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ABSTRACT: The aim of this study was to determine the frequency of metastatic neck nodes detected using sonography in patients with stomach cancer at presentation according to primary subsite and to assess the effect of metastatic neck node detection on tumour staging. Imaging and histological records of 233 patients diagnosed with stomach cancer were reviewed. All patients underwent neck ultrasound at presentation with ultrasound-guided fine needle aspiration for cytology (FNAC) of sonographically abnormal neck nodes. Abnormal nodes were classified positive or negative for metastases based on the FNAC result. Clinical records were also reviewed for evidence of subsequent neck nodal metastases. Sonographically abnormal neck nodes were present in 14/233 (6.0%) patients; 7 were reactive and 7 were metastatic based on FNAC findings and clinical follow-up. Overall, 7/233 (3.0%) patients with stomach cancer had nodal metastases, although tumour stage was altered in only 2/233 (0.9%) patients; 57% of metastatic nodes were impalpable. Nodal metastases from gastric cardia tumours (6%) were more common than from the body (2%) or antrum (3%). Neck node metastases are uncommon in stomach cancer at presentation, are usually associated with extensive intra-abdominal metastatic spread, and adversely influence tumour staging in only a small minority of patients.
European Radiology 04/2009; 19(8):1968-72. · 3.22 Impact Factor
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ABSTRACT: Cross-sectional study.
The purpose of this study was to examine disc morphology and spinal mobility in subjects with varying degrees of osteoporosis.
There was limited information on the effect of osteoporosis on lumbar morphology and spinal mobility. It was also unclear how osteoporosis affects the nonosseous tissues such as the intervertebral disc.
Ninety elderly subjects with varying bone mineral densities (22 normal, 28 osteopenia, 40 osteoporosis) were recruited from an osteoporosis clinic. Lateral radiographs and magnetic resonance images of their lumbar spines were obtained. An electromagnetic tracking device was employed to measure the ranges of motion of the whole lumbar spine.
Although the thoracic spine had been shown to have decreased anterior vertebral body height in subjects with osteoporosis, this study revealed that the anterior height was increased in the lumbar region. Osteoporosis was associated with expansion of the middle of the disc with corresponding collapse of vertebral bodies, but osteoporosis was found not to be related to either disc preservation or degeneration. No significant change in spinal mobility was observed in patients with osteoporosis.
Osteoporosis does not only affect the bone but also the nonosseous tissues. It was found to be associated with expansion of the intervertebral disc, which was likely to be secondary to changes in the vertebral endplate.
Spine 03/2009; 34(3):E115-21. · 2.08 Impact Factor
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ABSTRACT: Peripheral quantitative CT (pQCT) is the main method of bone mineral density (BMD) measurement in small animals. However, pQCT is usually only available in specialized centers, while clinical multidetector computed tomography (MDCT) is much more widely available. This study investigated the feasibility of using clinical 64-slice MDCT for measuring the BMD of rat lumbar vertebrae. The lumbar vertebrae of 18 7-month-old female Sprague-Dawley rats were studied. Two MDCT protocols (General Electric LightSpeed), comprising single 2.5-mm and continuous 0.625-mm acquisitions, and a single pQCT protocol (Scanco Densiscan 2000), comprising 1-mm acquisitions, were performed. The following comparisons were carried out: 2.5-mm MDCT densitometry versus 0.625-mm MDCT densitometry; 0.625-mm MDCT densitometry compared to pQCT densitometry; same day repeatability of 0.625-mm MDCT densitometry; longitudinal repeatability of 0.625-mm MDCT densitometry on day 0 and day 28 and longitudinal 0.625-mm MDCT densitometry in ovariectomized rats on day 0 and day 28. Comparisons were made using intra-class correlation coefficient (ICC). Examination time per animal was 5 min for MDCT and 30 min for pQCT. Acquisitions of 2.5-mm MDCT had a larger coefficient of variation (CoV) than 0.625-mm acquisitions. MDCT densitometry had good agreement with pQCT densitometry (ICC = 0.85). Same-day MDCT densitometry with 0.625-mm acquisitions had a small CoV (1.61%). MDCT densitometry of non-ovariectomized animals at 28 days showed no BMD change, while MDCT densitometry of ovariectomized animals showed a 13.7 +/- 6.7% BMD reduction at 28 days. Clinical MDCT can reliably and accurately measure rat lumbar vertebral BMD and is much faster than pQCT.
European Radiology 11/2008; 19(4):882-90. · 3.22 Impact Factor
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ABSTRACT: The present study employed both static and dynamic imaging modalities to study both intra- and extravascular events attributing to steroid-associated osteonecrosis (ON) using an experimental protocol with a single low-dose lippolysaccharide (LPS) injection and subsequently three injections of high-dose methylprednisolone (MPS).
Fourteen 28-week-old male New Zealand white rabbits received one intravenous injection of LPS (10 microg/kg). After 24 hours, three injections of 20 mg/kg of MPS were given intramuscularly at a time interval of 24 hours. Additional 6 rabbits were used as controls. Dynamic MRI was performed on bilateral femora for local intraosseous perfusion before and after LPS injection. Blood samples were collected for haematological examinations before and after LPS injection. Bilateral femora were dissected and decalcified for microCT-based microangiography. ON lesion, intravascular thrombus and extravascular marrow fat cell size were examined histopathologically.
Intravascular thrombus was observed in all ON rabbits. Extravascular marrow fat cell size was significantly increased in ON rabbits than that of the controls (P < 0.05). Compared to baseline, a significant decrease in ratio of tissue-type-plasminogen-activator/plasminogen-activator inhibitor 1, activated-partial- thromboplatin-time, and a significant increase in ratio of low-density-lipoprotein/high-density-lipoprotein were only found in ON rabbits (P < 0.05). Dynamic MRI showed a significant decrease in the perfusion index 'maximum enhancement' in the ON rabbits (P < 0.05) and microCT-based microangiography showed blocked stem vessels in ON samples. Overall, 93% of the rabbits (13/14) developed ON and no rabbits died throughout the experiment period.
Both intra- and extravascular events were found attributing to the steroid-associated ON based on our experimental protocol with a single low-dose LPS injection and subsequent three injections of high-dose MPS. Both high ON incidence and no mortality in rabbits treated with this inductive protocol suggested its effectiveness for future studies on evaluation of therapeutic efficacy of interventions developed for prevention of steroid-associated ON.
Zhongguo xiu fu chong jian wai ke za zhi = Zhongguo xiufu chongjian waike zazhi = Chinese journal of reparative and reconstructive surgery 03/2008; 22(3):258-64.
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ABSTRACT: The surface method of measuring the movements of lower thoracic and lumbar spine with osteoporosis using Fastrak® was examined for validity. There is an increasing awareness of the health risks of exposure to radiation associated with repeated radiographic assessment of spinal curvature and spinal movements. As a skin-surface measurement device, Fastrak® was employed to study the effect of low bone mineral density on spine motion. However, the reliability and validity of data recorded has not been established. The purpose of this study was to develop a methodology to determine the accuracy of the surface measurement device when it is applied to the motion analysis of osteoporotic spine. The results obtained indicated that the rotation angle of lumbar and lower thoracic spine could be predicted with acceptable accuracy from the data collected from skin-mounted sensors, while the prediction error of translational movements were not acceptable.
Conference proceedings: ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 01/2005; 7:6871-4.
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American Journal of Roentgenology 07/2003; 180(6):1736. · 2.78 Impact Factor
