Endovascular treatment of hemifacial spasm associated with a petrosal DAVF using transarterial Onyx embolization. A case report

Microsurgical treatment for superior petrosal sinus dural arteriovenous fistulas

Superior petrosal sinus (SPS) dural arteriovenous fistulas (DAVFs) are a commonly encountered type of tentorial DAVF that occasionally requires microsurgical intervention. This study aims to analyze the tributaries of the superior petrosal vein (SPV) observed intraoperatively, their association with clinical symptoms, and venous drainage patterns. This retrospective study reviewed 34 consecutive patients with SPS DAVFs who underwent microsurgical treatment at a single institution between 2014 and 2022. The cohort had a mean age of 52.8 ± 11.8 years, with 85.3% (29/34) being male. Predominant symptoms included venous hypertensive myelopathy (VHM) (55.9%) and intraparenchymal or subarachnoid hemorrhage (23.5%). Standard retrosigmoid approach was used to ligate 94.1% (32/34) of the lesions, resulting in immediate complete fistula occlusion for all patients. Supratentorial venous drainage patterns were associated with a higher incidence of intracranial hemorrhage and venous varix (P = 0.047). Infratentorial drainage patterns were more frequently linked with VHM-related symptoms (P<0.001). Patients presenting VHM-related symptoms showed a higher prevalence of drainage through the vein of the cerebellopontine fissure (VCPF) (P = 0.01), while those with intracranial hemorrhage symptoms exhibited a higher prevalence of pontotrigeminal vein (PTV) drainage (P = 0.033) in their DAVFs. Endovascular management of SPS DAVFs carries inherent risks. Surgical treatment via standard retrosigmoid craniotomy offers favorable clinical outcomes with high rates of cure. In cases featuring infratentorial venous drainage, the predominant arterialized tributary of the SPV was the VCPF, commonly associated with VHM-related symptoms. Conversely, in cases with supratentorial venous drainage, the predominant arterialized SPV tributary was the PTV, often associated with intracranial hemorrhage symptoms.

Benchtop and in Vitro Experiments of Novel Transform Stents for Trigeminal Neuralgia Treatment

BACKGROUND

Trigeminal neuralgia (TN) is a debilitating condition characterized by sudden, excruciating facial pain due to neurovascular compression of the trigeminal nerve. Stent deployment can change the course of the superior cerebellar artery upwards, possibly releasing the root entry zone of the trigeminal nerve. We developed a novel stent, the Transform stent, for TN treatment, and evaluated its mechanical properties using benchtop and in vitro hemocompatibility tests.

METHODS

We compared the performance of Transform and Enterprise stents in treating TN because they share similar self-expanding closed-cell features in the manufacturing process, are derived from nitinol tubes, and are fabricated through a laser-cutting process, but also because only the safety of Enterprise stents deployed in intracranial arteries has been reported clinically. All benchtop measurements, including radial force, trackability, bending stiffness, and conformability, were performed thrice for each stent model, and their average values are presented.

RESULTS

Transform stents showed higher radial forces in vessels of diameters ranging from 1.0 mm than Enterprise stents. The trackability of the Transform stent was better than that of the Enterprise stent in a neurovascular model. Bending stiffness was stronger in the Transform stent whereas conformability was superior in the Enterprise stent. No significant thrombogenic issues were observed in the in vitro hemocompatibility tests.

CONCLUSIONS

This study demonstrated the Transform stent as a potential option and paved the way for innovative endovascular approaches for the future TN treatment. Namely, the study confirmed that the characteristics of Transform stents at benchtop and in vitro evaluations may be used as a first step for studies such as in vivo pre- and clinical studies.

Dural arteriovenous fistula involving superior petrosal sinus with petrosal venous drainage in association with cerebral venous thrombosis: Literature review and illustrative case

Background

Dural arteriovenous fistulas (DAVFs) involving superior petrosal sinus (SPS) and superior petrosal vein (SPV) are extremely rare. The pathogenesis of these fistulas remains unclear. We are illustrating 2 cases of DAVFs involving the superior petrosal sinus and veins associated with venous sinus thrombosis with a literature review.

