CT导引下穿刺活检对胰腺占位性病变的诊断价值

目的 探讨CT导引穿刺活检胰腺占位性病变的诊断价值.方法 回顾性分析CT导引细针穿刺胰腺占位性病变68例,其中胰头区病变49例、胰体12例和胰尾7例.病灶直径2～7 cm,<3cm 10例,3～7 cm 58例.术前均作CT平扫和增强扫描,均采用前路进针,使用20 G细针穿刺.活检标本送病理科作组织病理检查.结果 68例患者均安全地穿刺到病变内,活检成功率为100%.穿刺活检诊断率为恶件病变46例,良性17例,5例未见病变.5例中2例经临床和CT随访均无异常,另3例最终证实胰腺囊腺癌2例和胃癌转移1例.穿刺活检总正确率、灵敏度和特异度分别为96%、95%和100%.CT导引活检对恶性、良性病变的正确率为94%和100%(P>0.05).较大肿块病灶(≥3.0 cm 97%,<3 cm90%)和病变位于胰尾(胰尾100%,胰头96%,胰体92%)的正确率稍高,但经统计学检验正确率差异并无统计学意义(P>0.05),未发现严重的并发症.结论 CT导引经皮细针穿刺活检胰腺占位性病变是一种安全的有效的诊断和鉴别诊断的方法.     

CT导引下的纵隔病变穿刺活检

目的探讨CT导引纵隔病变穿刺活检技术及其临床意义。方法35例纵隔病变在CT导引下行穿刺活检。结果35例纵隔病变穿刺活检病灶成功率100%。诊断准确率94.2%(33/35),其中恶性病变诊断准确率100%(21/21),良性病变为85.7%(11/14)。并发气胸3例(8.6%),纵隔出血1例(2.9%)。结论CT导引下穿刺活检术对于纵隔病变诊断的正确率高,对纵隔病变的诊治具有很大的帮助。     

CT导引下肺内病变穿刺活检:不同大小和不同深度病灶间的比较

目的 探讨病变大小、深度对CT导引下肺内病变穿刺活检诊断正确率、气胸发生率的影响.方法 回顾复习有手术病理、临床或影像学随访的肺内病变CT导引下活检398例,按大小将病灶分为≤2 cm、2～4 cm和≥4 cm 3组.依据病变与胸膜间距离将病灶深度分为≤1 cm、1～3 cm和≥3 cm 3组.比较不同大小、深度病灶CT导引下活检在诊断正确率和并发症发生率方面有无差异.结果 (1)398例CT导引下活检总的诊断正确率为83.2%(331/398),58例(14.6%)发生气胸. (2)3组不同大小病灶活检诊断正确率分别为 73.3%(44/60)、81.5%(176/216)和91.0% (111/122),χ2=9.91, P<0.01;气胸发生率分别为20%(12/60)、16.7%(36/216)和8.2%(10/122),χ2=6.16, P<0.05.(3)3组不同深度病灶活检诊断正确率分别为83.0%(117/141)、85.9%(122/142)和80.0%(92/115),χ2=1.59, P>0.05;气胸发生率分别为2.8%(4/141)、14.8%(21/142)和28.7%(33/115), χ2=34.03, P<0.01.结论 CT导引下肺内病变穿刺活检对小病灶诊断正确率明显低于大病灶,气胸发生率高于大病灶;不同深度病灶CT活检诊断正确率相近,随病灶深度增加气胸发生率增加.     

CT导向下切割活检在纵隔病变诊断中的应用价值

目的 探讨经皮针刺切割活检纵隔病变的临床应用价值.方法 回顾性分析52例纵隔肿瘤CT导向下经皮针刺切割活检术.穿刺针为美国MD公司TRU-CORE 18 G切割针,52例均做切割病理组织学检查,6例加做免疫组化.结果 (1)病变部位前纵隔49例,中纵隔1例,后纵隔2例;(2)43例病理诊断明确,9例病理诊断不确定.穿刺活检正确率为82.7% ,假阴性率为17.3% ,假阳性病例1例;(3)淋巴瘤活检准确性为50%, 辅以免疫组织化学后切割活检的准确性为80%,明显提高了穿刺活检的诊断准确率(χ2 = 3. 96 ,P<0.05);(4) 8 例小病灶穿刺敏感性为50%,44 例大病灶穿刺敏感性为84.1%,穿刺阳性率与病灶大小无关(确切概率法P>0. 05);(5)胸腺类肿瘤、淋巴结转移性癌活检准确性分别为93%、100% ,淋巴瘤活检准确性仅为50%, 胸腺类肿瘤、淋巴结转移性癌活检阳性率显著高于淋巴瘤(P < 0.05)与前2组比较有统计学意义(P < 0.05);(6) 穿刺并发症发生率为9.6%.气胸发生率为5.8%.结论 CT导向下经皮切割活检术是纵隔病变安全而有价值的诊断方法,辅以免疫组织化学技术可以很大提高纵隔病变的诊断正确率.     

