Community-acquired necrotizing fasciitis caused by Acinetobacter calcoaceticus: A case report and literature review

A 61-year-old man presented with pain in the abdomen and right lower limb. He had a history of hepatitis B virus-induced liver cirrhosis, but had not been visiting the outpatient clinic and did not receive any medication. Cutaneous necrosis and bulla were observed on his abdomen and right lower limb. The necrotic skin was incised, and he was diagnosed with necrotizing fasciitis. A nonfermentative Gram-negative bacillus infection was confirmed from aspirated fluid and blood cultures. Therefore, meropenem and immunoglobulins were administered. Because necrosis was widespread, surgical debridement was performed. Thereafter, Acinetobacter calcoaceticus infection was confirmed by semi-quantitative PCR using the bullous fluid and blood cultures. Meropenem was administered for 3 weeks, followed by levofloxacin alone for 1 week. The patient's condition improved; therefore, skin grafting was performed as planned and yielded a favorable response. After rehabilitation, the patient could walk without support and infection did not recur. However, he had severe liver cirrhosis and large esophageal varices, and he eventually died from sudden varix rupture.Necrotizing fasciitis is an uncommon soft tissue infection, associated with high morbidity and mortality, and early recognition and treatment are crucial for survival. Acinetobacter is rarely associated with necrotizing fasciitis. Although this is a very rare case of the occurrence of necrotizing fasciitis due to A. calcoaceticus infection, we believe that this organism can be pathogenic in immunocompromised patients such as those with liver cirrhosis by reporting this case.     

The value of intraoperative ultrasound during hepatic resection compared with improved preoperative magnetic resonance imaging

BACKGROUND: Patients with colorectal metastases confined to the liver may be cured by resection. Combined bimanual palpation and intraoperative ultrasound (IOUS) augment the detection of colorectal hepatic metastases. The importance of IOUS in the surgical management of hepatic tumors has been demonstrated and should arguably be considered the final diagnostic procedure. OBJECTIVE: To determine the relevance of routine IOUS prior to hepatic resection compared with improved preoperative Magnetic resonance imaging (MRI). PATIENTS AND METHODS: Eighty patients with metastatic colorectal adenocarcinoma underwent hepatic resection between 1998 and 2001. The IOUS results were compared with preoperative MRI, bimanual palpation, and resection histopathology. The preoperative surgical plan was compared with the surgical procedure performed. Data were retrospectively analyzed. RESULTS: IOUS provided additional useful information not available preoperatively for 37 (47%) patients, including the identification of subcentimetre metastatic lesions, characterization of the lesion, and the anatomy of the hepatic vasculature. The preoperative surgical plan was changed secondary to the IOUS findings alone in 14/80 (18%) patients. IOUS did not provide any additional useful information for 43 (53%) patients. A correlation was demonstrated between the preoperative diagnosis, intraoperative findings, and resection histopathology. CONCLUSION: Accurate diagnostic studies facilitate critically decisive actions during planned hepatic resection(s). The current findings suggest that IOUS provide the most useful additional information for hepatic lesions, despite recent improvements in preoperative MRI scanning. Furthermore, routine IOUS should be employed during hepatic resection for colorectal metastases.     

Choledochocele: diagnosis by magnetic resonance imaging

The value of magnetic resonance imaging (MRI) and magnetic resonance cholangiopancreatography (MRCP) is demonstrated in a case of a 22-year-old female with a small choledochocele clinically presenting with acute cholecystitis and pancreatitis. Previous abdominal sonography and computed tomography were not diagnostic. MRI and MRCP showed a cystic dilatation of the distal common bile duct, intramurally located in the second portion of the duodenum and protruding into the duodenal lumen. These findings allowed a confident diagnosis of a choledochocele. Received: 8 December 1999/Accepted: 12 January 2000     

