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Pao-Sheng Yen

Publications and source records attributed to Pao-Sheng Yen.

12 recordsLinked to original sources
PubMed2006

Unusual magnetic resonance characteristics of a cerebellopontine angle epidermoid cyst with upper cervical spinal canal extension.

We present a 27-year-old woman with an epidermoid cyst at the cerebellopontine (CP) angle with caudal extension into the upper cervical spinal canal. The lesion showed unusual hyperintensity on T1-weighted images, and hypointensity on T2-weighted images. We used microneurosurgical techniques for tumour dissection and excision. To our knowledge, this is the fifth example in Index Medicus/MEDLINE of histopathologically proven CP angle epidermoid with cervical spine extension.

Adult↗
PubMed2006

Microelectrode recording can be a good adjunct in magnetic resonance image-directed subthalamic nucleus deep brain stimulation for parkinsonism.

BACKGROUND: The contribution of MER to improving bilateral STN-DBS is debatable. To resolve the controversy and elucidate the role of MER in DBS, we compared the outcome of bilateral STN-DBS surgery with and without MER in parkinsonian patients. METHODS: From February 2002 to November 2002, the first 7 of 13 consecutive parkinsonian patients received STN-DBS without MER (group A), and the last 6 received STN-DBS with MER (group B). Pre- and postoperative assessments included scoring of UPDRS with video taping, and MR images. RESULTS: The mean Hoehn and Yahr stage was 3.6 in group A and 4.0 in group B. The mean follow-up was 7.4 months for group A and 5.3 months for group B. The mean coordinates of the tip of the permanent electrode relative to the mid-commissural point were x = 8.1 mm, y = 4.3 mm, and z = 5.9 mm for group A and x = 10.6 mm, y = 4.1 mm, and z = 6.9 mm for group B. When levodopa was withdrawn from group A for 12 hours at follow-up, the postoperative UPDRS total score improved by 27.6% (P = .01) and the motor score by 25.4% (P = .02); their LEDD decreased by 17.5% (P = .03). In group B, the postoperative UPDRS total score improved by 49.3% (P = .00002) and the motor score by 45.2% (P = .0004); LEDD decreased by 48.5% (P = .01). CONCLUSIONS: Although STN-DBS is a promising surgical modality for advanced parkinsonian patients, there is an inevitable learning curve associated with adopting this new procedure. Intraoperative MER is an effective way to ensure correct electrode placement in the STN. With the assistance of intraoperative MER, the outcome of STN-DBS can be improved significantly.

Aged↗
PubMed2005

Tophaceous gout of the lumbar spine mimicking infectious spondylodiscitis and epidural abscess: MR imaging findings.

We report a case of surgically proven tophaceous gout of the lumbar spine at the L5-S1 level that mimicked infectious spondylodiscitis and epidural abscess on magnetic resonance (MR) images in a 65-year-old woman. The spinal tophi were hypointense on T1-weighted images; focally and strongly hyperintense on T2-weighted images; and heterogeneously, marginally enhancing on contrast-enhanced T1-weighted images. The aim of this report is to emphasize the importance of considering this disease entity in the differential diagnosis of an epidural mass in a patient with chronic back pain.

Aged↗
PubMed2005

Intravascular lymphomatosis mimicking acute disseminated encephalomyelitis: a case report.

We describe the clinical, radiologic, and postmortem findings in a 49-year-old woman with intravascular lymphomatosis. The patient presented with progressive limb weakness followed by progressive disseminated cerebral neurologic symptoms. Disseminated encephalomyelitis was suspected due to the clinical and radiologic findings. Steroid pulse therapy and intravenous immunoglobulin were given but did not help. The patient died of multiple organ failure 3 months after the onset of symptoms. A diagnosis of disseminated intravascular large B-cell lymphomatosis was established based on findings from histopathology and immunohistochemistry studies on autopsy specimens of the brain and other visceral organs collected postmortem.

Encephalomyelitis, Acute Disseminated↗
PubMed2004

Functional recovery of stroke rats induced by granulocyte colony-stimulating factor-stimulated stem cells.

BACKGROUND: Stroke is a leading cause of death and disability worldwide; however, no effective treatment currently exists. METHODS AND RESULTS: Rats receiving subcutaneous granulocyte colony-stimulating factor (G-CSF) showed less cerebral infarction, as evaluated by MRI, and improved motor performance after right middle cerebral artery ligation than vehicle-treated control rats. Subcutaneous administration of G-CSF enhanced the availability of circulating hematopoietic stem cells to the brain and their capacity for neurogenesis and angiogenesis in rats with cerebral ischemia. CONCLUSIONS: G-CSF induced increases in bone marrow cell mobilization and targeting to the brain, reducing the volume of cerebral infarction and improving neural plasticity and vascularization.

