股骨头缺血性坏死X线与核素骨显像诊断的分析

本文报告了３１例（４５个髋）股骨头缺血性坏死的诊断和研究结果。Ｘ线检查阳性率为８０％，核素骨显像阳性率为９７．８％，结果表明对早期病灶，骨显像较ｘ线平片敏感，文内比较分析了ｘ线平片与骨显像在诊断中的价值。对ｘ线平片阴性而可疑有股骨头坏死的患者应做骨显像检查，以免误漏诊。     

SPECT／CT显像诊断转移性骨肿瘤的临床意义

目的探讨SPECT／CT显像在肿瘤骨转移诊断中的临床价值。方法选择237例可疑肿瘤骨转移和不明原因骨痛的患者,注射99Tcm亚甲基二膦酸盐（MDP）后180min行全身骨显像,对发现的可疑病灶立即行同机CT扫描,再行图像融合和分析。对患者资料进行回顾性分析,平面显像和SPECT／CT显像结果与病理结果对照21例,与2种以上影像技术（MRI、CT、X线）诊断结果对照106例,与随访2年结果对照110例,计算平面显像和SPECT／CT与这些对照方法的诊断符合率。采用SAS6．12软件进行统计学处理,对平面和SPECT／CT显像的诊断符合率行／检验。结果平面显像237例中142例诊断和对照方法诊断结果符合,其中72例良性病变,70例骨转移,肯定性诊断总符合率95．30％（142／149）。SPECT／CT显像237例中224例结果和对照方法诊断结果符合,其中104例为良性病变,120例为骨转移,SPECT／CT诊断总符合率94．51％（224／237）,其中肯定性诊断总符合率为99．48％（192／193）。平面显像和SPECT／CT对骨转移的肯定性诊断符合率差异有统计学意义（x2=5．37,P=0．024）。结论SPECT／CT显像不仅可以精确定位,而且还可补充单独CT检查获得的诊断信息,明显提高对骨病变诊断的价值。     

严重急性呼吸综合征康复患者骨缺血性坏死患病率的MRI筛查研究

目的采用MRI对康复的严重急性呼吸综合征（SARS）患者骨缺血性坏死进行筛查，探讨康复SARS患者骨缺血性坏死的患病率，及与激素使用的关系。方法用MRI对448例感染SARS的康复患者进行骨缺血性坏死筛查。所有受试者都做了双髋和双膝关节MR扫描，其中192例还扫描了肩和踝关节。采用体线圈同时扫描双侧关节，扫描序列常规做冠状面T1WI，如发现有骨缺血性坏死征象，加扫短时反转恢复（STIR）序列。178例在MR检查的同一天还行双髋关节正位和蛙式位数字X线摄影（DR）片。所有MR图像由3位高年资医生阅片，诊断有无骨缺血性坏死。由2位医生在不知道MRI结果的情况下阅读双髋关节正位和蛙式位DR片，判断有无骨缺血性坏死。448例中在“SARS临床研究数据库”有用药记载者386例，其中361人在治疗过程中使用激素并记载了剂量和时间；“SARS临床研究数据库”无用药记载的其余62例中有59例自述治疗时使用激素。结果骨缺血性坏死的MRI表现为关节面下骨髓内出现弧形或线形异常信号带，T1WI为低信号，在STIR序列上为高信号，与临床上所见的因其他疾病而使用激素或饮酒等原因引起的骨缺血性坏死表现相同。MRI筛查发现在448例中共有138例（30．8％）出现1处以上骨缺血性坏死。28例未用激素的患者中有1例出现有股骨干骨梗死征象（1／28），420例使用激素患者的MRI筛查发现137例（32．6％）出现至少1处骨缺血性坏死MRI表现，两组间差异有统计学意义（P〈0．05）。股骨头缺血性坏死101例，均有使用激素史，占激素使用者的24．0％（101／420）。膝关节骨缺血性坏死84例，占激素使用者的20．0％（84／420）。同时累及股骨头和膝关节者48例，占激素使用者的11．4％（48／420），仅发生在股骨头者53例，占激素使用者的12．6％（53／420），而仅发生于膝关节者36例，占激素使用者的8．6％（36／420）。192例双侧肩关节和踝关节MR扫描发现肱骨头缺血性坏死26例（13．5％），踝关节骨缺血性坏死13例（6．8％）。178例DR和MRI诊断股骨头坏死的阳性符合率为14．1％，DR诊断的敏感度为11．0％，特异度为97．0％。秩和检验显示骨缺血性坏死组的激素总剂量，甲泼尼龙（甲强龙）的使用时间、平均日剂量和总剂量均大于无坏死组（P〈0．05）。多因素Logistic回归分析表明甲泼尼龙日平均剂量和平均使用时间是发生骨坏死的危险因素（P〈0．05）。结论MRI筛查发现北京地区使用激素治疗的SARS患者的骨缺血性坏死患病率较高，主要发生在股骨头、膝、肩和踝关节，常累及多个部位，多数为双侧同时受累。是否使用激素、激素使用剂量和时间是发生骨坏死的危险因素。     

