Prediction of Venous Trans-Stenotic Pressure Gradient Using Shape Features Derived From Magnetic Resonance Venography in Idiopathic Intracranial Hypertension Patients

OBJECTIVE

Idiopathic intracranial hypertension (IIH) is a condition of unknown etiology associated with venous sinus stenosis. This study aimed to develop a magnetic resonance venography (MRV)-based radiomics model for predicting a high trans-stenotic pressure gradient (TPG) in IIH patients diagnosed with venous sinus stenosis.

MATERIALS AND METHODS

This retrospective study included 105 IIH patients (median age [interquartile range], 35 years [27-42 years]; female:male, 82:23) who underwent MRV and catheter venography complemented by venous manometry. Contrast enhanced-MRV was conducted under 1.5 Tesla system, and the images were reconstructed using a standard algorithm. Shape features were derived from MRV images via the PyRadiomics package and selected by utilizing the least absolute shrinkage and selection operator (LASSO) method. A radiomics score for predicting high TPG (≥ 8 mmHg) in IIH patients was formulated using multivariable logistic regression; its discrimination performance was assessed using the area under the receiver operating characteristic curve (AUROC). A nomogram was constructed by incorporating the radiomics scores and clinical features.

RESULTS

Data from 105 patients were randomly divided into two distinct datasets for model training (n = 73; 50 and 23 with and without high TPG, respectively) and testing (n = 32; 22 and 10 with and without high TPG, respectively). Three informative shape features were identified in the training datasets: least axis length, sphericity, and maximum three-dimensional diameter. The radiomics score for predicting high TPG in IIH patients demonstrated an AUROC of 0.906 (95% confidence interval, 0.836-0.976) in the training dataset and 0.877 (95% confidence interval, 0.755-0.999) in the test dataset. The nomogram showed good calibration.

CONCLUSION

Our study presents the feasibility of a novel model for predicting high TPG in IIH patients using radiomics analysis of noninvasive MRV-based shape features. This information may aid clinicians in identifying patients who may benefit from stenting.

A study of the prognostic significance of platelet distribution width, mean platelet volume, and plateletcrit in cerebral venous sinus thrombosis

Objectives

Platelets play a key role in thrombus formation and propagation and are thus implicated in the pathogenesis and morbidity of cerebral venous sinus thrombosis (CVST). A whole blood count can be used to objectively measure platelet function through platelet indices, namely, platelet distribution width (PDW), mean platelet volume (MPV), and plateletcrit. This study examined how platelet indices (PDW,MPV, and plateletcrit) affect the CVST severity and functional outcome.

Materials and Methods

In this prospective, longitudinal, and observational study, 66 patients with CVST from a tertiary care referral center were enrolled. A complete blood count including platelet indices was obtained using an automated hematology analyzer. Patients with and without parenchymal abnormalities on brain imaging were classified as having severe and non-severe CVST, respectively. The modified Rankin Scale (mRS) was used to examine functional outcomes at admission and after 90 days. The patients were categorized into low mRS (0-1) and high mRS (2-6) functional groups.

Results

The patients with severe CVST were older (P < 0.05) and exhibited abnormally large PDW (P < 0.05) which were statistically significant. Severe CSVT also had poor functional outcome score both at admission (P < 0.05) and 90 days later (P < 0.05) which were statistically significant. Multiple logistic regression analysis concluded age and PDW as the independent predictors of severe CVST (P < 0.05). In receiver operating characteristic curve analysis, a cutoff value of 16.5 for PDW could predict CVST severity (P < 0.05). Patients with high mRS scores at admission had significantly larger PDW. At 90 days, no association was noted between PDW and mRS scores. MPV and plateletcrit levels were similar in both the severe and non-severe CVST groups and exerted no effect on functional outcomes. PDW was significantly and inversely related to plateletcrit (P < 0.05).

Conclusion

Severe CVST and PDW had a positive correlation. During the early phases of admission, PDW levels above a particular threshold were associated with poor functional outcomes; however, no such association was observed after 90 days. MPV and plateletcrit exerted no effect on CVST severity and prognosis.

Prevalence of cerebral sinovenous thrombosis in abusive head trauma

BACKGROUND

Cerebral sinovenous thrombosis (CSVT) has been proposed in legal settings to be an atraumatic mimic of abusive head trauma (AHT).

OBJECTIVE

The objective of this study was to determine the prevalence of CSVT and subdural hemorrhage (SDH) in a large AHT population.

MATERIALS AND METHODS

This retrospective cohort study measured the prevalence of CSVT and SDH on magnetic resonance venograms in 243 patients diagnosed with AHT at a single center. We also reported additional intra- and extracranial injuries, head injury severity and length of hospital stay.

RESULTS

Among 243 patients diagnosed with AHT, 7% (16/243) had CSVT. SDH was present in 94% (15/16) of the CSVT cases. Cytotoxic edema and subarachnoid hemorrhage were in 88% (14/16) and 69% (11/16) of the CSVT cases, respectively. Extracranial signs of abuse were also in 100% (16/16) of the patients with CSVT. Critical to maximal head injury severity (abbreviated injury scale >=5) was in 75% (12/16) of the CSVT population vs. 33% (82/243) in the total AHT population. Length of hospital and pediatric intensive care unit stay was greater in those with CSVT (10 vs. 21.9 and 3.5 vs. 7.3 days).

CONCLUSION

These findings suggest that CSVT is uncommon in AHT and is associated with additional traumatic injuries and greater injury severity.

Efficacy of Dural Sinus Quantitative Measurements in Idiopathic Intracranial Hypertension : A Practical Diagnostic Feature

BACKGROUND AND PURPOSE

This study aimed to investigate the potential contribution of quantitative measurements of dural venous sinuses to the diagnosis of idiopathic intracranial hypertension (IIH) and the relationship between IIH and dural venous sinus dimensions on 3D post-gadolinium T1-weighted magnetic resonance (MR) images.

