MEASUREMENT TO COMPARE THE CORNEAL CENTRAL THICKNESS WITH PENTACAM, VISANTE AND ULTRASONIC PACHYMETRY AT OFTALMOSALUD EYE INSTITUTE Authors: Miranda Mauricio, MD; Gutarra Villavicencio Rosario del Pilar, MD; Izquierdo Jr. Luis, MD; Cañote Flores Renzo, MD; Bernilla F. César, MD. Institution: Instituto de Ojos Oftalmosalud Address: Av. Javier Prado Este 1142 San Isidro. *The authors have no financial interest in the materials being presented

To compare the values of measurement of corneal thickness obtained by Pentacam, Visante and Ultrasonic Pachymetry. PURPOSE

Prospective, comparative simple study of corneal pachymetry, in a sample of 54 eyes of 54 patients taken care of at OFTALMOSALUD Eye Institute during the period, between November and December of the year The values of corneal thickness were obtained by 3 devices (Visante®, Pentacam® and ultrasonic Pachymeter Accutome®). MATERIALS AND METHODS

Inclusion criteria considered: - Age greater than 18 years old - Patient that accepts to participate voluntarily in the study. - Do not have corneal pathology with the exception of keratocono, any ocular surgery or use of contact lenses. -Do not have family history of ocular disease or systemic disease with ocular manifestations Exclusion criteria considered: - Age lower than 18 years old. - Pregnant women - Previous refracting Surgery - Corneal Pathology except keratocono, ocular surgery or use of contact lenses - Family History of ocular disease or systemic disease with ocular manifestations. MATERIALS AND METHODS

All the measurements were made in the afternoon between 4 and 6 p.m., with the purpose of avoiding the normal diurnal variations of the corneal thickness. These studies gave a level of confidence of 95%, during this study 54 subjects showed a probability to have 80% to detect 45µm, of difference in averages. MATERIALS AND METHODS

RESULTS The age average of patients was of 28, DS The patient with smaller age was 18 years old and the one of greater age was 58 years old. The 85,2% (46 patients) were of female sex and 14.8% (8 patients) male.

RESULTS We obtained a medium correlation between the VISANTE and U.S. of 0,647 (64,7%) and between U.S. and PENTACAM of 0,690 (69%).

RESULTS

There were variations in the readings of corneal central thickness between the 3 devices. The measures of central corneal thickness in normal eyes with Pentacam revealed an excellent correlation with the results obtained with ultrasonic pachymetry. The measures of corneal thickness with the Visante System turned out to be smaller than with the Pentacam and ultrasonic pachymetry. The results suggest that the Pentacam and the U.S. is equally precise, giving similar readings. CONCLUSIONS

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