Stereotactic Radiosurgery for Dural Carotid Cavernous Sinus Fistulas

Open Surgical Obliteration of Three Indirect Carotid-Cavernous Fistulas

BACKGROUND AND IMPORTANCE

Carotid-cavernous fistulas (CCFs) are abnormal connections between the carotid artery and the cavernous sinus (CS). CCFs are primarily treated by an endovascular route, but there are situations in which a lesion is not amenable to endovascular or transorbital treatment, necessitating a transcranial approach. In this select group of patients, the use of crushed temporalis muscle to pack the CS fistula site was found to be an effective method for treatment of CCFs.

CLINICAL PRESENTATION

In this case series, we present 3 patients with CCFs in which endovascular treatment was not possible because of occlusion of the petrosal sinuses or stenosis of the superior ophthalmic vein at the superior orbital fissure, rendering the lesion inaccessible by a transvenous or transorbital route. Each patient was treated with a variation of temporalis muscle packing through a skull base triangle; one was treated through the anteromedial triangle, one through the supratrochlear triangle, and the third through the Parkinson triangle. The fistulas were cured in each case.

CONCLUSION

Cavernous-carotid fistulas that are not amenable to endovascular or transorbital treatment can be successfully treated by packing the CS fistula site with crushed temporalis muscle. To cure these patients' symptoms and enhance their quality of life, it is crucial to weigh the advantages and disadvantages of each therapy option.

Efficacy and safety of stereotactic radiosurgery versus endovascular treatment for symptomatic cavernous sinus dural arteriovenous fistula without ophthalmological emergency: a single-center 10-year experience

OBJECTIVE

Stereotactic radiosurgery (SRS) is emerging as a treatment option for cavernous sinus dural arteriovenous fistula (CS dAVF); it is less invasive and has a lower complication rate than conventional surgeries. However, little is known regarding the advantages and limitations of SRS compared to those of endovascular treatment (EVT). The aim of this study was to compare the efficacy and safety between EVT and SRS for treatment of CS dAVF.

METHODS

Between January 2011 and April 2021, a total of 86 consecutive patients diagnosed with CS dAVF were treated with EVT or SRS. Among them, 8 patients with ophthalmological emergency and 8 without follow-up data at ≥ 12 months were excluded. During the same period, no neurological deficit due to intracranial hemorrhage or seizure was noted in any of the patients. Ultimately, 70 patients (EVT 33, SRS 37) were included in this study. Demographic characteristics, initial clinical presentations, clinical outcomes, and radiological findings were retrospectively reviewed and compared. Procedure-related complications were also assessed after the treatments.

RESULTS

The patients’ baseline characteristics (except conjunctival symptoms) and angiographic features of CS dAVF were not significantly different between the EVT and SRS groups. Conjunctival symptoms were more frequently noted in the EVT than in the SRS group (69.7% vs 40.5%, p = 0.015). After EVT, initial complete obliteration was achieved in 20 cases (60.6%). Complete obliteration was achieved at 6 months in 86.4% of cases with EVT and in 77.8% of those treated with SRS (p = 0.507), and at 12 months in 86.4% cases with EVT and in 94.4% of those treated with SRS (p = 0.357). Worsening of symptoms developed at 1 month in 24.2% of cases with EVT and in 5.4% of those treated with SRS (p = 0.038); at 6 months in 22.6% of cases with EVT and in 10.8% of those treated with SRS; and at 12 months in 30.0% of cases with EVT and in 13.5% of those treated with SRS (p = 0.099). The angioarchitecture of CS dAVF did not affect angiographic obliteration after SRS. Procedure-related morbidity and mortality occurred more frequently in the EVT than in the SRS group (27.3% vs 8.1%, p = 0.034).

CONCLUSIONS

Both EVT and SRS were effective for the treatment of CS dAVF without ophthalmological emergency. However, procedure-related morbidity and mortality was less frequent in SRS than in EVT, and consequently SRS may be more advantageous in terms of safety.

Radiation Exposure During Diagnostic and Therapeutic Angiography of Carotid-cavernous Fistula : A Retrospective Single Center Observational Study

Purpose

The aim of this study was to determine local diagnostic reference levels (DRLs) during endovascular diagnostics and therapy of carotid-cavernous fistulas (CCF).

Methods

In a retrospective study design, DRLs, achievable dose (AD) and mean values were assessed for all patients with CCF undergoing diagnostic angiography (I) or embolization (II). All procedures were performed with the flat-panel angiography system Allura Xper (Philips Healthcare). Interventional procedures were differentiated according to the type of CCF and the type of procedure.