MATERIAL AND METHODS

A total of 129 individuals (57 IIH patients and 72 controls) who complained of headache and underwent both magnetic resonance venography (MRV) and precontrast/postcontrast 3D T1-weighted MR imaging between 2018 and 2021 were included in this retrospective study. Dural venous sinus and jugular vein diameters were measured in all cases using post-gadolinium 3D T1 TFE images. The presence of transverse sinus (TS) hypoplasia and occipital sinus variation, the number and size of arachnoid granulations in the TS, and the presence of brain parenchymal herniation were also evaluated. Cut-off values that maximized accurate diagnosis of IIH were established on the receiver operating characteristic curve. The sensitivity and specificity of the diagnosis of IIH based on quantitative measurements of the dural sinus were calculated.

RESULTS

The ratios of the maximum to minimum TS diameters and the minimum TS diameters to minimum sigmoid sinus (SS) diameters were significantly higher in IIH patients than in the control group (p < 0.001). The diagnostic sensitivity and specificity values of TS_max/TS_min and TS_{min sum}/SS_{min sum} parameters for the detection of IIH were 84.2%, 84.7% and 83.3%, 84.2%, respectively.

CONCLUSION

Practical measurements from multiplanar T1 sequences can be useful for both quantitative assessment and overcoming misinterpretation due to anatomical variation.

Pediatric magnetic resonance angiography: to contrast or not to contrast

Magnetic resonance (MR) angiography and MR venography imaging with contrast and non-contrast techniques are widely used for pediatric vascular imaging. However, as with any MRI examination, imaging the pediatric population can be challenging because of patient motion, which sometimes requires sedation. There are multiple benefits of non-contrast MR angiographic techniques, including the ability to repeat sequences if motion is present, the decreased need for sedation, and avoidance of potential risks associated with gadolinium administration and radiation exposure. Thus, MR angiography is an attractive alternative to CT or conventional catheter-based angiography in pediatric populations. Contrast-enhanced MR angiographic techniques have the advantage of increased signal to noise. Blood pool imaging allows long imaging times that result in high-spatial-resolution imaging, and thus high-quality diagnostic images. This article outlines the technique details, indications, benefits and downsides of non-contrast-enhanced and contrast-enhanced MR angiographic techniques to assist in protocol decision-making.

Non-contrast magnetic resonance angiography/venography techniques: what are my options?

Non-contrast magnetic resonance (MR) angiography and MR venography techniques are gaining popularity for vascular imaging because they are faster, more forgiving and less costly compared with contrast-enhanced MR angiography. Non-contrast MR angiography also avoids gadolinium deposition, which is especially important in imaging children. Non-contrast MR angiography has an array of specific applications for numerous clinical indications. This review summarizes the non-contrast MR angiography methods and their relative advantages and disadvantages. The paper also guides the reader on which technique to consider when determining the optimal imaging modality for each individual patient.

High-resolution three‑dimensional contrast‑enhanced magnetic resonance venography in children: comparison of gadofosveset trisodium with ferumoxytol

BACKGROUND

Gadofosveset is a gadolinium-based blood pool contrast agent that was approved by the United States Food and Drug Administration in 2008. Its unanticipated withdrawal from production in 2016 created a void in the blood pool agent inventory and highlighted the need for an alternative agent with comparable imaging properties.

OBJECTIVE

The purpose of our study is to compare the diagnostic image quality, vascular contrast-to-noise ratio (CNR) and temporal signal characteristics of gadofosveset trisodium and ferumoxytol at similar molar doses for high-resolution, three-dimensional (3-D) magnetic resonance (MR) venography in children.

MATERIALS AND METHODS

The medical records and imaging data sets of patients who underwent high-resolution 3-D gadofosveset-enhanced MR venography (GE-MRV) or ferumoxytol-enhanced MR venography (FE-MRV) were retrospectively reviewed. Two groups of 20 pediatric patients (age- and weight-matched with one patient common to both groups; age range: 2 days-15 years) who underwent high-resolution 3-D GE-MRV or FE-MRV at similar molar doses were identified and analyzed. Qualitative analysis of image quality and vessel definition was performed by two blinded pediatric radiologists. Interobserver agreement was assessed with the AC1 (first-order agreement coefficient) statistic. Signal-to-noise ratio (SNR) and CNR of the inferior vena cava and aorta were measured in the steady-state venous phase. Medical records were retrospectively reviewed for any adverse reactions associated with either contrast agent.

RESULTS

Measured SNR and CNR of the inferior vena cava were higher for FE-MRV than GE-MRV (P = 0.034 and P < 0.001, respectively). The overall image quality score and individual vessel scores of FE-MRV were equal to or greater than GE-MRV (P = 0.084), with good interobserver agreement (AC1 = 0.657). The venous signal on FE-MRV was stable over the longest interval measured (1 h, 13 min and 46 s), whereas venous signal on GE-MRV showed more variability and earlier loss of signal. No adverse reactions were noted in any patient with either contrast agent.

CONCLUSION

Ferumoxytol produces more uniform and stable enhancement throughout the entire venous circulation in children than gadofosveset, offering a wider time window for optimal image acquisition. FE-MRV offers a near-ideal approach to high-resolution venography in children at all levels of anatomical complexity.

Case Report: Ulcerative Colitis with Multiple Dural Venous Thrombosis

Background Cerebral sinus vein thrombosis (CVT) is a rare but serious complication associated with ulcerative colitis (UC), an idiopathic autoimmune inflammatory disease of the gastrointestinal tract. Management approaches for CVT remain unclear but may include anticoagulation and surgical thrombectomy. Herein, we report a case of a 23-year-old male who developed CVT with a history of UC. The patient was presented to Howard University Hospital when he slipped and fell. On arrival at the hospital, he complained of a headache with an aching sensation, associated with light/sound sensitivity. The patient had a history of uncontrolled UC. He had positive bloody diarrhea, lower abdominal pain, but denied any other neurological deficit. Computed tomography of the head showed left frontoparietal lobe hypodensities. Neurological exam was nonfocal. Vital signs were within normal range, but the patient experienced some memory loss and personality changes. Subsequent diagnosis of CVT was made with magnetic resonance angiography and magnetic resonance venography. Immediate treatment with low-molecular-weight intravenous heparin (18 IU/kg) was introduced. His UC was managed with methylprednisolone (60 mg IV daily), proton pump inhibitors, mesalamine, ciprofloxacin, and metronidazole. His condition gradually improved. On discharge, he was prescribed prednisone, azathioprine for his UC, levetiracetam for seizure, and warfarin with an INR goal of 2-3. In conclusion, the sudden onset and/or acute worsening of neurological status such as headache and mental confusion in a patient with UC should alert the treating physician about the possibility of CVT so that timely intervention could be employed to prevent disabling and potentially lethal sequelae of this disease.

