title: Peritubular filtration as cause of severe hypotony after Ahmed valve implantation for glaucoma.
abstract: OBJECTIVE
  To report peritubular filtration as the cause of severe hypotony after Ahmed valve implantation.
  
  
  METHODS
  Interventional case report. In a 65-year-old man with primary open-angle glaucoma, ultrasound biomicroscopy was used to image the peritubular region of his right eye that had severe hypotony during the early postoperative period after an Ahmed valve implantation.
  
  
  RESULTS
  The ultrasound biomicroscopy examination showed peritubular filtration. Additional surgery consisting of tube extraction, closure of the previous insertion opening, reformation of the anterior chamber with viscoelastic, and reintroduction of the tube through a new paracentesis was performed to solve this complication. Twenty-four hours postoperatively, the intraocular pressure increased to 10 mm Hg. During the 6-month follow-up, the mean intraocular pressure was 16.36 mm Hg (standard deviation, 1.45).
  
  
  CONCLUSIONS
  The possibility of peritubular filtration should be considered in eyes with severe hypotony after restrictive valve implantation.
authors.affiliation: Instituto de Investigaciones Oftalmológicas Ramón Castroviejo, Hospital Clínico San Carlos, Universidad Complutense de Madrid, 28003 Madrid, Spain. mherrerad@sego.es
authors.forename: J
authors.initials: J
authors.lastname: García-Feijoó
authors.forename: R
authors.initials: R
authors.lastname: Cuiña-Sardiña
authors.forename: C
authors.initials: C
authors.lastname: Méndez-Fernández
authors.forename: A
authors.initials: A
authors.lastname: Castillo-Gómez
authors.forename: J
authors.initials: J
authors.lastname: García-Sánchez
mesh_terms: D000368:Aged; D000867:Anterior Chamber / Q000000981:diagnostic imaging / Q000378:metabolism / Q000601:surgery; D001082:Aqueous Humor / Q000378:metabolism; D020327:Glaucoma Drainage Implants / Q000009:adverse effects*; D005902:Glaucoma, Open-Angle / Q000601:surgery*; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D015814:Ocular Hypotension / Q000209:etiology*; D019919:Prosthesis Implantation / Q000009:adverse effects; D012086:Reoperation; D014463:Ultrasonography