Edmund Y.M. Wong, MD (Singapore, Singapore), Boon Kwang Loh, MBBS, MRCS (Singapore, Singapore), Jocelyn Chua, MBBS, MRCS (Singapore, Singapore), Caroline K. Chee, MBBS, FRCSEd, FRCOphth (Singapore, Singapore)

PURPOSE:

To report the favorable surgical outcome in a rare case of combined hamatoma of the retina and retinal pigment epithelium (RPE) extending to the fovea despite reduced amplitudes of foveal and perifoveal preoperative multifocal electroretinogram.

METHODS:

A 44-year old man of Chinese descent presented with 6-month duration of painless, gradual reduction of vision of his right eye. Pre- and postoperative tests performed included visual acuity (VA), retinal examination and photography, optical coherence tomogram (OCT), fluorescein angiography (FA), indocyanine green angiography (ICG), and multifocal electroretinogram (mfERG). Pars plana vitrectomy with membrane peeling was performed. Intraoperative findings were noted.

RESULTS:

Pre-operative VA was 20/240. Retinal examination revealed an epiretinal membrane overlying a combined hamartoma of the retina and RPE that extended from the inferior macular vascular arcade to the fovea. OCT demonstrated vitreomacular traction, epiretinal retinal membrane, retinal folds, increased retinal thickness and cystoid macular edema. Fluorescein angiography showed vessel tortuosity, early blocked fluorescence, mid-phase patchy hyperfluoresence and late leakage. Indocyanine green angiography showed patchy hyperfluorescence and late hypofluorescence. mfERG showed reduced foveal and perifoveal
amplitudes. Intraoperatively, it was noted that the epiretinal membrane was multilaminar, with the deeper layers intermingled with the hamatomatous tissue. Post-operatively, VA recovered to 20/150 within 3 months. There was reduced macular edema, and improved visualization of the retina and retinal vessels previously obscured by the epiretinal membrane.

CONCLUSION:

Surgical removal of vitreomacular traction and epiretinal membrane associated with combined hamartoma of the retina and RPE extending to the fovea improved vision in a case with relatively short duration of symptoms. Reduced mfERG amplitudes are not necessarily a surgical contraindication, but may suggest lower potential for full visual recovery.