Vertebro-Vertebral Arteriovenous Fistulae: A Case Series of Endovascular Management at a Single Center.

OBJECTIVE: Vertebro-vertebral arteriovenous fistulae (VVFs) are a rare disorder characterized by a direct shunt between the extracranial vertebral artery and the veins of the vertebral venous plexus. This study aims to comprehensively review the characteristics and outcomes of endovascular treatments for VVFs at our center. METHODS: A retrospective review was conducted on 14 patients diagnosed with a VVF who underwent endovascular treatment at Siriraj Hospital from January 2000 to January 2023. The study assessed patient demographics, presentation, fistula location, treatment strategies, endovascular techniques employed, and treatment outcomes. RESULTS: Among the 14 patients, 11 (78.6%) were female, with an age range from 25 to 79 years (median: 50 years). Spontaneous VVFs were observed in 64.3% of the cases, including three associated with neurofibromatosis type 1 (NF-1). Iatrogenic injury accounted for two cases, and three patients had VVFs resulting from traffic accidents. A pulsatile neck mass and tinnitus, with or without neurological deficits, were common presenting symptoms. Active bleeding was observed in three cases with vascular injury, while unilateral proptosis, congestive heart failure, and incidental findings each presented in one patient. All the VVFs were successfully obliterated without major treatment complications. Parent vessel sacrifice was performed in 85.7% of the cases, while vertebral artery preservation was achieved in the remaining two patients. Embolic materials included detachable balloons, detachable coils, and n-butyl cyanoacrylate (NBCA) glue. All the presenting symptoms showed improvement, and no morbidity or mortality was observed. CONCLUSIONS: Endovascular embolization is a feasible and effective approach for achieving complete VVF obliteration with safety. Parent artery sacrifice should not be reluctantly performed, particularly when adequate collateral circulation is demonstrated.

Treatment Outcomes of Mechanical Thrombectomy in Patients with Acute Posterior Circulation Stroke.

Objective The benefits of mechanical thrombectomy (MT) in patients with acute posterior circulation stroke remain unclear. Currently, there is no evidence from randomized control trials to show the safety and effectiveness of MT in patients with posterior circulation stroke. This study was to evaluate the treatment outcomes of MT in posterior circulation stroke patients enrolling in our hospital during 2010 to 2020. Materials and Methods Between January 2010 and December 2020, 66 patients with acute posterior circulation stroke underwent MT. Data collected and analyzed included demographics, comorbidity, National Institutes of Health Stroke Scale (NIHSS), procedure time, site of occlusion, presence of posterior communicating artery (PCoA), endovascular technique, and modified Rankin Scale (mRS). Good clinical outcome was defined by mRS at 2 or less at 90 days after MT. Statistical Analysis Variables with normal distribution were reported with mean ± standard deviation, meanwhile those with nonnormal distribution were demonstrated with median and range. Fisher's exact test for categorical variables or Mann-Whitney U test for continuous variables was performed. Multivariate logistic regression analysis with binary logistic regression method was used analyze the association between the prognosis factor and good outcome. Statistical significance was defined when p -value less than 0.05. Results The mean age of patients was 65.2 years with male predominance. The median NIHSS was 18.5. Successful recanalization (modified thrombolysis in cerebral infarction 2b-3) was achieved in 61/66 cases (92.42%) and postprocedure symptomatic intracerebral hemorrhage occurred in 5/66 cases (7.60%). Successful recanalization with good clinical outcome was obtained from 30 of 61 cases (49.18%); it was also associated with distal basilar artery occlusion ( p = 0.035) and PCoA patency presence ( p = 0.024). Our study showed the correlation between good treatment outcomes with initial NIHSS less than 20, intravenous recombinant tissue-type plasminogen activator, pre-MT magnetic resonance imaging Q5 brain, and contact aspiration MT technique. Conclusion MT is beneficial to patients with posterior circulation stroke. A good clinical outcome was significantly associated with distal basilar artery occlusion and PCoA patency presence within a group of successful recanalization.

