Scanning laser polarimetry with variable corneal compensation and optical coherence tomography in normal and glaucomatous eyes

doi:10.1016/S0002-9394(02)02077-9

American Journal of Ophthalmology

Volume 135, Issue 4, April 2003, Pages 521-529

https://doi.org/10.1016/S0002-9394(02)02077-9 Get rights and content

Abstract

Purpose

To evaluate the relationship between visual function and retinal nerve fiber layer (RNFL) measurements obtained with scanning laser polarimetry with variable corneal compensation (SLP-VCC) and optical coherence tomography (OCT).

Design

Cross-sectional analysis of normal and glaucomatous eyes in a tertiary care academic referral practice.

Methods

A commercial GDx nerve fiber analyzer was modified to enable the measurement of corneal polarization axis and magnitude so that compensation for corneal birefringence was eye specific. Complete examination, SLP with fixed corneal compensation (FCC) and variable corneal compensation (VCC), optical coherence tomography (OCT) imaging of the peripapillary RNFL, and automated achromatic perimetry were performed in all subjects. Exclusion criteria were visual acuity less than 20/40, diseases other than glaucoma, and unreliable perimetry.

Results

Fifty-nine patients (59 eyes; 29 normal, 30 glaucomatous) were enrolled (mean age, 56.7 ± 20.3 years, range, 20–91). All eyes with glaucoma had associated visual field loss (average mean defect, −8.4 ± 5.8 dB). Using SLP-FCC, nine of 12 retardation parameters (75%) were significantly less in glaucomatous eyes. Using SLP-VCC, 11of 12 retardation parameters (92%) were significantly less in glaucomatous eyes. Multiple regression models constructed for each retardation parameter with visual field demonstrated that the following VCC parameters were statistically significant whereas FCC parameters were not: ellipse average (FCC, P = .28, VCC, P = .001), superior average (FCC, P = .38, VCC, P < .001), inferior average (FCC, P = .10, VCC, P = .008), average thickness (FCC, P = .30, VCC, P = .031), and superior integral (FCC, P = .43, VCC, P = .001). Similar results were obtained for multiple regression models constructed with OCT-derived RNFL thickness: ellipse average (FCC, P = .99, VCC, P = .002), superior average (FCC, P = .90, VCC, P < .001), inferior average (FCC, P = .61, VCC, P = .007), and superior integral (FCC, P = .92, VCC, P < .001).

Conclusions

Compared with fixed compensation, mean-based SLP parameters generated with SLP-VCC have greater correlation with visual function and RNFL thickness assessments obtained with OCT.

Section snippets

Design

This was a cross-sectional analysis involving normal and glaucomatous eyes.

Methods

Normal and glaucomatous eyes meeting the eligibility criteria were enrolled in this prospective study. Informed consent was obtained from all subjects by means of a consent form approved by the Institutional Review Board for Human Research of the University of Miami School of Medicine. All patients underwent complete ophthalmic examination, including slit-lamp biomicroscopy, gonioscopy, Goldmann applanation tonometry, dilated stereoscopic examination of the optic disk and fundus, achromatic

Results

Fifty-nine patients (59 eyes; 29 normal, 30 glaucomatous) were enrolled (mean age 56.7 ± 20.3 years, range 20–91). All eyes with glaucoma had associated visual field loss (average mean defect, –8.4 ± 5.8 dB). There were no differences between the groups (Table 1) with regard to sex or race, but glaucoma patients were older and had significantly worse (P < .0001) visual field indices.

