Measurement of Normal Optic Nerve Head Parameters Samarawickrama, Chameen, BSc (Med), MBBS; Hong, Thomas, BAppSci, MSc (ClinEpi); Jonas, Jost B., MD ...
Survey of ophthalmology,
07/2012, Letnik:
57, Številka:
4
Journal Article
Recenzirano
Abstract All optic nerve pathologies, including the glaucomas and disorders such as non-arteritic ischemic optic neuropathy, affect the appearance of the optic nerve head. Morphological examination ...of the optic nerve head in a qualitative and quantitative manner is therefore clinically mandatory. With the advent of modern imaging modalities such as confocal scanning laser tomography and optical coherence tomography, new diagnostic avenues have opened up to further refine the examination. The new imaging devices are now becoming a major adjunct to the diagnosis and long-term management of optic nerve head pathology; before it is possible to identify an abnormal optic disk, however, it is essential to understand the morphology and measurement of the normal disk. We summarize recent data on the normal morphology and measurement of optic nerve head parameters as assessed by the major imaging modalities now available.
To compare optic nerve head (ONH) ovality index and rotation angle measurements based on semi-automated delineation of the clinical ONH margin derived from photographs and automated BMO configuration ...derived from optical coherence tomography (OCT) images in healthy and glaucomatous eyes with high-, mild- and no axial myopia.
One hundred seventy-five healthy and glaucomatous eyes of 146 study participants enrolled in the Diagnostic Innovations in Glaucoma Study (DIGS) with optic disc photographs and Spectralis OCT ONH scans acquired on the same day were stratified by level of axial myopia (non-myopic
= 56, axial length (AL) <24 mm, mild-myopic
= 58, AL 24-26 mm and high-myopic
= 32, AL >26 mm. The clinical disc margin of each photograph was manually annotated, and semi-automated measurements were recorded of the ovality index and rotation angle based on a best-fit ellipse generated using ImageJ software. These semi-automated photograph-based measurements were compared to ovality index and rotation angle generated from custom automated BMO-based analysis using segmented OCT ONH volumes.
values from linear mixed effects models were used to describe the associations between semi-automated, photograph-based and automated OCT-based measurements.
Average (95% CI) axial length was 23.3 (23.0, 23.3) mm, 24.8 (24.7, 25.0) mm and 26.8 (26.6, 27.0) mm in non-myopic, mild-myopic and high-myopic eyes, respectively (ANOVA,
≤ 0.001 for all). The
association (95% CI) between semi-automated photograph-based and automated OCT-based assessment of ONH OI for all eyes was 0.26 (0.16, 0.36);
< 0.001. This association was weakest in non-myopic eyes 0.09 (0.01, 0.26);
= 0.02, followed by mild-myopic eyes 0.13 (0.02, 0.29);
= 0.004 and strongest in high-myopic eyes 0.40 (0.19, 0.60);
< 0.001. No significant associations were found between photography- and OCT-based assessment of rotation angle with
values ranging from 0.00 (0.00, 0.08) in non-myopic eyes to 0.03 (0.00, 0.21) in high-myopic eyes (all associations
≥ 0.33).
Agreement between photograph-based and automated OCT-based ONH morphology measurements is limited, suggesting that these methods cannot be used interchangeably for characterizing myopic changes in the ONH.
To investigate the risk and protective factors associated with the retinal nerve fiber layer defect (RNFLD) in a Chinese adult population.
This study was a cross-sectional population-based ...investigation including employees and retirees of a coal mining company in Kailuan City, Hebei Province. All the study participants underwent a comprehensive systemic and ophthalmic examination. RNFLD was diagnosed on fundus photographs. Binary logistic regression was used to investigate the risk and protective factors associated with the RNFLD.
