肝癌患者多层螺旋CT多期扫描的影像特征及临床应用价值

目的:探讨多层螺旋CT对肝癌多期扫描的影像特征及其临床应用价值.方法:临床纳入原发性肝癌患者90例,随机分为研究组与对照组,每组45例.研究组采用多层螺旋CT进行动脉期、全肝静脉期、病灶平衡期扫描,对照组采用119]多层螺旋CT平扫.观察两种扫描方式在病灶显示率及病灶阳性诊断率等方面的差异.结果:研究组CT动脉期、静脉期、平衡期病灶显示率分别为95.56％、91.11％、95.56％,对照组CT平扫显示率为75.56％,研究组各期显示率均要明显高于对照组,差异均有显著性(P＜0.05);研究组诊断肝癌42例,诊断阳性率为93.33％,对照组诊断肝癌26例,诊断阳性率为57.78％,差异有显著性(P＜0.05);对不同类型肝癌诊断率方面,研究组对巨块型、结节型、弥漫型的诊断准确率分别为100.00％、93.10％、87.50％,对照组对巨块型、结节型、弥漫型的诊断准确率分别为100.00％、50.00％、20.00％,其中结节型、弥漫型诊断准确率两组差异有显著性(P＜0.05).结论:多层螺旋CT对肝癌进行多期扫描,能够为早期临床诊断肝癌提供更多的影像诊断信息,有助提高肝癌的早期诊断率.特别对于结节型、弥漫型等类型的肝癌早期诊断,能够提供更为可靠的诊断依据.     

HASTE MRCP and MRI findings in alveolar echinococcosis of the liver

Alveolar echinococcosis is a rare mass‐producing inflammatory process of the liver. Experience with MRI, and particularly magnetic resonance cholangiopancreatography (MRCP), demonstrates that features of this disease are limited. The HASTE (half‐Fourier acquisition single‐shot turbo spin echo) MRCP and MRI findings of alveolar echinococcosis of the liver are presented in this report. HASTE MRCP was used to define the biliary system and the biliary system–mass relationship. It was found that results were comparable with those of invasive techniques such as endoscopic retrograde cholangiopancreatography and percutaneous transhepatic cholangiography.     

Tumour and tumour‐like lesions of the intercondylar notch of the knee: A pictorial review

A variety of tumours and tumour‐like lesions are found in the intercondylar notch of the knee. MR imaging is the technique of choice in evaluating these conditions. Correlation with radiographs is important to identify those lesions containing calcification. This review article discusses the imaging features of tumour and tumour‐like lesions involving the intercondylar notch with an emphasis on MR imaging features that suggest a specific diagnosis.     

正常肝脏CT灌注成像与肝脏储备功能对照研究

目的通过对正常肝脏CT灌注成像与肝脏储备功能对照研究,确定准确的正常肝脏CT灌注值。方法选择无任何肝脏疾病的志愿者20例,采用Philips16排螺旋CT机,选择肝门层面为中心,包括肝门静脉、腹主动脉和脾脏在内进行CT灌注扫描,通过设备附带软件分别计算肝脏的灌注值;利用吲哚氰绿实验进行肝脏储备功能检测。结果20例平均肝脏CT灌注值肝动脉灌注量（HAP）=0.18±0.08 ml/min.ml,门静脉灌注量（HPP）=0.98±0.33 ml/min.ml,总肝灌注量（TLP）=1.1±0.12 ml/min.ml,肝动脉灌注指数（HAI）=19.2%,门静脉灌注指数（PVI）=80.8%;平均15 min吲哚氰绿潴留率（ICGR15）=1.8%。结论肝脏CT灌注成像能反映肝脏的血流动力学变化,可作为影像学评估肝脏储备功能的重要指标。     

Simultaneous positron emission tomography and magnetic resonance imaging for the detection and characterisation of liver lesions in patients with colorectal cancer: A pictorial review

Patients with colorectal cancer undergo frequent diagnostic imaging to stage the extent of metastatic disease and assess response to treatment. Imaging is typically via diagnostic contrast‐enhanced CT or combined FDG‐PET/CT. However, recent research has demonstrated promising benefits of combined FDG‐PET/MRI in oncologic imaging due to the superior soft‐tissue contrast of MRI. The extent of both intrahepatic and extrahepatic disease is important in establishing treatment options for colorectal cancer patients, and FDG‐PET/CT and dedicated liver imaging are often both required. FDG‐PET/MRI offers the advantage of a single examination which can be completed within a similar duration as dedicated liver MRI imaging. This improves patient convenience and anatomical co‐registration between PET and MRI imaging and provides a potential cost benefit. The diagnostic benefits of FDG‐PET/MRI include the simultaneous characterisation of focal liver lesions, exclusion of extrahepatic disease, the detection of additional hepatic metastases and extrahepatic disease, and the multi‐parametric assessment of treatment response. This pictorial review highlights examples of these benefits.     

