CT引导经皮射频消融术对肺部肿瘤的治疗效果

目的评价CT引导经皮射频消融术（RFA）对肺部肿瘤的近期治疗效果,并阐述CT扫描在疗效评价中的作用。方法 34例经临床和病理证实的肺部肿瘤患者,包括原发性肺癌23例（25个病灶）和转移瘤11例（17个病灶）,起初均经CT引导经皮RFA治疗,随后对所有患者的RFA近期疗效利用螺旋CT平扫与增强扫描进行了逐例随访与评价。结果在34例的42个病灶中,RFA导致了35个病灶完全坏死,增强CT表现为肿瘤去血管化,近期随访无复发;7个病灶未完全坏死,增强CT表现为残留肿瘤强化,近期随访有进展。本组患者中未发生与操作有关的严重并发症。结论 RFA对肺肿瘤的治疗具有确切而明显的近期疗效,是一种侵袭性小且安全的方法,而CT平扫与增强扫描可为疗效评价提供可靠信息。     

C臂CT在15例肺部小病灶射频消融术中的应用

目的 探讨C臂CT在肺部小病灶射频消融(RFA)治疗中的应用价值.方法 分析C臂CT引导下15例患者16次肺小病灶RFA的穿刺成功率、术后累积生存率、肿瘤缓解率、并发症发生率及辐射剂量.结果 16例次肺小病灶RFA中,18处病灶穿刺成功率为100％.12例出现并发症,包括气胸2例(均无需穿刺抽气或胸腔闭式引流),咯血3例,胸痛7例.15例患者RFA治疗后的6个月生存率为100.0％,1年生存率为69.0％,2年生存率为60.0％.有影像随访记录的15个病灶中,术后第1次复查(1～3个月)显示肿瘤缓解率(CR+ PR)为53.3％(8/15).手术平均累积剂量及平均有效剂量分别为(187.62±108.46)mGy和(5.50-3.31) mSv.结论 C臂CT在肺部小病灶RFA术中能给术者带来丰富的信息,可提高病灶穿刺成功率,是一种值得推广的影像引导技术.     

肺部肿瘤CT导向氩氦刀冷冻治疗前后的影像表现

目的研究CT导向经皮肺穿刺氩氦刀靶向治疗肺部肿瘤前后的影像表现及临床疗效评价。方法对96例肺部肿瘤患者采用CT引导下经皮肺穿刺氩氦刀靶向治疗。所有患者术前、术后均行CT扫描，测定肿瘤大小及CT值，并分别于术后1、3、6、12个月复查CT。结果原发肺癌82例，肺转移瘤14例，共110个病灶，单病灶89例，多病灶7例。氩氦刀共治疗103次，平均每次治疗1.07个病灶。每次最多治疗3个病灶。肿瘤直径1.2～15.0cm，平均（4.0±2.5）cm。其中瘤灶直径〈2cm12个，≥2～4cm51个，≥4～6cm24个，〉6cm23个。冰球彻底覆盖瘤灶达其边缘外1am者25例。肿块直径〈4am的63个，有效率为100％，≥4～6am的有效率为95．8％（23／24），〉6am的有效率为69．6％（16／23）。肺部肿瘤冷冻后CT可见逐渐增大的低密度类圆形冷冻区，与非冷冻区有明显的界限。冷冻区中心CT值为负值，术后即刻CT值平均下降30～50HU，与术前CT值相比差异有统计学意义（P〈0．01）。氩氦刀冷冻治疗前后肿瘤直径比较，差异有统计学意义（P〈0．05）。直径〈2cm的病灶治疗3个月后均已消失。术后12个月CT复查81个被消融肿块，完全消失16个（19．7％），缩小42个（51．9％），稳定17个（21．0％），增大6个（7．4％），总有效率为92．6％。43个鳞癌和28个腺癌经氩氦刀治疗12个月后疗效差异无统计学意义（X^2=0.05，P〉0.05）。结论肺部肿瘤氩氦刀冷冻治疗后CT影像表现对其疗效的评价有重要参考价值。     

肺部实体肿瘤射频消融治疗的近期疗效观察

目的：通过对肺部实体肿瘤行射频消融（radiofrequequcy ablation,RFA)治疗结果的观察，评价其技术特点、安全性和疗效。方法：45例肺部实体肿瘤患者， 病灶数共54个，在CT引导下行经皮射频消融治疗，随访2－6个月，常规行螺旋CT平扫和增强扫描来观察评价治疗结果。结果：RFA治疗后有48个肿瘤组织发生凝固性坏死，CT表现为肿瘤去血管化征象或合并有体积缩小。6个病变未能控制。结论：RFA作为肿瘤综合治疗的一部分，副作用小、安全，为较好的治疗恶性肺部局限性实体肿瘤的方法。     

