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81.
Objectives To analyze the relationship between lateral displacement of the mandible and scoliosis.
Methods From April 2002 through July 2003, we examined posteroanterior cephalometric radiographs and chest X-rays from 85 patients
with jaw deformities and a control group of 20 patients with no jaw deformities. To measure the lateral shift of the mandible,
we drew a horizontal baseline (X axis) on the cephalogram connecting the intersection of the external margins of the orbits and the most lateral points of
the greater wings of the sphenoid. A vertical baseline (Y axis) was then marked perpendicular to the X axis, intersecting the ethmoid crista galli. Then, we measured the lateral displacement of the mandibular mentum from the
Y axis. Displacement to the right was designated positive; that to the left was designated negative. Cobb's method was used
to measure scoliosis curves on chest X-rays; the direction of the curve was designated similarly.
Results Of the 85 patients with jaw deformity, 23 (27.1%) had a Cobb angle exceeding 10°. None of the control group had scoliosis
exceeding 10°. No correlation was found between the direction of mandibular displacement and the direction of scoliosis.
Conclusion This study suggests a relationship between jaw deformities and scoliosis, as scoliosis was found in 27.1% of the patients
with a main complaint of jaw deformity. 相似文献
82.
PT Foley A Ganeshan S Anthony R Uberoi 《Journal of Medical Imaging and Radiation Oncology》2010,54(1):9-16
This is a retrospective review of the results at our institution of using multi-detector CT angiography (CTA) to localise lower gastrointestinal (GI) bleeding. We hypothesised that in our patient population: (i) CTA was unlikely to demonstrate bleeding in patients who were haemodynamically stable; (ii) in haemodynamically unstable patients in whom CTA was undertaken, the results could be used to select patients who would benefit from catheter angiography; and (iii) in haemodynamically unstable patients in whom CTA was undertaken, a subgroup of patients could be identified who would benefit from primary surgical treatment, avoiding invasive angiography completely. A retrospective review was conducted of the clinical records of all patients undergoing CTA for lower GI haemorrhage at our institution between 1 January 2005 and 30 June 2007. Out of the 20 patients examined, 10 had positive CTAs demonstrating the bleeding site. Nine were haemodynamically unstable at the time of the study. Four patients with positive CT angiograms were able to be treated directly with surgery and avoided invasive angiography. Ten patients had negative CTAs. Four of these were haemodynamically unstable, six haemodynamically stable. Only one required intervention to secure haemostasis, the rest stopped spontaneously. No haemodynamically stable patient who had a negative CTA required intervention. CTA is a useful non-invasive technique for localising the site of lower GI bleeding. In our patient population, in the absence of haemodynamic instability, the diagnostic yield of CTA was low and bleeding was likely to stop spontaneously. In haemodynamically unstable patients, a positive CTA allowed patients to be triaged to surgery or angiography, whereas there was a strong association between a negative CTA and spontaneous cessation of bleeding. 相似文献
83.
老年人硬膜下血肿(SDH)系指60岁以上高龄人的SDH而言。由于近年来各国人口老年化率上升,老年人颅脑损伤的比例也随着增高,老年SDH也相应增多[1]。这类病人的临床表 相似文献
84.
85.
86.
多层螺旋CT对胫骨平台骨折的诊断价值 总被引:3,自引:0,他引:3
目的:评价MSCT在胫骨平台骨折的分类及制定合理的治疗方案方面的价值。方法:对24例常规X线平片或临床诊断为胫骨平台骨折的患者进行MSCT扫描,并对图像进行MPR、SSD和VR重建,对骨折的部位、范围、碎骨片的数量或骨折程度、胫骨平台受累情况、手术入路、骨质疏松程度及骨组织的缺损等做出评价。骨折的分型根据Swiss AO-ASIF法。结果:24例患者中有19例进行了手术治疗,术中所见与轴位MSCT和MPR、SSD及VR重建图像综合做出的诊断一致。结论:MSCT及其MPR、SSD、VR重建技术对于胫骨平台的骨折分型及术前评价有重要意义。 相似文献
87.
多层螺旋CT(MSCT)使扫描速度,薄层,覆盖范围达到了很好的统一,是胰腺癌最佳的单项检查手段。本文介绍了MSCT运用于胰腺的技术优势以及具体检查方法,重点叙述其在胰腺癌的诊断,术前可切除性的评估等方面的应用。 相似文献
88.
我院自 1994年使用CT检查以来 ,需增强检查者的比例越来越高。增强检查确实提供了CT平扫不可替代的诊断信息 ,但是碘对比剂的副作用却令人担忧 ,因此 ,CT室的护理人员应认真做好对患者的筛选、敏试工作 ,严格掌握禁忌证 ,加强对副反应的预防性措施及意外抢救工作 ,合理使用对比剂 ,现将我院应用碘对比剂的方法介绍如下。1 严格掌握禁忌证严重的甲状腺功能亢进、失代偿性心肌功能不全者禁忌。妊娠及急性盆腔炎症时禁行子宫输卵管造影。2 认真筛选高危因素有碘造影剂过敏、严重肝肾功能损害、心脏和循环功能不全、肺气肿、体质极差者 ,重… 相似文献
89.
