Hepatocellular Carcinoma: MR Imaging

Thirty patients with hepatocellular carcinoma (HCC) were examined by MRI. Distinctive findings of HCC such as the presence of fatty degeneration, a capsule, mosaic pattern, daughter nodules and tumor thrombi in major veins were noted in 6, 13, 1, 10 and 9 cases or 20%, 43%, 3%, 33% and 30% respectively.     

胆管癌的磁共振成像表现及其临床意义

目的：通过磁共振成像(MR)征象与手术对照分析，探讨胆管癌的MR特点。方法：27例患行常规轴位SE，12加权成像和呼吸门控FSE，12加权成像，并做冠状位：MRCP成像，所有患经手术和病理证实，分析病灶信号特征、形态、范围，并与术中所见进行比较。结果：16例肝门型胆管癌在磁共振成像上多呈放射状(89％)，术中所见病灶沿胆管浸润生长，且病灶范围比MRI所见大。所有胆管癌病灶在TIWI上均呈低信号(100％)，4例肝内胆管癌在T2WI上为混杂信号，11例肝门型胆管癌在，T2WI上呈等(61％)或稍高信号(39％)，2例壶腹癌在T2WI上呈低信号。在MRCP上所有病人表现为胆道梗阻。16例(89％)：MRCP分型与临床分型一致。结论：胆管癌在磁共振成像上有较特征性表现，且能提供病变准确部位，但对病变范围估计不足，MRCP用于肝门型胆管癌临床分型是可行的。     

脊膜瘤磁共振诊断与病理相关性研究

目的：通过分析脊膜瘤的MRI表现特征、探讨其诊断价值及病理意义。方法：分析术前行MRI检查且经手术和病理检验证实的脊膜瘤患者28例、30个瘤灶,观察肿瘤增强前后的信号改变、瘤体形态及邻近脊膜改变,并进行术后病理检验对照。结果：脊膜瘤MRI特征性表现主要为T1WI等或稍低信号,T2WI等或稍低信号。瘤体内信号较均匀,增强扫描瘤灶呈均质中等强化,形态多为短棒状,可见“脊膜尾征”,病理切片对照显示“尾”实际上其内层是肿瘤组织的延续,外层是异常增厚的脊膜,两层之间无明显分界。结论：脊膜瘤的MRI表现具有较高的特征性,诊断价值极高,定位准确率达100％,定性准确率达93．3％,“脊膜尾征”的“尾”有肿瘤组织成分,且有重要的诊断意义,血管型脊膜瘤易被误诊为神经鞘瘤。     

A Short Illustrated History of Magnetic Resonance Imaging

The principles of Magnetic Resonance Imaging (MRI) evolved during the late 1970s and early years of the following decade. The author was fortunate in being able to visit many of the pioneer research projects in the U.K. and U.S.A. and attend two conferences. This paper briefly describes these projects and their role in the evolution of the present technology, illustrated by photographs obtained from colour slides taken during these visits.     

Cardiovascular Evaluation in Turner Syndrome: Utility of MR Imaging

Forty patients with karyotypidy proven Turner syndrome were prospectively studied using magnetic resonance imaging (MRI) and echocardiography in order to determine the frequency of cardiovascular anomalies and to assess the utility of both imaging modalities as methods for cardiovascular evaluation in Turner syndrome. Cardiovascular anomalies were found in 45% of patients A high absolute prevalence of bicuspid aortic valve (175%) and aortic coarctation (12.5%) were observed relative to comparable series. Of clinically significant abnormalities, three of five aortic coarctations and four of five ascending aortic dilatations were solely MRI detected and not evident at echocardiographic examination. MRI is thus seen as a valuable adjunct to echocardiography in the cardiovascular evaluation of Turner syndrome patients. The usefulness of MIU primarily relates to its ability to provide excellent visualisation of the entire thoracic aorta where a large proportion of clinically significant anomalies Occur in Turner syndrome.     

Ultrasonic Evaluation of Abdominal Aortic Aneurysm

The ultrasonic findings in 64 patients suspected of having an abdominal aortic aneurysm are described. 25 patients had aortic aneurysms, 16 of which were confirmed by aortography, surgery or autopsy. The ultrasonic diagnosis was accurate in 15 of the 16 (94%), and close correlation was found with measurement of size and assessment of the presence of mural thrombus. The procedure is a non-invasive and valuable one in the evaluation of abdominal aortic aneurysm.     

