Venous sinus stenting for reduction of intracranial pressure in IIH: a prospective pilot study

OBJECTIVE

Idiopathic intracranial hypertension (IIH) may cause blindness due to elevated intracranial pressure (ICP). Venous sinus stenosis has been identified in select patients, leading to stenting as a potential treatment, but its effects on global ICP have not been completely defined. The purpose of this pilot study was to assess the effects of venous sinus stenting on ICP in a small group of patients with IIH.

METHODS

Ten patients for whom medical therapy had failed were prospectively followed. Ophthalmological examinations were assessed, and patients with venous sinus stenosis on MR angiography proceeded to catheter angiography, venography with assessment of pressure gradient, and ICP monitoring. Patients with elevated ICP measurements and an elevated pressure gradient across the stenosis were treated with stent placement.

RESULTS

All patients had elevated venous pressure (mean 39.5 ± 14.9 mm Hg), an elevated gradient across the venous sinus stenosis (30.0 ± 13.2 mm Hg), and elevated ICP (42.2 ± 15.9 mm Hg). Following stent placement, all patients had resolution of the stenosis and gradient (1 ± 1 mm Hg). The ICP values showed an immediate decrease (to a mean of 17.0 ± 8.3 mm Hg), and further decreased overnight (to a mean of 8 ± 4.2 mm Hg). All patients had subjective and objective improvement, and all but one improved during follow-up (median 23.4 months; range 15.7–31.6 months). Two patients developed stent-adjacent stenosis; retreatment abolished the stenosis and gradient in both cases. Patients presenting with papilledema had resolution on follow-up funduscopic imaging and optical coherence tomography (OCT) and improvement on visual field testing. Patients presenting with optic atrophy had optic nerve thinning on follow-up OCT, but improved visual fields.

CONCLUSIONS

For selected patients with IIH and venous sinus stenosis with an elevated pressure gradient and elevated ICP, venous sinus stenting results in resolution of the venous pressure gradient, reduction in ICP, and functional, neurological, and ophthalmological improvement. As patients are at risk for stent-adjacent stenosis, further follow-up is necessary to determine long-term outcomes and gain an understanding of venous sinus stenosis as a primary or secondary pathological process behind elevated ICP.

Preoperative Embolization of Cerebral Arteriovenous Malformations with Silk Suture and Particles: Technical Considerations and Outcomes

OBJECTIVE

Embolization of cerebral arteriovenous malformations (AVMs) is commonly performed prior to surgical resection in order to reduce intraoperative bleeding and improve the safety of resection. Although most modern embolization procedures utilize permanent embolic agents, silk suture and polyvinyl alcohol (PVA) particles may offer unique advantages for preoperative devascularization. The aims of this retrospective cohort study are to describe the technical considerations and determine the outcomes for preoperative silk suture and PVA particle embolization (SPE) of AVMs.

MATERIALS AND METHODS

We performed a retrospective review of our AVM embolization database. AVM patients who underwent preoperative SPE and subsequent surgical resection were included for analysis. Baseline patient demographics, AVM characteristics, embolization and operative records, and post-treatment outcomes were reviewed.

RESULTS

A total of 11 patients who underwent 12 preoperative SPE procedures were included for analysis. Five AVMs were ruptured (45%), and the median nidus volume was 3.0 cm3 (range: 1.3-42.9 cm³). The Spetzler-Martin grade was I-II in seven patients (64%) and III-IV in four patients (36%). The degree of nidal obliteration was less than 25% in two procedures (17%), 25-50% in one procedure (8%), 50-75% in eight procedures (67%), and greater than 75% in one procedure (8%). The rates of post-embolization AVM hemorrhage and mortality were 8% and 0%, respectively. The postoperative angiographic obliteration rate was 100%, and the modified Rankin Scale score improved or stable in 91% of patients (median follow-up duration 2 months).

CONCLUSION

Preoperative AVM SPE affords a reasonable risk to benefit profile for appropriately selected patients.

Clinical efficacy of 2-phase versus 4-phase computed tomography for localization in primary hyperparathyroidism

BACKGROUND

Four-dimensional computed tomography is being used increasingly for localization of abnormal glands in primary hyperparathyroidism. We hypothesized that compared with traditional 4-phase imaging, 2-phase imaging would halve the radiation dose without compromising parathyroid localization and clinical outcomes.

