title: The structure and function of the macula in patients with advanced retinitis pigmentosa.
abstract: OBJECTIVE
  To assess the structure and function of the macula in advanced retinitis pigmentosa (RP).
  
  
  METHODS
  Twenty-nine eyes of 22 patients with RP were compared against 17 control eyes. Time-domain optical coherence tomography (OCT) data were processed using OCTRIMA (optical coherence tomography retinal image analysis) as a means of quantifying commercial OCT system images. The thickness of the retinal nerve fiber layer (RNFL), ganglion cell layer and inner plexiform layer complex (GCL+IPL), inner nuclear layer and outer plexiform layer complex (INL+OPL), and the outer nuclear layer (ONL) were measured. Multifocal electroretinography (mfERG) was performed; two groups were formed based on the mfERG findings. Fourteen eyes had no detectable central retinal function (NCRF) on mfERG; detectable but abnormal retinal function (DRF) was present in the mfERG of the other 15 eyes.
  
  
  RESULTS
  The thickness of the ONL in the central macular region was significantly less in the NCRF eyes compared with that in both DRF eyes and controls. The ONL was significantly thinner in the pericentral region in both patient groups compared with that in controls, whereas the thickness of the GCL+IPL and INL+OPL was significantly decreased only in the NCRF eyes. The RNFL in the peripheral region was significantly thicker, whereas the thickness of the GCL+IPL and ONL was significantly thinner in both patient groups compared with that in controls.
  
  
  CONCLUSIONS
  The results are consistent with degeneration of the outer retina preceding inner retinal changes in RP. OCT image segmentation enables objective evaluation of retinal structural changes in RP, with potential use in the planning of therapeutic interventions and conceivably as an outcome measure.
authors.affiliation: Department of Ophthalmology, Semmelweis University, Budapest, Hungary.
authors.forename: Rita
authors.initials: R
authors.lastname: Vámos
authors.forename: Erika
authors.initials: E
authors.lastname: Tátrai
authors.forename: János
authors.initials: J
authors.lastname: Németh
authors.forename: Graham E
authors.initials: GE
authors.lastname: Holder
authors.forename: Delia Cabrera
authors.initials: DC
authors.lastname: DeBuc
authors.forename: Gábor Márk
authors.initials: GM
authors.lastname: Somfai
mesh_terms: D000293:Adolescent; D000328:Adult; D004596:Electroretinography; D005260:Female; D006801:Humans; D008266:Macula Lutea / Q000503:physiopathology*; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000473:pathology*; D017949:Retinal Cone Photoreceptor Cells / Q000473:pathology*; D012165:Retinal Ganglion Cells / Q000473:pathology*; D012174:Retinitis Pigmentosa / Q000503:physiopathology*; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology; D055815:Young Adult