Foundations of the Diagnosis and Management of Idiopathic Intracranial Hypertension and Pulsatile Tinnitus.

Venous sinus stenosis has garnered increasing academic attention as a potential etiology of idiopathic intracranial hypertension (IIH) and pulsatile tinnitus (PT). The complex anatomy of the cerebral venous sinuses and veins plays a crucial role in the pathophysiology of these conditions. Venous sinus stenosis, often found in the superior sagittal or transverse sinus, can lead to elevated intracranial pressure (ICP) and characteristic IIH symptoms. Stenosis, variations in dural venous anatomy, and flow dominance patterns contribute to aberrant flow and subsequent PT. Accurate imaging plays a vital role in diagnosis, and magnetic resonance (MR) venography is particularly useful for detecting stenosis. Management strategies for IIH and PT focus on treating the underlying disease, weight management, medical interventions, and, in severe cases, surgical or endovascular procedures. Recently, venous sinus stenting has gained interest as a minimally invasive treatment option for IIH and PT. Stenting addresses venous sinus stenosis, breaking the feedback loop between elevated ICP and stenosis, thus reducing ICP and promoting cerebrospinal fluid outflow. The correction and resolution of flow aberrances can also mitigate or resolve PT symptoms. While venous sinus stenting remains an emerging field, initial results are promising. Further research is needed to refine patient selection criteria and evaluate the long-term efficacy of stenting as compared to traditional treatments.

Challenges in the use of Venous Sinus Stenting in the Treatment of Idiopathic Intracranial Hypertension and Pulsatile Tinnitus.

Although numerous case series and meta-analyses have shown the efficacy of venous sinus stenting (VSS) in the treatment of idiopathic intracranial hypertension and idiopathic intracranial hypertension-associated pulsatile tinnitus, there remain numerous challenges to be resolved. There is no widespread agreement on candidacy; pressure gradient and failed medical treatment are common indications, but not all clinicians require medical refractoriness as a criterion. Venous manometry, venography, and cerebral angiography are essential tools for patient assessment, but again disagreements exist regarding the best, or most appropriate, diagnostic imaging choice. Challenges with the VSS technique also exist, such as stent choice and deployment. There are considerations regarding postprocedural balloon angioplasty and pharmacologic treatment, but there is insufficient evidence to formalize postoperative decision making. Although complications of VSS are relatively rare, they include in-stent stenosis, hemorrhage, and subdural hematoma, and the learning curve for VSS presents specific challenges in navigating venous anatomy, emphasizing the need for wider availability of high-quality training. Recurrence of symptoms, particularly stent-adjacent stenosis, poses challenges, and although restenting and cerebrospinal fluid-diverting procedures are options, there is a need for clearer criteria for retreatment strategies. Despite these challenges, when comparing VSS with traditional cerebrospinal fluid-diverting procedures, VSS emerges as a favorable option, with strong clinical outcomes, lower complication rates, and cost-effectiveness. Further research is necessary to refine techniques and indications and address specific aspects of VSS to overcome these challenges.

Future Directions and Innovations in Venous Sinus Stenting.

This review explores the future role of venous sinus stenting (VSS) in the management of idiopathic intracranial hypertension and pulsatile tinnitus. Despite its favorable safety profile and clinical outcomes compared with traditional treatments, VSS is not yet the standard of care for these conditions, lacking high-level evidence data and guidelines for patient selection and indications. Current and recently completed clinical trials are expected to provide data to support the adoption of VSS as a primary treatment option. Additionally, VSS shows potential in treating other conditions, such as dural arteriovenous fistula and cerebral venous sinus thrombosis, and it is likely that the procedure will continue to see an expansion of its approved indications. The current lack of dedicated venous stenting technology is being addressed with promising advancements, which may improve procedural ease and patient outcomes. VSS also offers potential for expansion into modulation of brain electrophysiology via endovascular routes, offering exciting possibilities for neurodiagnostics and treatment of neurodegenerative disorders.

Multiple pipeline embolization devices improves aneurysm occlusion without increasing morbidity: A single center experience of 140 cases.