Non-enhanced multimodal magnetic resonance imaging in assessment of iliac vein obstruction with or without thrombosis

OBJECTIVE

To evaluate the diagnostic accuracy of a contrast-free multimodal magnetic resonance (MR) protocol (including M2DIPEAR, THRIVE, BTFE-SPAIR, and FLAIR sequences) in the detection of iliac vein obstruction with or without thrombosis.

MATERIALS AND METHODS

From May 1st, 2015, to May 1st, 2016, a total of 73 patients (aged 51.33 ± 4.21 years) who received both digital subtraction angiography (DSA) and the multimodal MR imaging were included. The protocol of the multimodal MR included M2DIPEAR and BTFE-SPAIR for presenting iliac vein obstruction, and THRIVE and FLAIR for revealing the co-existed thrombosis. Three observers who were blinded to clinical and DSA results independently analyzed all multimodal MR datasets. Per-patient evaluations on presence or absence of iliac vein obstruction were performed to calculate the diagnostic performance of MR imaging (DSA regarded as gold reference) in terms of overall accuracy, sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV). Capability to display the co-existing venous thrombus was also evaluated per-MR sequence using a 3-point scale system.

RESULTS

Iliac vein obstruction was depicted with DSA in 64 patients. In per-patient evaluation, the multimodal MR imaging yielded accuracy of 95.9% (70/73), sensitivity of 96.9% (62/64), specificity of 88.9% (8/9), positive predictive value of 98.4% (62/63), and negative predictive value of 80% (8/10), respectively. In the multimodal MR sequences, balanced turbo field echo-spectral attenuated inversion recovery (BTFE-SPAIR) sequence was superior to other sequences in depicting the iliac vein configuration, but fluid attenuated inversion recovery (FLAIR) and T1 high-resolution isovolumetric examination (THRIVE) seemed superior in detecting co-existing venous thrombosis.

CONCLUSIONS

M2DIPEAR and BTFE-SPAIR sequence can reveal iliac vein obstruction while THRIVE and FLAIR can detect the co-existed thrombosis. The proposed multimodal MR protocol can accurately depict the iliac vein obstruction and accurately detect the co-existing venous thrombosis comparable with that of DSA.

Artifact quantification of venous stents in the MRI environment: Differences between braided and laser-cut designs

PURPOSE

To quantify B₀- and B₁-induced imaging artifacts of braided venous stents and to compare the artifacts to a set of laser-cut stents used in venous interventions.

METHODS

Three prototypes of braided venous stents with different geometries were tested in vitro. B₀ field distortion maps were measured via the frequency shift Δf using multi-echo imaging. B₁ distortions were quantified using the double angle method. The relative amplitudes B₁^rel were calculated to compare the intraluminal alteration of B₁. Measurements were repeated with the stents in three different orientations: parallel, diagonal and orthogonal to B₀.

RESULTS

At 1.5 T, the braided stents induced a maximum frequency shift of Δfx<100Hz. Signal voids were limited to a distance of 2 mm to the stent walls at an echo time of 3 ms. No substantial difference in the B₀ field distortions was seen between laser-cut and braided venous stents. B₁^rel maps showed strongly varying distortion patterns in the braided stents with the mean intraluminal B₁^rel ranging from 63±18% in prototype 1 to 98±38% in prototype 2. Compared to laser-cut stents the braided stents showed a 5 to 9 times higher coefficient of variation of the intraluminal B₁^rel.

CONCLUSION

Braided venous stent prototypes allow for MR imaging of the intraluminal area without substantial signal voids due to B₀-induced artifacts. Whereas B₁ is attenuated homogeneously in laser-cut stents, the B₁ distortion in braided stents is more inhomogeneous and shows areas with enhanced amplitude. This could potentially be used in braided stent designs for intraluminal signal amplification.

Non-contrast magnetic resonance venography with Inhance 3D Velocity: diagnostic performance for intracranial venous thrombosis

PURPOSE

The aim of this study was to evaluate the diagnostic performance of Inhance 3D Velocity (I3DV) in intracranial venous thrombosis and investigate the possible impact of venous sinus hypoplasia/aplasia on false thrombosis diagnosis made with I3DV.

METHODS

This study included 540 patients. Contrast-enhanced magnetic resonance venography combined with conventional sequences was considered the gold standard test (GST), while I3DV was considered as diagnostic test. We accessed the diagnostic success of I3DV for intracranial venous thrombosis detection, thrombosed vessel identification, and total/partial thrombus distinction. The possible relationship between false-positive thrombus diagnosed by I3DV and venous sinus hypoplasia or aplasia diagnosed by GST was investigated.

RESULTS

The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of I3DV in the detection of intracranial venous thrombosis were 95.7%, 92.1%, 64.1%, 99.3%, and 92.6%, respectively. A significant association was observed between I3DV and GST in terms of thrombosis detection and total/partial thrombus distinction (p < 0.001). A significant relationship was observed between false-positive thrombosis diagnosis in I3DV and hypoplasia in the left transverse sinus (p < 0.001).

CONCLUSION

Intracranial venous thrombosis may be diagnosed faster and more accurately than traditional phase contrast magnetic resonance angiography in I3DV. This technique can be used in situations where contrast medium application is contraindicated. As in other non-contrast magnetic resonance venography techniques, left transverse sinus hypoplasia can be diagnosed as a thrombosed vessel in I3DV.

A Simple Surgical Technique for Pediatric Sinus Pericranii: Intraoperative Manual Compression of a Major Shunting Point

INTRODUCTION

Sinus pericranii is a vascular anomaly with extra- and intracranial venous connections. Sinus pericranii is categorized into 2 groups according to its contribution to the normal venous circulation. The accessory type sinus pericranii, which does not contribute to the normal major venous circulation, can be managed. Despite several proposed operative maneuvers, a standardized technique is yet to be established to control intraoperative bleeding.

