title: Previous cyclodestruction is a risk factor for late-onset hypotony and suprachoroidal haemorrhage after glaucoma drainage device surgery.
abstract: OBJECTIVE
  To investigate whether previous cyclodestructive (eg, cyclophotocoagulation and cyclocryodestruction) procedures have any influence on the general outcome and pressure level after glaucoma drainage device (GDD) surgery.
  
  
  METHODS
  Retrospective analysis of 110 consecutive patients who had undergone GDD (Baerveldt 250 mm(2) and 350 mm(2) implant, AMO, USA) surgery with a minimum follow-up of 3 months. The patients were divided into patients with previous cyclodestructive surgery before GDD surgery (I; 47 patients) and patients without previous cyclodestructive surgery (II; 63 patients). Intraocular pressure (IOP), medication score, best-corrected visual acuity and surgical treatments were recorded before and after drainage device implantation.
  
  
  RESULTS
  Patients of group I had a mean preoperative IOP of 32.1 mm Hg and a mean medication score of 4.8; patients of group II had a mean preoperative IOP of 29.2 mm Hg (p=0.18) and a mean medication score of 4.9 (p=0.84). All patients who developed suprachoroidal haemorrhage (six cases) belonged to group I (6/47=12.8%), no patient of group II (0/63=0%) developed suprachoroidal haemorrhage (Fisher's test: p=0.01). Twelve patients developed late-onset (>6 weeks after GDD surgery) hypotony, nine of them belonging to group I (9/47=19.1%) and three of them to group II (3/63=4.8%) (Fisher's test: p=0.03).
  
  
  CONCLUSIONS
  While taking potential bias arising from the retrospective nature of the study into consideration, a history of previous cyclodestructive procedures before GDD surgery seems to be a major risk factor for suprachoroidal haemorrhage and for late-onset postoperative hypotony.
authors.affiliation: Center of Ophthalmology, University of Cologne, Joseph-Stelzmann-Strasse 9, Cologne, Germany. andre.rosentreter@googlemail.com
authors.forename: André
authors.initials: A
authors.lastname: Rosentreter
authors.forename: Stergiani
authors.initials: S
authors.lastname: Gaki
authors.forename: Alexandra
authors.initials: A
authors.lastname: Lappas
authors.forename: Claus
authors.initials: C
authors.lastname: Cursiefen
authors.forename: Thomas S
authors.initials: TS
authors.lastname: Dietlein
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D002832:Choroid Hemorrhage / Q000453:epidemiology* / Q000473:pathology; D017679:Cryotherapy / Q000009:adverse effects*; D005260:Female; D005500:Follow-Up Studies; D005901:Glaucoma / Q000601:surgery*; D020327:Glaucoma Drainage Implants / Q000009:adverse effects*; D006801:Humans; D007429:Intraocular Pressure; D008028:Light Coagulation / Q000009:adverse effects*; D008297:Male; D008875:Middle Aged; D015814:Ocular Hypotension / Q000453:epidemiology* / Q000473:pathology; D011183:Postoperative Complications / Q000453:epidemiology / Q000473:pathology; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome; D014792:Visual Acuity; D055815:Young Adult
keywords: Aqueous humour; Glaucoma; Intraocular pressure; Treatment Lasers; Treatment Surgery