Carotid Cavernous Fistula.

Carotid cavernous fistulae (CCFs) are arteriovenous shunts involving the cavernous sinus. CCFs are defined as direct or indirect. Direct CCFs are treated by deconstructive or reconstructive techniques depending on whether the affected internal carotid artery is required to perfuse the ipsilateral cerebral hemisphere, as determined by a balloon test occlusion. Indirect CCFs, or dural fistulae of the cavernous sinus wall, are most often treated with transvenous embolization. Stereotactic radiosurgery is reserved for cases of indirect CCFs that are not completely obliterated by embolization. Overall, cure rates are high with relatively low complication rates.

Evaluating the diagnostic performance of non-contrast magnetic resonance angiography sequences in the pre-procedural comprehensive analysis of direct carotid cavernous fistula.

PURPOSE: Endovascular treatment of direct carotid cavernous fistula (DCCF) requires invasive diagnostic cerebral angiography for diagnosis and planning; however, a less invasive modality like magnetic resonance angiography (MRA) can be useful, especially in high-risk cases. This single-centre study evaluated a newer MR angiography (MRA) sequence, silent MRA and the traditional time of flight (TOF) MRA for pre-procedural treatment planning of DCCF. METHODS: All consecutive DCCF patients who underwent TOF, silent MRA and diagnostic cerebral angiography were included in the study. Angiographic features like rent size, location, draining veins and collateral communicating arteries were analysed and compared between the two MRA sequences, with digital subtraction angiography (DSA) as the gold standard. RESULTS: Fifteen patients were included in the study. TOF MRA exhibited better sensitivity (76.9% vs 69.2%) in identifying the rent location, correctly pinpointing the location in 93.3% compared to 73.3% with silent MRA. Both MRA sequences showed good agreement with DSA for primary sac and rent size. TOF MRA correctly identified 86.2% of 210 total venous structures compared to 96% by silent MRA. Silent MRA demonstrated higher sensitivity (90% vs 76%) and accuracy (87.69 vs 94.36) in visualisation of involved veins compared to TOF MRA. CONCLUSION: Arterial characteristics of DCCF like rent location and rent size were better assessed by TOF MRA. Although both MRA identified venous features, silent MRA correlated better with DSA irrespective of the size and proximity to the site of the fistula. Combining both sequences can evaluate various angioarchitectural features of DCCF useful for therapeutic planning.

Bilateral Low-Flow Type-D Dural Carotid-Cavernous Fistula: Diagnosis and Treatment with 3D Time-of-Flight Magnetic Resonance Angiography.

BACKGROUND Carotid-cavernous fistula (CCF) is a rare, atypical vascular shunt between the carotid arterial system and the venous channels of the cavernous sinus, classified according to the shunt's anatomy, by etiology (resulting from trauma or occurring spontaneously), or by hemodynamic characteristics (such as low- or high-flow fistulas). CASE REPORT A 62-year-old female patient with poorly controlled arterial hypertension presented with bilateral periorbital edema, conjunctival chemosis, ophthalmoplegia, diplopia, and diminished visual acuity. On magnetic resonance angiography (MRA), abnormal arterial flow along the cavernous sinuses was noted, suggestive of bilateral CCF. The diagnosis of indirect dural low-flow CCF (Barrow Type D) was later confirmed by digital subtraction angiography, with feeding arteries from intracavernous internal carotid artery branches, and meningeal branches of the external carotid artery, draining bilaterally to ophthalmic veins, the intracavernous sinus, and the inferior petrosal sinus. The patient was successfully treated with endovascular embolization. At 7-month follow-up, no residual arteriovenous shunting was detected. This case highlights the importance of non-invasive radiological methods for CCF, and presents rarely published radiological findings of bilateral Type-D dural CCFs on 3-dimensional time-of-flight MRA with post-treatment MRA follow-up. CONCLUSIONS Regardless of the patient's history of possible trauma, a patient presenting with bilateral periorbital edema, conjunctival chemosis, ophthalmoplegia, diplopia, and diminished visual acuity should have a spontaneous bilateral CCF investigated to prevent delayed treatment. Experienced neuroradiologists are needed to accurately detect indirect CCF, since this condition often does not demonstrate classic symptoms.

