title: Changes in the micromorphology of the corneal subbasal nerve plexus in patients after plaque brachytherapy.
abstract: BACKGROUND
  To quantify the development of radiation neuropathy in corneal subbasal nerve plexus (SNP) after plaque brachytherapy, and the subsequent regeneration of SNP micromorphology and corneal sensation.
  
  
  METHODS
  Nine eyes of 9 melanoma patients (ciliary body: 3, iris: 2, conjunctiva: 4) underwent brachytherapy (ruthenium-106 plaque, dose to tumour base: 523 ± 231 Gy). SNP micromorphology was assessed by in-vivo confocal microscopy. Using software developed in-house, pre-irradiation findings were compared with those obtained after 3 days, 1, 4 and 7 months, and related to radiation dose and corneal sensation.
  
  
  RESULTS
  After 3 days nerve fibres were absent from the applicator zone and central cornea, and corneal sensation was abolished. The earliest regenerating fibres were seen at the one-month follow-up. By 4 months SNP structures had increased to one-third of pre-treatment status (based on nerve fibre density and nerve fibre count), and corneal sensation had returned to approximately two-thirds of pre-irradiation values. Regeneration of SNP and corneal sensation was nearly complete 7 months after plaque brachytherapy.
  
  
  CONCLUSIONS
  The evaluation of SNP micromorphology and corneal sensation is a reliable and clinically useful method for assessing neuropathy after plaque brachytherapy. Radiation-induced neuropathy of corneal nerves develops quickly and is partly reversible within 7 months. The clinical impact of radiation-induced SNP damage is moderate.
authors.forename: Andrey
authors.initials: A
authors.lastname: Zhivov
authors.forename: Karsten
authors.initials: K
authors.lastname: Winter
authors.forename: Sabine
authors.initials: S
authors.lastname: Peschel
authors.forename: Oliver
authors.initials: O
authors.lastname: Stachs
authors.forename: Andreas
authors.initials: A
authors.lastname: Wree
authors.forename: Guido
authors.initials: G
authors.lastname: Hildebrandt
authors.forename: Rudolf
authors.initials: R
authors.lastname: Guthoff
mesh_terms: D000328:Adult; D000368:Aged; D001918:Brachytherapy / Q000009:adverse effects*; D003315:Cornea / Q000528:radiation effects; D005134:Eye Neoplasms / Q000532:radiotherapy*; D005260:Female; D006801:Humans; D008297:Male; D008545:Melanoma / Q000532:radiotherapy*; D018613:Microscopy, Confocal; D008875:Middle Aged; D009410:Nerve Degeneration / Q000209:etiology* / Q000473:pathology; D009412:Nerve Fibers / Q000473:pathology / Q000528:radiation effects; D010523:Peripheral Nervous System Diseases / Q000209:etiology / Q000473:pathology; D011832:Radiation Injuries / Q000473:pathology*; D012429:Ruthenium Radioisotopes / Q000009:adverse effects; D012677:Sensation / Q000528:radiation effects
chemical_list: D012429:Ruthenium Radioisotopes