title: Lipofuscin- and melanin-related fundus autofluorescence in patients with ABCA4-associated retinal dystrophies.
abstract: OBJECTIVE
  To compare melanin-related near-infrared fundus autofluorescence (NIA; excitation 787 nm, emission > 800 nm) to lipofuscin-related fundus autofluorescence (FAF; excitation 488 nm, emission > 500 nm) in patients with retinal dystrophies associated with ABCA4 gene mutations (ABCA4-RD).
  
  
  METHODS
  Observational case series.
  
  
  METHODS
  Sixteen consecutive patients with ABCA4-RD diagnosed in one institution were included. FAF and NIA imaging were performed with a confocal scanning laser ophthalmoscope (Heidelberg Retina Angiograph 2; Heidelberg Engineering, Heidelberg, Germany). The pattern and size of retinal pigment epithelial (RPE) alterations detected with FAF and NIA were evaluated.
  
  
  RESULTS
  FAF and NIA alterations were detected in all patients. In 7 of 16 patients, the alterations progressed beyond the vascular arcades, and in 9 of 16, they were confined to the macula. Spots of increased NIA (4/16) were less frequent compared with spots of increased FAF (15/16). Confluent patches of reduced NIA were frequent (12/16), and severely reduced NIA was observed in 3 cases. Areas with reduced NIA corresponded to either increased or reduced FAF. Preservation of subfoveal FAF or NIA corresponded to visual acuity > or = 0.4. Abnormalities detected with NIA were more extensive or more severe compared to FAF in 15 of 16 patients.
  
  
  CONCLUSIONS
  Patterns of FAF and NIA indicate different involvement of lipofuscin and melanin and their derivates in the pathophysiologic process of ABCA4-RD. NIA imaging provides a noninvasive in vivo visualization of RPE abnormalities that may precede FAF alterations during the degenerative process. Combined FAF and NIA imaging will provide further insight in the development of ABCA4-RD and could help to monitor future therapeutic interventions.
authors.affiliation: AugenZentrum Siegburg, Siegburg, Germany. simonekellner@retinascience.de
authors.forename: Simone
authors.initials: S
authors.lastname: Kellner
authors.forename: Ulrich
authors.initials: U
authors.lastname: Kellner
authors.forename: Bernhard H F
authors.initials: BH
authors.lastname: Weber
authors.forename: Britta
authors.initials: B
authors.lastname: Fiebig
authors.forename: Silke
authors.initials: S
authors.lastname: Weinitz
authors.forename: Klaus
authors.initials: K
authors.lastname: Ruether
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics*; D000293:Adolescent; D000328:Adult; D000368:Aged; D001284:Atrophy; D003941:Diagnostic Techniques, Ophthalmological; D005260:Female; D005453:Fluorescence; D005654:Fundus Oculi; D006801:Humans; D008062:Lipofuscin / Q000378:metabolism*; D008543:Melanins / Q000378:metabolism*; D018613:Microscopy, Confocal; D008875:Middle Aged; D009154:Mutation / Q000235:genetics; D019721:Ophthalmoscopes; D012162:Retinal Degeneration / Q000175:diagnosis* / Q000235:genetics* / Q000378:metabolism; D055213:Retinal Pigment Epithelium / Q000378:metabolism / Q000473:pathology*; D014792:Visual Acuity; D055815:Young Adult
chemical_list: C056475:ABCA4 protein, human; D018528:ATP-Binding Cassette Transporters; D008062:Lipofuscin; D008543:Melanins