Standardization of corneal haze measurement in confocal microscopy

Jay W. McLaren, William M. Bourne, Sanjay V. Patel

Research output: Contribution to journalArticle

31 Citations (Scopus)

Abstract

PURPOSE. Corneal stromal haze cannot be compared in longitudinal studies or across laboratories without standardization. In this study, a method was devised of standardizing image brightness in confocal microscopy of the cornea. METHODS. Thirty-six normal corneas of 18 untreated volunteers and 35 corneas of 18 patients 3 years after LASIK were examined by slit scanning confocal microscopy. The mean image intensity of each frame was adjusted for daily variations in sensitivity of the microscope by using scans through a solution of Amco Clear (GSF Chemicals, Columbus, OH). Adjusted image intensities were expressed in scatter units (SU), representing the concentration of Amco Clear that produced the same intensity as the image. The intensity from the stroma in corneas after LASIK was compared to that in untreated corneas by using generalized estimating equation models. RESULTS. In the untreated corneas, image brightness was 1079 ± 242 and 758 ± 142 SU in the anterior and mid stroma, respectively. Three years after LASIK, image intensity in the flap was 740 ± 186 SU, approximately 30% lower than in corresponding stroma of the untreated corneas (P < 0.001). At mid stroma, brightness was 715 ± 117 SU after LASIK, and was not significantly different from brightness in untreated corneas (P = 0.26). CONCLUSIONS. Clinical confocal microscopy provides a highresolution measurement of corneal haze, and Amco Clear provides a means of standardizing these measurements. This method can detect subtle decreases in haze in the corneal flap 3 years after LASIK and could be used to examine changes in haze after lamellar keratoplasty.

Original languageEnglish (US)
Pages (from-to)5610-5616
Number of pages7
JournalInvestigative Ophthalmology and Visual Science
Volume51
Issue number11
DOIs
StatePublished - Nov 2010

Fingerprint

Confocal Microscopy
Cornea
Laser In Situ Keratomileusis
Corneal Transplantation
Longitudinal Studies
Volunteers

ASJC Scopus subject areas

  • Ophthalmology
  • Sensory Systems
  • Cellular and Molecular Neuroscience

Cite this

Standardization of corneal haze measurement in confocal microscopy. / McLaren, Jay W.; Bourne, William M.; Patel, Sanjay V.

In: Investigative Ophthalmology and Visual Science, Vol. 51, No. 11, 11.2010, p. 5610-5616.

Research output: Contribution to journalArticle

McLaren, Jay W. ; Bourne, William M. ; Patel, Sanjay V. / Standardization of corneal haze measurement in confocal microscopy. In: Investigative Ophthalmology and Visual Science. 2010 ; Vol. 51, No. 11. pp. 5610-5616.
@article{7eb28eb2802d48bda0ecb8a0fcca7ac1,
title = "Standardization of corneal haze measurement in confocal microscopy",
abstract = "PURPOSE. Corneal stromal haze cannot be compared in longitudinal studies or across laboratories without standardization. In this study, a method was devised of standardizing image brightness in confocal microscopy of the cornea. METHODS. Thirty-six normal corneas of 18 untreated volunteers and 35 corneas of 18 patients 3 years after LASIK were examined by slit scanning confocal microscopy. The mean image intensity of each frame was adjusted for daily variations in sensitivity of the microscope by using scans through a solution of Amco Clear (GSF Chemicals, Columbus, OH). Adjusted image intensities were expressed in scatter units (SU), representing the concentration of Amco Clear that produced the same intensity as the image. The intensity from the stroma in corneas after LASIK was compared to that in untreated corneas by using generalized estimating equation models. RESULTS. In the untreated corneas, image brightness was 1079 ± 242 and 758 ± 142 SU in the anterior and mid stroma, respectively. Three years after LASIK, image intensity in the flap was 740 ± 186 SU, approximately 30{\%} lower than in corresponding stroma of the untreated corneas (P < 0.001). At mid stroma, brightness was 715 ± 117 SU after LASIK, and was not significantly different from brightness in untreated corneas (P = 0.26). CONCLUSIONS. Clinical confocal microscopy provides a highresolution measurement of corneal haze, and Amco Clear provides a means of standardizing these measurements. This method can detect subtle decreases in haze in the corneal flap 3 years after LASIK and could be used to examine changes in haze after lamellar keratoplasty.",
author = "McLaren, {Jay W.} and Bourne, {William M.} and Patel, {Sanjay V.}",
year = "2010",
month = "11",
doi = "10.1167/iovs.10-5614",
language = "English (US)",
volume = "51",
pages = "5610--5616",
journal = "Investigative Ophthalmology and Visual Science",
issn = "0146-0404",
publisher = "Association for Research in Vision and Ophthalmology Inc.",
number = "11",