METHODS

A transition from 4-phase to 2-phase imaging was instituted between 2009 and 2010. A pre-post analysis was performed on patients undergoing operative treatment with a parathyroid protocol computed tomography, and relevant data were correlated with operative findings. Sensitivity, positive predictive value, technical success, and cure rates were calculated. The Fisher exact test or χ(2) test assessed the significance of 2-phase and 4-phase imaging and operative findings.

RESULTS

Twenty-seven patients had traditional four-dimensional computed tomography and 35 had modified 2-phase computed tomography. Effective radiation doses were 6.8 mSy for 2-phase and 14 mSv for 4-phase. Four-phase computed tomography had a sensitivity and positive predictive value of 93% and 96%, respectively. Two-phase computed tomography had a comparable sensitivity and positive predictive value of 97% and 94%, respectively. Eight patients with discordant imaging had an average parathyroid weight of 240 g compared with 1,300 g for all patients. Technical surgical success (90% for 4-phase computed tomography versus 91% 2-phase computed tomography) and normocalcemia rates at 6 months (88% for both) did not differ between computed tomography protocols. Computed tomography correctly predicted multiglandular disease and localization for reoperations in 88% and 90% of cases, respectively, with no difference by computed tomography protocol.

CONCLUSION

With regard to surgical outcomes and localization, 2-phase parathyroid computed tomography is equivalent to 4-phase for parathyroid localization, including small adenomas, reoperative cases, and multiglandular disease. Two-phase parathyroid computed tomography for operative planning should be considered to avoid unnecessary radiation exposure.

Optimal Symmetric Multimodal Templates and Concatenated Random Forests for Supervised Brain Tumor Segmentation (Simplified) with ANTsR

Segmenting and quantifying gliomas from MRI is an important task for diagnosis, planning intervention, and for tracking tumor changes over time. However, this task is complicated by the lack of prior knowledge concerning tumor location, spatial extent, shape, possible displacement of normal tissue, and intensity signature. To accommodate such complications, we introduce a framework for supervised segmentation based on multiple modality intensity, geometry, and asymmetry feature sets. These features drive a supervised whole-brain and tumor segmentation approach based on random forest-derived probabilities. The asymmetry-related features (based on optimal symmetric multimodal templates) demonstrate excellent discriminative properties within this framework. We also gain performance by generating probability maps from random forest models and using these maps for a refining Markov random field regularized probabilistic segmentation. This strategy allows us to interface the supervised learning capabilities of the random forest model with regularized probabilistic segmentation using the recently developed ANTsR package--a comprehensive statistical and visualization interface between the popular Advanced Normalization Tools (ANTs) and the R statistical project. The reported algorithmic framework was the top-performing entry in the MICCAI 2013 Multimodal Brain Tumor Segmentation challenge. The challenge data were widely varying consisting of both high-grade and low-grade glioma tumor four-modality MRI from five different institutions. Average Dice overlap measures for the final algorithmic assessment were 0.87, 0.78, and 0.74 for "complete", "core", and "enhanced" tumor components, respectively.

Prevalence of dural venous sinus stenosis and hypoplasia in a generalized population

Background and purpose

While recent literature has described the prevalence of transverse sinus stenosis in patients with idiopathic intracranial hypertension, tinnitus, and refractory headaches, it is unclear what the prevalence is in the general population. This study evaluates the prevalence of venous sinus stenosis and hypoplasia in the general patient population.

Materials and methods

355 of 600 consecutive patients who underwent CT angiography of the head met the inclusion criteria. The diameters of the dural venous sinuses were recorded. Each study was evaluated by a neuroradiologist for the presence of stenoses. Univariate and multivariate statistical analyses were performed by a statistician.

Results

The prevalence of unilateral transverse sinus stenosis or hypoplasia in a sample of patients representing the general population was 33%, the prevalence of bilateral transverse sinus stenosis was 5%, and the prevalence of unilateral stenosis with contralateral hypoplasia was 1%. A multivariate analysis identified arachnoid granulations as a predictor of stenosis (p<0.001). Gender trended toward significance (p=0.094). Race was not a significant predictor of stenosis (p=0.745).

Conclusions

The prevalence of bilateral transverse sinus stenosis in the general population is not trivial. These data may be used as a reference for understanding the mechanistic role of stenoses in idiopathic intracranial hypertension, tinnitus, and refractory headaches.

