Materials and Methods: This is a cross-sectional, single-center, comparative study. Aqueous humor was aspirated from consecutive senile cataract cases with and without PEX. The levels of urea, creatinine, glucose, calcium, magnesium, phosphate, chlorine, sodium and potassium were measured in the aqueous humor of both groups.

Results: Group-1 included 60 cases without PEX, and Group-2 included 48 cases with PEX. The calcium and chlorine levels were signifi cantly higher in the aqueous humor of the patients with PEX (Group-2) than in the control group (Group-1), whereas the glucose levels were signifi cantly lower in the PEX group than in the control group. The coexistence of nuclear cataracts and PEX in Group-2 was found to be statistically signifi cant.

Conclusion: Between the PEX and non-PEX groups, a difference was found in the levels of the biochemical constituents in the aqueous humor. The changes in biochemical features of aqueous humor may be the cause of ocular morbidity. In the future, the ocular complications can be controlled with medicines that regulate biochemical structure of aqueous humor in patients with PEX. The quantity of aqueous humor obtained from the anterior chamber was very limited and thus, only a small number of parameters could be evaluated. In patients with PEX, further studies are needed to analyze the aqueous humor. Keywords : Pseudoexfoliation, Aqueous Humor, Biochemical Characteristics