title: Management of increased vitreous pressure during penetrating keratoplasty using pars plana anterior vitreous aspiration.
abstract: OBJECTIVE
  To describe the technique, outcomes, and complication rates for a method of pars plana vitreous aspiration to control excessive vitreous pressure during penetrating keratoplasty.
  
  
  METHODS
  All cases of penetrating keratoplasty were reviewed retrospectively in a large cornea subspecialty private practice over a 5-year period, and 70 cases of penetrating keratoplasty complicated by excessive posterior pressure were identified. Study eyes were treated with a pars plana vitreous aspiration technique to relieve excessive posterior vitreous pressure. The main study parameters included preoperative best corrected visual acuity (BCVA), postoperative BCVA at the last recorded follow-up visit, refractive cylinder at 1 year, complications related to surgery, and other conditions that may have influenced visual function. The mean follow-up period was 24.5 months with a range of 1 to 61.1 months.
  
  
  RESULTS
  Adverse outcomes during the extended period of follow-up included rejection in 11 of 70 eyes, graft failure in 7 of 70 eyes, glaucoma in 4 of 70 eyes, and postoperative cystoid macular edema (CME) in 5 of 70 eyes. Posterior capsulotomies using the neodymium-yttrium aluminum garnet laser were necessary in 10 of 70 patients during the follow-up period. The average magnitude of refractive astigmatism at 1 year after surgery was 3.73 diopters (D) with a range of 0 to 8 D. There were no known retinal complications other than CME and no complications that could be directly attributed to the pars plana vitreous aspiration technique.
  
  
  CONCLUSIONS
  Pars plana anterior vitreous aspiration is a safe and effective technique for controlling increased vitreous pressure, which can complicate penetrating keratoplasty.
authors.affiliation: Shaw Eye Center, Phoenix, Arizona 85006, USA.
authors.forename: R H
authors.initials: RH
authors.lastname: Gross
authors.forename: E L
authors.initials: EL
authors.lastname: Shaw
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000869:Anterior Eye Segment / Q000601:surgery*; D004322:Drainage / Q000379:methods*; D005128:Eye Diseases / Q000209:etiology / Q000601:surgery*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015948:Keratoplasty, Penetrating / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D013508:Ophthalmologic Surgical Procedures; D011183:Postoperative Complications; D011312:Pressure; D012189:Retrospective Studies; D016896:Treatment Outcome; D014792:Visual Acuity; D014822:Vitreous Body / Q000473:pathology / Q000601:surgery*