Geometrical confinement of Gd(DOTA) molecules within mesoporous silicon nanoconstructs for MR imaging of cancer

Porous silicon has been used for the delivery of therapeutic and imaging agents in several biomedical applications. Here, mesoporous silicon nanoconstructs (SiMPs) with a discoidal shape and a sub-micrometer size (1000 × 400 nm) have been conjugated with gadolinium-tetraazacyclododecane tetraacetic acid Gd(DOTA) molecules and proposed as contrast agents for Magnetic Resonance Imaging. The surface of the SiMPs with different porosities – small pore (SP: ∼5 nm) and huge pore (HP: ∼40 nm) – and of bulk, non-porous silica beads (1000 nm in diameter) have been modified with covalently attached (3-aminopropyl)triethoxysilane (APTES) groups, conjugated with DOTA molecules, and reacted with an aqueous solution of GdCl₃. The resulting Gd(DOTA) molecules confined within the small pores of the Gd-SiMPs achieve longitudinal relaxivities r₁ of ∼17 (mM s)⁻¹, which is 4 times greater than for free Gd(DOTA). This enhancement is ascribed to the confinement and stable chelation of Gd(DOTA) molecules within the SiMP mesoporous matrix. The resulting nanoconstructs possess no cytotoxicity and accumulate in ovarian tumors up to 2% of the injected dose per gram tissue, upon tail vein injection. All together this data suggests that Gd-SiMPs could be efficiently used for MR vascular imaging in cancer and other diseases.     

Magnetic Resonance Imaging in Occult Spinal Dysraphism

A prospective study was carried out in 100 cases of suspected occult spinal dysraphic anomalies with Magnetic Resonance Imaging in order to determine its diagnostic efficacy as the initial imaging modality. MR imaging provided accurate preoperative information in 91 out of 92 cases (98.9%). Some of the unusual and interesting findings in the series were: presence of intrinsic cord abnormality in 19 out of 21 cases (90.4%) with a normal plain radiograph, 4 cases of diastematomyelia with a dermoid in the dorsal and lumbar region associated with syringohydromyelia, intradural fibrous/glial bands, sgringo-hydromyelia/myelomalacia of the conus with tethered cord syndrome having a normally placed conus, and myelocystocele. It is concluded that MRI is an excellent primary diagnostic tool, together with a plain radiograph, for complete preoperative evaluation of mid-tine spinal anomalies.     

The Evaluation of Thoracic Paraspinal Neurogenic Tumours The Role of Magnetic Resonance Imaging

Paraspinal neurogenic tumours may have associated intraspinal tumour extension. It is important that such extension be accurately defined preoperatively in order that an appropriate surgical approach may be planned. It has been suggested in the literature that MRI (where available) should replace myelography and post myelographic CT in the preoperative evaluation of these patients. The literature is reviewed and the potential role of MRI is illustrated in three cases.     

量化 DCE-MRI 技术对乳腺良恶性病变诊断价值分析

目的：探讨基于动态增强磁共振成像（dynamic contrast-enhanced MRI,DCE-MRI）及特定药物动力学模型所获得的量化参数对乳腺良恶性病变诊断价值。方法：收集我院2015年6月至2016年2月42例乳腺病变患者行 DCE-MRI 扫描,通过后处理软件测量如下量化参数,定量参数：容量转移常数（volume transfer constant, Ktrans ）、速率常数（rate constant,Kep ）、血浆分数（the plasma fraction,Vp ）;半定量参数：（1）增强后病灶达峰时间（time to peak,TTP）、（2）增强后病灶内造影剂最大浓度值（max concentration,MAX Conc）、（3）增强后时间信号曲线下面积（area under curve,AUC）、（4）增强后时间信号曲线最大斜率值（MAX Slope）。检查后1周内均经手术取得病理诊断,采用独立样本 t 检验或非参数检验比较良性组及恶性组间各量化参数的差异。绘制 ROC 曲线,并分析有价值量化参数对乳腺良、恶性病灶诊断价值。结果：恶性病灶组定量参数 Ktrans Max（t ＝2．228,P ＝0．033）、Ktrans Mean（t ＝4．092,P ＜0．001）、Kep Mean（Z ＝2．422,P ＝0．015）、Kep Max（t ＝2．240,P ＝0．031）及半定量参数 MAX Conc Max（t ＝3．256,P ＝0．002）、MAX Conc Mean（t ＝3．460,P ＝0．001）、AUC Max（t ＝2．250,P ＝0．034）、AUC Mean（t ＝2．861,P ＝0．007）、MAX Slope Max（t ＝2．478,P ＝0．018）、MAX Slope Mean（t ＝2．226,P ＝0．032）较良性病灶组值明显升高,而半定量参数 TTP Min（t ＝－5．145,P ＜0．001）、TTP Mean（t ＝－3．818,P ＜0．001）较良性病灶组明显缩短。经 ROC 曲线分析显示,Ktrans Mean、Kep Mean、TTP Min、MAX Conc Max、AUC Mean、MAX Slope Max 对乳腺良恶性病变具有诊断价值,根据最大约登指数计算最佳诊断阈值,分别以0．1137、0．0258、0．9065、0．1059、0．1640、0.1502为诊断阈值,其鉴别诊断乳腺病灶良恶性敏感度分别为73．33％、73．33％、91．67％、76．67％、80．00％、80.00％,特异性分别为100％、83．30％、70．00％、91．70％、66．70％、75．00％。结论：基于 DCE-MRI 技术及特定的药物动力学模型所获得的量化参数对乳腺良恶性病变鉴别诊断有临床价值,且有较高的诊断效能,有望成为无创性评价乳腺肿瘤微循环的新方法。     

