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991.
Kim HJ  Jun BY  Kim WH  Cho YK  Lim MK  Suh CH 《Skeletal radiology》2002,31(11):637-642
OBJECTIVE:. The alar ligament plays a critical role in limiting the axial rotation of the head, the left alar ligament being stretched on rotation to the right and vice versa. The purposes of this study were to assess the usefulness of MR imaging in demonstrating the alar ligament and also to identify its morphologic changes during axial rotation of the head in asymptomatic young volunteers. DESIGN AND PATIENTS:. Twenty-two healthy volunteers participated in this study. All subjects underwent four series of contiguous fast spin echo density-weighted MR images with a 2 mm slice thickness including axial and coronal images with the head in neutral position, and coronal images with alternate head rotation to the right and left. The alar ligaments seen on each series of MR images were visually graded 0-2, and grade comparisons were performed between the four series of MR images. We also assessed the morphologic changes of the alar ligament on coronal images during axial rotation of the head. RESULTS:. Grade comparisons for the demonstration of the alar ligament revealed that each of three series of coronal images was statistically significantly better in grade than axial images. During axial rotation of the head, MR images showed rather constant morphologic changes of the alar ligament: elevation and wrapping of the contralateral alar ligament around the dens, associated with slightly upward movement of C1-C2 on that side. This wrap-around effect of the contralateral alar ligament in relation to the dens sometimes caused the apparent shortening of the alar ligament on that side. CONCLUSION:. Reliable assessment of the anatomy and function of the alar ligament can be achieved with MR imaging, preferably in coronal planes. MR imaging with the aid of a functional study may be a valuable imaging modality in the evaluation of alar ligament failure.  相似文献   
992.
993.
"Seeing inside the body": MR imaging of gene expression   总被引:5,自引:0,他引:5  
The goal of this review is to describe the developments and recent advances that are enabling applications of magnetic resonance (MR) imaging for non-invasive imaging of gene expression. Guiding application of this technology has been the need to test, in vivo and in real time, hypotheses developed in multiple scientific fields. Advances made in the human genome project and our increasing understanding of the molecular basis of normal and disease physiology have defined questions that will only be answered when specific molecular imaging modalities are developed. In this review we will briefly summarize the salient features of MR imaging to provide the backdrop for a more detailed discussion of specific applications of MR imaging of gene expression. We will conclude with the insights gained from genomic approaches and how they might be exploited for MR imaging of gene expression in the future.  相似文献   
994.
New frontiers in CT imaging of airway disease   总被引:7,自引:0,他引:7  
Combining helical volumetric CT acquisition and thin-slice thickness during breath hold provides an accurate assessment of both focal and diffuse airway diseases. With multiple detector rows, compared with single-slice helical CT, multislice CT can cover a greater volume, during a simple breath hold, and with better longitudinal and in-plane spatial resolution and improved temporal resolution. The result in data set allows the generation of superior multiplanar and 3D images of the airways, including those obtained from techniques developed specifically for airway imaging, such as virtual bronchography and virtual bronchoscopy. Complementary CT evaluation at suspended or continuous full expiration is mandatory to detect air trapping that is a key finding for depicting an obstruction on the small airways. Indications for CT evaluation of the airways include: (a) detection of endobronchial lesions in patients with an unexplained hemoptysis; (b) evaluation of extent of tracheobronchial stenosis for planning treatment and follow-up; (c) detection of congenital airway anomalies revealed by hemoptysis or recurrent infection; (d) detection of postinfectious or postoperative airway fistula or dehiscence; and (e) diagnosis and assessment of extent of bronchiectasis and small airway disease. Improvement in image analysis technique and the use of spirometrically control of lung volume acquisition have made possible accurate and reproducible quantitative assessment of airway wall and lumen areas and lung density. This contributes to better insights in physiopathology of obstructive lung disease, particularly in chronic obstructive pulmonary disease and asthma.  相似文献   
995.
Introduction Idiopathic granulomatous mastitis (IGM) is a rare benign inflammatory breast disease that presents with variable local manifestations. We describe here the different management protocols based on the clinical presentation of these patients. Methods A retrospective review of 20 histopathologic confirmed cases of IGM seen over a period of 10 years was performed. Results The median age was 34 years (age range: 21–45 years). All were married, parous with history of breast feeding. Ill-defined mass mimicking carcinoma was the commonest presentation (70%); however, with the presence of signs of inflammation like pain (55%), redness (40%), and peau d’orange (40%), an inflammatory process appeared more likely. Axillary lymph node enlargement was infrequently seen (40%). Radiologic findings (mammography and ultrasound) were nonspecific. Histopathology showed the characteristic lobular distribution of granulomatous inflammation in all cases. Surgically, 7 patients had abscess drainage with open biopsy, and 7 patients had lumpectomy. Six patients with diffuse breast involvement were diagnosed by core needle biopsy only. Microbial cultures showed no growth. Antibiotics were given empirically when signs of inflammation where present. Two patients needed further abscess drainage followed by persistent sinus excision 3–6 weeks later. The median follow-up was 24 months (range: 15–42 months). Seventeen patients (85%) were recurrence-free, and 3 patients (15%) were lost to follow-up. Conclusions Management of IGM cases needs to be tailored according to the clinical presentation. Precise radiologic and pathologic data interpretation by a multidisciplinary breast team will facilitate diagnosis and minimize unnecessary intervention.  相似文献   
996.