Endovascular Treatment of a Fusiform Aneurysm at the M3-M4 Junction of the Middle Cerebral Artery Using the Pipeline Embolization Device

BACKGROUND

Peripheral fusiform cerebral aneurysms remain difficult to treat. Current surgical approaches to the treatment of fusiform aneurysms include wrapping, clip occlusion or vessel reconstruction without parent vessel sacrifice, and aneurysm trapping with or without bypass, although these may carry high morbidity (36%). Classic endovascular approaches to the treatment of peripheral aneurysms include selective or parent artery occlusion, which imparts the risk of distal infarction. It may be possible to use a flow diversion device off label to treat the aneurysm and preserve flow to the distal territory.

CASE DESCRIPTION

After a presyncopal event, a patient was found to have an unruptured fusiform aneurysm at the junction of the M3 and M4 segments of the right middle cerebral artery. After initiating dual antiplatelet therapy, the aneurysm was successfully treated with a Pipeline embolization device. Three months after treatment, the aneurysm has completely thrombosed, the parent artery remains widely patent, and the patient remains at her neurologic baseline.

CONCLUSIONS

Flow diversion devices may provide the neurointerventional surgeon with an opportunity to treat fusiform peripheral aneurysms and preserve flow to the distal territory.

The Multimodal Brain Tumor Image Segmentation Benchmark (BRATS)

In this paper we report the set-up and results of the Multimodal Brain Tumor Image Segmentation Benchmark (BRATS) organized in conjunction with the MICCAI 2012 and 2013 conferences. Twenty state-of-the-art tumor segmentation algorithms were applied to a set of 65 multi-contrast MR scans of low- and high-grade glioma patients-manually annotated by up to four raters-and to 65 comparable scans generated using tumor image simulation software. Quantitative evaluations revealed considerable disagreement between the human raters in segmenting various tumor sub-regions (Dice scores in the range 74%-85%), illustrating the difficulty of this task. We found that different algorithms worked best for different sub-regions (reaching performance comparable to human inter-rater variability), but that no single algorithm ranked in the top for all sub-regions simultaneously. Fusing several good algorithms using a hierarchical majority vote yielded segmentations that consistently ranked above all individual algorithms, indicating remaining opportunities for further methodological improvements. The BRATS image data and manual annotations continue to be publicly available through an online evaluation system as an ongoing benchmarking resource.

Endovascular treatment of ophthalmic artery aneurysms: ophthalmic artery patency following flow diversion versus coil embolization

BACKGROUND AND PURPOSE

The Pipeline Embolization Device (PED) has been shown to effectively treat complex internal carotid artery aneurysms while maintaining patency of covered side branches. The purpose of this retrospective matched cohort study is to evaluate the effect of flow diversion on the patency of the ophthalmic artery when treating ophthalmic artery aneurysms.

METHODS

A retrospective review of our prospectively collected institutional database identified 19 ophthalmic artery aneurysms treated with a PED. These were matched according to aneurysm diameter in a 1:2 fashion to ophthalmic artery aneurysms treated via coil embolization, although it is important to note that there was a statistically significance difference in the neck diameter between the two groups (p=0.045). Clinical and angiographic outcomes were recorded and analyzed.

RESULTS

On follow-up angiography, decreased flow through the ophthalmic artery was observed in 26% of the PED cohort and 0% of the coil embolization cohort (p=0.003). No ophthalmologic complications were noted in either cohort. Complete occlusion at 12 months was more common following PED treatment than coil embolization (74% vs 47%; p=0.089), although lower than reported in previous trials. This may be due to inflow into the ophthalmic artery keeping the aneurysm patent. Retreatments were more common following coil embolization than PED (24% vs 11%), but this was not significant (p=0.304). Permanent morbidity rates were not significantly different between the PED (11%) and coil embolization (3%) cohorts (p=0.255).

CONCLUSIONS

Our results suggest that ophthalmic artery aneurysms may be adequately and safely treated with either the PED or coil embolization. However, treatment with the PED carries a higher risk of impeding flow to the ophthalmic artery, although this did not result in clinical sequelae in the current study.

Combined microsurgical PICA-PICA bypass and endovascular parent artery occlusion for a ruptured dissecting vertebral artery aneurysm

Dissecting vertebral artery (VA) aneurysms are difficult to obliterate when the parent artery cannot be safely occluded. In this video, we demonstrate a combined microsurgical and endovascular treatment technique for a ruptured, dissecting VA aneurysm incorporating the origin of the posterior inferior cerebellar artery (PICA). We first performed a PICA-PICA side-to-side bypass to preserve flow through the right PICA. An endovascular approach was then utilized to embolize the proximal portion of the aneurysm from the right VA and the distal portion of the aneurysm from the left VA. The video can be found here: http://youtu.be/dkkKsX2BiJI .

