ± 0.64, 2.92 ± 0.63, P = 0.01) and flow signal (3.66 ± 0.95, 3.24 ± 1.24, P = 0.01). DSA revealed 17 complete occlusions, five residual neck aneurysms and two residual aneurysms. Inter-observer agreement was excellent (weighted κ: 0.89) for zTE and good (weighted κ: 0.68) for TOF. Intermodality agreement was excellent for zTE (weighted κ: 0.95) and good for TOF (weighted κ: 0.80). Correlations of both MRA sequences with DSA were high (zTE, Spearman's ρ: 0.91; TOF, Spearman's ρ: 0.81). CONCLUSIONS zTE MRA showed promising results for follow-up assessment of coiled intracranial aneurysms and was superior to TOF MRA for visualizing the parent artery and evaluating occlusion status. KEY POINTS • Various MRA sequences were applied for follow-up assessment of coiled intracranial aneurysms. • zTE MRA was less sensitive to susceptibility artefacts and haemodynamics. • In this monocentric study, zTE MRA was equivalent to DSA. • zTE MRA maybe an alternative to TOF MRA for follow-up assessment.
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Affiliation(s)
- Song'an Shang
- Department of Radiology, The Second Xiangya Hospital, Central South University, Changsha, Hunan, 410011, China
| | - Jing Ye
- Department of Radiology, Northern Jiangsu People's Hospital, Yangzhou, Jiangsu, 225001, China
| | - Xianfu Luo
- Department of Radiology, Northern Jiangsu People's Hospital, Yangzhou, Jiangsu, 225001, China
| | - Jianxun Qu
- MR Enhanced Application, GE Healthcare, Beijing, 100176, China
| | - Yong Zhen
- Department of Neurosurgery, Northern Jiangsu People's Hospital, Yangzhou, Jiangsu, 225001, China
| | - Jingtao Wu
- Department of Radiology, Northern Jiangsu People's Hospital, Yangzhou, Jiangsu, 225001, China.
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Kim HJ, Yoon DY, Kim ES, Lee HJ, Jeon HJ, Lee JY, Cho BM. Intraobserver and interobserver variability in CT angiography and MR angiography measurements of the size of cerebral aneurysms. Neuroradiology 2017; 59:491-497. [PMID: 28343249 DOI: 10.1007/s00234-017-1826-y] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/07/2017] [Accepted: 03/15/2017] [Indexed: 11/26/2022]
Abstract
PURPOSE Accurate and reliable measurement of aneurysm size is important for treatment planning. The purpose of this study was to determine intraobserver and interobserver variability of CTA and MRA for measurement of the size of cerebral aneurysms. METHODS Thirty patients with 33 unruptured cerebral aneurysms (saccular, >3 mm in their maximal dimension, with no daughter sacs or lobulations) who underwent 256-row multislice CTA, 3-D TOF MRA at 3.0T, and 3D rotational angiography (3DRA) were retrospectively analyzed. Three independent observers measured the neck, height, and width of the aneurysms using the CTA and MRA images. Intraobserver and interobserver variability of CTA and MRA measurements was evaluated using the standardized difference and intraclass correlation coefficient, with 3DRA measurements as the reference standard. In addition, the mean values of the measurements using CTA and MRA were compared with those using 3DRA. RESULTS The overall intraobserver and interobserver standardized differences in CTA/MRA were 12.83-15.92%/13.48-17.45% and 14.08-17.00%/12.08-17.67%, respectively. The overall intraobserver and interobserver intraclass correlation coefficients of CTA/MRA were 0.88-0.98/0.84-0.96 and 0.86-0.98/0.85-0.95, respectively. Compared to the height and width measurements, measurements of the neck dimensions showed higher intraobserver and interobserver variability. The sizes of the cerebral aneurysms measured by CTA and MRA were 1.13-9.26 and 5.20-9.67% larger than those measured by 3DRA, respectively; however, these differences were not statistically significant. CONCLUSION There were no noticeable differences between intraobserver and interobserver variability for both CTA- and MRA-based measurements of the size of cerebral aneurysms.
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Affiliation(s)
- Hye Jeong Kim
- Department of Radiology, Kangnam Sacred Heart Hospital, Hallym University College of Medicine, Seoul, South Korea
| | - Dae Young Yoon
- Department of Radiology, Kangdong Seong-Sim Hospital, Hallym University College of Medicine, 150, Seongan-ro Gangdong-Gu, Seoul, 134-701, South Korea.