INTRODUCTION: Rates of aneurysm occlusion with the pipeline embolization device (PED) has varied widely in the literature from 55.7% to 93.3% at 6 months, which may reflect a difference in technique including sizing and number of devices used. METHODS: 140 cases at our institution were retrospectively reviewed, and aneurysms treated with a single PED vs. multiple were compared. RESULTS: Complete aneurysm occlusion was achieved in 86.9% at 6 months, 91.8% at 1 year, and 97.6% at longest follow-up. Retreatment with an additional device was required in 7 (5.1%). Major and minor complication rate within 30 days was 1.4% and 5.0%, and at greater than 30 days was 0.8% and 3.1%. Patients treated with multiple PEDs had significantly higher rates of aneurysm occlusion at 6 months (92.9% vs. 75.6%, p = 0.017) and 12 months (98.4% vs. 81.1%, p = 0.014), with no difference in complications. The two groups were similar aside from a higher number of ophthalmic and paraophthalmic aneurysms treated with multiple PEDs (23.4% vs. 6.5%, p = 0.004; and 35.1% vs. 17.4%, p = 0.020), and more posterior communicating artery and recurrent aneurysms treated with a single PED (28.3% vs. 3.2%, p = 0.001; 23.9% vs. 8.5%, p = 0.031). The use of multiple PEDs was found to be an independent predictor of aneurysm occlusion in a multivariate analysis (p = 0.015). CONCLUSIONS: The use of multiple PEDs for intracranial aneurysms leads to significantly higher occlusion rates without added morbidity. This benefit is particularly appropriate for ophthalmic segment aneurysms, while more distal segments with eloquent perforating branches should be managed with caution.

Double Stent-Assisted (Y and X) Coil Embolization of Unruptured Intracranial Saccular Aneurysms using the Low-Profile Visualized Intraluminal Support Device-Single Center Experience.

PURPOSE: To study the feasibility, safety, and durability of the dual stent-assisted coil embolization (DSCE) technique using low-profile visualized intraluminal support (LVIS) device. METHODS: Retrospective review of our aneurysm database to identify all the patients treated with LVIS stent-assisted embolization between July 2015 and June 2017 was performed. 15% of the patients with Y- or X-configuration DSCE constituted the study population. Patient demographics, clinical presentation, aneurysm characteristics (location, dome, and dome/neck ratio), periprocedural complications, immediate and follow-up angiographic and clinical outcomes were reported. RESULTS: Twelve patients (15%) with unruptured, wide-necked branching aneurysms underwent DSCE using LVIS Junior stents. M:F-1:11. Mean age of 60 ± 11 years. 75% (n = 9) aneurysms are located in anterior circulation. Recurrent aneurysms were treated in 17% (n = 2). Mean aneurysm diameter was 8 ± 3.4 mm and the dome/neck ratio was 1.6 ± 0.4. Periprocedural complications were noted in 25% (n = 3; transient in-stent thrombus = 2 and iatrogenic rupture = 1) with no clinical sequelae. Immediate aneurysm obliteration following DSCE was noted in all (100%) patients. Mean time-of-flight (TOF) magnetic resonance angiography (MRA) follow-up was 10 ± 6 months (Range: 5-19 months). Mean clinical follow-up was 12 ± 6 months (Range: 5-21 months). Stable neck recurrence was demonstrated in 25% (n = 3). The average modified Rankin Score (mRS) at prestent, 24-hour poststent, and last clinical follow-up were: 0.5 (Range: 0-1), 0.75 (Range: 0-1), and 0.5 (Range: 0-1), respectively. CONCLUSION: We report the first dedicated DSCE experience with LVIS Junior stents in the literature. DSCE with LVIS Junior stents for intracranial complex wide-neck branching aneurysms is feasible, safe, and effective with good clinical outcomes.

Pelvic cardiovascular magnetic resonance venography: venous changes with patient position and hydration status.