18F-FDG PET显像用于鼻咽癌诊断及分期

目的 探讨^18F-脱氧葡萄糖（FDG）PET显像在鼻咽癌诊断中的价值。方法 回顾性分析33例鼻咽癌患者的^18F-FDG PET显像效果。其中初诊患者4例，治疗后29例。行常规头颈部或全身^18F-FDG PET显像。结果 ①33例患者中，鼻咽部有恶性病灶（原发或复发病灶）者16例，PET灵敏度为100％，假阳性2例，特异性为88．3％，准确性为93．9％。与PET显像前的21例CT或MRI结果相比较，PET3检出鼻咽部恶性病灶10例，较CT或MRI多检出2例。②33例中22例有转移灶，PET检出20例（90．9％），较PET显像前的其他检查多检出5例；PET显像和PET显像前的其他检查皆有3例假阳性。在检出转移病灶数方面，PET显像多发现1处或多处转移灶有13例，PET显像少发现转移灶的2例。结论 ^18F-FDG PET显像灵敏、准确、全面，在鼻咽癌的诊断、早期复发灶及全身转移灶检出方面有重要价值。     

重型SARS患者的转归及胸部影像学随访观察研究

目的 探讨重型SARS患者的转归并随访观察其恢复期胸部影像学表现。方法 回顾性分析54例重型SARS患者的转归，随访观察25例重型SARS患者恢复期的胸片、CT扫描表现。结果 54例重型SARS患者，死亡15例(其中1例尸检)，临床治愈39例。随访观察的25例中21例随访时间为发病后158—238d，CT扫描发现8例有肺间质增生(38．10％)；4例有纤维性病灶(19．05％)；12例有磨玻璃样密度病变残留(57．14％)；7例双肺未见异常改变(33．33％)。结论 肺间质增生、纤维性病灶、磨玻璃样密度病变残留是重型SARS患者恢复期的主要胸部表现，其发生率高于普通型SARS患者。     

骨显像和血HLA—B27检测早期诊断强直性脊椎炎

目的 探讨放射性核素骨显像及人类白细胞抗原（HLA－B27）检查对强直性脊椎炎（AS早期诊断价值。方法 对首次发病且X线检查未见异常的35例后臀部疼痛患者作了骨显像及HLA－B27测定，并制订了对AS的早期诊断标准，对患者临床随访0．5－2．5a，用纽约会议标准再次进行诊断，以评价早期诊断标准的准确性。结果 根据早期诊断标准有30例患者被诊断为AS，随访后再次诊断，其中29例被诊断为AS，前后2次诊断符合率为96．7％。结论 放射性核素骨显像与HLA－B27检查相结合对AS的早期诊断和治疗可提供可靠依据。     

纤维性骨皮质缺损的X线、CT和MRI诊断

目的：探讨纤维性骨皮质缺损的X线、CT和MRI诊断价值。方法：15例全部摄平片，10例行CT检查，5例行MRI扫描；随访1－8年，2例手术病理证实。分析缺损的X线、CT、MRI特点。结果：15例累及18骨，共20个病灶。病灶80％（16／20）位于股骨下干骺端，呈凹向骨髓腔的杯口样或碟形缺损，表面无骨壳，内缘有硬化线，部分缺损内有纵形骨性分隔。4个病灶随访复查消失。结论：X线、CT和MRI能对纤维性骨皮质缺损提供较准确诊断，随访观察可了解缺损的转归。     

