title: The external limiting membrane in early-onset Stargardt disease.
abstract: OBJECTIVE
  To describe pathologic changes of the external limiting membrane (ELM) in young patients with early-onset Stargardt (STGD1) disease.
  
  
  METHODS
  Twenty-six STGD1 patients aged younger than 20 years with confirmed disease-causing adenosine triphosphate-binding cassette, subfamily A, member 4 (ABCA4) alleles and 30 age-matched unaffected individuals were studied. Spectral-domain optical coherence tomography (SD-OCT), fundus autofluorescence (AF), and color fundus photography (CFP) images, as well as full-field electroretinograms were obtained and analyzed for one to four visits in each patient.
  
  
  RESULTS
  The ELM in all patients exhibited a distinct thickening that was not observed in unaffected individuals. In addition, accumulations of reflective deposits were noted in the outer nuclear layer in every patient. Four patients exhibited a concave protuberance or bulging of a thickened and hyperreflective ELM band within the fovea containing preserved photoreceptors. Longitudinal SD-OCT data in several patients revealed the persistence of this ELM abnormality over a period of time (1-4 years). Furthermore, the edges of the inner segment ellipsoid band appeared to recede earlier than the ELM band in active lesions.
  
  
  CONCLUSIONS
  Structural changes seen in the ELM of this cohort may reflect a gliotic response to cellular stress at the photoreceptor level in early-onset STGD1.
authors.affiliation: Department of Ophthalmology, Columbia University, New York, New York, United States.
authors.forename: Winston
authors.initials: W
authors.lastname: Lee
authors.affiliation: Department of Ophthalmology, Columbia University, New York, New York, United States Eye Clinic, Tartu University Hospital, Tartu, Estonia.
authors.forename: Kalev
authors.initials: K
authors.lastname: Nõupuu
authors.affiliation: Department of Ophthalmology, Columbia University, New York, New York, United States Eye Clinic, Tartu University Hospital, Tartu, Estonia.
authors.forename: Maris
authors.initials: M
authors.lastname: Oll
authors.affiliation: Department of Ophthalmology, Columbia University, New York, New York, United States.
authors.forename: Tobias
authors.initials: T
authors.lastname: Duncker
authors.affiliation: Department of Ophthalmology, Royal United Hospital, Bath, United Kingdom.
authors.forename: Tomas
authors.initials: T
authors.lastname: Burke
authors.affiliation: Department of Ophthalmology, Columbia University, New York, New York, United States.
authors.forename: Jana
authors.initials: J
authors.lastname: Zernant
authors.affiliation: Department of Ophthalmology, Columbia University, New York, New York, United States.
authors.forename: Srilaxmi
authors.initials: S
authors.lastname: Bearelly
authors.affiliation: Department of Ophthalmology, Columbia University, New York, New York, United States Department of Pathology & Cell Biology, Columbia University, New York, New York, United States.
authors.forename: Stephen H
authors.initials: SH
authors.lastname: Tsang
authors.affiliation: Department of Ophthalmology, Columbia University, New York, New York, United States Department of Pathology & Cell Biology, Columbia University, New York, New York, United States.
authors.forename: Janet R
authors.initials: JR
authors.lastname: Sparrow
authors.affiliation: Department of Ophthalmology, Columbia University, New York, New York, United States Department of Pathology & Cell Biology, Columbia University, New York, New York, United States.
authors.forename: Rando
authors.initials: R
authors.lastname: Allikmets
mesh_terms: D018528:ATP-Binding Cassette Transporters / Q000235:genetics* / Q000378:metabolism; D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D004247:DNA / Q000235:genetics*; D004252:DNA Mutational Analysis; D004596:Electroretinography; D063928:Ependymoglial Cells / Q000378:metabolism / Q000473:pathology*; D005260:Female; D005451:Fluorescein Angiography; D005500:Follow-Up Studies; D005654:Fundus Oculi; D006801:Humans; D008268:Macular Degeneration / Q000151:congenital* / Q000235:genetics / Q000378:metabolism / Q000473:pathology; D008297:Male; D009154:Mutation; D010641:Phenotype; D020419:Photoreceptor Cells, Vertebrate / Q000378:metabolism / Q000473:pathology*; D012189:Retrospective Studies; D000080362:Stargardt Disease; D041623:Tomography, Optical Coherence; D055815:Young Adult
chemical_list: C056475:ABCA4 protein, human; D018528:ATP-Binding Cassette Transporters; D004247:DNA
keywords: ABCA4; Müller cell; Stargardt disease; external limiting membrane; photoreceptor