title: Deep sclerectomy versus trabeculectomy: a morphological study with anterior segment optical coherence tomography.
abstract: OBJECTIVE
  To investigate the intraocular pressure (IOP) lowering mechanisms of deep sclerectomy (DS) with anterior segment optical coherence tomography (AS-OCT).
  
  
  METHODS
  In a prospective cross-sectional study, AS-OCT parameters were compared between DS, trabeculectomy and control cases. Association with IOP and success (IOP≤16 mm Hg without medication) was investigated.
  
  
  RESULTS
  18 DS (15 patients), 17 trabeculectomy (16 patients) and 15 controls (15 patients) were examined. Successful had a taller intrascleral lake (IL) and thicker conjunctival/Tenon's layer (CTL) than non-successful cases (513.3 vs 361.1 µm, p=0.027 and 586.7 vs 251.1 µm, p<0.001, respectively). CTL thickness correlated with IOP (r=-0.6407, p=0.004). CTL thickness was significantly different between controls, DS and trabeculectomy (mean (SD): 203.3 (62.6) vs 418.9 (261.9) vs 604.1 (220.7) µm, p<0.0001). Successful trabeculectomy cases had a taller bleb cavity (BC) than non-successful cases (607.5 vs 176.7 µm, p=0.041). CTL microcysts were detected in 50% of DS and 52.9% of trabeculectomy cases (p=1).
  
  
  CONCLUSIONS
  Trans-conjunctival aqueous percolation was identified as a novel DS drainage route. DS had a fluid reservoir below the scleral flap, the IL, in analogy to the trabeculectomy BC. A postoperative tall IL and a thick CTL were associated with good outcome.
authors.affiliation: Southampton Eye Unit, University Hospital Southampton NHS Foundation Trust, Southampton, UK.
authors.forename: Aris
authors.initials: A
authors.lastname: Konstantopoulos
authors.forename: Mohammad E
authors.initials: ME
authors.lastname: Yadegarfar
authors.forename: Ghasem
authors.initials: G
authors.lastname: Yadegarfar
authors.forename: Alina
authors.initials: A
authors.lastname: Stinghe
authors.forename: Alex
authors.initials: A
authors.lastname: Macleod
authors.forename: Aby
authors.initials: A
authors.lastname: Jacob
authors.forename: Parwez
authors.initials: P
authors.lastname: Hossain
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000869:Anterior Eye Segment / Q000473:pathology / Q000601:surgery; D003228:Conjunctiva / Q000473:pathology / Q000601:surgery; D003430:Cross-Sectional Studies; D004322:Drainage; D005260:Female; D005901:Glaucoma / Q000473:pathology* / Q000601:surgery*; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012590:Sclera / Q000601:surgery*; D013524:Surgical Flaps; D058475:Tenon Capsule / Q000473:pathology / Q000601:surgery; D041623:Tomography, Optical Coherence; D014129:Trabecular Meshwork / Q000601:surgery*; D014130:Trabeculectomy / Q000379:methods*; D016896:Treatment Outcome
keywords: Glaucoma; Imaging