Temporal changes in magnetic resonance imaging characteristics of Gliadel wafers and of the adjacent brain parenchyma

Carmustine is used in the treatment of glioblastomas as locally applied chemotherapy in the form of biodegradable wafers, which are lined on the walls of the resection cavity at the end of the resection, to increase local concentrations and decrease systemic toxicity. A total of 44 patients with glioblastoma with gross macroscopic tumor removal were included. MRIs were performed at various times postoperatively (within 24 hours, 1 week, 1 month, 2 months, 3 months, 6 months, 9 months, and 1 year). MR protocols included a T2-, diffusion-weighted, and T1-weighted sequences with and without intravenous administration of gadolinium. On T1, the wafers change from their initial hypointense to an isointense appearance after a period during which they appear to be hypointense, with a hyperintense rim most prominent less than 1 month postoperatively. On T2 they change from a hypointense to an isointense appearance. Restricted diffusivity reshaping the silhouette of the wafer's surface at the rim of the resection cavity can be found as early as day 1 postoperatively; however, 1 month after implantation, they all show areas of restricted diffusion, which may remain up to 1 year. Contrast enhancement at the rim of the resection cavity can already be found at day 1 postoperatively, with a peak shortly after 1 month after surgery. These changes can easily be mistaken for an abscess and hamper the early differentiation between residual tumor tissue and normal postoperative changes. However, early changes in either appearance do not predict overall survival or the progression free interval.     

Carcinoma of the cervix: Value of dynamic magnetic resonance imaging in assessing early stromal invasion

Background The purpose of this study was to assess the accuracy of contrast-enhanced magnetic resonance imaging (dynamic MR imaging) in the evaluation of preinvasive and early invasive cancer of the cervix. Methods Twenty-nine women with untreated squamous cell carcinoma of the cervix with either no stromal invasion or early stromal invasion underwent pretreatment MR imaging and dynamic MR imaging within 4 weeks of surgical evaluation. The images were evaluated for tumor detection and compared with results of histologic examination of the surgical specimens. Results The lesions in 17 cases with histologically proven stromal invasion of 4 mm or greater were detected with dynamic MR imaging, whereas lesions in only 8 of these cases were detected with T2 imaging. In 9 cases with stromal invasion between 4.0 mm and 5.0 mm, lesions were represented as early phase focal enhancement on dynamic MR images, but not detected on T2-weighted images. In the 12 cases with less than 4 mm stromal invasion, no lesions were visualized on either T2-weighted images or dynamic MR images, except in 1 case of glandular involvement without stromal invasion that appeared as enhancement on early-phase dynamic MR imaging. Conclusion Dynamic MR imaging detected more lesions of early stromal invasion in pretreatment imaging for cervical cancer than nonenhanced MR imaging.     

Pelvic hemangiopericytoma: the role of diffusion weighted imaging in targeting the biopsy site and in monitoring the tumour response to radiotherapy

BACKGROUND: Despite advances in imaging, the accurate characterization of soft tissue tumours remains a challenging task. Furthermore, the interpretation of post treatment changes and evaluation of tumour response to therapy is another complicating issue regarding soft tissue tumour imaging. CASE REPORT.: Herein, a patient with a pelvic hemangiopericytoma, by whom different diagnostic imaging methods were used, is presented. CONCLUSIONS: Diffusion weighted imaging (DWI) might provid useful information in guiding biopsy and enabled monitoring of the radiation therapy results.     

Diagnostic imaging of ankle syndesmosis injuries: A general review

Literature on the various techniques for imaging injuries to the ankle syndesmosis to determine the most appropriate imaging modality for diagnosing syndesmosis ligament disruption and instability was reviewed using the following data sources: Pubmed, Google scholar, SportsDiscus, E‐journals and PLOSone. Search terms used were: syndesmosis paired with injury, imaging, radiology, X‐ray, stress X‐ray, arthrography, ultrasound, nuclear medicine scan, CT scan, MRI and arthroscopy. Articles were selected by reading abstracts and the full article if indicated. Further articles were derived from the references of the primary articles. Plain x‐rays of the ankle will detect approximately half on AP view to two‐thirds on mortise view of syndesmosis injuries. Syndesmosis injuries frequently occur in association with tibial or fibular fractures. Intra‐operative stress radiography failed to detect approximately half of instabilities confirmed at arthroscopy. The current benchmark imaging techniques to diagnose syndesmosis injury and diastasis are arthroscopy and high‐power (3T) MRI. Ultrasound is a promising, developing, cost‐effective imaging technique which is yet to reach its full diagnostic potential. CT and nuclear medicine scans have limited roles. MRI (3T) scanning in the plane of the syndesmotic ligaments is the investigation of choice to detect ankle syndesmosis injuries. In the presence of associated injuries requiring surgery, arthroscopic viewing with stress examination is the diagnostic benchmark when available.     