| | - Eun Soo Kim
- Department of Radiology, Hallym University Sacred Heart Hospital, Hallym University College of Medicine, Anyang, Gyeonggi-do, South Korea
| | - Hyung Jin Lee
- Department of Radiology, Kangdong Seong-Sim Hospital, Hallym University College of Medicine, 150, Seongan-ro Gangdong-Gu, Seoul, 134-701, South Korea
| | - Hong Jun Jeon
- Department of Neurosurgery, Kangdong Seong-Sim Hospital, Hallym University College of Medicine, Seoul, South Korea
| | - Jong Young Lee
- Department of Neurosurgery, Kangdong Seong-Sim Hospital, Hallym University College of Medicine, Seoul, South Korea
| | - Byung-Moon Cho
- Department of Neurosurgery, Kangdong Seong-Sim Hospital, Hallym University College of Medicine, Seoul, South Korea
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Ueda F, Uchiyama N, Mohri M, Misaki K, Matsui O, Kida S, Sanada J, Yoshikawa J, Aburano H, Yoshie Y, Gabata T. Long-term predictive factors of the morphology based outcome in bare platinum coiled intracranial aneurysms: Evaluation by pre- and post-contrast 3D time-of-flight MR angiography. Neurol Neurochir Pol 2017; 51:116-126. [PMID: 28256206 DOI: 10.1016/j.pjnns.2017.01.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/17/2016] [Revised: 11/06/2016] [Accepted: 01/09/2017] [Indexed: 11/29/2022]
Abstract
PURPOSE Our aim was to identify long-term predictive factors of the morphology-based outcome (MBO) of bare platinum coiled intracranial aneurysms. MATERIALS AND METHODS A retrospective analysis of 96 bare platinum coiled intracranial aneurysms followed up from 1997 to 2016 using pre- and post-contrast 3D time-of-flight MR angiography (MRA) was performed. Logistic regression analysis was used to identify factors associated with a positive history of surrounding coil mass enhancement (SCME) and poor MBO. Spearman's rank correlation test was used to analyze the relationship between the initial angiographic result (IAR) class, sequential change of the SCME category, and MBO grade. RESULTS Factors independently associated with poor MBO were incomplete IAR (OR=14.94, 95%CI: 2.46, 289.21, P=0.002) and a history of SCME (OR=4.13, 95% CI: 1.05, 18.65, P=0.043). The MBO grade strongly correlated with the IAR class (correlation coefficient [r]=0.84, P<0.0001). MBO grade correlated with sequential change of the SCME category (r=0.56, P<0.0001). The sequential change of the SCME category correlated with IAR class (r=0.53, P<0.0001). CONCLUSION Although IAR and its class were strong long-term predictive factors of MBO, a history of SCME and upgrading of sequential change of SCME category were also long-term predictive factors of the MBO of bare platinum coiled intracranial aneurysms.
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Affiliation(s)
- Fumiaki Ueda
- Department of Radiology, Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Japan.
| | - Naoyuki Uchiyama
- Department of Neurosurgery, Division of Neuroscience, Graduate School of Medical Science, Kanazawa University, Japan
| | - Masanao Mohri
- Department of Neurosurgery, Division of Neuroscience, Graduate School of Medical Science, Kanazawa University, Japan
| | - Kouichi Misaki
- Department of Neurosurgery, Division of Neuroscience, Graduate School of Medical Science, Kanazawa University, Japan
| | - Osamu Matsui
- Department of Advanced Medical Imaging, Graduate School of Medical Science, Kanazawa University, Japan
| | - Shinya Kida
- Department of Neurosurgery, Fukui Prefectural Hospital, Japan
| | - Junichiro Sanada
- Department of Radiology, Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Japan
| | - Jun Yoshikawa
- Department of Radiology, Fukui Prefectural Hospital, Japan
| | - Hiroyuki Aburano
- Department of Radiology, Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Japan
| | - Yuichi Yoshie
- Department of Radiology, Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Japan
| | - Toshifumi Gabata
- Department of Radiology, Division of Cardiovascular Medicine, Graduate School of Medical Science, Kanazawa University, Japan
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Rouchaud A, Brinjikji W, Dai D, Ding YH, Gunderson T, Schroeder D, Spelle L, Kallmes DF, Kadirvel R. Autologous adipose-derived mesenchymal stem cells improve healing of coiled experimental saccular aneurysms: an angiographic and histopathological study. J Neurointerv Surg 2017; 10:60-65. [PMID: 28077523 DOI: 10.1136/neurintsurg-2016-012867] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2016] [Revised: 12/14/2016] [Accepted: 12/15/2016] [Indexed: 01/06/2023]
Abstract
PURPOSE Long-term occlusion of coiled aneurysms frequently fails, probably because of poor intrasaccular healing and inadequate endothelialization across the aneurysm neck. The purpose of this study was to determine if attachment of autologous mesenchymal stem cells (MSCs) to platinum coils would improve the healing response in an elastase-induced aneurysm model in rabbits. MATERIALS AND METHODS With approval from the institutional animal care and use committee, aneurysms were created in rabbits and embolized with control platinum coils (Axium; Medtronic) (n=6) or coils seeded ex vivo with autologous adipose-tissue MSCs (n=7). Aneurysmal occlusion after embolization was evaluated at 1 month with angiography. Histological samples were analyzed by gross imaging and graded on the basis of neck and dome healing on H&E staining. Fibrosis was evaluated using a ratio of the total area presenting collagen. Endothelialization of the neck was quantitatively analyzed using CD31 immunohistochemistry. χ2 and Student's t-test were used to compare groups. RESULTS Healing score (11.5 vs 8.0, p=0.019), fibrosis ratio (10.3 vs 0.13, p=0.006) and endothelialization (902 262 μm2 vs 31 810 μm2, p=0.041) were significantly greater in the MSC group. The MSC group showed marked cellular proliferation and thrombus organization, with a continuous membrane bridging the neck of the aneurysm. Angiographic stable or progressive occlusion rate was significantly lower in the MSC group (0.00, 95% CI 0.00 to 0.41) compared with controls (0.67, 95% CI 0.22 to 0.96) (p=0.02). CONCLUSIONS Autologous MSCs attached to platinum coils significantly improve histological healing, as they result in improved neck endothelialization and collagen matrix formation within the aneurysm sac.