Eyes with corneal birefringence values that deviated significantly from the fixed compensator had considerable

Discussion

Conventional SLP is limited by marked interindividual variability of the corneal birefringence measurements in the population.21, 22, 23, 25 Greenfield and associates26 have reported a significant increase in the diagnostic precision of the technology by incorporating eye specific corneal polarization axis measurements calculated by a corneal polarimeter into a statistical logistic regression model. The improvement in the discriminating power was especially marked in the five mean-based

References (32)

P.J. Airaksinen et al.
Diffuse and localized nerve fiber loss in glaucoma
Am J Ophthalmol
(1984)
H.A. Quigley et al.
An evaluation of optic disc and nerve fiber layer examinations in monitoring progression of early glaucoma damage
Ophthalmology
(1992)
R.N. Weinreb et al.
Scanning laser polarimetry to measure the nerve fiber layer of normal and glaucomatous eyes
Am J Ophthalmol
(1995)
M.J. Tjon-Fo-Sang et al.
The sensitivity and specificity of nerve fiber layer measurements in glaucoma as determined with scanning laser polarimetry
Am J Ophthalmol
(1997)
J.S. Schuman et al.
Reproducibility of nerve fiber layer thickness measurements using optical coherence tomography
Ophthalmology
(1996)
C. Sanchez-Galeana et al.
Using optical imaging summary data to detect glaucoma
Ophthalmology
(2001)
S.T. Hoh et al.
Optical coherence tomography and scanning laser polarimetry in normal, ocular hypertensive, and glaucomatous eyes
Am J Ophthalmol
(2000)
D.S. Greenfield et al.
Effect of corneal polarization axis on assessment of retinal nerve fiber layer thickness by scanning laser polarimetry
Am J Ophthalmol
(2000)
D.S. Greenfield et al.
Stability of corneal polarization axis measurements for scanning laser polarimetry
Ophthalmology
(2001)
D.S. Greenfield et al.
Correction for corneal polarization axis improves the discriminating power of scanning laser polarimetry
Am J Ophthalmol
(2002)

W.F. Hoyt et al.

Funduscopy of nerve fiber layer defects in glaucoma

Invest Ophthalmol

(1973)

H.A. Quigley et al.

Clinical evaluation of nerve fiber layer atrophy as an indicator of glaucomatous optic nerve damage

Arch Ophthalmol

(1980)

A. Sommer et al.

Clinically detectable nerve fiber layer atrophy precedes the onset of glaucomatous field loss

Arch Ophthalmol

(1991)

R.S. Harwerth et al.

Ganglion cell lossess underlying visual field defects from experimental glaucoma

Invest Ophthalmol Vis Sci

(1999)

S.T. Hoh et al.

Peripapillary nerve fiber layer thickness measurement reproducibility using scanning laser polarimetry

J Glaucoma

(1998)

M.R. Hee et al.

Optical coherence tomography of the human retina

Arch Ophthalmol

(1995)

