The dragged-fovea diplopia syndrome: Clinical characteristics, diagnosis, and treatment

Purpose: To identify the clinical characteristics of the dragged-fovea diplopia syndrome, to introduce a simple diagnostic test that aids in the evaluation of such patients, and to provide a simple treatment option to improve the diplopia in some of these patients. Design: Retrospective, observational case series. Participants: Ninety-five affected eyes in 83 consecutive patients seen between January 1, 1993, and August 9, 2004, who were diagnosed with the dragged-fovea diplopia syndrome at one institution. Methods: We reviewed the records of 222 patients who have been seen in the Krieger Children's Eye Center at The Wilmer Institute since 1993 with a diagnosis of maculopathy, internal limiting membrane, or dragged fovea. We collected ocular findings and history for those patients who reported binocular diplopia that was not amenable to prism therapy and not secondary to acquired strabismus. Main Outcome Measures: We recorded the presence of metamorphopsia on Amsler grid testing or other clinical evidence of macular wrinkling, response to prism trial, response to the small-field central fusion test (lights on-off test), and response to partial occlusion with Scotch Satin tape (3M Co., St. Paul, MN). Results: Ninety-five affected eyes in 83 patients met the criteria for inclusion in the study. All patients who were tested with the lights on-off test (n = 69) responded positively, demonstrating rapid central fusion with room lights off, and recurrence of central diplopia with peripheral fusion with room lights on. Forty-six patients (of 64 tested) were receptive to monocular occlusion with Scotch Satin tape. Conclusions: The dragged-fovea diplopia syndrome consists of central diplopia in the presence of peripheral fusion, secondary to dragging of the fovea in one or both eyes by retinal disease. The central diplopia cannot be eliminated by prism therapy or eye muscle surgery. The lights on-off test has proved pathognomonic for this syndrome, and many patients have benefited from partial monocular occlusion with Scotch Satin tape.