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Using laser speckle flowgraphy (LSFG), we investigated the time course of changes in choroidal circulation hemodynamics after a cold pressor test in healthy eyes. This prospective study included the right eye of 19 young healthy participants. The macular mean blur rate (MBR) was measured with LSFG. The MBR, intraocular pressure (IOP), systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), mean blood pressure (MBP), and ocular perfusion pressure (OPP) were evaluated at baseline; immediately after the test and 10, 20, and 30 min later. Immediately after the test (0 min), SBP, DBP, MBP, and OPP were significantly elevated compared with those at baseline. The macular MBR significantly increased by +10.3 ± 7.1% immediately after the test. However, there was no change after 10, 20, and 30 min in the above parameter. A significant positive correlation of the macular MBR with the SBP, MBP, and OPP was observed. In young healthy individuals, increased sympathetic activity induced by a cold pressor test increases choroidal hemodynamics in the macula along with an increase in systemic circulatory dynamics, which normalizes after 10 min. Therefore, LSFG may provide a novel approach for assessing sympathetic activity and intrinsic vascular responsiveness in the eye. [ABSTRACT FROM AUTHOR]

Purpose: The current study aimed to investigate the time course of changes in choroidal circulation hemodynamics and their relationship to systemic circulation dynamics during the normal menstrual cycle in young, healthy women using laser speckle flowgraphy (LSFG). Methods: This prospective study included 26 eyes from 13 young, healthy women (21.3 ± 4.0 years) with a normal menstrual cycle and 24 eyes from 12 young, healthy men (21.8 ± 4.4 years) as a control group. The macular mean blur rate (MBR), a quantitative index of relative blood flow velocity in the choroid, was measured using LSFG. MBR, intraocular pressure (IOP), systolic blood pressure (SBP), diastolic blood pressure (DBP), mean blood pressure (MBP), and ocular perfusion pressure (OPP) were evaluated in the late follicular phase and mid-luteal phase in women and at baseline and 10 days after baseline in men, respectively. Results: In the female group, IOP, SBP, DBP, MBP, and OPP values were significantly higher in the mid-luteal phase than those observed in the late follicular phase (P = 0.035, P < 0.001, P = 0.041, P = 0.001, P = 0.014, respectively). The average macular MBR values in the late follicular phase and mid-luteal phase were 12.7 ± 5.3 and 13.7 ± 6.6 (+7.7 ± 19.4%), representing a significant increase in the mid-luteal phase (P = 0.041). The rate of change in MBR exhibited a significant positive correlation with changes in DBP and MBP (R = 0.456, P = 0.019 and R = 0.474, P = 0.014). However, there were no significant changes in any of the factors in the male group during the study period. Conclusions: Our results suggest that in young, healthy women with a normal menstrual cycle, choroidal blood flow velocity decreases during the late follicular phase and increases during the mid-luteal phase, depending on systemic circulatory dynamics. [ABSTRACT FROM AUTHOR]

Blood pressure (BP) and intraocular pressure (IOP) show seasonal variations. In this prospective study, we measured the IOP, BP, SCT and choroidal blood flow velocity of the right eye of 50 young, healthy volunteers (17 men and 33 women; mean age, 20.7 ± 4.5 years). In healthy participants, systolic BP (SBP), diastolic BP (DBP), MBP, OPP and MBR were significantly higher in winter than in summer. [Extracted from the article]

In an ex vivo rat glaucoma model using dissected retinas, the neurosteroid allopregnanolone (AlloP) protects retinal ganglion cells (RGCs) via GABR/GABAA receptors. To determine the involvement of macroautophagy/autophagy in neuroprotection by AlloP, we examined the effects of autophagy activators, rapamycin and torin 2, and autophagy inhibitors, bafilomycin A1 and SAR405, on retinal retinal morphology and expression of MAP1 LC3B/LC3B (microtubule-associated protein 1 light chain 3 beta) and SQSTM1 (sequestosome 1). Administration of rapamycin or torin 2 exerted partial histological neuroprotection, while combined administration of AlloP with bafilomycin A1 or SAR405 induced severe degeneration in a hyperbaric condition. Electron microscopic analyses showed that the addition of AlloP significantly increased autophagosomes and degenerative autophagic vacuoles in the retinal nerve fiber layer. Immunoblotting showed that the addition of AlloP or autophagic activators increased the lipidated form of LC3B (LC3B-II) and suppressed SQSTM1. Moreover, bafilomycin A1 increased LC3B-II and SQSTM1 protein levels in the presence of AlloP without changes in corresponding mRNAs compared to AlloP-treated retinas in a hyperbaric condition. These data indicate that AlloP likely induces a protective form of autophagy in this model. In an in vivo rat model of glaucoma, we also observed neuroprotective effects of AlloP. Injection of polystyrene microbeads into the anterior chamber increased intraocular pressure about 3-fold and induced RGC apoptosis. A single intravitreal injection of AlloP or autophagy activators prevented apoptosis and protected RGCs with autophagy activation. We conclude that AlloP may serve as a potential therapeutic agent for the treatment of glaucoma via diverse mechanisms. Abbreviations: 2HBCD: 2-Hydroxypropyl)-β-cyclodextrin; 3-MA: 3-methyladenine; AlloP: allopregnanolone; AP: autophagosome; AVd: degradative autophagic vacuoles; GCL: ganglion cell layer; INL: inner nuclear layer; IOP: intraocular pressure; IPL: inner plexiform layer; LC3B-I: cytosolic form of LC3B; LCB-II: lipidated form of LC3B; MAP1LC3B/LC3B: microtubule-associated protein 1 light chain 3 beta; mPTP: mitochondrial permeability transition pore; NDS: neuronal damage score; NFL: nerve fiber layer; OH: ocular hypertension; ON: optic nerve; ONL: outer nuclear layer; OPL: outer plexiform layer; p-STR: scotopic threshold response; RGC: retinal ganglion cells; RT-PCR: real-time reverse transcription polymerase chain reaction; SQSTM1: sequestosome 1; TUNEL: TdT-mediated dUTP Nick End Labeling [ABSTRACT FROM AUTHOR]