CASE PRESENTATION

A 2-week-old neonate underwent examination of a subcutaneous mass in the parieto-occipital region. The subcutaneous mass had a major venous connection to the superior sagittal sinus on ultrasonography. The subcutaneous mass was partially thrombolized on magnetic resonance imaging and was minimally enhanced on computed tomography venography. The subcutaneous mass seemed not to contribute to the normal venous circulation. Surgical removal of the subcutaneous mass was performed due to its increased size at the age of 1 year and 3 months. While subcutaneous mass was detached from the scalp, the major venous connection was manually compressed, and minor venous connections were easily detected. The intraoperative bleeding was controllable. The pathological diagnosis was sinus pericranii. The patient is now followed up in the outpatient clinic. No recurrence was seen 18 months after the surgery.

DISCUSSION/CONCLUSION

Intraoperative hemostasis is essential while sinus pericranii is detached from the cranium. Hemostatic agents such as bone wax or absorbable gelatin and heat coagulation seem to be useful. However, complicative hemorrhage concerning to the preceded technique has been also reported. As seen in our case, to detect minor shunting points between the sinus pericranii and the intracranial veins, the major venous connection was manually compressed. Intraoperative manual compression of a major venous connection of sinus pericranii can be an option to manage intraoperative bleeding.

Two cases of persistent falcine and occipital sinuses

BACKGROUND

The coexistence of falcine and occipital sinuses is rare and its natural course has not been reported.

CASE REPORTS

Two patients with persistent falcine and occipital sinuses are described. Both patients had straight sinuses. In one, both the transverse and sigmoid sinuses were hypoplastic and the patient had an acquired Chiari I malformation. The other patient had no other venous anomalies and had a normal posterior cranial fossa.

CONCLUSION

The coexistence of falcine and occipital sinuses can lead to an acquired Chiari I malformation. These cases suggest the importance of checking other venous and brain anomalies in this situation.

Pearls and Pitfalls in the Magnetic Resonance Diagnosis of Dural Sinus Thrombosis: A Comprehensive Guide for the Trainee Radiologist

Dural sinus thrombosis (DST) is a potentially fatal neurological condition that can be reversed with early diagnosis and prompt treatment. Non-enhanced CT scan is often the first imaging investigation in patients presenting with acute neurological symptoms; however, its poor sensitivity in detecting DST is a major drawback. Magnetic resonance (MR) imaging offers multiple advantages such as excellent contrast resolution and unenhanced venography possibilities, making it the mainstay in the non-invasive diagnosis of DST. However, physiological variations, evolution of thrombi, and incorrect selection/application of MR techniques can lead to false positive and false negative interpretations impacting patient management and outcome. This article discusses the MR techniques useful to diagnose DST and describes pitfalls, with troubleshooting methods, to ensure an accurate diagnosis. We have used multiple diagrammatic illustrations and MR images to highlight pertinent take-home points and to serve as an easy guide for day-to-day clinical practice.

Detecting small conflicting drainages with contrast-enhanced magnetic resonance venography for surgical planning: a technical description and quantified analysis

BACKGROUND

Recent studies have shown the challenges involved in detecting small conflicting vessels (1.0-1.5 mm) on contrast-enhanced (CE) T1 images during stereoelectroencephalography (SEEG) planning. Improving the resolution of non-invasive approaches to identify these vessels is possible and important. We present a superior sagittal sinus mapping-based CE-magnetic resonance venography (CE-MRV) protocol calibrated by craniotomies.

METHOD

Seven patients with epileptic symptoms who received craniotomy were enrolled. CE-MRV was acquired with a bolus mapping of the superior sagittal sinus. Together with the T1 image, 3D veins and the brain surface were visualized. The resolution of the CE-MRV was quantified by measuring the diameter of superficial drainages after exposure of the brain surface during craniotomy.

RESULTS

A total of 37 superficial drainages were exposed in the bone windows. CE-MRV visualized all these drainages. On average, one superficial drainage could be found in every 13.2 mm diameter of the bone window. The boundary resolution of the CE-MRV was 0.58-0.8 mm in vessel diameter, while drainages larger than 0.8 mm were visualized consistently.

CONCLUSIONS

The resolution of the CE-MRV in the present study met the requirement for detection of small conflicting vessels during SEEG planning. The visualized venous landmarks could be used for visual guidance to the surgical zone. As a non-invasive approach, CE-MRV is practical to use in the clinical setting.

Review of imaging and endovascular intervention of iliocaval venous compression syndrome

Iliocaval venous compression syndrome (ICS) is the extrinsic compression of the common iliac vein by the overlying iliac artery against the vertebra. Chronic compression can lead to venous stenosis and stasis, which manifests as chronic venous disease and treatment resistance. Therefore, early recognition of ICS and prompt treatment are essential. Clinical presentations of ICS can be ambiguous and diagnosis requires a high index of suspicion with the relevant imaging studies. The initial imaging test is typically a Duplex ultrasound for vessel assessment and pelvic ultrasound to exclude a compressive mass, which is followed by computed tomography (CT) or magnetic resonance (MR) venography. CT and MRI can identify the anatomical causes for venous compression. In patients with high clinical suspicion for ICS, negative findings on CT and MR venography would still warrant further investigations. Definitive diagnosis can be established using catheter-based venography complemented with intravascular ultrasonography but the nature of their invasiveness limits its utility as a routine imaging modality. In this review paper, we will discuss the evidence, utility and limitations of the existing imaging modalities and endovascular intervention used in the management of ICS.

Magnetic resonance imaging and magnetic resonance venography features in heat stroke: a case report

Background

Heat stroke (HS) is a critical illness that can cause multiple organ dysfunction, including damage to the central nervous system (CNS), which can be life-threatening in severe cases. Brain lesions in patients with HS who present with CNS damage have been rarely reported before, and they usually vary in different cases, hence, patients with such lesions may present a clinical challenge in terms of diagnosis and management. Cerebral venous thrombosis (CVT) is a rare cause of stroke that mostly affects young individuals and children. The pathogenesis of brain damage caused by HS is complex, and CVT may be involved in the pathogenesis of HS with CNS damage. In this manuscript, we have reported a case of a patient with HS having CVT with symmetrical lesions in the bilateral putamen, posterior limb of the internal capsule, external capsule, insular lobe, and subcortical white matter in the brain.

