Safety and efficacy of mechanical thrombectomy with stent-retrievers in anticoagulated patients with anterior circulation stroke.

AIM: To assess the safety and efficacy of mechanical thrombectomy (MT) with stent-retrievers in anterior circulation stroke (ACS) patients due to the occlusion of major cerebral arteries, and to compare the results achieved in patients on oral anticoagulation (OAC) and those not on OAC. MATERIALS AND METHODS: The present retrospective study comprised 285 consecutive patients (115 males; mean age 74±13 years). The following data were collected: baseline characteristics, occurrence of risk factors, pre-event treatment with OAC, neurological deficit at the time of treatment, time to therapy, recanalisation rate (successful recanalisation defined as Thrombolysis in Cerebral Infarction score ≥2b), post-treatment imaging findings. The 90-day clinical outcome was assessed using modified Rankin scale (good outcome defined as 0-2). RESULTS: The following statistically insignificant differences were found in 26 patients on OAC versus 259 patients without OAC: occurrence of symptomatic intracerebral haemorrhage 7.7% versus 8.1%, achievement of successful recanalisation 69.2% versus 82.6%, good 90-day clinical outcome 34.6% versus 56.8%, 90-day mortality 26.9% versus 20.8% (p>0.05 in all cases). Age and neurological deficit at the time of treatment were identified as independent negative predictors of good 90-day clinical outcome (odds ratio [OR]=0.90, 95% confidence interval [CI]: 0.88-0.94 and OR=0.83, 95% CI: 0.77-0.90, respectively) and as independent positive predictors of mortality (OR=1.12, 95% CI: 1.06-1.18 and, OR=1.17, 95% CI: 1.07-1.27, respectively; p<0.05 in all cases). CONCLUSIONS: MT with stent-retrievers is safe and effective in ACS patients on OAC.

Permutation Entropy and Signal Energy Increase the Accuracy of Neuropathic Change Detection in Needle EMG.

Background and Objective. Needle electromyography can be used to detect the number of changes and morphological changes in motor unit potentials of patients with axonal neuropathy. General mathematical methods of pattern recognition and signal analysis were applied to recognize neuropathic changes. This study validates the possibility of extending and refining turns-amplitude analysis using permutation entropy and signal energy. Methods. In this study, we examined needle electromyography in 40 neuropathic individuals and 40 controls. The number of turns, amplitude between turns, signal energy, and "permutation entropy" were used as features for support vector machine classification. Results. The obtained results proved the superior classification performance of the combinations of all of the above-mentioned features compared to the combinations of fewer features. The lowest accuracy from the tested combinations of features had peak-ratio analysis. Conclusion. Using the combination of permutation entropy with signal energy, number of turns and mean amplitude in SVM classification can be used to refine the diagnosis of polyneuropathies examined by needle electromyography.

Age delays the recovery of distal motor latency after carpal tunnel syndrome surgery.

BACKGROUND: Studies have shown slow healing of peripheral nerve injury in elderly patients. Carpal tunnel syndrome (CTS) is the most frequent compressive mononeuropathy, affecting mostly older people and females. Few studies have assessed electrophysiological differences between younger and older patients. We aimed to evaluate age-dependent differences in electrophysiological parameters preoperatively and postoperatively over a 100-day postoperative period. METHOD: This retrospective study included 258 hands of patients who underwent conventional open-technique carpal tunnel syndrome surgery. Patients with paresthesia in the median nerve distribution or with impaired sensation or abnormal findings in sensory and motor median nerve conduction studies were enrolled. The age dependence of the preoperative values of distal motor latency, amplitude of the compound motor action potential and sensory conduction velocity was estimated using regression analysis. RESULTS: Statistically significant age dependence was found for the preoperative distal motor latency, compound motor action potential, amplitude and sensory conduction velocity. The repair of segmental demyelination was nearly twice as slow in the older group, at a 5 % significance level, even when comparing groups with the same preoperative distal motor latency. CONCLUSIONS: Analysis of preoperative nerve conduction parameters indicates that surgery for carpal tunnel syndrome is performed later in older patients.

[Somatosensoric prosthesis for the blind]. / Somatosenzorická protéza pro slepce.

At present vision prosthesis proposes transmission of only a limited amount of visual information. Cutaneous receptor field may serve as a information channel. It has similar information-processing ability as retina. Lower information capacity of the skin may be compensated by wavelet transform image compression. Advances in microtechnology have facilitated the development of a haptic data visualization system with sufficient life-time for people with visual impairments. Proposed array with 2400 carbon electrodes stewed on elastic membrane in the present experiments demonstrate a good mechanical endurance, electrical stability and adhesivity to the trunk skin. Disadvantageous is short circuits production among near electrodes due to sweating and skin irritation after long term electrical stimulation. Vibrotactile piezo-electric stimulators are safer alternative with lower resolution. Comparing retinal and cortical vision prosthesis offers electrocutaneous communication system comparably higher amount of transmitted information.