Results

In total, 86 neurointerventional procedures of 48 patients with CCF were executed between February 2010 and July 2021. The following DRLs, AD and mean values could be determined: (I) DRL 215 Gy ∙ cm², AD 169 Gy ∙ cm², mean 165 Gy ∙ cm²; (II) DRL 350 Gy ∙ cm², AD 226 Gy ∙ cm², mean 266 Gy ∙ cm². Dose levels of embolization were significantly higher compared to diagnostic angiography (p < 0.001). No significant dose difference was observed with respect to the type of fistula or the embolization method.

Conclusion

This article reports on diagnostic and therapeutic DRLs in the management of CCF that could serve as a benchmark for the national radiation protection authorities. Differentiation by fistula type or embolization method does not seem to be useful.

Stereotactic Radiosurgery for Cavernous Sinus Versus Noncavernous Sinus Dural Arteriovenous Fistulas: Outcomes and Outcome Predictors

BACKGROUND

Dural arteriovenous fistulas (DAVFs) can be categorized based on location.

OBJECTIVE

To compare stereotactic radiosurgery (SRS) outcomes between cavernous sinus (CS) and non-CS DAVFs and to identify respective outcome predictors.

METHODS

This is a retrospective study of DAVFs treated with SRS between 1988 and 2016 at 10 institutions. Patients' variables, DAVF characters, and SRS parameters were included for analyses. Favorable clinical outcome was defined as angiography-confirmed obliteration without radiological radiation-induced changes (RIC) or post-SRS hemorrhage. Other outcomes were DAVFs obliteration and adverse events (including RIC, symptomatic RIC, and post-SRS hemorrhage).

RESULTS

The overall study cohort comprised 131 patients, including 20 patients with CS DAVFs (15%) and 111 patients with non-CS DAVFs (85%). Rates of favorable clinical outcome were comparable between the 2 groups (45% vs 37%, P = .824). Obliteration rate after SRS was higher in the CS DAVFs group, even adjusted for baseline difference (OR = 4.189, P = .044). Predictors of favorable clinical outcome included higher maximum dose (P = .014) for CS DAVFs. Symptomatic improvement was associated with obliteration in non-CS DAVFs (P = .005), but symptoms improved regardless of whether obliteration was confirmed in CS DAVFs. Non-CS DAVFs patients with adverse events after SRS were more likely to be male (P = .020), multiple arterial feeding fistulas (P = .018), and lower maximum dose (P = .041).

CONCLUSION

After SRS, CS DAVFs are more likely to obliterate than non-CS ones. Because these 2 groups have different total predictors for clinical and radiologic outcomes after SRS, they should be considered as different entities.

3D Brain Imaging in Vascular Segmentation of Cerebral Venous Sinuses

The three-dimensional (3D) visualization of dural venous sinuses (DVS) networks is desired by surgical trainers to create a clear mental picture of the neuroanatomical orientation of the complex cerebral anatomy. Our purpose is to document those identified during routine 3D venography created through 3D models using two-dimensional axial images for teaching and learning neuroanatomy. Anatomical data were segmented and extracted from imaging of the DVS of healthy people. The digital data of the extracted anatomical surfaces was then edited and smoothed, resulting in a set of digital 3D models of the superior sagittal, inferior sagittal, transverse, and sigmoid, rectus sinuses, and internal jugular veins. A combination of 3D printing technology and casting processes led to the creation of realistic neuroanatomical models that include high-fidelity reproductions of the neuroanatomical features of DVS. The life-size DVS training models were provided good detail and representation of the spatial distances. Geometrical details between the neighboring of DVS could be easily manipulated and explored from different angles. A graspable, patient-specific, 3D-printed model of DVS geometry could provide an improved understanding of the complex brain anatomy. These models have various benefits such as the ability to adjust properties, to convert two-dimension images of the patient into three-dimension images, to have different color options, and to be economical. Neuroanatomy experts can model such as the reliability and validity of the designed models, enhance patient satisfaction with improved clinical examination, and demonstrate clinical interventions by simulation; thus, they teach neuroanatomy training with effective teaching styles.

Endovascular treatment of the cavernous sinus dural arteriovenous fistula: current status and considerations

A cavernous sinus dural arteriovenous fistula (CS-DAVF) is an abnormal arteriovenous communication involving the dura mater within or near the CS wall. The dural arteries from the internal carotid artery and external carotid artery supply the CS-DAVF, and the superior ophthalmic vein (SOV) and inferior petrous sinus (IPS) are frequent venous drainers. In CS-DAVF cases, high-risk lesions require treatment. Endovascular treatment (EVT) has been the first-line option for CS-DAVFs. To our knowledge, a review of the EVT of CS-DAVFs is lacking. Therefore, in this paper, we review the available literature on this issue. In addition, some illustrative cases are also provided to more concisely expound the EVT of CS-DAVFs. According to the recent literature, transvenous embolization via the IPS is considered the most effective method for EVT of CS-DAVFs. In addition, the transorbital approach is another reasonable choice. Other venous approaches can also be tried. Because of the low cure rate, transarterial embolization for CS-DAVFs is limited to only highly selected patients. In the EVT of CS-DAVFs, various agents have been used, including coil, Onyx, and n-butyl cyanoacrylate, with coil being the preferred one. In addition, when EVT cannot obliterate the CS-DAVF, stereotactic radiotherapy may be considered. In general, despite various complications, EVT is a feasible and effective method to manage CS-DAVFs by way of various access routes and can yield a good prognosis.