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Affiliation(s)
- Aymeric Rouchaud
- Applied Neuroradiology Laboratory, Mayo Clinic, Rochester, Minnesota, USA.,Department of Interventional Neuroradiology, NEURI Center, Le Kremlin-Bicetre, France
| | | | - Daying Dai
- Applied Neuroradiology Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Yong-Hong Ding
- Applied Neuroradiology Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Tina Gunderson
- Health Sciences Research, Division of Biomedical Statistics and Informatics, Mayo Clinic, Rochester, USA
| | - Dana Schroeder
- Applied Neuroradiology Laboratory, Mayo Clinic, Rochester, Minnesota, USA
| | - Laurent Spelle
- Department of Interventional Neuroradiology, NEURI Center, Le Kremlin-Bicetre, France
| | - David F Kallmes
- Applied Neuroradiology Laboratory, Mayo Clinic, Rochester, Minnesota, USA
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Thamburaj K, Cockroft K, Agarwal AK, Sabat S, Kalapos P. A Comparison of Magnetic Resonance Angiography Techniques for the Evaluation of Intracranial Aneurysms Treated With Stent-assisted Coil Embolization. Cureus 2016; 8:e909. [PMID: 28083453 PMCID: PMC5208631 DOI: 10.7759/cureus.909] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
AIM To identify the effective magnetic resonance angiography (MRA) technique to monitor intracranial aneurysms treated with stent-assisted coiling. MATERIALS AND METHODS Retrospective analysis of various MRA techniques was performed in 42 patients. Three neuroradiologists independently compared non-contrast time of flight (ncTOF) MRA of the head, contrast-enhanced time of flight (cTOF) MRA of the head and dynamic contrast-enhanced MRA (CEMRA) of the head and neck or of the head. Digital subtraction angiography (DSA) was available for comparison in 32 cases. Inter-rater agreement (kappa statistic) was assessed. RESULTS Artifactual in-stent severe stenosis or flow gap was identified by ncTOF MRA in 23 of 42 cases (55%) and by cTOF MRA in 23 of 38 cases (60%). DSA excluded in-stent stenosis or occlusion in all 32 cases. No difference was noted between ncTOF and cTOF in the demonstration of neck remnants or residual aneurysms in three cases each. CEMRA of the head and neck or of the head was rated superior to ncTOF and cTOF MRA by all three investigators in seven out of eight cases. In one case, all three techniques demonstrated signifcant artifacts due to double stent placement during coiling. The kappa statistic revealed 0.8 agreement between investigators. CONCLUSIONS In the assessment of stent-assisted coiling of intracranial aneurysm, both ncTOF and cTOF MRA show similar results. CEMRA tends to show better flow signals in stent and residual aneurysm.
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Affiliation(s)
| | - Kevin Cockroft
- Department of Neurosurgery, Penn State Hershey Medical Center
| | - Amit K Agarwal
- Department of Radiology, Penn State Hershey Medical Center
| | - Shyam Sabat
- Department of Radiology, Penn State Hershey Medical Center
| | - Paul Kalapos
- Department of Radiology, Penn State Hershey Medical Center
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32
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Can we now dispense with DSA in the evaluation of aneurysm occlusion even in the most crucial first follow-up after endovascular treatment? Clin Neurol Neurosurg 2016; 149:136-42. [DOI: 10.1016/j.clineuro.2016.08.005] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2016] [Revised: 07/27/2016] [Accepted: 08/01/2016] [Indexed: 11/21/2022]
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Soize S, Gawlitza M, Raoult H, Pierot L. Imaging Follow-Up of Intracranial Aneurysms Treated by Endovascular Means. Stroke 2016; 47:1407-12. [DOI: 10.1161/strokeaha.115.011414] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2015] [Accepted: 02/23/2016] [Indexed: 12/21/2022]
Affiliation(s)
- Sebastien Soize
- From the Department of Neuroradiology, Hôpital Maison Blanche, Université Reims-Champagne-Ardenne, Reims, France (S.S., L.P.); Department of Neuroradiology, University Hospital Leipzig, Leipzig, Germany (M.G.); and Department of Neuroradiology, Hôpital Pontchaillou, University of Rennes, Rennes, France (H.R.)
| | - Matthias Gawlitza
- From the Department of Neuroradiology, Hôpital Maison Blanche, Université Reims-Champagne-Ardenne, Reims, France (S.S., L.P.); Department of Neuroradiology, University Hospital Leipzig, Leipzig, Germany (M.G.); and Department of Neuroradiology, Hôpital Pontchaillou, University of Rennes, Rennes, France (H.R.)
| | - Hélène Raoult
- From the Department of Neuroradiology, Hôpital Maison Blanche, Université Reims-Champagne-Ardenne, Reims, France (S.S., L.P.); Department of Neuroradiology, University Hospital Leipzig, Leipzig, Germany (M.G.); and Department of Neuroradiology, Hôpital Pontchaillou, University of Rennes, Rennes, France (H.R.)
| | - Laurent Pierot
- From the Department of Neuroradiology, Hôpital Maison Blanche, Université Reims-Champagne-Ardenne, Reims, France (S.S., L.P.); Department of Neuroradiology, University Hospital Leipzig, Leipzig, Germany (M.G.); and Department of Neuroradiology, Hôpital Pontchaillou, University of Rennes, Rennes, France (H.R.)
