title: Idiopathic phacodonesis in senile cataract patients in Qinghai, China.
abstract: OBJECTIVE
  To investigate the frequency of idiopathic phacodonesis (IP) in senile cataract subjects and the short-term clinical outcomes following cataract surgery.
  
  
  METHODS
  This institutional case-control study included 1301 consecutive low-income cataract subjects from June to November 2009. Anterior segment were carefully evaluated with dilated pupil under slit-lamp. IP were screened and graded by a criteria set by the authors. Risk factors, surgical outcomes, and operative complications were analyzed.
  
  
  RESULTS
  A total of 42 subjects (3.2%) with IP were diagnosed and classified as grade 1 (36 subjects), grade 2 (5 subjects) and grade 3 (1 subject). Harder lenses and intumescent cataracts were observed in the IP group than the control group (P<0.05). Logistics regression test also indicated the main risk factor was the hardness of the lens. The incidence of zonular dialysis during surgery was 23.8% (10 eyes), which was significantly higher than the controls (0.7%, P<0.001). Visual outcomes of the two groups were not statistically or clinically significant.
  
  
  CONCLUSIONS
  Hard nucleus and intumescent cataract are related to IP in senile cataract subjects in Qinghai, China. With more care being taken, grade 1 and some of the grade 2 IP subjects achieved similar surgical outcomes as compared to controls.
authors.affiliation: Department of Ophthalmology, Peking Union Medical College Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Beijing 100730, China.
authors.forename: Xiao-Wei
authors.initials: XW
authors.lastname: Liu
authors.forename: Zheng
authors.initials: Z
authors.lastname: Wang
authors.forename: Wei-Hong
authors.initials: WH
authors.lastname: Yu
authors.forename: Zao-Wen
authors.initials: ZW
authors.lastname: Wang
authors.forename: Yan-Ning
authors.initials: YN
authors.lastname: Zhang
authors.forename: Jian-Jun
authors.initials: JJ
authors.lastname: Liu
authors.forename: Rui-Fang
authors.initials: RF
authors.lastname: Sui