Alterations in brain activation patterns in women with functional defecatory disorder: A novel fMRI rectal balloon expulsion study.

BACKGROUND: Functional defecatory disorders (FDD) are common among women. Despite the extensive research on peripheral mechanisms involved in FDD, the central-neural contribution to its pathophysiology remains poorly understood. We aimed to delineate specific supra-spinal regions involved in defecation and examine whether their activity, as measured by blood-oxygen-level-dependent (BOLD) signals, is different in FDD. METHODS: We performed functional MRI (fMRI) with concurrent rectal manometry in 15 controls and 18 females with ROME III diagnosis of FDD. A block design was used and brain activation maps based on BOLD effect employing the generalized linear model were calculated for each subject. Statistical significance between groups was assessed by a Student t-test with cluster-based multiple comparisons correction (corrected p < 0.01). KEY RESULTS: Simulated defecation was associated with activation of regions of primary and supplementary motor (SMA) and somatosensory cortices, homeostatic afferent (thalamus, mid-cingulate cortex, and insula), and emotional arousal networks (hippocampus and prefrontal cortex), occipital and cerebellum along with deactivation of right anterior cingulate cortex (ACC) in controls. Women with FDD had fewer regions engaged in defecation and BOLD activation was much decreased is areas related to executive-cognitive function (insula, parietal, and prefrontal cortices). Patients unlike controls showed activation in right ACC and otherwise had similar brain activation patterns during anal squeeze. CONCLUSIONS & INFERENCES: Our results provide evidence that distinct differences exist in supra-spinal control of defecation in key regions of motivational-affective regulation and executive-cognitive function, in patients with FDD as compared to controls.

Similarity of individual functional brain connectivity patterns formed by music listening quantified with a data-driven approach.

INTRODUCTION: This study aims to explore the similarities in functional connectivity (FC) patterns in individuals when listening to different music genres and, in comparison, to the spoken word, using a novel data-driven approach. Our model and findings can potentially be utilized for evaluating the neurological effects of therapeutic music interventions. MATERIALS AND METHODS: Twelve healthy volunteers listened to seven different sound tracks while undergoing functional magnetic resonance imaging (fMRI) scans: music of the volunteer's choice with positive emotional attachment, two selections of unfamiliar classical music, one classical piece repeated with visual guidance and three spoken language tracks. FC network graphs were created, and selected graph properties were evaluated toward their commonalities across sound tracks. For comparison, FC patterns represented by the graph adjacency matrices were directly compared for high and low BOLD activation during listening. RESULTS: Graph properties averaged across subjects showed similar values for the same sound track compared to different sound tracks (p < 0.003). For high BOLD activation involving most areas in the auditory cortex, FC patterns for the same sound track correlated highly (0.74 ± 0.11), whereas FC patterns for different sound tracks did not (0.09 ± 0.07; p < 6e-5). For low BOLD activation involving additional brain regions, correlation of FC patterns for the sound tracks was still higher (0.43 ± 0.07) than for different sound tracks (0.09 ± 0.05; p < 8e-6). CONCLUSION: Similar music creates similar functional activation and connectivity patterns in the brain of healthy individuals as does listening to the spoken word. Direct comparison of FC patterns yielded higher correlations than indirect comparisons of graph properties derived from corresponding FC networks.

An Exploratory Pilot Study of Brain Activation and Functional Connectivity Induced by the "Goldberg" Variations 276 years after their Commission.

Around 1741, composer Johann Sebastian Bach published a long and complicated keyboard piece, calling it Aria with diverse variations for a harpsichord with two manuals. It was the capstone of a publication project called German Clavier-Übung (Keyboard Practice) where Bach wanted to show what was possible at the keyboard in terms of technical development, virtuosic finesse and compositional sophistication. The music is meticulously patterned, beginning with a highly ornamented Aria, the bass line of which fuels the 30 variations that follow. The piece is clearly divided into two parts with the second half beginning with an overture with a fanfare opening, in variation 16. The piece ends as it begins, with the return of the Aria. Here, we present an investigation into activation and connectivity in the brain of a pianist, who listened to her own recording of the "Goldberg" variation while undergoing a fMRI examination. Similarity of brain connectivity is quantified and compared with the subjective scores provided by the subject.