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Gao Y, Lu Z, Chen C, Cui X, Liu Y, Zheng T, Jiang X, Zeng C, Quan D, Wang Q. Mesenchymal stem cells and endothelial progenitor cells accelerate intra-aneurysmal tissue organization after treatment with SDF-1α-coated coils. Neurol Res 2016; 38:333-41. [PMID: 27125512 DOI: 10.1080/01616412.2016.1164433] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
Recurrences of aneurysms remain the major drawback of detachable coils for the endovascular treatment of intracranial aneurysms. The aim of the present study is to develop new modified coils, coating the surface of platinum coils with silk fibroin (SF) consisting of stromal cell-derived factor-1α (SDF-1α), and evaluate its acceleration of organization of cavities and reduction of lumen size in a rat aneurysm model. The morphological characteristics of SDF-1α-coated coils were examined using scanning electron microscopy (SEM). Fifty experimental aneurysms were created and randomly divided into five groups: three groups were embolized with SDF-1α-coated coils (8 mm) and two of these groups need transplantation of mesenchymal stem cells (MSCs) or endothelial progenitor cells (EPCs); one group was embolized with bare coils (8 mm) and another group severed as control. After coil implantation for 14 or 28 days, the coils were harvested and histological analysis was performed. SEM photographs showed that SF/SDF-1α-coated coils have uniform size and a thin film compared with bare coils. In the group treated with SDF-1α-coated coils, tissue organization was accelerated and the proliferation of α-smooth muscle actin positive cells was promoted in the aneurysmal sac. Compared with unmodified coils, on day 28, tissue organization was significantly greater in the group treated with SDF-1α-coated coils and MSC or EPC transplantation. These results suggest that SDF-1α-coated coils with MSC or EPC transplantation may be beneficial in the aneurysm healing and endothelialization at the orifice of embolized aneurysm.
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Affiliation(s)
- Yuyuan Gao
- a The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital , Southern Medical University , Guangzhou , China.,b Graduate School of Southern Medical University , Guangzhou , China.,c Department of Neurology , Guangdong General Hospital, Guangdong Academy of Medical Sciences, Guangdong Neuroscience Institute , Guangzhou , China
| | - Ziming Lu
- a The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital , Southern Medical University , Guangzhou , China.,b Graduate School of Southern Medical University , Guangzhou , China
| | - Chengwei Chen
- a The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital , Southern Medical University , Guangzhou , China.,b Graduate School of Southern Medical University , Guangzhou , China
| | - Xubo Cui
- a The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital , Southern Medical University , Guangzhou , China.,b Graduate School of Southern Medical University , Guangzhou , China
| | - Yaqi Liu
- a The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital , Southern Medical University , Guangzhou , China.,b Graduate School of Southern Medical University , Guangzhou , China
| | - Tao Zheng
- a The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital , Southern Medical University , Guangzhou , China.,b Graduate School of Southern Medical University , Guangzhou , China
| | - Xiaodan Jiang
- a The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital , Southern Medical University , Guangzhou , China
| | - Chi Zeng
- d School of Chemistry and Chemical Engineering , Sun Yat-Sen University , Guangzhou , China
| | - Daping Quan
- d School of Chemistry and Chemical Engineering , Sun Yat-Sen University , Guangzhou , China
| | - Qiujing Wang
- a The National Key Clinical Specialty, The Engineering Technology Research Center of Education Ministry of China, Guangdong Provincial Key Laboratory on Brain Function Repair and Regeneration, Department of Neurosurgery, Zhujiang Hospital , Southern Medical University , Guangzhou , China
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Jin Z, Arimura H, Kakeda S, Yamashita F, Sasaki M, Korogi Y. An ellipsoid convex enhancement filter for detection of asymptomatic intracranial aneurysm candidates in CAD frameworks. Med Phys 2016; 43:951-60. [DOI: 10.1118/1.4940349] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
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Zheng S, van der Bom IMJ, Zu Z, Lin G, Zhao Y, Gounis MJ. Chemical exchange saturation transfer effect in blood. Magn Reson Med 2015; 71:1082-92. [PMID: 23661508 DOI: 10.1002/mrm.24770] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
PURPOSE In this report, the feasibility of using blood as an agent for Chemical Exchange Saturation Transfer (CEST) effect is investigated. METHODS The CEST effect of porcine blood samples was investigated on a 3.0 T MRI scanner using various power levels and on a 14.1 T NMR spectrometer. As a proof-of-concept that CEST can be used to image blood in vivo, the technique was applied in two locations of healthy human volunteers, namely, the femoral artery and the M1-segment of the middle cerebral artery. RESULTS The blood sample experiments showed that maximum CEST Magnetization Transfer Ratio asymmetry (MTRasym) values of ∼ 12% were achieved, with likely contributions from multiple blood components. These findings were confirmed during the in vivo experiments where CEST signal of blood was clearly greater than surrounding muscular (2%) and brain tissue (3%). CONCLUSION Ex vivo and in vivo results show that blood is a suitable CEST agent that generates sufficient CEST contrast relative to surrounding tissue.
