title: Daytime fluctuation of intraocular pressure in patients with primary angle-closure glaucoma after trabeculectomy.
abstract: OBJECTIVE
  To evaluate the daytime fluctuation of intraocular pressure (IOP) in patients with primary angle-closure glaucoma (PACG) after trabeculectomy.
  
  
  METHODS
  A total of 176 patients with PACG participated in a clinical trial of trabeculectomy with or without releasable sutures. Applanation IOP was measured at 5, 7, and 10 AM, and 2, 6, and 10 PM at 3 months posttrabeculectomy. We documented the mean, peak, and trough IOPs, determined the fluctuation of daytime IOP, and explored the associations of IOP fluctuation with baseline factors.
  
  
  RESULTS
  IOP measurements were obtained in 173 patients. The mean daytime IOP was 13.2±3.7 mm Hg; mean peak IOP 15.1±4.1 mm Hg, mean trough IOP 11.3±3.5 mm Hg, and mean fluctuation 3.8±2.1 mm Hg. Fluctuation was positively correlated with peak (r=0.528, R2=0.28, P<0.001) and mean IOP (r=0.278, R2=0.08, P<0.001), but not with the trough IOP (r=0.015, P=0.843). Fluctuation was lower with extent of bleb (0.6 mm Hg/unit increase in extent; 95% CI, 0.1-1.2 mm Hg) and in blebs with microcysts (1.1 mm Hg less fluctuation; 95% CI, 0.2-1.9 mm Hg). Fluctuation was not associated with sex, age, baseline IOP, extent of peripheral anterior synechia or number of glaucoma medications before surgery, mean deviation of the visual field, vertical cup:disc ratio, or the use of releasable sutures.
  
  
  CONCLUSIONS
  The mean fluctuation of daytime IOP after trabeculectomy for PACG was about 4 mm Hg. The fluctuation was positively associated with higher peak and mean IOP and negatively associated with extent of bleb and presence of microcysts.
authors.affiliation: Beijing Tongren Eye Center, Beijing Tongren Hospital, Beijing Ophthalmology & Visual Science Key Lab, Capital Medical University, Beijing, China.
authors.forename: Yuan Bo
authors.initials: YB
authors.lastname: Liang
authors.forename: Cong
authors.initials: C
authors.lastname: Xie
authors.forename: Hai Lin
authors.initials: HL
authors.lastname: Meng
authors.forename: Mei Yan
authors.initials: MY
authors.lastname: Feng
authors.forename: Su Jie
authors.initials: SJ
authors.lastname: Fan
authors.forename: Luo Ru
authors.initials: LR
authors.lastname: Liu
authors.forename: Li Lian
authors.initials: LL
authors.lastname: Xie
authors.forename: Jia
authors.initials: J
authors.lastname: Chao
authors.forename: Xing
authors.initials: X
authors.lastname: Wang
authors.forename: Ning Li
authors.initials: NL
authors.lastname: Wang
authors.forename: Ravi
authors.initials: R
authors.lastname: Thomas
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000503:physiopathology* / Q000601:surgery*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D017440:Photoperiod; D013536:Suture Techniques; D014065:Tonometry, Ocular; D014130:Trabeculectomy; D014794:Visual Fields / Q000502:physiology