Shang-Yun Ho

Quantitative Ultrasound of the Calcaneus in Hemodialysis Patients

The aim of this study was to investigate the bone status of hemodialysis patients and identify factors that have influence on bone quality. Four hundred eighty-nine subjects (213 males and 276 females) on maintenance hemodialysis and 696 healthy subjects (309 men, 387 women) were enrolled in this study. Speed of sound (SOS), broadband ultrasound attenuation (BUA) and quantitative ultrasound index (QUI) were assessed by quantitative ultrasound (QUS) at the right calcaneus in both groups. Serum levels of intact parathyroid (iPTH), total alkaline phosphatase (ALP), calcium and phosphate were measured to determine their influence on bone status in hemodialysis patients. All QUS parameters were significantly lower in hemodialysis patients than in controls (p < 0.0001). Stepwise multiple linear regression analysis in male patients indicated that age, weight, calcium-phosphate product and ALP were significant predictors of QUS parameters (adjusted R(2) = 0.15 in SOS; adjusted R(2) = 0.17 in BUA and QUI). In female patients, same findings including number of parity were observed in SOS only (adjusted R(2) = 0.25 in SOS). In postmenopausal patients, the duration of menopause was significant negatively correlated with all QUS parameters (p < 0.01). In conclusion, patients on maintenance hemodialysis had additional risk of bone loss. Advanced age, low body weight, high calcium-phosphate product and high ALP level were important risk factors for deterioration of bone quality.

Desmoid Mimicking Cystic Pancreatic Lesion: A Case Report

Desmoid tumors, also called deep or aggressive fibromatosis, are uncommon mesenchymal tumors characterized by proliferation of fibroblasts in an abundant collagen extracellular matrix. They rarely involve the pancreas, and the diagnosis is difficult to make if they do. Only eleven cases have previously been reported involving the pancreas in a review of the literature. In these reported cases, seven patients had solid tumors, three patients had solid tumors with intratumoral cystic components, and only one patient had a cystic tumor. However, the only patient who had a pure cystic tumor was affected with familial adenomatous polyposis (FAP). We herein report an extremely rare case of a sporadic desmoid tumor involving the pancreatic tail, presenting as a cystic lesion. To our knowledge, this is the first reported case of a ＂sporadic＂ desmoid tumor involving the pancreas, presenting as a pure cystic lesion.

Glomus Tumor of the Stomach

Glomus tumors are uncommon submucosal lesions of the stomach. We report a 57-year-old female who developed symptom of tarry stool for one week with initial clinical interpretation as gastric carcinoma by gastroendoscopic study. Finally the tumor was confirmed by microscopic histological study of an endoscopic biopsy specimen as a glomus tumor of the stomach. The sonographic, endoscopic, endosonographic, computed tomography, magnetic resonance image and histologic features of a gastric glomus tumor are reviewed from the literature. Multimodality images can contribute to the pre-operative diagnosis. Correct identification of this essentially benign and uncommon gastric tumor can prevent unnecessary radical operative procedures.

Primary Adenocarcinoma of the Renal Pelvis: A Case Report and Review of the Literature

Neoplasms of the renal pelvis account for approximately 7-8% of all renal malignancies, and most such neoplasms are urothelial in origin. Among these malignancies, the most common type is urothelial carcinoma, followed by squamous cell carcinoma. Primary adenocarcinoma of the renal pelvis is an extremely rare type, with only a few case reports in the literature. It may occur as a result of metaplasia of the renal pelvic transitional epithelium into glandular epithelium due to longstanding obstruction and infection and chronic irritation by urolithiasis, which then undergoes a malignant transformation. Herein, we report a case and the image findings of primary adenocarcinoma of the renal pelvis in a 50-year-old woman with history of renal calculi and end-stage renal disease.

Primary Retroperitoneal Myxofibrosarcoma: a case report and review of the literature

Myxofibrosarcoma is a neoplasm of fibroblastic origin. It commonly occurs in the extremities in the elderly, but rarely arises in the trunk, especially in the retroperitoneum. Herein, we report a rare case and the imaging findings of a primary retroperitoneal myxofibrosarcoma in a 69-year-old male patient without any significant past history who had complained of intermittent abdominal pain and constipation for two months. The imaging studies, including ultrasonography, X-ray of the kidneys, ureter, and bladder (KUB), abdominal computed tomography (CT), and 3.0-Tesla magnetic resonance imaging (MRI), revealed a large well-circumscribed mass lesion arising from the left side of the retroperitoneum. The lesion was filled with great amount of homogenous fluid-like component without prominent calcification or a fat component. After surgical excision, a diagnosis of retroperitoneal myxofibrosarcoma was made. On the follow-up CT obtained ten months after surgery, a local recurrent tumor was observed. Although myxofibrosarcomas rarely arise from the retroperitoneum, the possibility of these tumors should be kept in mind in those patients who have a retroperitoneal lesion with imaging findings similar to that of the tumor.

Evaluation of Coronary Artery Stenosis by Means of Multi-Detector Row Computed Tomography

Multi-detector computed tomography (MDCT) with retrospectively ECG-gated image reconstruction permits coronary artery visualization. The rapid scan time contributes to a high level of patient satisfaction, which facilitates consistent breath-hold even in very ill patients. The fine anatomical structure is visualized by increasing spatial resolution but decreasing slice thickness. The voxel approaches the same size in all three dimensions, which enables high quality 3D image reconstruction. The authors used a 16-slice, with improved spatial, temporal resolution, CT scanner and give β-blocker medication to the patients to lower the heart rate. This helps in the detection of stenosis and occlusions of coronary artery. A total of 235 patients were examined by MDCT within six months. The outcome showed 108 patients with one or more coronary artery stenosis or occlusion. Cardiac MDCT produces images with better signal-to-noise ratio at a thinner slice thickness. Artifacts caused by cardiac motion are the most common problems and may seriously degrade visualization of small anatomic structures. It is tackled by improving temporal resolution or by decreasing the movement of heart. MDCT with retrospective ECG gating permits the detection of coronary artery stenosis with high accuracy, non-invasive and faster means. The examination of cardiac MDCT needs only few minutes, and provides invaluable images for advanced stent implant to treat the stenosis.