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Pilipenko YV, Eliava SS, Pronin IN, Okishev DN, Abramyan AA. [Completeness of brain aneurysm exclusion according to CT angiography]. ZHURNAL VOPROSY NEĬROKHIRURGII IMENI N. N. BURDENKO 2020; 84:76-85. [PMID: 33306302 DOI: 10.17116/neiro20208406176] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
OBJECTIVE To develop a classification of the completeness of brain aneurysm exclusion according to CT angiography for determining further diagnostic and curative strategy. MATERIAL AND METHODS The study included 138 patients who had 164 brain aneurysms. Clipping was carried out at the Burdenko Neurosurgery Center in 2013-2017. Titanium clips were used in 111 cases, cobalt clips - in 53 patients. RESULTS Completeness of brain aneurysm exclusion was assessed in 149 cases using CT angiography. In 15 cases, artifacts from cobalt clips impaired assessment. Total exclusion was achieved in 136 (91.3%) cases, subtotal (a remainder of residual neck) - in 10 (6.7%) cases, complete exclusion of the body and bottom (patent neck) - 2 (1.3%) patients, partial exclusion (partially patent bottom) - 1 patient (0.7%). In this series, a clip prevented complete contrast enhancement of brain aneurysm bottom in all cases. CONCLUSION CTA is a reliable method for assessing the quality of exclusion of brain aneurysm in patients with implanted titanium clips. In case of cobalt clips, stratification depending on severity of CT artifacts should be performed for data interpretation. In some cases, artifacts impair visualization of the vessels adjacent to the clips. In these patients, direct cerebral angiography or dual-energy computed tomography scanners with metal artifact suppression programs should be recommended. Follow-up is recommended for patients with remnants of residual cervix. Redo surgery is indicated for completely patent neck, as well as partial or complete contrast enhancement of aneurysm bottom.
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Affiliation(s)
| | | | - I N Pronin
- Burdenko Center of Neurosurgery, Moscow, Russia
| | - D N Okishev
- Burdenko Center of Neurosurgery, Moscow, Russia
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Walker BJ, Cox BL, Cikla U, de Bellefon GM, Rankouhi B, Steiner LJ, Mahadumrongkul P, Petry G, Thevamaran M, Swader R, Kuo JS, Suresh K, Thoma D, Eliceiri KW. An Investigation Into the Challenges of Using Metal Additive Manufacturing for the Production of Patient-Specific Aneurysm Clips. J Med Device 2019. [DOI: 10.1115/1.4043651] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Cerebral aneurysm clips are biomedical implants applied by neurosurgeons to re-approximate arterial vessel walls and prevent catastrophic aneurysmal hemorrhages in patients. Current methods of aneurysm clip production are labor intensive and time-consuming, leading to high costs per implant and limited variability in clip morphology. Metal additive manufacturing is investigated as an alternative to traditional manufacturing methods that may enable production of patient-specific aneurysm clips to account for variations in individual vascular anatomy and possibly reduce surgical complication risks. Relevant challenges to metal additive manufacturing are investigated for biomedical implants, including material choice, design limitations, postprocessing, printed material properties, and combined production methods. Initial experiments with additive manufacturing of 316 L stainless steel aneurysm clips are carried out on a selective laser melting (SLM) system. The dimensions of the printed clips were found to be within 0.5% of the dimensions of the designed clips. Hardness and density of the printed clips (213 ± 7 HV1 and 7.9 g/cc, respectively) were very close to reported values for 316 L stainless steel, as expected. No ferrite and minimal porosity is observed in a cross section of a printed clip, with some anisotropy in the grain orientation. A clamping force of approximately 1 N is measured with a clip separation of 1.5 mm. Metal additive manufacturing shows promise for use in the creation of custom aneurysm clips, but some of the challenges discussed will need to be addressed before clinical use is possible.
