Isolated Lenticular Coloboma in an Atypical Location With Early Cataract Formation: A Case Report

A coloboma refers to an embryological defect of the eye due to incomplete closure of the embryological fissure in development. Lenticular colobomas are defects of the capsular bag due to an absence of zonules, resulting in a characteristic notching of the lens; however, they are not true colobomas as there is no loss in lens tissue. These defects are often congenital and are typically seen in a unilateral and inferonasal position. In this case report, we outline the presentation of a 38-year-old female patient who had been experiencing reduced vision and floaters in one eye following an injury. When seen in eye casualty, the patient was noted to be amblyopic with a superotemporal lens coloboma observed in the left eye (LE). The affected LE had a reduced visual acuity of 6/30 compared to 6/6 in the right eye with mild nuclear sclerosis in the affected lens. Following 12 months of conservative management, the lens remained stable with no phacodonesis. The history of recent trauma and early cataract formation make this case unique. The history of trauma and subsequent visual deterioration raise the possibility of an underlying zonular defect unmasked by injury, highlighting the diagnostic uncertainty that can arise in atypical presentations.