Animals↗
PubMed2004

Primary angiosarcoma of the cranial vault: a case report and review of the literature.

BACKGROUND: Angiosarcoma is a rare neoplasm. It is most likely to affect the scalp in elderly people and involvement of the cranium is uncommon. We report a case of primary malignant angiosarcoma of the cranial vault. CASE DESCRIPTION: An 82-year-old man presented with right hemiparesis, deformity of the cranium and mildly swollen scalp. Further studies disclosed bilateral parietal lesions, with destruction of the dura matter and infiltration of the brain parenchyma. Thrombocytopenia was found. Faint enhancement of the lesions was seen on magnetic resonance imaging (MRI) after i.v. administration of contrast medium with gadolinium. The tumor was excised including the affected portion of the skull and dura matter. Histologic examination revealed typical pictures of angiosarcoma with immunohistochemical evidence of factor VIII-related antigen. Postoperative radiotherapy was employed. The patient remained well at 10 months postoperative follow up. CONCLUSION: Primary angiosarcoma of the cranium is sometimes difficult to differentiate from trauma on clinical examination. We review the literature pertaining to the pathogenesis, clinical course and treatment of this condition. Determination of platelet count may be helpful in monitoring the progression of the disease. The tumor may show faint enhancement on MRI.

Aged↗
PubMed2004

Cough induced by ossification of the ligamentum flavum in the high cervical spine. Case report.

The authors report a very rare case of high cervical ossification of the ligamentum flavum (OLF) in a 40-year-old woman who developed an intractable cough after a traffic accident. The patient's symptoms subsided immediately after decompressive laminectomy and removal of the lesion. To the authors' knowledge, this is the first reported case of high cervical OLF in a patient who presented with a cough. The pathophysiological mechanism underlying the cough was determined to be symptomatic of high cervical spine OLF.

Accidents, Traffic↗
PubMed2003

Imaging of renal tuberculosis in eastern Taiwan: correlation with clinical course and different communities.

Hualien, located in eastern Taiwan, is a relatively isolated district. The population is composed of different ethnic communities. Our hospital is the only medical center in eastern Taiwan, so is the most important referral hospital for epidemic diseases. After reviewing our collected cases of renal tuberculosis (TB), we observed a great diversity in staging and outcomes. The aim of this study was to classify different imaging presentations and clinical outcomes in the ethnic communities represented by these cases (non-aboriginal and aboriginal). We retrospectively reviewed 22 cases from 1991 to 2001. We reviewed laboratory data, radiologic reports, and clinical outcomes. Before TB was proved by biopsy or culture, patients were not treated with an anti-TB regimen. Roentgenography showed that 68% of patients had renal calcification, 59% had dilated calyces, 55% had lung involvement, and 41% had auto-nephrectomy. The proportion of mild and severe forms was significantly different between aboriginal and non-aboriginal groups (0.05 > p > or = 0.00409). From this series, we recommend routine plain film roentgenography, including chest roentgenography and kidney, ureter, and bladder or abdominal roentgenography, followed by intravenous urography or computerized tomography as investigative tools for renal TB. Based on the significantly different outcomes of the disease between aboriginal and non-aboriginal groups, a stronger health education program for the isolated district in eastern Taiwan is necessary.

Antitubercular Agents↗
PubMed2003

Primary medulla oblongata germinoma: a case report and review of the literature.

We describe a case of primary intracranial medulla oblongata germinoma in a 16-year-old girl who presented with progressive headache and blurred vision. Magnetic resonance imaging demonstrated a heterogeneous exophytic mass arising from dorsal aspect of medulla oblongata with extension into fourth ventricle. The differential diagnosis for this patient had included ependymoma, exophytic glioma, medulloblastoma and choroid plexus papilloma. After surgical resection and radiation therapy, she remains alive and recurrence-free for 7 years.

Adolescent↗
PubMed2002

Pseudoaneurysm of the deep circumflex iliac artery: a rare complication at an anterior iliac bone graft donor site treated by coil embolization.

Pseudoaneurysm formation of the deep circumflex iliac artery (DCIA) after harvesting an anterior iliac bone graft for spinal fusion is reported herein. A 76-year-old man with cervical myelopathy underwent anterior cervical decompression and fusion with a left anterior iliac bone graft. A painful left inguinal mass was noted 1 month later. He was admitted to our emergency ward. Angiography of the left external iliac artery was performed which showed a pseudoaneurysm of the DCIA. Selective transarterial coil embolization of the artery was performed, and bleeding was arrested. In a review of the previous literature, only 1 pseudoaneurysm of the DCIA was reported to be associated with anterior iliac bone graft. In conclusion, vascular injury after anterior iliac bone harvesting is rare but can occur. Selective transarterial coil embolization is a prompt and effective solution.

Aged↗