肝动脉化疗栓塞联合CT引导热消融治疗肝内胆管癌

目的 探讨rACE联合CT引导热消融(射频/微波)治疗肝内胆管癌(ICC)的疗效及安全性.方法 回顾分析2009年9月至2013年7月用TACE序贯CT引导下RFA/MWA治疗病理诊断的ICC患者14例,18个病灶,病灶最大径(多个病灶取最大径之和)2.2～7.2 cm,平均(4.2±1.4) cm.TACE随访病灶的完全消融率、手术并发症、无瘤生存时间及总生存时间.结果 15个病灶实现了完全消融,肿瘤的完全消融率为83.3％(15/18),中度并发症的发生率为6.2％,无严重并发症及死亡患者.术后随访6-～44个月,平均(16.0±10.3)个月.至随访结束,死亡6例(42.9％,6/14).完全消融患者的中位无瘤生存时间为17个月,全组患者的中位生存时间为20个月,1、2、3年总体生存率分别为82.5％、41.3％及20.6％.结论 TACE联合CT引导热消融可作为ICC治疗的选择之一.     

TACE联合RFA治疗膈下肝脏恶性肿瘤22例

目的 评价TACE联合RFA治疗膈下肝脏恶性肿瘤的安全性和疗效.方法 22例膈下肝脏恶性肿瘤患者共有26个病灶,单例病灶数目≤3个,直径≤5 cm.所有患者先行1～2次TACE术,术后3～5周行CT引导下RFA治疗,RFA术后4～8周复查MRI评价疗效.所有患者随访12 ～ 30个月,观察并发症和疗效.结果 22例患者26个病灶RFA术中未出现任何严重并发症,术后MRI复查22个(84.6％)病灶达到完全消融,4个(15.4％)病灶经2次RFA后达到完全消融.结论 TACE术可使肝脏恶性肿瘤病灶缩小,轮廓更加清晰,联合RFA治疗膈下肝脏恶性肿瘤更加安全、精确、有效.     

CT引导下微波消融术治疗肺转移瘤的临床效果

【摘要】 目的 探讨CT引导下MWA治疗肺转移瘤的临床效果。 方法 回顾性分析2014年1月至2017年7月接受CT引导下MWA治疗的60例肺转移瘤患者的临床资料，评估CT引导下MWA治疗肺部肿瘤的安全性及其临床疗效。结果 60例患者100个病灶术后1个月复查98个病灶完全消融，完全消融率为98.0%。术后1个月内无一例因MWA造成的死亡，12例患者发生并发症，其中3例患者发生咯血，1例胸腔积液，9例气胸，对症处理后均好转。 结论 CT引导下经皮穿刺MWA治疗肺转移瘤是一种安全有效的微创治疗方法。     

螺旋CT在观察经皮肝穿刺射频消融治疗肝脏肿瘤远期疗效中的价值

目的探讨螺旋CT在观察超声引导经皮穿刺射频消融治疗肝脏肿瘤的长期疗效的价值。方法对45例射频消融治疗肝脏肿瘤患者进行一年以上的螺旋CT随访并对其结果进行分析。结果本组原发灶治愈者共40例（88．9％）其病灶直径为5mm～35mm；周边复发共5例（11．1％），其早期（1～3个月）表现为毁损灶边缘可见不均的强化区；6个月后其边缘的稍低密度区在动脉期表现为明显的强化而门脉期则呈低密度。9例患者发生肝脏其它部位的复发。结论螺旋CT随访，尤其是双期扫描对判定病灶的残留和复发有着重要的作用。     

肺部恶性肿瘤射频消融治疗后CT影像学改变

目的:观察分析肺部恶性肿瘤射频消融治疗后CT影像学改变。方法:搜集因肺部恶性肿瘤行CT引导下射频消融治疗的患者226例(共计消融灶233个),分析评价治疗后病灶CT影像学改变。患者中原发性肺癌201例,肺转移癌25例。接受射频消融的病灶直径1.00～10.60cm,平均(4.36±2.45)cm。平均随访时间13.61个月(1～30个月)。结果:215例患者(95.13%)治疗后立即出现消融灶周围肺组织内毛玻璃样改变,多在1个月内吸收;191患者(84.51%)治疗后肿瘤立即出现增大,127例患者(56.19%)出现消融灶内多发小空泡形成。术后51例患者(22.57%)出现空洞,恶性胸水多发生在治疗3个月以后。121例患者(65.05%)在术后第一个月随访时胸部CT提示病灶有增大,46.15%和50.89%的患者在3个月及6个月复查时病灶缩小,之后这一比例开始降低,至12个月时,只有33.64%的患者病灶较上一次评估时缩小,到24个月时这一比例降低到4.35%。结论:病变周围的毛玻璃样改变、空洞形成、多发小空泡形成和胸膜改变是射频消融后最常见的CT改变。体积较大的病灶更可能出现空洞改变,射频消融术后1个月内病灶多出现增大表现,治疗后6个月是病灶缩小最明显的时期,6个月后出现的病灶较上一评估周期增大提示患者肿瘤进展。CT是射频术后疗效评估的有效手段之一。     