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Affiliation(s)
- Shaokuan Zheng
- Department of Radiology, UMASS Medical School, Worcester, Massachusetts, USA
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Mine B, Tancredi I, Aljishi A, Alghamdi F, Beltran M, Herchuelz M, Lubicz B. Follow-up of intracranial aneurysms treated by a WEB flow disrupter: a comparative study of DSA and contrast-enhanced MR angiography. J Neurointerv Surg 2015; 8:615-20. [DOI: 10.1136/neurintsurg-2015-011644] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2015] [Accepted: 05/04/2015] [Indexed: 11/03/2022]
Abstract
ObjectiveTo compare contrast-enhanced MR angiography (CE-MRA) and DSA for the follow-up of intracranial aneurysms (IAs) treated with the Woven EndoBridge embolization system DL (WEB DL; Sequent Medical, Aliso Viejo, California, USA).Materials and methodsWe retrospectively identified all patients treated with a WEB DL between November 2010 and February 2013 in 2 hospitals. The IA occlusion was graded on follow-up CE-MRA and DSA by 4 independent readers and by 2 readers reaching a consensus, respectively. Interobserver agreement for MRA and intertechnique agreement was evaluated by calculating linear weighted κ.ResultsFifteen patients with 16 IAs were included. Mean delay between MRA and DSA was 2 months (range 0–16 months). Interobserver agreement for MRA was substantial to almost perfect (κ=0.686–0.921; mean κ=0.809). Intertechnique agreement was moderate to substantial (κ=0.579–0.724; mean κ=0.669). Only three out of five inadequately occluded IAs were detected by MRA.ConclusionsCE-MRA is a useful tool for the follow-up of IAs treated with a WEB DL. However, early follow-up with DSA remains mandatory to detect inadequately occluded IAs.
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Ernst M, Yoo AJ, Kriston L, Schönfeld MH, Vettorazzi E, Fiehler J. Is visual evaluation of aneurysm coiling a reliable study end point? Systematic review and meta-analysis. Stroke 2015; 46:1574-81. [PMID: 25944331 DOI: 10.1161/strokeaha.114.008513] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2014] [Accepted: 04/10/2015] [Indexed: 11/16/2022]
Abstract
BACKGROUND AND PURPOSE Angiographic occlusion as a surrogate marker of satisfactory aneurysm treatment is commonly used in clinical trials although some pitfalls have to be considered. To investigate the inter-rater reliability of visual rating of aneurysm occlusion as study end point, we performed a systematic review and meta-analysis. METHODS Electronic databases (MEDLINE, EMBASE, PubMed, and the Cochrane Library) were searched up to June 2014. Assessment of risk for bias was based on the Quality Appraisal Tool for Studies of Diagnostic Reliability and the Guidelines for Reporting Reliability and Agreement studies. Inter-rater reliability estimates were pooled across studies using meta-analysis, and the influence of several factors (eg, imaging methods, grading scales, and occlusion rate) was tested with meta-regression. RESULTS From 1193 titles, 644 abstracts and 87 full-text versions were reviewed. Twenty-six articles met the inclusion criteria and provided 77 reliability estimates. Twenty-one different rating scales were used, and statistical analysis varied. Mean inter-rater agreement of the pooled studies was substantial (κ=0.65; 95% confidence interval, 0.60-0.69). Reliability varied significantly as a function of imaging methods, grading scales, occlusion rates, and their interaction. Observer agreement substantially increased with increasing occlusion rate in digital subtraction angiography but not in MR angiography. Reliability was higher in studies using 2- or 3-value grading scales than in studies with 4-value grading scales. CONCLUSIONS There is significant heterogeneity between studies evaluating the reliability of visual evaluation of aneurysm coiling. On the basis of our analysis, we found that the combination of magnetic resonance angiography, 3-value grading scale, and 2 trained raters seems most promising for usage as surrogate study end points.
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Affiliation(s)
- Marielle Ernst
- From the Department of Diagnostic and Interventional Neuroradiology (M.E., M.H.S., J.F.), Department of Medical Psychology (L.K.), and Department of Medical Biometry and Epidemiology (E.V.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston (A.J.Y.).
| | - Albert J Yoo
- From the Department of Diagnostic and Interventional Neuroradiology (M.E., M.H.S., J.F.), Department of Medical Psychology (L.K.), and Department of Medical Biometry and Epidemiology (E.V.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston (A.J.Y.)
| | - Levente Kriston
- From the Department of Diagnostic and Interventional Neuroradiology (M.E., M.H.S., J.F.), Department of Medical Psychology (L.K.), and Department of Medical Biometry and Epidemiology (E.V.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston (A.J.Y.)
| | - Michael H Schönfeld
- From the Department of Diagnostic and Interventional Neuroradiology (M.E., M.H.S., J.F.), Department of Medical Psychology (L.K.), and Department of Medical Biometry and Epidemiology (E.V.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston (A.J.Y.)
| | - Eik Vettorazzi
- From the Department of Diagnostic and Interventional Neuroradiology (M.E., M.H.S., J.F.), Department of Medical Psychology (L.K.), and Department of Medical Biometry and Epidemiology (E.V.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston (A.J.Y.)
| | - Jens Fiehler
- From the Department of Diagnostic and Interventional Neuroradiology (M.E., M.H.S., J.F.), Department of Medical Psychology (L.K.), and Department of Medical Biometry and Epidemiology (E.V.), University Medical Center Hamburg-Eppendorf, Hamburg, Germany; and Department of Radiology, Massachusetts General Hospital, Harvard Medical School, Boston (A.J.Y.)
