Corneal confocal microscopy is a rapid reproducible ophthalmic technique for quantifying corneal nerve abnormalities

Alise Kalteniece, Maryam Ferdousi, Safwaan Adam, Jonathan Schofield, Shazli Azmi, Ioannis Petropoulos, Handrean Soran, Rayaz Malik

Research output: Contribution to journalArticle

18 Citations (Scopus)

Abstract

Purpose To assess the effect of applying a protocol for image selection and the number of images required for adequate quantification of corneal nerve pathology using in vivo corneal confocal microscopy (IVCCM). Methods IVCCM was performed in 35 participants by a single examiner. For each participant, 4 observers used a standardized protocol to select 6 central corneal nerve images to assess the inter-observer variability. Furthermore, images were selected by a single observer on two occasions to assess intra-observer variability and the effect of sample size was assessed by comparing 6 with 12 images. Corneal nerve fiber density (CNFD), branch density (CNBD) and length (CNFL) were quantified using fully automated software. The data were compared using the intra class correlation coefficient (ICC) and Bland-Altman agreement plots for all experiments. Results The ICC values for CNFD, CNBD and CNFL were 0.93 (P<0.0001), 0.96 (P<0.0001) and 0.95 (P<0.0001) for inter-observer variability and 0.95 (P<0.0001), 0.97 (P<0.001) and 0.97 (P<0.0001) for intra-observer variability. For sample size variability, ICC values were 0.94 (P<0.0001), 0.95 (P<0.0001), and 0.96 (P<0.0001) for CNFD, CNBD and CNFL. Bland-Altman plots showed excellent agreement for all parameters. Conclusions This study shows that implementing a standardized protocol to select IVCCM images results in high intra and inter-observer reproducibility for all corneal nerve parameters and 6 images are adequate for analysis. IVCCM could therefore be deployed in large multicenter clinical trials with confidence.

Original languageEnglish
Article numbere0183040
JournalPLoS One
Volume12
Issue number8
DOIs
Publication statusPublished - 1 Aug 2017

Fingerprint

Observer Variation
Confocal microscopy
Confocal Microscopy
nerve tissue
eyes
Nerve Fibers
nerve fibers
Sample Size
Fibers
Pathology
methodology
Multicenter Studies
Software
Clinical Trials
reproducibility
confocal microscopy
clinical trials
sampling
Experiments

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Agricultural and Biological Sciences(all)

Cite this

Corneal confocal microscopy is a rapid reproducible ophthalmic technique for quantifying corneal nerve abnormalities. / Kalteniece, Alise; Ferdousi, Maryam; Adam, Safwaan; Schofield, Jonathan; Azmi, Shazli; Petropoulos, Ioannis; Soran, Handrean; Malik, Rayaz.

In: PLoS One, Vol. 12, No. 8, e0183040, 01.08.2017.

Research output: Contribution to journalArticle

Kalteniece, A, Ferdousi, M, Adam, S, Schofield, J, Azmi, S, Petropoulos, I, Soran, H & Malik, R 2017, 'Corneal confocal microscopy is a rapid reproducible ophthalmic technique for quantifying corneal nerve abnormalities', PLoS One, vol. 12, no. 8, e0183040. https://doi.org/10.1371/journal.pone.0183040
Kalteniece, Alise ; Ferdousi, Maryam ; Adam, Safwaan ; Schofield, Jonathan ; Azmi, Shazli ; Petropoulos, Ioannis ; Soran, Handrean ; Malik, Rayaz. / Corneal confocal microscopy is a rapid reproducible ophthalmic technique for quantifying corneal nerve abnormalities. In: PLoS One. 2017 ; Vol. 12, No. 8.
@article{be85dc8332944977b55a072443c9e460,
title = "Corneal confocal microscopy is a rapid reproducible ophthalmic technique for quantifying corneal nerve abnormalities",
abstract = "Purpose To assess the effect of applying a protocol for image selection and the number of images required for adequate quantification of corneal nerve pathology using in vivo corneal confocal microscopy (IVCCM). Methods IVCCM was performed in 35 participants by a single examiner. For each participant, 4 observers used a standardized protocol to select 6 central corneal nerve images to assess the inter-observer variability. Furthermore, images were selected by a single observer on two occasions to assess intra-observer variability and the effect of sample size was assessed by comparing 6 with 12 images. Corneal nerve fiber density (CNFD), branch density (CNBD) and length (CNFL) were quantified using fully automated software. The data were compared using the intra class correlation coefficient (ICC) and Bland-Altman agreement plots for all experiments. Results The ICC values for CNFD, CNBD and CNFL were 0.93 (P<0.0001), 0.96 (P<0.0001) and 0.95 (P<0.0001) for inter-observer variability and 0.95 (P<0.0001), 0.97 (P<0.001) and 0.97 (P<0.0001) for intra-observer variability. For sample size variability, ICC values were 0.94 (P<0.0001), 0.95 (P<0.0001), and 0.96 (P<0.0001) for CNFD, CNBD and CNFL. Bland-Altman plots showed excellent agreement for all parameters. Conclusions This study shows that implementing a standardized protocol to select IVCCM images results in high intra and inter-observer reproducibility for all corneal nerve parameters and 6 images are adequate for analysis. IVCCM could therefore be deployed in large multicenter clinical trials with confidence.",
author = "Alise Kalteniece and Maryam Ferdousi and Safwaan Adam and Jonathan Schofield and Shazli Azmi and Ioannis Petropoulos and Handrean Soran and Rayaz Malik",
year = "2017",
month = "8",
day = "1",
doi = "10.1371/journal.pone.0183040",
language = "English",
volume = "12",
journal = "PLoS One",
issn = "1932-6203",
publisher = "Public Library of Science",
number = "8",

