Evaluation of Corneal Thickness using two different non-contact devices in adult eyes.

ESCRS Evaluation of Corneal Thickness using two different non-contact devices in adult eyes

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)

INTRODUCTION:

Ultrasound pachymetry (US) is the gold standard to measure central corneal thickness (CCT)
limitations: 1-3

– Reproducibility,
– 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

PURPOSE

To compare central corneal thickness in cataratous adult eyes measured with OCULUS-Pentacam® and with the NIDEK CEM-530 Specular microscope

METHODS

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.

RESULTS

 Specular Before SurgeryPemtacam Before SurgeryPentacam After Surgery
CCT (?m)554.72 ± 29.82546.09 ± 27.44  546.44 ± 29.33

p<0.05

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

CONCLUSION

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
Óptico-Optometrista


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Última modificación de la web: 4 December 2017