Search

Purpose: To evaluate the relationship between peripapillary tilt and visual field (VF) defects in glaucomatous eyes with axial myopia., Study Design: Retrospective cross-sectional study., Patients and Methods: One hundred four eyes of 104 patients with primary open-angle glaucoma (POAG) with myopia were included (52 eyes with high myopia [HM], 26.5 mm ≤ axial length [AL] < 30.0 mm; and 52 eyes without HM, 24.0 mm < AL < 26.5 mm). The direction and magnitude of the peripapillary tilt were evaluated using optical coherence tomography. The eyes were divided into 12 groups according to the tilt directions defined by clock-hour sectors in a clockwise direction in the right eyes and in a counterclockwise direction in the left eyes. The mean deviation (MD) and central VF (CVF) values, ie, the mean threshold values of 4 paracentral points within 5 degrees of the Swedish Interactive Threshold Algorithm 30-2 test, were evaluated., Results: The direction of the tilt was toward sector 9 (47.1%) and sector 8 (34.6%). The MD and CVF values were significantly worse (P = 0.013 and P = 0.019, respectively) in the sector 9 group than in the sector 8 group. Furthermore, the smaller peripapillary tilt magnitude in the sector 9 group was negatively correlated (P = 0.0019) with the CVF but not with the MD (P = 0.1) among the POAG eyes with HM. In contrast, the ovality index in the sector 9 group was not significantly correlated with the MD (P = 0.4) or the CVF (P = 0.36)., Conclusion: A smaller temporal peripapillary tilt correlated with CVF defects in POAG eyes with HM. The peripapillary tilt direction and magnitude affect the CVF defect in POAG eyes with HM.

Purpose: To investigate the corneal biomechanics in eyes with keratectasia following LASIK using a dynamic Scheimpflug analyzer., Design: Case-Control study., Method: The subjects in the study included 12 eyes with keratectasia after LASIK (KE), 24 eyes with keratoconus (KC), 17 eyes without keratectasia after LASIK (LASIK), and 34 eyes with normal corneas (Normal). Corneal biomechanics of the four groups were evaluated using a dynamic Scheimpflug analyzer., Results: Compared with Normal (7.06 ± 0.54), the radius at the highest concavity (radius, mm) of LASIK (5.96 ± 0.76), KE (4.93 ± 0.61) and KC (5.39 ± 1.02) were significantly small. The Deflection Amplitude (HCDLA, mm) of Normal (0.94 ± 0.07) was significantly lower than those of KE (1.11 ± 0.10) and KC (1.06 ± 0.16), and was not significantly different from that of LASIK (0.98 ± 0.07). There were significant differences between LASIK and KE in radius and HCDLA (P < 0.05), whereas KE and KC had no differences in these parameters., Conclusions: Corneal biomechanical features evaluated using the dynamic Scheimpflug analyzer suggest that biomechanical properties in eyes with keratectasia, keratoconus, and LASIK are different from those of normal eyes. Although the biomechanics in eyes with keratectasia differs from that in eyes with LASIK, it is similar to that in eyes with keratoconus.

Purpose: To evaluate the repeatability of corneal deformation parameters measured using a dynamic Scheimpflug analyzer and the impact of baseline clinical factors on the repeatability of each parameter., Study Design: Retrospective, cross-sectional study., Methods: Forty-eight eyes (48 healthy subjects; mean age, 49.0 ± 19.5 years) underwent repeated examinations with the Scheimpflug analyzer to evaluate the test-retest variability. The intraclass correlation coefficient (ICC) and repeatability coefficient as indicators of variability were computed for 35 parameters measured with the Scheimpflug analyzer. The associations between the magnitude of the test-retest variability and baseline factors, such as age, axial length (AL), intraocular pressure (IOP), and central corneal thickness (CCT), were analyzed., Results: The test-retest repeatability was excellent for 22 (62.9%) of 35 parameters (ICC ≥ 0.75), good for seven (20%), (ICC ≥ 0.6), fair for four (11.4%), (ICC ≥ 0.4), and poor for two (5.7%) parameters (ICC < 0.4). Age was associated positively with the magnitude of variability in 13 (37.1%) parameters; measurement variability was affected significantly by AL (5 parameters, 14.3%) and CCT (7 parameters, 20%) but, except for one parameter not by IOP., Conclusion: Most parameters of the dynamic Scheimpflug analyzer showed favorable measurement reliability in healthy subjects. However, six parameters showed poor-to-fair repeatability. Age, AL, and CCT significantly affected the repeatability of several parameters. These results should be considered when clinicians use this device in clinical practice.