}

TY - JOUR

T1 - Corneal confocal microscopy is a rapid reproducible ophthalmic technique for quantifying corneal nerve abnormalities

AU - Kalteniece, Alise

AU - Ferdousi, Maryam

AU - Adam, Safwaan

AU - Schofield, Jonathan

AU - Azmi, Shazli

AU - Petropoulos, Ioannis

AU - Soran, Handrean

AU - Malik, Rayaz

PY - 2017/8/1

Y1 - 2017/8/1

N2 - Purpose To assess the effect of applying a protocol for image selection and the number of images required for adequate quantification of corneal nerve pathology using in vivo corneal confocal microscopy (IVCCM). Methods IVCCM was performed in 35 participants by a single examiner. For each participant, 4 observers used a standardized protocol to select 6 central corneal nerve images to assess the inter-observer variability. Furthermore, images were selected by a single observer on two occasions to assess intra-observer variability and the effect of sample size was assessed by comparing 6 with 12 images. Corneal nerve fiber density (CNFD), branch density (CNBD) and length (CNFL) were quantified using fully automated software. The data were compared using the intra class correlation coefficient (ICC) and Bland-Altman agreement plots for all experiments. Results The ICC values for CNFD, CNBD and CNFL were 0.93 (P<0.0001), 0.96 (P<0.0001) and 0.95 (P<0.0001) for inter-observer variability and 0.95 (P<0.0001), 0.97 (P<0.001) and 0.97 (P<0.0001) for intra-observer variability. For sample size variability, ICC values were 0.94 (P<0.0001), 0.95 (P<0.0001), and 0.96 (P<0.0001) for CNFD, CNBD and CNFL. Bland-Altman plots showed excellent agreement for all parameters. Conclusions This study shows that implementing a standardized protocol to select IVCCM images results in high intra and inter-observer reproducibility for all corneal nerve parameters and 6 images are adequate for analysis. IVCCM could therefore be deployed in large multicenter clinical trials with confidence.

AB - Purpose To assess the effect of applying a protocol for image selection and the number of images required for adequate quantification of corneal nerve pathology using in vivo corneal confocal microscopy (IVCCM). Methods IVCCM was performed in 35 participants by a single examiner. For each participant, 4 observers used a standardized protocol to select 6 central corneal nerve images to assess the inter-observer variability. Furthermore, images were selected by a single observer on two occasions to assess intra-observer variability and the effect of sample size was assessed by comparing 6 with 12 images. Corneal nerve fiber density (CNFD), branch density (CNBD) and length (CNFL) were quantified using fully automated software. The data were compared using the intra class correlation coefficient (ICC) and Bland-Altman agreement plots for all experiments. Results The ICC values for CNFD, CNBD and CNFL were 0.93 (P<0.0001), 0.96 (P<0.0001) and 0.95 (P<0.0001) for inter-observer variability and 0.95 (P<0.0001), 0.97 (P<0.001) and 0.97 (P<0.0001) for intra-observer variability. For sample size variability, ICC values were 0.94 (P<0.0001), 0.95 (P<0.0001), and 0.96 (P<0.0001) for CNFD, CNBD and CNFL. Bland-Altman plots showed excellent agreement for all parameters. Conclusions This study shows that implementing a standardized protocol to select IVCCM images results in high intra and inter-observer reproducibility for all corneal nerve parameters and 6 images are adequate for analysis. IVCCM could therefore be deployed in large multicenter clinical trials with confidence.

UR - http://www.scopus.com/inward/record.url?scp=85027730625&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85027730625&partnerID=8YFLogxK

U2 - 10.1371/journal.pone.0183040

DO - 10.1371/journal.pone.0183040

M3 - Article

VL - 12

JO - PLoS One

JF - PLoS One

SN - 1932-6203

IS - 8

M1 - e0183040

ER -