A Diamond-Like Crystalline Cataract: An Atypical Presentation Of Traumatic Cataract In An Occult Intraocular Foreign Body In Children – A Single Case Report.

To report an atypical diamond-like crystalline cataract in a pediatric patient with occult intraocular foreign body (IOFB). This demonstrates the unique features of a lens with a traumatic cataract, highlighting the need for further investigation.

Department of Ophthalmology, Queen Sirikit National Institute of Child Health and Rajavithi Hospital.

A 9-year-old Thai boy was referred for a complicated cataract on the right eye. He was previously diagnosed with presumed Familial Exudative Vitreoretinopathy (FEVR) treated with pars plana vitrectomy (PPV), membrane peeling, and multiple anti-vascular endothelial growth factor (anti-VEGF) injections for 1 year. After undergoing treatment, he developed an unusual cataract and was referred to our center. Birth, medical, and family histories were unremarkable. Right eye visual acuity was light projection; the left eye was 20/20. Examination of his right eye revealed an atypical, diamond-like dense cataract with posterior synechiae, obscuring the posterior pole. Due to opaque media, B-scan ultrasonography (USG) revealed a superonasal subchoroidal hyperechoic lesion with posterior acoustic shadowing, suggesting an intraocular foreign body (IOFB). A computed tomography (CT) scan confirmed a radiopaque IOFB. The diagnosis was revised to an atypical pediatric traumatic cataract secondary to an occult IOFB. He underwent lens aspiration without intraocular lens implantation, PPV,  successful IOFB extraction, and silicone oil injection. During lens extraction procedure, multiple polychromatic diamond-like crystalline particles with capsular fibrosis were aspirated with liquefied lens material. This highlights the unusual presentation of a traumatic cataract associated with an occult IOFB. A repeat postoperative CT scan confirmed IOFB removal; visual acuity remained light projection.

This study reports an atypical presentation of a pediatric cataract with occult IOFB. Diamond-like crystalline lens particles serve as a clinical clue for an occult traumatic etiology. Even with a minute or denied trauma history, unusual lens characteristics increase the index of suspicion. Preoperative USG and CT scan can help prepare surgical planning and prevent intraoperative surprises.