Oscillatory neurofeedback networks and poststroke rehabilitative potential in severely impaired stroke patients.

Motor restoration after severe stroke is often limited. However, some of the severely impaired stroke patients may still have a rehabilitative potential. Biomarkers that identify these patients are sparse. Eighteen severely impaired chronic stroke patients with a lack of volitional finger extension participated in an EEG study. During sixty-six trials of kinesthetic motor imagery, a brain-machine interface turned event-related beta-band desynchronization of the ipsilesional sensorimotor cortex into opening of the paralyzed hand by a robotic orthosis. A subgroup of eight patients participated in a subsequent four-week rehabilitation training. Changes of the movement extent were captured with sensors which objectively quantified even discrete improvements of wrist movement. Albeit with the same motor impairment level, patients could be differentiated into two groups, i.e., with and without task-related increase of bilateral cortico-cortical phase synchronization between frontal/premotor and parietal areas. This fronto-parietal integration (FPI) was associated with a significantly higher volitional beta modulation range in the ipsilesional sensorimotor cortex. Following the four-week training, patients with FPI showed significantly higher improvement in wrist movement than those without FPI. Moreover, only the former group improved significantly in the upper extremity Fugl-Meyer-Assessment score. Neurofeedback-related long-range oscillatory coherence may differentiate severely impaired stroke patients with regard to their rehabilitative potential, a finding that needs to be confirmed in larger patient cohorts.

Validation of a community-based survey assessing nonobstetric surgical conditions in Burera District, Rwanda.

BACKGROUND: Validated, community-based surveillance methods to monitor epidemiologic progress in surgery have not yet been employed for surgical capacity building. The goal of this study was to create and assess the validity of a community-based questionnaire collecting data on untreated surgically correctable disease throughout Burera District, Rwanda, to accurately plan for surgical services at a district hospital. METHODS: A structured interview to assess for 10 index surgically treatable conditions was created and underwent local focus group and pilot testing. Using a 2-stage cluster sampling design, Rwandan data collectors conducted the structured interview in 30 villages throughout the Burera District. Rwandan physicians revisited the surveyed households to perform physical examinations on all household members, used as the gold standard to validate the structured interview. RESULTS: A total of 2,990 individuals were surveyed and 2,094 (70%) were available for physical examination. The calculated sensitivity and specificity of the survey tool were 44.5% (95% CI, 38.9-50.2%) and 97.7% (95% CI, 96.9-98.3%), respectively. The conditions with the highest sensitivity and specificity were hydrocephalus, clubfoot, and injuries/infections. Injuries/infections and hernias/hydroceles were the conditions most frequently found on examination that were not reported during the interview. CONCLUSION: This study provides the first attempt to validate a community-based surgical surveillance tool. The finding of low sensitivity was likely related to limited access to care and poor health literacy. Accurate community-based surveys are critical to planning integrated health systems that include surgical care as a core component.