IntroductionGlaucoma is among the leading causes of blindness worldwide. As an optic neuropathy, glaucoma is characterized by progressive retinal ganglion cell death. Elevated intraocular pressure is the only commutable risk factor for glaucoma. However, despite the effective control of intraocular pressure (IOP), the progression of visual field loss suggests that IOP-independent mechanisms may also play a role in glaucomatous degeneration in patients having normal-tension glaucoma (NTG) (1,2).Based on the similarities between glaucoma and neurodegenerative diseases, including the selective loss of neuron populations and common mechanisms of cell injury and death, a contemporary hypothesis has implicated glaucoma as a neurodegenerative disease (3). The IOP-independent mechanisms that cause degeneration in NTG may be similar to the mechanisms at work in neurodegenerative diseases. Some studies have Background/aim: To evaluate, in vivo, the optical coherence tomography (OCT) of the retinal nerve fiber layer (RNFL) and ganglion cell complex (GCC) in patients with normal-tension glaucoma (NTG) and those with Alzheimer disease (AD) in comparison with healthy subjects. Materials and methods:This cross-sectional study included 18 patients with NTG, 20 with AD, and 20 control subjects. An ophthalmologic examination and OCT scans of both eyes were performed in all patients.Results: There was a significant reduction in peripapillary RNFL thickness and macular GCC thickness and a significant increase in the global loss volume (GLV) rate in both the NTG and AD patients when compared to the control subjects (P = 0.004, P = 0.006, P < 0.001, respectively). The statistical evaluation showed no difference in any RNFL or GCC parameters between the AD and NTG groups (P > 0.05). There was a negative correlation between disease duration and average RNFL and GCC thicknesses (r = −0.350, P = 0.027 and r = −0.471, P = 0.002, respectively) and a positive correlation between duration and GLV (r = 0.427, P = 0.006) in the AD group. Conclusion:The average RNFL thickness, GCC thickness, and GLV rates may help in the diagnosis of AD as an additional examination and may provide some important clues about the duration of the disease.

Purpose To investigate the adherence rate of neovascular age-related macular degeneration (nAMD) patients in treat-and-extend (TAE) protocol to their anti-vascular endothelial growth factor (anti-VEGF) intravitreal injection (IVI) appointments and to evaluate the functional and anatomical outcomes of the patients who attended and did not attend their IVI appointments during the coronavirus disease 2019 (COVID-19) restriction period (RP). Methods The patients with nAMD having IVI appointments between March 16 and June 1, 2020 (RP in Turkey) were included in this retrospective study. For adherence analysis, the patients who attended (Group 1, n = 44) and who did not attend (Group 2, n = 60) their IVI appointment visits during the RP ( V RP ) were evaluated according to their last visit before the RP ( V 0 ). For outcome analysis, the patients who attend V RP and have follow-up (Group 1a, 46 eyes) and who did not attend V RP but later attended for follow-up (Group 2a, 33 eyes) were evaluated for functional (best-corrected visual acuity, BCVA [logMAR]) and anatomical (optical coherence tomography [OCT] disease activity) outcomes at the first visit after RP ( V 1 ) and last visit within six months after RP ( V 2 ). Patients received a complete ophthalmologic evaluation with anti-VEGF (Aflibercept) IVI administration at all visits. Results The adherence rate of the patients to V RP was 42.3% (44/104). The patients in Group 1 were significantly younger (mean ± SD years, 71.0 ± 8.1 vs. 74.7 ± 8.0, p = 0.024), had better median [IQR] BCVA at their first presentation (0.30 [0.54] vs. 0.61 [1.08], p = 0.023) and V 0 (0.40 [0.48] vs. 0.52 [0.70], p = 0.031), and had less hypertension (36.4% vs. 58.3%, p = 0.044) than Group 2. The mean ± SD delay of planned IVI at V RP in Group 2a was 13.9 ± 6.2 weeks. Disease activity in OCT was significantly higher in Group 2a than Group 1a at V 1 (60.6% vs. 32.6%, p = 0.025). In Group 2a, the median (IQR) BCVA was significantly worse at V 1 (0.70 [0.58]) and V 2 (0.70 [0.59]) than V 0 (0.52 [0.40], p = 0.047 and p = 0.035, respectively). Conclusions More than half of the scheduled nAMD patients in TAE protocol mi...

To evaluate the effects of the Valsalva manoeuvre (VM) on the choroidal vascularity index (CVI) in healthy volunteers.Methods: This prospective, cross-sectional study included 60 eyes of 30 healthy volunteers. Enhanced depth imaging-optical coherence tomography scans of both eyes involving the fovea were taken, and a 1500 μm subfoveal choroidal area was selected for image binarization with open-access Fiji software. The binarized image was segmented into the stromal area (SA) and luminal area (LA), and CVI was calculated as the ratio (%) of LA to the total choroidal area (TCA). CVI, subfoveal choroidal thickness (SFCT), IOP, systolic and diastolic blood pressure were evaluated at rest and during the VM.Results: During the VM, a mean ± standard deviation increase in LA (0.02 ± 0.05 mm 2 , p < 0.001) and CVI (1.72 ± 2.83%, p < 0.001) was observed, whereas SA (−0.02 ± 0.05 mm 2 , p < 0.001) decreased. There was no significant change in TCA (0.00 ± 0.03 mm 2 , p = 0.55) or SFCT (1.05 ± 10.92 μm, p = 0.46). There was a moderate positive correlation between the spherical equivalent refractive error (SE) and SFCT both at rest and during VM (r 58 = 0.49, p < 0.0005 and r 58 = 0.49, p < 0.0005, respectively). However, there was no significant correlation between SE and CVI either at rest or during VM (p = 0.11 and 0.06, respectively). In a multiple linear regression analysis, CVI was only associated with SFCT; however, SFCT was also associated with SE, both at rest and during VM (p < 0.001). Conclusion: Valsalva manoeuvre increases CVI by choroidal vascular dilation as demonstrated by an increase in LA and a decrease in SA. Researchers should be careful about unintentional VM during examinations. K E Y W O R D S choroidal vascularity index, enhanced depth imaging optical coherence tomography, subfoveal choroidal thickness, Valsalva manoeuvre How to cite this article: Sevik MO, Çam F, Aykut A, Dericioğlu V, Şahin Ö. Choroidal vascularity index changes during the Valsalva manoeuvre in healthy volunteers.

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