Outcomes of surgery for retinal detachment in eyes having choroidal coloboma

Ocular coloboma-a comprehensive review for the clinician

Typical ocular coloboma is caused by defective closure of the embryonal fissure. The occurrence of coloboma can be sporadic, hereditary (known or unknown gene defects) or associated with chromosomal abnormalities. Ocular colobomata are more often associated with systemic abnormalities when caused by chromosomal abnormalities. The ocular manifestations vary widely. At one extreme, the eye is hardly recognisable and non-functional—having been compressed by an orbital cyst, while at the other, one finds minimalistic involvement that hardly affects the structure and function of the eye. In the fundus, the variability involves the size of the coloboma (anteroposterior and transverse extent) and the involvement of the optic disc and fovea. The visual acuity is affected when coloboma involves disc and fovea, or is complicated by occurrence of retinal detachment, choroidal neovascular membrane, cataract, amblyopia due to uncorrected refractive errors, etc. While the basic birth anomaly cannot be corrected, most of the complications listed above are correctable to a great extent. Current day surgical management of coloboma-related retinal detachments has evolved to yield consistently good results. Cataract surgery in these eyes can pose a challenge due to a combination of microphthalmos and relatively hard lenses, resulting in increased risk of intra-operative complications. Prophylactic laser retinopexy to the border of choroidal coloboma appears to be an attractive option for reducing risk of coloboma-related retinal detachment. However, a majority of the eyes have the optic disc within the choroidal coloboma, thus making it difficult to safely administer a complete treatment.

OUTCOMES OF VITRECTOMY WITH SILICONE OIL TAMPONADE FOR MANAGEMENT OF RETINAL DETACHMENT IN EYES WITH CHORIORETINAL COLOBOMA

PURPOSE

To estimate the outcomes of retinal detachment in eyes with chorioretinal coloboma managed by pars plana vitrectomy and silicone oil tamponade.

METHODS

A retrospective chart review of 10 eyes (10 patients) who underwent pars plana vitrectomy for retinal detachment with chorioretinal coloboma.

RESULTS

The average age at the time of the surgery was 29.8 ± 19.7 years. The mean follow-up period was 28.8 ± 28.4 months. The mean silicone oil tamponade duration was 9.8 ± 3.5 weeks. Of 10 eyes, 4 (40%) had retinal breaks outside the coloboma, 4 (40%) had breaks inside the coloboma, 1 (10%) had breaks inside and outside the coloboma, and in 1 eye (10%); the causative retinal break was not localized. Preoperatively, the mean visual acuity was 20/2,500 (n = 9), and 1 (10%) was recorded as "Not CSM." At the final examination, the mean visual acuity for the patients with measurable visual acuity was 20/200 (P = 0.06), and in the remaining eye was recorded as light perception. The retina was finally reattached in nine eyes (90%). Postoperative complications included cataract in three (30%), persistent elevated intraocular pressure in one (10%), band keratopathy in one (10%), and proliferative vitreoretinopathy in one (10%).

CONCLUSION

Complete pars plana vitrectomy with or without lensectomy, laser photocoagulation around the peripheral retina, around all the peripheral breaks and around the colobomatous area, and silicone oil tamponade is effective for retinal detachment in eyes with chorioretinal coloboma. Silicone oil removal as early as possible did not increase the risk of redetachment and seems to reduce the incidence of oil-related complications in such cases.