Abstract
The retinal disorder of central serous chorioretinopathy (CSC) is characterized most typically by the appearance of a serous blister of fluid in the macula of one eye. Attacks are often self-limited, and fluorescein angiography shows leakage of fluid from the choroid through a small defect in the retinal pigment epithelium (RPE). The disease was thought for many years to be a local and unilateral phenomenon, though related to systemic factors such as stress and corticosteroid usage.
We have been studying CSC patients with a variety of clinical electrophysiologic tests, and these paint a somewhat different picture. The conventional electroretinogram (ERG) and electro-oculogram (EOG) appear normal in most patients. However, the multifocal ERG (mfERG) shows depression not only of signals from the region of serous detachment, but signals across the entire posterior pole of both eyes. A test of RPE function recently described by Arden and Wolf, using alcohol to stimulate the standing potential, shows depressed signals bilataerally in CSC patients. In contrast, other non-photic tests (acetazolamide and hyperosmotic infusion) are normal.
These results indicate that there are specific and subtle functional changes in the retina and RPE in CSC that can be recognized by surveying a variety of electrophysiologic measures. Our results show that there is widespread and bilateral pathology in this condition, so that the focal leakage seen clinically is probably an unfortunate complication rather than the primary disease process. CSC may represent a choroidal vasculopathy conditioned by stress hormones and other causes, with secondary dysfunction of the overlying RPE and retin