CT导引下肺内病变穿刺活检诊断正确率相关因素分析

目的探讨影响CT导引下肺内病变穿刺活检诊断正确率的因素。方法回顾复习有手术病理、临床随访的肺内病变CT导引下穿刺活检435例。应用单因素统计分析和多元逐步Logistic回归分析方法,分析病灶相关因素(病灶良恶性、大小、位置、病灶深度及有无空腔)、操作相关因素(有无激光导引、患者的体位)和患者相关因素(性别、年龄、有无肺气肿)对诊断正确率的影响。结果①435例病变最终诊断289例为恶性1、46例为良性,CT导引下穿刺活检诊断正确率为83.4%(363/435)。单因素统计分析显示CT导引下穿刺活检对良、恶性病变诊断正确率分别为72.6%(106/146)和88.9%(257/289),χ2=18.71,P=0.00002;激光组和非激光组诊断正确率分别为88.4%(130/147)和80.9%(233/288),χ2=4.00,P=0.0456;诊断正确组和非正确组病灶大小分别为(3.78±1.64)cm和(3.02±1.26)cm,F=13.79,P=0.0002。②应用多元逐步Logistic回归分析病灶的良恶性(Waldχ2=14.01,P=0.0002)、有无激光导引(Waldχ2=3.92,P=0.0477)被列入回归方程。结论病灶的良恶性和有无激光导引是影响CT导引下肺内病变穿刺活检诊断正确率的主要因素。     

CT导引下经皮肌肉骨骼病变穿刺活检

目的 探讨CT导引下经皮穿刺活检在肌肉骨骼病变诊断的价值，评估激光导引装置在肌肉骨骼病变CT穿刺活检中的作用。方法 165例CT引导下肌肉骨骼穿刺活检病例（其中36例使用Pinpoint激光引导系统），骨骼穿刺活检142例，软组织穿刺活检23例。149例有手术病理、切开活检病理或临床随访资料。结果 165例肌肉骨骼病变的穿刺活检总正确率为75．2％（124／165）。其中骨骼病变穿刺活检的正确率为73．2％（104／142），肌肉软组织病变穿刺活检的正确率为87．0％（20／23）。Pinpoint激光导引下CT穿刺活检的诊断正确率为80．6％（29／36）。使用骨钻针穿刺诊断正确率73．8％（96／130），使用抽吸针穿刺诊断正确率80．0％（28／35）。大病灶（直径〉3cm）穿刺活检诊断正确率80．6％（79／98），小病灶（直径≤3cm）穿刺活检诊断正确率67．2％（45／67），二者之间差异有统计学意义（P〈0．05）。结论 CT导引下经皮骨骼肌肉活检是一种安全、简便、有效的诊断和鉴别诊断方法。对大病灶的诊断正确率优于较小病灶，在小病灶中，使用Pinpoint激光导引装置有助于提高诊断正确率。     

透视引导经皮细针穿刺活检肺癌假阴性的相关因素分析

目的探讨肺癌病灶经皮细针穿刺抽吸活检假阴性结果产生的相关因素和避免方法。资料与方法回顾性研究60例在电视透视下(有1例加用CT引导)行经皮针吸肺活检的病例．追踪肺穿刺细胞学结果与手术病理或临床随访结果。分类记录假阴性病灶的操作人员、病理结果、术中发现和病灶CT特征。结果发现假阴性14例(20．3％)。恶性病灶直径3～5cm,深度≥4cm,有坏死或继发感染．则易致穿刺假阴性。结论经皮细针穿刺抽吸活检肺内病灶时一定要仔细分析病灶特征并熟练掌握相应的穿刺技巧．尽量避免发生假阴性。     

CT引导肺穿刺活检对不同大小病灶的应用价值

目的:探讨CT引导肺穿刺活检对不同大小病灶的应用价值.材料和方法:回顾性分析CT引导肺部病变穿刺活检184例.病灶按大小分为两组,其中≥3cm者122个,<3cm者62个,分析穿刺活检术对两组病变的诊断正确率和并发症发生率.结果:CT引导肺穿刺活检对肺内大、小病灶的诊断正确率分别为92.6%(113/122)和91.9%(57/62;P>0.05).<3cm病灶的气胸发生率(19.2%)明显高于≥3cm病灶(5.2%;P<0.01),前者出血发生率(44.2%)亦显著高于后者(15.1%;P<0.01).结论:CT引导肺穿刺活检对大、小病灶的诊断准确率均较高,对大病灶活检的安全性高于小病灶.     

