多层螺旋CT及其后处理技术在诊断股骨颈骨折中的临床应用

目的探讨多层螺旋cT及其后处理功能在股骨颈骨折诊断中应用价值。方法对96例髋关节外伤病例采用16层螺旋cT进行多平面重建（MPR）、容积重建（VR）,评价股骨颈有无骨折和对骨折分型。结果96例髋关节外伤中,确诊股骨颈骨折94例,排除股骨颈骨折2例,94例骨折病例中头下型16例,经颈型50例,颈基底部型28例。结论多层螺旋cT及其后处理功能在股骨颈骨折诊断中具有重要临床实用价值。     

Multi-detector dental CT in evaluation of impacted maxillary canine

Purpose

To evaluate the role of multi-detector dental CT in the evaluation of the impacted maxillary canine.

Methods and patients

This prospective study included 20 patients who were clinically suspected of having impacted permanent maxillary canines. They were 10 males and 10 females with mean age of 23.3 years. They were exposed to plain radiographs and referred for further evaluation using multi-detector dental CT scanner. The panoramic and paraxial images were obtained. Then reformatted images were done in different planes. Imaging data were analyzed for localization and complication of impacted maxillary canine. Distances and angles measurements were made. MDCT findings were compared with intra-operative data of 24 impacted canines.

Results

A total of 28 impacted maxillary canines were studied in 20 patients. Twelve patients presented with a unilateral impacted canines and 8 with bilateral impactions. The localization of the root apex was 3 (10.7%) labial, 6 (21.4%) palatal, and 19 (67.9%) mid alveolus. The average of the angulations of the impacted maxillary canines to the mid sagittal plane was 39.64. Root resorption was detected in 16 cases.

Conclusion

MD dental CT provides more reliable and accurate information for the intraosseous location, inclination, and morphology of impacted maxillary canine.     

探讨0.5mm螺旋扫描及重建显示正常颞骨岩部解剖的优势

目的:探讨多排螺旋CT 0.5 mm层厚横断及冠状重建图像显示正常颞骨解剖结构的优势。方法:对15例检查者行sequence1.0 mm层厚直接横断及冠状扫描,并行0.5 mm层厚横断螺旋扫描、0.5 mm层厚横断和冠状重建。由两位神经影像诊断医师按盲法原则分别对两种图像进行独立评分。结果:27侧成人正常颞骨纳入研究。对观察者1和2进行Wicoxon符号配对秩和检验,分别得出T+=378,和T+=363,差异均有统计学意义(P<0.05)。两观察者观察结果的Spearman秩相关分析,相关系数rs=0.10928,P<0.005,两观察者的评分结果具有相关一致性。结论:多排螺旋CT 0.5 mm层厚横断及冠状重建像达到各向同性,在显示颞骨解剖结构方面,较1.0 mm层厚直接横断和冠状扫描图像更有利于显示颞骨精细解剖结构,其便捷的MPR图实现了颞骨复杂且细微的解剖结构的显示要求,为颞骨解剖结构研究提供了新方法。     

多层螺旋CT及多平面重建技术在主动脉夹层动脉瘤中的应用

目的 :探讨多层螺旋 CT及多平面重建技术在主动脉夹层动脉瘤的诊断和治疗中的应用价值。方法 :对2 8例主动脉夹层动脉瘤病人进行多层螺旋 CT平扫加强化并利用原始数据在 AW4 .2工作站进行 MPR重建。结果 :所有病例均直观的显示动脉内膜剥脱的范围及其与各分支血管的关系 ,真假腔形态及大小 ,93%显示破口位置。结论 :螺旋 CT及其多平面重建技术能准确反映夹层动脉瘤分型 ,对临床医生的治疗方法提供重要的参考。     

