Objective To observe the therapeutic effect of autologous neurosensory retinal transplantation in repairing unhealed giant macular hole after pars plana vitrectomy (PPV). MethodsA prospective clinical study. From July 2022 to December 2023, 12 patients (12 eyes) with refractory large macular hole who received autologous neurosensory retinal transplantation treatment in Department of Ophthalmology of the First Affiliated Hospital of Zhengzhou University were selected for the study. The macular hole in affected eyes still did not close after PPV combined with inner limiting membrane removal or tamponade, and the diameter of macular hole were greater than 600 μm. All affected eyes received best corrected visual acuity (BCVA) and optical coherence tomography (OCT) examinations. The BCVA examination employed the international standard visual acuity chart, with results converted to logarithm of the minimum angle of resolution (logMAR) visual acuity for statistical analysis. During the surgery, a piece of healthy retinal neuroepithelial tissue, approximately 0.3 optic disc diameters larger than the macular hole, was removed from the upper retinal periphery and used as a graft. The graft was inserted into the macular hole with the aid of intraoperative OCT. Post-surgery, the vitreous cavity was filled with silicone oil or sterile air. The follow-up period after surgery was 6 months. The thickness of the retinal grafts was measured using the same equipment as before surgery at 3 days, 1, 3, and 6 months post-surgery. The primary focus was on observing the macular hole closure rate and changes in BCVA at 6 months post-operation. A paired t-test was used to compare BCVA before and after surgery. Results In the sample of 12 cases (12 eyes), there were 5 males with 5 eyes and 7 females with 7 eyes. The mean age was (50.4±12.6) years. The mean macular hole diameter was (1 085.6±344.0) μm; The mean eye axis length was (27.64±4.19) mm. At 6 months after surgery, all affected eyes showed macular hole were completely closed (100.0%, 12/12). The thickness of the retinal graft was measured as (206.8±21.0), (170.8±23.3), (165.6±31.6), and (157.9±31.1) μm at 3 days, 1, 3, and 6 months post-surgery, respectively. At before and 6 months after surgery, the logMAR BCVA of the affected eyes was 1.28±0.39 and 0.95±0.22, respectively. The difference in logMAR BCVA before and after surgery was statistically significant (t=3.40, P＜0.05). Conclusion Autologous neurosensory retinal transplantation could effectively improve the closure rate of refractory large macular hole and improve or stabilize vision in the short run.
The requirement for unconstrained monitoring of heartbeat during sleep is increasing, but the current detection devices can not meet the requirements of convenience and accuracy. This study designed an unconstrained ballistocardiogram (BCG) detection system using acceleration sensor and developed a heart rate extraction algorithm. BCG is a directional signal which is stronger and less affected by respiratory movements along spine direction than in other directions. In order to measure the BCG signal along spine direction during sleep, a 3-axis acceleration sensor was fixed on the bed to collect the vibration signals caused by heartbeat. An approximate frequency range was firstly assumed by frequency analysis to the BCG signals and segmental filtering was conducted to the original vibration signals within the frequency range. Secondly, to identify the true BCG waveform, the accurate frequency band was obtained by comparison with the theoretical waveform. The J waves were detected by BCG energy waveform and an adaptive threshold method was proposed to extract heart rates by using the information of both amplitude and period. The accuracy and robustness of the BCG detection system proposed and the algorithm developed in this study were confirmed by comparison with electrocardiogram (ECG). The test results of 30 subjects showed a high average accuracy of 99.21% to demonstrate the feasibility of the unconstrained BCG detection method based on vibration acceleration.
Self-powered wearable piezoelectric sensing devices demand flexibility and high voltage electrical properties to meet personalized health and safety management needs. Aiming at the characteristics of piezoceramics with high piezoelectricity and low flexibility, this study designs a high-performance piezoelectric sensor based on multi-phase barium titanate (BTO) flexible piezoceramic film, namely multi-phase BTO sensor. The substrate-less self-supported multi-phase BTO films had excellent flexibility and could be bent 180° at a thickness of 33 μm, and exhibited good bending fatigue resistance in 1 × 104 bending cycles at a thickness of 5 μm. The prepared multi-phase BTO sensor could maintain good piezoelectric stability after 1.2 × 104 piezoelectric cycle tests. Based on the flexibility, high piezoelectricity, wearability, portability and battery-free self-powered characteristics of this sensor, the developed smart mask could monitor the respiratory signals of different frequencies and amplitudes in real time. In addition, by mounting the sensor on the hand or shoulder, different gestures and arm movements could also be detected. In summary, the multi-phase BTO sensor developed in this paper is expected to develop convenient and efficient wearable sensing devices for physiological health and behavioral activity monitoring applications.
