title: Tracking progression with spectral-domain optical coherence tomography in geographic atrophy caused by age-related macular degeneration.
abstract: OBJECTIVE
  To investigate, with the use of spectral-domain optical coherence tomography (SD-OCT), microstructural alterations over time in eyes with progressive geographic atrophy (GA) due to age-related macular degeneration.
  
  
  METHODS
  Forty-six eyes of 26 patients (median age, 77.9 years [interquartile range (IQR), 71.8-81.0]) with GA without evidence of active or previous neovascular disease at baseline were examined by simultaneous confocal scanning laser ophthalmoscopy (cSLO) and SD-OCT. Serial examinations with alignment of follow-up to baseline scans were performed over a median period of 12.2 months (IQR, 10.2-15.3). Longitudinal SD-OCT variations were evaluated, including quantification of retinal thickness (RT) change and lateral spread of GA (LSGA) at a temporal, nasal, inferior, and superior GA border-section in each eye.
  
  
  RESULTS
  GA-enlargement was characterized by progressive loss of the outer hyperreflective SD-OCT bands and by thinning of the outer nuclear layer with subsequent approach of the outer plexiform layer toward Bruch's membrane. In the perilesional zone, various dynamic changes were recorded, including migration of hyperreflective material and changes in drusen height. At the borders, there was a median RT change of -14.09 microm/y (IQR -26.21 to -7.48 microm/y). The median LSGA was 106.90 microm/y (IQR, 55.44-161.70 microm/y). Both parameters showed only moderate intraocular agreement (RT change: intraclass correlation coefficient [ICC], 0.54; 95% CI, 0.39-0.67; LSGA: ICC, 0.49; 95% CI, 0.34-0.64) and no statistical significant difference for one location (RT change, P = 0.125; LSGA, P = 0.516; likelihood ratio test).
  
  
  CONCLUSIONS
  Combined cSLO and SD-OCT imaging provides unprecedented insight into dynamic microstructural changes of GA enlargement that may help to better understand the pathogenesis of the disease. Quantitative progression data indicate local factors may exist that drive progression in junctional areas (ClinicalTrials.gov number, NCT00393692).
authors.affiliation: Department of Ophthalmology, University of Bonn, Bonn, Germany.
authors.forename: Monika
authors.initials: M
authors.lastname: Fleckenstein
authors.forename: Steffen
authors.initials: S
authors.lastname: Schmitz-Valckenberg
authors.forename: Christine
authors.initials: C
authors.lastname: Adrion
authors.forename: Irene
authors.initials: I
authors.lastname: Krämer
authors.forename: Nicole
authors.initials: N
authors.lastname: Eter
authors.forename: Hans Martin
authors.initials: HM
authors.lastname: Helb
authors.forename: Christian K
authors.initials: CK
authors.lastname: Brinkmann
authors.forename: Peter
authors.initials: P
authors.lastname: Charbel Issa
authors.forename: Ulrich
authors.initials: U
authors.lastname: Mansmann
authors.forename: Frank G
authors.initials: FG
authors.lastname: Holz
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D018450:Disease Progression; D005260:Female; D005500:Follow-Up Studies; D057092:Geographic Atrophy / Q000175:diagnosis* / Q000209:etiology / Q000503:physiopathology; D006801:Humans; D008268:Macular Degeneration / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D009887:Ophthalmoscopy; D011446:Prospective Studies; D012160:Retina / Q000473:pathology*; D055213:Retinal Pigment Epithelium / Q000473:pathology*; D041623:Tomography, Optical Coherence