Gliomatosis cerebri: a case report with autopsy correlation

Summary MRI-autopsy correlation in a case of gliomatosis cerebri suggests that poor gray-white matter demarcation on MRI may be sign of neoplastic infiltration. The extent of infiltration is imperfectly assessed by current imaging modalities.     

Focal lung uptake of Gallium-67 in patients with acquired immunodeficiency syndrome secondary to pneumocystis carinii pneumonia

It is generally accepted that the lung uptake of ⁶⁷Ga in patients with pneumocystis carinii pneumonia (PCP) is diffuse and bilateral. Three cases of focal lung uptake of ⁶⁷Ga in AIDS patients with PCP but without other opportunistic infection are described. While focal lung uptake is characteristic of opportunistic infections other than PCP, we wish to emphasize that focal uptake of gallium in the chest does not rule out PCP and may represent its earliest stage of presentation.     

The future of cardiovascular imaging and non-invasive diagnosis

Advances in medical imaging now make it possible to investigate any patient with cardiovascular disease using multiple methods which vary widely in their technical requirements, benefits, limitations and costs. The appropriate use of alternative tests requires their integration into joint clinical diagnostic services where experts in all methods collaborate. This statement summarises the principles that should guide developments in cardiovascular diagnostic services.This paper is published simultaneously in the European Heart Journal (2006;27:1750–1753) and in the European Journal of Echocardiography (2006;7:268–273).     

结节性硬化症多器官损害7例报告

目的探讨结节性硬化症多器官损害的临床特点以提高诊断治疗水平。方法回顾性分析7例结节性硬化症伴皮肤、大脑、肾脏、肝脏等多器官损害患者的临床资料,探讨其特征性临床表现及影像学改变。结果7例患者均有多器官损害,累及两个器官3例,3个及以上器官损害4例;皮肤损害主要为面部血管纤维瘤6例,皮肤色素脱失斑7例,鲨鱼皮斑3例,趾甲下纤维瘤1例;癫痫发作6例,智力低下4例,颅脑CT或MRI检查提示室管膜下结节4例,皮质结节2例;4例合并双侧肾脏多发错构瘤,1例合并肝脏错构瘤。结论特殊的皮肤损害、癫痫发作、智力低下,脑CT或MRI检查提示室管膜下结节或皮质结节或内脏多发性错构瘤为本病的主要临床特征,提高本病的认识有助于早期诊断和治疗。     

大鼠肾上腺髓质增生MRI与病理的对比研究

目的通过 MRI 研究大鼠肾上腺髓质增生(AMH)的信号特征,并与病理结果对比,探讨 MRI 诊断大鼠 AMH 的可能性。方法雄性 SD 大鼠60只,依体重大小,采取随机排列表法随机分为 A、B、C 实验组,皮下注射利血平0.4 mg·kg~(-1)·d~(-1);a、b、c 对照组,皮下注射等量生理盐水,每组10只。A、a,B、b,C、c 组分别连续注射40、60和80 d,行肾上腺 MR 扫描,并和病理研究作对照。结果注射60 d 后 B 组髓质百分数(34.3±5.8)%高于 b 组(25.7±8.9)%(t=2.462,P<0.05),C 组(36.4±7.8)%也高于 c 组(24.8±7.9)%(t=3.104,P<0.01),利血平注射60 d 后 AMH 造模成功;MR 下 B 和 b 组、C 和 c 组肾上腺体积分别为(50.7±14.1)和(41.1±11.0)、(52.7±10.5)和(40.4±10.7)mm~3,差异有统计学意义(t 值分别为2.352、3.442,P 值分别<0.05、<0.01);MR 下中心髓质区 T_2WI 信号 B 组高于 b 组(Z=-3.786,P<0.01)、C 组高于 c 组(Z=-3.570,P<0.01);光学显微镜(简称光镜)下见 B 和 C 组髓质明显增厚,细胞数增多、密集,呈实质性片状或条索状分布,形成细胞巢;实验组部分大鼠 T_1WI 下外周皮质信号明显增高,光镜下见束状带增生,细胞呈空泡状肥大,富含脂质。结论 MRT_2WI 中心髓质区信号增高及 T_1WI 外周皮质高信号可能对于诊断大鼠肾上腺髓质增生有意义。     

adaptive fourier threshold filtering: A method to reduce noise and incoherent artifacts in high resolution cardiac images