Bl factor is a key system parameter of the resonant blood viscoelastic sensor. In this paper, a dynamic measurement system for the spatial distribution of Bl factor based on velocity amplitude and motional impedance was designed. The system extracted the velocity amplitude and motional impedance of the coil under the dynamic condition of driving the sensor to generate simple harmonic oscillations using laser displacement and impedance analysis combined with in-phase/quadrature demodulation algorithm, and controlled the equilibrium position of the coil by adjusting the direct current component of the excitation current to realize the position scanning. In the position interval of [?240, 240] μm, the maximum coefficient of variation of the measurement results was 0.077 3%, and the maximum relative error to the simulation results was 2.937 9%, with a linear fitting correlation coefficient R2 = 0.996 8. The system can be used to accurately measure the spatial distribution of Bl factor of the resonant blood viscoelastic sensor, which provides a technical support for the verification of the design of the sensor magnetic circuit.
Injury of dorsal root ganglia (DRG) may cause sensory and motor dysfunction. In order to investigate the changes of somato-sensory evoked potential (SEP) and histological characteristics of DRG in different causes and different periods of injury, fifty-two rabbits were chosed to build the models. The rabbits were divided into 4 groups: Control group (n = 4); mechanical compressing group (n = 16); inflammatory injury group (n = 16); and treatment group (2% lidocaine with hydroprednisone was administered locally, n = 16). After one to eight weeks, SEP was determined and samples of DRG were obtained to observe the histological and ultrastructural changes every week. The result showed that the gap junction of microvascular endothelium in DRG had been destroyed by the mechanical compression was the major cause of the vessel permeability increasing. The increasing of endothelial pinocytic vesicles transportation and widening of endothelial gap junction were the main causes of inflammatory irritation of DRG. The local infiltration with 2% lidocaine and hydroprednisone could obviously ameliorate inflammatory injury in DRG.
ObjectiveTo investigate the effectiveness of using a sensory prefabricated flap to repair the heel avulsion injury. MethodsBetween August 2012 and August 2013, 6 cases of heel avulsion injury were treated. There were 4 males and 2 females, aged 16-54 years (mean, 29 years). The causes were crush injury in 4 cases and wheel twist injury in 2 cases. The injury to admission time was 2-6 hours (mean, 4 hours). The size of skin avulsion ranged from 5 cm×3 cm to 15 cm×8 cm. Avulsion skin had no replanted condition. At one stage operation, the avulsed heel skin soft tissue was made the full thickness skin graft which was fostered on the anterolateral thigh with lateral circumflex femoral artery perforator, and the lateral femoral cutaneous nerve was put beneath the skin to prefabricate the prefabricated flap; at two stage operation, the prefabricated skin flap pedicled with lateral circumflex femoral artery was used to repair the wound, and the lateral femoral nerve was anastomosed with the calcaneal nerve to reconstruct the feeling. ResultsSix prefabricated flaps all survived, and re-plantation flaps survived after operation. The wounds healed by first intention at donor site and recipient site. The patients were followed up 1-2 years (mean, 1.5 years). The flaps had satisfactory appearance and soft texture. At 1 year after operation, the sensation of the flaps was S3, with two-point discrimination of 22-27 mm (mean, 24.3 mm). According to ZHANG Ming's evaluation standards, the results were excellent in 5 cases, and good in 1 case. The patients could walk normally or with weight-bearing; only linear scar formed at the donor site. ConclusionFor patients with heel soft tissue avulsion injury without replantation qualification, a sensory prefabricated flap by the avulsed heel skin soft tissue can transplanted to repair the heel defect. Satisfactory effectiveness can be obtained in heel appearance and function recovery.
Radiopharmaceutical dynamic imaging typically necessitates intravenous injection via the bolus method. However, manual bolus injection carries the risk of handling errors as well as radiological injuries. Hence, there is potential for automated injection devices to replace manual injection methods. In this study, the effect of micro-bolus pulse injection technology was compared and verified by radioactive experiments using a programmable injection pump, and the overall bubble recognition experiment and rat tail vein simulation injection verification were performed using the piezoelectric sensor preloading method. The results showed that at the same injection peak speed, the effective flushing volume of micro-bolus pulse flushing (about 83 μL/pulse) was 49.65% lower than that of uniform injection and 25.77% lower than that of manual flushing. In order to avoid the dilution effect of long pipe on the volume of liquid, the use of piezoelectric sensor for sealing preloading detection could accurately predict the bubbles of more than 100 μL in the syringe. In the simulated injection experiment of rat tail vein, when the needle was placed in different tissues by preloading 100 μL normal saline, the piezoelectric sensor fed back a large difference in pressure attenuation rate within one second, which was 2.78% in muscle, 17.28% in subcutaneous and 54.71% in vein. Micro-bolus pulse injection method and piezoelectric sensor sealing preloading method have application potential in improving the safety of radiopharmaceutical automatic bolus injection.