Magnetic Resonance Imaging in Herpes Simplex Encephalitis

Four patients with clinical and serologically proven Herpes Simplex Encephalitis (HSE) were examined by Magnetic Resonance Imaging (MRI) following Computed Tomographic (CT) scans. MRI proved more sensitive at detecting the temporal lobe abnormalities than CT and invariably showed the lesions to be more extensive than suspected. The findings were consistent with an acute inflammatory process. Haemorrhage was present in only one patient. The sharp transition to normal at the lentiform nucleus previously described on CT was present in only one of the four patients, but was observed in a different patient with cerebral lymphoma and no evidence of HSE and is thus concluded to be less specific than previously thought. A repeat MRI scan at seven months on one of the patients showed persisting increased signal on T2 weighted images after resolution of the mass effect. The pathology and suspected mechanisms for the MRI appearances are discussed. MRI is concluded to be a valuable tool in the early diagnosis of HSE and in the longer term for further evaluation of residual disabilities.     

Aortic Aneurysm Presenting as Budd Chiari Syndrome

Budd Chiari Syndrome is the eponymic designation of symptomatic post sinusoidal venous obstruction, whether or not this is associated with hepatic vein occlusion or vena caval obstruction. Dutta and associates (1) classified the syndrome into two distinct types. Type I involves obstruction to the hepatic veins while Type II pertains to an obstruction in the inferior vena cava above the entry of hepatic veins. We report a case of thoraco-abdominal aortic aneurysm presenting as Type II Budd Chiari Syndrome.     

Dynamic MR imaging for functional vascularization depends on tissue factor signaling in glioblastoma

Glomeruloid vascular proliferation (GVP) is a diagnostic hallmark and links to aggressive behavior, therapy resistance and poor prognosis in glioblastoma (GBM). It lacks clinical approaches to predict and monitor its formation and dynamic change. Yet the mechanism of GVPs also remains largely unknown. Using an in situ GBM xenograft mouse model, combined clinical MRI images of pre-surgery tumor and pathological investigation, we demonstrated that the inhibition of tissue factor (TF) decreased GVPs in Mouse GBM xenograft model. TF shRNA reduced microvascular area and diameter, other than bevacizumab. TF dominantly functions via PAR2/HB-EGF-dependent activation under hypoxia in endothelial cells (ECs), resulting in a reduction of GVPs and cancer cells invasion. TF expression strongly correlated to GVPs and microvascular area (MVA) in GBM specimens from 56 patients, which could be quantitatively evaluated in an advanced MRI images system in 33 GBM patients. This study presented an approach to assess GVPs that could be served as a MRI imaging biomarker in GBM and uncovered a molecular mechanism of GVPs.     

The CT Appearances of Ruptured Abdominal Aortic Aneurysms

There is no place for investigative CT scans in patients who have the classical triad of abdominal aortic aneurysm rupture, namely excruciating abdominal pain or backache, a pulsatile mass and hypotension. These patients require immediate surgery. However, in the absence of this triad, CT scans play an important role in the diagnosis of abdominal aortic aneurysm rupture. The CT scan findings will dictate whether the patient requires immediate surgery as in the case of acute rupture, or, whether the surgery can be delayed up to 24 hours to allow for stabilisation and hydration, as in the case of subacute and chronic rupture.     