Embolization of cerebral arteriovenous malformations with silk suture particles prior to stereotactic radiosurgery

We aimed to determine the long term durability of silk suture and polyvinyl alcohol (PVA) particle embolization (SPE) of arteriovenous malformations (AVM), and to evaluate the outcomes following multimodality management of AVM with combined SPE and stereotactic radiosurgery (SRS). A general supposition among neurointerventionalists is that embolization of cerebral AVM with silk sutures and PVA particles does not yield a durable occlusion. We performed a retrospective review of all AVM patients treated at our institution with combined SPE and SRS. After extracting the baseline, embolization and SRS data for each patient, the durability of SPE was determined by evaluating the postembolization recanalization between the last procedural angiogram and the most recent neuroimaging. Four AVM patients who underwent a total of nine SPE procedures through 21 arterial pedicles were included for the analyses. The nidus volumes were 5.8-75 cm(3) and the Spetzler-Martin grades were II and V in one patient and III in two patients. The median degree of devascularization per procedure was <25%. There were no procedural complications, with all patients maintaining functional independence after embolization (modified Rankin scale score 0-2). After a median follow-up duration of 27 months (range: 23-36), there were no patients with recanalization. SRS (marginal dose 13-18 Gy) resulted in 40 to >95% volume reduction. Following SRS, one patient remained asymptomatic, two patients improved, and one patient deteriorated due to a latency period AVM hemorrhage. In conclusion, SPE can safely provide durable AVM devascularization, therefore, appropriately selected nidi can be effectively treated with combined SPE and SRS.

Noninvasive evaluation of the regional variations of GABA using magnetic resonance spectroscopy at 3 Tesla

PURPOSE

Rapid regional fluctuations in GABA may result in inhomogeneous concentrations throughout the brain parenchyma. The goal of this study is to provide further insight into the natural distribution of GABA throughout the brain and thus determine if a surrogate site may be used for spectroscopy when evaluating motor diseases, neurological disorders, or psychiatric dysfunction.

MATERIALS AND METHODS

In this prospective study, eight healthy volunteers underwent spectroscopic evaluation of the frontal lobe, occipital lobe, lateral temporal lobe, basal ganglia, and both hippocampi using a spin echo variant of a J-difference editing method. Knowledge of the relative peak intensities of the macromolecule peaks at 3ppm and 0.9ppm was used to correct the contribution of co-edited macromolecules to the GABA peak at 3ppm. The GABA values were internally referenced to NAA. Linear regression was used to normalize the effect of regional tissue-fraction variation on the GABA/NAA values. A one-way ANOVA was performed with Tukey's multiple comparison test to compare the normalized GABA/NAA values in each pair of locations.

RESULTS

After accounting for the macromolecule contribution to the GABA signal and correction for tissue fraction variation, the normalized GABA/NAA ratios differ significantly between the six brain locations (p<0.001). Pairwise comparisons of the corrected normalized GABA/NAA ratios show statistically significant variation between the frontal lobe and the basal ganglia, frontal and lateral temporal lobes, and frontal lobe and right hippocampus. Variations in the normalized GABA/NAA ratios trend toward significance between the frontal lobe and left hippocampus, occipital lobe and the frontal lobe, occipital lobe and basal ganglia, and occipital lobe and right hippocampus.

CONCLUSION

Our study suggests that GABA concentration is inhomogeneous throughout the parenchyma. Studies evaluating the role of GABA must carefully consider voxel placement when incorporating spectroscopy.

