title: Development of a retrobulbar injection technique for ocular surgery and analgesia in dogs.
abstract: OBJECTIVE
  To develop and compare 3 techniques for retrobulbar injection of local anesthetic agents for ocular surgery and analgesia in dogs.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  17 dogs (including 9 cadavers).
  
  
  METHODS
  Inferior-temporal palpebral (ITP), perimandibular, and combined superior-inferior peribulbar injection techniques were compared by assessing the distribution of latex after injection into the orbits of 5 canine cadavers; magnetic resonance imaging (MRI) evaluation of the distribution of contrast agent after injection in the retrobulbar space of 4 canine cadavers; and assessment of the efficacy and MRI evaluation of the anatomic distribution of injections of a lidocainecontrast agent mixture in 4 anesthetized, nonrecovery dogs. By use of the preferred technique (ITP), the ocular effects of lidocaine anesthesia were evaluated in 4 dogs; during a 2-week period after treatment, dogs underwent ophthalmic examination, Schirmer tear testing (STT), intraocular pressure (IOP) measurement, and Cochet-Bonnet esthesiometry.
  
  
  RESULTS
  Of the 3 techniques, the ITP technique was the preferred method for retrobulbar administration of anesthetic agent in dogs because it was efficacious (pupil dilation and central rotation of the globe achieved in all eyes), easiest to perform, and provided thorough coverage of the intraconal retrobulbar space without complication. During the 2-week follow-up period, the ITP injection did not significantly affect STT, IOP, or Cochet-Bonnet esthesiometry values in dogs.
  
  
  CONCLUSIONS
  In dogs, retrobulbar administration of anesthetic agents via the ITP technique is a potential alternative to systemic administration of neuromuscular blocking agents for ophthalmic surgery and provides the additional benefit of local ocular analgesia.
authors.affiliation: Veterinary Emergency Service, Middleton, WI 53562, USA.
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Accola
authors.forename: Ellison
authors.initials: E
authors.lastname: Bentley
authors.forename: Lesley J
authors.initials: LJ
authors.lastname: Smith
authors.forename: Lisa J
authors.initials: LJ
authors.lastname: Forrest
authors.forename: Cheryl A
authors.initials: CA
authors.lastname: Baumel
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Murphy
mesh_terms: D000698:Analgesia / Q000662:veterinary; D000779:Anesthetics, Local / Q000008:administration & dosage*; D000818:Animals; D002102:Cadaver; D003287:Contrast Media / Q000008:administration & dosage; D004285:Dogs / Q000502:physiology* / Q000601:surgery; D007267:Injections / Q000379:methods / Q000662:veterinary; D007429:Intraocular Pressure; D008012:Lidocaine / Q000008:administration & dosage*; D008279:Magnetic Resonance Imaging / Q000662:veterinary; D009407:Nerve Block / Q000379:methods / Q000662:veterinary*; D003473:Neuromuscular Nondepolarizing Agents / Q000008:administration & dosage; D013508:Ophthalmologic Surgical Procedures / Q000379:methods / Q000662:veterinary*; D009915:Orbit; D011446:Prospective Studies
chemical_list: D000779:Anesthetics, Local; D003287:Contrast Media; D003473:Neuromuscular Nondepolarizing Agents; D008012:Lidocaine