Case presentation

We encountered a 48-year-old man who presented with HS in the summer season. During admission, he had a high body temperature and was in coma and shock. Then, he developed rhabdomyolysis syndrome, acute kidney and liver damage, electrolyte imbalance, and acid–base balance disorders, and his D-dimer level was elevated. After several days of anti-shock treatment, the patient’s level of consciousness improved. However, he experienced a decline in vision. Cerebral magnetic resonance imaging (MRI) showed symmetrical lesions in the bilateral posterior limb of the internal capsule, putamen, external capsule, insula, and subcortical white matter, and cerebral magnetic resonance venography (MRV) showed the development of CVT. Therefore, anti-coagulation treatment was provided. After timely clinical intervention, the symptoms of the patient gradually improved.

Conclusions

This case showed that HS can cause CVT. Therefore, cerebral MRI findings in HS must be assessed; in addition, early MRV can help in the diagnosis of the disease, which can effectively improve prognosis.

MR venography using time-resolved imaging in interventional management of pelvic venous insufficiency

PURPOSE OF REVIEW

To evaluate the utility of magnetic resonance venography with time-resolved imaging (MRV TRI) in the diagnosis of pelvic vein insufficiency (PVI).

RECENT FINDINGS

A retrospective single-center review of N = 17 consecutive patients who underwent pelvic MRI for the assessment of PVI was performed. N = 8/17 (47%) studies were positive for PVI. TRI imaging demonstrated N = 6/8 patients with Grade 0-3 PVI and N = 2/8 patients with May-Thurner Syndrome. N = 4/8 patients underwent elective endovascular management, all of which were technically successful. In the assessment of PVI, MRV TRI provides a dynamic assessment of venous insufficiency, serving as an adjunct to the imaging diagnosis of this pathology.

High resolution, 3-dimensional Ferumoxytol-enhanced cardiovascular magnetic resonance venography in central venous occlusion

BACKGROUND

Although cardiovascular magnetic resonance venography (CMRV) is generally regarded as the technique of choice for imaging the central veins, conventional CMRV is not ideal. Gadolinium-based contrast agents (GBCA) are less suited to steady state venous imaging than to first pass arterial imaging and they may be contraindicated in patients with renal impairment where evaluation of venous anatomy is frequently required. We aim to evaluate the diagnostic performance of 3-dimensional (3D) ferumoxytol-enhanced CMRV (FE-CMRV) for suspected central venous occlusion in patients with renal failure and to assess its clinical impact on patient management.

METHODS

In this IRB-approved and HIPAA-compliant study, 52 consecutive adult patients (47 years, IQR 32-61; 29 male) with renal impairment and suspected venous occlusion underwent FE-CMRV, following infusion of ferumoxytol. Breath-held, high resolution, 3D steady state FE-CMRV was performed through the chest, abdomen and pelvis. Two blinded reviewers independently scored twenty-one named venous segments for quality and patency. Correlative catheter venography in 14 patients was used as the reference standard for diagnostic accuracy. Retrospective chart review was conducted to determine clinical impact of FE-CMRV. Interobserver agreement was determined using Gwet's AC1 statistic.

RESULTS

All patients underwent technically successful FE-CMRV without any adverse events. 99.5% (1033/1038) of venous segments were of diagnostic quality (score ≥ 2/4) with very good interobserver agreement (AC1 = 0.91). Interobserver agreement for venous occlusion was also very good (AC1 = 0.93). The overall accuracy of FE-CMRV compared to catheter venography was perfect (100.0%). No additional imaging was required prior to a clinical management decision in any of the 52 patients. Twenty-four successful and uncomplicated venous interventions were carried out following pre-procedural vascular mapping with FE-CMRV.

CONCLUSIONS

3D FE-CMRV is a practical, accurate and robust technique for high-resolution mapping of central thoracic, abdominal and pelvic veins and can be used to inform image-guided therapy. It may play a pivotal role in the care of patients in whom conventional contrast agents may be contraindicated or ineffective.

Non-contrast three-dimensional gradient recalled echo Dixon-based magnetic resonance angiography/venography in children

Magnetic resonance imaging (MRI) has been considered a valuable diagnostic tool for noninvasive imaging of the vasculature in children and adults for more than two decades. While a variety of non-contrast MRI methods have been described for imaging of both arteries and veins (e.g., time-of-flight, phase contrast, and balanced steady-state free precession imaging), contrast-enhanced magnetic resonance angiography/venography are the most commonly employed vascular imaging techniques due to their high spatial and contrast resolutions and general reliability. In this technical innovation article, we describe a novel 3-D respiratory-triggered gradient recalled echo Dixon-based MR angiography/MR venography technique that provides high-resolution anatomical imaging of the vasculature of the neck, body and extremities without the need for intravenous contrast material or breath-holding.

Magnetic resonance angiography imaging of pulmonary embolism using agents with blood pool properties as an alternative to computed tomography to avoid radiation exposure

PURPOSE

To evaluate the feasibility and accuracy of a combined magnetic resonance angiography (MRA) - magnetic resonance venography (MRV) protocol using contrast agents with blood pool properties, gadofosveset trisodium and gadobenate dimeglumine, in the evaluation of pulmonary embolus (PE) and deep venous thrombosis (DVT) as compared to the standard clinical reference imaging modalities; computed tomography pulmonary angiography (CTPA) and color-coded Duplex ultrasound (DUS).

MATERIALS AND METHODS

This prospective clinical study recruited patients presenting to the emergency department with clinical suspicion for PE and scheduled for a clinically indicated CTPA. We performed both MRA of the chest for the evaluation of PE as well as MRV of the pelvis and thighs to evaluate for DVT using a single contrast injection. MRA-MRV data was compared to the clinical reference standard CTPA and DUS, respectively.