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Lane A, Vivian P, Coulthard A. Magnetic resonance angiography or digital subtraction catheter angiography for follow-up of coiled aneurysms: Do we need both? J Med Imaging Radiat Oncol 2015; 59:163-9. [DOI: 10.1111/1754-9485.12288] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/25/2014] [Accepted: 12/23/2014] [Indexed: 11/29/2022]
Affiliation(s)
- Annah Lane
- Department of Medical Imaging; Royal Brisbane and Women's Hospital; Brisbane Queensland Australia
| | - Philip Vivian
- Department of Medical Imaging; Royal Brisbane and Women's Hospital; Brisbane Queensland Australia
| | - Alan Coulthard
- Department of Medical Imaging; Royal Brisbane and Women's Hospital; Brisbane Queensland Australia
- Academic Discipline of Medical Imaging; University of Queensland; Brisbane Queensland Australia
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Stalder AF, Schmidt M, Quick HH, Schlamann M, Maderwald S, Schmitt P, Wang Q, Nadar MS, Zenge MO. Highly undersampled contrast-enhanced MRA with iterative reconstruction: Integration in a clinical setting. Magn Reson Med 2014; 74:1652-60. [PMID: 25522299 DOI: 10.1002/mrm.25565] [Citation(s) in RCA: 41] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 10/17/2014] [Accepted: 11/17/2014] [Indexed: 11/06/2022]
Abstract
PURPOSE To integrate, optimize, and evaluate a three-dimensional (3D) contrast-enhanced sparse MRA technique with iterative reconstruction on a standard clinical MR system. METHODS Data were acquired using a highly undersampled Cartesian spiral phyllotaxis sampling pattern and reconstructed directly on the MR system with an iterative SENSE technique. Undersampling, regularization, and number of iterations of the reconstruction were optimized and validated based on phantom experiments and patient data. Sparse MRA of the whole head (field of view: 265 × 232 × 179 mm(3) ) was investigated in 10 patient examinations. RESULTS High-quality images with 30-fold undersampling, resulting in 0.7 mm isotropic resolution within 10 s acquisition, were obtained. After optimization of the regularization factor and of the number of iterations of the reconstruction, it was possible to reconstruct images with excellent quality within six minutes per 3D volume. Initial results of sparse contrast-enhanced MRA (CEMRA) in 10 patients demonstrated high-quality whole-head first-pass MRA for both the arterial and venous contrast phases. CONCLUSION While sparse MRI techniques have not yet reached clinical routine, this study demonstrates the technical feasibility of high-quality sparse CEMRA of the whole head in a clinical setting. Sparse CEMRA has the potential to become a viable alternative where conventional CEMRA is too slow or does not provide sufficient spatial resolution.
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Affiliation(s)
| | | | - Harald H Quick
- Erwin L. Hahn Institute for MR Imaging, University of Duisburg-Essen, Germany.,High Field and Hybrid MR Imaging, University Hospital Essen, Germany
| | - Marc Schlamann
- Department of Diagnostic and Interventional Radiology and Neuroradiology, University Hospital Essen, Germany
| | - Stefan Maderwald
- Erwin L. Hahn Institute for MR Imaging, University of Duisburg-Essen, Germany
| | | | - Qiu Wang
- Siemens Corporate Technology, Princeton, New Jersey, USA
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Detection and characterization of unruptured intracranial aneurysms: Comparison of 3T MRA and DSA. J Neuroradiol 2014; 42:162-8. [PMID: 25454398 DOI: 10.1016/j.neurad.2014.08.002] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2014] [Revised: 08/18/2014] [Accepted: 08/30/2014] [Indexed: 12/27/2022]
Abstract
PURPOSE To compare magnetic resonance angiography (MRA) at 3 Tesla (3T) and digital subtraction angiography (DSA) for the detection and characterization of unruptured intracranial aneurysms (UIA). MATERIALS AND METHODS This study has been approved by our local ethical committee. From February to August 2010, 40 consecutive patients with UIA contemporarily underwent MRA at 3T including time-of-flight (TOF-MRA) and contrast enhanced (CE-MRA) techniques and DSA. MR images were independently reviewed by 3 radiologists and DSA images were reviewed by 2 radiologists together. Interobserver and intertechnique agreements were assessed for aneurysm detection and characterization including maximal diameter, neck width and the presence of a bleb or a branch arising from the sac. RESULTS DS angiography revealed 56 aneurysms. Mean sensitivity and positive predictive value of MRA were 91.4% and 93.4% respectively. For UIA < 3 mm and those ≥ 3 mm, MRA had a mean sensitivity of 74.1% and 100% respectively. Intertechnique and interobserver agreements were substantial for the measurement of UIA maximal diameter (mean κ, 0.607 and 0.601 respectively) and were moderate and fair for neck width measurement respectively (mean κ, 0.456 and 0.285 respectively). For bleb detection, intertechnique and interobserver agreements were fair and slight respectively (mean κ, 0.312 and 0.116 respectively) whereas both were slight for detection of branches arising from the sac (mean κ, 0.151 and 0.070 respectively). CONCLUSION MR angiography at 3T has a high sensitivity for the detection of UIA. However, it remains significantly inferior to DSA for morphological characterization of UIA.
