Job-related vision standards have become an increasing concern in recent years. Mobile visual acuity measurements enable early detection and diagnosis of visual impairments and are being used around the world. However, the reliability of mobile visual acuity testing has not yet been fully demonstrated. A simple virtual reality (VR) system combining a mobile phone and a VR cardboard device has the potential as a reliable visual acuity evaluation system due to its fully controlled environment. Visual acuity measurements taken via this type of VR system were evaluated by comparing them with those obtained using the traditional Snellen chart. This study gathered data according to different parameters, including right or left eye, with or without corrective vision devices, and the learning effects of the system. The results showed that the VR system had an accuracy of up to 96.43 and 92.86 for the left and right eyes, respectively, for participants not using corrective devices. In the same group, the proposed system provided significant correlation results for Spearmans r parameters for the left and right eyes (0.7342 and 0.8188, respectively), as compared to those obtained using a traditional approach. Therefore, despite some limitations, a mobile VR system has potential as a self-diagnostic tool for rapid, low-cost visual acuity measurements in a fully controlled environment as well as for providing historical vision data and tracing for the early detection of visual impairments or conditions.

Deep brain stimulation (DBS) improves Parkinson’s disease (PD) symptoms by suppressing neuropathological oscillations. These oscillations are also modulated by inhalational anesthetics used during DBS surgery in some patients, influencing electrode placement accuracy. We sought to evaluate a method that could avoid these effects. We recorded subthalamic nucleus (STN) neuronal firings in 11 PD patients undergoing DBS under inhalational anesthesia. Microelectrode recording (MER) during DBS was collected under median nerve stimulation (MNS) delivered at 5, 20, and 90 Hz frequencies and without MNS. We analyzed the spike firing rate and neuronal activity with power spectral density (PSD), and assessed correlations between the neuronal oscillation parameters and clinical motor outcomes. No patient experienced adverse effects during or after DBS surgery. PSD analysis revealed that peripheral 20 Hz MNS produced significant differences in the dorsal and ventral subthalamic nucleus (STN) between the beta band oscillation (16.9 ± 7.0% versus 13.5 ± 4.8%, respectively) and gamma band oscillation (56.0 ± 13.7% versus 66.3 ± 9.4%, respectively) (p < 0.05). Moreover, 20-Hz MNS entrained neural oscillation over the dorsal STN, which correlated positively with motor disabilities. MNS allowed localization of the sensorimotor STN and identified neural characteristics under inhalational anesthesia. This paradigm may help identify an alternative method to facilitate STN identification and DBS surgery under inhalational anesthesia.

Background/Objectives: To determine whether epidural electrical stimulation (EES) improves sensory recovery and walking function in patients with chronic spinal cord injury (SCI) with a grade on the American Spinal Cord Injury Association impairment scale (AIS) of C or D at the cervical level. Methods: Three individuals with cervical-level chronic AIS D SCI were enrolled in the study. The mean injury duration and age were 4.8 ± 4.5 (range: 1.5–10) and 56.7 ± 9 years, respectively. The participants received personalized electrical stimulation for 36 weeks and were evaluated for their SCI characteristics, the result of an AIS assessment according to the lower extremity sensorimotor scale, their muscle activity, and preoperative walking ability parameters, initially as well as at weeks 8 and 36 of the EES intervention. Results: Participants receiving EES significantly increased the muscle activity in most lower limb muscles. Regarding the AIS assessment of the lower extremities, one participant fully regained a light touch sensation, while two fully recovered their pinprick sensation (AIS sensory scores increased from 14 to 28). One participant achieved a full motor score, whereas the others’ scores increased by 19 and 7 points. Compared with preoperative gait parameters, two participants showed improvements in their walking speed and cadence. Walking symmetry, an important parameter for assessing walking function, improved by 68.7%, 88%, and 77% in the three participants, significantly improving the symmetry index (p = 0.003). Conclusions: Thus, EES may be an effective strategy for sensory impairment recovery, as well as muscular activity and strength improvement. These findings may facilitate stable walking in subjects with chronic incomplete SCI, but larger clinical trials are warranted. Clinical trial: NCT05433064.

Background: Cardiac autonomic neuropathy (CAN) is a common yet frequently underdiagnosed complication of diabetes. While our previous study demonstrated the utility of multiscale cross-approximate entropy (MS-CXApEn) in detecting early CAN, the present study further investigates the use of frequency-domain coherence analysis between systolic blood pressure (SBP) and R-R intervals (RRI) and evaluates the effects of insulin treatment on autonomic function in diabetic rats. Methods: At the onset of diabetes induced by streptozotocin (STZ), rats were assessed for cardiovascular autonomic function both before and after insulin treatment. Spectral and coherence analyses were performed to evaluate baroreflex function and autonomic regulation. Parameters assessed included low-frequency power (LFP) and high-frequency power (HFP) of heart rate variability, coherence between SBP and RRI at low and high-frequency bands (LF_Coh and HF_Coh), spontaneous and phenylephrine-induced baroreflex sensitivity (BRS_spn and BRS_phe), HRV components derived from fast Fourier transform, and MS-CXApEn at multiple scales. Results: Compared to normal controls (LF_Coh: 0.14 ± 0.07, HF_Coh: 0.19 ± 0.06), early diabetic rats exhibited a significant reduction in both LF_Coh (0.08 ± 0.04, p < 0.05) and HF_Coh (0.16 ± 0.10, p > 0.05), indicating impaired autonomic modulation. Insulin treatment led to a recovery of LF_Coh (0.11 ± 0.04) and HF_Coh (0.24 ± 0.12), though differences remained statistically insignificant (p > 0.05 vs. normal). Additionally, low-frequency LFP increased at the onset of diabetes and decreased after insulin therapy in most rats significantly, while MS-CXApEn at all scale levels increased in the early diabetic rats, and MS-CXApEn_large declined following hyperglycemia correction. The BRS_spn and BRS_phe showed no consistent trend. Conclusions: Coherence analysis provides valuable insights into autonomic dysfunction in early diabetes. The significant reduction in LF_Coh in early diabetes supports its role as a potential marker for CAN. Although insulin treatment partially improved coherence, the lack of full recovery suggests persistent autonomic impairment despite glycemic correction. These findings underscore the importance of early detection and long-term management strategies for diabetic CAN.