title: Natural course of anterior segment ischemia after disinsertion of extraocular rectus muscles in an animal model.
abstract: OBJECTIVE
  To compare the frequency and severity of anterior segment ischemia (ASI) after disinsertion of extraocular rectus muscles in a rabbit eye model.
  
  
  METHODS
  The rectus muscles of eyes of 84 rabbits were removed. In 42 rabbits one eye underwent three-muscle surgery, whereas the fellow eye underwent two-muscle surgery. In the other 42 rabbits, one eye underwent three-muscle surgery and the fellow eye four-muscle surgery. The surgery included disinsertion together with extirpation of the anterior 10 mm of the muscle. Each eye was examined daily to detect the presence of ASI. Anti-inflammatory eyedrops were not used in any subject. The severity of inflammation and time to complete resolution of inflammatory signs were documented. After inflammation resolved, both eyes of each rabbit were enucleated and studied by a pathologist.
  
  
  RESULTS
  The incidence of ASI was 9.5% in the two-muscle group, 31% in the three-muscle group, and 50% in the four-muscle group (P =0.001). ASI eyes all developed signs on the first postoperative day. Inflammation resolved in 4-38 days. The incidence of ASI increased significantly with the number of muscles operated on. Permanent complications were rare and histopathology results were normal in most cases.
  
  
  CONCLUSIONS
  Inflammation resolved spontaneously in all involved eyes without intervention and only minor clinical or pathologic changes were noted. One eye, however, developed severe sequela but was still preserved. The severity of ASI was directly correlated to the number of operated rectus muscles. Our findings suggest a self-limited nature of ASI in this rabbit model.
authors.affiliation: Ophthalmic Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran. abbasbagheri@yahoo.com
authors.forename: Abbas
authors.initials: A
authors.lastname: Bagheri
authors.forename: Mehdi
authors.initials: M
authors.lastname: Tavakoli
authors.forename: Peiman
authors.initials: P
authors.lastname: Torbati
authors.forename: Maryam
authors.initials: M
authors.lastname: Mirdehghan
authors.forename: Mehdi
authors.initials: M
authors.lastname: Yaseri
authors.forename: Omid
authors.initials: O
authors.lastname: Safarian
authors.forename: Shahin
authors.initials: S
authors.lastname: Yazdani
authors.forename: David
authors.initials: D
authors.lastname: Silbert
mesh_terms: D000818:Animals; D000869:Anterior Eye Segment / Q000098:blood supply*; D004195:Disease Models, Animal; D005128:Eye Diseases / Q000209:etiology*; D007511:Ischemia / Q000209:etiology*; D009801:Oculomotor Muscles / Q000601:surgery*; D013508:Ophthalmologic Surgical Procedures / Q000009:adverse effects* / Q000379:methods; D011183:Postoperative Complications; D011817:Rabbits; D011897:Random Allocation