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This profile is then taken into account to calculate the RNFL retardation after neutralizing eye-specific confounding factors from anterior segment polarization. Use of GDx-VCC demonstrated improved detection of decreased RNFL retardation in glaucomatous eyes compared with GDx-FCC when correlated with visual field function and measurements with OCT [27]. GDx with enhanced corneal compensation (GDx-ECC) was later developed with built-in software changes that accounted for atypical birefringence patterns (ABPs) seen with GDx-VCC.
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One of the recent generation of polarimeters (GDx-VCC), which provides a customized compensation of anterior segment birefringence, has been used for earlier diagnosis of glaucoma [3]. This device has been used to evaluate differences in retardation between normal and glaucomatous eyes and between normal subjects and patients with ocular hypertension (OHTN) [23,24]. GDx VCC has been shown to be effective in differentiating eyes with glaucoma from normals with a sensitivity and specificity >90% [21].
To investigate the prevalence of glaucoma, visual field abnormalities, as well as changes in retinal nerve fiber layer in patients with obstructive sleep apnea syndrome (OSAS).
In this cross-sectional study, 51 patients with OSAS were included. Based on apnea hypopnea index (AHI), there were 26, 6 and 19 cases of severe (AHI ⩾ 30), moderate (15 ⩽ AHI < 30), and mild (5 ⩽ AHI < 15) OSAS, respectively. The control group was matched for age, sex and body mass index. Prevalence of glaucoma and ocular hypertension as well as the following values were assessed and compared between two groups: best-corrected visual acuity, intraocular pressure, central corneal thickness (CCT), cup:disk ratio, mean deviation (MD), pattern standard deviation, and retinal nerve fiber layer (RNFL) parameters using glaucoma diagnosis measurement (GDx).
Seven eyes (6.7%) had intraocular pressure (IOP) > 21 mm Hg; of these, four eyes (3.9%) had glaucoma. No significant difference was detected in CCT between the two groups. IOP was significantly higher in the OSAS group before (p < 0.001) and after (p < 0.001) correcting for CCT. There was a significant difference between groups in MD and most GDx parameters including DISK (temporal–superior–nasal–inferior–temporal) average (p = 0.002), superior average (p = 0.05) and nerve fiber indicator (NFI) (p = 0.03), where those in the patient group showed lower values. There was a significant positive correlation between AHI and both IOP and NFI.
OSAS patients had a higher prevalence of glaucoma and ocular hypertension. OSAS patients also had higher IOP, worse visual field indices, and lower RNFL parameters compared with the control group.
Correlation between Stratus OCT and GDx VCC in early glaucoma, ocular hypertension and glaucoma suspect eyes
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To study the correlation between Stratus optical coherence tomography (OCT) and scanning laser polarimetry (GDx VCC) in measuring retinal nerve fiber layer (RNFL) thickness in eyes with early glaucoma (EG), ocular hypertension (OH), and glaucoma suspect (GS) in a Taiwan Chinese population.
One eye each of 170 subjects (50 eyes with EG, 32 eyes with OH, 38 eyes with GS and 50 healthy eyes) was included. The RNFL thickness was measured by both technologies and three parameters (average, superior and inferior thickness) were correlated using the Pearson's correlation coefficient (r) in each group. Diagnostic capability of two instruments was evaluated in EG, OH and GS eyes based on the area under the receive operator characteristic (AROC) curve.
In healthy and EG eyes, three RNFL parameters were significantly correlated. In OH eye, there was no significant correlation in three parameters. In GS eye, there was significant correlation in inferior thickness only. For healthy vs EG eye, the best parameter with largest AROC was nerve fiber indicator (0.798) for GDx VCC and average thickness (0.787) for OCT. The diagnostic capability of two techniques is poor in OH (AROC, 0.510–0.645) and GS eyes (AROC, 0.510–0.689).
The RNFL thickness measured by OCT and GDx VCC was well correlated in EG and healthy eyes but poorly correlated in OH and GS eyes. When managing the case with OH or GS eye, we should be cautious in interpreting different imaging data.
Estudiar la correlación entre la tomografía de coherencia óptica (OCT) Stratus y la polarimetría láser de barrido (GDx VCC) en la medición del espesor de la capa de fibras nerviosas de la retina (CFNR) en ojos con glaucoma temprano (GT), hipertensión ocular (HO) y sospecha de glaucoma (SG) en una población de chinos taiwaneses.
Se incluyeron 170 sujetos, un ojo de cada uno de ellos (50 ojos con GT, 32 ojos con HO, 38 ojos con SG y 50 ojos sanos). Se midió el espesor de la CFNR con ambas técnicas y se correlacionaron tres parámetros (espesor medio, superior e inferior) utilizando el coeficiente de correlación de Pearson (r) en cada grupo. Se evaluó la capacidad de diagnóstico de ambos instrumentos en ojos con GT, HO y SG basándose en el área bajo la curva de la característica operativa del receptor (AROC).
En ojos sanos y con GT, se correlacionaron de manera significativa tres parámetros de CFNR. En los ojos con HO, no hubo correlación significativa en tres parámetros. En ojos con SG, hubo correlación significativa únicamente en el espesor inferior. Para ojos sanos frente a GT, el mejor parámetro con la mayor AROC fue el indicador de fibras nerviosas (0,798) en GDx VCC y el espesor medio (0,787) en OCT. La capacidad de diagnóstico de ambas técnicas es baja para ojos con HO (AROC: 0,510–0,645) y SG (AROC: 0,510–0,689).
El espesor de la CFNR medido por OCT y GDx VCC presentó una buena correlación en ojos con GT y sanos, pero muy baja en ojos con HO y SG. A la hora de tratar casos de ojos con HO o SG, deberemos ser prudentes al interpretar los diferentes datos de exploraciones por imagen.
Polarization sensitive optical coherence tomography in the human eye
2011, Progress in Retinal and Eye Research
