title: Comparison of bleb morphology between trabeculectomy and deep sclerectomy using a clinical grading scale and anterior segment optical coherence tomography.
abstract: OBJECTIVE
  The role of the filtration bleb for IOP management following trabeculectomy (TRAB) and deep sclerectomy (DS) in glaucoma is highlighted in this study.
  
  
  BACKGROUND
  This study serves to analyse the bleb morphology and IOP using the Indiana Bleb Appearance Grading Scale (IBAGS) and the anterior-segment optical coherence tomography (AS-OCT) postoperatively and at 3 months.
  
  
  METHODS
  The retrospective study was performed by a single surgeon.
  
  
  METHODS
  Twenty-eight patients with open-angle glaucoma were recruited into the study, 14 in each of the TRAB (fornix) and DS groups.
  
  
  METHODS
  The surgical intervention was dependent on the irido-corneal angle configuration on gonioscopy.
  
  
  METHODS
  Pre-operatively, we collected visual acuity, medications and IOP. Three months postoperatively, we used the IBAGS to assess bleb morphology, including bleb height, extent, vascularity and leak. AS-OCT was also used to assess bleb height, thickness, cyst presence and posterior and intrascleral fluid.
  
  
  RESULTS
  Central corneal thickness and mean IOP at 3 months postoperatively were significantly lower in the TRAB group (7.75 vs. 12.27 mmHg; P = 0.005). Blebs that were significantly higher, broader and less vascular compared with DS were displayed by TRAB eyes. The AS-OCT measurements confirmed TRAB eyes had significantly higher blebs and increased intrascleral fluid compared with DS eyes.
  
  
  CONCLUSIONS
  Significant differences in bleb morphology, correlating with improved IOP outcomes in TRAB eyes compared with DS eyes in patients with open-angle glaucoma, were showed by both the IBAGS and AS-OCT. Despite the limitations of each classification system, a higher bleb with an increased aqueous reservoir is associated with optimal IOP results.
authors.affiliation: Ophthalmology Department, Royal North Shore Hospital, Sydney, New South Wales, Australia.|Glaucoma Unit, Sydney Eye Hospital, Sydney, New South Wales, Australia.
authors.forename: Lawrence J
authors.identifier: http://orcid.org/0000-0002-3548-2148
authors.initials: LJ
authors.lastname: Oh
authors.affiliation: ENT Department, Royal North Shore Hospital, Sydney, New South Wales, Australia.
authors.forename: Eugene
authors.initials: E
authors.lastname: Wong
authors.affiliation: Coastwide Eye Surgery, Erina and Wyong, New South Wales, Australia.
authors.forename: Julie
authors.initials: J
authors.lastname: Lam
authors.affiliation: Coastwide Eye Surgery, Erina and Wyong, New South Wales, Australia.|Eye Associates, Sydney, New South Wales, Australia.|Glaucoma Unit, Sydney Eye Hospital, Sydney, New South Wales, Australia.
authors.forename: Colin I
authors.identifier: http://orcid.org/0000-0003-1484-2615
authors.initials: CI
authors.lastname: Clement
mesh_terms: D000368:Aged; D000869:Anterior Eye Segment / Q000473:pathology* / Q000601:surgery; D005260:Female; D005902:Glaucoma, Open-Angle / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D012189:Retrospective Studies; D012599:Sclerostomy / Q000379:methods*; D019738:Surgically-Created Structures; D041623:Tomography, Optical Coherence / Q000379:methods; D014065:Tonometry, Ocular; D014130:Trabeculectomy / Q000379:methods*
keywords: filtering blebs; glaucoma; trabeculectomy