Methods: Twenty eyes of 16 patients with active OT between were included. All patients underwent a full ophthalmic examination including optical coherence tomography. The anti-toxoplasma antibodies and IgG-avidity were investigated with the ELISA method.Results: Baseline central macular thickness (CMT) was thicker in eyes with toxoplasma IgM-positive than with IgM-negative (272.8 vs. 210.1?m, p=0.04, Cohen?s d=1.63). However, baseline CMT in eyes with low IgG avidity was not statistically different from eyes with high IgG avidity although a high effect size coeffi cient was present (442.0 vs. 227.0 ?m, p=0.40, Cohen?s d=2.95). No difference was present between recurrent and non-recurrent cases in terms of CMT (263.0 vs. 295.9 ?m, p=0.66, Cohen?s d=0.25). While no statistically signifi cant difference was present between the fi nal VA and the IgM positivity and IgG avidity (p>0.05; Phi coefficients of 0.56 and 0.44, respectively) and recurrence and the IgM positivity and IgG avidity (p>0.05; Phi coeffi cients=0.41 and 0.26, respectively), the effect size coeffi cients were clinically signifi cant. There was a strong positive correlation between the fi nal VA and the baseline VA and CMT (r=0.92 and r=0.79 respectively; p<0.01).

Conclusions: Signifi cant linear relationships were observed between baseline CMT, fi nal VA and recurrence and toxoplasma IgMpositivity and IgG-avidity. The fi nal VA was correlated with the baseline VA and CMT. Keywords : Anti-Toxoplasma IgG; anti-Toxoplasma IgM; IgG-avidity test; recurrence; ocular toxoplasmosis