Background  

The prevalence of gastroesophageal reflux disease (GERD) and/or hiatal hernia (HH) is significantly increased in morbidly obese patients. Laparoscopic bariatric procedures such as gastric banding (LGB) and Roux-en-Y gastric bypass have been shown to improve both obesity and reflux symptoms. The aim of this paper is to evaluate the effectiveness of laparoscopic sleeve gastrectomy (LSG) and hiatal hernia repair (HHR) for the treatment of obesity complicated by HH.  相似文献   
997.
Spontaneous Regression of a Metastatic Liver Tumor: Report of a Case   总被引:1,自引:0,他引:1  
A 60-year-old man, who suffered from advanced rectal cancer accompanied with liver metastasis, underwent an abdominoperineal resection and a partial hepatectomy. He remained well until 4 months after surgery when he developed a biopsy-proven recurrent intrapelvic mass and multiple liver tumors. At 6 months after surgery, the metastatic liver tumors grew larger and almost completely occupied both lobes of the liver. However, 9 months after surgery, the liver tumors regressed remarkably and his clinical condition improved without any specific treatment for cancer. Although he died of cancerous peritonitis 18 months after surgery, the autopsy findings did not indicate any apparent regrowth of the liver tumors. To date, only one case report of a spontaneous regression of a metastatic liver tumor from colorectal cancer has been published in the English literature. We herein describe this rare case and discuss some of the reasons potentially responsible for the regression. Received: July 16, 2001 / Accepted: March 5, 2002  相似文献   
998.
Postinjury abdominal compartment syndrome (ACS) has evolved during the 1980s together with the introduction of damage control surgery (DCS) principles. DCS made it possible to salvage severely injured trauma patients who previously would have exsanguinated due to uncontrollable coagulopathic bleeding. These patients had severe hemorrhagic shock; their abdomens were tightly packed and had ongoing massive resuscitation. ACS is a lethal complication of the damage control patients. For today the pathophysiological characteristics of ACS are described, the intra-abdominal pressure is measured on many intensive care units. Postinjury ACS (primary and secondary) is one of the better characterized etiological types of ACS: risk factors, diagnostic criteria, independent predictors and preventive strategies are all well documented. Since the mortality of full-blown postinjury ACS is still unacceptably high and does not seem to improve with earlier decompression, prevention is the recommended strategy to decrease the morbidity and mortality. Open abdomen is one of the important preventive strategies but it is not free from morbidity and mortality. With aggressive open abdomen management in postinjury ACS these complications can be minimized. More importantly, timely hemorrhage control and hemostatic resuscitation are the likely solutions for more efficient prevention of the postinjury ACS.  相似文献   
999.
Bariatric surgery has been demonstrated to be an effective treatment for morbid obesity. The purpose of this study is to investigate the incidence of pre- and post-operative deep venous thrombosis (DVT) in Lap-Band surgical patients. This study group comprised 56 consecutive patients who underwent Lap-Band surgery. Mean age and body mass index were 38 years (range: 18–64 years) and 50.9 kg/m2 (range: 53–74 kg/m2), respectively. All the patients were screened with duplex ultrasonography pre- and post-operatively. There were no iliac, femoral, or popliteal vein thromboses detected at any given point of time. No patient had any clinical signs or symptoms of DVT post-operatively. There were no observable differences attributable to DVT prophylaxis. This data suggest that in the setting of chemical and mechanical prophylaxis, the incidence of DVT in patients undergoing Lap-Band surgery at an established bariatric centre is minimal.  相似文献   
1000.
Background Benign esophageal pseudoachalasia is a rare condition. Discussion We report the case of a 70-year-old man who complained of severe dysphagia after laparoscopic Nissen fundoplication and crural mesh repair performed for long-standing gastroesophageal reflux disease. Severe dysphagia and nocturnal aspiration developed soon after the operation. A marked dilatation of the esophageal body and a manometric pattern resembling achalasia was documented. Results Endoscopic balloon dilatation was ineffective. Five months after the initial operation, the patient underwent revisional laparoscopic surgery that consisted of Nissen’s wrap takedown, enlargement of the hiatus with partial resection of the mesh, Heller myotomy, and Dor fundoplication. After a 2-year follow-up, the patient is doing well and is free of symptoms.  相似文献   
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