Biomedical subjects

Yun-An Tsai

Publications and source records attributed to Yun-An Tsai.

6 recordsLinked to original sources

PubMed2004

Loss of sympathetic coordination appears to delay gastrointestinal transit in patients with spinal cord injury.

Patients with spinal cord injury (SCI) often suffer from many gastrointestinal (GI) complaints, while delayed GI transit exists in these patients. We are interested in whether the lost sympathetic activity is one of the mechanisms leading to disturbed GI transit in these subjects. Using a noninvasive hydrogen breath test representing orocecal transit time (OCTT) to study GI transit, 36 SCI patients and 12 age- and sex-matched healthy volunteers were enrolled in our study. Meanwhile, electrocardiogram was performed for all subjects. Finally, spectral analysis of heart rate variability (HRV) was then obtained to assess their sympathovagal balance. SCI patients had higher occurrences of GI symptoms, e.g., nausea/vomiting, belching/hiccup, and constipation, compared to controls (P < 0.05). OCTT was delayed in SCI patients compared to controls (180.8 +/- 10.7 vs 98.3 +/- 14.4 min; P < 0.001). The OCTTs of SCI patients were negatively correlated with their low frequencies of HRV (r = -0.384, P = 0.021). In addition, OCTT was further delayed in quadriplegic patients than paraplegic patients (195.8 +/- 14.5 vs 143.6 +/- 19.4 min; P = 0.031). However, neither the SCI etiology, the injury duration, nor the high frequency of HRV had any influence on the delayed OCTT in SCI patients. We conclude that the GI transit of SCI patients is delayed. This transit disturbance is probably due to loss of sympathetic activity, which is one of the essential components in the coordination of GI peristalsis.

Adult↗

PubMed2004

The challenge of diagnosing psoas abscess.

Diagnosing psoas abscess in patients with low back pain might be hampered by their atypical symptoms. We describe a case in which a 39-year-old retired provost marshal presented to our emergency facility with acute onset of low back pain following an episode of lumbar strain during a flight. His initial computed tomography of lumbar spine and abdominal sonography were inconclusive. Two weeks later, he was admitted to our rehabilitation unit for similar symptoms. One day later, leukocytosis and elevated c-reactive protein following rising body temperature were found. Fever of unknown origin (FUO) was impressed after series of laboratory studies. However, an inflammatory gallium scan performed 2 weeks later due to persistent fever revealed active infection in the L4 vertebra and soft tissue of the L5 paraspinal region. MRI was then performed and demonstrated abnormal enhancement at the bodies of the L2 and L3 vertebrae, prevertebral soft tissue and bilateral psoas muscles. A CT-guided percutaneous aspiration of 10 cc yellowish pus was attained, which yielded no pathogens. His symptoms subsided 1 week after being given appropriate antibiotics. This case showed the importance of nuclear scanning and MRI in patients with low back pain and FUO. It also suggests that repeated imaging study and/or other modality should be considered when the initial imaging result is not compatible with the clinical presentation of psoas abscess, which was initially missed by image studies.

Adult↗

PubMed2003

Neurourological changes before and after radical hysterectomy in patients with cervical cancer.

BACKGROUND: The severity of bladder dysfunction in patients receiving radical hysterectomy for cervical cancer has been related to the delicacy and the degree of radicality of the hysterectomy. Our goal was to evaluate the effect of modified radical hysterectomy on the storage and evacuation of the lower urinary tract. METHODS: In this prospective study, 18 patients underwent radical hysterectomy for cervical cancer with FIGO stages Ia, Ib and IIa. These patients participated in a pudendal motor nerve conduction study and a urodynamic study, including urethral pressure profile (UPP), cystometry (CMG) and uroflowmetry (UFR). These were carried out at preoperative baseline and at 2 weeks, 6 weeks, 3 months and 6 months following surgery. We used generalized linear models to evaluate, over time, the relationship between the different parameters marked in these profiles. RESULTS: The average pudendal nerve motor latency was prolonged at 2 and 6 weeks after surgery but recovered to baseline at 3 months postsurgery. Maximal urethral closing pressure revealed a tendency to decrease, and the CMG showed a significant increase in maximum intravesical filling pressure and a marked decrease in compliance throughout the investigative course. Increased residual urine volume and decreased uroflow rates were detected in a series of UFR. However, these values headed for baseline at 6 months after surgery. CONCLUSION: Transient neurological changes in the majority of our patients suggested that both somatic and autonomic demyelination with or without denervation might be responsible for the temporal changes in vesicourethral function after radical hysterectomy and recovery to baseline condition within 6 months.

Adult↗

PubMed2002

Electrophysiologic findings and muscle strength grading in brachioplexopathies.