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Artefacts induced by coiled intracranial aneurysms on 3.0-Tesla versus 1.5-Tesla MR angiography—An in vivo and in vitro study. Eur J Radiol 2014; 83:811-6. [DOI: 10.1016/j.ejrad.2014.02.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2012] [Revised: 02/10/2012] [Accepted: 02/13/2012] [Indexed: 11/19/2022]
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Mortimer AM, Marsh H, Klimczak K, Joshi D, Barton H, Nelson RJ, Bradley MD, Renowden SA. Is long-term follow-up of adequately coil-occluded ruptured cerebral aneurysms always necessary? A single-center study of recurrences after endovascular treatment. J Neurointerv Surg 2014; 7:373-9. [PMID: 24721754 DOI: 10.1136/neurintsurg-2014-011152] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Accepted: 03/24/2014] [Indexed: 11/04/2022]
Abstract
PURPOSE Aneurysm recurrence following coil occlusion is well recognized. However, there is controversy as to how long these patients should be followed up after coiling to detect reopening. We aimed to identify the rate of late reopening and the risk factors for reopening in a large single-center cohort of ruptured aneurysms that appeared adequately occluded at 6 months. We also aimed to assess whether rates of recurrence have altered over time with improving coil and angiographic technology. METHODS Patients treated between 1996 and 2010 were assessed and those with both 6-month initial and subsequent long-term follow-up with either digital subtraction angiography or magnetic resonance angiography were included. Aneurysms were stratified by features such as size, neck width, anatomical location and time of treatment: 1996-2005 (cohort 1) and 2006-2010 (cohort 2). ORs for risk of recurrence were calculated for aneurysm features and rates of recurrence in each cohort were compared using a χ(2) test. RESULTS 437 patients with 458 adequately occluded aneurysms at 6 months had mean long-term follow-up of 31 months; 57 (12.4%) were large (≥ 10 mm) and 104 (22.7%) were wide-necked (>4 mm). Nine aneurysms (2%) showed significant late anatomical deterioration whereby retreatment was considered or undertaken. The risk was greater for large aneurysms (≥ 10 mm) (OR 15.61, 95% CI 3.79 to 64.33, p=0.0001) or wide-necked aneurysms (>4 mm) (OR 12.70, 95% CI 2.60 to 62.13, p=0.0017). The frequency of significant late anatomical deterioration and retreatment was also less common in those treated in cohort 2 (p<0.05). No completely occluded aneurysm at 6 months demonstrated significant late recurrence. CONCLUSIONS Most aneurysms adequately occluded at 6 months did not show evidence of late recurrence. Large and wide-neck aneurysms are, however, at greater risk of later recurrence.
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Affiliation(s)
- Alex M Mortimer
- Department of Neuroradiology, Frenchay Hospital, Bristol, UK
| | - Hannah Marsh
- Department of Neuroradiology, Frenchay Hospital, Bristol, UK
| | | | - Dhiraj Joshi
- Department of Neuroradiology, Frenchay Hospital, Bristol, UK
| | - Helena Barton
- Department of Neuroradiology, Frenchay Hospital, Bristol, UK
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Neuroimaging follow-up of cerebral aneurysms treated with endovascular techniques. RADIOLOGIA 2014. [DOI: 10.1016/j.rxeng.2014.04.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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Gemmete JJ, Elias AE, Chaudhary N, Pandey AS. Endovascular methods for the treatment of intracranial cerebral aneurysms. Neuroimaging Clin N Am 2013; 23:563-91. [PMID: 24156851 DOI: 10.1016/j.nic.2013.03.007] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
This article briefly discusses the clinical features, natural history, and epidemiology of intracranial cerebral aneurysms, along with current diagnostic imaging techniques for their detection. The main focus is on the basic techniques used in endovascular coiling of ruptured and nonruptured saccular intracranial cerebral aneurysms. After a discussion of each technique, a short review of the results of each form of treatment is given, concentrating on reported large case series. Specific complications related to the endovascular treatment of saccular intracranial aneurysms are then discussed.
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Affiliation(s)
- Joseph J Gemmete
- Division of Interventional Neuroradiology and Cranial Base Surgery, Departments of Radiology, Neurosurgery, and Otolaryngology, University of Michigan Health System, UH B1D 328, 1500 East Medical Center Drive, Ann Arbor, MI 48109-5030, USA.
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Delgado F, Saiz A, Hilario A, Murias E, San Román Manzanera L, Lagares Gomez-Abascal A, Gabarrós A, González García A. [Neuroimaging follow-up of cerebral aneurysms treated with endovascular techniques]. RADIOLOGIA 2013; 56:118-28. [PMID: 24144295 DOI: 10.1016/j.rx.2013.06.003] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2013] [Revised: 06/25/2013] [Accepted: 06/25/2013] [Indexed: 11/25/2022]
Abstract
There are no specific recommendations in clinical guidelines about the best time, imaging tests, or intervals for following up patients with intracranial aneurysms treated with endovascular techniques. We reviewed the literature, using the following keywords to search in the main medical databases: cerebral aneurysm, coils, endovascular procedure, and follow-up. Within the Cerebrovascular Disease Group of the Spanish Society of Neuroradiology, we aimed to propose recommendations and an orientative protocol based on the scientific evidence for using neuroimaging to monitor intracranial aneurysms that have been treated with endovascular techniques. We aimed to specify the most appropriate neuroimaging techniques, the interval, the time of follow-up, and the best approach to defining the imaging findings, with the ultimate goal of improving clinical outcomes while optimizing and rationalizing the use of available resources.
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Affiliation(s)
- F Delgado
- Sección de Neurorradiología, Servicio de Radiodiagnóstico, Hospital Reina Sofia, Córdoba, España
| | - A Saiz
- Sección de Neurorradiología, Servicio de Radiodiagnóstico, Hospital Universitario Central de Asturias, Oviedo, España
| | - A Hilario
- Sección de Neurorradiología, Servicio de Radiodiagnóstico, Hospital 12 de Octubre, Madrid, España
| | - E Murias
- Sección de Neurorradiología, Servicio de Radiodiagnóstico, Hospital Universitario Central de Asturias, Oviedo, España
| | - L San Román Manzanera
- Sección de Neurorradiología, Servicio de Radiodiagnóstico, Hospital Clinic, Barcelona, España
| | | | - A Gabarrós
- Servicio Neurocirugía, Hospital de Bellvitge, Barcelona, España
| | - A González García
- Sección de Neurorradiología, Servicio de Radiodiagnóstico, Hospital Universitario Virgen del Rocío, Sevilla, España.
