Noncontact corneal pachymetry with slit lamp-adapted optical coherence tomography

Wirbelauer, Christopher; Scholz, Christian; Hoerauf, Hans; Thoai Pham, Duy; Laqua, Horst; Birngruber, Reginald

« Previous Next »American Journal of Ophthalmology
Volume 133, Issue 4 , Pages 444-450, April 2002

Noncontact corneal pachymetry with slit lamp-adapted optical coherence tomography

Christopher Wirbelauer, MD
- Reprint requests to Christopher Wirbelauer, MD, Klinik für Augenheilkunde, Vivantes-Klinikum Neukölln, Rudower Strasse 48, D-12351 Berlin, Germany; fax: (49) 30-60043546
- Klinik für Augenheilkunde, Vivantes-Klinikum Neukölln, Berlin, Germany (C.W., D.T.P.)
- Augenklinik der Medizinischen Universität zu, Lübeck, Lübeck, Germany (C.W., H.H., H.L.)
- The authors have no commercial, proprietary, or financial interest in any research or devices described in the presented study.
Christian Scholz, MSc
- Medizinisches Laserzentrum Lübeck, Lübeck, Germany (C.S., R.B.)
- The authors have no commercial, proprietary, or financial interest in any research or devices described in the presented study.
Hans Hoerauf, MD
- Augenklinik der Medizinischen Universität zu, Lübeck, Lübeck, Germany (C.W., H.H., H.L.)
- The authors have no commercial, proprietary, or financial interest in any research or devices described in the presented study.
Duy Thoai Pham, MD
- Klinik für Augenheilkunde, Vivantes-Klinikum Neukölln, Berlin, Germany (C.W., D.T.P.)
- The authors have no commercial, proprietary, or financial interest in any research or devices described in the presented study.
Horst Laqua, MD
- Augenklinik der Medizinischen Universität zu, Lübeck, Lübeck, Germany (C.W., H.H., H.L.)
- The authors have no commercial, proprietary, or financial interest in any research or devices described in the presented study.
Reginald Birngruber, PhD
- Medizinisches Laserzentrum Lübeck, Lübeck, Germany (C.S., R.B.)
- The authors have no commercial, proprietary, or financial interest in any research or devices described in the presented study.

Accepted 10 December 2001.

Abstract

PURPOSE: The purpose of this study was to determine the accuracy, the reproducibility, and the limits of agreement of noncontact central corneal thickness measurement with slit lamp-adapted optical coherence tomography (OCT).

DESIGN: Nonrandomized comparative clinical trial.

METHODS: In a prospective comparative observational study, a total of 108 consecutive patients (108 eyes) with normal corneas (92 eyes) and different corneal alterations (16 eyes) participated. Six sequential measurements of the central corneal thickness with slit lamp-adapted OCT and with ultrasound (US) pachymetry at 1640 ms⁻¹ were performed. The main outcome measures were accuracy, reproducibility assessed with precision and coefficient of variation (CV), and limits of agreement of central corneal thickness measurement.

RESULTS: The mean central corneal thickness values were 541 ± 43 μm (OCT) and 549 ± 44 μm (US) with a mean precision of ± 5.8 μm (CV 1.08%) and of ± 4.0 μm (CV 0.73%), respectively. The method comparison revealed equivalence (± 2SD) in the 5% range with a mean difference between both methods of 7.9 μm (1.45%). The relative error was 8.7 μm (1.6%), which corresponded to limits of agreement (± 2SD) ranging from −9.5 μm to 25.3 μm.

CONCLUSIONS: Central corneal pachymetry with slit lamp-adapted OCT revealed, for clinical purposes, an excellent accuracy and reproducibility with a high degree of agreement compared with US pachymetry. Thus, the presented OCT system seems to be a promising diagnostic modality to objectively measure corneal thickness in a convenient noncontact mode.