On the right, the elevation of the front surface relative to the reference surface is on top, and the posterior surface relative to its reference surface is at the bottom. Clinical applications of kerwtoconus confocal microscopy. The axial curvature map, also known as keratovonus sagittal map, depicts the curvature of the anterior corneal surface in dioptric values for each point. Keratoconus Furthermore, new algorithms and combined indices have been introduced, aiming at earlier and more precise KC detection [ 67 ]. As corneal refractive surgery evolves, professional expectations increase and require continuous refinements of preoperative screening and interpretation [ 1 ]. In kerafoconus situation, anf is a powerful aid.
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Production and hosting by Elsevier B. This article has been cited by other articles in PMC. Abstract Purpose To determine pachymetric, aberrometric, and topometric indices in patients with definite and subclinical keratoconus and the validity of these indices in the diagnosis of keratoconus. Methods We evaluated keratoconic and 97 healthy eyes in this study. Pentacam HR examination was performed for all participants, and the data of all pachymetric, aberrometric, and topometric indices was extracted for the study population.
The sensitivity and specificity of the above-mentioned models were However, the aforementioned indices do not negate the importance of widely recognized and acceptable indices like keratometry and central corneal thickness. Introduction Keratoconus often starts to develop at the age of puberty as a corneal ectatic disorder. A diagnosis of keratoconus is most commonly made through slit lamp examination, corneal topography, and measurement of visual acuity and refraction.
Since slit lamp examination is unable to show the signs of keratoconus in the early stages and visual acuity may not be affected, corneal topography is the only reliable criterion. Keratoconus diagnostic indices and some pachymetric indices are among the indices measured by Pentacam which were evaluated in this study in order to facilitate the diagnosis of this condition. In addition to the changes of these indices in patients with definite keratoconus, we investigated their use in detecting the cases of subclinical keratoconus and presented some cut-off points, which are clinically important.
Methods In this cross-sectional study, we evaluated keratoconus patients who were visited in the keratoconus clinic of Noor Eye Hospital in the second half of and received Pentacam HR examination. Keratoconus diagnosis had been confirmed by thorough clinical examination and corneal topography.
The control group was selected from among the candidates of refractive surgery who did not have a history of ocular surgery and their corneal topography with Pentacam was normal. Due to the high number of the people in the control group, one month in the six-month period of the study was randomly selected, and all eligible individuals in that month were included in the control group.
The data of the pachymetric, topometric, and aberrometric indices, which are shown in Table 1 , was extracted from the Pentacam software.
The average of the evaluated indices in the control, subclinical, and definite groups was compared using ANCOVA, and the effects of age and sex were controlled. A stepwise logistic regression model was used to control the effect of age and sex and to determine the effective indices in detecting the cases of subclinical and definite keratoconus. The diagnostic specificity and sensitivity of these indices, in comparison with clinical examination and McMahon criteria, were evaluated and compared with Receiver Operating Curve ROC , and cut-off points were presented.
KERATOCONUS AND PENTACAM PDF
Pentacam top indices for diagnosing subclinical and definite keratoconus