Comparison of the transarterial, transvenous, and superior ophthalmic vein approaches in the treatment of indirect carotid-cavernous fistulas.

OBJECTIVE: Indirect carotid-cavernous fistulas (CCFs) are abnormal arteriovenous shunting lesions with a highly variable clinical presentation that depends on the drainage pattern. Based on venous drainage, treatment can be either transarterial (TA) or transvenous (TV). The aim of this study was to compare the outcomes of indirect CCF embolization via the TA, TV, and direct superior ophthalmic vein (SOV) approaches. METHODS: The authors conducted a retrospective analysis of 74 patients admitted to their institution from 2010 to 2023 with the diagnosis of 77 indirect CCFs as confirmed on digital subtraction angiography. RESULTS: A total of 74 patients with 77 indirect CCFs were included in this study. Embolization was performed via the TA approach in 4 cases, the TV approach in 50 cases, and the SOV in 23 cases. At the end of the procedure, complete occlusion was achieved in 76 (98.7%) cases. The rate of complete occlusion at the end of the procedure and at last radiological follow-up was significantly higher in the SOV and TV cohorts than in the TA cohort. The rate of recurrence was highest in the TA cohort (25% for TA vs 5.3% for TV vs 0% for SOV, p = 0.68). CONCLUSIONS: The rate of immediate complete occlusion was higher in the TV and SOV cohorts than in the TA cohort while the rate of complete occlusion at final follow-up was highest in the SOV cohort. The SOV approach was significantly associated with higher rates of postoperative complications. Indirect CCFs require careful examination of the fistulous point and the venous drainage to provide the most effective patient-tailored approach.

Long-term outcome of endovascular treatment for indirect carotid-cavernous fistulas.

OBJECTIVE: Endovascular treatment (EVT) is the primary approach used to treat indirect carotid-cavernous fistulas (CCFs). In this study, the authors evaluated the immediate and long-term efficacy and safety of different endovascular techniques for indirect CCFs. METHODS: The databases of two endovascular centers were retrospectively reviewed to collect the patients with indirect CCFs treated using endovascular techniques between 2013 and 2023. Demographics, clinical presentation, CCF features, EVT characteristics, and clinical and radiological outcomes were evaluated and analyzed. The analysis was performed to compare the clinical and radiological data between different endovascular approaches and different embolic materials. RESULTS: Ninety-eight patients were included in the study. EVT was successful in 95 patients (96.9%). Immediate complete obliteration of the CCF was achieved in 93.9% of patients, with 98% undergoing embolization with liquid embolic agents (LEAs) and 95.6% undergoing coiling alone. Complete CCF obliteration was higher in the transvenous than in the transarterial approach (94.3% vs 75%, p = 0.010). At ≥ 6 months follow-up, complete CCF obliteration was achieved in all patients (100%). The rate of procedure-related complications was higher following LEAs than with coiling alone (32.0% vs 15.6%). New cranial nerve (CN) palsy was diagnosed in 26.0% and 2.2% after embolization with LEAs and coiling alone, respectively (p = 0.001), with complete CN palsy recovery in 78.6%. Procedure-related intracranial hemorrhage occurred in 3 patients (3.1%). Two patients experienced an ischemic stroke following Onyx migration into the internal carotid artery. Ocular symptoms improved in 93% (83/89) of the patients who were followed. CONCLUSIONS: In this study, complete obliteration of an indirect CCF was achieved in more than 90% of patients. Despite the occurrence of some new postprocedural ocular CN palsy, ocular symptoms improved in most patients in long-term follow-up. The transvenous approach was the most effective method for treating the indirect CCF. Coiling was safer than LEAs for the embolization of the indirect CCF.

[Carotid-cavernous fistulas]. / Sinus-cavernosus-Fisteln.

