Sawsan R. Nowilaty, MD

Purpose:

To describe the visual outcome, the anatomic and multifocal electrophysiology features in a patient with retained subfoveal perfluoro-n-octane liquid for ten years.

Methods:

A 16-year old boy underwent retinal detachment repair with perfluoro-n-octane (PFO) assisted drainage of subretinal fluid and gas tamponnade. Postoperatively a PFO bubble was identified under the foveal center but observation was elected. Follow up of the visual function and foveal anatomy continued for ten years with Snellen visual acuity (VA) testing, visual fields, fundus photography, fluorescein angiography (FA) and ultrasonography. Optical coherence tomography (OCT) and multifocal electroretinography (mfERG) were later added to complete the assessment.

Results:

At three months the VA was 20/80 and the fovea stretched thinly over the PFO bubble. Ten years later, the fundus, angiographic and echographic appearances are unchanged and the PFO volume is stable. The OCT demonstrates the elevated thin fovea “wrapping” over the bubble and the preservation of a normal retinal anatomy beyond the bubble without thinning or structural disorganization. The mfERG demonstrates a mild decrease in the amplitude of the central foveal responses, but the remaining perifoveal responses are within normal limits. VA remains at 20/40.

Conclusion:

Because of their potential toxicity perfluorocarbon liquids are removed thoroughly and reports on long-term consequences of chronic subfoveal PFO retention are unavailable. In this case the small subfoveal PFO bubble was well tolerated with minimal visual dysfunction or retinal changes for over 10 years.

Take-home message:

A small subfoveal PFO bubble may be left in place without major negative impact on central visual function.