Retroperitoneal sarcomas: A review of disease spectrum,radiological features,characterisation and management

Retroperitoneal sarcomas are a rare disease. The overall 5‐year survival rate for these lesions remains low, and surgical management offers the only option for effective treatment and potential for cure. Radiotherapy is increasingly being employed in addition to standard surgical treatment. Improvements in cross‐sectional imaging have also facilitated better characterisation of lesions, preoperative planning and long‐term follow‐up. This article reviews the current literature and documents the various types of retroperitoneal sarcomas with a particular approach to their imaging features. We also highlight the pathology, diagnostic methods and most current management of these tumours.     

CT强化与MR显像检测骨转移瘤的对比分析

目的:探讨CT强化与MR显像检测骨转移瘤的效果。方法:选择2009年5月至2013年1月在我院就诊的恶性肿瘤患者 110例,都进行骨骼部位的CT强化与MR显像检查,以病理结果为金标准判断诊断效果。结果:MR检查的骨转移瘤病灶数目明显高于CT强化检查(P<0.05)。脊柱与下肢带骨病变区的ADC值都明显高于邻近正常骨质,差异具有统计学意义(P<0.05)。CT诊断骨转移瘤的敏感度为71.7%,特异度为66.7%;而MR诊断骨转移瘤的敏感度为86.9%,特异度为66.7%。结论:相对于CT强化,MR显像可以早期诊断骨转移瘤,而结合ADC值定量测量,有利于病变的诊断。     

Ectopic expression of neutrophil gelatinase-associated lipocalin suppresses the invasion and liver metastasis of colon cancer cells

Neutrophil gelatinase-associated lipocalin (NGAL), also known as lipocalin 2, is a 25-kDa lipocalin initially purified from neutrophil granules. It is thought to play a role in regulating cellular growth since its expression is highly upregulated in a variety of proliferative cells such as cancer cells. However, experimental evidence showing a clear causal relationship between NGAL expression and the proliferation of tumor cells is lacking. Here, we found NGAL expression in highly and poorly metastatic colon cancer cell lines of the same genetic origin correlated inversely with the metastatic potential of these cells, which suggests NGAL participates in the metastatic process. To explore the role NGAL plays in tumor growth and metastasis, the KM12SM human colon cancer cell line, which is highly metastatic while showing decreased NGAL expression, was genetically manipulated to overexpress NGAL. The effects of this on tumor growth and liver metastasis were then analyzed using experimental animal models established by injecting BALB/c nude mice with tumor cells subcutaneously or intrasplenically. Ectopic expression of NGAL in the colon cancer cells had little effect on the growth and viability of the tumor cells both in vitro and in vivo. However, NGAL expression not only suppressed the ability of the colon carcinoma cells to invade Matrigel in vitro, it also substantially inhibited liver metastasis in an experimental animal model. Collectively, these results indicate that NGAL may be a candidate metastasis suppressor in colon cancer cells.     

肝泡型包虫病肝内外转移及其与肝癌的鉴别诊断

目的:探讨肝泡型包虫病肝内外转移及与肝癌的鉴别诊断。方法:分析经手术病理证实的20例肝泡型包虫合并肝内外转移患者的影像学资料,并行卡松尼试验及实验室检查。结果:20例病例中,脑转移3例,肺转移4例,脑转移合并肺转移3例,行相关影像学检查可见肝内、颅脑、肺实性占位性病变,以上病例行卡松尼皮内过敏试验均为阳性,AFP、CEA、CA199值均在正常范围内。结论:肝泡型包虫病类似肝恶性肿瘤,可从肝脏转移或扩张至其他器官,行相关影像学检查、卡松尼皮内过敏试验、AFP、CEA、CA199测定可与肝脏原发肿瘤相鉴别。     

Imaging neuroendocrine tumors: Characterizing the spectrum of radiographic findings

Neuroendocrine tumors (NET) are a group of neoplasms with neuroendocrine differentiation affecting a wide range of organs. Functional NETs present with symptoms due to the particular hormone produced. Functional NETs are usually small at diagnosis and therefore can be challenging to diagnose. In contrast, non-functioning NETs are generally larger and present with mass effect. Imaging plays an indispensable role in diagnosis, staging and management of patients with NETs. The optimal modality and technique for imaging of NETs depend on the location of primary and metastatic lesions. Regardless of the imaging modality, dynamic contrast-enhanced imaging is essential for evaluation of NETs. In general, CT scan is typically the primary imaging modality for evaluating NETs. MRI is used as a complementary modality, being superior to other modalities to assess liver metastasis. Nuclear medicine imaging is also widely used in NET assessment.     