Infundibular dilatation perforating vessel of anterior communicating artery.

Background: Infundibular dilatation at cerebral arteries is primary located at the posterior communicating artery. This report describes a rare case of infundibular dilatation perforating the branch of an anterior communication artery (AcomA) which mimicked an AcomA aneurysm. Case Description: The 54-year-old female presented with acute headache in the left temporal area with the right hemianesthesia. The magnetic resonance imaging and magnetic resonance angiography of the brain revealed a small outpouching lesion arising from the medial wall of the proximal A2 of the left ACA presenting as a suspected AcomA aneurysm. The cerebral angiogram showed a funnel-shaped dilatation of the anterior communicating artery with a single perforating branch arising from a dome size 1.4 × 1.1 mm, compatible with an infundibular dilatation perforating a branch of the AcomA. Conclusion: The infundibular dilatation perforating vessel of AcomA is a rare condition and can mimic an AcomA aneurysm. Three-dimensional angiography helps to evaluate differentiation of the characteristics enabling accurate diagnosis.

Efficiency of Endovascular Therapy for Bilateral Cavernous Sinus Dural Arteriovenous Fistula.

BACKGROUND: The principles of endovascular treatment of bilateral cavernous sinus dural arteriovenous fistula (CS-dAVF) are not well established because of the complexity in the number of fistula tracts and their behavior, which seems to be more aggressive. We aimed to determine an efficient technique for endovascular treatment of bilateral CS-dAVF and the associated factors to achieve good clinical and angiographic outcomes. METHODS: The data were analyzed from 165 consecutive patients diagnosed with CS-dAVF from January 2005 to September 2018. The demographic data included approaching route, embolization times, embolization material, sequence of embolization, number of embolization sessions, and angiographic and clinical outcomes. Interrater agreement of bilateral CS-dAVF diagnosis was performed using the κ coefficient. The factors associated with treatment outcome were analyzed using a Pearson χ2 test. RESULTS: Bilateral CS-dAVF was detected in 43 patients (26%). Angiographic presentations that showed evidence of sinus thrombosis, dangerous venous drainage, and higher Satomi classification were more commonly found in bilateral CS-dAVF than in unilateral CS-dAVF. Good clinical outcome and cure from angiography were obtained in 90% and 74%, respectively. Ipsilateral inferior petrosal sinus-intercavernous sinus-contralateral cavernous sinus catheterization was the major approach route of treatment. The factors associated with improved clinical outcome were transvenous approach, shunt closure, coil embolization, and sequencing the embolization (P < 0.001). CONCLUSIONS: Dangerous venous drainage tends to increase in bilateral CS-dAVF. Retrograde ipsilateral inferior petrosal sinus catheterization using coil embolization and sequencing the embolization are the major concerns for treatment.

Success Rate of Simple Coil Embolization in Wide-Neck Aneurysm with Aneurysmal Shoulder.

BACKGROUND AND OBJECTIVE: Wide-necked intracranial aneurysm (WIA) is one of the challenging diseases for neuro-interventionist to treat by simple coiling technique. The purpose of this study is to identify the morphology associated with successful simple coil embolization in wide neck aneurysm patients. MATERIALS AND METHODS: Between January 2002 and August 2018, 102 patients with total 115 ruptured or unruptured WIA which received endovascular treatment were retrospective reviewed. Data were analyzed including demographics, aneurysm morphology, endovascular technique, angiographic outcome, complication, regrowth, and retreatment rate. RESULTS: The mean age of patients was 61.6 years with female predominant (72.5%). Ruptured WIA was diagnosed in 71 patients (61.7%). Majority of aneurysms were located in an anterior circulation which were 74 cases (64.3%), mainly paraclinoid aneurysm (30/115). Endovascular treatment was successful in 113 cases (98.3%) which can be mainly divided into simple coil embolization 50 cases (43.5%), balloon-assisted coil embolization 26 cases (22.6%), and stent-assisted coil embolization 32 cases (27.8%). Complete, subtotal, and incomplete occlusion of WIA was achieved in 32 cases (27.8%), 62 cases (53.9%), and 18 cases (15.7%), respectively. There was 9.6% complication occurred. Regrowth and retreatment were found 20% and 15.7%, respectively. CONCLUSION: WIA with two-sided aneurysmal shoulder or neck width <3.6 mm. are significantly associated with successful coil embolization using simple coiling technique.