BACKGROUND: To determine the effect of hydration as well as prone versus supine positioning on the pelvic veins during cardiovascular magnetic resonance (CMR) venography. METHODS: Under institutional review board approval, 8 healthy subjects were imaged with balanced steady state free precession, non-contrast CMR venography to measure common and external iliac vein volumes and common femoral vein cross-sectional area in the supine, prone and decubitus positions after dehydration and again following re-hydration. CMR venography from 23 patients imaged both supine and prone were retrospectively reviewed and measurements of common femoral and iliac veins areas were compared using Wilcoxon test. RESULTS: Common femoral vein area on CMR venography increased with prone positioning (83 ± 35 mm2) compared to supine positioning (59 ± 21 mm2) (p = 0.02) and further increased with hydration to 123 ± 44 mm2 (p < 0.01). With right and left side down decubitus positioning, the common femoral vein area on dehydration increased from 29 ± 17 mm2 in the ante-dependent position to 134 ± 36 mm2 in the dependent position (p < 0. 001). Similarly, common and external iliac veins increased in volume with prone, 5.4 ± 1.9 cm3 and 5.8 ± 1.9 cm3 compared to supine positioning 4.6 ± 1.8 cm3 and 4.5 ± 1.9 cm3 (p = 0.01) and further increase with hydration to 6.7 ± 2.1 cm3 and 6.3 ± 1.9 cm3 (p = 0.01). CMR venography on patients also demonstrated an increase in mean common femoral vein luminal area from 103 ± 44 mm2 in supine position to 151 ± 52 mm2 with prone positioning (p < 0.001) as well as increases in common and external iliac vein volumes from 6.5 ± 2.6 cm3 and 8.0 ± 3.4 cm3 in the supine position to 7.5 ± 2.5 cm3 and 9.3 ± 3.6 cm3 with prone positioning (p < 0.01). CONCLUSIONS: Common femoral and common/external iliac vein size on CMR venography may be affected by position and hydration status. Routine clinical CMR venography of the pelvis could include prone positioning and avoiding dehydration to maximize pelvic vein distension.

Impaired drainage of vein of Labbé following venous sinus stenting for idiopathic intracranial hypertension.

PURPOSE: The impact of venous sinus stenting (VSS) on vein of Labbé (VOL) drainage is poorly understood. The purpose of the study is to examine the incidence and potential high risk factors of impaired VOL drainage among idiopathic intracranial hypertension (IIH) patients following VSS. MATERIALS AND METHODS: Institutional review board approved prospective evaluation of all IIH patients who underwent VSS over a 5 year period (January 2012 to December 2017) at Weill Cornell Medical Center constituted the study population. Patient demographics, procedural details (laterality of stenting, balloon angioplasty, number of stents, and stent diameters), morphology of the VOL and changes in the flow in the VOL, type of sinus stenosis, and transverse sinus symmetry were evaluated. We used χ2 analysis to evaluate impaired VOL drainage against other variables. Statistical significance was set at 0.05. RESULTS: 70 consecutive patients (67 women, 3 men) with a mean age of 31±9.8 years underwent VSS. Stenosis was extrinsic in 63% (n=44) and intrinsic in 37% (n=26) of patients. Impaired drainage of the VOL was detected in 9/70 (13%) patients. Ipsilateral VOL was recognized as dominant in 20% (n=14), co-dominant in 51% (n=36), and non-dominant in 29% (n=20) of patients. Impaired VOL drainage was significantly associated with ipsilateral VOL dominance (P=0.001) and stent diameter of ≥9 mm (P=0.042). All patients demonstrated widely patent VOL on follow-up contrast enhanced MR venography at 3 months and 24 months. CONCLUSION: Impaired drainage of the ipsilateral VOL is a potential consequence of VSS with 13% incidence, and has significant association with ipsilateral superficial cortical venous drainage via dominant VOL and stent diameter of ≥9 mm. CLINICAL TRIAL REGISTRATION: NCT01407809.

Anatomic measurements of cerebral venous sinuses in idiopathic intracranial hypertension patients.