Methods

We reviewed the literature using the PRISMA (preferred reporting items for systematic reviews and meta-analyses) guidelines focusing on DAVFs involving the SPS and/or SPV. Additionally, we searched for additional articles through the reference lists of the included studies.

Results

Our review yielded 20 articles from 1997 until 2022 involving 33 patients with 34 fistulas, including our 2 patients. The mean age was 55.1 ± 12.9 years (range 25-85), 54.5% were males (n = 18). The patients presented with hemorrhage in 36.4% (n = 12), and progressive myelopathy in 30.3% (n = 10). Most fistulas often had arterial supply from MMA, MHT, and/or OA. The fistulas had infratentorial drainage in 64.71% (n = 22), supratentorial drainage in 23.53% (n = 8), and both supra and infratentorial drainage in 11.76% (n = 4). In 27.3% (n = 9), cerebral venous thrombosis was mentioned or identified. Endovascular treatment was performed in 47.1% of cases (n = 16), surgery in 29.4% (n = 10), and combination of treatments in 23.5% (n = 8). A total of 30.3% (n = 10) of cases had incomplete recovery or poor result.

Conclusion

DAVFs involving the SPS and/or SPV are associated with aggressive natural history, requiring early diagnosis and prompt treatment, leading to good prognosis. These fistulas may be acquired in origin, probably secondary to cerebral venous thrombosis.

Diagnosis and Treatment of a Dural Arteriovenous Fistula Involving the Superior Petrosal Vein

OBJECTIVE

A dural arteriovenous fistula involving the superior petrosal vein (SPV DAVF) is an extremely rare condition. Therefore, its clinical presentation, imaging characteristics, treatment methods, and risk factors remain unclear. In this study, we discuss and analyze the aforementioned features of an SPV DAVF.

METHODS

We retrospectively reviewed 30 patients with SPV DAVFs, with a 1-year follow-up rate of 96.67% (29 of 30). The neurological function of the patients was assessed using the modified Aminoff-Logue scale and the modified Rankin Scale score. The risk factors before and after treatment were established using univariate and multivariate logistic regression analyses. Additionally, treatments involving 3 distinct SPV DAVF drainage patterns were presented.

RESULTS

Of the 30 patients, 24 were men (80.0%). Besides, the angiography images were reexamined 12 months after surgery. Univariate analyses indicated that the extent of edema (odds ratio 1.889, 95% confidence interval 1.132-3.154) and the number of draining veins (≤2) (odds ratio 10.833, 95% confidence interval 1.961-59.834) were risk factors for pretreatment modified Rankin Scale score ≥3. However, multivariate analyses revealed no statistically significant differences (P = 0.051, P = 0.055). Following the multivariate analyses, steroid pulse (odds ratio 12.153 95% confidence interval 1.080-136.772) was found to be the only significant risk factor for post-treatment difference between pretreatment and 1-year follow-up modified Rankin Scale score ≥2.

CONCLUSIONS

A DAVF with SPV drainage is an uncommon type of intracranial vascular malformation. Most lesions involve the brain stem or high cervical spinal cord, thereby posing a higher risk of disability or death. Moreover, neuronal damage from persistent venous hypertension is permanent. Therefore, precise diagnosis and timely treatment are key to a good patient prognosis.

Endovascular Treatment of Hemifacial Spasm Associated with a Tentorial DAVF Using Transarterial Onyx Embolization: A Case Report

Objective

We describe a patient treated with transarterial Onyx embolization for a tentorial dural arteriovenous fistula (DAVF) who presented with hemifacial spasm (HFS).