Application of three-dimensional printing for pre-operative planning in hip preservation surgery.

Three-dimensional printing is a valuable modality with broad clinical applications. Hip preservation surgery outcomes are dependent on correction of morphological abnormalities that may be optimally visualized with three-dimensional models. To assess the efficacy of three-dimensional models for patient and trainee education and to determine its benefits during pre-operative planning in hip preservation surgery. Sixteen patients with hip pathology were selected. Computed tomography was utilized to generate three-dimensional models. Customized Likert-style questionnaires were given to 10 hip preservation surgeons, 11 orthopedic surgery residents and 10 patients. All residents strongly agreed or agreed that the three-dimensional hip models helped them to understand patients' pathology. All but one patient agreed that the models assisted in their understanding of the treatment plan. Surgeons concurred that although they do not routinely order three-dimensional models, their use would improve trainee and patient education, especially when treating atypical osseous pathomorphologies. Three-dimensional models are tools that can help surgeon, trainee and patient understanding and participation in treatment of complex hip disorders. Patients and trainees agree that the prototypes enhanced their educational experience, as the surgeon can directly demonstrate complex morphological abnormalities. Trainees can therefore gain a better understanding of hip pathologies and treatment. As patients better understand their hip disorder, they can more fully participate in shared treatment decision-making. LEVEL OF EVIDENCE: Level IV, Retrospective Case Series.

MRI-based methodology to monitor the impact of positional changes on the airway caliber in obstructive sleep apnea patients.

PURPOSE: To develop a non-invasive MRI-based methodology to visually and quantitatively assess the impact of head and chest rotations on the airway caliber. METHODS: An MRI table set-up was developed for independent rotations of the head and chest along B0 field and tested for feasibility using phantom scans. The accuracy of the head and chest rotations was validated with ten volunteer scans. A 3T MRI protocol was optimized to image the regions of interest (ROIs) that were the retropalatal (RP) and retroglossal (RG) sections of the upper airway. A workflow for data analysis was developed to assess the changes of the airway caliber following the independent head and chest rotations. RESULTS: A prototype MRI table setup was established with two separate plates each supporting and rotating the head or chest independently. Subject positioning and image acquisition were finished within seven minutes for each position. Thus, each subject MRI was set up with seven positions and completed for less than one hour. The implemented angles were within 0.3-degree deviation from the targeted angles. The data analysis workflow provided 2D and 3D visualization and quantification with the measurements of cross-sectional area, lateral and anterior-posterior distances of the ROIs. Sharp contrast of the airway and its surrounding tissues facilitated an automatic approach to ROI placement to minimize subjectivity. CONCLUSIONS: The 3T MRI data acquisition and analysis methodology could reliably assess the impact of head and chest rotations on the upper airway caliber to identify the optimal position for obstructive sleep apnea patients.

Multiple Aneurysms AnaTomy CHallenge 2018 (MATCH)-phase II: rupture risk assessment.