64层螺旋CT扫描多平面重建在副鼻窦检查中的价值

目的:探讨64层容积CT扫描多平面重建在副鼻窦检查中的价值。方法:86例患者行鼻副窦64层CT容积扫描,经行冠状位、矢状位、轴位的多平面重建,观察鼻副窦结构及病变范围的显示情况。结果:64层容积CT扫描冠状位、矢状位重建后62例上颌窦黏膜增厚、48例筛窦黏膜增厚、17例蝶窦黏膜增厚、7例额窦黏膜增厚。所有病例均显示钩突、筛窦漏、半月裂、筛泡及中鼻甲等的结构,鼻中隔偏曲39例,中鼻甲反向弯曲28例、中鼻甲气化11例,钩突肥大16例,钩突明显偏移9例,钩突气化5例,筛泡过度气化15例,Haller气房6例。结论:64层螺旋CT扫描多平面重建技术克服了常规CT扫描的缺点,并可以清晰方便显示副鼻窦腔内解剖结构及解剖变异,为鼻副窦炎及其原因的临床诊断提供可靠的影像资料。     

多排螺旋CT对隐匿性肋骨骨折的诊断价值

目的评价多排螺旋CT对隐匿性肋骨骨折的诊断价值。方法对21例有明确胸部外伤史，临床症状明显，但X线平片检查阴性，或多发肋骨骨折者需要明确记数的行多排螺旋CT扫描，并经AW4．3工作站后处理后，分析其表现。结果21例有隐匿性肋骨中，第1肋5例，第2肋4例，腋段骨折7例，后肋近胸椎处2例，前肋近胸骨处2例，膈下1例。结论多排螺旋CT是诊断隐匿性肋骨骨折的理想的影像手段，结合VR、MPR及轴位薄层图象，为临床提供有价值的诊断和解剖信息。     

平片与CT检查技术在鼻部外伤的应用和对比

目的 通过普通平片与CT检查技术在鼻部外伤中的应用和对比，进一步加深理解16层螺旋CT检查的技术价值和临床重要性。方法38例鼻部外伤患者通过普通平片与16层螺旋CT作比较。结果38例中CT检出鼻骨单侧骨折31例，双侧骨折6例；同时合并上颌骨额突骨折6例；鼻骨间缝分离4例，合并鼻中隔骨折13例；伴副鼻窦积液、骨壁骨折5例，及腭骨鼻前嵴骨折3例。而平片未显示者为7例，平片可疑骨折8例，最后确诊7例并排除2例，平片未发现，而CT检出并发症19例。16层螺旋CT比较平片差异有非常显著性意义（X^2=40．82，P〈0．005）。结论鼻骨结构细小，单一的平片检查存在许多不确定因素，16层螺旋检查极大地提高了检出率，减少了误诊和漏诊，同时有利于对并发症的观察，因此对临床的治疗和法律上纠纷具有重要的指导意义。     

Correlation between MRI and biopsies under second look ultrasound

The term “second look” lesions in MRI refers to lesions detected by MRI that were not initially seen on mammography or ultrasound. The objectives of our study were to analyse the displacement of targets between MRI and ultrasound; to define discriminating BIRADS morphological criteria to predict benign or malignant character and better establish the indications of second look ultrasound and biopsy; and to analyse the agreement between ultrasound and MRI in terms of morphological criteria. A retrospective and monocentric review was performed of the records of consecutive patients with breast abnormalities (mass or non-mass) initially detected by MRI that were not initially seen on mammography or ultrasound. All patients with abnormalities found during the performance of second look ultrasound and biopsied were included in the study. All lesions were documented using the BIRADS lexicon for MRI and ultrasound. Of 100 included patients, 108 lesions were detected by MRI, found via second look ultrasound and biopsied between January 2008 and 2010. All of the included patients were followed-up for a variable period, from 2 to 5 years. Eighty-two upon 108 biopsied lesions (76%) were benign and 26/108 lesions (24%) were malignant. This study confirmed the switch from procubitus to decubitus essentially displaces the tumour in the antero-posterior direction. It showed that the risk factors were not reliable criteria for establishing an indication for second look ultrasound. This study also showed that circumscribed contours and a progressive enhancement curve (type I) for masses on MRI had the strongest negative predictive value of greater than 0.85. In ultrasound, the round or oval shape, circumscribed contours and the parallel orientation to the skin favoured benignity with a NPV of greater than 0.85. For masses, the study showed that the agreement in interpretation of the benign versus suspicious morphological criteria between the MRI and the ultrasound was very weak for the shape (Kappa = 0.09) and weak for the contours (Kappa = 0.23). Finally, the MRI overestimated the size of the targets compared to ultrasound (Student t-test, p = 0.0001). The performance of second look ultrasound has to be performed after the detection of an abdnormality on MRI even for lesion classified BIRADS 3. The biopsy indications must be wide with insertion of a clip and a control MRI. Only this control allows to stop the investigation if the biopsied lesion is benign.     

