Carotid Cavernous Fistula Treatment via Flow Diversion: A Systematic Review of the Literature

Stand-alone transarterial flow diversion for treatment of carotid cavernous fistulas

OBJECTIVE

Carotid-cavernous fistulas (CCFs) are rare arteriovenous communications allowing blood to flow from the carotid artery into the cavernous sinus. Although currently coil and/or liquid embolization remain the preferred treatment methods for CCFs, flow diverters (FD) stents represent a viable alternative to traditional embolization techniques. This study explores both the technical aspects and rationale behind using FD stents as a stand-alone treatment approach for CCFs.

METHODS

The study includes records of 7 patients with CCFs treated at two comprehensive stroke centers from 2019 to 2023. Patients treated with FD stenting in conjunction with coil and/or liquid embolization were excluded from the study.

RESULTS

Five patients were diagnosed with direct CCFs and 2 patients with indirect CCFs. Six patients were treated with the Surpass Evolve FD stent and 1 patient with the Pipeline FD stent. DSA follow-up was performed for an average duration of 14.4 months following FD placement. Complete fistula obliteration with no residual shunting was observed in all patients. Furthermore, all patients experienced a complete resolution of symptoms following treatment.

CONCLUSIONS

The authors' experiences suggest the efficacy and safety of FD stenting as a stand-alone treatment option for CCFs. Compared to embolization, FD stents can better preserve the parent vessel and promote healing with less associated mass effect. Despite being a retrospective self-assessment with a relatively small sample size, to the authors' knowledge, this study represents the largest individual case series of patients with CCF treated with stand-alone FD stenting.

Spontaneous thrombosis of post-traumatic direct carotid-cavernous fistula

Carotid cavernous fistula (CCF) is an abnormal communication between the carotid artery and the cavernous sinus, which is most commonly caused by trauma. Due to its high-flow nature and aggressive clinical course, spontaneous resolution of CCF is rare, making endovascular embolization necessary. This procedure aims to prevent potential vision loss, emphasizing the importance of timely intervention to preserve visual function. We report a case of Barrow type A carotid-cavernous fistula which resolved spontaneously. A 42-year-old male was referred to Emergency Room with a chief complaint of seizure 3 days before admission. The seizure was both arm stiff and jerking, the eyes gazing upward, bitten tongue, foamy mouth, no bed wetting. Meanwhile, the patient was unconscious during and after the seizure. Regarding the medical history, the patient experienced head trauma 8 months ago due to a traffic accident. Additionally, the patient reported symptoms of redness, swelling, double vision, and inability to look to the right eye. Initial cerebral angiography was performed, reporting a carotid-cavernous fistula of Barrow type A. Further endovascular treatment could not be carried out, but a second cerebral angiography was conducted after a year, demonstrating spontaneous thrombosis of the carotid-cavernous fistula of Barrow type A. CCF were classified by Barrow et al. into types A, B, C, and D. It has been proposed that spontaneous resolution of CCF Barrow type A may result from thrombosis of the cavernous sinus.

Cavernous Sinus Syndrome in a Polio-Afflicted Patient With Multiple Aneurysms

Cavernous sinus syndrome (CSS) is a complex, multifactorial condition that presents with a myriad of signs and symptoms including ptosis, double vision, and headache. We present the case of a 65-year-old woman with a chief concern of left-eye pain, including polio syndrome and hip replacement surgery. Unlike typical CSS cases often linked to tumors, this patient's condition involved a carotid-cavernous fistula (CCF), multiple internal carotid artery aneurysms, and a pericallosal aneurysm, without any associated tumor. She presented with severe left eye pain, ptosis, double vision, vomiting, headache, and other neurological symptoms since she woke up. Her treatment at a tertiary care center included diagnostic imaging, a cerebral angiogram, and embolization procedures, and she was discharged in stable condition. This case adds significant value to the medical literature by documenting the successful management of CSS with multiple aneurysms and a CCF, highlighting the importance of personalized treatment strategies and the effectiveness of modern embolization techniques in complex neurological conditions.

Natural course of partially embolized carotid-cavernous fistulas

BACKGROUND AND PURPOSE

To present the first study analyzing the clinical and radiological course of carotid-cavernous fistulas (CCFs) following incomplete embolization. The study compares magnetic resonance angiography (MRA) to plain angiography (digital subtraction angiography [DSA]) and investigates the long-term ophthalmological impact of residual fistula.

METHODS

Fistulas classified as partially embolized after the last endovascular treatment were prospectively followed with DSA, MRA, and ophthalmological examination. Both direct and indirect CCFs were included.

