Branch Retinal Artery Occlusion in a Patient with Patent Foramen Ovale
A 29-year-old woman presented with superior visual field defect of 30 minutes’ duration in her left eye which had suddenly appeared after swimming.\nOn ocular examination, visual acuity was 20/20 and 20/32 in her right and left eyes, respectively. A weak relative afferent papillary defect was identified on the affected side. No remarkable finding was observed in the anterior segment of either eye. Funduscopic examination revealed a calcified white embolus at the first bifurcation of the inferior temporal artery of the left retina. Except for mild retinal edema in the left eye, no other ocular abnormality was noted.\nWith a diagnosis of BRAO, the patient was treated with oral acetazolamide, topical timolol, ocular massage, followed by anterior chamber paracentesis. Visual field loss partially recovered within 15 minutes after initiation of treatment, meanwhile the embolus moved to the third bifurcation level.\nVisual field testing (Humphrey Field Analyzer; Carl Zeiss, Jena, Germany) was performed two days after the onset of symptoms and disclosed a superior visual field defect in the left eye (). At the same time, fluorescein angiography depicted no embolus and delayed filling of the affected artery ().\nAn initial review of the patient’s medical history revealed no systemic disease. The patient underwent an extensive diagnostic work-up consisting of neurology, rheumatology, cardiology, and hematology consultation, carotid color Doppler ultrasound evaluation, and complete laboratory testing to determine the source of embolization. These studies however, could not identify the cause of the condition. Accordingly, further echocardiographic studies were performed in search of a probable cardiac source which identified a small PFO which was 1 to 2 mm in diameter (A). TEE illustrated abnormal passage of agitated saline microbubbles through the PFO; following peripheral administration of agitated saline, about 10 micro-bubbles were detected to pass from the right to the left atrium via the PFO with Valsalva maneuver (B). The inter- atrial septum was not aneurysmal and all other tests were normal.\nSubsequently, the patient received long- term oral aspirin and developed no other embolic event over a two-year follow-up course.