RESULTS

A total of 40 patients were recruited. The results on a per-patient basis comparing MRA to CTPA for pulmonary embolus yielded 100% sensitivity and 97% specificity. There was a small subset of patients that underwent clinical DUS to evaluate for DVT, which demonstrated a sensitivity and specificity of 100% for MRV.

CONCLUSIONS

This single-center, preliminary study using contrast agents with blood pool properties to perform a relatively rapid combined MRA-MRV exam to image for PE and above knee DVT shows potential as an alternative imaging choice to CTPA. Further large-scale, multicentre studies are warranted.

Contrast enhanced magnetic resonance venography in the follow-up evaluation of idiopathic intracranial hypertension patients with cerebral venous sinus stenting

PURPOSE

Role of contrast-enhanced magnetic resonance venography (CE-MRV) in the follow-up of venous sinus stenting (VSS) among the idiopathic intracranial hypertension (IIH) patients.

MATERIALS AND METHODS

Prospective evaluation of VSS patients with CE-MRV, DRCV and DSA for follow-up of clinically suspected recurrent stenosis. CE-MRV was evaluated against DRCV and DSA.

RESULTS

Ten patients with twelve episodes of recurrent symptoms. Sensitivity, specificity, PPV, NPV and accuracy of the CE-MRV for the detection of recurrent stenosis were: 100%, 33.33%, 81.82%, 100% and 83.3% respectively.

CONCLUSION

CE-MRV was a reliable first-line investigation for the detection of recurrent stenosis following VSS.

Clinical Presentation, Neuroimaging Findings, and Predictors of Brain Parenchymal Lesions in Cerebral Vein and Dural Sinus Thrombosis: A Retrospective Study

Introduction:

Cerebral venous sinus thrombosis (CVST) is an unusual cause of stroke with potentially serious consequences. This study was designed to investigate the clinical and neuroimaging features in patients with CVST and to analyze the predictors of brain parenchymal lesions.

Materials and Methods:

A retrospective study of 181 patients with CVST was conducted in a tertiary care hospital.

Results:

Of 181 patients (age range 14–96 years, mean age: 34.64 ± 14.66 years), 121 were female (66.9%). Most of the patients were in their third decade of life. Headache (47.51%) was the most common clinical presentation followed by seizures (24.31%). Transverse sinus (TS) (77.9%) was the most common site of venous sinus thrombosis. Brain parenchymal lesions were present in 63%, and each patient had subarachnoid and intraventricular hemorrhage. Hemorrhagic venous infarct was the most common brain parenchymal lesion (37.57%). Frontal region (25.4%) was the most common site of brain parenchymal lesions followed by frontoparietal region (21.9%). Women were more likely to have brain parenchymal lesions (72.4%, P = 0.034). Headache was the most common clinical presentation in patients without brain parenchymal lesions while seizures with brain parenchymal lesions. Straight sinus thrombosis was more likely to be associated with brain parenchymal lesions (P = 0.009).

Conclusion:

CVST presents in young and more commonly in females. TS was the most common site of venous sinus thrombosis. Female gender, seizures, altered sensorium and focal neurological deficit at presentation, and straight sinus thrombosis were more likely associated with the presence of brain parenchymal lesions.

Upper extremity non-contrast magnetic resonance venography (MRV) compared to contrast enhanced MRV and ultrasound

PURPOSE

To assess feasibility, image quality and measured venous caliber of non-contrast MRV (NC-MRV) of central and upper extremity veins, compared to contrast-enhanced MRV (CE-MRV) and ultrasound (US) in healthy volunteers.

MATERIALS AND METHODS

10 subjects underwent NC-MRV and CE-MRV at 1.5 T, with comparison to US. Two radiologists evaluated MRI for image quality (IQ) and venous caliber.

RESULTS AND CONCLUSIONS

NC-MRV is feasible, with inferior IQ but comparable venous caliber measurements CE-MRV (mean 7.9±4.58 mm vs. 7.83±4.62, p=0.13). Slightly larger upper limb caliber measurements were derived for NC-MRV and CE-MRV compared to US (NC-MRV 5.2±1.8 mm, CE-MRV 4.9±1.6 mm, US 4.5±1.8 mm, both p<0.001).

Dangerous Headache: A Case of Dural Venous Sinus Thrombosis with Protein S Deficiency

Dural Venous Sinus Thrombosis (DVST) is a sporadic cause of headache. DVST is a recherché complication of maxillary sinus infection. Maxillary sinusitis infection may spread directly to orbit via lamina papyracea and it is expedited by the presence veins of breschet. The authors present a clinical case of dural sinus thrombosis with protein S deficiency and also describe an effective management approach for DVST.

Prevalence of Extracranial Venous Narrowing on Magnetic Resonance Venography Is Similar in People With Multiple Sclerosis, Their Siblings, and Unrelated Healthy Controls: A Blinded, Case-Control Study

PURPOSE

The study sought to assess and compare the prevalence of narrowing of the major extracranial veins in subjects with multiple sclerosis and controls, and to assess the sensitivity and specificity of magnetic resonance venography (MRV) for describing extracranial venous narrowing as it applies to the chronic cerebrospinal venous insufficiency theory, using catheter venography (CV) as the gold standard.

METHODS

The jugular and azygos veins were assessed with time-of-flight MRV in this assessor-blinded, case-control study of subjects with multiple sclerosis, their unaffected siblings, and unrelated controls. The veins were evaluated by diameter and area, and compared with CV. Collateral vessels were also analyzed for maximal diameter, as a potential indicator of compensatory flow.

RESULTS

A high prevalence of extracranial venous narrowing was demonstrated in all study groups, collectively up to 84% by diameter criteria and 90% by area, with no significant difference between the groups when assessed independently (P = .34 and .63, respectively). There was high interobserver variability in the reporting of vessel narrowing (kappa = 0.32), and poor vessel per vessel correlation between narrowing on MRV and CV (kappa = 0.064). Collateral neck veins demonstrated no convincing difference in maximum size or correlation with jugular narrowing.

CONCLUSION

There is a high prevalence of narrowing of the major extracranial veins on MRV in all 3 study groups, with no significant difference between them. These findings do not support the chronic cerebrospinal venous insufficiency theory. Although MRV has shown a high sensitivity for identifying venous narrowing, time-of-flight imaging demonstrates poor interobserver agreement and poor specificity when compared with the gold standard CV.