PURPOSE: Magnetic resonance venography (MRV) has not been validated in pre-operative planning of the dural venous sinus stenting (VSS) among idiopathic intracranial hypertension (IIH) patients. We aim to prospectively evaluate dural venous sinus measurement in IIH patient population on two-dimensional time-of-flight (2D-TOF) MRV and Three-dimensional contrast-enhanced (3D-CE) MRV acquisitions and compare them against real-time endoluminal measurements with intravascular ultrasound (IVUS), served as the reference. MATERIALS AND METHODS: The study has been approved by the Weill Cornell Medicine institutional review board. All patients signed written informed consent approved by IRB. Prospective evaluation of forty-five consecutive IIH patients treated with VSS at our institution were evaluated. Patients with pre-stent magnetic resonance venography (MRV) ≤ 6-months of VSS and intravascular ultrasound (IVUS) during VSS constituted the study population. Maximum diameter (in mm), Area (in cm2) and Perimeter (in cm) were measured at posterior 1/3rd of superior sagittal sinus (SSS), proximal transverse sinus (PTS), proximal sigmoid sinus (PSS) and mid sigmoid sinus (MSS) on 2D-TOF-MRV, 3D-CE-MRV and IVUS. Statistical analysis performed using box and whisker plots, Bland-Altman analysis and paired sample t-test. RESULTS: Twenty (n = 20) patients constituted our study population. The mean age was 30±11 years (7-59 years) and 18 out of 20 were female patients. Mean weight and BMI (range) were 86.3±18.3 kilograms (30.8-107.5 kgs) and 32.9±6.8 kg/M2 (16.4-48.3kg/M2) respectively. The CE-MRV significantly oversized the cerebral venous sinuses compared to TOF-MRV (Dmax: +2.0±1.35 mm, p<0.001; Area: +13.31±10.92 mm2, p<0.001 and Perimeter: +4.79±3.4 mm, p<0.001) and IVUS (Dmax: +1.52±2.16 mm, p<0.001; Area: +10.03±21.5 mm2, p<0.001 and Perimeter: +4.15±3.27 mm, p<0.001). The TOF-MRV sinus measurements were in good agreement with the IVUS measurements with no significant variation (Dmax: +.21±2.23 mm, p = 0.49; Area: +2.51±20.41mm2, p = 0.347 and Perimeter: +.001±1.11 mm, p = 0.991). CONCLUSION: We report baseline cerebral venous sinus measurements (maximum diameter, area and perimeter) in patients with idiopathic intracranial hypertension. In our experience, TOF-MRV is a reliable representation of endoluminal cerebral venous sinus dimensions, and CE-MRV measurements reflected an overestimation of the endoluminal sinus dimensions when compared against the real time IVUS measurements.

Pressure variations in cerebral venous sinuses of idiopathic intracranial hypertension patients.

PURPOSE: To evaluate the alteration of pressure characteristics in the cerebral venous sinuses before and after venous sinus stenting (VSS) using mean sinus pressures (MSPs), sinus pressure gradient (SPG), and sinus pressure pulsatility (SPP) parameters among the idiopathic intracranial hypertension (IIH) patients. MATERIALS AND METHODS: Prospective evaluation of 45 consecutive IIH patients who underwent VSS at our institution. A written informed consent approved by the Weill Cornell Institutional Review Board was signed by the study participants. All patients (n = 45) were evaluated for MSPs and SPG. In a subgroup of 12 (n = 12) consecutive patients, SPP was measured. MSP was measured using microcatheter at superior sagittal sinus (SSS), transverse sinus (TS), and sigmoid sinus (SS). SPG was measured as trans-stenotic gradient and trans-torcular gradient. SPP was recorded in the dominant TS with a six French intermediate catheter. Statistical analysis was performed using paired student t-test and two sample t-tests tested for both equal and unequal variances. P values below 0.05 were considered significant. RESULTS: The mean age of the study population was 30.6 ± 10 years (7-59 years) and 43 out of 45 are female patients. The mean weight and BMI of the study population were 96 ± 24.7 kg (30.8-144 kg) and 35.6 ± 8.3 kg/M2 (16.4-51.4 kg/M2), respectively. VSS in IIH patients resulted in immediate reduction of MSP in the SSS {Δ Mean: -8.1 mm Hg [95% confidence interval (CI): -5.0-11.7 mm Hg], p < 0.001} and TS [Δ Mean: -11.8 mm Hg (95% CI: -7.5 to 13.4 mm Hg), p < 0.001] and increase of MSP in SS [Δ Mean: 7.5 mm Hg (95% CI: 6-10.1 mm Hg), p < 0.001]. Significant reduction of trans-stenotic SPG reduction [Δ Mean: -15.7 mm Hg (95% CI: -13.6-17.8 mm Hg), p < 0.001] and SPP [Δ Mean: -8 mm Hg (95% CI: -2.5-13.4 mm Hg), p < 0.05] was observed following VSS. CONCLUSION: VSS resulted in immediate alteration of the cerebral venous sinus pressure measurements in patients with IIH.

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.

Endovascular treatment of middle cerebral artery aneurysms: A single center experience with a focus on thromboembolic complications.

