Orthoptic problems of macular rotation with and without muscle surgery

Background In spite of new therapeutic approaches the treatment of age related macular degeneration remains unsatisfying. Macular rotation is so far only a rarely employed surgical procedure, where the macula is translocated to an area with intact retinal pigment epithelium. The aim of this study was to elucidate the orthoptic problems of macular rotation and describe possible treatment modalities. Patients and method Between February and July of 1997 a macular rotation was performed in 8 patients with exsudative macular degeneration, followed by silicone oil removal and implantation of an intraocular lens. In 3 out of 8 patients the oblique muscles were transposed at the beginning of the surgery to produce an excylotropia. In all patients visual acuity for distance and near was determined pre-and postoperatively along with a complete orthoptic status including measuring of cyclotropia. Mean postoperative follow-up was 5.5 months. Results Due to the unilateral ectopia of the macula all patients presented with a postoperative strabismus with vertical deviation of 2 degrees to 10 degrees. The change of the visual axis resulted in a displacement of the pupillary rifler. The patients described a cyclotropia of 12 degrees to 45 degrees corresponding to the ophthalmoscopically estimated angle of retinal rotation. Patients after surgery of the oblique muscles showed less cyclotropia with an angle of 12 degrees to 20 degrees. They were less disturbed by diplopia and tilted visual impression than those without muscle surgery. All patients exhibited an abnormal head position with chin up and tilt to the side of the operated eye. Conclusion Macular rotation always causes diplopia because of the unilateral ectopia with cyclotropia and vertical deviation. These problems can be considerably reduced by combining macular rotation surgery with oblique muscles surgery. It may well be that in the future these problems can be completely resolved by additional surgery on the rectus muscles.