RESULTS

Twenty-one CCFs were included in the study. Nine (43%) fistulas were direct and 12 (57%) were indirect. A favorable clinical outcome of modified Rankin scale ≤2 was recorded in 19 (90%) patients at the last follow-up. Postinterventional ophthalmologic examinations in 16 patients revealed no negative effects of residual fistulas; five remaining patients refused to undergo further examination. Spontaneous thrombosis and complete occlusion of the CCF were demonstrated in 90% of patients, with a mean time to occlusion of 5.7 ± 4.7 months. Fourteen (66%) patients completed the full imaging follow-up (MRA and DSA). In 21% of these cases, discrepancy between the two imaging modalities was observed-MRA failed to detect persistent fistulas identified by DSA.

CONCLUSIONS

The goal of CCF treatment is safe and complete embolization. However, if adequate flow reduction is achieved, both direct and indirect CCFs tend to spontaneously thrombose. Residual flow does not result in ophthalmological deterioration until the fistula is completely closed. MRA may not be sufficiently sensitive to detect residues of fistulas including cortical venous drainage. Therefore, complete CCF closure should be confirmed through DSA.

Endovascular treatment of direct carotid cavernous fistula resulting from rupture of intracavernous carotid aneurysm: A case report

BACKGROUND

Direct carotid cavernous fistulas (CCFs) are typically the result of a severe traumatic brain injury. High-flow arteriovenous shunts secondary to rupture of an intracavernous aneurysm, resulting in direct CCFs, are rare. The use of a pipeline embolization device in conjunction with coils and Onyx glue for treatment of direct high-flow CCF resulting from ruptured cavernous carotid artery aneurysm in a clinical setting is not well documented.

CASE SUMMARY

A 58-year-old woman presented to our department with symptoms of blepharoptosis and intracranial bruits for 1 wk. During physical examination, there was right eye exophthalmos and ocular motor palsy. The rest of the neurological examination was clear. Notably, the patient had no history of head injury. The patient was treated with a pipeline embolization device in the ipsilateral internal carotid artery across the fistula. Coils and Onyx were placed through the femoral venous route, followed by placement of the pipeline embolization device with assistance from a balloon-coiling technique. No intraoperative or perioperative complications occurred. Preoperative symptoms of bulbar hyperemia and bruits subsided immediately after the operation.

CONCLUSION

Pipeline embolization device in conjunction with coiling and Onyx may be a safe and effective approach for direct CCFs.

Indications for alternative endovascular techniques in carotid-cavernous fistulas: A 20-year single-center experience

BACKGROUND

While coiling is considered the standard treatment for carotid-cavernous fistulas (CCFs), studies demonstrating excellent results using new materials, especially flow diverter (FD) stents and liquid embolisates, are becoming more frequent. The indications and effectiveness of these alternative endovascular techniques remain unclear.

METHODS

A total of 22 direct and 20 indirect CCFs were included in the study. These were further subdivided based on the embolic material used: coils versus FD stents for direct and coils versus liquid embolisates for indirect CCFs. The subgroups were subjected to statistical analysis.

RESULTS

An angiographic cure was achieved in 88% of all CCFs, 93% of patients' experienced clinical improvement or remained stable. Direct CCFs were treated with coiling (41%) or with both coils and FD stents (55%). One (4%) patient with a direct CCF was treated with FD stent alone. Statistical analysis comparing these subgroups revealed a significantly higher complete occlusion rate immediately after treatment in the coiling subgroup (67% vs. 23%, p = 0.0409). The occlusion rates at the last follow-up were similar (89% vs. 85%). Indirect CCFs were treated with coiling (35%) or liquid embolisates (65%). All three periprocedural ischemic complications were recorded within the liquid subgroup, resulting in a significantly higher clinical deterioration rate (p = 0.0333).

CONCLUSION

FD stents in direct and liquid embolisates in indirect fistulas did not demonstrate better angiographic or clinical outcomes compared to convetional coiling. Liquid agents carried a higher risk of ischemic complications. Alternative embolization materials should be reserved for CCFs that cannot be treated with simple coiling.

Venous outflow-targeted coil embolization of direct carotid-cavernous fistulas

BACKGROUND

Coil embolization is the mainstay treatment for carotid-cavernous fistulas (CCFs). However, few studies have reported entire occlusion of engorged veins to interrupt venous outflow. We report our experience with venous outflow-targeted coil embolization of direct CCFs.

METHODS

We retrospectively reviewed all the patients diagnosed with direct CCFs treated with venous outflow-targeted coil embolization between November 2013 and February 2020. Venous outflow-targeted coil embolization of the CCFs was performed as follows. First, transarterial stent-assisted coil embolization of CCFs was performed. If the venous outflow to the engorged veins persisted after transarterial stent-assisted coil embolization, entire occlusion of the engorged veins and additional coil packing within the cavernous sinus were performed to interrupt the venous outflow.

RESULTS

Ten patients had undergone venous outflow-targeted coil embolization, 6 women (60%) and 4 men (40%). Transfemoral cerebral angiography showed high-flow, direct CCFs in all the patients. Venous outflow occurred through the superior ophthalmic vein (SOV) in all the patients and was completely interrupted by the entire occlusion of the engorged veins with fibered coils. Three patients (30%) had undergone additional treatment in a supplementary manner because of recurrent symptoms (chemosis in 1 patient, faint tinnitus in 2 patients) in the early postprocedural period (1 to 4 weeks). All the symptoms were resolved on follow-up. No additional recurrence was found during follow-up (1-75 months). No peri-procedural complications were encountered.

