title: [Factors affected therapeutic results in treatment of children congenital nasolacrimal duct obstruction by Ritleng lacrimal intubation].
abstract: OBJECTIVE
  To evaluate the efficacy of the Ritleng lacrimal intubation system in the treatment of congenital nasolacrimal duct obstruction (CNLDO) after failed probing and to analyze the effect of various factors that affected the recovery rate.
  
  
  METHODS
  Retrospective noncomparative case series. The outcome of 616 cases (eyes) of silicone intubation with the Ritleng lacrimal intubation system, performed between Feb. 2008 and Oct. 2009 on 546 children with CNLDO (aged from 3 to 156 months with an average at 11 months) from Beijing Children's Hospital, was retrospectively reviewed. The follow-up period varied from 4 to 17 months (average 11 months). The effects of age, treatment history, and the type of obstruction on the recovery rate were evaluated and the complications such as epistaxis, lacrimal duct edema or silicone tube prolapse were recorded. The statistics analysis included Pearson correlation coefficient and independent-samples t-test.
  
  
  RESULTS
  The overall recovery rate was 88% (544/616 cases). In the five sub-groups based on the age, 6 - 12 month, 12 - 24 month, 24 - 36 month, 36 - 48 month and older than 48 month age, the recovery rate was 96% (94/98); 94% (244/260); 87% (104/119); 77% (58/75) and 69% (44/64), respectively (R = -0.98, P = 0.003). According to the times of previous probing, there were three groups, once, twice, and more than twice, the recovery rate was 95% (291/304); 89% (163/184) and 70% (90/128), respectively (R = -0.99, P = 0.050). In the simple membranous obstruction group and the complex obstruction group, the recovery rate was 92% (343/374) and 83% (201/242), respectively (P = 0.000). Complications included laceration of lachrymal point (8 eyes, 1%) and false passage formation (14 eyes, 2%). The silicone tube prolapsed in 18 eyes (3%).
  
  
  CONCLUSIONS
  The Ritleng lacrimal intubation system is an easy, effective and non-traumatic procedure for the treatment of CNLDO children after failed probing. Age of the patients, times of previous probing and type of obstruction influence the recovery rate.
authors.affiliation: National Key Discipline of Pediatrics (Capital Medical University), Ministry of Education, Department of Ophthalmology, Beijing Children's Hospital, Capital Medical University, Beijing 100045, China.
authors.forename: Gang
authors.initials: G
authors.lastname: Yu
authors.forename: Man
authors.initials: M
authors.lastname: Hu
authors.forename: Qian
authors.initials: Q
authors.lastname: Wu
authors.forename: Wen-hong
authors.initials: WH
authors.lastname: Cao
authors.forename: Yun-wei
authors.initials: YW
authors.lastname: Fan
authors.forename: Qi
authors.initials: Q
authors.lastname: Lin
authors.forename: Wen
authors.initials: W
authors.lastname: Liu
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D005124:Eye Abnormalities / Q000628:therapy; D005260:Female; D006801:Humans; D007223:Infant; D007440:Intubation / Q000379:methods*; D007767:Lacrimal Duct Obstruction / Q000151:congenital / Q000628:therapy*; D008297:Male; D009301:Nasolacrimal Duct; D012189:Retrospective Studies; D016896:Treatment Outcome