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Affiliation(s)
- Brandon J. Walker
- Medical Engineering, Morgridge Institute for Research, 330 N. Orchard Street, Madison, WI 53715 e-mail:
| | - Benjamin L. Cox
- Medical Engineering, Morgridge Institute for Research, 330 N. Orchard Street, Madison, WI 53715 e-mail:
| | - Ulas Cikla
- Neurological Surgery, University of Wisconsin, 1111 Highland Avenue, Madison, WI 53705 e-mail:
| | | | - Behzad Rankouhi
- Department of Mechanical Engineering, University of Wisconsin, 1513 University Avenue, Madison, WI 53705 e-mail:
| | - Leo J. Steiner
- Medical Engineering, Morgridge Institute for Research, 330 N. Orchard Street, Madison, WI 53715
- Department of Biomedical Engineering, University of Wisconsin, 1550 Engineering Drive, Madison, WI 53706 e-mail:
| | - Puwadej Mahadumrongkul
- Medical Engineering, Morgridge Institute for Research, 330 N. Orchard Street, Madison, WI 53715
- Department of Mechanical Engineering, University of Wisconsin, 1513 University Avenue, Madison, WI 53706 e-mail:
| | - George Petry
- Medical Engineering, Morgridge Institute for Research, 330 N. Orchard Street, Madison, WI 53715 e-mail:
| | - Mythili Thevamaran
- Grainger Institute for Engineering, 1550 Engineering Drive, Madison, WI 53706 e-mail:
| | - Rob Swader
- Medical Engineering, Morgridge Institute for Research, 330 N. Orchard Street, Madison, WI 53715 e-mail:
| | - John S. Kuo
- Department of Neurosurgery and Mulva Clinic for the Neurosciences, Dell Medical School, University of Texas at Austin, 1701 Trinity Street, Stop Z1500, Austin, TX 78712 e-mail:
| | - Krishnan Suresh
- Department of Mechanical Engineering, University of Wisconsin, 1513 University Avenue, Madison, WI 53706 e-mail:
| | - Dan Thoma
- Grainger Institute for Engineering, 1550 Engineering Drive, Madison, WI 53706 e-mail:
| | - Kevin W. Eliceiri
- Medical Engineering, Morgridge Institute for Research, 330 N. Orchard Street, Madison, WI 53715
- University of Wisconsin, 1111 Highland Avenue, Madison, WI 53705 e-mail:
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Vascular assessment after clipping surgery using four-dimensional CT angiography. Neurosurg Rev 2018; 42:107-114. [PMID: 29502322 DOI: 10.1007/s10143-018-0962-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2017] [Revised: 02/08/2018] [Accepted: 02/26/2018] [Indexed: 12/29/2022]
Abstract
Recent advances in computed tomography angiography (CTA) enable repeated imaging follow up for post-clipping surgery. The purpose of this study was to clarify the critical volume and configuration of the aneurysmal clip in the postoperative evaluation using volume rendering (VR) imaging, and present four-dimensional (4D)-CTA for these larger metal artifacts. A total of 44 patients with cerebral aneurysm, treated using clipping surgery, were included in this study. The metal artifact volume was assessed using CTA and the association between the type of clips and its metal artifact volume was analyzed. A VR image and a 4D-CTA were then produced, and the diagnostic accuracy of arteries around the clip or residual aneurysm on these images was evaluated. In the receiver operating characteristic (ROC) curve analysis, the cutoff value for metal artifacts was 2.32 mm3 as determined through a VR image. Patients were divided into two groups. Group 1 included patients with a simple and small clip, and group 2 included patients with multiple, large or fenestrated clips. The metal artifact volume was significantly larger in group 2, and the group incorporated the cutoff value. Post-clipping status on the VR image was significantly superior in group 1 compared with group 2. In group 2, the imaging quality of post-clipping status on 4D-CTA was superior in 92.9% of patients. The metal artifact volume was dependent on the number, size, or configuration of the clip used. In group 2, evaluation using a 4D-CTA eliminated the effect of the metal artifacts.
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Sim SY, Choi CH. Quantitative Analysis of Factors Affecting Cobalt Alloy Clip Artifacts in Computed Tomography. J Korean Neurosurg Soc 2014; 56:400-4. [PMID: 25535517 PMCID: PMC4272998 DOI: 10.3340/jkns.2014.56.5.400] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2014] [Revised: 08/07/2014] [Accepted: 08/13/2014] [Indexed: 11/27/2022] Open
Abstract
Objective Clip artifacts limit the visualization of intracranial structures in CT scans from patients after aneurysmal clipping with cobalt alloy clips. This study is to analyze the parameters influencing the degree of clip artifacts. Methods Postoperative CT scans of 60 patients with straight cobalt alloy-clipped aneurysms were analyzed for the maximal diameter of white artifacts and the angle and number of streak artifacts in axial images, and the maximal diameter of artifacts in three-dimensional (3-D) volume-rendered images. The correlation coefficient (CC) was determined between each clip artifact type and the clip blade length and clip orientation to the CT scan (angle a, lateral clip inclination in axial images; angle b, clip gradient to scan plane in lateral scout images). Results Angle b correlated negatively with white artifacts (r=-0.589, p<0.001) and positively with the angle (r=0.636, p<0.001) and number (r=0.505, p<0.001) of streak artifacts. Artifacts in 3-D images correlated with clip blade length (r=0.454, p=0.004). Multiple linear regression analysis revealed that angle b was the major parameter influencing white artifacts and the angle and number of streak artifacts in axial images (p<0.001), whereas clip blade length was a major factor in 3-D images (p=0.034). Conclusion Use of a clip orientation perpendicular to the scan gantry angle decreased the amount of white artifacts and allowed better visualization of the clip site.