SPECT/CT融合显像对乳腺癌骨转移的诊断价值

目的 评价SPECT/CT融合显像对^99Tc^m-MDP全身骨显像难于确诊的乳腺癌骨病灶的鉴别诊断价值.方法 对^99Tc^m-MDP全身骨显像难于确诊的132例乳腺癌患者的210个病灶行局部SPECT/CT同机融合断层显像,以临床随访及病理检查获得最终诊断结果,计算SPECT/CT融合显像对骨转移灶的诊断准确率、灵敏度、特异度、阳性预测值及阴性预测值,并对比不同部位病灶的诊断准确率差异.结果 ①210个病灶经SPECT/CT融合断层显像正确诊断的恶性病灶82个（39.0％）,良性病灶112个（53.3％）,诊断准确率为92.4％（194/210）,灵敏度为94.3％,特异度为91.1％,阳性预测值为88.2％,阴性预测值为95.7％.②SPECT/CT同机融合断层显像对不同部位的病灶的诊断准确率不一致,脊椎的诊断准确率最高,为95.9％（94/97）,肋骨最低,为83.7％（36/43）,其差异有统计学意义（χ^2=7.81,P＜0.05）.结论 SPECT/CT同机融合显像能够对^99Tc^m-MDP全身骨显像难于确诊的病灶进行准确诊断,其对不同部位的病灶的诊断准确率有差异,脊椎的诊断准确率最高,肋骨最低.     

膝关节骨挫伤的MRI诊断及其随访研究

目的:探讨膝关节骨挫伤的MRI表现及其随访特征.方法:回顾性分析112例膝关节外伤后普通X线检查膝关节未发现明显异常而MRI检查发现骨挫伤的患者,所有病例均行膝关节T1WI、T2WI、STIR序列扫描,着重分析骨挫折的MRI表现.结果:112例膝关节骨挫伤发现病灶235个,在MRI表现为不规则的斑片状、地图状的异常信号区域,病灶在T1WI上表现为不均匀低信号,在T2WI上表现为混杂高信号,在STIR序列上表现为明显高信号区,其中99例伴有不同程度的膝关节其他损伤.235个骨挫伤病灶中,在T1WI上显示209个,在T2WI上显示病灶203个,在STIR上全部显示,而且病灶边界和范围较T1WI、T2WI显示更清楚.15例进行了MR随访复查,2例膝关节骨挫伤在24周尚未完全吸收.结论:MRI是早期诊断和定期随访膝关节骨挫伤的重要影像学方法.     

SPECT和CT融合骨显像在小儿神经母细胞瘤中的应用

目的探讨SPECT和CT融合骨显像在探测小儿神经母细胞瘤（NB）转移性骨肿瘤中的临床价值。方法回顾性分析24例NB患儿,均行全身平面骨显像及局部SPECT和CT融合骨显像。将骨病灶显示的清晰度分为5级（不可见、模糊、可见、清晰、非常清晰）,良恶性诊断的确定性分为3级（不确定、可以确定、十分确定）,诊断效能指标包括灵敏度、特异性及准确性。对显像图像在骨病灶的清晰度显示、良恶性确定性诊断及探测恶性骨病灶的诊断效能方面进行分析,采用秩和检验及χ^2检验进行比较。结果24例NB患儿,全身平面骨显像发现骨病灶72个,有5个骨病灶未能显示,SPECT和CT融合显像和单独SPECT显像均分别发现骨病灶77个。对骨病灶的清晰度显示SPECT和CT融合显像,单独SPECT显像均优于平面显像（日值均为69．000,P均〈0．05）。平面显像和SPECT显像诊断恶性骨病灶的准确性分别为45．45％（35／77）和62．34％（48／77;χ^2=4．416,P〈0．05）,SPECT和CT融合诊断恶性骨病灶的灵敏度、特异性和准确性均较平面显像有提高,分别为82．35％（42／51）和53．19％（25／47）、88．46％（23／26）和40．00％（10／25）、84．42％（65／77）和45．45％（35／77）,χ^2=12．571,14．016和25．667,P均〈0．01。与SPECT显像的特异性（14／26,53．85％）和准确性（48／77,62．34％）相比,SPECT和cT融合诊断恶性骨病灶的特异性和准确性提高（χ^2=7．589,9．606,P均〈0．01）,两者间灵敏度差异无统计学意义（χ^2=2．942,P〉0．05）。SPECT和CT融合显像骨病灶良恶性的确定性诊断优于SPECT（H=28．000,P〈0．05）和平面显像（H=21．000,P〈0．05）。结论SPECT和CT融合骨显像能探测到NB患儿更多的骨病灶,是一种较好的探测NB患儿转移性骨肿瘤的显像方法。     

