Evaluation of Corneal Thickness using two different non-contact devices in adult eyes.
Autores: Blanco Torcal B; Sánchez-Pina, JMª; Lorente Hevia P; Villar Arrondo E; Carrillo Ramos V; García-Pérez J; Álvarez-Rementería Capelo L.
Trabajo presentado en el XXXV Congreso de la Sociedad Europea de Cirujanos de Catarata y Cirugía Refractiva. (ESCRS)
Ultrasound pachymetry (US) is the gold standard to measure central corneal thickness (CCT)
– Contact instrument,
– Mild patient discomfort, …
Studies comparing CCT between US and noncontact devices: 4-10
– low-coherence reflectometry
– optical coherence tomography (OCT)
– scanning-slit topography/ pachymetry
– noncontact specular microscope
– rotating Scheimpflug camera.(Pentacam, Galilei, Sirius)…
But to our knowledge, this is the first study to compare OCULUS-Pentacam® CCT measurements with the NIDEK CEM-530 Specular microscope
To compare central corneal thickness in cataratous adult eyes measured with OCULUS-Pentacam® and with the NIDEK CEM-530 Specular microscope
Prospective, observational and cross-sectional study.
CCT was measured in 84 right eyes of 84 consecutive patients .
All CCT measurements were performed by the same examiner, using a:
– Rotating Scheimpflug camera topographer (OCULUS-Pentacam®) before and after cataract surgery
– NIDEK CEM-530 (specular microscope) previous to the surgery
All measurements were made between 4 and 7 p.m. to avoid diurnal variations of CCT.
– The mean of 3 measurements was calculated for each case with the 3 devices.
|Specular Before Surgery||Pemtacam Before Surgery||Pentacam After Surgery|
|CCT (?m)||554.72 ± 29.82||546.09 ± 27.44||546.44 ± 29.33|
The Paired Student’s t-test only show a statistically significant difference (p<0.05) comparing the pachymetry before cataract surgery with the two devices
NO difference in CCT measurements in adult eyes before and after cataract extraction with Pentacam®
– can suggest that the lens opacity does not affect the pachymetry
– can also suggest that cataract surgery performed without problems does not change the corneal thickness.
There was a statiscally significative difference in CCT between OCULUS-Pentacam® and NIDEK CEM-530 in eyes before cataract surgery, but is not clinically relevant.
The OCULUS-Pentacam® Rotating Scheimpflug camera topographer and NIDEK CEM-530 specular microscope seems to be 2 interchangeable non-contact devices to measure CCT.
Autor: Barbara Blanco Torcal
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