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van Amerongen MJ, Boogaarts HD, de Vries J, Verbeek ALM, Meijer FJA, Prokop M, Bartels RHMA. MRA versus DSA for follow-up of coiled intracranial aneurysms: a meta-analysis. AJNR Am J Neuroradiol 2013; 35:1655-61. [PMID: 24008171 DOI: 10.3174/ajnr.a3700] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
MR angiography is proposed as a safer and less expensive alternative to the reference standard, DSA, in the follow-up of intracranial aneurysms treated with endovascular coil occlusion. We performed a systematic review and meta-analysis to evaluate the accuracy of TOF-MRA and contrast-enhanced MRA in detecting residual flow in the follow-up of coiled intracranial aneurysms. Literature was reviewed through the PubMed, Cochrane, and EMBASE data bases. In comparison with DSA, the sensitivity of TOF-MRA was 86% (95% CI: 82-89%), with a specificity of 84% (95% CI: 81-88%), for the detection of any recurrent flow. For contrast-enhanced MRA, the sensitivity and specificity were 86% (95% CI: 82-89%) and 89% (95% CI: 85-92%), respectively. Both TOF-MRA and contrast-enhanced MRA are shown to be highly accurate for detection of any recanalization in intracranial aneurysms treated with endovascular coil occlusion.
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Affiliation(s)
- M J van Amerongen
- From the Departments of Neurosurgery (M.J.v.A., H.D.B., J.d.V., R.H.M.A.B.)
| | - H D Boogaarts
- From the Departments of Neurosurgery (M.J.v.A., H.D.B., J.d.V., R.H.M.A.B.)
| | - J de Vries
- From the Departments of Neurosurgery (M.J.v.A., H.D.B., J.d.V., R.H.M.A.B.)
| | | | - F J A Meijer
- Radiology/Neuroradiology (F.J.A.M., M.P.), Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - M Prokop
- Radiology/Neuroradiology (F.J.A.M., M.P.), Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - R H M A Bartels
- From the Departments of Neurosurgery (M.J.v.A., H.D.B., J.d.V., R.H.M.A.B.)
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Iryo Y, Ikushima I, Hirai T, Yonenaga K, Yamashita Y. Evaluation of contrast-enhanced MR angiography in the follow-up of visceral arterial aneurysms after coil embolization. Acta Radiol 2013; 54:493-7. [PMID: 23436827 DOI: 10.1177/0284185113475920] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
BACKGROUND The placement of detachable coil has become the alternative method of treating visceral arterial aneurysms (VAAs). Imaging follow-up is necessary after coil embolization because of frequent incomplete occlusion. PURPOSE To compare contrast-enhanced magnetic resonance angiography (CE-MRA) at 3T with a reference standard of digital subtraction angiography (DSA) for the evaluation of VAAs after coil embolization. MATERIAL AND METHODS We treated 15 patients with VAA with coil embolization; eight had splenic artery aneurysms and seven had renal artery aneurysms. We packed the aneurysmal sac preserving native arterial circulation. For follow-up, all patients underwent CE-MRA at 3T and DSA. The results were classified according to coil occlusion: Class 1, complete occlusion; Class 2, residual neck; Class 3, aneurysmal filling. RESULTS CE-MRA revealed 11 complete occlusions and four residual necks. DSA follow-up showed 12 complete occlusions and three residual necks. No aneurysmal filling occurred after treatment. Comparison of CE-MRA and DSA findings showed 93% agreement (14/15). CE-MRA allowed the detection of a residual neck in one misclassified case in which DSA showed occlusion. Coil-related artifacts were minimal and did not interfere with evaluation of the occlusion status of the VAAs. CONCLUSION CE-MRA at 3T provides high-quality images equivalent to DSA for the evaluation of VAAs after coil embolization. We suggest that CE-MRA at 3T might be used as the primary method for follow-up of VAAs after coil embolization.
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Affiliation(s)
- Yasuhiko Iryo
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto
| | - Ichiro Ikushima
- Department of Radiology, Miyakonojo Medical Association Hospital, Miyakonojo, Japan
| | - Toshinori Hirai
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto
| | - Kazuchika Yonenaga
- Department of Radiology, Miyakonojo Medical Association Hospital, Miyakonojo, Japan
| | - Yasuyuki Yamashita
- Department of Diagnostic Radiology, Graduate School of Medical Sciences, Kumamoto
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Stamm AC, Wright CL, Knopp MV, Schmalbrock P, Heverhagen JT. Phase contrast and time-of-flight magnetic resonance angiography of the intracerebral arteries at 1.5, 3 and 7 T. Magn Reson Imaging 2013; 31:545-9. [DOI: 10.1016/j.mri.2012.10.023] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Revised: 09/22/2012] [Accepted: 10/30/2012] [Indexed: 10/27/2022]
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Patsalides A, Bulsara KR, Hsu DP, Abruzzo T, Narayanan S, Jayaraman MV, Duckwiler G, Klucznik RP, Kelly M, Hirsch JA, Heck D, Sunshine J, Frei D, Alexander MJ, Do HM, Meyers PM. Standard of practice: embolization of ruptured and unruptured intracranial aneurysms. J Neurointerv Surg 2013; 5:283-8. [DOI: 10.1136/neurintsurg-2012-010645] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/03/2022]
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