title: Changes in the optic disc excavation of children affected by cerebral visual impairment: a tomographic analysis.
abstract: OBJECTIVE
  To obtain quantitative data on the optic disc excavation in children affected by cerebral visual impairment (CVI) by using the Heidelberg Retinal Tomograph (HRT)-II (Heidelberg Engineering, Heidelberg, Germany).
  
  
  METHODS
  A total of 24 subjects affected by CVI (mean age, 7.28 years) were examined: 16 in alert conditions and 8 under general anesthesia. The following parameters of the optic nerve head were examined: disc area, cup area, rim area, cup volume, rim volume, cup-to-disc area ratio, mean cup depth, maximum cup depth, cup shape measure, and mean retinal nerve fiber layer (RNFL) thickness. The tomographic results in children with CVI were compared with those of 88 normal, alert subjects of similar age.
  
  
  RESULTS
  The optic disc of patients with CVI appeared smaller than normal. Its excavation, however, was more pronounced. Several tomographic parameters were altered in CVI-affected subjects. Statistical analysis showed a highly significant probability in cup-to-disc area ratio (P < 0.01, both eyes), rim area (P < 0.01, both eyes), cup shape measure (P < 0.01, right eye; P < 0.01, left eye), and mean RNFL thickness (P < 0.01, right eye; P < 0.01, left eye). A novel observation was temporal atrophy of the optic nerve head in CVI.
  
  
  CONCLUSIONS
  The data provide a tridimensional, objective evaluation of the anatomic alterations of the optic nerve head in children with CVI. Furthermore, tomographic standards for optic disc shape in normal children are set for the first time.
authors.affiliation: University Eye Clinic, IRCCS San Matteo Hospital, Pavia, Italy. rubertog@smatteo.pv.it
authors.forename: Giulio
authors.initials: G
authors.lastname: Ruberto
authors.forename: Roberto
authors.initials: R
authors.lastname: Salati
authors.forename: Giovanni
authors.initials: G
authors.lastname: Milano
authors.forename: Chiara
authors.initials: C
authors.lastname: Bertone
authors.forename: Carmine
authors.initials: C
authors.lastname: Tinelli
authors.forename: Elisa
authors.initials: E
authors.lastname: Fazzi
authors.forename: Rosanna
authors.initials: R
authors.lastname: Guagliano
authors.forename: Sabrina
authors.initials: S
authors.lastname: Signorini
authors.forename: Renato
authors.initials: R
authors.lastname: Borgatti
authors.forename: Alessandro
authors.initials: A
authors.lastname: Bianchi
authors.forename: Paolo Emilio
authors.initials: PE
authors.lastname: Bianchi
mesh_terms: D002545:Brain Ischemia / Q000150:complications; D002540:Cerebral Cortex / Q000473:pathology*; D002648:Child; D006801:Humans; D009412:Nerve Fibers / Q000473:pathology; D009887:Ophthalmoscopy / Q000379:methods; D009898:Optic Disk / Q000002:abnormalities*; D009901:Optic Nerve Diseases / Q000175:diagnosis* / Q000209:etiology; D012165:Retinal Ganglion Cells / Q000473:pathology; D012680:Sensitivity and Specificity; D014054:Tomography; D014786:Vision Disorders / Q000175:diagnosis* / Q000209:etiology; D014792:Visual Acuity; D014795:Visual Pathways / Q000473:pathology