PURPOSE: Assessing the rupture probability of intracranial aneurysms (IAs) remains challenging. Therefore, hemodynamic simulations are increasingly applied toward supporting physicians during treatment planning. However, due to several assumptions, the clinical acceptance of these methods remains limited. METHODS: To provide an overview of state-of-the-art blood flow simulation capabilities, the Multiple Aneurysms AnaTomy CHallenge 2018 (MATCH) was conducted. Seventeen research groups from all over the world performed segmentations and hemodynamic simulations to identify the ruptured aneurysm in a patient harboring five IAs. Although simulation setups revealed good similarity, clear differences exist with respect to the analysis of aneurysm shape and blood flow results. Most groups (12/71%) included morphological and hemodynamic parameters in their analysis, with aspect ratio and wall shear stress as the most popular candidates, respectively. RESULTS: The majority of groups (7/41%) selected the largest aneurysm as being the ruptured one. Four (24%) of the participating groups were able to correctly select the ruptured aneurysm, while three groups (18%) ranked the ruptured aneurysm as the second most probable. Successful selections were based on the integration of clinically relevant information such as the aneurysm site, as well as advanced rupture probability models considering multiple parameters. Additionally, flow characteristics such as the quantification of inflow jets and the identification of multiple vortices led to correct predictions. CONCLUSIONS: MATCH compares state-of-the-art image-based blood flow simulation approaches to assess the rupture risk of IAs. Furthermore, this challenge highlights the importance of multivariate analyses by combining clinically relevant metadata with advanced morphological and hemodynamic quantification.

Similarity of functional connectivity patterns in patients with multiple sclerosis who void spontaneously versus patients with voiding dysfunction.

AIM: To investigate if Multiple Sclerosis (MS) lesion characteristics affect functional brain connectivity (FC) during bladder voiding. METHODS: Twenty-seven ambulatory female patients with MS completed our functional magnetic resonance imaging (fMRI)/urodynamic testing (UDS) platform. Individual fMRI activation maps were generated at initiation of voiding. FC patterns of these regions were calculated and compared. Similarity of the FC pattern from one patient relative to all others was expressed by a parameter FC_sim. A statistical analysis was performed to reveal the relationship of the existence of an enhancing brain lesion, the size of the largest lesion and the ability to void spontaneously to this FC similarity measure. RESULTS: FC_sim values were significantly lower for patients with an enhancing MS lesion (11.7 ± 3.1 vs 5.3 ± 2.1 P < 0.001). Lesion size smaller than 20 mm inversely correlated significantly with FC_sim (R = -0.43, P = 0.05). Patients with the ability to void spontaneously had a higher FC_sim value (12.0 ± 2.8 vs 9.3 ± 4.4 s, P = 0.08). Patients that exhibited a decrease of compliance also showed a significantly lower FC_sim value (11.3 ± 3.5 vs 4.7 ± 0.7, P < 1e-5). CONCLUSION: FC connectivity analysis derived from an fMRI task-based study including repetitive voiding cycles is able to quantify the heterogeneity of connectivity patterns in the brain of MS patients. FC similarity decreased with maximum lesion size or the presence of enhancing lesions affecting the ability to void spontaneously.

Higher Neural Correlates in Patients with Multiple Sclerosis and Neurogenic Overactive Bladder Following Treatment with Intradetrusor Injection of OnabotulinumtoxinA.

PURPOSE: OnabotulinumtoxinA is a well described treatment of neurogenic overactive bladder. While motor effects on the detrusor muscle have been extensively studied, the sensory effects have not. The aim of this study was to evaluate the impact of intradetrusor onabotulinumtoxinA injection on brain activity in female patients with multiple sclerosis and neurogenic overactive bladder. MATERIALS AND METHODS: We prospectively studied 12 women with stable multiple sclerosis and neurogenic overactive bladder using concurrent functional magnetic resonance imaging and urodynamic studies prior to and 6 to 10 weeks following onabotulinumtoxinA injection. Individual functional magnetic resonance imaging activation maps at the time of strong urgency were averaged before and after onabotulinumtoxinA injection where areas of significant activation were identified. RESULTS: After onabotulinumtoxinA injection functional magnetic resonance imaging activation increased in the right cingulate body (p = 0.0012), the left posterior cingulate (p = 0.02), the left anterior cingulate (p = 0.0015), the right prefrontal cortex (p = 0.0015), the insula (p = 0.0138) and the pons micturition center (p = 0.05). Sparse areas showed decreased activity, including the left cerebellum (p = 0.001), the left fusiform gyrus (p = 0.065) and the bilateral lentiform nucleus (p = 0.026). CONCLUSIONS: Intradetrusor injection of onabotulinumtoxinA appeared to increase the activity of most brain regions known to be involved in the sensation and process of urinary urgency in female patients with multiple sclerosis and neurogenic overactive bladder. To our knowledge this is the first study of its kind to evaluate the possible effects of onabotulinumtoxinA at the human brain level where sensory awareness is located. This activation pattern may be used to further phenotype patients to optimize therapy or determine the sensory effects of onabotulinumtoxinA beyond the bladder.

