Molteno implants and operating microscope-induced retinal phototoxicity. A clinicopathologic report

Area of Science:

• Ophthalmology
• Histopathology
• Ocular Oncology

Background:

• A 75-year-old male patient with a complex ocular history underwent postmortem examination.
• Previous surgeries included cataract extraction, multiple penetrating keratoplasties, laser trabeculoplasty, and Molteno implants.
• A history of operating microscope-induced retinal phototoxic lesion was noted.

Observation:

• Anterior segment histopathology revealed evidence of prior surgeries with minimal tissue reaction.
• Ultrastructural analysis suggested aqueous percolation around Molteno implants.
• Posterior segment examination identified retinal pigment epithelial hyperplasia and photoreceptor atrophy at the phototoxic lesion site.

Findings:

• Histopathology confirmed previous surgical interventions and identified unexpected posterior segment pathology.
• Evidence of aqueous humor leakage from Molteno implants into the conjunctiva was observed.
• Retinal pigment epithelial hyperplasia, photoreceptor atrophy, cystoid macular edema, and a preretinal membrane were noted.

Implications:

• This case highlights the long-term effects of complex ocular surgeries and iatrogenic retinal injury.
• Understanding the behavior of Molteno implants and phototoxic lesions is crucial for managing glaucoma and retinal damage.
• The findings underscore the importance of detailed postmortem examination in evaluating ocular disease progression and treatment outcomes.