PMID- 22274296
OWN - NLM
STAT- MEDLINE
DCOM- 20120529
LR  - 20211021
IS  - 1433-0423 (Electronic)
IS  - 0941-293X (Linking)
VI  - 109
IP  - 1
DP  - 2012 Jan
TI  - [Suitability of various topographic corneal parameters for diagnosis of early 
      keratoconus].
PG  - 37-44
LID - 10.1007/s00347-011-2446-2 [doi]
AB  - BACKGROUND: For the detection of early stages of keratoconus (KC) several metrics 
      have been developed in recent years. The aim of the study was to assess the 
      suitability of keratometric indices to discriminate between eyes with early and 
      subclinical KC from normal eyes. METHODS: From 33 eyes with early KC (group 1), 
      16 eyes with subclinical KC (group 2) und 121 normal eyes (group 3) the following 
      metrics were computed from axial keratometric data: central keratometry (cK), 
      astigmatism (AST), paracentral inferior-superior keratometric difference (PISD), 
      skew of the steepest axes index (SRAX), the KISA% index, a discriminant function 
      from the KISA% parameters AST, cK, PISD and SRAX (DKISA), corneal C(3) (-1) and a 
      discriminant function from corneal Zernike coefficients (1(st)-7(th) order, pupil 
      diameter 6 mm). The discriminative ability of these metrics between KC and normal 
      eyes was assessed using receiver operating characteristic (ROC) curves and 
      measuring the area under the curve (A (z)ROC). RESULTS: Applying the published 
      criteria, the Rabinowitz-McDonnell test (cK and PISD) and KISA% lacked 
      sensitivity. Adjustment of critical values using ROC curve analysis improved the 
      discriminative ability. The PISD (A (z)ROC 1 versus 3: 1, 2 versus 3: 0.947) and 
      C(3) (-1) (A (z)ROC 1 and 0.98, respectively) metrics were the two single 
      parameters with the highest discriminative ability. By weighting KISA parameters 
      and Zernike coefficients with discriminant analyses, 100% of group 1 eyes (DKISA) 
      and 96.7% of group 2 eyes (DA) were correctly classified. CONCLUSION: After 
      lowering the critical values the keratometric indices yielded a high 
      discriminative ability for the detection of early KC stages. However, the 
      excellent classification rates for wavefront-based metrics were not achieved.
FAU - Buhren, J
AU  - Buhren J
AD  - Klinik fur Augenheilkunde, Johann Wolfgang Goethe-Universitat, Theodor-Stern-Kai 
      7, 60590, Frankfurt am Main, Deutschland. buehren@em.uni-frankfurt.de
FAU - Kook, D
AU  - Kook D
FAU - Kohnen, T
AU  - Kohnen T
LA  - ger
PT  - Comparative Study
PT  - English Abstract
PT  - Journal Article
TT  - Eignung unterschiedlicher korneal topographischer Masszahlen zur Diagnose des 
      fruhen Keratokonus.
PL  - Germany
TA  - Ophthalmologe
JT  - Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft
JID - 9206148
SB  - IM
MH  - Adolescent
MH  - Adult
MH  - *Algorithms
MH  - Corneal Topography/*methods
MH  - Diagnosis, Computer-Assisted/*methods
MH  - Early Diagnosis
MH  - Female
MH  - Humans
MH  - Keratoconus/*diagnosis
MH  - Middle Aged
MH  - Reproducibility of Results
MH  - Sensitivity and Specificity
MH  - Young Adult
EDAT- 2012/01/26 06:00
MHDA- 2012/05/30 06:00
CRDT- 2012/01/26 06:00
PHST- 2012/01/26 06:00 [entrez]
PHST- 2012/01/26 06:00 [pubmed]
PHST- 2012/05/30 06:00 [medline]
AID - 10.1007/s00347-011-2446-2 [doi]
PST - ppublish
SO  - Ophthalmologe. 2012 Jan;109(1):37-44. doi: 10.1007/s00347-011-2446-2.