The community-based study included 14 440 participants. There were 10 473 participants in our study, including 7120 males (68.0%) and 3353 females (32.0%). The age range was 45-108y, averaging 59.56±8.66y. Totally 568 participants had RNFLD and the prevalence rate was 5.42%. A higher prevalence of RNFLD was associated with older age
<0.001, odds ratio (OR): 1.032; 95% confidence interval (CI): 1.018-1.046, longer axial length (
=0.010, OR: 1.190; 95%CI: 1.042-1.359), hypertension (
=0.007, OR: 0.639; 95%CI: 0.460-0.887), and diabetes mellitus (
=0.019, OR: 0.684; 95%CI: 0.499-0.939). The protective factors of RNFLD were visual acuity (
=0.038, OR: 0.617; 95%CI: 0.391-0.975), and central anterior chamber depth (
=0.046, OR: 0.595; 95%CI: 0.358-0.990).
In our cross-sectional community-based study, with an age range of 45-108y, RNFLD is associated with older age, longer axial length, hypertension, and diabetes mellitus. The protective factors of RNFLD are visual acuity and central anterior chamber depth. These can help to predict and evaluate RNFLD related diseases and identify high-risk populations early.
Introduction
To examine the compatibility of intravitreally injected epidermal growth factor (EGF) and amphiregulin as EGF family member.
Methods
Four rabbits (age: 4 months; body weight: 2.5 kg) ...received three intravitreal injections of EGF (100 ng) uniocularly in monthly intervals and underwent ocular photography, tonometry, biometry, and optical coherence tomography. After sacrificing the rabbits, the globes were histomorphometrically examined. In a second study part, eyes of 22 guinea pigs (age: 2–3 weeks) received two intravitreal administrations of amphiregulin (10 ng) or phosphate buffered solution (PBS) in 10-day interval, or were left untouched. Ten days after the second injection, the guinea pigs were sacrificed, the enucleated eyes underwent histological and immune-histological examinations.
Results
The rabbit eyes with EGF injections versus the contralateral untouched eyes did not show significant differences in intraocular pressure (7.5 ± 2.4 mmHg vs. 6.8 ± 2.2 mmHg;
P
= 0.66), retinal thickness (158 ± 5 µm vs. 158 ± 3 µm;
P
= 1.0), cell counts in the retinal ganglion cell layer (3.3 ± 1.7 cells/150 µm vs. 3.0 ± 1.4 cells/150 µm;
P
= 0.83), inner nuclear layer (46.4 ± 23.2 cells/150 µm vs. 39.6 ± 6.4 cells/150 µm;
P
= 0.61), and outer nuclear layer (215 ± 108 cells/150 µm vs. 202 ± 47 cells/150 µm;
P
= 0.83), or any apoptotic retinal cells. The guinea pig eyes injected with amphiregulin versus eyes with PBS injections did not differ (
P
= 0.72) in the degree of microglial activation, and both groups did not differ from untouched eyes in number of apoptotic retinal cells and retinal gliosis.
Conclusions
Intravitreal applications of EGF (100 ng) in rabbits nor intravitreal applications of amphiregulin (10 ng) in guinea pigs led to intraocular specific inflammation or any observed intraocular destructive effect. The findings support the notion of a compatibility of intraocular applied EGF and amphiregulin.