Cone-Beam CT Hepatic Arteriography in Chemoembolization for Hepatocellular Carcinoma: Angiographic Image Quality and Its Determining Factors

PurposeTo analyze image quality and the factors that determine it for cone-beam computed tomography (CT) hepatic arteriography in chemoembolization for hepatocellular carcinoma (HCC).Materials and MethodsFrom September 2009–December 2010, 399 consecutive patients referred for chemoembolization of HCC were scheduled for cone-beam CT scan. There were 12 patients (3%) excluded because of difficulty with breath-hold. Of the 387 patients who underwent cone-beam CT hepatic arteriography, 100 patients were ultimately included in the study according to inclusion criteria. Maximum intensity projection images were scored for image quality of each segmental hepatic artery. Potential determining factors for image quality were diaphragmatic motion, portal vein enhancement, and hepatic artery-to-parenchyma enhancement ratio. The flow rate of contrast media, x-ray delay, and location of the catheter tip were also evaluated.ResultsIt was possible to trace at least subsegmental hepatic arteries in 625 of 700 segments (89.3%) on cone-beam CT hepatic arteriography. Diaphragmatic motion, prominent portal vein enhancement, and low hepatic artery-to-parenchyma enhancement ratio worsened image quality (P < .001, P = .022, and P = .017). Owing to cardiac motion artifacts, image quality of the left lateral segments (S2 and S3) was poorer compared with the remaining hepatic segments (S4–S8).ConclusionsIn most cases, the quality of cone-beam CT hepatic arteriography images was good enough to trace subsegmental hepatic arteries at a minimum. Respiratory and cardiac motion, portal vein enhancement, and hepatic artery-to-parenchyma enhancement ratio significantly affected the image quality of cone-beam CT hepatic arteriography.     

Radiological evaluation of post-traumatic tracheal stenosis using multidetector CT with multiplanar reformatted imaging and virtual bronchoscopy: Comparison with intraoperative findings

Aim

To evaluate the diagnostic utility of multidetector computed tomography (MDCT) (axial, multiplanar reformatted images and virtual bronchoscopy) in preoperative assessment of post-traumatic tracheal stenosis.

Materials and methods

Twenty-four patients with post-traumatic tracheal stenosis underwent tracheal resection anastomosis. The diagnosis was ascertained on the basis of history and rigid-bronchoscopy. All patients were preoperatively evaluated by MDCT. Intraoperative findings were used as the gold standard. Lesions were evaluated in terms of site, distance from the vocal cords, length, grade of the stenosis and length of the planned resected segment.

Results

The sensitivity of MDCT was 100%, 100%, 92.3%, 92.3%, 96% and its accuracy was, 100%, 100%, 96%, 96%, 88.8% in assessment of tracheal stenotic site, distance from the vocal cords, length, length of segment planned for resection and stenotic grade, respectively. MPR (coronal and sagittal reformatted) images were 100% sensitive in detecting stenotic site and distance from the vocal cord. It showed 92.3% sensitivity and 96% accuracy in assessment of the stenotic segment length and the length of segment planned for resection. VB showed 96% sensitivity and 88.8% accuracy.

Conclusion

MDCT with its various display modes improved the preoperative evaluation of post-traumatic tracheal stenosis. The combined interpretation of axial, multiplanar reformatted and VE leads to improved diagnostic confidence. We recommend it as a constant demand for preoperative evaluation of post-traumatic tracheal stenosis.