Contrast-enhanced magnetic resonance venography in pediatric patients with chronic kidney disease: initial experience with ferumoxytol

Ferumoxytol is an ultra-small superparamagnetic iron oxide (USPIO) particle that is FDA-approved for parenteral treatment of iron deficiency anemia in adults with chronic kidney disease. Because of the association between gadolinium-based contrast agents and nephrogenic systemic fibrosis in patients with severe chronic kidney disease, we sought to evaluate the diagnostic role of ferumoxytol-enhanced MR venography in children with chronic kidney disease. Twenty children underwent 22 high-resolution ferumoxytol-enhanced MR venography examinations at 3.0 T. High-resolution 3-D contrast-enhanced imaging was performed at a minimum of 3 time points following injection of ferumoxytol at a total dose of 4 mg/kg. Two blinded pediatric radiologists independently scored six named veins on ferumoxytol-enhanced MR venography examinations according to a three-point subjective score, where a score ≥2 was considered diagnostic. Additionally, all relevant venous structures in the included field of view were analyzed for occlusive or non-occlusive thrombosis, compression and presence of collaterals. All patients underwent ferumoxytol-enhanced MR venography successfully and without adverse event. The overall scores of the reviewing radiologists for all venous structures were 2.7-2.9. In all cases, the reviewers were confident basing their diagnoses on the ferumoxytol-enhanced MR venography findings. In 12 of 22 examinations, findings on follow-up imaging or invasive procedures were available to correlate with the findings on ferumoxytol-enhanced MR venography. There was complete concordance between the findings from follow-up imaging and invasive procedures with findings from ferumoxytol-enhanced MR venography. Ferumoxytol holds promise as a powerful alternative to gadolinium-based contrast agents for reliable, high-resolution MR venography in children with chronic kidney disease.

Malignant isolated cortical vein thrombosis with type II protein S deficiency: a case report

Background

The incidence of cerebral venous thrombosis (CVT) is low, and in particular, isolated cortical vein thrombosis (ICVT) is very rare. The diagnosis of ICVT is difficult by using conventional computed tomography (CT) and magnetic resonance imaging (MRI). However, with appropriate treatment, ICVT has a good prognosis.

Case presentation

Herein, we present a rare case of a 40-year-old woman with ICVT and type II protein S (PS) deficiency, who experienced a stroke. She initially presented with generalized convulsions. A CT scan showed intracerebral hemorrhage (ICH) in the left temporoparietal region. However, her condition rapidly deteriorated and she went into a coma approximately 20 h after admission. A second CT scan revealed significant ICH expansion and transfalcine herniation. Decompressive hemicraniectomy with duraplasty was performed, and ICVT was confirmed owing to abnormal vascular tone and black appearance of the cortical vein. She underwent anticoagulation therapy and rehabilitation, and gradually recovered.

Conclusion

We experienced an extremely rare case of isolated cortical vein thrombosis related with type II PS deficiency. CT-digital subtraction angiography is a useful supportive technique in the diagnosis of ICVT. Decompressive hemicraniectomy is effective for hemorrhage extension cases, and ICVT with hemorrhage might require early anticoagulation therapy.

Compression of the posterior fossa venous sinuses by epidural hemorrhage simulating venous sinus thrombosis: CT and MR findings

BACKGROUND

Posterior fossa dural venous sinus thrombus is a well-described complication of head trauma, especially when fracture crosses the dural sinus grooves or in association with epidural hemorrhage. We have found that post-traumatic posterior fossa epidural hematoma compressing a dural venous sinus can mimic dural venous thrombus.

OBJECTIVE

To discuss the CT and MRI findings of posterior fossa epidural hemorrhages simulating sinus thrombosis, to make radiologists aware of this important imaging pitfall.

MATERIALS AND METHODS

We describe radiologic findings in four children in whom a posterior fossa epidural hemorrhage mimicked dural venous sinus thrombus. Routine CT head and CT venography were obtained on Toshiba volume and helical CT scanners. MRI and MR venography were performed on a Philips scanner.

RESULTS

In all cases there was medial displacement and compression of the posterior fossa dural venous sinuses without intraluminal thrombosis. The epidural hemorrhage was seen tracking along sinus grooves in the occipital bone, peeling the dura containing the sinuses from the calvarium and compressing the sinus, simulating thrombosis on axial CT views.

CONCLUSION

Both venous sinus thrombosis and posterior fossa epidural hemorrhages in children are well-described complications of head trauma. Posterior fossa epidural hemorrhage can mimic a sinus thrombus by compressing and displacing the sinuses. It is important to recognize this pitfall because treatment of a suspected thrombus with anticoagulation can worsen epidural hemorrhage.

Venous injury in abusive head trauma

BACKGROUND

Abusive head trauma (AHT) is an important cause of serious brain injury in infants and young children who have characteristic clinical and imaging findings that are discordant with the clinical history provided. Recent attention has focused on abnormalities of the cranial venous sinuses and cortical veins, both on MRI and at autopsy. Although many have interpreted these to be secondary to the AHT, some have recently argued that these venous abnormalities represent primary cortical sinus and venous thrombosis that leads secondarily to subdural hemorrhage and secondary brain injury. Direct trauma to the veins and sinuses has been reported at autopsy in AHT, but there has been no systematic study of venous abnormalities in cases of AHT.

OBJECTIVE

The purpose of this study was to define the incidence and characteristics of venous and sinus abnormalities in AHT.

MATERIALS AND METHODS

We included all children <36 months of age who were diagnosed with abusive head trauma between 2001 and 2012 and who had MRI and magnetic resonance (MR) venography as part of their diagnostic workup. We analyzed age, gender and clinical findings. MRI and MR venography were analyzed independently by two neuroradiologists with a focus on abnormalities involving the intracranial veins and venous sinuses.

