螺旋CT多层面重建(MPR)在腰椎间盘病变诊断中的应用价值

目的　探讨螺旋CT多层面重建 (MPR)对腰椎间盘病变的诊断价值。方法　经常规扫描和螺旋扫描MPR重建腰椎间盘病变患者共 41例 ,对L3～ 4 、L4～ 5和L5～S1扫描所得结果进行对比观察。结果　 41例经常规扫描患者中有 35例表现为椎间盘膨出或/和突出 ,经螺旋CT扫描MPR重建示有 36例表现为神经根受压、硬膜囊受压或椎间孔骨性狭窄 ,其中常规扫描无异常发现的 6例患者 ,经MPR示椎间盘压迫神经根或椎间孔骨性狭窄致神经根受压。结论　MPR重建在诊断腰椎间盘病变、显示腰椎疾病的原因以及腰椎疾病的鉴别诊断等方面具有重要价值     

螺旋CT多层面容积重建在腰椎峡部裂中的应用研究

目的:探讨螺旋CT多层面容积重建对腰惟峡部裂的诊断价值。方法:选取行腰椎螺旋CT检查的50例腰痛患者资料,根据椎弓有无峡部裂分成峡部裂组(25例,有峡部裂)和对照组(25例,无峡部裂),所得数据资料行t检验。结果:峡部裂主要发生在L5(18例,占72%),腰椎峡部裂常导致腰椎前滑脱(24例,占96%)。峡部裂组椎管矢状径明显大于对照组椎管矢状径,之间有显著性差异(P<0.01),峡部裂组峡部高小于对照组峡部高,之间有显著性差异(P<0.05)。结论:螺旋CT扫描MPVR重建图像可以从骨性和软组织两个方面为临床提供更多影像学信息。     

正常额隐窝区域气房的三维CT观察

目的 观察正常人额隐窝区域气房的分布类型及测定各类型气房的出现率.方法 对于符合病例选择标准的24例正常人,用64层螺旋CT常规扫描鼻窦,然后在图像工作站上进行轴位重建(层厚0.6 mm,层距0.4 mm),并在相同的条件下进行冠状位、矢状位重建,应用图像分析软件观察额隐窝气房的分布类型,并统计各类的出现率.结果 48侧额隐窝区域三维影像中,鼻丘气房出现率为92%.额气房出现率为54%,其中Ⅰ型29%,Ⅱ型10%,Ⅲ型15%,未见Ⅳ型额气房.额隐窝后组气房出现率为83.3%,其中眶上筛房出现率为35%,额泡气房出现率为15%,筛泡上气房出现率为33.3%.额窦间隔气房出现率为19%.同侧鼻丘气房与额隐窝后组气房的同时出现率为79.2%.结论 多层螺旋CT对分析复杂的额隐窝区域气房及制定手术方案提供很大的帮助.     

下腰段侧隐窝狭窄影像学诊断的解剖学基础

用31具成尸的腰骶段脊柱,观测了L_(3、4、5)神经根在侧隐窝内的走行,穿硬脊膜和椎间孔的位置及其对应关系。对其中10具整尸的下腰段椎间盘进行了CT扫描。本文提出对疑有侧隐窝狭窄之患者,应扫描相应椎骨的下份和椎间盘上份,参考数据为矢状径,6mm以上为正常,5～6mm为临界,5mm以下为狭窄。     

合并侧隐窝狭窄的腰椎间盘突出症的临床观察

目的:为了观察合并侧隐窝狭窄的腰椎间盘突出症的临床诊断及疗效;方法:选取资料完整的病例248例,其中合并侧隐窝狭窄的166例。本组病例均行X片、CT、MRI检查以及脊柱快速主动屈伸试验检查。结果:术前诊断合并侧隐窝狭窄的仅97例,术后诊断合并侧隐窝狭窄的有166例,漏诊率为42％。随访1～7年,平均3年8个月。术后症状完全消失的126例,症状部分消失21例,无变化及加重的19例。再次手术12例。结论:临床上,腰椎间盘突出症合并侧隐窝狭窄的发病率较高,手术时不可忽视侧隐窝的减压。     

腰椎间盘突出CT诊断与手术的关系（附67例报告）

本文报告使用CT诊断腰椎间盘突出67例，根据不同的病变特点，分别采用开窗式，半椎板式，全椎板式和显微外科方法摘除椎间盘髓核，切除肥厚黄韧带或扩大狭窄侧隐窝或切除椎体后骨赘。手术证实稚间盘突出62例，CT诊断符合率为92．5％。而黄韧带肥厚．侧隐窝狭窄和椎体后骨赘则完全符合。治疗效果比较满意，优良率为91．7％。     

256层螺旋CT一站式重建诊断颈椎病的临床应用

目的探讨256层螺旋CT一站式重建诊断颈椎病的应用价值。资料与方法对500例临床拟诊为颈椎病的患者进行颈椎容积扫描后在EBW4.0工作站进行模拟常规椎间盘扫描重建及一站式重建[包括容积再现(VR)、多平面重组(MPR)及曲面重组(CMPR)],分别观察并比较两种扫描模式对颈椎曲度、颈椎序列、颈椎椎体骨质增生、椎小关节异常、钩椎关节增生、骨性椎管狭窄、横突孔异常、椎间隙变窄、侧隐窝狭窄、椎体许氏结节、椎间盘异常、椎旁软组织异常、神经根受压、前后纵韧带骨化、项韧带骨化等颈椎病相关的15项征象的显示能力。结果两种重建模式下,椎旁软组织异常(P=0.500)、颈椎序列异常(P=0.499)、横突孔异常(P=0.685)、侧隐窝狭窄(P=0.447)、项韧带骨化(P=0.346)差异无统计学意义,其余观察指标差异均有统计学意义(P<0.05)。结论 256层螺旋CT颈椎一站式重建能够准确地显示更多的颈椎病相关征象,为临床准确诊断提供更多有效的影像信息。     

