Spontaneous direct carotid-cavernous fistula with acute visual loss in an elderly patient: case report and review of the literature.

Carotid-cavernous fistulas are acquired vascular lesions, representing abnormal connections caused by a direct shunt or dural branches of the internal carotid artery and/or the external carotid artery connected to the cavernous sinus. We present an interesting, rare case of a spontaneous fistula with acute vision loss in an older patient. The patient was diagnosed with a direct carotid-cavernous fistula based on the clinical and radiological findings. We concluded that early diagnosis and etiological treatment could improve the prognosis of this type of carotid-cavernous fistula.