Case Presentation

A 56-year-old man suffered from right blepharospasm for 4 years, and the symptom gradually spread to the right side of his face with oculo-oral synkinesis. MRI of the brain revealed abnormal multiple flow voids at the surface of brainstem and cerebellar hemisphere. MRA (time of flight) and spoiled gradient recalled echo-revealed abnormal vessels at the posterior fossa indicated arteriovenous shunting. 3D-MRI fusion images showed that a dilated vein was in contact with the root exit zone (REZ) of the right facial nerve. The right carotid angiography displayed a complex tentorial DAVF on the right side. There were multiple feeding vessels drained to the tentorial sinus at the point where the inferior cerebellar vermian vein met, and severe venous congestion was noted. We diagnosed a tentorial DAVF and thought that this was responsible for the right HFS. We used neuroendovascular treatment for this lesion. After transarterial Onyx embolization, his right HFS diminished. MRI after treatment showed that the vein in contact with the REZ of the right facial nerve had shrank.

Conclusion

We experienced a rare case of HFS associated with a DAVF. Our case supports that transarterial Onyx embolization can treat HFS associated with a tentorial DAVF. It is the first description of successful treatment that could be confirmed through postoperative MRI.

Coil Embolization of VA-PICA Aneurysm Presenting with Hemifacial Spasm with Assistance of Abnormal Muscle Response Monitoring

Objective

We report a rare case of symptomatic vertebral and posterior inferior cerebellar arteries (VA-PICA) aneurysm-caused ipsilateral hemifacial spasm (HFS) for which coil embolization of the aneurysm with the assistance of abnormal muscle response (AMR) monitoring was effective.

Case Presentation

A 62-year-old woman presented with left HFS. Magnetic resonance imaging showed a saccular aneurysm of the left VA-PICA which compressed the seventh cranial nerve at its root exit zone (REZ). Stent-assisted coil embolization resulted in intraoperative disappearance of AMR in the intraoperative electrophysiological study and HFS was relieved temporally. One month after endovascular surgery, HFS slightly occurred again with the re-appearance of the AMR, although there was no recurrence of aneurysm. Thereafter, the frequency of her HFS markedly decreased to once per several days 1 year after the coiling.

Conclusion

Although complete disappearance of symptoms was not obtained, it was suggested that coil embolization is one of the therapeutic options for HFS which is caused by aneurysmal compression of REZ and intraoperative AMR is useful for identification of responsible lesions and determination of therapeutic effects.

Remission of neurovascular conflicts in the cerebellopontine angle in interventional neuroradiology

Background and purpose

To investigate the efficacy of endovascular treatment (EVT) for neurovascular conflicts (NVCs) in the cerebellopontine angle (CPA) caused by intracranial aneurysms (IAs) and intracranial arteriovenous malformations (AVMs), including trigeminal neuralgia, hemifacial spasm, and glossopharyngeal neuralgia.

Materials and methods

From January 2010 to January 2014, 14 consecutive patients presenting with three NVCs caused by IAs or intracranial AVMs were admitted to our department. The clinical outcomes of these NVCs after EVT were retrospectively analyzed.

Results

For four patients with IAs, angiographic follow-up confirmed total occlusion of the lesion in all, and the clinical outcomes of NVC were as follows: gradual relief in two (50%), transient partial relief but recurrence in one (25%), and no palliative effect in one (25%). For the 10 patients with intracranial AVMs, one (10%) experienced transient relief of NVC after angiogram examination (no EVT was performed). Of the other nine patients who received EVT, angiographic follow-up was obtained in seven (70%), demonstrating total obliteration of the lesion in three (30%), subtotal obliteration in two (20%), and partial obliteration in two (20%). Clinical outcomes included immediate relief of NVCs after single EVT in two cases (20%), gradual relief after single EVT in five (50%, one of them experienced transient aggravation), and complete relief after two sessions of EVT in two (20%). Complications of transient cranial nerve paresis related to EVT occurred in two cases (20%) with intracranial AVMs. In all, complete lasting relief of the NVCs was obtained finally in 11 cases (78.6%).

Conclusions

EVT is a feasible and less invasive approach for relief of NVCs in the CPA caused by IA or intracranial AVM and could be considered as a therapeutic option in these situations.