Progressive Outer Retinal Necrosis (PORN)

Progressive outer retinal necrosis (PORN) is a rare form of acute retinal necrosis (ARN) found in patients with severe immunosuppression, such as from HIV/AIDS.

This patient was lost to follow-up after the visit at which these images were taken. We are sure he went on to develop bilateral blindness.

Learning Points:
Both ARN and PORN are most commonly caused by the Herpes zoster virus. ARN, which occurs in immunocompetent individuals, is a rapidly progressive panuveitis with hemorrhagic and ischemic retinal necrosis that typically begins in the retinal periphery.

In contrast, PORN presents as a patchy, more posterior, and apparent outer non-hemorrhagic retinal necrosis in an otherwise relatively quiet eye. The white patches rapidly progress to more confluent areas of full-thickness necrosis.

Intravitreal ganciclovir and foscarnet can sometimes preserve vision, although the visual outcomes are usually extremely poor. Patients are also at risk for subsequent retinal detachment.