Excessive Daytime Sleepiness and Injury of the Ascending Reticular Activating System Following Whiplash Injury.

Objectives: This study investigated injuries of the ascending reticular activating system (ARAS) following whiplash injury, in patients with excessive daytime sleepiness (EDS). Methods: Twenty-three patients with whiplash injury and 26 healthy control subjects were recruited for this study. Epworth Sleepiness Scale (ESS) was used for evaluating sleepiness. According to the ESS score, the patients were classified into two groups: subgroup A - ESS score <10, and subgroup B - ESS score ≥10. Three components of the ARAS (lower dorsal, lower ventral, and upper) were evaluated for fractional anisotropy (FA) and tract volume (TV). Results: No significant differences were observed in the FA and TV values of the lower dorsal and upper ARAS between the patient and control groups (p > 0.05). Conversely, the values of FA and TV in the lower ventral ARAS of the patient group were significantly lower than those of the control group (p < 0.05). Comparing the values of subgroups A and B, the TV value of subgroup B was significantly lower than subgroup A (p < 0.05). However, no significant differences were observed in the values of the FA and TV in the lower dorsal and upper ARAS, and the FA value in the lower ventral ARAS (p > 0.05). Conclusions: We found significant injury of the lower ventral ARAS in EDS patients with whiplash injury. These results suggest that diffusion tensor tractography (DTT) could provide useful information for detecting injuries of the ARAS following whiplash injury, in patients with EDS.

Three Dimensional Identification of Medial and Lateral Vestibulospinal Tract in the Human Brain: A Diffusion Tensor Imaging Study.

Purpose: The vestibulospinal tract (VST) is involved in balance control and gait function. No research has identified the VST in the human brain. In the current study, we attempted to identify the medial and lateral VST in the human brain, using diffusion tensor tractography (DTT). Materials and Methods: We recruited 40 healthy volunteers for this study. For reconstruction of the medial VST, a seed region of interest (ROI) was placed on the medial vestibular nuclei in the pons and target ROI on the posteromedial medulla. For reconstruction of the lateral VST, a seed ROI was placed on the lateral vestibular nuclei of pons and the target ROI on the posterolateral medulla. Values of fractional anisotropy (FA), mean diffusivity (MD), and tract volume of the medial and lateral VST were measured. Results: The medial VST, which originates from the medial vestibular nuclei, descends through the posteromedial medulla, and terminates at the anterior funiculus of the cervical spinal cord. The lateral VST originates from the lateral vestibular nuclei, and terminates in the anterior portion of lateral funiculus, through the posterolateral medulla. The FA value of medial VST was significantly higher than that of lateral VST. In contrast, the MD value and tract volume were significantly lower than those of lateral VST (p < 0.05). Conclusion: We identified the medial and lateral VST in the human brain using DTT and investigated the anatomical characteristics of the medial and lateral VST. The methodology and results of this study could be helpful to both clinicians and researchers in the neuroscience field.

The effect of a wrist-hand stretching device for spasticity in chronic hemiparetic stroke patients.

BACKGROUND: The majority of these stretching devices have focused on spasticity of the leg and only a few devices have been developed for spasticity of the wrist and hand. In addition, most of these devices were large and complicated, with less easy applicability for personal use. AIM: To investigate the effect of a stretching device for spasticity of the wrist and hand in chronic hemiparetic stroke patients. DESIGN: Prospective single blind randomized controlled clinical trial. SETTING: Outpatients. METHODS: Patients were randomly assigned to either the intervention group (11 patients) or the control group (10 patients). The stretching device consisted of a circular shaped plastic plate and five holders to immobilize the fingers. In position 1, finger tips were facing forward, position 2 was 90° external rotation from position 1, and position 3 was 90° external rotation from position 2. Each position was maintained for 4 minutes and a rest period of 1 minute was given, therefore, one session was performed for 14 minutes. The stretching program was conducted 3 sessions/day, 6 days/week for 4 weeks. Spasticity (modified Ashworth scale [MAS]) and motor function (Fugl-Meyer motor assessment [FMA], Active Range of Motion [AROM]) of affected wrist and hand were assessed three times (first assessment; Pre, second assessment; post-2 weeks, third assessment; post-4 weeks). RESULTS: In the intervention group, significant differences in the wrist and hand MAS and FMA were observed between three assessment times (P<0.05). However, no significant differences in the wrist and hand AROM were observed between three assessment times (P>0.05). In the control group, no differences in MAS, FMA, and AROM were observed between three assessment times (P>0.05). CONCLUSION: Findings showed that this stretching device was effective in terms of relieving spasticity and functional recovery. CLINICAL REHABILITATION IMPACT: This stretching device is effective in spasticity reducing and motor function improvement. Moreover, it is useful to patient because it is easy to use and portable.