评估MRI在直肠癌术前TN分期价值

目的:评价MRI技术在直肠癌术前TN分期中的诊断价值。方法:对60例直肠腺癌患者用MRI振进行TN分期,并与病理结果对照,用κ统计分析法处理结果。结果:MRI检测T分期患者直肠壁浸润深度的灵敏度为77.8%,特异度81.8%,准确度80%,经统计分析证实MRI术前其分期与病理分期结果的一致性中等(κ值为0.596);MRI检测N分期患者直肠壁浸润深度的灵敏度为85.3%,特异度69.2%,准确度78.3%,经统计分析证实MRI术前分期与病理分期结果的一致性中等(TN分期κ值分别为0.596和0.553);结论:MRI可较准确地评估直肠肿瘤浸润深度和淋巴结转移情况,并作出较准确的直肠癌术前TN分期。     

心血管MRI第一部分--磁共振基本物理原理及成像策略

MRI以其独特的优势广泛应用于临床,特别是在心血管系统疾病中的诊断价值得到日益体现。心血管MRI(CMR)能无创地一站式评价心血管的解剖、功能、心肌灌注和病变的组织特性,并且评价的可重复性高。CMR成像技术内容丰富,尚具挑战性,需克服心脏自身和随呼吸的运动伪影。MRI的软硬件系统性能不断提高,特别是磁场强度革命性地提升,使得成像技术不断地完善和更新。作者用4个篇章分别阐明上述MRI尤其是CMR的基本成像原理及技术要点,致力于用简明易懂的语言使大多数放射科一线工作者能轻松愉悦地领悟MRI尤其是CMR的魅力。此文为第一部分,归纳MRI基本物理原理及MR图像的产生过程。     

Left-sided superior vena cava: diagnosis by magnetic resonance imaging

We describe a case of left-sided superior vena cava. The diagnosis was suggested by chest radiograph after central venous catheter placement. This was subsequently confirmed by magnetic resonance imaging. Received: 4 March 1997 Accepted: 21 March 1997     

3.0T磁共振诊断腹膜后神经鞘瘤1例

患者男,46岁,体检发现腹膜后肿物,MRI扫描示左中腹部见一巨大软组织异常信号影,T2为混杂信号,其内可见不规则长T2信号,T1以等信号为主,大小约10.0 cm×7.0 cm×6.0 cm,境界清晰,周围肠管可见挤压征;增强后,该病灶均匀强化,边缘似可见包膜,延迟期病灶内部仍可见无强化区.术后病理诊断:腹膜后神经鞘瘤,瘤细胞丰富,局灶生长活跃,核分裂象1～3个/10HPF,间质内可见较多慢性炎细胞及泡沫细胞浸润.免疫组化染色显示肿瘤细胞:Bcl-2(灶状+),CD34(-),CD68(+吞噬细胞),CD99(+)、S-100(++),SMA(-),CD117(-),actin(pan)(-).     

多模态磁共振成像技术在胶质瘤细胞增殖诊断中的应用

脑胶质瘤是一种临床发病率高、预后不良的恶性肿瘤,目前其术前诊断分级及预后评价仍缺乏有效的方法。多模态磁共振成像技术能够反映肿瘤的组织病理学变化,细胞增殖是肿瘤发生、发展的关键行为,与肿瘤的临床诊断、分级、治疗及预后密切相关。本文就多模态磁共振成像技术在脑胶质瘤细胞增殖诊断方面的应用进展予以综述。     