Multiple Aneurysms AnaTomy CHallenge 2018 (MATCH): Phase I: Segmentation.

PURPOSE: Advanced morphology analysis and image-based hemodynamic simulations are increasingly used to assess the rupture risk of intracranial aneurysms (IAs). However, the accuracy of those results strongly depends on the quality of the vessel wall segmentation. METHODS: To evaluate state-of-the-art segmentation approaches, the Multiple Aneurysms AnaTomy CHallenge (MATCH) was announced. Participants carried out segmentation in three anonymized 3D DSA datasets (left and right anterior, posterior circulation) of a patient harboring five IAs. Qualitative and quantitative inter-group comparisons were carried out with respect to aneurysm volumes and ostia. Further, over- and undersegmentation were evaluated based on highly resolved 2D images. Finally, clinically relevant morphological parameters were calculated. RESULTS: Based on the contributions of 26 participating groups, the findings reveal that no consensus regarding segmentation software or underlying algorithms exists. Qualitative similarity of the aneurysm representations was obtained. However, inter-group differences occurred regarding the luminal surface quality, number of vessel branches considered, aneurysm volumes (up to 20%) and ostium surface areas (up to 30%). Further, a systematic oversegmentation of the 3D surfaces was observed with a difference of approximately 10% to the highly resolved 2D reference image. Particularly, the neck of the ruptured aneurysm was overrepresented by all groups except for one. Finally, morphology parameters (e.g., undulation and non-sphericity) varied up to 25%. CONCLUSIONS: MATCH provides an overview of segmentation methodologies for IAs and highlights the variability of surface reconstruction. Further, the study emphasizes the need for careful processing of initial segmentation results for a realistic assessment of clinically relevant morphological parameters.

Augmented Reality with Virtual Cerebral Aneurysms: A Feasibility Study.

OBJECTIVE: Advanced magnetic resonance imaging (MRI) acquisition methods such as 4D phase contrast magnetic resonance imaging (4D pcMRI) have found widespread applications in assessing hemodynamics in cerebral aneurysms. One of the goals is the identification of a hemodynamic scenario predictive of aneurysm rupture. Because of the technical complexity the 4D pcMRI technology, challenges exist in extracting and communicating the wealth of information contained in the MRI image data, in particular, to a multidisciplinary team of health professionals and basic scientists. METHODS: Here we introduce a new resource in the form of a commercially available optical see-through head-mounted display, which allows augmenting the real world by computer-generated virtual objects. RESULTS: An image processing algorithm was presented for integrating 3D surface models derived from 3D rotational angiography data, 3D time-of-flight MRI data, and 4D pcMRI data into the augmented reality environment. This new approach was successfully evaluated on blood flow data acquired before and after flow diverter treatment in 6 patients harboring a cerebral aneurysm. CONCLUSIONS: Augmented reality may become an additional means for visualizing complex medical data, in particular complex flows as illustrated here.

Tumor radiomic heterogeneity: Multiparametric functional imaging to characterize variability and predict response following cervical cancer radiation therapy.