The Effectiveness of Dural Venous Sinus Sacrifice as a Treatment of Aggressive Type Cranial Dural Arteriovenous Fistulas.

OBJECTIVE: To evaluate the effectiveness of dural venous sinus sacrifice as a treatment of aggressive type cranial dural arteriovenous fistulas (dAVFs) in terms of both clinical outcome and angiographic outcome. MATERIALS AND METHODS: One hundred and twenty-eight patients with 163 aggressive type cranial dAVFs who were treated with dural sinus sacrifice were retrospectively reviewed. Clinical and angiographic outcomes were analyzed. Procedural complications were also recorded. Only 103 patients (80.5%) who had been following up for at least 90 days were analyzed for clinical outcome. RESULTS: There were 53 males and 75 females with age ranging from 20 years to 93 years (mean age 55.44 years). The overall angiographic cure rate of dural venous sinus sacrifice as a part of the treatment of aggressive dAVFs was 81.6%. Considering clinical outcome (average duration of follow-up was 2 years and 6 months), 75 patients (72.8%) had clinical improvement and 21 (20.4%) were clinically stable. Worsening of the presenting symptoms was observed in 7 patients (6.8%). Procedural complications were found in 5 patients (3.9%). CONCLUSION: Dural venous sinus sacrifice is a safe and effective treatment strategy with high angiographic cure rate, good clinical outcome, and low incidence of procedural-related complication.

Feasibility Study of Language Lateralization using Thai Version of Language Paradigm for Functional MRI in Clinical Service.

Objective: To evaluate the concordance of language lateralization between functional magnetic resonance imaging (fMRI) using Thai version of language paradigm and Wada test or awake surgery with direct cortical brain stimulation (DCS). Material and Method: Retrospective study of thirteen patients (3 males and 10 females with mean age of 33.9 years old) with epilepsy (7 cases) or brain tumor (6 cases) was performed. Every patient underwent both fMRI (word generation, verb generation, naming picture, and sentence completion tasks) and Wada test or awake surgery with DCS (defined as the gold standard). The lateralization index (LI) of fMRI was automatically calculated by using the LI-toolbox on SPM8. The hemispheric lateralization was also evaluated visually. The concordance between fMRI and gold standard were analyzed. Results: The concordance between the lateralization of fMRI by visual assessment and gold standard was 92.3%. Concordance between the calculated LI by fMRI and gold standard was varied along with the task and regional calculation method. The concordance was good in all tasks (except for naming picture task) when using calculated LI from frontal or whole brain excluded cerebellum and occipital lobe (range 76.92 to 88.98% and 76.92 to 92.31%, respectively). Conclusion: There was good concordance between fMRI and gold standard. Regional calculation from frontal lobes and whole brain excluded cerebellum and occipital lobes gave the best results. The results supported feasibility to use the fMRI with Thai language paradigm as an alternative way to determine the language dominant hemisphere in Thai patients. In case of language dominant hemisphere is unclear, further invasive investigation of language mapping such as Wada test or DCS is crucial.

Computerized Tomographic Angiography for Detection of Cerebral Vasospasm after Ruptured Intracranial Aneurysm.