Optical coherence tomography (OCT) has become a well established imaging tool in ophthalmology. The unprecedented depth resolution that is provided by this technique yields valuable information on different ocular tissues ranging from the anterior to the posterior eye segment. Polarization sensitive OCT (PS-OCT) extends the concept of OCT and utilizes the information that is carried by polarized light to obtain additional information on the tissue. Several structures in the eye (e.g. cornea, retinal nerve fiber layer, retinal pigment epithelium) alter the polarization state of the light and show therefore a tissue specific contrast in PS-OCT images. First this review outlines the basic concepts of polarization changing light–tissue interactions and gives a short introduction in PS-OCT instruments for ophthalmic imaging. In a second part a variety of different applications of this technique are presented in ocular imaging that are ranging from the anterior to the posterior eye segment. Finally the benefits of the method for imaging different diseases as, e.g., age related macula degeneration (AMD) or glaucoma is demonstrated.
Relationship between standard automated perimetry and retinal nerve fiber layer parameters measured with laser polarimetry
2010, Archivos de la Sociedad Espanola de Oftalmologia
Determinar la relación entre los parámetros de la capa de fibras nerviosas de la retina (CFNR) obtenidos mediante la polarimetría láser con compensación corneal variable (GDx VCC), y los resultados de la perimetría automatizada convencional (PA) en sujetos normales, hipertensos oculares con glaucomas preperimétricos y glaucomatosos.
423 ojos de 423 sujetos consecutivos fueron prospectivamente incluidos en el estudio y clasificados según los resultados de la presión intraocular basal, PA y morfología papilar en 4 grupos: 87 normales, 192 hipertensos oculares, 70 con glaucoma preperimétrico y 74 glaucomatosos. En los diferentes grupos diagnósticos se calcularon los coeficientes de correlación de Pearson entre la desviación media (DM), la desviación sobre modelo (DSM), el número de puntos alterados en cada uno de los cuadrantes y el número de puntos alterados a diferentes niveles de probabilidad del campo visual con los parámetros de la CFNR obtenidos mediante el GDx VCC. En el grupo de glaucomas se calcularon además las correlaciones entre los 52 puntos que evalúa la estrategia 24-2 SITA Standard y los parámetros del GDx. También se trazaron las curvas de regresión para los parámetros que presentaron las correlaciones más fuertes.
En general las correlaciones estadísticamente significativas fueron escasas y de carácter débil en los sujetos normales, hipertensos oculares y con glaucomas preperimétricos. Sin embargo, el grupo de glaucomas presentó correlaciones de leves a moderadas entre varios parámetros del GDx VCC y las variables del campo visual estudiadas. Las correlaciones más fuertes fueron entre la desviación estándar TSNIT y la DM (0,460) para los índices de la PA y entre el promedio superior y el punto 45 (0,496) para los puntos del campo visual.
Los parámetros de la CFNR medidos con el GDx VCC presentaron correlaciones de débiles a moderadas con los índices del campo visual y el número de puntos alterados por cuadrantes en el grupo de glaucomas.
To determine the relationship between the structural parameters of the retinal nerve fiber layer (RNFL) obtained by using the scanning laser polarimetry with variable corneal compensation (GDx VCC) and the results of standard automated perimetry (SAP), in normal, ocular hypertensive, preperimetric glaucomas and glaucoma subjects.
A total of 423 eyes of 423 consecutive subjects were prospectively included in the study and classified depending on the basal intraocular pressure, optic nerve head appearance and SAP results into four groups: 87 normal eyes, 192 ocular hypertensive eyes, 70 preperimetric glaucomas and 74 glaucomatous eyes. Pearson's correlation coefficients, between mean deviation (MD), pattern standard deviation, number of points altered in each quadrant, and number of points altered at different probability levels of SAP and structural parameters of RNFL obtained by using GDx VCC, were calculated in the different diagnostic groups. In the glaucoma group correlations between the 52 points tested by 24-2 SITA standard and GDx parameters were also calculated. Regression curves were plotted for the strongest correlations.
Weak or non-significant correlations were found in the normal, ocular hypertensive and preperimetric glaucoma groups. However, the glaucoma group presented weak to moderate correlations between several GDx VCC parameters and the SAP variables analysed. The strongest correlation was observed between the standard deviation TSNIT and the MD (0.460).
RNFL parameters measured with the GDx VCC presented weak to moderate correlations with the visual field indices and the number of altered points in the glaucoma group.
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Glaucoma damages the retinal nerve fiber layer (RNFL). The purpose of this study was to investigate the distribution in RNFL of axonal F-actin, a cytoskeletal component, under the development of glaucoma. Intraocular hypertension was induced in a rat model by translimbal laser photocoagulation of the trabecular meshwork. The retinas of control and treated eyes were obtained after different exposures to elevated IOP. Nerve fiber bundles were identified by fluorescent phalloidin staining of F-actin. Nuclei of cell bodies were identified by DAPI fluorescent counterstain. F-actin distribution in whole-mounted retinas was examined by confocal microscopy. En face and cross-sectional images of RNFL were collected around the optic nerve head (ONH). F-actin in normal RNFL was intensely and uniformly stained. In glaucomatous retina, F-actin staining was not uniform within bundles and total loss of F-actin staining was found in severely damaged areas. Altered F-actin often occurred near the ONH in bundles that appeared normal more peripherally. Both alteration and total loss of F-actin were found most often in dorsal retina. In normal RNFL, F-actin is rich and approximately uniformly distributed within nerve fiber bundles. Elevated IOP changes F-actin distribution in RNFL. Topographic features of F-actin alteration suggest that F-actin near the ONH is more sensitive to glaucomatous damage. The alteration pattern also suggests an ONH location for the glaucomatous insult in this rat model.