Background Endovascular treatment of middle cerebral artery (MCA) aneurysms has traditionally been considered difficult due to complex branching patterns, frequent involvement of parent vessels within the aneurysm neck, and a high incidence of thromboembolic complications. Methods The cases of 93 MCA aneurysms treated with endovascular intervention at our institution between 2003 and 2015 were retrospectively reviewed. Demographic, clinical, and radiographic variables were recorded and analyzed. Results Immediate complete or near-complete occlusion was achieved in 81 (90%) cases. At the longest follow up of 6 months or greater, 83.3% of the aneurysms were stable-to-improved in the Raymond occlusion classification, 8.3% were found to have minor recanalization not requiring retreatment, and 8.3% required retreatment due to significant recanalization. Thromboembolic events occurred in 18 (19.3%) of cases, but only 1 resulted in permanent vessel occlusion and only 1 resulted in permanent neurologic impairment. Thrombus was resolved with intra-arterial thrombolysis or mechanical thrombectomy in 17 of the 18 cases. There were only two cases resulting in morbidity (2.15%). There was no statistically significant correlation between aneurysm location, size, morphology, or use of adjuvant device with radiographic outcome or thromboembolic event. Conclusions While the rate of thromboembolic events in our series was 19%, the overall morbidity was only 2%. This highlights the fact that even complex MCA aneurysms can safely and effectively be treated by endovascular means with or without the use of balloon or stent assistance, as long as the interventionalist is astutely aware of the possibility of thrombus formation and acts accordingly with thrombolytic therapy when necessary.

Selective ophthalmic artery chemosurgery (SOAC) for retinoblastoma: fluoroscopic time and radiation dose parameters. A baseline study.

OBJECTIVE: To evaluate fluoroscopic time and radiation dose parameters, and factors affecting these parameters, during selective ophthalmic artery chemosurgery (SOAC) for retinoblastoma. MATERIALS AND METHODS: Retrospective review from the prospective database of all patients with retinoblastoma treated with SOAC over a 5-year period (September 2009-January 2015) at a single institution after receiving institutional review board approval. Patient demographics, arterial approach, access device, side of treatment, number of SOAC cycles/patient, number of drugs/SOAC, and radiation parameters (outcome variables), including the fluoroscopic time, dose-area product (DAP), and total radiation dose, were obtained from the database. Generalized linear regression was used for univariate and multivariate analysis of the outcome variables. RESULTS: In 218 patients (M:F=94:124), 272 eyes were treated by 833 SOAC infusions during 792 procedures. Mean age, weight, SOAC cycle/patient, and drugs/cycle were 19±19.5 months, 11.4±6.4 kg, 2.72±1.6, and 2.48±0.8, respectively. Mean fluoroscopic time, DAP, and doses were 10.2±8.4 min, 218.7±240.8 cGy.cm2, and 42.3±41.4 mGy, respectively. Radiation parameters (fluoroscopic time, DAP, and dose) were significantly lower (p<0.001) for the ophthalmic artery (OA) approach (7.5±5.4; 147.7±138.4; 28.5±29.4) than with middle meningeal artery (13.4±5.6; 242±138; 51.4±27) and balloon-assisted infusion in the internal carotid artery (ICA; 17.8±11.5; 449.8±361; 81.8±63.3). Radiation parameters for microcatheter access (8.6±7.1; 193.4±181.3; 42.3±37) were significantly lower (p<0.001) than with the ICA (17.8±11.5; 449.8±361; 81.8±63.3). Radiation parameters for bilateral IA chemotherapy (IAC; 16.8±11.6; 320.7±268.7; 60.8±45.6) were significantly higher (p<0.001) than for unilateral IAC (8.9±6.6; 212.7±247; 42±41). CONCLUSIONS: In SOAC for retinoblastoma, the OA approach, microcatheter access, and unilateral treatment were associated with significantly lower radiation parameters. We established benchmark radiation parameters for retinoblastoma SOAC in our patient cohort.

Automating Perforator Flap MRA and CTA Reporting.

