Volumetric analysis of macular edema by scanning laser tomography in immune recovery uveitis.

OBJECTIVES To evaluate the macular volume in eyes with immune recovery uveitis (IRU) and to describe a new method to quantify macular edema with the use of confocal scanning laser tomography (cSLT). METHODS A prospective study was performed to assess the macular volume with cSLT in patients with and without IRU. None of the patients enrolled had cytomegalovirus retinitis within 3000 micro m of the fovea. Eight eyes had healed cytomegalovirus retinitis with IRU and cystoid macular edema (group A); 4 eyes had healed cytomegalovirus retinitis with IRU and clinically normal maculas (group B); 18 eyes had no IRU (group C); and 3 eyes underwent pars plana vitrectomy and epiretinal membrane peeling for epiretinal membranes associated with cystoid macular edema and IRU (group D). Patients with IRU underwent standard clinical examinations and cSLT. On cSLT, volume above the reference plane was calculated within a fovea-centered circle of 3 mm in diameter. We devised a novel system for defining the reference plane. Measurements were performed 3 times in masked fashion and the mean was used for analyses. RESULTS The mean macular volume was highest in group A (1.97 mm3). This was significantly higher (P<.001) than that in groups B (1.15 mm3), C (1.02 mm3), and D (0.86 mm3). CONCLUSIONS Macular edema in patients with IRU can be consistently and objectively quantitated by cSLT. The method of defining the reference plane used in our study is novel and can be used in other disorders causing macular edema.