CT透视引导下的纵隔小病灶穿刺活检的临床价值

目的探讨CT引导下纵隔小病灶穿刺活检技术及诊断价值。方法42例纵隔小病灶(小于3cm)在CT引导下采用自动切割式活检针穿刺活检。结果42例纵隔肿块穿刺活检病灶取材成功率97.65(41/42)。纵隔肿块穿刺活检的诊断准确率92.3%(39/42),对于恶性病变诊断准确率96.3%(26/ 27),良性病变为86.7%(13/15)。并发气胸2例(4.8%),纵隔少量出血1例(2.3%)。结论CT引导下穿刺活检是安全、有效的诊断手段,对于纵隔病变诊断的准确率高,CT引导下纵隔小病灶穿刺活检对纵隔病变的诊断和治疗具有重要意义。     

CT导向下经皮纵隔病变自动切割活检准确率分析

目的探讨影响CT导向下经皮纵隔病变自动切割活检(automated cutting needle biopsy,ACNB)准确性的相关影响因素。资料与方法回顾性分析89例采用CT导向下经皮纵隔病变ACNB的患者资料,以最终诊断结果为金标准,计算穿刺活检诊断恶性病变的敏感性、特异性、阳性预测值、阴性预测值及准确性。应用χ2检验分析不同病变部位、大小、良、恶性及穿刺次数等对穿刺活检准确性的影响。结果 89例纵隔病变穿刺活检患者中有80例与最终诊断结果相符,穿刺活检诊断恶性病变的敏感性、特异性、阳性预测值、阴性预测值、准确性及其95%可信区间分别为90.5%(84.4%～96.6%)、86.7%(79.6%～93.8%)、97.1%(93.6%～100%)、65.0%(55.0%～75.0%)、89.9%(83.6%～96.2%)。经统计学分析,经皮纵隔病变ACNB活检准确性与病灶大小、穿刺次数有统计学意义,穿刺层面病灶越大,活检准确性越高;穿刺次数为3次组活检准确性高于<3次组,而与>3次组无明显差异。结论 CT导向下经皮纵隔病变ACNB对纵隔病变定性诊断准确性高且安全,纵隔病变大小及活检次数可影响活检诊断的准确...     

Stress MR imaging for evaluation of popliteal artery entrapment

The popliteal artery entrapment (PAE) syndrome has been recognized as a cause of arterial occlusion in young people. It is the result of an anomaly of the relationship between the popliteal artery and the gastrocnemius muscle. Eight young healthy volunteers (16 legs) and six patients (10 legs) with suspected PAE underwent magnetic resonance (MR) imaging. Gradient-echo images were obtained in axial planes with the leg at rest and during active plantar flexion against resistance. Imaging at rest allowed identification of PAE signs in only one leg, which had an anomalous medial course of the popliteal artery. In the other cases, only the stress technique was able to show signal loss in the popliteal artery due to muscular compression (two legs) or the presence of accessory muscle slip around the vessel (two legs), as confirmed at surgery. MR imaging is therefore a useful technique for the diagnosis of PAE because of its capability of combining information obtainable with other modalities.     

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.     

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     

Uterine contractions: Possible diagnostic pitfall at MR imaging

A total of 206 nongravid patients with various gynecologic problems underwent pelvic magnetic resonance (MR) examinations that included both sagittal T2-weighted and contrast agent–enhanced T1-weighted images. MR images were retrospectively reviewed to identify changes in endometrial configuration on serial images obtained during the same MR examination. In 20 MR examinations (all in women of reproductive age), endometrial distortion due to myometrial bulging was noted on T2-weighted or contrast-enhanced T1-weighted images. It was absent on other MR images obtained at different times. Myometrial bulging exhibited low signal intensity in 18 examinations. The finding resembled adenomyosis or leiomyoma on T2-weighted or contrast-enhanced T1-weighted images. These results evidence the presence of transient myometrial bulging and transient low-intensity myometrium in the nongravid uterus. This phenomenon is thought to represent uterine contraction. Clinicians should be aware of the potential presence of transient low-signal-intensity myometrial bulging that could present diagnostic problems in the normal uterus.     