BACKGROUND: Robust approaches to quantify tumor heterogeneity are needed to provide early decision support for precise individualized therapy. PURPOSE: To conduct a technical exploration of longitudinal changes in tumor heterogeneity patterns on dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI) and FDG positron emission tomography / computed tomography (PET/CT), and their association to radiation therapy (RT) response in cervical cancer. STUDY TYPE: Prospective observational study with longitudinal MRI and PET/CT pre-RT, early-RT (2 weeks), and mid-RT (5 weeks). POPULATION: Twenty-one FIGO IB2 -IVA cervical cancer patients receiving definitive external beam RT and brachytherapy. FIELD STRENGTH/SEQUENCE: 1.5T, precontrast axial T1 -weighted, axial and sagittal T2 -weighted, sagittal DWI (multi-b values), sagittal DCE MRI (<10 sec temporal resolution), postcontrast axial T1 -weighted. ASSESSMENT: Response assessment 1 month after completion of treatment by a board-certified radiation oncologist from manually delineated tumor volume changes. STATISTICAL TESTS: Intensity histogram (IH) quantiles (DCE SI10% and DWI ADC10% , FDG-PET SUVmax ) and distribution moments (mean, variance, skewness, kurtosis) were extracted. Differences in IH features between timepoints and modalities were evaluated by Skillings-Mack tests with Holm's correction. Area under receiver-operating characteristic curve (AUC) and Mann-Whitney testing was performed to discriminate treatment response using IH features. RESULTS: Tumor IH means and quantiles varied significantly during RT (SUVmean : ↓28-47%, SUVmax : ↓30-59%, SImean : ↑8-30%, SI10% : ↑8-19%, ADCmean : ↑16%, P < 0.02 for each). Among IH heterogeneity features, FDG-PET SUVCoV (↓16-30%, P = 0.011) and DW-MRI ADCskewness decreased (P = 0.001). FDG-PET SUVCoV was higher than DCE-MRI SICoV and DW-MRI ADCCoV at baseline (P < 0.001) and 2 weeks (P = 0.010). FDG-PET SUVkurtosis was lower than DCE-MRI SIkurtosis and DW-MRI ADCkurtosis at baseline (P = 0.001). Some IH features appeared to associate with favorable tumor response, including large early RT changes in DW-MRI ADCskewness (AUC = 0.86). DATA CONCLUSION: Preliminary findings show tumor heterogeneity was variable between patients, modalities, and timepoints. Radiomic assessment of changing tumor heterogeneity has the potential to personalize treatment and power outcome prediction. LEVEL OF EVIDENCE: 2 Technical Efficacy: Stage 3 J. Magn. Reson. Imaging 2018;47:1388-1396.

Four-Dimensional Phase Contrast Magnetic Resonance Imaging Protocol Optimization Using Patient-Specific 3-Dimensional Printed Replicas for In Vivo Imaging Before and After Flow Diverter Placement.

OBJECTIVE: Hemodynamics in cerebral aneurysms are currently investigated toward clinical efficacy using nonstandardized computational simulation techniques. At the same time, flow patterns and velocities are accessible by 4-dimensional phase contrast magnetic resonance imaging (4D pcMRI). Complexity of protocol design and imaging duration has limited the use of this technique in clinical imaging. A new approach is presented to overcome these limitations. METHODS: Three-dimensional (3D) replicas of 2 cerebral aneurysms were fabricated by fused deposition prototyping (3D printing) and imaged using 4D pcMRI while connected to a magnetic resonance imaging-compatible continuous flow loop. Acquisition parameters were optimized with imaging times not to exceed 10 minutes. Six patients harboring cerebral aneurysms with sizes ranging from 4.7 to 13.8 mm were imaged with the optimized 4D pcMRI protocol. After treatment with the pipeline embolization device (PED), 4D pcMRI examinations were repeated in 3 patients. RESULTS: In all cases, major flow patterns were visualized well; smaller aneurysms posed a challenge because of limited spatial resolution, whereas larger aneurysms contained regions of low velocity resulting in limited contrast in the flow-sensitive images. After PED placement, ordered aneurysmal flow was disrupted and intra-aneurysmal velocity was reduced on average by 24.5% (range, 12.9-31.5%). Exploratory statistical analysis yielded a positive significant correlation (P < 0.01) between changes in inflow velocity and posttreatment intra-aneurysmal flow velocity. CONCLUSIONS: 4D pcMRI flow imaging in cerebral aneurysms within a time frame suitable for clinical imaging applications is feasible with optimized acquisition parameters, thereby enabling quantification of intra-aneurysmal flow changes after flow diverter device treatment.

