Corneal thickness measurements: Scanning-slit corneal topography and noncontact specular microscopy versus ultrasonic pachymetry

Abstract

Corneal thickness readings were comparable between scanning-slit topography and pachymetry; noncontact specular microscopy gave significantly smaller values. The measurements of the 3 methods showed significant linear correlations with one another. All methods provided acceptable repeatability of measurements.

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

“…Al-Ageel and Al Muammar reported that CCT was significantly thinner when measured with specular microscope (SM) (511.9 ± 38.6) (SP-2000P, Topcon Corporation, Tokyo, Japan) than when measured with UP (533.3 ± 37.9) (SP-3000, Tomey Corporation, Nagoya, Japan) and that the two instruments were in good correlation while measuring 94 normal eyes of 47 patients, with a mean age of 33 years (12) . In a multicenter study in Japan, both Orbscan and UP measurements were significantly higher than NSCM (SP-2000P, Topcon Corporation, Tokyo, Japan) measurements and ultrasonic pachymetry correlated with NCSM (13) . In contrast, Khaja et al reported lower values when comparing measurements made by UP vs. SM.…”

“…Most of these studies reported that UP measurements were thicker than NCSM mea surements (10)(11)(12)(13) . Modis et al examined 73 eyes from 44 patients (mean age 66 years) with normal corneas comparing three different devices: NCSM (Topcon SP-2000P; Topcon Corporation, Tokyo, Japan), UP (AL-1000; Tomey, Erlangen, Germany), and contact specular microscope (CSM) (EM-1000; Tomey, Tokyo, Japan).…”

The comparative study of two recently developed A‐scan devices: determination of central corneal thickness, anterior chamber depth and axial length

“…This information could be useful to the clinician who wants to compare CCT on a referral, where each physician has used different devices. Mo´dis et al (2001b) 570 ± 42 Bovelle et al (1999) 559.9 ± 5.5 Chakrabarti et al (2001) 538 ± 36.7 Javaloy et al (2004) 553.7 ± 25.7 McLaren et al (2004) 555 ± 28 554 ± 28 Rainer et al (2002) 541 539.2 545.1 Suzuki et al (2003) 548.1 ± 33 Tam & Rootman (2003) 550 ± 4.14 Rainer et al (2004) 544.5 ± 35.2 542.2 ± 34.3 Viestenz et al (2004) 542 ± 35 Table 3. Anterior chamber depth (ACD) using contact ultrasound biometry, as reported in the literature.…”

Pentacam ile Ölçülen Santral Kornea Kalınlıklarının Karşılaştırılması

“…Ultrasonik yöntemler aras›nda ultrasonik pakimetre ve ultrasonik biyomikroskop (UBM), optik yöntemler aras›nda ise speküler mikroskopi, optik koherans tomografi, taray›c› slit kornea topografisi, konfokal mikroskopi ve Pentacam Scheimpflug sistem say›labilir. 1,[7][8][9][10][11][12][13][14][15][16][17] Ultrasonik pakimetri, ucuz ve kolay uygulanabilir bir teknoloji olmas›, ölçümlerinin yüksek tekrarlanabilirlikte ve güvenilirlikte olmas› nedeniyle klinik uygulamalarda yayg›n olarak kullan›lmaktad›r. 13,[18][19][20] Korneaya temas etmesi en önemli dezavantaj›d›r ve epitel defektlerine ve enfeksiyonlara yol açabilmektedir.…”