The electrophysiological evaluations and the British Medical Research Council (MRC) scale (0-5) findings of target muscles in brachioplexopathies before surgery and 1 year postsurgery were conducted. Each component of the brachial plexus was analyzed in 15 patients with injuries, among them, to 5 roots, 19 trunks, 7 cords, and 13 terminal nerves. In each of these cases, neurolysis and/or nerve transfer and/or neurotization were performed, within 3 weeks to 6 months after the injury was incurred, to ameliorate the resulting severe disabilities. The degrees of impairment were graded using a modified version of Dumitru's and Wilbourn's scale (mild: normal to slight decrease of SNAP amplitude and CMAP amplitude, and occasional denervation; moderate: profound decrease of SNAP amplitude and CMAP amplitude, constant denervation, and normal to slight decrease in motor unit recruitment; severe: absent SNAP amplitude, absent CMAP amplitude, marked denervation, and profound decrease or no volitional motor unit recruitment. mild = 1; moderate = 2; severe = 3). The motor power of the target muscles was graded through MRC scores. The presurgical versus postsurgical differences in the severity of the injury to each brachial plexus component, and differences in the grading of target muscle power, were calculated through the Wilcoxon signed-rank test. The presurgical degrees of the severity of injury, as measured by the electromyography (EMG) were 3.00 +/- 0.00 (mean +/- SD) in root, 2.84 +/- 0.50 in trunk, 3.00 +/- 0.00 in cord, and 2.85 +/- 0.38 in terminal nerves. The postsurgical results were 2.60 +/- 0.55 in root, 2.53 +/- 0.70 in trunk, 2.43 +/- 0.53 in cord, and 1.77 +/- 0.73 in terminal nerves. There was significant improvement at the trunk, cord, and terminal nerve levels after repair, but not at the root levels. Moreover, although the MRC grading showed significant motor recovery in the infraspinatus, deltoid, biceps, and triceps muscles, there was little apparent improvement in the pectoralis major, EDC, APB, and ADM muscles. Nerve repair was notably successful in all plexuses except at the root level. However, our cases demonstrated only poor motor power gains in the forearm and the hand muscles. Consequently, future surgical techniques for brachioplexopathy repairs need further improvement.

Adolescent↗

PubMed2002

The comparison of electrophysiologic findings of traumatic brachial plexopathies in a tertiary care center.

This study was undertaken to demonstrate the distribution of causative factors of brachial plexopathy (BP), to assess the association between the mechanism of injuries and the predominant level of the brachial plexus involved in the injuries, and to characterize the extent and degree of severity of injury in patients with BPI. It consisted of a cross-sectional, retrospective review of electrophysiological data of 5547 patients with 117 patients being identified as having BPI, of whom 86 patients were recruited into the study. The patients were divided into six subgroups according to the mechanism of the damage. The injury was subdivided according to the brachial plexus levels predominantly affected, and each component of the four major anatomical plexus levels-root, trunk, cord and nerve levels was analyzed. The affiliation between the type of injuries and the specified brachial plexus levels was calculated via a two-tailed Fisher's exact test. These findings demonstrated that the type of brachial plexus injury (BPI) is significantly related to the brachial plexus level involved. The motorcycle and birth injury groups were affected at the trunk level, the fall group at the nerve level, the automobile group at the cord level, and the blunt injury group at the cord or nerve level. Moreover, the majority of patients in the motorcycle, fall, and pedestrian groups suffered from severe, incomplete lesions, while the neurophysiological results of the other groups varied.

Accidents, Traffic↗

PubMed2002

A virtual reality-based system for hand function analysis.

The goal of this study was to demonstrate the usability and usefulness of virtual reality technology in assessing hand functions. Ten healthy, non-disabled right-handed adult volunteers were recruited. Each volunteer used a dataglove to insert three-dimensional virtual representations of a cylinder and a prism into the target holes. To verify the reliability of the tests, each subject was retested twice. The performance testing assessed the visual-motor coordination a person needs to achieve a task accurately and within a set time. For each trial, the root mean square (RMS) value of the hand movement trajectory was projected onto the X, Y, and Z axes. This projection enabled us to measure the extent of the genuine, summative displacement of the manipulating hand. The reproducibility of the virtual reality assessment was analyzed using the intraclass correlation (ICC) approach. The total ICC values of 10 subjects demonstrated a high task completion time and RMS on the X and Z axes for the transferring of the prism. However, the values were low for the transferring of the cylinder. Because the individual coefficients of variations (CVs) varied widely in the moving of both the cylinder and the prism, the total (CVs) showed a high reading for the task completion time. Although rehabilitation clinics routinely carry out peg-moving exercises for disabled patients, our model provides a valuable quantitative real time and off-line measure of whole hand functions.

Adult↗