Clinicopathological correlation of deep retinal vascular anomalous complexin age related macular degeneration

Aims-To analyse the histopathology of "deep retinal vascular anomalous comp lex" or "chorioretinal anastomosis". Methods-Six patients with a deep retinal vascular anomalous complex (age ra nge 66-88 years) had fundus photography and fluorescein angiography not mor e than 14 days before foveal translocation surgery. Four patients were also documented with indocyanine green angiography. The surgical specimens were serially sectioned and stained in a stepped fashion with Masson trichrome, periodic acid Schiff, and phosphotungstic acid haematoxylin, a histochemic al stain for fibrin. Results-A subretinal fibrovascular membrane was surrounded by a rim consist ing of diffuse drusen (basal laminar deposits), retinal pigment epithelium, and amorphous, fibrinous material interspersed with remains of outer segme nts in all specimens. In two specimens vascular structures were identified that left the specimen towards the retina. Amorphous material with the rema ins of outer segments was not found on the retinal side of the fibrovascula r tissue itself but in four specimens a small neuroretinal portion (outer n uclear layer) was adherent to the complex. In three specimens a thin fibroc ellular membrane was seen at the choroidal side of the diffuse drusen. Conclusion-Deep retinal vascular anomalous complex represents histologicall y neovascularisation growing out of the neuroretina, into the subretinal sp ace, which mimics choroidal neovascularisation. The term therefore appears rightly chosen.