title: Fluorophotometric and tonometric evaluation of ocular effects following aqueocentesis performed with needles of various sizes in dogs.
abstract: OBJECTIVE
  To measure ocular effects (blood-aqueous barrier breakdown and intraocular pressure [IOP]) following aqueocentesis performed with needles of various sizes in dogs.
  
  
  METHODS
  28 healthy adult dogs.
  
  
  METHODS
  24 dogs underwent unilateral aqueocentesis (24 treated eyes and 24 contra-lateral untreated eyes); 25-, 27-, or 30-gauge needles were used in 3 treatment groups (n = 8/group). Four dogs were untreated controls. Aqueocentesis was performed during sedation and topical anesthesia. Anterior chamber fluorophotometry was performed before and after aqueocentesis on day 1. On days 2 through 5, sedation and fluorophotometry were repeated. Intraocular pressure was measured with a rebound tonometer at multiple time points.
  
  
  RESULTS
  Aqueocentesis resulted in blood-aqueous barrier breakdown detected via fluorophotometry in all treated eyes, with barrier reestablishment by day 5. On day 2, the contralateral untreated eyes of all 3 groups also had significantly increased fluorescence. Use of a 25-gauge needle resulted in a significant increase in treated eyes' anterior chamber fluorescence on days 3 and 5 as well as a significant increase in IOP 20 minutes following aqueocentesis, compared with the other treatment groups.
  
  
  CONCLUSIONS
  Aqueocentesis performed with a 25-gauge needle resulted in the greatest degree of blood-aqueous barrier breakdown and a brief state of intraocular hypertension. Use of a 27- or 30-gauge needle is recommended for aqueous paracentesis. A consensual ocular reaction appeared to occur in dogs following unilateral traumatic blood-aqueous barrier breakdown and may be of clinical importance.
authors: Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Kansas State University, Manhattan, KS 66506, USA. rachelallbaugh@yahoo.com
authors: Rachel A
authors: RA
authors: Allbaugh
authors: James K
authors: JK
authors: Roush
authors: Amy J
authors: AJ
authors: Rankin
authors: Harriet J
authors: HJ
authors: Davidson
mesh_terms: D000818:Animals; D000867:Anterior Chamber / Q000293:injuries; D018916:Blood-Aqueous Barrier / Q000293:injuries; D004285:Dogs / Q000293:injuries* / Q000502:physiology; D005260:Female; D015590:Fluorophotometry / Q000379:methods / Q000662:veterinary*; D007429:Intraocular Pressure; D008297:Male; D009339:Needles / Q000009:adverse effects / Q000662:veterinary*; D019152:Paracentesis / Q000295:instrumentation / Q000662:veterinary*; D014065:Tonometry, Ocular / Q000379:methods / Q000662:veterinary*