磁共振成像在布鲁氏杆菌性脊柱炎诊断中的应用价值

目的探讨布鲁氏杆菌性脊柱炎的MRI表现,旨在提高对该病的认识,从而提高布鲁氏杆菌性脊柱炎的诊断及鉴别诊断水平。材料与方法回顾性分析我院2015年1月至2017年4月间65例由临床确诊为布鲁氏杆菌性脊柱炎患者的MRI图像,分析其好发部位、椎体形态、各序列信号特征及周围组织情况。结果布鲁氏杆菌性脊柱炎常见于腰椎,多累及椎体前部及中部。其中41例(63.1%)病变椎体形态变化不明显,T1WI显示为低信号,T2WI显示为等或高信号影,精确频率反转恢复(spectral presaturation attenuated inversion recovery,SPAIR)序列为高信号,增强扫描明显强化。53例(81.5%)椎间隙狭窄。58例(89.2%)椎管外软组织受累,椎旁脓肿58例(89.2%),硬膜外脓肿17例(26.2%),脓肿呈不均匀长T1、长T2信号,SPAIR序列呈边界模糊的混杂高信号,内含大小不等、壁厚薄不均且壁明显强化的脓腔。28例(43.1%)患者出现伴随征象,包括椎小关节炎、前纵韧带和棘间韧带钙化。结论布鲁氏杆菌性脊柱炎的MRI表现具有特征性,MRI对诊断及鉴别诊断该病具有重要价值,其中SPAIR序列去除脂肪组织的干扰,可以较敏感地发现病灶,对于病灶及周围情况的显示具有重要意义。     

MRI增强扫描在肛周脓肿术前诊断中的价值

目的探讨MRI不同方位及序列成像,尤其是冠状位及轴位T1WI压脂增强序列在肛周脓肿的术前诊断中的价值。方法经手术证实的30例脓肿患者全部进行增强MRI扫描。以手术结果为对照标准,统计分析MRI扫描三种序列组合对各种类型肛周脓肿及内口的检出率,并与直肠指诊进行对照分析。结果 30例患者手术证实52个脓肿,30个内口。直肠指诊肛周脓肿43个,检出率为82.69%,其中括约肌间脓肿15个,坐骨肛管间隙脓肿23个,肛提肌上方脓肿5个,正确的内口22个,检出率为73.33%。MRI轴位联合冠状位T1WI压脂增强序列检出肛周脓肿52个,检出率最高为100%,其中括约肌间脓肿18个,坐骨肛管间隙脓肿23个,肛提肌上方脓肿11个,正确的内口29个,检出率为96.67%。两组比较,对于肛提肌上方脓肿和内口的检出有统计学意义(P值分别为0.017和0.030)。结论肛周脓肿术前MRI增强扫描,能发现更多的肛提肌上方脓肿及明确的内口,为外科手术方式的选择提供更可信的影像资料。     

常规MRI联合PWI对前列腺癌的诊断价值研究

目的探讨良性前列腺增生（benign prostatichy perplasia,BPH）及前列腺癌（prostate carcinoma,PCa）磁共振成像（MRI）和磁共振灌注加权成像（PWI）表现以及灌注值,评价两者对BPH和PCa的诊断及鉴别诊断价值。方法对临床诊断为前列腺疾病的76例患者行常规MRI及PWI扫描,分析BPH及PCa的常规MRI表现及所获得时间-信号曲线（TIC）,计算最大灌注斜率（SSmax）。结果 35例PCa及41例BPH的TIC均有明显的上升支,较之BPH组,PCa组TIC上升支较陡峭,峰值高,达峰时间短;PCa组的SSmax高于BPH组（P〈0.05）。结论 MRI与PWI联合应用有助于PCa的诊断与鉴别诊断。     

核磁共振技术在心肺复苏中对脑功能的评价及应用

心搏骤停心肺复苏成功后脑功能的恢复,以及对患者预后的评价已经成为临床医务人员越来越关注的问题.在评价复苏成功后各种治疗措施的疗效和患者的预后方面,核磁共振技术以其独特的优势,为研究提供重要帮助.     

Magnetic resonance imaging of cerebral fat embolism: A case report

Fat embolism syndrome (FES) is one of the most important causes of morbidity and mortality following multiple fractures. Neurological involvement (cerebral fat embolism) has been reported frequently. A case of cerebral fat embolism is reported. While CT scan revealed no abnormalities, MRI, performed in this patient 8 days after trauma, showed relative lowintensity areas on T1-weighted images and high intensity areas on T2-weighted images involving cerebral white matter, corpus callosum and basal ganglia. MRI follow-up (1 and 3 months post-trauma) showed nearly complete resolution of the abnormal signal. MRI seems to be a useful diagnostic tool for detecting and quatifying lesions in fat embolism syndrome.     