Controversies in cervical spine imaging in trauma patients

No area of emergency radiology has generated as much discussion in recent years as the subject of cervical spine imaging for trauma patients. This review will be in three parts. The first will examine the indications for cervical imaging and will focus on those factors that make patients at high risk or low risk for cervical injury. The second part will discuss the merits of radiography and computed tomography as the main screening diagnostic examination. In addition to the roles of each modality in the evaluation process, such factors as efficacy of diagnosis, time (duration) of study, and cost will be discussed. Finally, the third part will explore the methods currently employed to clear the cervical spine in comatose patients.Presented at the Annual Meeting of the American Society of Emergency Radiology, Las Vegas, Nevada, 22–25 October, 2003     

Influence of in vivo copper on MR images of the liver in rats

To investigate the effects of in vivo copper on magnetic resonance (MR) images, the authors studied Long-Evans cinnamon rats, which develop hepatitis and hepatocellular carcinoma as a result of abnormal copper metabolism. The livers of the rats were imaged before hepatitis developed; the absence of hepatic disease was confirmed histopathologically. The copper that accumulated in the liver of the rats was thought to exist in the form of divalent ions, which were suspected of reducing the T1 and T2 of neighboring protons. However, the signal intensities of the liver on T1- and T2*-weighted images did not change, suggesting that in vivo copper, even when accumulated abnormally, does not influence the signal intensity of MR images.     

MR imaging of muscle and tender points in fibromyalgia

Fibromyalgia is a syndrome manifested by chronic, diffuse muscu-loskeletal aching and soreness, palpable muscle tender points, and other symptoms. Standardized clinical diagnostic criteria have recently been developed. Skeletal muscle has been postulated as the end organ in this disease. Biochemical, histologic, electromyographic, and conventional radiographic studies have demonstrated no definitive abnormality. This study sought to establish whether magnetic resonance (MR) imaging could demonstrate any abnormality in these patients. Eighteen patients were entered in the study, 14 of whom were able to complete their examinations. T1 -weighted, T2-weighted, gradient-echo, and STIR (short-tau inversion-recovery) sequences were performed in all patients, with selected patients examined with T1weighted, gadopentetate dimeglu-mine-enhanced sequences. The trapezius and suboccipital regions were imaged in patients who, clinically, had active fibro-myalgia. No abnormalities could be detected. The authors conclude that the conventional MR imaging used in this study was unable to depict any primary skeletal muscle abnormality in fibromyalgia.     

Brodie Abscess: MR imaging appearance in 10 patients

The magnetic resonance (MR) imaging features of Brodie abscess have not yet been fully evaluated. Ten patients with Brodie abscess, eight of long bone and two of vertebra, were studied with MR imaging. Long bone abscess had a characteristic “target” appearance with four layers: (a) a center with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR (short-inversion-time inversion recovery) images, (b) an inner ring isointense to muscle on T1-weighted images and with high signal intensity on T2-weighted and STIR images, (c) an outer ring hypoin-tense on all images, and (d) a peripheral halo hypointense on T1-weighted images. In six of eight cases, a soft-tissue mass was found. The two vertebral abscesses had a less specific appearance, with low signal intensity on T1-weighted images and high signal intensity on T2-weighted and STIR images. Only the peripheral halo was clearly identified in both cases.     

