Caroticocavernous Fistula Treatment & Management
- Author: Michael G Nosko, MD, PhD; Chief Editor: Allen R Wyler, MD more...
Medical Therapy
In the acute setting of vision loss and/or paralysis of cranial nerves, glucocorticosteroids (eg, dexamethasone) may be used while waiting for definitive diagnostic studies and treatments.
Surgical Therapy
The definitive management of a caroticocavernous fistula is obliteration of the fistulous connection with restoration of normal arterial and venous flow. This is achieved most often through an endovascular approach. After complete delineation of the fistulous tract, an approach can be planned to close the fistula.
Type-A fistulas usually are approached through the internal carotid artery. A detachable balloon then can be positioned to occlude the fistula while maintaining patency of the internal carotid artery. Venous approaches through the internal jugular vein and the petrosal sinus may allow access to the fistula from the venous side. Guglielmi detachable coils also may be used and are becoming increasingly popular.
Type B, C, and D fistulas have smaller fistulous connections and usually are not amenable to the aforementioned treatment approaches. Carotid self-compression for 20-30 seconds 4 times per hour may lead to thrombosis of the fistula. Patients are instructed to compress the carotid artery on the side of the lesion using their contralateral hand. Should the patient develop cerebral ischemia during the compression, the contralateral hand likely will be affected, releasing the compression.
If compression is not effective or if a more rapid intervention is indicated, selective endovascular embolization of the fistula through the external carotid artery usually is effective. Several choices of embolic material are available, although polyvinyl alcohol usually is preferred.
Occasionally a fistula may require an endovascular approach through the superior ophthalmic vein. This requires surgical exposure of the vein to allow placement of the catheter.
Direct surgical exposure and obliteration of the fistula has been described. This rarely is indicated because endovascular approaches have been developed.
Severely refractory fistulas can be treated by surgical or endovascular sacrifice of the internal carotid artery. This too, rarely is indicated.
Follow-up
Patients usually require a follow-up angiogram to ensure that the fistula has not recurred or that alternate fistulous pathways have not developed.
Complications
Complications in untreated lesions usually are limited to visual loss, cranial nerves paralysis, and the cosmetic concerns of proptosis.
Complications of treatment include the standard complications of cerebral angiography. Arterial and venous compromise also may occur, yielding cerebral or retinal ischemia and resultant infarction.
Outcome and Prognosis
Patients with caroticocavernous fistulas generally have a good prognosis. These fistulas are associated with a high incidence of spontaneous resolution. Persistent lesions respond well to intervention. The risk of nonophthalmologic neurological complications is not significant; however, persistent untreated lesions may cause significant visual complications.
Future and Controversies
As techniques for endovascular stenting are developed further, internal carotid artery stenting across the fistula may have a role. This may provide a safer treatment option with respect to maintaining patency of the internal carotid artery while obliterating the fistula.
Barrow DL, Spector RH, Braun IF. Classification and treatment of spontaneous carotid-cavernous sinus fistulas. J Neurosurg. Feb 1985;62(2):248-56. [Medline].
Karaman E, Isildak H, Haciyev Y, Kaytaz A, Enver O. Carotid-cavernous fistula after functional endoscopic sinus surgery. J Craniofac Surg. Mar 2009;20(2):556-8. [Medline].
Hieshima GB, Cahan LD, Mehringer CM. Spontaneous arteriovenous fistulas of cerebral vessels in association with fibromuscular dysplasia. Neurosurgery. Apr 1986;18(4):454-8. [Medline].
Bacon KT, Duchesneau PM, Weinstein MA. Demonstration of the superior ophthalmic vein by high resolution computed tomography. Radiology. Jul 1977;124(1):129-31. [Medline].
Dandy WE, Follis RH Jr. On the pathology of carotid-cavernous aneurysms (pulsating exophthalmos). Am J Ophthalmol. 1941;24:365-385.
Debrun GM, Vinuela F, Fox AJ. Indications for treatment and classification of 132 carotid-cavernous fistulas. Neurosurgery. Feb 1988;22(2):285-9. [Medline].
Hamby WB. Carotid-cavernous fistula. Springfield, Ill: Charles C Thomas. 1966.
Newton TH, Hoyt WF. Dural arteriovenous shunts in the region of the cavernous sinus. Neuroradiology. 1970;1:71-81.
Serbinenko FA. Balloon catheterization and occlusion of major cerebral vessels. J Neurosurg. Aug 1974;41(2):125-45. [Medline].
Walker AE, Allegre GE. Carotid-cavernous fistulas. Surgery. 1956;39:411-422.
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