Visual field defect after posterior spine fusion.

STUDY
DESIGN: Case report and literature review.
OBJECTIVES: Review cases and literature regarding visual loss following posterior spine fusion for scoliosis and emphasize right-to-left atrial shunt as a risk factor for paradoxical embolus resulting in a postoperative visual field defect. SUMMARY OF BACKGROUND DATA: The existing literature discusses various possible etiologies of postoperative visual loss including direct pressure, hypotension, blood loss, and anemia. One study shows higher rates of cerebral microemboli in patients with right-to-left atrial shunts.
METHODS: Chart and literature review.
RESULTS: A paradoxical embolus to a branch of the central retinal artery resulted in a unilateral quadrant defect (homonymous quadrantanopsia) in a girl with a previously undiagnosed right-to-left atrial shunt.
CONCLUSIONS: Right-to-left atrial shunts may predispose to cerebral emboli during scoliosis surgery. These emboli may be a cause of postoperative visual field defects.