Average 3-Dimensional Models for the Comparison of Orbscan II and Pentacam Pachymetry Maps in Normal Corneas

Repeatability of Pentacam peripheral corneal thickness measurements

“…The Pentacam's repeatability reported by Khoramnia et al [25] (CV around 1.3% at superior, inferior, nasal and temporal corneal locations) and Huang et al [3] (CV around 1.0% at 2.5 mm from the centre) is similar to the slit-scan pachymetry repeatability. Our Pentacam repeatability results, at mid-peripheral corneal locations (0.7%), indicate improved repeatability as compared to that of slitscan pachymetry [15,29] and Pentacam [3,25] and the results of this study are similar to those by Bourges et al (differences of 0.6 m nasally and 0.7 m temporally at 3.0 mm from the apex) [30].…”

Comparison of central corneal thickness estimated by an ultrasonic pachymeter and non-contact specular microscopy

“…The regression formulas given in this study could help more easily translate one measurement into another and this helps us to compare and evalua te CCT and intraocular pressure (IOP) from the former CCT and IOP history. As mentioned by Bourges et al (21) , we also believe that reproducibility and interchangeability in methods without contact to the cornea, in relation to ultrasound pachymetry, may allow for the non-contact devices to become gold standards for measuring CCT.…”

“…Some authors have claimed that tear film thickness might be added into corneal thickness when non-contact optical devices measure CCT; however, tear film is compressed by the pachymeter probe when using UP (17)(18)(19) . Reproducibility of the applications is also important, and some studies have shown that the reproducibility of the optical devices is high (20,21) . However, with UP, it is difficult to maintain the same points and the perpendicularity of the ultrasound probe in sequential measurements.…”

“…However, this does not mean that these measurement methods are interchangeable. Bourges et al reported that non-contact methods are reproducible and interchangeable with each other; however, interchangeability with UP has been found to be limited (21) . In conclusion, in this study we obtained thinner CCT measurements with NCSM compared to UP, widely regarded to be the gold standard.…”

Cataract Surgery in Keratoconus with Irregular Astigmatism

“…They provide "optical" keratometries closer to the manifest refraction than specular values. This objective method is more reproducible to prevent IOL power miscalculation, although it should be stressed that elevation topographs have their own limits in reproducibility and their data are not interchangeable for analysis (Bourges et al, 2009, Quisling et al, 2006. Within a single acquisition, the elevation topograph (Pentacam, Oculus) provides both the anterior refractive power and the true net power of the cornea, which vary significantly for this keratoconic patient.…”