[Analysis of corneal asphericity in patients after phacoemulsification].

OBJECTIVE: To investigate the distribution of corneal Q-value in the age-related cataract patients and aspherical features of cornea before and after the phacoemulsification (PHACO). METHODS: Thirty-nine eyes of 30 age-related cataract patients in our department were included. Transparent cornea incision at the temporal cornea was applied for patients with cornea astigmatism < 1.00 D and transparent cornea incision at the maximum curvature meridian for patients with cornea astigmatism > or = 1.00 D in PHACO. All patients were followed up to 3 months, corneal Q-value, corneal curvature, astigmatism were examined before and after PHACO, distribution of corneal Q-value and their correlation factors were analyzed. RESULTS: The mean corneal Q-value before and after the PHACO was -0.07 +/- 0.22 and -0.11 +/- 0.16, respectively. There was no statistical difference between the corneal Q-values before and after surgery (t = 1.14, P = 0.26). The mean of corneal curvature before and after the PHACO was (44.6 +/- 1.92) D and (44.70 +/- 1.47) D, respectively. There was no statistical difference between corneal curvature before and after the operation (t = -0.69, P = 0.50). The corneal Q-value was negatively co-related with corneal curvature before the surgery (r = -0.46, P = 0.003). The mean astigmatism power before and after the HACO was (0.67 +/- 0.43) D and (0.66 +/- 0.42) D, respectively. There was no statistical difference between astigmatism power before and after the surgery (t = -0.24, P = 0.82). There was no relationship between the corneal Q-value and astigmatism power before surgery (r = -0.24, P = 0.14). CONCLUSIONS: The corneal Q-value of aged patients is in normal distribution, is negative in the majority, and showed a negative relationship with corneal curvature. There is no statistical difference between the corneal Q-value, corneal curvature, and astigmatism power before and after PHACO surgery.