The Correlations between Recurrent Disc Hemorrhage and Sympathetic Variability, and the Disc Morphology

PURPOSE: To evaluate the correlations of sympathetic variability and recurrent disc hemorrhage, and the morphology of the optic disc. METHODS: This study included 41 eyes of 41 patients who had at least one disc hemorrhage (DH), who were diagnosed with open-angle glaucoma or suspected glaucoma. All eyes had a DH at presentation and were followed-up for at least 3 years. Eyes were classified by the morphology of the optic disc into the focal rim thinning, concentric cupping, or myopic disc groups. The variability of the sympathetic nervous system was defined by the Standard deviation of all node to node intervals (SDNN) as very low frequency, low frequency (LF), or high frequency, which was the standard parameter of heart rate variabilities. RESULTS: There were 14 (34.14%) eyes with a single DH, and the remaining eyes with a recurrent DH. Single DH patients tended to have a myopic disc (p < 0.001) and, especially in the lower 50% of the SDNN group, the recurrent DH group had a lower SDNN (p = 0.046), and a higher LF (p = 0.002). CONCLUSIONS: DH recurred when patients had morphological glaucomatous changes, especially focal rim thinning. Differences of the sympathetic variability had a strong correlation with the recurrent DH.

Changes in Peripapillary Retinal Nerve Fiber Layer Thickness after Pattern Scanning Laser Photocoagulation in Patients with Diabetic Retinopathy

PURPOSE: To examine the effects of panretinal photocoagulation (PRP) using a pattern scanning laser (PASCAL) system on the retinal nerve fiber layer (RNFL) thickness in patients with diabetic retinopathy. METHODS: This retrospective study included 105 eyes with diabetic retinopathy, which consisted of three groups: the PASCAL group that underwent PRP with the PASCAL method (33 eyes), the conventional group that underwent conventional PRP treatment (34 eyes), and the control group that did not receive PRP (38 eyes). The peripapillary RNFL thickness was measured by optical coherence tomography before, six months, and one year after PRP to evaluate the changes in peripapillary RNFL. RESULTS: The RNFL thickness in the PASCAL group did not show a significant difference after six months (average 3.7 times, p = 0.15) or one year after the PRP (average 3.7 times, p = 0.086), whereas that in the conventional group decreased significantly after six months (average 3.4 times, p < 0.001) and one year after PRP (average 3.4 times, p < 0.001). CONCLUSIONS: The results of this study suggest that the PASCAL system may protect against RNFL loss by using less energy than conventional PRP.