title: [Analysis of corneal asphericity in patients after phacoemulsification].
abstract: 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.
authors.affiliation: Department of Ophthalmology, Guangdong Province Hospital of Integrated Traditional and Western Medicine, Foshan 528200, China.
authors.forename: Hai-wu
authors.initials: HW
authors.lastname: Li
authors.forename: Hai-ke
authors.initials: HK
authors.lastname: Guo
authors.forename: Hong-yang
authors.initials: HY
authors.lastname: Zhang
authors.forename: Mei-ying
authors.initials: MY
authors.lastname: Liu
mesh_terms: D000368:Aged; D002386:Cataract / Q000503:physiopathology* / Q000628:therapy; D003315:Cornea / Q000503:physiopathology* / Q000601:surgery; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D018918:Phacoemulsification / Q000379:methods*; D011446:Prospective Studies; D012029:Refraction, Ocular; D014792:Visual Acuity