We introduce an image processing method which reduces white noise and random artifacts in sets of high resolution, time resolved images. At each pixel, the processing consists of: (1) the isolation of a time intensity curve (TIC), (2) Fourier transformation of each TIC, (3) application of a threshold to remove low intensity coefficients, (4) inverse transformation to generate noise reduced TICS which are recombined to form images with improved signal-to-noise ratio (SNR). Noise filtering by Fourier thresholding is demonstrated on a set of cardiac images, resulting in a reduction of the noise energy by approximately 90%.     

Mesenteric cyst with milk of calcium

A mesenteric cyst with milk of calcium in an adult patient is presented. Preoperative evaluation included plain film, ultrasound, computed tomography (CT), and magnetic resonance imaging (MRI). To our knowledge, the presence of milk of calcium in a mesenteric cyst has not been previously described.     

Reperfused myocardial infarctions on T1- and susceptibility-enhanced MRI: Evidence for loss of compartmentalization of contrast media

The purpose of this study was to characterize the contrast caused by a susceptibility MRI contrast agents, on spin echo T₂-weighted imaging of reperfused myocardial infarction. Our interest in this model focused on the expected requirement that such agents be compartmentalized in the tissue to cause signal loss on spin echo images, a condition which may not be present in reperfused infarcted myocardium. Accordingly, nine rats were subjected to 2 h of left coronary artery occlusion followed by 3 ± 0.5 h of reperfusion prior to administration of contrast media. Three sets of MR images were acquired: (a) baseline axial images at the midventricle, both T₁-weighted (TR/TE = 300/20) and T₂-weighted (TR/TE = 1500/60); (b) T₁-weighted images after administering a T₁-enhancing agent, Gd-DTPA-BMA (0.2 mmol/kg), to document that contrast media is delivered to the reperfused infarction; and (c) T₂-weighted images after administering the susceptibility agent, Dy-DTPA-BMA (1.0 mmol/kg). Gadolinium-enhanced T₁ images depicted reperfused infarction as regions with greatly enhanced signal intensity compared with unin-farcted myocardium, indicating that contrast agent was delivered to the infarcted zone. Dysprosium-enhanced T₁ images depicted the injury as a region of persistent signal intensity relative to depletion of signal in normal myocardium, consistent with failure of the contrast agent to cause signal loss. Similar infarction sizes were observed for unenhanced T₂-weighted images (33 ± 5%), gadolinium-enhanced T₁ weighted images (36 ± 5%) and postmortem staining (30 ± 6%); strong correlations (r > 0.9) were noted in comparisons of these data. Dysprosium-enhanced images exhibited a smaller region of differential signal presumed to be infarction (20 ± 5%, P < 0.05) and weak correlations (r < 0.75) with the other measurements. We conclude that the smaller infarction depicted on dysprosium-enhanced images is a subregion of the true infarction in which myocardial necrosis is sufficiently advanced that the agent is homogeneously distributed throughout all tissue compartments, preventing T₂*-dependent phase loss on spin echo images.     

椎管内肿瘤磁共振成像增强扫描初步观察

对１１例手术病理证实的椎管内肿瘤进行磁共振成像（ＭＲＩ）增强扫描的前、后分析，并对肿瘤定位、定性和鉴别诊断作了初步探讨。根据肿瘤形态、边界、强化程度，及与脊髓、硬脊膜、神经根等关系，ＭＲＩ的增强扫描对提高其定位、定性诊断均有较大的帮助。