Pilot Study Assessing the Safety and Acceptance of a Novel Virtual Reality System to Improve Visual Function.

PURPOSE: To assess the feasibility of the clinical use of a novel Virtual Reality (VR) training software designed to be used for active vision therapy in amblyopic patients by determining its preliminary safety and acceptance on the visual function of healthy adults. METHODS: Pilot study enrolling 10 individuals (3 men, 7 women, mean age: 31.8 ± 6.5 years) with a best-corrected visual acuity (BCVA) of ≥ .90 (decimal) in both eyes were evaluated before and after 20 minutes of exposure to the NEIVATECH VR system using the HTC Vive Pro Eye head mounted display. Visual function assessment included near (40 cm) and distance (6 m) cover test (CT), stereopsis, binocular accommodative facility (BAF), near point of convergence (NPC), near point of accommodation (NPA), accommodative-convergence over accommodation (AC/A) ratio and positive and negative fusional vergences. Safety was assessed using the VR Sickness Questionnaire (VRSQ) and acceptance using the Technology Acceptance Model ;(TAM). Changes in all these variables after VR exposure were analyzed. RESULTS: Short-term exposure to the NEIVATECH VR system only induced statistically significant changes in distance phoria (p = .016), but these changes were not clinically relevant. No significant changes were observed in VRSQ oculo-motricity and disorientation scores after exposure (p = .197 and .317, respectively). TAM scores showed a good acceptance of the system in terms of perceived enjoyment and perceived ease of use, although some concerns were raised in relation to the intention-to-use domain. CONCLUSION: Exposure to the NEIVATECH VR system does not seem to adversely affect the visual function in healthy adults and its safety and acceptance profile seems to be adequate for supporting its potential use in other populations, such as amblyopic patients.

Reliability of Potential Pain Biomarkers in the Saliva of Healthy Subjects: Inter-Individual Differences and Intersession Variability.

AIM: Salivary cortisol, α-amylase (sAA), secretory IgA (sIgA), testosterone, and soluble fraction of receptor II of TNFα (sTNFαRII) could serve as objective pain measures, but the normal variability of these potential biomarkers is unknown. PATIENTS & METHODS: Saliva was collected with the passive secretion method from 34, pain-free subjects in two single samples at least 24 hours apart. Biomarker variation and intersession reliability were assessed with the intraclass correlation coefficient (ICC). Also, we calculated the within-subject standard deviation (Sw) and the reproducibility (2.77 × Sw) of intersession measures. RESULTS: Salivary cortisol, sAA, sIgA, testosterone, and sTNFαRII yielded the following ICCs: 0.53, 0.003, 0.88, 0.42 and 0.83, respectively. We found no statistically significant systematic differences between sessions in any biomarker except for testosterone, which showed a decrease on the second day (p<0.001). The reproducibility for salivary cortisol, sAA, sIgA, testosterone, and sTNFαRII were 0.46 ng/ml, 12.88 U/ml, 11.7 µg/ml, 14.54 pg/ml and 18.29 pg/ml, respectively. Cortisol, testosterone and TNFαRII measurement variability showed a positive correlation with the magnitude (p<0.002), but no relationship was found for sAA and sIgA. CONCLUSIONS: Salivary sIgA and sTNFαRII show a remarkable good reproducibility and, therefore, could be useful as pain biomarkers. When using the passive secretion method, intersession variations in salivary sIgA of more than 11.7 µg/ml may reflect true biomarker change. In the case of sTNFαRII this will depend of the magnitude. The estimates herein provided should help investigators and clinicians differentiate actual biomarker modification from measurement variability.

Design and evaluation of a customized reading rehabilitation program for patients with age-related macular degeneration.

PURPOSE: To evaluate the efficacy of a reading rehabilitation program (RRP) specifically designed for patients with impaired central vision from age-related macular degeneration (AMD) and the impact of the program on the quality of life (QoL) and to determine any predictable reading performance improvements between visits. DESIGN: Prospective case series. PARTICIPANTS: Forty-one patients with AMD who attended to the Institute of Applied Ophthalmobiology Eye Institute. METHODS: An ad hoc-created RRP comprising 4 customized in-office training and in-home training visits over 6 weeks was undertaken by AMD patients. The RRP was based on the principle of stepwise progressive goal achievement: the difficulty of training tasks increased depending on the success obtained when performing previous easier ones. Reading performance was evaluated during each in-office training visit, and the individual's perception of his or her QoL was assessed before and after the RRP. Reading performance parameters were assessed to evaluate RRP effectiveness. MAIN OUTCOME MEASURES: Best-corrected visual acuity (BCVA), reading speed, reading duration, near visual acuity (VA), font size, and the World Health Organization Quality of Life (WHOQOL-BREF) questionnaire scores. The effect sizes (mean differences and standard deviations) also were calculated. RESULTS: The mean distance BCVA was 0.81±0.29 logarithm of the minimum angle of resolution units. The mean near VA with the appropriate low-vision aid was 0.91±0.18 (M notation) at baseline. The mean near magnification was 4.32±1.15 at the last in-office visit. The mean reading speed, reading duration, and font size improvement after the reading rehabilitation program were 48.31±22.06 words per minute (P<0.001), 35.46±15.68 minutes (P<0.001), and -4.08±2.19 font points (P<0.001), respectively. The effect sizes of reading speed, reading duration, and font size after the last visit were 2.19, 2.26, and -1.86, respectively. The final score of each WHOQOL-BREF domain improved significantly (P≤0.004) after the RRP. The increased ability to read a smaller font size was correlated with improvement in the physical health domain score of the WHOQOL-BREF (r=0.35; P=0.04). CONCLUSIONS: This customized RRP significantly enhanced reading performance and perceived QoL in patients with AMD. The improvement between visits seemed to be consistent. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.