Association between nonalcoholic fatty liver disease and colorectal adenoma: a systemic review and meta-analysis

Background

Nonalcoholic fatty liver disease (NAFLD) is considered to be a hepatic manifestation of metabolic syndrome (MetS) and the most common chronic liver disease worldwide. The association between NAFLD and colorectal adenoma has been investigated in multiples studies but the results have been conflicting. We performed a systematic review and meta-analysis to evaluate this in asymptomatic patients who underwent screening colonoscopy.

Methods

We searched the literatures of all languages from PubMed, EMBASE and the Cochrane library from January 1, 1980 through July 15, 2014. Combined and subgroup analyses stratified by study designs, study locations, characteristics of adenoma (location, size, number, and advanced adenoma) were performed.

Results

Four cross-sectional and one cohort studies with a total of 6,263 subjects were included in the meta-analysis. NAFLD was significantly associated with colorectal adenoma [pooled odds ratio (OR) 1.74, 95% confidence interval (CI): 1.53-1.97]. The association was more significant in Asian population (pooled OR =1.77, 95% CI: 1.52-2.05, n=3 studies), compared to European/North American population (pooled OR =1.42, 95% CI: 0.75-2.67, n=2 studies). NAFLD was significantly associated with the number of colorectal adenoma (pooled OR =1.78, 95% CI: 1.10-2.86, n=2 studies), but not the location, size, or presence of advanced adenoma.

Conclusions

Our results suggest NAFLD is significantly associated with the presence of colorectal adenoma in asymptomatic patients undergoing screening colonoscopy. This finding provides additional risk stratifications for applying colorectal cancer (CRC) screening strategies. However, more studies of western population are needed to further investigate the ethnic disparity.     

Preoperative assessment of myometrial and cervical invasion in endometrial carcinoma: Comparison of multi-section dynamic MR imaging using a three dimensional FLASH technique and T2-weighted MR imaging

Introduction: We aimed to show the diagnostic performance of magnetic resonance imaging by comparing T2-weighted images and dynamic 3D MR images in the assessment of myometrial and cervical invasion by endometrial carcinoma. Methods: This prospective study included 53 women consecutively diagnosed with endometrial carcinoma. The subjects were evaluated by TSE T2-weighted images and 3D FLASH-VIBE dynamic MR images by two radiologists with a special training in gynecology. Sensitivity, specificity, negative and positive predictive values were calculated for each imaging modality with regard to assessment of myometrial and cervical invasion. Results: The diagnostic accuracy of TSE T2-weighted and dynamic 3D FLASH-VIBE MR imaging for the identification of any myometrial invasion were estimated as 64% and 84%, respectively. In the differentiation of deep myometrial invasion from the superficial invasion, the diagnostic accuracy of TSE T2-weighted and dynamic 3D FLASH-VIBE MR images were 75.5%, and 88.7%, respectively. Additionally, in the determining of deep myometrial invasion the sensitivity, the specifity, PPV, and NPV were 76%, 75%, 50%, and 90.9% on T2-weighted images, respectively; 100%, 85%, 68.4%, and 100% on dynamic 3D MR images, respectively. The diagnostic accuracy of TSE T2-weighted and dynamic 3D FLASH-VIBE MR images for cervical invasion by endometrial carcinoma were 86%, and 92%, respectively. Conclusion: The multiplanar capabilities of MRI are invaluable to evaluate spreading and margins of an endometrial mass, and the 3D dynamic MR techniques offer the advantages of increased coverage and high spatial resolution. Three dimensional dynamic MR imaging may be recommended in the especially postmenouposal cases before performing potentially curative treatments.     

CT evaluation of congenital choanal atresia: Our experience and review of the literature

Congenital choanal atresia (CCA) is the developmental failure of the nasal cavity to communicate with the nasopharynx. The aim of this study was to investigate and analyse the CT findings in such cases. Seven patients with CCA were included in our study over a 3‐year period (2001–2004). All had a CT scan of the nasal cavity and nasopharynx to establish the diagnosis and to define the extent and type of atresia. The choanal atresia was found to be more commonly bilateral and more of the mixed (membranous–osseous) type. Bilateral CCA in the neonate is a medical emergency that should be treated as early as possible. Computed tomography is a valuable and easily accessible diagnostic tool.