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Affiliation(s)
- Sook Young Sim
- Department of Neurosurgery, Inje University Seoul Paik Hospital, Seoul, Korea
| | - Chi Hoon Choi
- Department of Radiology, National Medical Center, Seoul, Korea
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Horiuchi T, Ito K, Hongo K, Shibuya M. Mechanical evaluation of long titanium alloy clip--comparison of cobalt alloy clip. Neurol Med Chir (Tokyo) 2013; 54:176-9. [PMID: 24257493 PMCID: PMC4533422 DOI: 10.2176/nmc.oa2013-0042] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Long titanium aneurysm clips have recently been released. In the present study, comparative study of long titanium and cobalt alloy clips was performed. Two kinds of Sugita long clips (straight clips of 25- and 35-mm blade length) made of titanium and cobalt alloys were tested by measuring the closing force, the anti-scissoring torque, and the maximum opening width. There were some differences between the two materials. In the 25-mm blade length clip, closing force and maximum opening width of titanium alloy clip were greater than those of cobalt alloy clip. By contrast, the anti-scissoring torque of 35-mm blade length titanium clip was stronger than that of the cobalt. The long titanium clips would have equivalent endurance to long cobalt clip and are safe for clinical use.
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Daram SR, Tang SJ, Wu R, To SDF. Benchtop testing and comparisons among three types of through-the-scope endoscopic clipping devices. Surg Endosc 2013; 27:1521-9. [PMID: 23292554 DOI: 10.1007/s00464-012-2679-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2012] [Accepted: 10/22/2012] [Indexed: 02/07/2023]
Abstract
BACKGROUND Through-the-scope (TTS) endoscopic clipping devices are widely used. No benchtop testing or direct comparisons of these endoclips have been performed to show their rotational ability and inherent mechanical strengths during closure and after deployment. This study aimed to provide benchtop data that can be used to guide clinical applications and to promote future device research and development. METHODS Benchtop testing and comparisons were performed for three groups of TTS clips: QuickClip2 long, resolution, and instinct clips. The main outcome measurements were device-in-endoscope retroflection angles (DIERA), opening strength, "snapping" force of acute clip closure, and neoprene pulling strength. RESULTS The achievable gastroscope DIERA was 10° for QuickClip2, 3° for the resolution clip, and 10° for the instinct clip. The QuickClip and the Instinct clip rotated almost equally well under all endoscope configurations, including endoscopic retrograde cholangiopancreatography (ERCP). With or without a sheath, the resolution clip lacked the ability to rotate. During clip opening force testing (the amount of force required to force open the jaws of a deployed clip by 3.2 mm; 3.2 mm was chosen due to the standard dimension of the gauge used for the measurement), the Instinct clips were the strongest. For the Instinct clips, an opening force of 404 ± 124 g was needed to open the closed clip, and an additional 386 ± 133 g was required to open the clip jaws to 3.2 mm. In terms of snapping force during acute closure and neoprene pulling strength, the instinct and resolution clips performed almost equally. The limitations of the study were the benchtop testing and the finite sample size for closing and pulling strength comparisons. CONCLUSIONS The QuickClip2 and the Instinct clip rotate equally well under different endoscope configurations. The resolution clips lack rotational ability. The instinct clips are stronger mechanically than the other two TTS clips. Stronger clips are perhaps associated with higher therapeutic efficacy and retention rates.
