title: Different modes of intraocular pressure reduction after three different nonfiltering surgeries and trabeculectomy.
abstract: OBJECTIVE
  To study the mode of intraocular pressure (IOP) reduction based on correlation with the preoperative IOP after filtering and nonfiltering surgeries.
  
  
  METHODS
  Pre- and postsurgical IOPs at 6 months were compared in one eye of each of 789 subjects with primary open-angle glaucoma, pseudoexfoliation glaucoma, or ocular hypertension who underwent trabeculectomy with adjunctive mitomycin C alone (Lectomy-MMC) (n = 145), phaco-viscocanalostomy (Phaco-VCS) (n = 320), phaco-trabeculotomy ab externo (Phaco-lotomy) (n = 116), or phacoemulsification aspiration and intraocular lens implantation alone (PEA+IOL) (n = 208).
  
  
  RESULTS
  The correlation between the preoperative and 6-month postoperative IOP was not significant in eyes that underwent Lectomy MMC (r = -0.026, P = 0.7552, IOP reduction 51.9%), but was significant in eyes treated by Phaco-VCS (r = 0.409; IOP reduction, 24.8%) or PEA+IOL alone (r = 0.294; IOP reduction, 9.9%), and was marginal in eyes treated by Phaco-lotomy (P = 0.062; r = 0.174; IOP reduction, 24.1%). Among the four cohorts studied, the variation in the 6-month postoperative IOP was the largest after Lectomy-MMC.
  
  
  CONCLUSIONS
  After glaucoma surgery, there are two modes of IOP reduction. The postoperative IOP after Lectomy MMC did not correlate with the preoperative IOP, whereas the postoperative IOP levels after Phaco-VCS, Phaco-Lotomy, and PEA+IOL correlated with preoperative IOP levels. We may be able to predict postsurgical IOP after nonfiltering surgery.
authors.affiliation: Sensho-kai Eye Institute, Kyoto, Japan. chihara-oph@umin.net
authors.forename: Etsuo
authors.initials: E
authors.lastname: Chihara
authors.forename: Ken
authors.initials: K
authors.lastname: Hayashi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D017889:Exfoliation Syndrome / Q000503:physiopathology / Q000601:surgery*; D005902:Glaucoma, Open-Angle / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007429:Intraocular Pressure; D008875:Middle Aged; D016685:Mitomycin / Q000627:therapeutic use; D009798:Ocular Hypertension / Q000503:physiopathology / Q000601:surgery*; D018918:Phacoemulsification; D011184:Postoperative Period; D012189:Retrospective Studies; D014130:Trabeculectomy / Q000379:methods
chemical_list: D016685:Mitomycin