title: Choroidal Line Scan Measurements in Swept-Source Optical Coherence Tomography as Surrogates for Volumetric Thickness Assessment.
abstract: OBJECTIVE
  To compare choroidal thickness of different areas on swept-source optical coherence tomography (SSOCT) line and cube scans for their interchangeable use.
  
  
  METHODS
  Validity analysis.
  
  
  METHODS
  SSOCT line and cube scans were obtained from 21 patients with various choroidal thicknesses. Subfoveal center point choroidal thickness, mean central millimeter choroidal thickness, and mean 6-mm-area choroidal thicknesses were obtained from both eyes by 2 independent graders in a reading center setting. Cross-correlations were performed using Passing and Bablok regression models. A 95% confidence interval of slope that included 1 was considered to indicate no significant difference. Average choroidal thickness of center point, Early Treatment Diabetic Retinopathy Study grid subfields, and total grid area of 6 mm on both scans and the correlation between different areas served as main outcome measures.
  
  
  RESULTS
  No significant difference between line scans/corresponding subfields of cube scans (outer nasal 0.92-1.11, inner nasal 0.88-1.06, central 0.94-1.11, inner temporal 0.95-1.12, outer temporal 0.93-1.17). No significant difference between subfoveal center point measurement/mean of choroidal thickness in the central millimeter of cube scans (0.89-1.08). Significant difference of subfoveal center point measurement or mean of central millimeter area of cube scans to entire 6-mm area of cube scans (1.01-1.53 and 1.03-1.38).
  
  
  CONCLUSIONS
  Measurements on a single SSOCT horizontal line scan can represent the entire choroid but subfoveal center point measurements are only indicative for the central millimeter area. There is a consistent overestimation of choroidal thickness when trying to estimate overall choroidal thickness from any central measurement.
authors.affiliation: Christian Doppler Laboratory for Ophthalmic Image Analysis, Medical University of Vienna, Vienna, Austria; Vienna Reading Center, Department of Ophthalmology, Medical University of Vienna, Vienna, Austria; Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.
authors.forename: Bianca S
authors.initials: BS
authors.lastname: Gerendas
authors.affiliation: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.
authors.forename: Alexander
authors.initials: A
authors.lastname: Hecht
authors.affiliation: Institute of Environmental Health, Center for Public Health, Medical University of Vienna, Vienna, Austria.
authors.forename: Michael
authors.initials: M
authors.lastname: Kundi
authors.affiliation: Christian Doppler Laboratory for Ophthalmic Image Analysis, Medical University of Vienna, Vienna, Austria; Vienna Reading Center, Department of Ophthalmology, Medical University of Vienna, Vienna, Austria; Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.
authors.forename: Sebastian M
authors.initials: SM
authors.lastname: Waldstein
authors.affiliation: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.
authors.forename: Gabor
authors.initials: G
authors.lastname: Deak
authors.affiliation: Vienna Reading Center, Department of Ophthalmology, Medical University of Vienna, Vienna, Austria; Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.
authors.forename: Christian
authors.initials: C
authors.lastname: Simader
authors.affiliation: Christian Doppler Laboratory for Ophthalmic Image Analysis, Medical University of Vienna, Vienna, Austria; Vienna Reading Center, Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.
authors.forename: Alessio
authors.initials: A
authors.lastname: Montuoro
authors.affiliation: Christian Doppler Laboratory for Ophthalmic Image Analysis, Medical University of Vienna, Vienna, Austria; Vienna Reading Center, Department of Ophthalmology, Medical University of Vienna, Vienna, Austria; Department of Ophthalmology, Medical University of Vienna, Vienna, Austria. Electronic address: ursula.schmidt-erfurth@meduniwien.ac.at.
authors.forename: Ursula
authors.initials: U
authors.lastname: Schmidt-Erfurth
authors.affiliation: Department of Ophthalmology, Medical University of Vienna, Vienna, Austria.
authors.forename: Marion
authors.initials: M
authors.lastname: Funk
mesh_terms: D000328:Adult; D002829:Choroid / Q000033:anatomy & histology*; D003941:Diagnostic Techniques, Ophthalmological; D005260:Female; D006801:Humans; D008297:Male; D009929:Organ Size; D011446:Prospective Studies; D041623:Tomography, Optical Coherence