OBJECTIVE: Digital subtraction angiography (DSA) is the gold standard to diagnose cerebral vasospasm but it is usually not available due to lack of expertise and proper equipment. The present study aimed to compare the diagnostic accuracy of brain computerized tomographic angiography (CTA) in detecting cerebral vasospasm after intracranial aneurysmal rupture. MATERIAL AND METHOD: Between January 2011 and October 2014, 20 patients who were suspected of cerebral vasospasm after aneurysmal subarachnoid hemorrhage (SAH) were prospectively enrolled. All patients underwent brain CTA andDSA within 24 hours after clinical onset ofvasospasm. Separate reviewers independently reviewed the CTA and DSA. RESULTS: Twenty patients were enrolled, including 7 males and 13 females. The patient characteristics did not have any relationship to the incidence of cerebral vasospasm. The CTA finding of vasospasm was well correlated to the DSA finding (Kappa 0.793). Diagnostic accuracy and false negative of the CTA were 90% and 5%, respectively. Sensitivity of the CTA was 94% and specificity was 100%. Positive predictive value ofthe CTA was 100% and negative predictive value was 66%. The vessels that showed the most correlation between the CTA and DSA findings were left A1 (Kappa 0.684) and left A2 (Kappa 0.663) segments of anterior cerebral artery, and left M1 (Kappa 0.503) segment of middle cerebral artery. Both CTA and DSA can detect mild vasospasm (< 50% luminal stenosis) located proximal to the circle of Willis. CONCLUSION: Compared to the DSA, the CTA can be used for detecting cerebral vasospasm in patients with ruptured intracranial aneurysms with high sensitivity, specificity, and diagnostic accuracy.

De novo aneurysm on the posterior cerebral artery: a case report and literature review.

De novo aneurysm formation is a rare entity of cerebral aneurysms. The authors describe a 19-year-old man presenting with spontaneous intracerebral hemorrhage of unknown etiology. The initial cerebral angiography revealed no identifiable vascular lesion. A few weeks following a surgical evacuation of the hematoma, a tiny saccular aneurysm was incidentally found on the distal posterior cerebral artery (PCA) remote from the site of the primary ictus. Several rationales indicated that it was compatible with a cerebral aneurysm of infective etiology. The aneurysm was successfully treated by antibiotic therapy alone. To the authors' knowledge, de novo aneurysm on the PCA has rarely been reported.

An in vitro study of silk stent morphology.

INTRODUCTION: Morphology of the Silk stent (Balt, Montmorency, France) after deployment is not fully understood, especially in tortuous vessels. An in vitro study was conducted to study morphology and flow-diverting parameters of this stent. METHODS: Two sets of different-sized and curved polytetrafluoroethylene tubes were studied. To simulate the aneurysm neck, a small hole was created in a tube. A stent was placed in each of the different tubes. Angiographic computerized tomography and macroscopic photography were then obtained. The images were analyzed to calculate a Percentage of Area Coverage (PAC). RESULTS: Good stent conformability was observed. The PAC was 21% in the straight model with matched stent and vessel diameter. In the straight model with an oversized stent, the PAC was increased. In the curved models, dynamic wire repositioning occurred. The repositioning was affected by the size of the stent and the angle of the vessel curve. Compared to the straight model, this increased the PAC in two instances: on the convexity (oversized stent), and on the concavity (matched stent and vessel diameter). The PAC did not significantly change at the sides of the curve. CONCLUSIONS: By design, the wires of the silk stent move relative to each other. In a curved model, the PAC is different at the convexity, concavity, and lateral walls. The stent diameter affects the PAC. These results are clinically relevant because it is desirable to maximize and minimize the PAC across the aneurysm neck and branch vessel orifice, respectively.

A study of the first-generation pipeline embolization device morphology using intraoperative angiographic computed tomography (ACT).

