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The diagnosis of carotid-cavernous fistulas (CCFs) requires a high index of suspicion; a delay in treatment may lead to irreversible damage.
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Angiography remains the gold standard for diagnosing CCFs.
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The endovascular approach is the first-line treatment given the low complication rate and the favorable long-term outcome.
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The agents used for the endovascular management are balloons, coils, liquid embolic substances, and stents.
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Certain fistulas may require multiple agents or multiple sessions for
Endovascular Treatment of Carotid-Cavernous Fistulas
Section snippets
Key points
Relevant anatomy
The CS is located lateral to the sella turcica, expanding from the superior orbital fissure to the apex of the petrous bone. The CS is neither a sinus nor cavernous per se, rather it is a reticulated structure, formed by an assembly of multiple thin-walled veins, as demonstrated by Parkinson and later by Hashimoto and colleagues.1, 2 Therefore, the name lateral sellar compartment was proposed to be more accurate and to avoid any misinterpretation.2, 3 The importance that this distinction
Fistula classification and characteristics
CCF is sorted according to its cause, hemodynamic behavior, and angioarchitecture. Barrow and colleagues5 classified the CCFs in to 4 distinct types (A, B, C, and D) depending on the arterial supply. This classification is preferred because it encompasses indirectly the cause and the hemodynamic features; it also has a therapeutic implication.
Pathophysiology and clinical presentation
The short-circuiting of the arterial blood increases the pressure in the CS leading to flow reversal. The flow then may follow any draining pattern producing venous hypertension and/or thrombosis. The signs and symptoms depend on the drainage pathway, the presence of collaterals, and finally the size and location of the CCF.6 Table 2 lists the symptoms with their underlying physiopathology. The most frequent complains are in the orbital region.6, 7 Anterior drainage leads to orbital vein
Workup
The best initial tests used when CCF fistula is suspected for the reasons mentioned above are computed tomography (CT) or magnetic resonance (MR). These tests can confirm the clinical symptoms by visualizing the proptosis, the cerebral edema, and the cerebral hemorrhage. Signs and symptoms that suggest CCF are the following: enlargement of the extraocular muscles; engorgement of the SOV; dilatation of the facial vein; expansion of the ipsilateral CS, which can be described as pseudoaneurysmal
Treatment
The goal of the treatment of CCF is to restore the normal flow and occlude the fistula. The different options are conservative management, open surgery, stereotactic radiosurgery, and endovascular surgery. As discussed previously, the treatment depends on the patient's risk factor and the fistula characteristics. The lower risk of the endovascular approach when compared with surgery and the growing advances in this domain rendered the endovascular approach the treatment of choice for CCF
Endovascular treatment
As previously discussed, endovascular treatment is the modality of choice in both direct and indirect fistulas. This treatment can be used for emergency as well as elective treatment. The agents mostly used in endovascular treatment are detachable balloons, platinum detachable coils, liquid embolic materials, and recently, stents. These agents can be used alone or in combination. To gain access to the fistula, a transarterial (Fig. 1) or a transvenous (Fig. 2) approach can be used. Choosing the
Outcome
Closure of the fistula has been reported in 80% to 99% of direct and indirect fistulas.10, 22 The treatment might require combination treatment and sometimes multiple sessions. Meyers and colleagues10 managed to cure indirect CCF by transvenous embolization using coil and liquid embolic agents in 90% cases, of which 30% needed more than 2 procedures.10 Clinical improvement needs hours to days, but complete resolution may take up to 6 months.22 Notable complications are listed in Tables 4 and 5.
Summary
Endovascular treatment of CCF is an ever-advancing domain. This mode is the treatment of choice for direct and indirect CCF with a small complication and a high success rate. The multitude of agents used and the pathways leading to the CS offer a variety of treatments that can be tailored depending on the fistula type and the patient characteristics.
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Carotid-cavernous fistula: A potential treatable cause of bilateral abducens palsy and conjunctival hyperemia
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2024, International Journal of Surgery Case ReportsPost-traumatic carotid-cavernous fistula
2023, HeliyonCerebrovascular injuries in traumatic brain injury
2022, Clinical Neurology and NeurosurgeryCitation Excerpt :DSA should be performed thereafter to confirm the diagnosis and potentially treat the lesion. Given the lower rate of complications, endovascular therapy has become the treatment of choice for CCFs [104,110]. Common methods of treatment for direct CCFs include detachable platinum coils or flow diversion [110].
Flow diversion in direct carotid-cavernous fistula refractory to multiple coil embolizations: case report and review of the literature
2022, Journal of Stroke and Cerebrovascular Diseases
Disclosure: Dr P. Jabbour is a consultant at Covidien.
Conflict of Interest: The authors declare no conflict of interest.