Purpose: To report the occurrence probability of disc haemorrhage (DH) and risk factors for it in otherwise healthy Japanese normal‐tension glaucoma (NTG) patients who had lower normal intraocular pressure (IOP) and were followed without treatment for 5 years. Methods: A prospective observational study. Normal‐tension glaucoma (NTG) patients with IOP consistently ≤15 mmHg without treatment were enrolled. The presence or absence of DH was checked semi‐annually on the fundus photographs by three independent observers, while patients were followed without treatment. Cox proportional hazards model taking inter‐eye correlation into consideration was adopted to identify risk factors for DH occurrence. The main outcomes were DH occurrence probability during 5‐year period and its risk factors. Results: One hundred seventeen eyes of 90 patients with mean age of 54.1 years, mean deviation value of −3.6 decibels and mean IOP during follow‐up of 12.4 mmHg were included. Disc haemorrhage (DH) was observed at least once in 34 eyes and more than twice in 15 eyes during the follow‐up. The DH occurrence probability at 5 years was 31% (95% confidence interval: 21–40%), and lower myopic refraction (HR = 1.18; p = 0.018), higher IOP during follow‐up (HR = 1.35; p = 0.047) and presence of DH at baseline (HR = 4.19; p = 0.002) were its risk factors. Conclusion: Disc haemorrhage (DH) occurrence probability of Japanese healthy NTG patients with mean IOP of 12.4 mmHg and no systemic and/or topical treatment was 31% at 5 years. Lower myopic refraction, higher IOP and its existence at baseline were its risk factors. [ABSTRACT FROM AUTHOR]

To characterize the natural history and define the risk factors associated with the progression of normal-tension glaucoma (NTG) in Japanese patients who were followed up closely without treatment. Prospective 5-year study. Patients with NTG with intraocular pressure (IOP) consistently ≤15 mmHg without treatment at baseline. Visual field (VF) examinations were performed every 3 months, and disc/peripapillary retina photographs were taken every 6 months. Patients were followed up without treatment. Deterioration in VF was defined by reference to Guided Progression Analysis Software of the Humphrey VF Swedish Interactive Thresholding Algorithm 24-2 (Carl Zeiss Meditec, Jena, Germany) and disc/peripapillary retina deterioration as adjudged by 3 independent observers. Life table analysis was used for evaluating the time to disease progression, as defined by VF or deterioration of the optic nerve head structure. The Cox proportional hazards model was used to identify risk factors for glaucoma progression. We enrolled 90 patients (mean age, 53.9 years; baseline IOP, 12.3 mmHg; mean deviation [MD], −2.8 decibels [dB]). The MD slope averaged −0.33 dB/year (median, −0.23; 95% confidence interval [CI], −0.44 to −0.22). Glaucoma progression probability at 5 years was 66% (95% CI, 55–78), as defined by VF deterioration or disc/peripapillary retina deterioration (criterion 1): 52% (95% CI, 37–60), as defined by VF deterioration (criterion 2), and 50% (95% CI, 38–71), as defined by disc/peripapillary retina deterioration (criterion 3). Presence or history of disc hemorrhage (DH) (P < 0.001), long-term IOP fluctuation (P = 0.020), and a greater vertical cup-to-disc ratio (v-C/D) (P = 0.018) were significant predictors for progression defined by criterion 1. Long-term IOP fluctuation (P = 0.011) and a greater v-C/D (P = 0.036) were significant predictors for progression by criterion 2. Presence or history of DH (P = 0.0018) and long-term IOP fluctuation (P = 0.022) were significant predictors for progression by criterion 3. In Japanese patients with NTG with mean baseline IOP of 12.3 mmHg without treatment, estimated mean MD slope for 5 years was –0.33 dB/year; probability of glaucoma progression based on VF or disc/peripapillary end points at 5 years was 66%. Presence or history of DH, long-term IOP fluctuation, and greater v-C/D significantly contributed to progression. [ABSTRACT FROM AUTHOR]