BACKGROUND: Carotid cavernous fistulas (CCFs) are rare but clinically significant vascular anomalies characterized by abnormal connections between the cavernous sinus and arteries. This overview presents a comprehensive analysis of anatomy, classification, clinical presentation, diagnosis, imaging, and therapy of CCFs. The cavernous sinus, a central venous structure in the brain, is of critical importance for understanding CCFs due to its proximity to key structures such as the internal carotid artery and cranial nerves. CLASSIFICATION: CCFs are classified into direct and dural types, with direct fistulas typically being high-flow and dural fistulas being low-flow. The symptomatology varies greatly and can range from noises in the head, diplopia, red eye, tearing, to blurred vision and headaches. The diagnostic assessment requires a combination of detailed medical history, neurological and ophthalmological examination, and the use of imaging techniques. METHODS: In imaging, computed tomography (CT) and magnetic resonance imaging (MRI) are crucial for depicting the anatomical structures and blood vessels, while digital subtraction angiography (DSA) is considered the gold standard for accurate representation of the fistula. The treatment of CCFs is complex and depends on the type of fistula, location, and clinical condition of the patient. CONCLUSION: This overview emphasizes the importance of precise diagnosis and individualized therapy to achieve optimal results and avoid complications. Ongoing developments in medical imaging and treatment techniques will continuously improve the treatment outcomes of patients with CCFs.

Carotid-cavernous fistula: A potential treatable cause of bilateral abducens palsy and conjunctival hyperemia.

OBJECTIVE: Carotid cavernous fistulas (CCFs) represent uncommon and anomalous communications between the carotid artery and the cavernous sinus. MATERIALS AND METHODS: Case report RESULTS: We present the clinical details and successful management of a previously healthy 44-year-old patient who presented with one-month worsening headache, bilateral abducens palsy and conjunctival injection. Imaging modalities including magnetic resonance imaging (MRI) with contrast and digital subtraction angiography (DSA) facilitated the diagnosis of CCF. The patient underwent endovascular coiling of the CCF, leading to neurological recovery and symptom remission. CONCLUSION: This case highlights the importance of promptly CCF diagnosis in patients with multiple cranial nerve palsies and conjunctival hyperemia. Moreover, it emphasizes the efficacy of endovascular coiling in achieving symptom remission.

Off-label use of large diameter Concerto fibered coils through a 0.017 inch microcatheter for transvenous embolization of indirect carotid-cavernous fistulas: two case reports.

BACKGROUND: A carotid-cavernous fistula is an abnormal communication between the arteries and veins within the cavernous sinus. While conservative management may be prudent in low risk cases, many patients require intervention and endovascular embolization has evolved as the preferred method of treatment. Embolization can be performed via either the transarterial or transvenous approach. One major challenge of the transvenous approach is the complex and variable compartmentation of the cavernous sinus, which often requires the use of low profile microcatheters to navigate and reach the fistulous point. Fibered coils are also preferred when performing transvenous embolization of carotid-cavernous fistula, as they are of higher thrombogenicity and allow for faster occlusion of the fistula. However, most low profile (0.017-inch) microcatheters are not able to deploy fibered coils based on the manufacturer's instructions. CASE PRESENTATION: We present two successful cases of off-label use of Medtronic Concerto fibered coils via a 0.017-inch microcatheter during transvenous embolization of carotid-cavernous fistula in a 60-year-old and an 80-year-old Chinese female, respectively. CONCLUSION: Our case series highlight the possibility of deploying large diameter (up to 10 mm) Concerto fibered coils through a low profile (0.017-inch) microcatheter in an off-label manner for transvenous embolization of indirect carotid-cavernous fistula.

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.

Post-traumatic carotid-cavernous fistula.

A 28-year-old woman who suffered a head injury 2 months before presented with a history of progressive right eye proptosis, ophthalmoplegia, and conjunctival injection. The radiological workup with a magnetic resonance imaging of the brain and cerebral angiography revealed a direct, high-flow, right post-traumatic carotid-cavernous fistula. An endovascular procedure was performed, and the carotid-cavernous fistula was successfully occluded with a progressive resolution of the complained symptoms.

Pressure-Lowering Effect of Interventional Fistula Occlusion in Secondary Glaucoma due to Orbital Draining Intracerebral Fistulae. / Drucksenkender Effekt der interventionellen Fistelokklusion bei Sekundärglaukom infolge orbital drainierender intrazerebraler Fisteln.