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Affiliation(s)
- Sumanth R Daram
- Division of Digestive Diseases, Department of Medicine, University of Mississippi Medical Center, 2500 North State Street, Jackson, MS 39216, USA
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Horiuchi T, Rahmah NN, Yanagawa T, Hongo K. Revisit of aneurysm clip closing forces: comparison of titanium versus cobalt alloy clip. Neurosurg Rev 2012; 36:133-7; discussion 137-8. [DOI: 10.1007/s10143-012-0398-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2011] [Revised: 03/14/2012] [Accepted: 04/13/2012] [Indexed: 11/29/2022]
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HORIUCHI T, LI Y, SEGUCHI T, SATO A, AOYAMA T, HANAOKA Y, HONGO K. Clip Blade Scissoring With Titanium Bayonet Clip in Aneurysm Surgery. Neurol Med Chir (Tokyo) 2012; 52:84-6. [DOI: 10.2176/nmc.52.84] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Affiliation(s)
| | - Yuhui LI
- Department of Neurosurgery, Shinshu University School of Medicine
| | | | - Atsushi SATO
- Department of Neurosurgery, Ina Central Hospital
| | | | | | - Kazuhiro HONGO
- Department of Neurosurgery, Shinshu University School of Medicine
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Horiuchi T, Hongo K, Shibuya M. Scissoring of cerebral aneurysm clips: mechanical endurance of clip twisting. Neurosurg Rev 2011; 35:219-24; discussion 224-5. [DOI: 10.1007/s10143-011-0347-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2011] [Revised: 05/31/2011] [Accepted: 07/03/2011] [Indexed: 11/24/2022]
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Zachenhofer I, Cejna M, Schuster A, Donat M, Roessler K. Image quality and artefact generation post-cerebral aneurysm clipping using a 64-row multislice computer tomography angiography (MSCTA) technology. Clin Neurol Neurosurg 2010; 112:386-91. [DOI: 10.1016/j.clineuro.2010.02.001] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2009] [Revised: 09/07/2009] [Accepted: 02/03/2010] [Indexed: 11/17/2022]
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Krammer MJ, Lumenta CB. The new aneurysm clip system for particularly complex aneurysm surgery: technical note. Neurosurgery 2010; 66:336-8. [PMID: 20489528 DOI: 10.1227/01.neu.0000369644.26132.56] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
BACKGROUND Currently, there is an ongoing debate regarding the best treatment option for ruptured aneurysms. The International Subarachnoid Aneurysm Trial study suggests that an endovascular procedure is the best treatment. In some complex cases, or in patients with an additional large intracerebral hemorrhage, aneurysms require further microsurgical clipping. OBJECTIVE We introduce a new clip system to improve clipping procedures in especially complex aneurysms. METHODS The inverted opening mechanism of the clip in combination with the special clip applier provides the surgeon with a good overview in the operating field. The new design also enables a wider opening of the clip jaws in contrast to all other well-known titanium aneurysm clips. This should provide a better and safer application and decrease the danger of premature rupture. RESULTS From January 2006 to July 2008, 55 aneurysms were clipped in 45 patients. The most common aneurysm location was the anterior communicating artery (20 patients) followed by the M1 segment of the middle cerebral artery (16 patients). Four patients had 2, one had 3, and one had 5 aneurysms. Two clipping procedures were performed for an arteriovenous malformation-associated aneurysm. All aneurysms were clipped without any technical complication. CONCLUSION The use of the new clip system, especially in complex aneurysm surgery, has potential benefits because of the better surgical vision during clip application and the wider opening of the clip jaws. It is easy to handle and compatible with magnetic resonance imaging.
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Affiliation(s)
- Matthias J Krammer
- Department of Neurosurgery, Bogenhausen Academic Teaching Hospital, Technical University of Munich, Munich, Germany
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Pechlivanis I, Koenen D, Engelhardt M, Scholz M, Koenig M, Heuser L, Harders A, Schmieder K. Computed tomographic angiography in the evaluation of clip placement for intracranial aneurysm. Acta Neurochir (Wien) 2008; 150:669-76. [PMID: 18493701 DOI: 10.1007/s00701-008-1515-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2007] [Accepted: 11/13/2007] [Indexed: 11/26/2022]
Abstract
BACKGROUND Computed tomographic angiography (CTA) has been shown to reliably detect aneurysms pre-operatively. The aim of this study was to compare the ability of post-operative CTA to detect aneurysmal remnants in connection with clip placement compared with digital subtraction angiography (DSA). Furthermore, special attention was paid to identifying factors influencing the image quality of CTA. METHOD Between January 2005 and January 2006 a total of 76 patients with intracranial aneurysms were treated in our department. Thirty-two patients with a total of 33 clipped aneurysm were included in this study. All patients underwent CTA and DSA after surgery. Two investigators, each blinded to the classifications of the other, assessed image quality and clip placement. FINDINGS In three patients aneurysmal remnants could be detected with CTA and DSA. One 2-mm aneurysmal remnant was not clearly identified on CTA; two small (<2-mm) aneurysmal remnants were definitely not seen on CTA. A single titanium clip was used for aneurysmal clipping in 26 patients, two clips were needed in six patients and one aneurysm required three clips being used. Overall, use of one titanium clip tended to result in better image quality. In addition, clip-gantry angles between 30 degrees and 60 degrees tended to yield better image quality. CONCLUSION Post-operatively, CTA can be recommended as a reliable non-invasive diagnostic tool only with optimal image quality and with this criterion up to 66% of the aneurysms can be evaluated. Titanium artefacts, especially in the important zone (<2 mm) around the clip in which small aneurysmal remnants can occur, can render adequate evaluation impossible. CTA image quality depends on the number of titanium clips used, but clip-gantry-angle does not significantly influence the image quality.
