title: Comparative evaluation of dual Scheimpflug imaging parameters in keratoconus, early keratoconus, and normal eyes.
abstract: OBJECTIVE
  To determine the efficacy of various parameters measured by dual Scheimpflug imaging technology in differentiating eyes with keratoconus or early keratoconus from normal eyes.
  
  
  METHODS
  Cornea Service, Wills Eye Institute, Philadelphia, Pennsylvania, USA.
  
  
  METHODS
  Comparative case series.
  
  
  METHODS
  A retrospective evaluation was performed of the parameters provided by the Galilei dual Scheimpflug analyzer in keratoconus, early keratoconus, and normal eyes. Logistic regression and receiver operating characteristic curve analysis were used to compare the mean values and to calculate the sensitivity and specificity of these parameters.
  
  
  RESULTS
  Many parameters were statistically significantly different between keratoconus and normal eyes compared with early keratoconus eyes (P<.05). Total cornea power-steep and posterior curvature-steep keratometry had the highest area under the curve (AUC) score (0.99) for differentiating keratoconus eyes from normal eyes. All anterior curvature parameters were statistically significant in differentiating keratoconus eyes from normal eyes, whereas only the anterior curvature-steep was statistically significant in differentiating early keratoconus eyes from normal eyes. The central pachymetry and thinnest pachymetry were statistically significant in differentiating keratoconus and early keratoconus eyes from normal eyes. Third-order root mean square (RMS) and total RMS had the highest AUC scores (0.83 and 0.82, respectively) for differentiating early keratoconus eyes from normal eyes.
  
  
  CONCLUSIONS
  Total corneal power, anterior curvature, posterior curvature, pachymetry, and corneal aberration data generated from the dual Scheimpflug analyzer showed promising results in differentiating keratoconus and early keratoconus eyes from normal eyes.
  
  
  BACKGROUND
  No author has a financial or proprietary interest in any material or method mentioned.
authors.affiliation: From the Cornea Service (Reddy, Rapuano, Cater, Suri, Nagra, Hammersmith), Wills Eye Institute, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, USA; Cornea, Anterior Segment and Refractive Surgery Services (Reddy), LV Prasad Eyes Institute, Kallam Anji Reddy Campus, Hyderabad, India.
authors.forename: Jagadesh C
authors.initials: JC
authors.lastname: Reddy
authors.affiliation: From the Cornea Service (Reddy, Rapuano, Cater, Suri, Nagra, Hammersmith), Wills Eye Institute, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, USA; Cornea, Anterior Segment and Refractive Surgery Services (Reddy), LV Prasad Eyes Institute, Kallam Anji Reddy Campus, Hyderabad, India. Electronic address: cjrapuano@willseye.org.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Rapuano
authors.affiliation: From the Cornea Service (Reddy, Rapuano, Cater, Suri, Nagra, Hammersmith), Wills Eye Institute, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, USA; Cornea, Anterior Segment and Refractive Surgery Services (Reddy), LV Prasad Eyes Institute, Kallam Anji Reddy Campus, Hyderabad, India.
authors.forename: Jacqueline R
authors.initials: JR
authors.lastname: Cater
authors.affiliation: From the Cornea Service (Reddy, Rapuano, Cater, Suri, Nagra, Hammersmith), Wills Eye Institute, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, USA; Cornea, Anterior Segment and Refractive Surgery Services (Reddy), LV Prasad Eyes Institute, Kallam Anji Reddy Campus, Hyderabad, India.
authors.forename: Kunal
authors.initials: K
authors.lastname: Suri
authors.affiliation: From the Cornea Service (Reddy, Rapuano, Cater, Suri, Nagra, Hammersmith), Wills Eye Institute, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, USA; Cornea, Anterior Segment and Refractive Surgery Services (Reddy), LV Prasad Eyes Institute, Kallam Anji Reddy Campus, Hyderabad, India.
authors.forename: Parveen K
authors.initials: PK
authors.lastname: Nagra
authors.affiliation: From the Cornea Service (Reddy, Rapuano, Cater, Suri, Nagra, Hammersmith), Wills Eye Institute, Jefferson Medical College of Thomas Jefferson University, Philadelphia, Pennsylvania, USA; Cornea, Anterior Segment and Refractive Surgery Services (Reddy), LV Prasad Eyes Institute, Kallam Anji Reddy Campus, Hyderabad, India.
authors.forename: Kristin M
authors.initials: KM
authors.lastname: Hammersmith
mesh_terms: D057128:Aberrometry; D000293:Adolescent; D000328:Adult; D002648:Child; D003315:Cornea / Q000473:pathology*; D063171:Corneal Pachymetry; D057108:Corneal Wavefront Aberration / Q000503:physiopathology; D003952:Diagnostic Imaging / Q000379:methods*; D003941:Diagnostic Techniques, Ophthalmological / Q000295:instrumentation*; D042241:Early Diagnosis; D005260:Female; D064368:Healthy Volunteers; D006801:Humans; D007640:Keratoconus / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D012372:ROC Curve; D012189:Retrospective Studies; D055815:Young Adult