INTRODUCTION: The pipeline embolization device (PED, Chestnut Medical, Menlo Park, CA, USA) has been used in our department since September 2008. The first-generation PED had limited radio-opacity. Before September 2008, we began obtaining an angiographic computed tomography (ACT) before and after each procedure to detect intracranial complications. We retrospectively examined the ACT of our patient's with the PED to evaluate the in vivo stent morphology. METHODS: Twelve patients had a PED placed in our department from September 2008 to January 2009. The stent morphology (stent profile and wall apposition) of three segments of each stent was evaluated. RESULTS: Metal coils adjacent to the stent created too much artifact to evaluate the stent morphology in 4 of 12 patients. Two of the 12 patients were excluded for other reasons. Post-processing of the ACT images was necessary to optimize the evaluation of the stent morphology. Six intracranial PEDs could be adequately evaluated by the ACT, and for these particular cases, 18 of 18 stent segments showed an optimal stent profile and 14 of 18 stent segments showed optimal arterial wall apposition. CONCLUSION: ACT provided detailed images of the morphology of the PED in six patients. ACT helped detect two stent segments that required balloon dilation to improve the stent-arterial wall apposition; and during the retrospective analysis (after refining post-processing techniques), we identified one additional stent with suboptimal arterial wall apposition. The main limitation of the ACT was the additional radiation dose to the patient.

Dural arteriovenous fistulas draining into the petrosal vein or bridging vein of the medulla: possible homologs of spinal dural arteriovenous fistulas. Clinical article.

OBJECT: Dural arteriovenous fistulas (DAVFs) with leptomeningeal venous reflux generally pose a high risk of aggressive manifestations including hemorrhage. Among DAVFs, there is a peculiar type that demonstrates direct drainage into the bridging vein rather than the dural venous sinus. The purpose of this study was to investigate the characteristics of DAVFs that drain directly into the petrosal vein or the bridging vein of the medulla oblongata. METHODS: Eleven consecutive cases of DAVFs that drained directly into the petrosal vein and 6 that drained directly into the bridging vein of the medulla were retrospectively reviewed. These cases were evaluated and/or treated at Hospital de Bicêtre in Paris, France, over a 27-year period. A review of previously reported cases was also performed. RESULTS: Both of these "extrasinusal"-type DAVFs demonstrated very similar characteristics. There was a significant male predominance (p < 0.001) for this lesion, and a significantly higher incidence of aggressive neurological manifestations including hemorrhage or venous hypertension than in DAVFs of the transverse-sigmoid or cavernous sinus (p < 0.001). This finding was considered to be attributable to leptomeningeal venous reflux. Regarding treatment, endovascular embolization (either transarterial or transvenous) is frequently difficult, and surgery may be an effective therapeutic choice in many instances. CONCLUSIONS: Embryologically, both the petrosal vein and the bridging vein of the medulla are cranial homologs of the spinal cord emissary bridging veins that drain the pial venous network. The authors believe that DAVFs in these locations may be included in a single category with spinal DAVFs because of their similar clinical characteristics.

Pathomechanisms of symptomatic developmental venous anomalies.

BACKGROUND AND PURPOSE: Although it is generally accepted that developmental venous anomalies (DVAs) are benign vascular malformations, over the past years, we have seen patients with symptomatic DVAs. Therefore, we performed a retrospective study and a literature study to review how, when, and why DVAs can become clinically significant. METHODS: Charts and angiographic films of 17 patients with DVAs whose 18 vascular symptoms could be attributed to a DVA were selected from a neurovascular databank of our hospital. MRI had to be available to rule out any other associated disease. In the literature, 51 cases of well-documented symptomatic DVAs were found. Pathomechanisms were divided into mechanical and flow-related causes. RESULTS: Mechanical (obstructive or compressive) pathomechanisms accounted for 14 of 69 symptomatic patients resulting in hydrocephalus or nerve compression syndromes. Flow-related pathomechanisms (49 of 69 patients) could be subdivided into complications resulting from an increase of flow into the DVA (owing to an arteriovenous shunt using the DVA as the drainage route; n=19) or a decrease of outflow (n=26) or a remote shunt with increased venous pressure (n=4) leading to symptoms of venous congestion. In 6 cases, no specific pathomechanisms were detected. CONCLUSIONS: Although DVAs should be considered benign, under rare circumstances, they can be symptomatic. DVAs, as extreme variations of normal venous drainage, may represent a more fragile venous drainage system that can be more easily affected by in- and outflow alterations. The integrity of the DVA needs to be preserved irrespective of the treatment that should be tailored to the specific pathomechanism.