Ability of Fourier-domain Optical Coherence Tomography to Detect Retinal Ganglion Cell Complex Atrophy in Glaucoma Patients.
ABSTRACT PURPOSE:: To evaluate the diagnostic ability of Fourier-domain optical coherence tomography (FD-OCT) measurements in both normal individuals and patients with different stages of glaucoma. PATIENTS AND METHODS:: A total of 113 patients diagnosed with glaucoma and classified into different stages of glaucoma according to Glaucoma Staging System 2 and 30 healthy individuals were included in this study. In all patients, parameters of both the retinal ganglion cell complex (GCC) and the peripapillary retinal nerve fiber layer were measured by FD-OCT (RTVue-100). Comparisons were made from measurements in patients with different stages of glaucoma. RESULTS:: Both GCC and retinal nerve fiber layer thickness values of patients with glaucoma were statistically significantly lower compared with those of healthy individuals. As the stage of glaucoma progressed, the mean GCC and retinal nerve fiber layer thickness values decreased. CONCLUSIONS:: GCC and retinal nerve fiber layer thickness measurements performed by FD-OCT showed high diagnostic ability in detecting glaucoma. Mean thickness values can be determined for each glaucoma stage.
- [Show abstract] [Hide abstract]
ABSTRACT: This study examines the ability of time domain optical coherence tomography (Stratus OCT) of the retinal nerve fiber layer (RNFL) to discriminate between normal patients and patients with three stages of glaucomatous vision loss in a US veteran population. A review of consecutive patients who underwent automated perimetry and Stratus OCT Fast RNFL scanning within a 6-month period was conducted. Patients with nonglaucomatous ocular disease that might affect the RNFL or perimetry results were excluded. Glaucomatous eyes were staged using the Hodapp-Parrish-Anderson grading system. Average, quadrant, and individual clock hour RNFL thicknesses and normative results between all groups were compared. A total of 247 normal subjects and 157 glaucoma subjects were included. Significant differences in RNFL thickness measurements were observed between all groups (p < 0.05). Receiver operating curve analysis of highest area under the curve showed average RNFL for normal versus mild glaucoma (0.86), inferior quadrant for mild versus moderate glaucoma (0.80), and superior quadrant for moderate versus severe disease (0.86). Normative results for individual parameters demonstrated high specificity but low sensitivity for mild disease versus normal control subjects with increasing sensitivity and decreasing specificity in subsequent stages of disease. The number of OCT parameters classified as borderline or abnormal increased with advancing disease, but a combination of high sensitivity and specificity was not detected for any stage. Optical coherence tomography RNFL thickness measurements, individual parameter normative results, and the number of parameters classified as borderline or abnormal poorly distinguished between severities of disease. Significant RNFL thickness overlap and lack of normative parameters demonstrating both high sensitivity and specificity between consecutive stages of disease highlighted the wide variability of structural findings using time domain OCT in the staging of glaucoma.Optometry and vision science: official publication of the American Academy of Optometry 04/2014; · 1.53 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: To investigate the relationship between scleral mechanical properties, its birefringence, and the anisotropy of birefringence alteration in respect of the direction of the strain by using PS-OCT. The scleral birefringence of thirty-nine porcine eyes was measured with a prototype PS-OCT. A rectangle strip of sclera with a width of 4 mm was dissected at the temporal region 5 mm apart from the optic nerve head. The strain and force were measured with a uniaxial tension tester as the sample was stretched with a speed of 1.8 mm/min after preconditioning. The birefringence of the sample was measured by PS-OCT at the center of the sample before applying, denoted as inherent birefringence, and after applying stretching of 6.5% strain. The birefringence alteration was obtained by these two measurements and correlations between birefringence and elastic parameters, tangent modulus, and structural stiffness were examined. Twenty and 19 porcine eyes were stretched in meridional or equatorial directions, respectively. A moderate positive correlation was found between the inherent birefringence and the structural stiffness. A moderate positive correlation was also found between the inherent birefringence and the tangent modulus. The birefringence increased by strains. Marginal significance was found in the birefringence alteration between meridional and equatorial strains, where the mean birefringence elevation by meridional strain was higher than that by equatorial strain. The birefringence was found to be altered by applying strain and also be related with inherent birefringence. This implies the birefringence of the sclera of the in vivo eye also could be affected by its mechanical property.PLoS ONE 03/2013; 8(3):e58716. · 3.53 Impact Factor