Abstract
Purpose :
Keratometry values and astigmatism have applications in the screening prior to refractive surgery, in the diagnosis of corneal diseases and in the calculation of intraocular lenses. We performed a retrospective observational study to describe keratometry and astigmatic values from a rotating Scheimpflug camera in Mexican patients with ametropia, cataract and corneal ectasia.
Methods :
Retrospective analysis of medical records of patients undergoing Petacam topography for diagnosis of ametropia, cataract and corneal ectasia from October 2021 to September 2023. A descriptive analysis of flatter keratometry, curved keratometry, corneal astigmatism and axis, as well as apex pachymetry and thinner pachymetry was performed. The patients were divided into three age groups: 20 to 39 years, 40 to 59 years and 60 to 80 years.
Results :
A total of 1935 patients were included. Patients with diagnosed ametropia and cataract were grouped as non-pathological and patients with corneal ectasia were grouped as pathological. Patients in the non-pathological and pathological group aged 20-39 years reported a mean flat keratometry of 42.1±1.78 and 44.60±3.65, a mean curved keratometry of 44.64±2.17 and 48.68±4.61, an astigmatism of 4.07±2.14 and 2.46±1.65 diopters, an apex pachymetry of 539.43±32 and 495.85±49 microns and a thinner pachymetry of 534.2±32 and 487.21±21microns respectively.
Patients in the non-pathological and pathological group aged 40-59 years reported a mean flat keratometry of 42.94±1.90 and 45.93±4.46, a mean curved keratometry of 44.51±2.10 aand 49.31±5.1, an astigmatism of 1.56±1.26 and 3.37±2.43 diopters, a pachymetry at the apex of 535.81±34 and 481.88±56 microns and a thinner pachymetry of 529.51±36 and 470±58 microns respectively.
Patients in the non-pathological and pathological group aged 60 to 80 years reported a mean flat keratometry of 43.32±1.90 and 44.38±1.95, a mean curved keratometry of 44.38±1.95 and 46.07±5.69, an astigmatism of 1.05±1.01and 2.66±3.65 diopters, a pachymetry at the apex of 534.91±31 and 519.25±46 microns, and a thinner pachymetry of 528.71±31.07 and 508.875±53 microns respectively.
Conclusions :
There was a tendency for the pathological group to have higher flat and curved keratometry and thinner pachymetry as previously observed in studies from other populations.
This abstract was presented at the 2024 ARVO Annual Meeting, held in Seattle, WA, May 5-9, 2024.