Effect of parallel radiofrequency transmission on arterial input function selection in dynamic contrast-enhanced 3 Tesla pelvic MRI.

BACKGROUND: To evaluate whether parallel radiofrequency transmission (mTX) can improve the symmetry of the left and right femoral arteries in dynamic contrast enhanced magnetic resonance imaging (DCE-MRI) of prostate and bladder cancer. METHODS: Eighteen prostate and 24 bladder cancer patients underwent 3.0 Tesla DCE-MRI scan with a single transmission channel coil. Subsequently, 21 prostate and 21 bladder cancer patients were scanned using the dual channel mTX upgrade. The precontrast signal ( S0) and the maximum enhancement ratio (MER) were measured in both the left and the right femoral arteries. Within the patient cohort, the ratio of S0 and MER in the left artery to that in the right artery ( S0_LR, MER_LR) was calculated with and without the use of mTX. Left to right asymmetry indices for S0 ( S0_LRasym) and MER ( MER_LRasym) were defined as the absolute values of the difference between S0_LR and 1, and the difference between MER_LR and 1, respectively. RESULTS: S0_LRasym, and MER_LRasym were 0.21 and 0.19 for prostate cancer patients with mTX, and 0.43 and 0.45 for the ones imaged without it (P < 0.001). Also, for the bladder cancer patients, S0_LRasym, and MER_LRasym were 0.11 and 0.9 with mTX, while imaging without it yielded 0.52 and 0.39 (P < 0.001). CONCLUSION: mTX can significantly improve left-to-right symmetry of femoral artery precontrast signal and contrast enhancement.

Performance comparison of 1.5-T endorectal coil MRI with 3.0-T nonendorectal coil MRI in patients with prostate cancer.

RATIONALE AND OBJECTIVES: To compare prostate morphology, image quality, and diagnostic performance of 1.5-T endorectal coil magnetic resonance (MR) imaging (MRI) and 3.0-T nonendorectal coil MRI in patients with prostate cancer. MATERIALS AND METHODS: MR images obtained of 83 patients with prostate cancer using 1.5-T MRI systems with an endorectal coil were compared to images collected from 83 patients with a 3.0-T MRI system. Prostate diameters were measured, and image quality was evaluated by one American Board of Radiology (ABR)-certified radiologist (reader 1) and one ABR-certified diagnostic medical physicist (reader 2). The likelihood of the presence of peripheral zone cancer in each sextant and local extent was rated and compared to histopathologic findings. RESULTS: Prostate anterior-posterior diameter measured by both readers was significantly shorter with 1.5-T endorectal MRI than with 3.0-T MRI. The overall image quality score difference was significant only for reader 1. Both readers found that the two MRI systems provided a similar diagnostic accuracy in cancer localization, extraprostatic extension, and seminal vesicle involvement. CONCLUSIONS: Nonendorectal coil 3.0-T MRI provides prostate images that are natural in shape and that have comparable image quality to those obtained at 1.5 T with an endorectal coil, but not superior diagnostic performance. These findings suggest an opportunity exists for improving technical aspects of the 3.0-T prostate MRI.

Magnetic resonance imaging signatures of vascular pathology in multiple sclerosis.

Venous vascular contributing factors to multiple sclerosis (MS) have been known for some time. Only recently has the scope of their potential role become more apparent with the theory of chronic cerebrospinal venous insufficiency (CCSVI). As research expands to further explore the role of vascular pathology in the MS population, it is expedient to review the evidence from an imaging perspective. In this paper, we review the current state-of-the-art methods using magnetic resonance imaging (MRI) as applied to imaging MS patients and CCSVI. This includes evaluating imaging signatures of vascular structure and flow as well as brain iron content. Upon review of the literature, we find that extracranial venous anomalies including stenosis, venous malformations, and collateralization of flow in the major veins of the neck have been observed to be prevalent in the MS population. Abnormal flow has been reported in MS patients both in major vessels using phase-contrast flow quantification and in the brain using perfusion-weighted imaging. We discuss the role of quantitative flow imaging and its potential in assessing possible biomarkers for abnormal flow. Finally, it has been suggested that the presence of high iron content may indirectly indicate progression of existing vascular pathology. To that end, we review the use of susceptibility-weighted imaging in monitoring iron in the thalamus, basal ganglia, and MS lesions.

