title: Clinical outcomes after combined Ahmed glaucoma valve implantation and penetrating keratoplasty or pars plana vitrectomy.
abstract: OBJECTIVE
  To evaluate whether a combination of penetrating keratoplasty (PKP) or pars plana vitrectomy (PPV) and Ahmed glaucoma valve (AGV) implantation affords a level of success similar to that of AGV implantation alone.
  
  
  METHODS
  Eighteen eyes underwent simultaneous PPV and AGV, 14 eyes with PKP and AGV and 30 eyes with AGV implantation alone were evaluated. Success was defined as attainment of an intraocular pressure (IOP) >5 and <22 mmHg, with or without use of anti-glaucoma medication. Kaplan-Meier survival analysis was performed to compare cumulative survival between the combined surgery groups and the AGV implantation-alone group. Cox proportional hazard regression analysis was conducted to identify factors predictive of success in each of the three groups.
  
  
  RESULTS
  Mean (±standard deviation) preoperative IOP was 30.2 ± 10.2 mmHg in the PKP + AGV, 35.2 ± 9.8 mmHg in the PPV + AGV, and 36.2 ± 10.1 mmHg in the AGV implantation-alone group. The cumulative success rate at 18 months was 66.9%, 73.2%, and 70.8% in the three groups, respectively. Neither combined surgery group differed significantly in terms of cumulative success rate compared with the AGV implantation-alone group (p = 0.556, p = 0.487, respectively). The mean number of preoperative anti-glaucoma medications prescribed was significantly associated with success in the PKP + AGV implantation group (hazard ratio, 2.942; p = 0.024).
  
  
  CONCLUSIONS
  Either PKP or PPV performed in conjunction with AGV implantation afforded similar success rates compared to patients treated with AGV implantation alone. Therefore, in patients with refractory glaucoma who have underlying corneal or retinal pathology requiring treatment with PKP or PPV, AGV implantation can be performed simultaneously.
authors.affiliation: Department of Ophthalmology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
authors.forename: Jin Young
authors.initials: JY
authors.lastname: Lee
authors.forename: Kyung Rim
authors.initials: KR
authors.lastname: Sung
authors.forename: Hung Won
authors.initials: HW
authors.lastname: Tchah
authors.forename: Young Hee
authors.initials: YH
authors.lastname: Yoon
authors.forename: June Gone
authors.initials: JG
authors.lastname: Kim
authors.forename: Myoung Joon
authors.initials: MJ
authors.lastname: Kim
authors.forename: Jae Yong
authors.initials: JY
authors.lastname: Kim
authors.forename: Sung-Cheol
authors.initials: SC
authors.lastname: Yun
authors.forename: Joo Yong
authors.initials: JY
authors.lastname: Lee
mesh_terms: D005260:Female; D005500:Follow-Up Studies; D005901:Glaucoma / Q000503:physiopathology / Q000601:surgery*; D020327:Glaucoma Drainage Implants; D006801:Humans; D007429:Intraocular Pressure; D015948:Keratoplasty, Penetrating / Q000379:methods*; D008297:Male; D008875:Middle Aged; D019919:Prosthesis Implantation / Q000379:methods*; D012189:Retrospective Studies; D014065:Tonometry, Ocular; D016896:Treatment Outcome; D014821:Vitrectomy / Q000379:methods*