Active lower gastrointestinal hemorrhage diagnosed by magnetic resonance angiography: case report

Contrast-enhanced magnetic resonance angiography (MRA) has demonstrated the potential for detecting gastrointestinal bleeding in animal studies. We report a case of active lower gastrointestinal bleed diagnosed with MRA in an elderly patient. Clinical, radiologic, and surgical findings are described.     

心血管MRI第二部分--心血管MRI的基本序列和常用技术

此文为第二部分,着重介绍心血管MRI(CMRI)的基本对比、序列及要求。首先,归纳CMRI的三种基本快速成像序列和图像的对比分类。然后,应对CMRI的技术挑战和难点,讲述CMRI质量控制的常用技术。     

磁共振弥散加权成像在直肠癌检查中的价值

直肠癌是最常见的恶性肿瘤之一。在我国,其发生率呈逐年上升趋势,严重影响人们的健康和生活质量。准确的术前分期是选择最佳治疗方案和手术方式所必须的。MRI(磁共振成像)是目前最常用的影像学方法之一,DWI(弥散加权成像)能更好地显示病变,判断肿瘤浸润程度及淋巴结转移,评估术前放化疗疗效,对临床有重要意义。     

磁共振成像在诊断幼年特发性关节炎中的应用

目的:探讨幼年特发性关节炎(JIA)患者膝关节磁共振成像(MRI)的主要表现及检查技术要点。方法:探讨T1加权自旋回波序列(T1W/SE)、T2加权快速自旋回波序列(T2W/TSE)、增强后T1W脂肪抑制三维快速梯度回波序列(SPIR/3D/FFE)等技术及其在膝关节MRI中的作用,并分析42例JIA患儿的膝关节MRI表现。结果:增强后T1脂肪抑制三维快速梯度回波序列结合T1W、T2W序列能综合评价JIA造成的关节病变程度,其主要表现包括滑膜增生、血管翳形成、关节腔渗出积液、骨髓水肿、半月板变性、关节软骨破坏、腘窝淋巴结肿大等。结论:增强后T1脂肪抑制三维快速梯度回波序列结合传统T1W、T2W成像对判断JIA膝关节病变有重要价值。     

磁共振成像新技术在诊断卒中后抑郁方面的应用

当前卒中后抑郁（post-stroke depression,PSD）作为脑卒中后常见的并发症越来越受到人们的关注,但是 PSD 的发病机制、病理定位、诊断标准等尚不明确,PSD 患者极易被漏诊或误诊。近年来MRI 技术飞速发展产生了一系列新的成像技术,它们可以从血流灌注、生理结构、生物代谢等方面反映大脑功能和结构的变化,并且具有无创性、无放射性、时间空间分辨率高、脑功能区定位准确等特点,在PSD的发病机制、病理定位、早期诊断及疗效评价等方面应用潜力巨大。     

Dendritic PARACEST contrast agents for magnetic resonance imaging

MRI contrast agents based on chemical exchange‐dependent saturation transfer (CEST), such as Yb(III)DOTAM complexes, are highly suitable for pH mapping. In this paper, the synthesis of Yb(III)DOTAM‐functionalized poly(propylene imine) dendrimers is described. The applicability of these dendritic PARACEST MRI agents for pH mapping has been evaluated on a 7 T NMR spectrometer and on a 3 T clinical MRI scanner. As expected, based on the different numbers of exchangeable amide protons, the lowest detectable concentration of the first and third generation dendritic PARACEST agents is by a respective factor of about 4 and 16 lower than that of a mononuclear reference complex. The pH dependence of the CEST effect observed for these compounds depends on the generation of the poly(propylene imine) dendrimer. Upon going to higher generations of the Yb(III)DOTAM‐terminated dendrimer, a shift of the maximum CEST effect towards lower pH values was observed. This allows for a fine‐tuning of the responsive pH region by varying the dendritic framework. Copyright © 2007 John Wiley & Sons, Ltd.