Unusual posterior hyaloid strand in a young child with optic disc pit maculopathy: intraoperative and histopathological findings.

BACKGROUND: The mechanism responsible for optic disc pit maculopathy is unclear, but abnormal vitreous structures, including the anomalous Cloquet's canal at the optic disc pit, have been suggested as important factors. CASE: We report the intraoperative and ultrastructural findings of an unusual posterior vitreous strand in the eye of an 8-year-old girl with optic disc pit maculopathy. OBSERVATIONS: The patient presented with decreased vision in the left eye. Examination of the left eye revealed a best-corrected visual acuity (VA) of 0.08 and a macular detachment associated with an optic disc pit. Vitrectomy was performed with the adjunctive use of triamcinolone acetonide intraoperatively. The presence of an unusual posterior hyaloid strand tightly attached to the margin of the optic disc pit was noted. An unusual movement of this strand was observed during the surgery. The strand was excised, and fluid-gas exchange was performed using gas tamponade with 20% SF(6). After 12 months, a complete macular reattachment was obtained, with the VA improving to 1.2. Electron microscopic examination of the removed strand revealed abundant thick collagen fibrils with a frame of fine fibrils.
CONCLUSION: The unusual posterior vitreous strand connected to the optic disc pit may have contributed to the pathogenesis of maculopathy in this young child.