An unusual case of iris and lens colobomas: A case report.

Ocular colobomas are unusual congenital anomalies arising from abnormal ocular development and may involve different ocular structures, including the iris and lens. Typical ocular colobomas predominantly involve the inferonasal quadrant, in accordance with the inferonasal location and closure pattern of the fetal fissure. Atypical colobomas outside this region are unusual and may complicate clinical evaluation and surgical planning. We report the case of a 49-year-old male with congenital inferonasal iris coloboma associated with a superotemporal lens coloboma, sectorial cataract, superior posterior subcapsular cataract and localized zonular absence. Ultrasound biomicroscopy demonstrated localized lens thickening and increased sphericity corresponding to the area of zonular defect. Given the limited extent of zonular involvement and intraoperative capsular bag stability, phacoemulsification with in-the-bag intraocular lens implantation was performed without additional capsular support. Postoperatively, the intraocular lens remained well centered during two-year follow-up, and best-corrected visual acuity improved significantly.