经皮射频消融治疗巨大肝癌

目的总结冷循环射频消融(RFA)治疗巨大肝癌的临床疗效和经验。方法采用CT引导下经皮穿刺冷循环RFA治疗巨大肝癌24例,每个病灶进行射频消融1～4次,其中22例患者结合1～6次TACE治疗,术后通过增强CT或MR评价疗效,所有病例随访12～37个月。结果10例病灶完全坏死,余14例病灶大部分坏死,1年生存率83%,中位生存时间20个月,13例患者现仍存活。结论CT引导下经皮穿刺冷循环RFA治疗巨大肝癌安全、有效。     

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.     

MR imaging of disorders of the brachial plexus

The authors evaluated 64 consecutive patients with suspected brachial plexus (BP) abnormalities of diverse cause with magnetic resonance (MR) imaging, using the body coil and a standardized protocol. Of the 43 patients for whom follow-up was available, 25 were suspected of having neoplastic involvement of the BP, nine had sustained injuries, and nine presented with BP symptoms of uncertain cause. MR imaging was 63% sensitive, 100% specific, and 77% accurate in demonstrating the abnormality in this diverse patient population. When patients with neoplastic and traumatic disorders were considered separately, sensitivity increased to 81%, accuracy to 88%, and specificity remained unchanged. In the patients with a clinical diagnosis of idiopathic or viral plexitis, the MR imaging findings were normal, serving to exclude other structural abnormalities. It is concluded that MR imaging is valuable in the assessment of a wide range of BP disorders.     

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.     

MR imaging characteristics of noncancerous lesions of the prostate.

Radical prostatectomy specimens from 53 men with clinical stage A or B prostate cancer were retrospectively reviewed and compared with correlative axial T2-weighted magnetic resonance (MR) images obtained just before surgery. Non-cancerous lesions were evaluated for signal intensity and location. Focal high-signal-intensity areas (n = 72) were present in 81% of patients. The 26% of lesions seen in the central gland all correlated with cystic atrophy. Of the 53 lesions seen in the peripheral prostate, 47 (89%) were cystic atrophy without associated cancer, four (7.5%) cystic atrophy with cancer, and two (3.8%) focal inflammation. Focal low-signal-intensity areas (n = 42) were present in 60% of patients. Of the 31% of lesions in the central prostate, one-fifth correlated with benign prostatic hyperplasia (BPH) and four-fifths with fibrous tissue. Of the 69% of peripheral lesions, 83% corresponded to fibrous tissue, 10% to BPH, and 7% to normal tissue. Mixed lesions (n = 42) were present in 64% of patients; 86% of these were located centrally and 14% peripherally. All mixed central lesions were BPH; the peripheral lesions were areas of combined cystic atrophy and fibrosis. BPH of low or mixed signal intensity can extend into the peripheral prostate and mimic cancer. High-intensity cystic atrophy associated with cancer can mimic normal tissue.     

肾细胞癌的MRI研究进展

肾细胞癌是最常见的成人肾脏恶性肿瘤。近年来，多种功能MRI成像技术（如扩散加权成像、灌注加权成像等）、多参数MRI联合分析以及影像组学等新兴影像处理技术被证实在肾细胞癌的诊断中具有较大的价值。目前，研究热点多集中于良恶性肿瘤的鉴别、组织学亚型的区分、肿瘤分期、预测核分级及判断预后。就MRI新技术及图像处理技术在肾细胞癌中的研究进展予以综述。     

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.     

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.     

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.     

Percutaneous needle biopsy of the spine

The purpose of this review article is to provide a brief overview of the recent literature on the two main types of percutaneous biopsy methods done in the spinal column: fine needle aspiration biopsy (FNAB) and core needle biopsy (CNB). FNAB is the process of obtaining a sample of cells and bits of tissue for examination by applying suction through a fine needle attached to a syringe. Core needle biopsy involves extracting a cylindrical sample of tissue using a large, hollow needle. The decision for needle biopsy is a joint effort between the clinician, pathologist, radiologist, surgeon, and patient. Specific techniques and approaches with varying needle systems are described for each spinal region. Percutaneous image-guided spine biopsy is a safe and effective procedure. It is the procedure of choice in definitive diagnosis of pathologic lesions of the spine.