RESULTS

A total of 45 children were included. The median age was 3 months (range 15 days to 31 months) and 28 were boys (62%). Clinical findings included retinal hemorrhage in 71% and extracranial fractures in 55%. CT or MRI demonstrated subdural hemorrhage in 41 (91%); none had subdural effusions. In 31 cases (69%) MR venography demonstrated mass effect on the venous sinuses or cortical draining veins, with either displacement or partial or complete effacement of the venous structures from an adjacent subdural hematoma or brain swelling. We also describe the lollipop sign, which represents direct trauma to the cortical bridging veins and was present in 20/45 (44%) children.

CONCLUSION

Evidence of displacement or compression of cortical veins and sinuses from subdural hemorrhage or edema on MR venography was present in the majority of children with abusive head trauma. Evidence of direct trauma to the veins (lollipop sign) was identified in nearly half of cases. It is important to understand the superimposed effects of subdural hematoma and brain swelling on the veins and sinuses to differentiate it from cortical sinus and venous thrombosis.

Splenic artery aneurysm as an unusual cause of new onset ascites: a case report

Splenic artery aneurysm (SAA) is a rare and potentially life-threatening clinical entity that carries a risk of rupture and peritoneal hemorrhage. When ruptured, it typically manifests as abdominal pain with hemodynamic instability. This is a report about a 29-year-old male admitted for evaluation of recentonset ascites following the spontaneous resolution of a transient episode of severe epigastric and left upper quadrant pain with syncope the preceding day. Paracentesis revealed bloody fluid. Abdominal computed tomographic angiography (CTA) and magnetic resonance venography (MRV) showed a three centimeter SAA. During admission, prompt exploratory laparotomy was performed that revealed excessive intraperitoneal hemorrhage due to a ruptured SAA. The pathology report confirmed that the SAA had developed secondaryto atherosclerosis. Careful history taking together with appropriate imaging tests and emergent surgical intervention led to a timely diagnosis and the patient' ssurvival.

Port-a-cath-related thrombosis and postthrombotic syndrome in pediatric oncology patients

OBJECTIVE

To investigate Port-A-Cath (PAC)-related thrombosis and postthrombotic syndrome (PTS) in children with cancer.

STUDY DESIGN

The study population was a consecutive cohort of children diagnosed with cancer and a PAC implanted at diagnosis. Children were evaluated for the presence of PAC-related thrombosis by magnetic resonance venography and the presence of congenital prothrombotic risk factors and PTS.

RESULTS

A total of 114 children (median age, 6.04 years) were included. Of these children, 48 (42%) were treated for solid tumors and 66 (58%) were treated for hematopoietic tumors, including 38 for acute lymphoblastic leukemia. At the time of magnetic resonance venography, 42 children (37%) had the PAC still in place, and 72 (63%) had the PAC removed. Overall, PACs were in place for a total of 324.92 PAC-years. PAC-related thrombosis was detected in 45 children (39.5%) with a current or previous PAC. Of these, 21 (47%) had a solid tumor, 14 (31%) had acute lymphoblastic leukemia, and 10 (22%) had another hematopoietic tumor. Younger age at diagnosis, female sex, duration of PAC use, and left-side PAC placement were independently associated with an increased risk of thrombosis, whereas asparaginase therapy and the presence of inherited prothrombotic risk factors were not. Mild PTS (ie, presence of prominent collateral vessels in the skin) was present in 5.6% of the children.

CONCLUSION

PAC-related thrombosis is common in pediatric oncology patients. In some children, thrombotic complications can lead to the development of PTS.

Magnetic resonance venography and liver transplant complications

Hepatic vein stenosis is a rare but serious complication following liver transplantation. Multiple modalities can be utilized to image the hepatic vasculature. Magnetic resonance venography (MRV) provides certain advantages over ultrasound, computed tomography angiography and digital subtraction venography. MRV utilizes the same imaging principles of magnetic resonance angiography in order to image the venous system. Blood pool contrast agents, specifically gadofosveset trisodium, allow for steady state imaging up to 1 h following injection, with improved visualisation of vital venous structures by utilising delayed steady state imaging. Additionally, the inherent physics properties of magnetic resonance imaging also provide excellent soft tissue detail and thus help define the extent of complications that often plague the post-liver transplant patient. This case report describes the use of gadofosveset trisodium in a patient with hepatic venous stenosis following liver transplantation. Initial venography failed to outline the stenoses and thus MRV using a blood pool contrast agent was utilised in order to delineate the anatomy and plan a therapeutic endovascular procedure.

Does bilateral transverse cerebral venous sinus stenosis exist in patients without increased intracranial pressure?

OBJECTIVE

Transverse cerebral venous sinus stenosis (TSS) is common among patients with idiopathic intracranial hypertension. TSS likely also exists among individuals with normal intracranial pressure (ICP) but the prevalence is unclear. The goal of this study was to identify patients with incidental TSS and normal ICP and describe their characteristics.

METHODS

Among 240 adult patients who underwent brain magnetic resonance imaging (MRI) with magnetic resonance venography (MRV) with contrast at our institution between September 2009 and September 2011, 44 had isolated TSS without further substantial imaging abnormality. Medical records were reviewed for symptoms of increased ICP, papilledema, cerebrospinal fluid (CSF) constituents and opening pressure (OP), and reason for brain imaging. Of these, 37 were excluded for confirmed or possible idiopathic intracranial hypertension. Of the remainder, 5 had CSF-OP≤25 cmH2O without papilledema, and 2 did not have measured ICP, but had no papilledema or symptoms of increased ICP. Imaging was re-interpreted to assess for signs suggestive of elevated ICP and to characterize the TSS further.

RESULTS

All patients were women (mean age: 41, mean BMI: 37.1). CSF contents were normal, but OPs were at the upper limit of normal (22-25 cmH2O). Indications for MRI/MRV included query pituitary abnormality (1), migraine (4), and anomalous-appearing optic nerves (2). All had bilateral TSS. Six had short TSS and an empty sella; 1 had long TSS and no empty sella; 1 had flattening of the posterior sclera; 2 had prominence of peri-optic nerve CSF.

CONCLUSION

Asymptomatic bilateral TSS exists in patients with ICP≤25 cmH2O, but is likely uncommon. CSF-OP was at the upper limit of normal in our patients, who also had other radiologic signs suggestive (but not specific) of chronically-raised ICP. Findings of bilateral TSS on imaging should prompt funduscopic examination for papilledema.