BackgroundCurrent visual field screening machines are bulky and expensive, limiting their accessibility, affordability and use. We report the design and evaluation of a novel, portable, cost-effective system for glaucoma screening using smartphone-based visual field screening using frequency doubling technology (FDT) and a head-mounted display.MethodsNineteen eyes of 10 subjects with new-onset or chronic primary open angle glaucoma were tested and compared with the Humphrey Zeiss FDT and the newly developed Mobile Virtual Perimetry (MVP) FDT with the C-20 testing pattern. Mann-Whitney, Bland-Altman and linear regression analyses were performed to assess statistical difference, agreement and correlation, respectively, between the two devices.ResultsThe average age of the participants was 58±15 years. No statistically significant difference was found between the MVP FDT and the Humphrey Zeiss FDT (p>0.05). Bland-Altman and linear regression analyses demonstrated good agreement and correlation between the two devices.ConclusionThe MVP FDT is a low-cost, portable visual field screening device that produces comparable results to the Humphrey Zeiss FDT and may be used as an easily accessible screening tool for glaucoma.

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Purpose: To characterize retinal neurovasculature changes after small-incision lenticule extraction (SMILE) in myopic patients. Setting: Ophthalmic Center, the Second Affiliated Hospital of Guangzhou Medical University, China. Design: Prospective interventional study. Methods: The corrected distance visual acuity/uncorrected distance visual acuity, corrected intraocular pressure (CIOP), and corneal tomography were evaluated at baseline (PRE), postoperative day (POD) 1, and POD 7. Ganglion cell-inner plexiform layer (GCIPL) and peripapillary retinal nerve fiber layer (pRNFL) thicknesses were measured. The vessel area densities (VADs, %), vessel skeleton densities (VSDs, %), vessel diameter index (VDI), and fractal dimensions (Dbox) of the superficial vascular plexus (SVP) and deep vascular plexus (DVP) were measured in a circular area (ϕ 2.5 mm) centered on the fovea. Results: A total of 38 myopic patients were recruited. The GCIPL thickness was increased after SMILE at POD 1 and POD 7 (P < .01) but no significant changes in the pRNFL thickness. The VAD, VSD, and Dbox of the SVP were decreased at POD 1 (P < .01), but not at POD 7. The VDI in small vessels of the SVP and DVP was decreased at POD 1 (P < .05) and increased at POD 7 (P < .05). Changes in CIOP were positively correlated with changes in the GCIPL thickness. Changes in CIOP were negatively correlated with changes in the VAD of small vessels and the Dbox of total vessels in the DVP. Changes in CIOP were negatively correlated with the VSD and VDI of small vessels in the DVP and changes in the VDI of big vessels in the SVP. Conclusions: The transient fluctuations in the retinal neurovasculature after SMILE may represent a characteristic homeostasis pattern in patients after refractive surgery.