Multimodal Management of Carotid-Cavernous Fistulas

BACKGROUND

Techniques for endovascular management of carotid-cavernous fistulas (CCFs) have evolved over the years. Current strategies include transarterial or transvenous approaches and direct puncture or exposure of the cavernous sinus. Rarely, complex CCFs may require multiple approaches or procedures. We describe our experience managing CCFs, reporting on outcomes and technical nuances.

METHODS

A retrospective review of institutional records was conducted to identify consecutive cases of CCF treated between July 2005 and July 2016. Pertinent technical details and outcomes were recorded.

RESULTS

In 44 patients, 51 procedures were performed. There were 13 direct CCFs and 31 indirect CCFs: 13 (30%) type A, 3 (7%) type B, 5 (11%) type C, and 23 (52%) type D. A transarterial approach was selected in 39% of cases (n = 20), resulting in a long-term successful embolization rate of 60% (n = 12). Transvenous methods via the inferior petrosal sinus or superior ophthalmic vein were used in 49% of cases (n = 25), resulting in a long-term obliteration rate of 88% (n = 22). Multimodal management was required in 5 patients, including 1 patient in whom a craniotomy was performed to facilitate coil embolization of the cavernous sinus under direct vision. A 7% complication rate (n = 3) was observed, with significant morbidity in 1 patient.

CONCLUSIONS

CCFs are complex vascular lesions that require facility with various endovascular and surgical approaches. High-flow, direct-type fistulas may harbor a significant risk of recurrence after transarterial embolization. Partial or unsuccessful embolization may necessitate an open surgical approach to the superior ophthalmic vein or cavernous sinus.

Gamma knife radiosurgery as an alternative treatment of Barrow type B carotid cavernous fistulas: A case report

RATIONALE

Barrow type B carotid-cavernous fistulas are dural shunts between the meningeal branches of the internal carotid artery and the cavernous sinus; these types of dural fistulas can produce specific patterns of symptoms based on the pattern of venous drainage.

PATIENT CONCERNS AND DIAGNOSES

A 67-year-old man came to our hospital presenting with acute left orbital pain and double vision in the left eye. The diagnosis was carotid-cavernous fistula fed by the meningohypophyseal trunk and drained to the left superior ophthalmic vein.

INTERVENTIONS AND OUTCOMES

We planned gamma knife radiosurgery for the left cavernous sinus including fistula point as an alternative treatment. The orbital pain disappeared in 2 weeks, and all signs and symptoms in the left eye completely improved within 2 months.

LESSONS

Gamma knife radiosurgery may be an alternative treatment for carotid cavernous fistula. Furthermore, in patients with poor vascular access and no fatal presentation, this may be a reasonable first-line treatment option.

Carotid-cavernous fistula: current concepts in aetiology, investigation, and management

A carotid-cavernous fistula (CCF) is an abnormal communication between arteries and veins within the cavernous sinus and may be classified as either direct or dural. Direct CCFs are characterized by a direct connection between the internal carotid artery (ICA) and the cavernous sinus, whereas dural CCFs result from an indirect connection involving cavernous arterial branches and the cavernous sinus. Direct CCFs frequently are traumatic in origin and also may be caused by rupture of an ICA aneurysm within the cavernous sinus, Ehlers-Danlos syndrome type IV, or iatrogenic intervention. Causes of dural CCFs include hypertension, fibromuscular dysplasia, Ehlers-Danlos type IV, and dissection of the ICA. Evaluation of a suspected CCF often involves non-invasive imaging techniques, including standard tonometry, pneumotonometry, ultrasound, computed tomographic scanning and angiography, and/or magnetic resonance imaging and angiography, but the gold standard for classification and diagnosis remains digital subtraction angiography. When a direct CCF is confirmed, first-line treatment is endovascular intervention, which may be accomplished using detachable balloons, coils, liquid embolic agents, or a combination of these tools. As dural CCFs often resolve spontaneously, low-risk cases may be managed conservatively. When invasive treatment is warranted, endovascular intervention or stereotactic radiosurgery may be performed. Modern endovascular techniques offer the ability to successfully treat CCFs with a low morbidity and virtually no mortality.