}

TY - JOUR

T1 - Standardization of corneal haze measurement in confocal microscopy

AU - McLaren, Jay W.

AU - Bourne, William M.

AU - Patel, Sanjay V.

PY - 2010/11

Y1 - 2010/11

N2 - PURPOSE. Corneal stromal haze cannot be compared in longitudinal studies or across laboratories without standardization. In this study, a method was devised of standardizing image brightness in confocal microscopy of the cornea. METHODS. Thirty-six normal corneas of 18 untreated volunteers and 35 corneas of 18 patients 3 years after LASIK were examined by slit scanning confocal microscopy. The mean image intensity of each frame was adjusted for daily variations in sensitivity of the microscope by using scans through a solution of Amco Clear (GSF Chemicals, Columbus, OH). Adjusted image intensities were expressed in scatter units (SU), representing the concentration of Amco Clear that produced the same intensity as the image. The intensity from the stroma in corneas after LASIK was compared to that in untreated corneas by using generalized estimating equation models. RESULTS. In the untreated corneas, image brightness was 1079 ± 242 and 758 ± 142 SU in the anterior and mid stroma, respectively. Three years after LASIK, image intensity in the flap was 740 ± 186 SU, approximately 30% lower than in corresponding stroma of the untreated corneas (P < 0.001). At mid stroma, brightness was 715 ± 117 SU after LASIK, and was not significantly different from brightness in untreated corneas (P = 0.26). CONCLUSIONS. Clinical confocal microscopy provides a highresolution measurement of corneal haze, and Amco Clear provides a means of standardizing these measurements. This method can detect subtle decreases in haze in the corneal flap 3 years after LASIK and could be used to examine changes in haze after lamellar keratoplasty.

AB - PURPOSE. Corneal stromal haze cannot be compared in longitudinal studies or across laboratories without standardization. In this study, a method was devised of standardizing image brightness in confocal microscopy of the cornea. METHODS. Thirty-six normal corneas of 18 untreated volunteers and 35 corneas of 18 patients 3 years after LASIK were examined by slit scanning confocal microscopy. The mean image intensity of each frame was adjusted for daily variations in sensitivity of the microscope by using scans through a solution of Amco Clear (GSF Chemicals, Columbus, OH). Adjusted image intensities were expressed in scatter units (SU), representing the concentration of Amco Clear that produced the same intensity as the image. The intensity from the stroma in corneas after LASIK was compared to that in untreated corneas by using generalized estimating equation models. RESULTS. In the untreated corneas, image brightness was 1079 ± 242 and 758 ± 142 SU in the anterior and mid stroma, respectively. Three years after LASIK, image intensity in the flap was 740 ± 186 SU, approximately 30% lower than in corresponding stroma of the untreated corneas (P < 0.001). At mid stroma, brightness was 715 ± 117 SU after LASIK, and was not significantly different from brightness in untreated corneas (P = 0.26). CONCLUSIONS. Clinical confocal microscopy provides a highresolution measurement of corneal haze, and Amco Clear provides a means of standardizing these measurements. This method can detect subtle decreases in haze in the corneal flap 3 years after LASIK and could be used to examine changes in haze after lamellar keratoplasty.

UR - http://www.scopus.com/inward/record.url?scp=78650851333&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=78650851333&partnerID=8YFLogxK

U2 - 10.1167/iovs.10-5614

DO - 10.1167/iovs.10-5614

M3 - Article

C2 - 20539002

AN - SCOPUS:78650851333

VL - 51

SP - 5610

EP - 5616

JO - Investigative Ophthalmology and Visual Science

JF - Investigative Ophthalmology and Visual Science

SN - 0146-0404

IS - 11

ER -