Characteristics of flow through the internal jugular veins at cervical C2/C3 and C5/C6 levels for multiple sclerosis patients using MR phase contrast imaging.

OBJECTIVES: To study blood flow characteristics through the internal jugular veins (IJVs) at the cervical levels C2/C3 and C5/C6 in the neck of multiple sclerosis (MS) patients. METHODS: Magnetic resonance imaging at 3T was performed on 323 MS patients. Phase contrast imaging was used to quantify blood flow at both the C2/C3 and C5/C6 levels. Total IJV flow (tIJF) was normalized by total arterial flow (tAF). Contrast-enhanced time-resolved 3D MR arteriovenography and 2D time-of-flight MR venography were performed to assess IJV anatomy. Based on this assessment, the MS population was divided into non-stenotic (NST) and stenotic (ST) subjects. RESULTS: Of all the patients, 100 (31%) belonged to the NST group and 223 (69%) belonged to the ST group. At the C2/C3 and C5/C6 levels, the normalized tIJF of the ST group was 56±26% and 51±23%, respectively. This was significantly lower than that of the NST group, 85±13% and 73±12% (P<0·001). Zero percent and 5% of the NST group had a normalized tIJF of less than 50% at the C2/C3 and C5/C6 levels, compared to 37% and 47% for the ST group. The tAF was smaller for the secondary and primary progressive MS patients than the relapsing remitting MS patients (P = 0·02 and 0·01, respectively), while the tIJF was similar among all MS types. CONCLUSION: Total blood flow through the IJVs at both the C2/C3 and C5/C6 levels was reduced in the ST group compared to the NST group.

Using magnetic resonance imaging as a means to study chronic cerebral spinal venous insufficiency in multiple sclerosis patients.

The goal of this work is to present a broad magnetic resonance imaging (MRI) protocol for use in the study of chronic cerebrospinal venous insufficiency (CCSVI). The CCSVI MRI protocol includes the following sequences: time-resolved contrast-enhanced 3D MR angiography, 2D time-of-flight MR venography, and 3D volumetric interpolated breath-hold examination to assess venous structural abnormalities; phase-contrast MR imaging at different levels in the neck and thoracic cavity to quantify flow through the veins, arteries, and cerebrospinal fluid; T2-weighted imaging, T2-weighted fluid-attenuated inversion recovery, and pre- and post-contrast T1-weighted imaging of the brain for examinations of parenchymal lesions; and finally, susceptibility-weighted imaging for quantification of iron deposition in the brain. Data from 111 clinically definite multiple sclerosis patients were assessed for potential structural and flow CCSVI risk criteria, including stenosis, atresia, aplasia, dominant to subdominant venous flow ratio (D:sD), and the sum of their flow rates. Of the 111 patients, 50 (45%) were determined to be nonstenotic (NST) with no stenosis or atresia in their internal jugular veins (IJV), and the rest 61 (55%) were stenotic (ST) having at least one internal jugular vein stenosis or atresia. No occurrence of aplasia was observed. A D:sD of greater than 3:1 was observed in 15 (24.6%) patients of the ST group and 2 (4.0%) patients of the NST group. A sum of dominant and subdominant venous flow rate of <8 mL/s was observed in 22 (36.1%) patients of the ST group and 6 (12.0%) patients of the NST group. MRI provides valuable information in the observation of potential CCSVI risk factors. Low total flow in the 2 dominant veins seemed to be the strongest indicator for risk of having stenoses in the multiple sclerosis population.