侧隐窝注射治疗腰椎管狭窄临床疗效观察

目的:探讨侧隐窝注射治疗腰椎管狭窄临床疗效观察。方法:选择2008年～2010年在我院进行治疗的腰椎管狭窄60例患者作为研究对象,年龄分布61.5±13.2岁,男41例、女19例。所有患者均经MR或CT明确诊断为腰椎管狭窄,按照单纯随机的方法分为两组,分别为A组和B组,每组30例。两组患者在年龄,病情、临床表现和性别分布没有统计学意义(P0.05),说明两组患者具有可比性。所有患者均签署知情同意书,愿意参加本研究。选择SPSS13.0统计软件进行统计描述与分析。结果:研究显示干预后显示B组5d缓解率、9d缓解率和14d缓解率在疼痛感觉中明显优于A组(P0.05),实验前后两组比较均存在统计学意义(P0.05),研究显示经过有针对性的治疗和干预后显示B组5d缓解率、9d缓解率和14d缓解率在直腿抬高实验中明显优于A组(P0.05),实验前后两组比较均存在统计学意义(P0.05),研究显示B组在总有效率明显多于A组(P0.05)。结论:采用侧隐窝注射治疗腰椎管狭窄临床疗效较好,应加强临床推广。     

CT旁矢状位重建对腰椎间孔狭窄的诊断价值

目的探讨螺旋CT旁矢状位重建对腰椎间孔狭窄的诊断价值。方法2003-01～2004-04,对腰腿疼患者临床和常规CT检查考虑有椎间孔狭窄时,使用螺旋CT旁矢状位二维重建,诊断并手术腰椎间孔狭窄症15例。结果15例螺旋CT旁矢状位重建均显示有L4～5或L5～S1椎间孔狭窄,2例极外侧型椎间盘突出,8例椎体终板后外缘局限性增生骨化突入椎间孔,1例腰椎滑脱峡部裂假关节,4例后外侧椎间盘突出间隙狭窄并黄韧带肥厚小关节增生、上移。水平狭窄型7例,垂直狭窄型8例。Ⅱ度狭窄6例,Ⅲ度狭窄9例。结论螺旋CT旁矢状位重建可以弥补常规横断CT扫描的不足,对椎间孔显示清晰直观,对手术减压有定位指导意义,有较高诊断价值。     

腰椎间孔上隐窝狭窄的旁正中矢状面CT影像学

目的：提高对腰椎间孔上隐窝狭窄在旁正中矢状面CT改变的认识。材料和方法：对100例腰椎间孔上隐窝狭窄病人进行螺旋CT扫描，并进行旁正中矢状面CT重建，在腰椎旁正中矢状面观察腰椎间孔上隐窝狭窄的形态学改变。结果：腰椎间孔上隐窝狭窄在旁正中矢状面CT图像上表现为：①椎间隙变窄，造成椎间孔上下变窄，占63％。②上关节突增生、肥大及骨赘形成，造成椎间孔上隐窝前后变窄，占20％。③椎体上、下缘骨赘形成，造成椎间孔上隐窝变窄，占10％。④椎体前下滑移，导致椎间孔上下隐窝错位，引起椎间孔上隐窝狭窄，占7％。结论：旁正中矢状面CT重建图像在观察腰椎间孔上隐窝狭窄比常规CT横断面更敏感。能充分显示腰椎间孔上隐窝狭窄的形态学改变，为腰椎间孔上隐窝狭窄的诊断提供可靠的影像学根据。     

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.     

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 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.     

Dynamic MRI of the gallbladder lesions: Differentiation of benign from malignant

Forty-nine pathologically proven gallbladder lesions were evaluated in 45 patients using dynamic MRI with a spoiled gradient pulse sequence (SPGR), to access the ability of this technique to differentiate benign from malignant gallbladder lesions. The studies were reviewed retrospectively. Signal intensity of the lesions were measured. Twenty-one malignant and 28 benign lesions were classified into three categories: polypoid, diffuse wall thickening, and exophytic. Early and delayed enhancement patterns were evaluated. For the polypoid masses, malignant lesions (n = 9) demonstrated early and prolonged enhancements, whereas benign lesions (n = 14) had early enhancement with subsequent washout (P < .05). For diffuse gallbladder wall thickening, malignant lesions (n = 6) demonstrated early and prolonged enhancement and benign lesions (n = 14) showed relatively slow, prolonged enhancement (P < .05). The exophytic masses (n = 6) all were malignant and demonstrated early and prolonged enhancement. Dynamic MRI can help differentiate benign from malignant gallbladder lesions.     

Techniques for high-resolution MR imaging of atherosclerotic plaque

Atherosclerotic cardiovascular disease is the most common cause of death in the United States. Investigation of atherosclerotic plaque morphology and composition is important because the findings may be useful in predicting prognosis or response to therapy. This study presents high-resolution magnetic resonance (MR) imaging techniques developed on a 1.5-T whole-body imager with a custom-built surface coil, for characterizing the composition and morphology of plaque removed at carotid endarterectomy. The initial comparison of MR imaging and histologic results showed good correlation. In conjunction with MR angiography, these techniques could be used in in vivo imaging to define the size, location, and contents of atherosclerotic plaque at the carotid bifurcation.