title: Treatment of severe keratoconjunctivitis sicca by parotid duct transposition after tympanic neurectomy in rabbits.
abstract: OBJECTIVE
  To investigate the feasibility of parotid duct transposition after tympanic neurectomy to treat severe keratoconjunctivitis sicca (KCS) in rabbits.
  
  
  METHODS
  Thirty rabbits were divided into three groups in experiment 1. One eye was operated on, and the contralateral eye served as the control. In the KCS group, the lacrimal gland, harderian gland, and nictitating membrane were removed. In the group with parotid duct transposition (DT), the parotid duct was transposed into the lower conjunctival fornix. In the group with parotid duct transposition after tympanic neurectomy (DTTN), the tympanic nerve was resected in addition to parotid duct transposition. Schirmer test was performed and density of corneal staining was determined monthly after surgery, and goblet cell density was measured at postoperative month 3. In experiment 2, the tympanic nerve was resected on one side in 12 rabbits. Both sides of the parotid gland were resected for histopathology at intervals of 2 months to 1 year after surgery.
  
  
  RESULTS
  Tear secretion from operated eyes at rest increased significantly after surgery in the treatment groups compared with the KCS group. Tear secretion from operated eyes after chewing was significantly lower in the DTTN than in the DT group. The corneal staining scores were higher in the operated than in the control eyes of the three groups, without significant difference among the operated eyes. Parotid gland atrophy on the operated side occurred at postoperative month 4 and recovered to normal 1 year after surgery.
  
  
  CONCLUSIONS
  Parotid duct transposition after tympanic neurectomy could effectively reduce gustatory epiphora but may be insufficient to promote ocular surface health.
authors.affiliation: Department of Oral and Maxillofacial Surgery, Peking University School and Hospital of Stomatology, Beijing, China.
authors.forename: Zhi-yuan
authors.initials: ZY
authors.lastname: Chen
authors.forename: Ying
authors.initials: Y
authors.lastname: Jie
authors.forename: Guang-yan
authors.initials: GY
authors.lastname: Yu
mesh_terms: D000681:Amylases / Q000378:metabolism; D000818:Animals; D002452:Cell Count; D002814:Chorda Tympani Nerve / Q000601:surgery*; D003714:Denervation; D005240:Feasibility Studies; D005260:Female; D019793:Fluorescein; D020397:Goblet Cells / Q000166:cytology; D006243:Harderian Gland / Q000601:surgery; D007638:Keratoconjunctivitis Sicca / Q000378:metabolism / Q000601:surgery*; D007765:Lacrimal Apparatus / Q000601:surgery; D008297:Male; D009541:Nictitating Membrane / Q000601:surgery; D010306:Parotid Gland / Q000294:innervation / Q000637:transplantation*; D011817:Rabbits; D012395:Rose Bengal; D013666:Tears / Q000201:enzymology / Q000378:metabolism
chemical_list: D012395:Rose Bengal; D000681:Amylases; D019793:Fluorescein