CONCLUSIONS

Venous outflow-targeted coil embolization of CCFs would be a safe and effective treatment method.

Outcomes After Endovascular Treatment of Direct Carotid Cavernous Fistulas: Systematic Review and Meta-Analysis

BACKGROUND

Direct carotid cavernous fistulas (dCCF) involve pathologic shunting from the internal carotid artery into the cavernous sinus. We systematically reviewed the methods and outcomes of endovascular therapy for dCCF.

METHODS

PubMed, Scopus, and EMBASE were used to identify studies that reported outcomes for patients undergoing embolization of dCCF. Outcomes included rates of occlusion, complications, symptom improvement, and recurrence. Pooled rates for each outcome were obtained with random effects models. The influence of embolization method on outcomes was assessed with meta-regressions.

RESULTS

There were 16 studies comprising 270 patients. The mean age was 39.6 years, there were 36.3% females, and the mean follow-up was 19.7 months. Coils were the most common method of embolization (69.3%), followed by Onyx (31.1%), covered stent (22.2%), N-butyl cyanoacrylate (6.7%), and flow diversion (4.8%). The pooled overall occlusion rate was 92.1% (95% confidence interval [CI], 86.3-95.6; I2 = 29.2%). The pooled complication rate was 10.9% (95% CI, 7.3-16; I2 = 0%). Use of coils were associated with a slightly lower odds of overall complications (odds ratio, 0.98; 95% CI, 0.97-0.99) and cranial nerve palsy (odds ratio, 0.98; 95% CI, 0.97-0.99). The pooled fistula recurrence rate was 8.3% (95% CI, 4.3-15.4; I2 = 30.9%).

CONCLUSIONS

Endovascular therapy for dCCF is associated with high occlusion and low complication rates. Recurrence is not uncommon, highlighting the need for close follow-up.

Direct puncture the superior ophthalmic vein guiding by Dyna-CT to obliterating a traumatic carotid-cavernous sinus fistula: A case report and literature review

RATIONALE

Traumatic carotid-cavernous sinus fistula (TCCF) is a pathological shunt between the carotid arteries and cavernous sinus due to trauma. Imaging-guided (e.g., ultrasonic image and fluoroscopic roadmap image) direct puncture of the superior ophthalmic vein (SOV) for embolization of TCCF has been previously described in other studies.

PATIENT CONCERNS AND DIAGNOSIS

We report a case of TCCF in a 58-years-old male patient who was admitted to our hospital with a sustained head injury after falling from a high platform, resulting in rapidly progressive swelling, pain, diminishing vision for more than 6 months, and blindness in his left eye for 1 month.

INTERVENTIONS AND OUTCOMES

The patient underwent digital subtraction angiography and endovascular embolization. After the failure of super-selection of the left cavernous sinus, an alternative approach to obliterating the TCCF by puncturing the SOV is directly guided by Dyna-CT. After embolization, the patient's clinical symptoms gradually disappeared and discharged from the hospital 5 days later. No recurrence or complications occurred during follow-up for 1 year.

CONCLUSION

This case illustrates that direct puncture of the SOV guided by Dyna-CT as an alternative approach to embolization of TCCF is safe, effective, and feasible.

Balloon-Assisted Roadmap Technique to Enable Flow Diversion of a High-Flow Direct Carotid-Cavernous Fistula

BACKGROUND

The use of flow diverters as a first-line treatment for direct carotid cavernous fistula (CCF) is a relatively new approach in the neurointerventional field which allows obliteration of the fistula with less mass effect from coils in the cavernous sinus. Safe and successful deployment of a flow diverter requires adequate imaging of the parent vessel, which may be challenging in the setting of high-flow CCF without antegrade flow.

OBJECTIVE

To facilitate adequate parent vessel imaging in the setting of high-flow CCF to enable the safe development of a flow diverter device.

METHODS

Here we present the case of a patient with delayed presentation of post-traumatic direct CCF after a motor vehicle accident, with no antegrade flow past the fistulous connection. We used temporary balloon occlusion of the fistulous connection to enable road-map imaging of the parent vessel and flow-diverter placement. "Drag and drop" device opening in the middle cerebral artery facilitated better deployment of the flow-diverter against retrograde cavernous flow through the fistula.

RESULTS

Temporary balloon occlusion of the fistulous connection was used to acquire a roadmap to facilitate safe deployment of a flow diverter and subsequent treatment of the CCF with transvenous coil embolization, with complete resolution of symptoms.

CONCLUSION

Balloon-assisted roadmap use is a novel means of visualizing the parent vessel in direct CCF to facilitate safe flow diverter deployment.