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.     

Dynamic contrast-enhanced MR imaging assessment of vascularized free fibular grafts

Magnetic resonance (MR) imaging may be a noninvasive method for assessing perfusion of vascularized bone grafts placed for treatment of avascular necrosis. One proximal femur of seven beagles was devascularized, with insertion of a vascularized fibular graft. MR imaging at 1 week (seven dogs) and 6 weeks (five dogs) after surgery included pre- and postcontrast spin-echo sequences, unenhanced twodimensional time-of-flight (TOF) vascular imaging, and dynamic gradient-echo imaging during infusion of gadolinium. Relative signal intensity values of selected regions obtained from the dynamic gradientecho images were plotted as percent enhancement versus time. In the operated hip, MR imaging did not show enhancement in six of seven femoral heads and greater trochanters at 1 week after surgery, with similar results after 6 weeks. MR imaging of fibular grafts 6 weeks after surgery showed an initial rapid increase in enhancement and a subsequent slower increase in five of five dogs, although no enhancement was seen in six of seven dogs at 1 week. These findings contrasted with a rapid initial increase in enhancement followed by slow decline in non-operated hips. Two-dimensional TOP imaging did not show the vascular pedicle of the graft in any dog. Findings of radionuclide bone scanning performed 1 week after surgery were consistent with devascularization of the operated femur and fibular graft. However, tetracycline distribution and histologic findings confirmed the viability of five of five grafts within the devascularized femurs 6 weeks after surgery. Thus, dynamic contrast-enhanced MR imaging at 6 weeks after surgery is valuable for assessing vascular bone graft perfusion, while similar imaging at 1 week may suggest otherwise.     

Adrenal tissue characterization with 0.5-T MR imaging: Value of T2*-weighted images

The authors investigated the value of magnetic resonance (MR) imaging at 0.5 T for distinguishing adrenal adenomas from adrenal metastases. The series included 23 adrenal adenomas (18 nonhyperfunctioning, five hyperfunctioning) and 23 adrenal metastases from various organs. Adrenal tumor–liver signal intensity ratios on T1-, T2-, and T2*-weighted images were calculated for adrenal tissue characterization. Adrenal adenomas were more precisely distinguished from adrenal metastases on T2*-weighted images (21 of 23, 91%) than on T2-weighted images (15 of 23, 65%). T1-weighted images were not useful for this distinction. In conclusion, T2*-weighted images were better than routine T2-weighted images for distinguishing adrenal adenomas from adrenal metastases. It can be postulated that the total signal intensity of adrenal adenomas, which contain some fat components, decreased on T2*-weighted images because of an out-of-phase effect.     

Right-side aortic arch with aneurysm of aberrant left subclavian artery: MR imaging appearance.

Reports of aneurysms of the subclavian artery in both normal and anomalous aortic arches have been rare. The authors describe a patient with a right-side aortic arch and an aneurysm of the aberrant left subclavian artery, which, to the authors' knowledge, is a previously unreported association. At presentation, the aneurysm appeared as a calcified left superior mediastinal mass. Magnetic resonance imaging enabled preoperative diagnosis and guided surgical planning.     

MR angiography of congenital heart disease: Value of segmented two-dimensional inflow technique and maximum-intensity-projection display

Magnetic resonance (MR) angiography of the cardiovascular system was evaluated in 41 patients with congenital heart disease by using a two-dimensional (2D) inflow technique based on a magnetization-prepared gradient-echo pulse sequence with segmented k-space data acquisition and electrocardiographic gating at 0.5 T. Inversion and saturation prepulses were used to suppress stationary tissue and enhance intravascular signal. Presaturation slabs were applied where certain vascular structures had to be suppressed. Sequence parameters were optimized by evaluating signal intensity and contrast characteristics for various flip angles and inversion and saturation delay times. The heart and intrathoracic vasculature were encompassed with 40–50 overlapping sections. Both 2D angiograms and maximum-intensity-projection images were evaluated. Combining data sets acquired in the sagittal and transverse orientations provided the most satisfactory information about the pulmonary arteries. The highest signal-to-noise ratios were obtained with a flip angle of 65° and short prepulse delay times. Two-dimensional MR angiography can provide useful diagnostic information but requires a thorough understanding of in-plane and hemodynamically induced signal intensity changes.