Correlation of Optic Nerve Microcirculation with Papillomacular Bundle Structure in Treatment Naive Normal Tension Glaucoma

Purpose. To assess the association between optic nerve head (ONH) microcirculation, central papillomacular bundle (CPB) structure, and visual function in eyes with treatment naive normal tension glaucoma (NTG). Methods. This study included 40 eyes of 40 patients with NTG and 20 eyes of 20 normal patients. We used laser speckle flowgraphy (LSFG) to measure mean blur rate (MBR) in all eyes and calculated the ratio of MBR in the horizontal quadrants of tissue area ONH (temporal/nasal ratio of MBR in the tissue area: T/N MT). Clinical findings also included retinal nerve fiber layer thickness (RNFLT) and ganglion cell complex thickness (GCCT) in the CPB and macular areas, best-corrected visual acuity (BCVA), mean deviation (MD), and refractive error. Results. T/N MT was correlated with both BCVA and MD. The OCT parameters most highly correlated with T/N MT were macular RNFLT and mid-CPB RNFLT. Furthermore, T/N MT, mid-CPB RNFLT, and macular RNFLT were higher in NTG than in normal eyes. A discrimination analysis revealed that T/N MT and refractive error were independent factors indicating NTG. Conclusions. Our results suggest that T/N MT is a candidate biomarker of NTG. Furthermore, T/N MT reflects visual function, including acuity and sensitivity, and CPB structure

Correlation between peripapillary macular fiber layer thickness and visual acuity in patients with open-angle glaucoma

Kazuko Omodaka, Toru Nakazawa, Yu Yokoyama, Hiroshi Doi, Nobuo Fuse, Kohji NishidaDepartment of Ophthalmology, Tohoku University Graduate School of Medicine, Aoba-ku, Sendai, Miyagi, JapanPurpose: To determine whether the best-corrected visual acuity (BCVA) is significantly correlated with the retinal nerve fiber layer thickness (RNFLT) in the different peripapillary areas in eyes with open-angle glaucoma (OAG).Patients and methods: Two hundred twenty-nine eyes of 159 patients with OAG were studied. The overall RNFLT and the RNFLT in the superior (S), temporal (T), inferior (I), and nasal (N) quadrants were measured by Stratus optical coherence tomography (OCT). In addition, the temporal RNFLT was measured for three 30° sectors with the mid-temporal (mT) sector at the three or nine o’clock position. The Spearman coefficient of correlation was calculated to determine whether a significant correlation existed between the RNFLT and the BCVA. Eyes with a BCVA < 20/20 were classified as having decreased BCVA. Results: There were significant correlations between the BCVA and the overall RNFLT, and also between the BCVA and the RNFLT in the T, I, and S quadrants. The coefficient correlation between the BCVA and RNFLT was the highest in the mT sector (r = −0.40, P < 0.0001). Forty-eight eyes (21.1%) were classified as having decreased BCVA. The cut-off value of the mT sector for eyes with decreased VA was 39.0 μm.Conclusion: The highest correlation between the BCVA and the RNFLT in the mT sector was most likely due to the location of the maculopapillary bundle in this region of the optic disc. Our findings indicate that when the RNFLT in the mT sector is reduced to 40 μm, glaucoma treatment should be reconsidered.Keywords: retinal nerve fiber layer, low vision, peripapillary macular bundl