To verify the usefulness of diffusion tensor imaging (DTI) and fiber tractography (FT) compared with routine magnetic resonance imaging (MRI) in patients with cervical spinal cord injury, and to clarify the relationship between motor and sensory impairments and DTI and FT parameters, we performed routine MRI and DTI on 10 patients with chronic cervical spinal cord injury and on 10 controls. Quantitative parameters of DTI, such as fractional anisotropy (FA) and apparent diffusion coefficient (ADC), were calculated for each cervical cord level. FT parameters of imaginary crossing fiber numbers were also determined at the C3 level, from C3–C6, and from C3–C7, as well as each connection rate. All patients' clinical motor and sensory functions were examined using the International Standards for the Neurological Classification of Spinal Cord Injury (ISCSCI). FA values in the controls and patients were 0.76 ± 0.08 (mean ± standard deviation) and 0.58 ± 0.11, respectively, and ADC values in the controls and patients were 1.29 ± 0.75 × 10^–3 mm²/sec and 1.26 ± 0.66 × 10^–3 mm²/sec, respectively. In patients with cervical cord injury, abnormal cervical levels detected on routine MRI were not correlated with clinical findings and DTI parameters, but FA of DTI was correlated with motor function, as were imaginary crossing fiber numbers and connection rates of FT. Quantitative DTI and FT analyses were useful in the evaluation of patients with cervical spinal cord injury. The injured cervical spinal cord can be evaluated in more detail and more precisely using DTI and FT, for which findings are correlated with clinical findings such as neurological impairments.

Motor and sensory deficits after spinal cord injury (SCI) result in functional reorganization of the sensorimotor network. While several task-evoked functional magnetic resonance imaging (fMRI) studies demonstrated functional alteration of the sensorimotor network in SCI, there has been no study of the possible alteration of resting-state functional connectivity using resting-state fMRI. The aim of this study was to investigate the changes of brain functional connectivity in the sensorimotor cortex of patients with SCI. We evaluated the functional connectivity scores between brain areas within the sensorimotor network in 18 patients with SCI and 18 controls. Our findings demonstrated that, compared with control subjects, patients with SCI showed increased functional connectivity between primary motor cortex and other motor areas, such as the supplementary motor area and basal ganglia. However, decreased functional connectivity between primary somatosensory cortex and secondary somatosensory cortex also was found in patients with SCI, compared with controls. These findings therefore demonstrated alteration of the resting-state sensorimotor network in patients with SCI, who showed increased connectivity between motor components, and decreased connectivity between sensory components, within the sensorimotor network, suggesting that motor components within the motor network increased in functional connectivity in order to compensate for motor deficits, whereas the sensory network did not show any such increases or compensation for sensory deficits.

To evaluate clinical features and determine rehabilitation strategies of dysphagia, it is crucial to measure the exact response time of the pharyngeal swallowing reflex in a videofluoroscopic swallowing study (VFSS). However, measuring the response time of the pharyngeal swallowing reflex is labor-intensive and particularly for inexperienced clinicians, it can be difficult to measure the brief instance of the pharyngeal swallowing reflex by VFSS. To accurately measure the response time of the swallowing reflex, we present a novel framework, able to detect quick events. In this study, we evaluated the usefulness of machine learning analysis of a VFSS video for automatic measurement of the response time of a swallowing reflex in a pharyngeal phase. In total, 207 pharyngeal swallowing event clips, extracted from raw VFSS videos, were annotated at the starting point and end point of the pharyngeal swallowing reflex by expert clinicians as ground-truth. To evaluate the performance and generalization ability of our model, fivefold cross-validation was performed. The average success rates of detection of the class “during the swallowing reflex” for the training and validation datasets were 98.2% and 97.5%, respectively. The average difference between the predicted detection and the ground-truth at the starting point and end point of the swallowing reflex was 0.210 and 0.056 s, respectively. Therefore, the response times during pharyngeal swallowing reflex are automatically detected by our novel framework. This framework can be a clinically useful tool for estimating the absence or delayed response time of the swallowing reflex in patients with dysphagia and improving poor inter-rater reliability of evaluation of response time of pharyngeal swallowing reflex between expert and unskilled clinicians.

Lee SH, et al. J Breast Cancer. 2012 Dec;15(4):449-453. http://dx.doi.org/10.4048/jbc.2012.15.4.449

The authors evaluated arm and shoulder function and quality of life prospectively after breast reconstruction with the latissimus dorsi flap. Muscle strength was checked by manual muscle test and range of motion preoperatively and then at five postoperative time points: week 2, week 6, month 3, month 6, and month 12. Functional disability and quality of life were also measured by the Disabilities of the Arm, Shoulder and Hand questionnaire and the 36-Item Short-Form Health Survey. The assessments were performed preoperatively and then at three postoperative time-points (i.e., months 3, 6, and 12). Statistical analysis was performed by repeated-measures analysis of variance. Thirty-one patients were included for analysis. All manual muscle test and range-of-motion scale scores at postoperative week 2 decreased significantly compared with preoperative scores. After postoperative month 3, scores for both manual muscle test and range of motion nearly recovered to preoperative status. However, functional disability, according to the Disabilities of the Arm, Shoulder and Hand instrument, was increased considerably after latissimus dorsi flap surgery, and a substantial amount of disability remained 1 year postoperatively. The mental component of the 36-Item Short-Form Health Survey improved consistently for 1 year postoperatively, whereas the physical component decreased significantly until the sixth month postoperatively and was still lower than the preoperative score at postoperative month 12. One year after latissimus dorsi flap surgery, shoulder strength and range of motion returned to baseline. However, functional disability and deteriorated physical aspects of quality of life persisted.