Modification of a Braided Support Catheter into a Rapid Exchange System for Navigation of a Distal Protection Device through Significant Vascular Tortuosity

Cerebral embolic protection devices (EPD) reduce the rate of periprocedural thromboembolic complications and are currently used in all carotid artery stenting (CAS) procedures. However, tortuous vascular anatomy of the internal carotid artery (ICA) may prevent navigation of distal EPDs, thereby leading to inadequate cerebral protection. We present a case in which significant tortuosity of the ICA distal to the stenotic lesion precluded navigation of currently available distal EPDs. During a CAS procedure, significant vascular tortuosity of the distal cervical ICA was noted which prevented navigation of currently available distal EPDs due to catheter kinking. In order to overcome this anatomic barrier, a novel rapid exchange catheter system (RECS) was created using a modified DAC 038 braided catheter through which a distal EPD and microguidewire were placed. This newly devised RECS allowed navigation of the distal EPD past the tortuous ICA bend and successful completion of the CAS procedure without periprocedural complications. We demonstrate that modification of currently available devices can, in select cases, effectively address cases of significant vascular tortuosity which limit the use of conventional distal EPDs.

Evolution of endovascular mechanical thrombectomy for acute ischemic stroke

Acute ischemic stroke (AIS) is a common medical problem associated with significant morbidity and mortality worldwide. A small proportion of AIS patients meet eligibility criteria for intravenous thrombolysis (IVT) with recombinant tissue plasminogen activator, and its efficacy for large vessel occlusion is poor. Therefore, an increasing number of patients with AIS are being treated with endovascular mechanical thrombectomy when IVT is ineffective or contraindicated. Rapid advancement in catheter-based and endovascular device technology has led to significant improvements in rates of cerebral reperfusion with these devices. Stentrievers and modern aspiration catheters have now surpassed earlier generation devices in the degree and rapidity of revascularization. This progress has been achieved with no concurrent increase in risk of major complications or mortality, both when used alone or in combination with IVT. The initial randomized controlled trials comparing endovascular therapy to IVT for AIS failed to show superior outcomes with endovascular treatment, but key limitations of each trial may limit the significance of these results to current practice. While endovascular devices and operator experience continue to evolve, we are optimistic that this will be accompanied by improvements in patient outcomes. This review highlights the major endovascular devices used in current practice and the trials which have investigated their efficacy.

Vision outcomes and major complications after endovascular coil embolization of ophthalmic segment aneurysms

BACKGROUND AND PURPOSE

As aneurysms arising from the ophthalmic segment of the internal carotid artery increase in size, they can compress the optic nerve, prompting patients to present with visual disturbances. The purpose of this article is to describe the clinical and angiographic results with an emphasis on visual outcomes following the endovascular treatment of ophthalmic segment ICA aneurysms.

MATERIALS AND METHODS

The records of 1254 patients who presented for endovascular treatment of a cerebral aneurysm were retrospectively reviewed to identify 65 consecutive patients who underwent coil embolization of an ophthalmic segment ICA aneurysm. The clinical records, treatment reports, and imaging were reviewed with a focus on visual outcomes.

RESULTS

Twenty-two of the 65 patients (34%) who presented for treatment of an ophthalmic aneurysm reported a visual disturbance at presentation. Fifteen of the 22 patients (68%) experienced an improvement in their symptoms after treatment. Overall, patients with visual symptoms were significantly more likely to benefit from treatment than to have a decline in vision (P = .03). The overall morbidity was 4%, and mortality was 0%. The retreatment rate was high at 30%, though this was disproportionately weighted by an 86% retreatment rate in patients with ruptured aneurysms.

CONCLUSIONS

Patients with visual symptoms attributable to ophthalmic segment ICA aneurysms undergoing endovascular coil embolization were statistically more likely to experience an improvement in their vision than to have worsening or unchanged vision. Coiling was associated with a low morbidity rate, though an elevated retreatment rate.

Single-center experience with a dual microcatheter technique for the endovascular treatment of wide-necked aneurysms

Object

The endovascular treatment of wide-necked aneurysms can be technically challenging due to distal coil migration or impingement of the parent vessel. In this paper, the authors illustrate an alternative method for the treatment of wide-necked intracranial aneurysms using a dual microcatheter technique.

Methods

The authors' first 100 consecutive patients who underwent coil embolization of a wide-necked aneurysm using a dual microcatheter technique are reported. With this technique, 2 microcatheters are used to introduce coils into the aneurysm. The coils are deployed either sequentially or concurrently to form a stable construct and prevent coil herniation or migration. Angiographic and clinical outcomes are reported.

Results

The technical success rate of the dual microcatheter technique is 91% with a morbidity and mortality of 1% and 2%, respectively. Clinical outcomes are excellent with 93% of patients demonstrating a modified Rankin Scale score of 0–2 at long-term follow-up regardless of their score at presentation. Retreatment rates are 18%.

