title: Liquid nitrogen cryotherapy for surface eye disease (an AOS thesis).
abstract: OBJECTIVE
  To evaluate the effects of new treatments with liquid nitrogen cryotherapy on some external eye conditions.
  
  
  METHODS
  In this retrospective case study, 6 separate series from a single tertiary care referral center practice are described. Liquid nitrogen cryotherapy was used to treat conjunctival amyloidosis, primary pterygia, recurrent pterygia, advancing wavelike epitheliopathy (AWLE), superior limbic keratoconjunctivitis (SLK), and palpebral vernal keratoconjunctivitis (VKC). The main outcome measure was the resolution of the disease process after treatment.
  
  
  RESULTS
  Four patients with primary localized conjunctival amyloidosis were treated with liquid nitrogen cryotherapy. Two of them had recurrence of the amyloidosis, which cleared with subsequent treatment. Eighteen patients with primary pterygia had excision and cryotherapy with 1 recurrence. Of 6 subjects who presented with recurrent pterygia, 4 had a second recurrence after excision and cryotherapy. In 5 patients with AWLE, the condition resolved within 2 weeks without recurrence or the need for subsequent cryotherapy. Four patients with SLK were treated with liquid nitrogen cryotherapy. Disease recurred in 2 patients and 3 of 7 eyes, although subsequent cryotherapy eradicated SLK in all cases. Two patients and 3 eyelids with palpebral VKC were treated with liquid nitrogen cryotherapy. VKC recurred in all cases.
  
  
  CONCLUSIONS
  Liquid nitrogen cryotherapy to the surface of the eye is effective in treating AWLE, and SLK. Excision followed by cryotherapy is successful in treating conjunctival amyloidosis and primary pterygia Liquid nitrogen cryotherapy is unsuccessful in the treatment of recurrent pterygia and VKC.
authors.affiliation: Department of Ophthalmology (Casey Eye Institute), Oregon Health & Science University, Portland, Oregon, USA.
authors.forename: Frederick Web
authors.initials: FW
authors.lastname: Fraunfelder
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000686:Amyloidosis / Q000628:therapy*; D002648:Child; D003229:Conjunctival Diseases / Q000628:therapy*; D003316:Corneal Diseases / Q000628:therapy*; D017679:Cryotherapy / Q000379:methods*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007637:Keratoconjunctivitis / Q000628:therapy*; D008297:Male; D008875:Middle Aged; D009584:Nitrogen; D011625:Pterygium / Q000628:therapy*; D012008:Recurrence; D012189:Retrospective Studies; D016896:Treatment Outcome
chemical_list: D009584:Nitrogen