An Electrocorticographic Brain Interface in an Individual with Tetraplegia

Brain-computer interface (BCI) technology aims to help individuals with disability to control assistive devices and reanimate paralyzed limbs. Our study investigated the feasibility of an electrocorticography (ECoG)-based BCI system in an individual with tetraplegia caused by C4 level spinal cord injury. ECoG signals were recorded with a high-density 32-electrode grid over the hand and arm area of the left sensorimotor cortex. The participant was able to voluntarily activate his sensorimotor cortex using attempted movements, with distinct cortical activity patterns for different segments of the upper limb. Using only brain activity, the participant achieved robust control of 3D cursor movement. The ECoG grid was explanted 28 days post-implantation with no adverse effect. This study demonstrates that ECoG signals recorded from the sensorimotor cortex can be used for real-time device control in paralyzed individuals.     

Tetraplegia after coronary artery bypass surgery in a patient with cervical herniation

Tetraplegia is a rare complication after coronary artery bypass surgery. The authors present a case of tetraplegia after uncomplicated coronary artery bypass surgery because of cervical disc herniation. No distinct abnormality was found in the preoperative neurologic examination although the postoperative cervical magnetic resonance imaging revealed a huge hernia at C5-C6 level presenting with tetraplegia. Surgical decompression was performed on the second postoperative day of bypass surgery, and neurologic deficits gradually improved.     

Abdominal Functional Electrical Stimulation to Assist Ventilator Weaning in Acute Tetraplegia: A Cohort Study

Background

Severe impairment of the major respiratory muscles resulting from tetraplegia reduces respiratory function, causing many people with tetraplegia to require mechanical ventilation during the acute stage of injury. Abdominal Functional Electrical Stimulation (AFES) can improve respiratory function in non-ventilated patients with sub-acute and chronic tetraplegia. The aim of this study was to investigate the clinical feasibility of using an AFES training program to improve respiratory function and assist ventilator weaning in acute tetraplegia.

Methods

AFES was applied for between 20 and 40 minutes per day, five times per week on four alternate weeks, with 10 acute ventilator dependent tetraplegic participants. Each participant was matched retrospectively with a ventilator dependent tetraplegic control, based on injury level, age and sex. Tidal Volume (V_T) and Vital Capacity (V_C) were measured weekly, with weaning progress compared to the controls.

Results

Compliance to training sessions was 96.7%. Stimulated V_T was significantly greater than unstimulated V_T. V_T and V_C increased throughout the study, with mean V_C increasing significantly (V_T: 6.2 mL/kg to 7.8 mL/kg V_C: 12.6 mL/kg to 18.7 mL/kg). Intervention participants weaned from mechanical ventilation on average 11 (sd: ± 23) days faster than their matched controls.

Conclusion

The results of this study indicate that AFES is a clinically feasible technique for acute ventilator dependent tetraplegic patients and that this intervention may improve respiratory function and enable faster weaning from mechanical ventilation.

Trial Registration

ClinicalTrials.gov NCT02200393     

Prognosis in tick-borne encephalitis

The paper presents a review of suggested and used methods of predicting the number of the main vector and its infection with the tick-borne encephalitis virus. It has been suggested that most practically important are long-term prognoses of tendencies in the changes of the parasitic system on the basis of retrospective estimation of the recurrence of its changes, that is, the definition of probability of recurrence of most important characters (states) of a parasitic system in the presence of appropriate external conditions.     

Prognosis in aplastic anemia

In catamnestic examinations of patients with aplastic anaemia 11 cases had to be excluded from a primarily diagnosed total number of 112 because these proved to be cases of preleukaemia. In the rest of 101 patients there was a highly significant positive correlation (p less than 0.001) of the survival time to the bone-marrow cellularity and to the average values of corrected reticulocytes and granulocytes calculated from findings of 0,4, and 8 weeks. For thrombocytes, however, a slightly significant positive correlation (p less than 0.05) could only be identified in the present material for the 4-weeks value. The fact that the prognosis is deteriorated by a rapid development of the disease could be made probable by means of a positive correlation between the time of the first symptom and diagnosis (p less than 0.01). With patients falling below 2 or 3 limiting values of the peripheral blood cells they were classified to the SAA group according to the proposals made by Camitta, however, by using the average values described above The survival rate which remained constant after 3 years amounted to 16% for SAA patients classified in this way, 44% for non-SAA cases with constant values of 39% beginning from the fourth year. Patients with average values of all three cell parameters falling below those limiting areas had a six months survival time of only 11%. No patients were alive after one year. The latter was also true if reticulocytes and granulocytes were affected by a diminution of only 2 parameters. Those patients, however, who had an average of reticulocytes and thrombocytes only, but no granulocytes below the limiting area within the first 8 weeks showed a mortality curve which did not differ from that of non-SAA patients. Therefore, a classification of these cases can only be made with great caution allowing for a prognosis-oriented therapy, such as indication for bone-marrow transplantation.