title: VERY EARLY DISEASE MANIFESTATIONS OF MACULAR TELANGIECTASIA TYPE 2.
abstract: BACKGROUND
  To report very early morphologic and functional alterations in patients with macular telangiectasia type 2.
  
  
  METHODS
  Patients with asymmetric disease manifestations, in whom retinal alterations characteristic for macular telangiectasia type 2 were present in one but not in the apparently unaffected fellow eye, underwent multimodal imaging and functional testing (microperimetry, visual acuity, reading ability, Amsler test).
  
  
  RESULTS
  Fellow eyes not allowing the diagnosis of macular telangiectasia type 2 based on hitherto diagnostic standards consistently showed a severely reduced directional cone reflectance (Stiles-Crawford effect). Optical coherence tomography revealed an asymmetric configuration of the foveal pit with focal temporal thinning most pronounced at 1° eccentricity. Topographically related, macular pigment optical density was reduced in a small wedge-shaped temporal paracentral sector, resulting in an increased signal on fundus autofluorescence and fluorescein angiography imaging. No functional deficits were detectable in fellow eyes. Haidinger brushes were perceived in the fellow eye but not in the affected index eye with pronounced loss of macular pigment.
  
  
  CONCLUSIONS
  Specific morphologic alterations precede vascular alterations and functional deficits in macular telangiectasia type 2. The described alterations indicate a primarily degenerative process with a secondary retinal vascular phenotype, and may be helpful for early identification of patients and affected family members.
authors.affiliation: *Department of Ophthalmology, University of Bonn, Bonn, Germany; and †University Eye Clinic Maastricht, Maastricht, the Netherlands.
authors.forename: Peter
authors.initials: P
authors.lastname: Charbel Issa
authors.forename: Tjebo F C
authors.initials: TF
authors.lastname: Heeren
authors.forename: Elke H
authors.initials: EH
authors.lastname: Kupitz
authors.forename: Frank G
authors.initials: FG
authors.lastname: Holz
authors.forename: Tos T J M
authors.initials: TT
authors.lastname: Berendschot
mesh_terms: D000328:Adult; D000368:Aged; D042241:Early Diagnosis; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D009887:Ophthalmoscopy; D061848:Optical Imaging; D011446:Prospective Studies; D011932:Reading; D058456:Retinal Telangiectasis / Q000145:classification / Q000175:diagnosis* / Q000503:physiopathology; D041623:Tomography, Optical Coherence; D014786:Vision Disorders / Q000145:classification / Q000175:diagnosis* / Q000503:physiopathology; D014792:Visual Acuity / Q000502:physiology; D058609:Visual Field Tests; D014794:Visual Fields / Q000502:physiology; D055815:Young Adult