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Affiliation(s)
- I Pechlivanis
- Department of Neurosurgery, Ruhr-University of Bochum, Knappschaftskrankenhaus Bochum-Langendreer, Bochum, Germany.
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Sagara Y, Kiyosue H, Hori Y, Sainoo M, Nagatomi H, Mori H. Limitations of three-dimensional reconstructed computerized tomography angiography after clip placement for intracranial aneurysms. J Neurosurg 2005; 103:656-61. [PMID: 16266048 DOI: 10.3171/jns.2005.103.4.0656] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Object. The authors compared the usefulness of three-dimensional (3D) reconstructed computerized tomography (CT) angiography with 3D digital subtraction (DS) angiography in assessing intracranial aneurysms after clip placement. A retrospective review of clinical cases was performed.
Methods. Between May 2001 and May 2003, 17 patients with a total of 20 intracranial aneurysms underwent 3D CT and 3D DS angiography following clip placement. The authors assessed the presence or absence of residual aneurysm necks and stenoocclusive changes in the parent artery and the neighboring artery. The efficacy of CT angiographic visualization was also evaluated.
In 12 of the 20 aneurysms, both 3D modalities similarly demonstrated the residual aneurysm neck and stenoocclusive changes in the parent artery and neighboring artery. Three-dimensional CT angiography failed to demonstrate three of the aneurysms, and the studies were not considered suitable for evaluation because of the presence of metallic artifacts. In the remaining five studies, the 3D CT angiograms did not effectively demonstrate the neighboring and parent arteries. The detectability of residual aneurysm necks was correlated with the clip material and with the number of clips applied.
Conclusions. Three-dimensional DS angiography is still necessary in cases involving multiple clips or with cobalt alloy clips because the clips appear as metal artifacts on 3D CT angiography.
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Affiliation(s)
- Yoshiko Sagara
- Department of Radiology, Faculty of Medicine, Oita University, Japan.
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Papadopoulos MC, Apok V, Mitchell FT, Turner DP, Gooding A, Norris J. Endurance of aneurysm clips: mechanical endurance of Yaşargil and Spetzler titanium aneurysm clips. Neurosurgery 2004; 54:966-70; discussion 970-2. [PMID: 15046665 DOI: 10.1227/01.neu.0000116140.53925.03] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2003] [Accepted: 11/13/2003] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE To determine whether repeated use weakens titanium aneurysm clips, making them unsafe for clinical use. METHODS Nine Yaşargil (titanium alloy) and five Spetzler (pure titanium) clips were subjected to clinically relevant maneuvers, and the effects on the closing force were assessed. Clips were considered unsafe if 1) the blades crossed, 2) the clips failed to close completely, or 3) the blood pressure could open them. RESULTS Yaşargil and Spetzler clips significantly (P < 0.01 for both) weakened, by 18.9% and 26.1%, respectively, after 10 minutes of sustained maximal opening. After 100 open-close cycles, Spetzler clips showed no change in closing force, but the closing force of Yaşargil clips decreased significantly (P < 0.01), by a further 12.0%. CONCLUSION Repeated use weakens Spetzler and Yaşargil clips. All Spetzler and all but one Yaşargil clips were deemed safe for clinical use at the end of the experiments.
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Affiliation(s)
- Marios C Papadopoulos
- Department of Neurosurgery, Hurstwood Park Neurological Centre, Princess Royal Hospital, Haywards Heath, West Sussex, England, U.K
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Anzai Y, Minoshima S. [Standardization of MR--safety, sequences, and reporting; neuroradiology practice in US]. Nihon Hoshasen Gijutsu Gakkai Zasshi 2004; 60:762-71. [PMID: 15220862 DOI: 10.6009/jjrt.kj00000922475] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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