Localized proton MR spectroscopy of the brain in children

Small-voxel (3.0–8.0 cm³), magnetic resonance (MR) imaging–guided proton MR spectroscopy was performed in 54 patients (aged 6 days to 19 years) with intracranial masses (n = 16), neurodegenerative disorders (n = 34), and other neurologic diseases (n = 4) and in 23 age-matched control subjects without brain disease. A combined short TE (18 msec) stimulatedecho acquisition mode (STEAM) and long TE (135 and/or 270 msec) spin-echo point-resolved spatially localized spectroscopy (PRESS) protocol, using designed radio-frequency pulses, was performed at 1.5 T. STEAM spectra revealed short T2 and/or strongly coupled metabolites; prominent resonances were obtained from N-acetyl aspartate (NAA), choline-containing compounds (Cho), and total creatine (tCr). Lactate was well resolved with the long TE PRESS sequence. Intracranial tumors were readily differentiated from cerebrospinal fluid (CSF) collections. All tumors showed low NAA, high Cho, and reduced tCr levels. Neurodegenerative disorders showed low or absent NAA levels and enhanced mobile lipid, glutamate and glutamine, and inositol levels, consistent with neuronal loss, gliosis, demyelination, and amino acid neuro-toxicity. Preliminary experience indicates that proton MR spectroscopy can contribute in the evaluation of central nervous system abnormalities of infants and children.     

Interventional procedures in the upper urinary tract

The introduction and acceptance of percutaneous nephrostomy as a safe and effective alternative to surgical nephrostomy served as the impetus for the development and expansion of an ever-increasing number of techniques that are encompassed by the term “interventional uroradiology.” This article reviews many of the non-vascular interventional techniques that have proliferated during the past decade and that are currently used in the kidney, ureter, and perinephric space. The authors emphasize those procedures that are most frequently employed, as well as their own preferences and perspectives on these procedures.     

Imaging in spinal trauma

Because it may cause paralysis, injury to the spine is one of the most feared traumas, and spinal cord injury is a major cause of disability. In the USA approximately 10,000 traumatic cervical spine fractures and 4000 traumatic thoracolumbar fractures are diagnosed each year. Although the number of individuals sustaining paralysis is far less than those with moderate or severe brain injury, the socioeconomic costs are significant. Since most of the spinal trauma patients survive their injuries, almost one out of 1000 inhabitants in the USA are currently being cared for partial or complete paralysis. Little controversy exists regarding the need for accurate and emergent imaging assessment of the traumatized spine in order to evaluate spinal stability and integrity of neural elements. Because clinicians fear missing occult spine injuries, they obtain radiographs for nearly all patients who present with blunt trauma. We are influenced on one side by fear of litigation and the possible devastating medical, psychologic and financial consequences of cervical spine injury, and on the other side by pressure to reduce health care costs. A set of clinical and/or anamnestic criteria, however, can be very useful in identifying patients who have an extremely low probability of injury and who consequently have no need for imaging studies. Multidetector (or multislice) computed tomography (MDCT) is the preferred primary imaging modality in blunt spinal trauma patients who do need imaging. Not only is CT more accurate in diagnosing spinal injury, it also reduces imaging time and patient manipulation. Evidence-based research has established that MDCT improves patient outcome and saves money in comparison to plain film. This review discusses the use, advantages and disadvantages of the different imaging techniques used in spinal trauma patients and the criteria used in selecting patients who do not need imaging. Finally an overview of different types of spinal injuries is given.     

MR imaging of blood oxygenation-dependent changes in focal renal ischemia and transplanted liver tumor in rat

The potential of using fast magnetic resonance (MR) imaging in conjunction with apnea-induced blood deoxygenation for the noninvasive monitoring of relative perfusion in the rat abdomen has been studied with two experimental models: glycer-ol-induced focal renal ischemia and transplanted liver tumor. Gradient-echo echo-planar imaging (GRE-EPI) (TE of 20 msec at 2 T) of liver and kidney was performed before, during, and after a 60-second apnea episode and then was followed in the same rat by contrast-enhanced (a) GRE-EPI and (b) T1-weighted spin-echo imaging (TR msec/TE msec = 200/6) with polylysine-(gadolmium-DTPA [diethylenetriaminepentaacetic acid]). The results indicate that a noninvasive vascular challenge due to apnea can be used for the detection of focal tissue perfusion abnormalities in rat kidney and liver tumor.