BACKGROUND: Carotid cavernous sinus fistulas (CSCF) are pathological connections of the internal and/or external carotid artery (and/or its branches) to the cavernous sinus. Ophthalmological symptoms and problems occur particularly when drainage is via the superior ophthalmic vein. MATERIAL AND METHODS: Seven eyes of six patients with a high-grade suspicion of CSCF were included in this retrospective monocentric study. Digital subtraction angiography (DSA) was performed in the included patients, where an interventional fistula closure was performed in the case of CSCF. Four of the six patients received a pre- and post-interventional day-night intraocular pressure profile. Furthermore, medical history, symptoms, visual acuity, slit lamp microscopic findings, and DSA findings were evaluated. RESULTS: The most common symptoms reported by patients were red eyes, diplopia, and exophthalmos. When the intraocular pressure (IOP) was measured, 83.33% of the patients showed increased values. The mean IOP in the day-night intraocular pressure profile in the affected eye before intervention was 23.5 (± 2.7) mmHg compared to 14.1 (± 2.3) mmHg in the healthy eye. A significant difference could thus be demonstrated in side comparison (p = 0.0047). The post-interventional measurement showed a mean IOP of 15.3 (± 1.0) mmHg in the affected eye and thus a significant difference to the pre-interventional measurement in the affected eye (p = 0.0018). Four of the six patients with CSCF were taking antiglaucomatous eye drops before the intervention, and two patients after the intervention. The number of antiglaucoma drugs used could also be reduced. CONCLUSION: Interventional fistula closure is an effective method for treating the secondary increase of IOP in CSCF. Successful closure of the fistula showed a significant reduction in IOP, which was not possible with the sole administration of antiglaucoma drugs. Radius-Maumenee syndrome should be considered as a differential diagnosis.

Extraocular muscle enlargement and proptosis in carotid cavernous fistulas.

PURPOSE: To evaluate the prevalence and pattern of extraocular muscle enlargement and proptosis in patients with carotid cavernous fistulas (CCF). METHODS: We conducted a retrospective study on patients with digital subtraction angiography (DSA) confirmed CCFs with neuroimaging (computed tomography or magnetic resonance imaging) performed prior to the DSA. The maximum extraocular muscle diameters were recorded. Extraocular muscles were considered enlarged if they were greater than two standard deviations above the normal muscle diameters. Proptosis was defined as the distance between the interzygomatic line to the anterior globe of ≥2 mm compared to the contralateral orbit or ≥21 mm. RESULTS: Forty orbits from 20 patients were included. The mean age of participants was 65 ± 15 years and 13 (65%) were female. Thirteen (65%) fistulas were indirect and seven (35%) were direct. There was enlargement of at least one muscle in 11 (27.5%) orbits, and this was not correlated with the type of fistula (direct/indirect). The inferior rectus was most commonly enlarged in seven orbits (17.5%), followed by the medial rectus in five orbits (12.5%). Proptosis was found in 17 (43%) orbits and was more common ipsilateral to the fistula (58% ipsilateral group vs 19% contralateral group, p < .01). CONCLUSION: Extraocular muscle enlargement was observed in over one-fourth of CCFs. When enlarged, the inferior and medial rectus muscles are most commonly involved. These findings may help clinicians and radiologists when evaluating the CT or MRI scans of patients with suspected CCFs.

Vascular Ehlers-Danlos syndrome with a Novel missense COL3A1 gene mutation present with bilateral spontaneous carotid-cavernous fistula: a case report.

This report describes a unique case of vascular Ehlers-Danlos syndrome (vEDS) characterized by multiple spontaneous direct carotid-cavernous sinus fistulas (CCF). The patient initially presented with ocular symptoms and was effectively treated with transarterial coil embolization. Five years later, the patient developed recurrent contralateral CCF that required complex endovascular techniques. Genetic testing identified a novel mutation in the COL3A1 gene, confirming the diagnosis of vEDS. This case report provides a near-term perspective on the identification of structural abnormalities in the COL3A1 protein to ensure the safety of endovascular therapy for patients with vEDS.