Facial complex regional pain syndrome (CRPS) is a CRPS that occurs around the periorbital and/or orofacial region, showing regional chronic pain accompanied by motor and autonomic nervous dysfunction. At present, the pathogenesis of CRPS is not clear, which may include inflammatory reaction, sympathetic nerve, spinal cord, supraspinal and other mechanisms. It is related to the hemisensory disturbances of CRPS, and closely associated with facial allodynia and migraine with trigeminal nerve. This article reviews the possible mechanisms of facial CRPS and connects the limb pain with facial pain, in order to provide some reference for the study of the pathogenesis of CRPS.
OBJECTIVE: To investigate the characteristics and the pathologic classification of electrical-injury nerve using somatosensory evoked potential(SEP) technique. METHODS: SEP were detected and evaluated in 12 cases with electrical-injury nerve during operation, electrical stimulation was commenced from distal side of nerve where the structure of nerve looks normal under operating microscope, up to proximal side until evoking out a stable SEP predeterminate virtual value. Pathological examination and the following functional evaluation were compared with the values of SEP. RESULTS: At the site of nerve looking normal under operating microscope, perineurium appears normal or slightly thicken. But there are obvious fibrosis and fibrotic proliferation between fascicular and intrafascicular. Vessel plexus is not seen. At SEP stabilizely evoked site, nervous construction is normal, there are visible interfascicular vessel plexus and connective tissue appears loose. Comparing SEP values with pathological section, amplitude and latency of SEP is positively correlative with the quality of nerve. Eight cases repaired with SEP technique to select the anastomosis site for nerve transplantation were followed up, two-point discrimination reached grade III (America hand surgery association criterion) within 62.5% cases. CONCLUSION: SEP technique is valuable method for functional evaluation of electrical- injury nerve which has a complicated pathology. The pathology of electrical-injury nerve can be classified into 4 types, type A: fibrosis of nerve; type B: nerve looking normal under operation microscope, perineurium appears thicken, and there are obvious fibrosis and fibrotic proliferation between fascicular and intrafascicular, vessel plexus is rarely to see; type C: nerve looks normal, lymphocyte infiltration exists and it is obvious that there are many physalis-like, retrogressive construction in the section; type D: nervous construction is normal, there are visible interfascicular vessel plexus, and connective tissue appears loose, SEP always can be stably evoked.
Objective To investigate the relationship between graded spinal cord ischemia/reperfusion injury and somatosensory evoked potentials(SEP),neurologic function score（NFS）and the histopathological changes of spinal cord. Methods Forty rabbits were randomized and equally divided into 4 groups: shamoperation group, ischemia for 30min, 45min and 60min groups. The spinal cord ischemiareperfusion injury model was created by occlusion of the abdominal aorta in rabbits. SEP was monitored before ischemia,5,10minutes after ischemia, 15, 30 minutes, 1,2, 24 and 48 hours after reperfusion. NFS was evaluated at 6,12,24 and 48 hours after reperfusion.The pathological changes of spinal cord were observed after reperfusion 48 hours. Results The pathological characters with mild,moderate and severe spinal cord ischemia/reperfusion injury could be simulated by declamping after 30， 45 and 60 minutes infrarenal aorta crossclamping. SEP amplitude returned to normal after reperfusion 15 minutes（Pgt;0.05）and SEP latency returned to normal after reperfusion 30 minutes（Pgt;0.05）during mild spinal cord ischemia/reperfusion injury.SEP amplitude returned to normal after reperfusion 30 minutes（Pgt;0.05）and SEP latency returned to normal after reperfusion 60 minutes（Pgt;0.05）during moderate spinal cord ischemia/reperfusion injury. SEP latency increased and SEP amplitude decreased during severe spinal cord ischemia/reperfusion injury,compared with other groups, there were significant differences in SEP latency and SEP amplitude by clamping the infrarenal aorta for 60min（Plt;0.01）. With graded spinal cord ischemia/reperfusion injury, compared with shamoperation group, spinal cord ischemiareperfusion groups had significant differences in NFS（Plt;0.01）. Conclusion SEP is much quicker in the recovery of amplitude than latency during spinal cord ischemia/reperfusion. SEP is a sensitive and accurate index for spinal cord function during ischemia/reperfusion injury. SEP monitoring spinal cord ischemia/reperfusion injury during operation provides experimental basis for clinical application.