Conditions necessary for the formation of serous detachment. Experimental evidence from the cat
M. F. Marmor and X. Y. Yao
Department of Ophthalmology, Stanford University School of Medicine, Calif.
OBJECTIVE: To evaluate experimentally the conditions necessary for the
formation of serous detachments. METHODS: Selective injury to the retinal
pigment epithelium (RPE) and choriocapillaris was produced in cats using
weak laser burns and intense diffuse light, with or without
photosensitization with rose bengal. The fundi were analyzed by
observation, fluorescein angiography, and histologic examination. RESULTS:
Injuring the RPE alone did not cause detachments. Focal injury to the RPE
and choriocapillaris caused moderate detachment only when an area
surrounding the focal leakage site had been subjected to light damage.
Diffuse injury to the RPE and choriocapillaris caused broader detachments.
CONCLUSIONS: Three conditions are necessary for serous detachments to form:
(1) a source of fluid pressure, (2) a defect in the blood-retinal barrier
(entry site), and (3) an area of impaired fluid transport beyond the site
of leakage (if fluid is to accumulate over a broader area).