Peter B. Richman MD Shari Dominguez MD David Kasper MD Frederick Chen MD Jeremy Friese MD Joseph Wood MD JD Joseph Collins MD Jeffrey A. Kline MD 《Academic emergency medicine》2006,13(3):295-301
Objectives: To determine interobserver agreement between radiologists for computed tomography (CT) angiography and venography. CT venography of the lower extremities combined with standard CT angiography of the chest may result in an increased overall diagnosis rate of venous thromboembolism (pulmonary embolism or deep venous thrombosis).
Methods: The study had a retrospective cohort design. The population consisted of emergency department patients who were evaluated for suspected pulmonary embolism. A random sample of 50 patients diagnosed and treated for venous thromboembolism and 50 age- and gender-matched patients whose CT angiograms and venograms were read as negative were enrolled. The original reading (R1) was compared with readings of two study radiologists: R2, a general radiologist, and R3, a radiologist with fellowship training in cross-sectional imaging. All readers were blinded to each other.
Results: Both R2 and R3 found both CT angiogram and venogram components technically adequate in 95% (95% CI = 89% to 98%) and 86% (95% CI = 78% to 92%) of studies, respectively. The agreement was very good for CT angiography (lowest agreement = 92%; lowest κ = 0.83) and was good for CT venography (85%, κ = 0.65). In nine cases, R1 read the CT angiogram as negative but the venogram as positive for DVT, whereas both R2 and R3 read both components as negative in four of these nine, suggesting a false-positive isolated DVT rate of 44% (95% CI = 19% to 73%). In no case did R1 read both scan components as negative when R2 and R3 agreed on presence of pulmonary embolism or DVT.
Conclusions: Diagnosis of pulmonary embolism on CT angiography is more reliable than diagnosis of isolated DVT on CT venography. 相似文献
Methods: The study had a retrospective cohort design. The population consisted of emergency department patients who were evaluated for suspected pulmonary embolism. A random sample of 50 patients diagnosed and treated for venous thromboembolism and 50 age- and gender-matched patients whose CT angiograms and venograms were read as negative were enrolled. The original reading (R1) was compared with readings of two study radiologists: R2, a general radiologist, and R3, a radiologist with fellowship training in cross-sectional imaging. All readers were blinded to each other.
Results: Both R2 and R3 found both CT angiogram and venogram components technically adequate in 95% (95% CI = 89% to 98%) and 86% (95% CI = 78% to 92%) of studies, respectively. The agreement was very good for CT angiography (lowest agreement = 92%; lowest κ = 0.83) and was good for CT venography (85%, κ = 0.65). In nine cases, R1 read the CT angiogram as negative but the venogram as positive for DVT, whereas both R2 and R3 read both components as negative in four of these nine, suggesting a false-positive isolated DVT rate of 44% (95% CI = 19% to 73%). In no case did R1 read both scan components as negative when R2 and R3 agreed on presence of pulmonary embolism or DVT.
Conclusions: Diagnosis of pulmonary embolism on CT angiography is more reliable than diagnosis of isolated DVT on CT venography. 相似文献
90.
Ventilation imaging of the lung: Comparison of hyperpolarized helium-3 MR imaging with Xe-133 scintigraphy 总被引:1,自引:0,他引:1
Talissa A. Altes MD Patrice K. Rehm MD Frank Harrell PhD Michael Salerno PhD Thomas M. Daniel MD Eduard E. de Lange MD 《Academic radiology》2004,11(7):729-734
RATIONALE AND OBJECTIVES: To compare hyperpolarized helium-3 (HHe) magnetic resonance imaging (MRI) of the lung with standard Xe-133 lung ventilation scintigraphy. MATERIALS AND METHODS: We performed a retrospective review of 15 subjects who underwent HHe MRI and Xe-133 lung ventilation imaging. Coronal MRI sections were acquired after a single inhalation of HHe gas, and standard posterior planar lung ventilation scintigraphy was performed during continuous breathing of Xe-133 gas. The first breath scintigram of each patient was compared with a composite MR image composed of the sum of the individual MR images and with the individual helium-3 MR images. Ventilation defects on the two imaging modalities were compared for size, conspicuity, and concordance in presence and location. Assessment was done separately for each of four lung quadrants. RESULTS: Comparing the composite HHe MR images with Xe-133 scintigraphy, ventilation defect size, conspicuity and concordance were the same in 67% (40/60), 63% (38/60), and 62% (37/60) quadrants, respectively. Comparing the individual HHe MR image sections with the Xe-133 ventilation scan, there was concordance between the ventilation defects in 27% (16/60) of quadrants. More defects were identified on the individual HHe MR images in 62% (37/60) of quadrants. CONCLUSION: There was good agreement between composite HHe MR image and first breath Xe-133 scintigraphic images, supporting the widely held assumption that HHe MRI likely depicts first breath lung ventilation. 相似文献