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^☆: This study was supported in part by the New York Community Trust, New York, New York; a grant from Mr Barney Donnelley, Palm Beach, Florida; and National Institutes of Health Grant R01-EY08684, Bethesda, Maryland. Doctor Greenfield is a member of the Scientific Advisory Board, Laser Diagnostic Technology, San Diego, California.

^☆☆: InternetAdvance publication at ajo.com Jan 6, 2003.

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Scanning laser polarimetry with variable corneal compensation and optical coherence tomography in normal and glaucomatous eyes☆,☆☆

Abstract

Purpose

Design

Methods

Results

Conclusions

Section snippets

Design

Methods

Results

Discussion

Am J Ophthalmol

Ophthalmology

Am J Ophthalmol

Am J Ophthalmol

Ophthalmology

Ophthalmology

Am J Ophthalmol

Am J Ophthalmol

Ophthalmology

Am J Ophthalmol

Funduscopy of nerve fiber layer defects in glaucoma

Invest Ophthalmol

Clinical evaluation of nerve fiber layer atrophy as an indicator of glaucomatous optic nerve damage

Arch Ophthalmol

Clinically detectable nerve fiber layer atrophy precedes the onset of glaucomatous field loss

Arch Ophthalmol

Ganglion cell lossess underlying visual field defects from experimental glaucoma

Invest Ophthalmol Vis Sci

Peripapillary nerve fiber layer thickness measurement reproducibility using scanning laser polarimetry

J Glaucoma

Optical coherence tomography of the human retina

Arch Ophthalmol