Purpose To determine in a population-based study whether parapapillary atrophy is associated with glaucoma. Design Population-based cross-sectional study. Methods The Beijing Eye Study included 4,439 ...of 5,324 subjects invited to participate (response rate, 83.4%). Mean age was 56.2 ± 10.6 years (range, 40 to 101 years). Color optic disk photographs (30 degrees) were examined morphometrically. Parapapillary atrophy was divided into α and β zones. Glaucomatous optic nerve atrophy was defined by a glaucomatous optic nerve head appearance. Results After excluding highly myopic eyes, data from 4,003 (90.2%) subjects entered the statistical analysis. Glaucomatous optic nerve damage was detected in 93 (2.3%) subjects. The β zone of parapapillary atrophy as a whole and measured separately in four disk sectors was significantly larger and occurred significantly more frequently in the glaucomatous group than in the nonglaucomatous group (β zone total area, 1.21 ± 1.92 mm2 vs 0.32 ± 0.99 mm2 ; P < .001). In multiple regression analysis, area of β zone was significantly associated with age ( P < .001), myopic refractive error ( P < .001), and presence of glaucomatous optic nerve damage ( P < .001), with no significant difference between chronic open-angle glaucoma (n = 72) and chronic angle-closure glaucoma (n = 21; β zone area, 1.20 ± 0.39 mm2 vs 1.19 ± 0.46 mm2 ; P = .69). Conclusions In a population-based setting, the β zone of parapapillary atrophy is significantly larger and occurs more frequently in glaucomatous eyes than in normal eyes of Chinese adults, with no marked difference between chronic open-angle glaucoma and primary angle-closure glaucoma.
Purpose
To determine the differences in mean ocular dimensions between urban and rural children and identify possible influencing factors.
Methods
This work uses previously published data from the ...Shandong Children Eye Study, which was based on a random cluster sampling applied to a cross‐sectional school‐based study design in the rural Guanxian County and Weihai city. All children underwent auto‐refractometry and biometry under cycloplegia.
Results
The study included 3290 children (aged 9.35 ± 2.93 years), consisting of 888 pairs of boys and 757 pairs of girls matched by sex, age and refractive error (each pair matching one child from urban cohort with one from the rural cohort). Overall urban children were significantly taller and heavier than rural children (t‐test; p < 0.001), which was confirmed for all age groups for weight. Urban ocular axial lengths were significantly longer by 0.23 mm compared to the rural population (t‐test; p < 0.001), mostly in younger children and boys. Meanwhile, corneal curvatures were flatter in the urban cohort by 0.08 mm (p < 0.001). This association of axial length with urban vs rural region was reduced in magnitude by 69.7% after accounting for height.
Conclusions
For the same, matched refractive error, children from urban regions had significantly longer eyes and flatter corneal curvature than rural children. Since corneal curvature is defined during the first 2 years of life, early environmental factors may be the source of these differences in ocular dimensions.
Along with environmental risk factors such as smoking, hypertension, and atherosclerosis, genetic susceptibility is a primary contributor to the development and progression of exudative age-related ...macular degeneration (AMD). Vascular endothelial growth factor (VEGF) is a central angiogenic regulator and there has been general agreement now that it is an important trigger for the progression of exudative AMD. In the present study, we tested the hypothesis that VEGF gene polymorphisms play a role in the treatment success with VEGF inhibitors in patients with exudative AMD.
Prospective cohort study.
We included 185 eyes of 141 patients with exudative AMD who were scheduled for their first treatment with intravitreally administered bevacizumab in this trial.
All patients were aged >50 years and had angiographically verified exudative AMD. Blood from the finger pad was collected on blood cards for genotyping for the VEGF polymorphisms rs1413711, rs3025039, rs2010963, rs833061, rs699947, rs3024997, and rs1005230. At each follow-up visit, visual acuity was reassessed and an ophthalmic examination was carried out. Visual acuity outcome, number of retreatments, and overall time of treatment were analyzed in dependence of the VEGF polymorphisms.
Mean change in visual acuity at the end of the treatment period.
The included patients were reinjected with bevacizumab 1 to 15 times, resulting in a total treatment period of 42 to 1182 days. In univariate analysis only the G/G genotypes of rs3024997 and rs2010963 compared with all other 5 single nucleotide polymorphisms (SNPs) showed a significantly lower visual acuity at the end of treatment. In multivariate analysis including parameters such as time, baseline visual acuity, and number of reinjections, none of the SNPs showed a significant correlation.
The current study indicates that VEGF polymorphisms are not major predictors of anti-VEGF treatment success in patients with exudative AMD.
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