title: Mechanical detachment of the anterior hyaloid membrane from the posterior lens capsule.
abstract: OBJECTIVE
  To investigate the incidence of spontaneous detachment of the anterior hyaloid membrane from the posterior lens capsule and to explore the possibility of surgical separation of the anterior hyaloid membrane.
  
  
  METHODS
  Prospective nonrandomized interventional comparative trial and comparative human tissue study.
  
  
  METHODS
  Thirty-eight eyes of 32 patients undergoing primary pars plana vitrectomy combined with cataract extraction and intraocular lens implantation and 3 eye bank eyes for histopathologic examination.
  
  
  METHODS
  The anterior hyaloid membrane and posterior lens capsule were observed with a fiberoptic endoscope. Surgical separation of the anterior hyaloid membrane was attempted by either the hydrodissection method before cataract extraction (18 eyes) or the direct suction method after cataract extraction (20 eyes). In eye bank eyes, histopathologic examination was performed with (one eye) and without (two eyes) surgical separation of the anterior hyaloid membrane.
  
  
  METHODS
  Incidence of spontaneous detachment and success rate of surgical detachment of the anterior hyaloid membrane.
  
  
  RESULTS
  No eye displayed spontaneous detachment of the anterior hyaloid membrane. Using the hydrodissection method, complete detachment of the anterior hyaloid membrane was achieved in 10 eyes (55.6%), partial detachment was attained in 2 eyes (11.1%), and detachment was not induced at all in 6 eyes (33.3%). With the direct suction method, the anterior hyaloid membrane was completely separated from the posterior lens capsule in 10 eyes (50%), partially detached in 10 eyes (50%), and not detached at all in any eye. The direct suction method had a significantly higher success rate than the hydrodissection method (P < 0.001, chi-square test). In eye bank eyes, the surgical manipulation induced complete separation of the anterior hyaloid membrane from the lens capsule.
  
  
  CONCLUSIONS
  Spontaneous detachment of the anterior hyaloid membrane from the posterior lens capsule is very rare. Under endoscopic observation, surgical detachment of the anterior hyaloid membrane was possible in half of the patients.
authors.affiliation: Ukinojo Eye Center, Miyazaki, Japan. Yoshitomi Eye Center, Fukuoka, Japan.
authors.forename: H
authors.initials: H
authors.lastname: Torii
authors.forename: K
authors.initials: K
authors.lastname: Takahashi
authors.forename: F
authors.initials: F
authors.lastname: Yoshitomi
authors.forename: K
authors.initials: K
authors.lastname: Miyata
authors.forename: Y
authors.initials: Y
authors.lastname: Ishii
authors.forename: T
authors.initials: T
authors.lastname: Oshika
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002387:Cataract Extraction; D004724:Endoscopy; D006801:Humans; D015994:Incidence; D007903:Lens Capsule, Crystalline / Q000601:surgery*; D019654:Lens Implantation, Intraocular; D008566:Membranes / Q000601:surgery; D008875:Middle Aged; D013396:Suction; D014821:Vitrectomy / Q000379:methods*; D014822:Vitreous Body / Q000601:surgery*