Conclusions

The dual microcatheter technique may be a safe and efficacious first line of treatment for widenecked aneurysms.

Venous stenting with concurrent intracranial pressure monitoring for the treatment of pseudotumor cerebri

Increasing evidence supports dural venous sinus stenosis as the patho-etiology of pseudotumor cerebri (PTC) in a subset of affected patients. In this video, we demonstrate our technique for 1) diagnostic venous manometry to identify a flow-limiting stenosis of the transverse sinus in a PTC patient; and 2) successful treatment of the patient with venous stenting across the structural and physiological stricture in the dural sinus. The pressure gradient decreased from 20 mmHg pre-stent to 3 mmHg post-stent. In order to further quantify the effect of our intervention, concurrent intracranial pressure monitoring was performed.

The video can be found here: http://youtu.be/auxRg17F8yI.

Dynamic CT for parathyroid disease: are multiple phases necessary?

BACKGROUND AND PURPOSE

A 4D CT protocol for detection of parathyroid lesions involves obtaining unenhanced, arterial, early, and delayed venous phase images. The aim of the study was to determine the ideal combination of phases that would minimize radiation dose without sacrificing diagnostic accuracy.

MATERIALS AND METHODS

With institutional review board approval, the records of 29 patients with primary hyperparathyroidism who had undergone surgical exploration were reviewed. Four neuroradiologists who were blinded to the surgical outcome reviewed the imaging studies in 5 combinations (unenhanced and arterial phase; unenhanced, arterial, and early venous; all 4 phases; arterial alone; arterial and early venous phases) with an interval of at least 7 days between each review. The accuracy of interpretation in lateralizing an abnormality to the side of the neck (right, left, ectopic) and localizing it to a quadrant in the neck (right or left upper, right or left lower) was evaluated.

RESULTS

The lateralization and localization accuracy (90.5% and 91.5%, respectively) of the arterial phase alone was comparable with the other combinations of phases. There was no statistically significant difference among the different combinations of phases in their ability to lateralize or localize adenomas to a quadrant (P = .976 and .996, respectively).

CONCLUSIONS

Assessment of a small group of patients shows that adequate diagnostic accuracy for parathyroid adenoma localization may be achievable by obtaining arterial phase images alone. If this outcome can be validated prospectively in a larger group of patients, then the radiation dose can potentially be reduced to one-fourth of what would otherwise be administered.

Stenting of symptomatic intracranial stenosis using balloon mounted coronary stents: a single center experience

OBJECTIVE

Intracranial atherosclerotic disease is the cause of up to 10% of ischemic strokes and transient ischemic attacks. Intracranial stenting with off-label balloon mounted coronary stents (BMCS) may be a viable alternative for patients with symptomatic intracranial stenosis who fail best medical therapy.

DESIGN

Between December 2005 and June 2012, 42 symptomatic intracranial stenoses were treated with a BMCS after failing medical management. Procedural records, clinical outcomes, and imaging follow-up were reviewed. Outcome measurements included technical success rate, morbidity and mortality, long term stent patency, and clinical outcomes, as measured by the modified Rankin Scale.

RESULTS

The technical success rate was 98% (41 of 42 lesions). Morbidity within the first 30 days was 7.1% (three of 42 lesions). Overall morbidity, including both periprocedural and long term evaluation, was 9.5% (four of 42 lesions). There were no deaths. Follow-up imaging was available for 30 stents (71%) with an average follow-up time of 35.1 months. Restenosis (>50%) and retreatment were observed in 20% and 10% of cases, respectively. Clinical evaluation by a neurologist ≥ 30 days postprocedure was available in 40 of 42 cases (95%) with an average of 32.1 months. At presentation, 55% of patients had a modified Rankin Scale (mRS) score of ≤ 2. At follow-up, 74% of patients were found to have an mRS score of ≤ 2.

CONCLUSIONS

This study suggests that BMCS may benefit patients with symptomatic intracranial stenosis who experience stroke or transient ischemic attack in spite of best medical therapy.

Persistent trigeminal artery: in situ thrombosis and associated perforating vessel infarction

We report a patient with progressive brainstem infarction despite medical therapy. The patient was transferred to our institution for potential angioplasty of basilar stenosis. Imaging review demonstrated persistent trigeminal artery in situ thrombosis and associated perforating vessel infarction. Persistent trigeminal arteries are commonly associated with an atretic basilar artery and interventional treatment can result in significant morbidity and mortality.