The Visualization Methods of Occluded Dural Sinus for Safe Transvenous Embolization of Dural AVFs

Transvenous Embolization for Isolated Superior Petrosal Sinus Dural Arteriovenous Fistula

Isolated superior petrosal sinus dural arteriovenous fistula (SPSdAVF) is a rare condition for which transvenous embolization is a safe treatment, even if accessing the isolated sinus can be challenging. A 39-year-old female patient with dizziness and right facial palsy underwent magnetic resonance imaging, revealing a venous infarction at the posterior fossa and a dural arteriovenous fistula. Digital subtraction angiography showed an isolated SPSdAVF. The shunt point was posterior to the isolated superior petrosal sinus, and the shunt flowed only through the petrosal vein. Contrast-enhanced magnetic resonance imaging showed thrombosis at the anterior segment of the superior petrosal sinus. Transvenous embolization was successfully performed via the thrombosed anterior segment of the superior petrosal sinus without associated complications. This case shows that transvenous embolization through a thrombosed superior petrosal sinus is an alternative treatment option for isolated SPSdAVF.

Transvenous embolization along with intraprocedural image fusion technique for complex intracranial dural arteriovenous fistula

PURPOSE

This study aimed to investigate the efficacy and safety of an intraprocedural image fusion technique using flat-panel detector computed tomography-based rotational angiography (FDCT-RA) and image fusion (IF) for the transvenous approach in treating intracranial dural arteriovenous fistulas (dAVFs).

METHODS

A retrospective review was conducted on patients who underwent transvenous embolization for dural AVFs. The patients were classified into two groups according to the treatment technique used: the FDCT-RA and IF technique group and the conventional technique group. The primary outcomes assessed were the angiographic and clinical outcomes, complications, fluoroscopy time, and radiation exposure. Univariate analyses were performed to compare the two treatment modalities.

RESULTS

Eighty-six patients with intracranial dAVFs were treated with transvenous embolization (TVE), of which 37 patients underwent transvenous approach with flat-panel detector computed tomography-based rotational angiography (FDCT-RA) and image fusion (IF) technique used. The FDCT-RA and IF group showed difference in the location of dAVFs, occlusion state of the sinus, and access routes in comparison to the conventional treatment group. The FDCT-RA and IF technique was predominantly used for dAVFs involving the anterior condylar confluence and cavernous sinus with ipsilateral inferior petrosal sinus (IPS) occlusion. Patients treated with this technique demonstrated a higher rate of complete occlusion (91.9%, n = 34) compared to those treated with the conventional technique (79.6%, n = 39), but this difference was not statistically significant (p = 0.136). Although the implementation of this technique during the treatment procedure showed a tendency to decrease both fluoroscopy duration and radiation dose, the observed results did not reach statistical significance (p = 0.315, p = 0.130).

CONCLUSION

The intraprocedural image fusion technique using FDCT-RA for transvenous treatment of intracranial dAVFs could provide help in treatment of dAVFs of certain locations or access routes. It might provide aid in microcatheter navigation, without increasing the radiation exposure and fluoroscopy time.

Contrast-Enhanced Magnetic Resonance Imaging Suggested a Possibility of Transvenous Embolization in the Superior Petrosal Sinus Dural Arteriovenous Fistula: A Case Report

Objective

Superior petrosal sinus dural arteriovenous fistula (SPS-DAVF) is a rare subtype of intracranial DAVF that sometimes leads to hemorrhagic symptoms following deep venous drainage. Here we report the case of SPS-DAVF with retrograde venous reflux to the cerebellar vein. Preoperative contrast-enhanced MRI was a decisive factor in a safe and effective treatment.

Case Presentation

A 37-year-old woman was referred to our hospital with abnormal MRI findings, which was performed when she had a mild headache during her check-up. DSA revealed left-sided SPS-DAVF, which was diagnosed as Cognard type IIb. Both CTA and DSA could not detect the whole SPS but only the shunt pouch. Using contrast-enhanced MRI, we were able to visualize the presence of the SPS and its continuity within the shunt pouch. 3D-T1 turbo spin echo (SPACE) showed a low-intensity area in the SPS, which was not seen in the 3D-T1 fast field echo (FFE). During the procedure, there was a point where it was difficult to advance the microcatheter, which coincided with the low-intensity area. We achieved effective transvenous embolization from the occluded venous access by devising a surgical technique.

Conclusion

In addition to the contrast-enhanced 3D-T1 FFE, 3D-T1 SPACE might provide beneficial information for endovascular therapy in the evaluation of venous sinuses, which could not be detected by standard examinations.

Dural Arteriovenous Fistulas in the Parasellar Region Other Than the Cavernous Sinus

Besides cavernous sinus (CS) dural arteriovenous fistulas (AVFs), AVF may develop around the parasellar region. They can cause various symptoms, and some of them may show similar symptoms to those of CS dural AVF. Therefore, these AVFs may be misdiagnosed as CS dural AVFs. In this review, we divided parasellar AVFs into four groups based on their locations related to the CS: anterior group (orbit), anterolateral group (sphenoid wing), posteroinferior group (inferior petrosal sinus and clivus), and posterior group (superior petrosal sinus and petrosal vein). Although parasellar AVFs share common points, there are many differences between the four groups. We herein discuss commonalities and differences in parasellar AVFs based on a review of the literature and our experience.