Surgical breast reconstruction after mastectomy requires precise perforator coordinates/dimensions, perforator course, and fat volume in a radiology report. Automatic perforator reporting software was implemented as an OsiriX Digital Imaging and Communications in Medicine (DICOM) viewer plugin. For perforator analysis, the user identifies a reference point (e.g., umbilicus) and marks each perforating artery/vein bundle with multiple region of interest (ROI) points along its course beginning at the muscle-fat interface. Computations using these points and analysis of image data produce content for the report. Post-processing times were compared against conventional/manual methods using de-identified images of 26 patients with surgically confirmed accuracy of perforator locations and caliber. The time from loading source images to completion of report was measured. Significance of differences in mean processing times for this automated approach versus the conventional/manual approach was assessed using a paired t test. The mean conventional reporting time for our radiologists was 76 ± 27 min (median 65 min) compared with 25 ± 6 min (median 25 min) using our OsiriX plugin (p < 0.01). The conventional approach had three reports with transcription errors compared to none with the OsiriX plugin. Otherwise, the reports were similar. In conclusion, automated reporting of perforator magnetic resonance angiography (MRA) studies is faster compared with the standard, manual approach, and transcription errors which are eliminated.

Breast Tissue Expanders with Magnetic Ports: Clinical Experience at 1.5 T.

BACKGROUND: The purpose of this study was to evaluate breast tissue expanders with magnetic ports for safety in patients undergoing abdominal/pelvic magnetic resonance angiography before autologous breast reconstruction. METHODS: Magnetic resonance angiography of the abdomen and pelvis at 1.5 T was performed in 71 patients in prone position with tissue expanders with magnetic ports labeled "MR Unsafe" from July of 2012 to May of 2014. Patients were monitored during magnetic resonance angiography for tissue expander-related symptoms, and the chest wall tissue adjacent to the tissue expander was examined for injury at the time of tissue expander removal for breast reconstruction. Retrospective review of these patients' clinical records was performed. T2-weighted fast spin echo, steady-state free precession and gadolinium-enhanced spoiled gradient echo sequences were assessed for image artifacts. RESULTS: No patient had tissue expander or magnetic port migration during the magnetic resonance examination and none reported pain during scanning. On tissue expander removal (71 patients, 112 implants), the surgeons reported no evidence of tissue damage, and there were no operative complications at those sites of breast reconstruction. CONCLUSION: Magnetic resonance angiography of the abdomen and pelvis in patients with certain breast tissue expanders containing magnetic ports can be performed safely at 1.5 T for pre-autologous flap breast reconstruction perforator vessel mapping. CLINICAL QUESTION/LEVEL OF EVIDENCE: Therapeutic, IV.

Contrast-enhanced time-resolved MRA for pre-angiographic evaluation of suspected spinal dural arterial venous fistulas.

BACKGROUND: Spinal digital subtraction angiography (DSA) is the gold standard for diagnosis of spinal dural arterial venous fistulas (SDAVFs), but can require extensive time, radiation exposure and contrast dose. We hypothesize that contrast-enhanced time-resolved MR angiography (CE-TR MRA) will have utility for the non-invasive diagnosis and pre-angiographic localization of SDAVFs. METHODS: Eighteen patients underwent both CE-TR MRA and DSA for suspected SDAVFs, with DSA performed a median of 11 days (range 0-41) after MRA. CE-TR MRA was performed on a 1.5 T GE unit using Time Resolved Imaging of Contrast Kinetics (TRICKS). CE-TR MRA and DSA images were evaluated for the presence of SDAVFs and location of the feeding arterial supply, with DSA as the reference standard. DSA was also evaluated for the number of vessels catheterized, contrast volume and fluoroscopic and procedure times. RESULTS: Eight of the 18 patients were positive for SDAVF on DSA. Sensitivity, specificity, positive predictive value and negative predictive value for the 18 CE-TR MRAs were 88%, 90%, 88% and 90%, respectively. Localization of the SDAVF arterial supply on CE-TR MRA was within one vertebral level from DSA for 6/7 SDAVFs. Compared with patients with a SDAVF and feeding artery identified on CE-TR MRA, patients with negative or suboptimal CE-TR MRA had a significantly increased number of vessels catheterized (p=0.027) and larger contrast volumes (p=0.022). CONCLUSIONS: CE-TR MRA is a useful initial examination for the diagnosis and localization of SDAVFs, with a high concordance rate with DSA. When CE-TR MRA demonstrates a SDAVF, the number of catheterized vessels and contrast dose can be decreased during DSA.