Carotid-cavernous fistula in a child after minimal orbital trauma

Abstract

We present a case of a direct carotid-cavernous fistula in a seven-year-old child with an unclear history of relatively mild orbital trauma. The child was initially diagnosed with a cranial nerve VI palsy, then admitted with a presumed diagnosis of orbital cellulitis. Further examination, including formal angiography, revealed a direct carotid-cavernous fistula with significant cortical venous drainage requiring prompt intervention. Treatment of the fistula by coil occlusion was successful. This case illustrates the importance of recognizing and understanding the pathophysiology and treatment of this rare but potentially fatal entity. CASE REPORT A seven-year-old boy presented to the emergency department with an edemetous, ecchymotic right eye and a right cranial nerve VI palsy one week after sustaining reportedly blunt trauma to his right medial orbit from colliding into a fence post. The diagnosis of “possible orbital fracture” was made. Noncontrast computed tomography of the head and orbits was ordered. He was given oral and topical antibiotics and instructed to return to the eye clinic in two days. On follow-up examination by an ophthalmology resident, the patient reported a different history, stating that he had been “poked” in the eye by a fence wire. His uncorrected visual acuity was 20/50 in his right eye and 20/40 in his left. Pupillary examination was normal. Intraocular pressure in his right eye was 26 mm Hg. His right eye was proptotic though nonpulsatile. Hertel measurements were not documented. A right esotropia and hypotropia, lateral gaze restriction, chemosis, and conjunctival hyperemia with torturous vessels were noted (Figure 1).