title: Filtering bleb structure associated with long-term intraocular pressure control after amniotic membrane-assisted trabeculectomy.
abstract: OBJECTIVE
  To determine whether amniotic membrane transplantation (AMT) at trabeculectomy affects intrableb structures and which intrableb parameters are significantly correlated with the long-term intraocular pressure (IOP) control.
  
  
  METHODS
  Enrolled were 64 eyes of 56 glaucoma patients who underwent trabeculectomy without (36 eyes) or with (28 eyes) AMT. Bleb structure was evaluated by ultrasound biomicroscopy (UBM) at least one year after surgery. IOP control was defined as good when the eyes had a more than 30% decrease in the preoperative IOP and an IOP value <18 mmHg if the preoperative IOP was higher than 21 mmHg. Logistic regression analyses were conducted to identify factors significantly associated with IOP control.
  
  
  RESULTS
  Intervals between surgery and the timing of the UBM examinations (median; 2.5 years) and the overall frequency of good IOP control (28/36 in the eyes without AMT and 17/28 in those with AMT; chi-square test, P = 0.2276) were similar in the two groups. The eyes with AMT had a significantly lower number of type H (high reflective) or L (low reflective) blebs and a higher number of type E (encapsulated) blebs compared to those without AMT (P < 0.0001). Among independent variables, which included age, sex, glaucoma type, lens status, the number of ocular hypotensives, and previous intraocular surgeries, only type F (flattened) bleb in eyes without AMT (P = 0.0008, odds ratio [OR] = 0.0256) and no or limited intrableb fluid-filled space in eyes with AMT were significantly associated with poor IOP control (P = 0.0026, OR = 0.0111, and 0.0071, 0.0167, respectively).
  
  
  CONCLUSIONS
  Intrableb structures after trabeculectomy alone versus AMT-assisted trabeculectomy were distinct. The bleb wall reflectivity in the former and the extent of the subconjunctival fluid-filled space in the latter were factors associated with long-term IOP control.
authors.affiliation: Division of Ophthalmology, Department of Surgery, Kobe University Graduate School of Medicine, Kusunoki-cho, Chuo-ku, Kobe, Japan. manakamu@med.kobe-u.ac.jp
authors.forename: Makoto
authors.initials: M
authors.lastname: Nakamura
authors.forename: Maiko
authors.initials: M
authors.lastname: Naka
authors.forename: Yasuko
authors.initials: Y
authors.lastname: Tatsumi
authors.forename: Azusa
authors.initials: A
authors.lastname: Nagai-Kusuhara
authors.forename: Akiyasu
authors.initials: A
authors.lastname: Kanamori
authors.forename: Yuko
authors.initials: Y
authors.lastname: Yamada
authors.forename: Akira
authors.initials: A
authors.lastname: Negi
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000650:Amnion / Q000637:transplantation*; D000869:Anterior Eye Segment / Q000473:pathology*; D001684:Biological Dressings; D005260:Female; D005901:Glaucoma / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D008297:Male; D033401:Microscopy, Acoustic; D008875:Middle Aged; D012189:Retrospective Studies; D012590:Sclera / Q000473:pathology*; D013524:Surgical Flaps / Q000473:pathology; D014130:Trabeculectomy / Q000379:methods*; D055815:Young Adult