脑星形细胞瘤MRI定量指标与PCNA表达的关系

目的探讨星形细胞瘤MRI定量指标与PCNA表达的关系.方法收集手术病理证实的脑星形细胞瘤32例,计算下列MRI定量指标:T1WI、T2WI上的相对信号强度(RSk)、增强后相对信号强度(RSIGd)及信号强度增加百分率(EP).采用免疫组化的方法标记PCNA,对照MRI定量参数与PCNA标记指数之间的关系.结果恶性组与偏良性组之间,上述MRI定量参数均有统计学差异;增强后相对信号强度(RSIGd)及信号强度增加百分率(EP)与PCNA呈正相关.结论增强后相对信号强度(RSOGd)及信号强度增加百分率(EP)可以较好地反应星形细胞瘤的PCNA表达强弱和病理级别.     

M.R.I. Spectrum of Intrinsic Spinal Cord Lesions

We report our experience of 42 patients undergoing magnetic resonance imaging (MRI) studies demonstrating intrinsic lesions of the spinal cord, excluding those secondary to spondylosis, trauma or congenital malformations. Histological confirmation of the radiological diagnosis was obtained in 15 (36%). MRI is more sensitive than either myelography or CT. MRI identified a previously non-visualised lesion in 17 of 30 cases. In a further 13 cases, MRI contributed by identifying associated features such as cysts and haemorrhage which have aided in the diagnosis and management of the patients. The last 12 cases, which were patients with multiple sclerosis, had MRI as the only neuroradiological examination. These illustrate a range of appearances. The overlap of imaging appearances of the various pathologies implies that a useful diagnosis and differential can only be offered by considering the MRI appearances of a lesion, with its associated features, with the clinical presentation, and with other imaging modalities where appropriate.     

Technical Radiotherapy Advances – The Role of Magnetic Resonance Imaging-Guided Radiation in the Delivery of Hypofractionation

Safe delivery of hypofractionated radiotherapy requires high levels of accuracy due to the high doses of radiation delivered per fraction. Magnetic resonance guided radiotherapy (MRgRT) represents a new treatment paradigm which allows improved visualisation of targets and organs at risk, alongside the capability to adapt the treatment plan in real time prior to treatment delivery. There are challenges to delivering hypofractionated radiotherapy with conventional image-guided radiotherapy (IGRT) techniques and MRgRT may help to improve accuracy in radiation delivery in a number of clinical and anatomical scenarios.Specifically, there is an emerging role of MRgRT in delivering stereotactic body radiotherapy (SBRT) for locally advanced pancreatic cancer (LAPC) due to the superior soft tissue contrast provided by Magnetic Resonance Imaging combined with the ability to accommodate variation in anatomical appearances during treatment delivery. Reported data on the use of MRgRT in LAPC and it's role in enabling dose escalation are discussed in this article.There are further potential benefits to the use of MRgRT, for example the use of functional imaging during treatment delivery and generation of synthetic computed tomography, which have previously been impractical or unachievable. The overall aim of this article is to demonstrate the utility of MRgRT in facilitating safe delivery of hypofractionated radiotherapy and to highlight ways in which it may help to overcome challenges posed by current IGRT techniques.     

The Predictive Value of Magnetic Resonance Imaging-based Texture Analysis in Evaluating Histopathological Grades of Breast Phyllodes Tumor

PurposeKnowing the distinction between benign and borderline/malignant phyllodes tumors (PTs) can help in the surgical treatment course. Herein, we investigated the value of magnetic resonance imaging-based texture analysis (MRI-TA) in differentiating between benign and borderline/malignant PTs.MethodsForty-three women with 44 histologically proven PTs underwent breast MRI before surgery and were classified into benign (n = 26) and borderline/malignant groups (n = 18 [15 borderline, 3 malignant]). Clinical and routine MRI parameters (CRMP) and MRI-TA were used to distinguish benign from borderline/malignant PT. In total, 298 texture parameters were extracted from fat-suppression (FS) T2-weighted, FS unenhanced T1-weighted, and FS first-enhanced T1-weighted sequences. To evaluate the diagnostic performance, receiver operating characteristic curve analysis was performed for the K-nearest neighbor classifier trained with significantly different parameters of CRMP, MRI sequence-based TA, and the combination strategy.ResultsCompared with benign PTs, borderline/malignant ones presented a higher local recurrence (p = 0.045); larger size (p < 0.001); different time-intensity curve pattern (p = 0.010); and higher frequency of strong lobulation (p = 0.024), septation enhancement (p = 0.048), cystic component (p = 0.023), and irregular cystic wall (p = 0.045). TA of FS T2-weighted images (0.86) showed a significantly higher area under the curve (AUC) than that of FS unenhanced T1-weighted (0.65, p = 0.010) or first-enhanced phase (0.72, p = 0.049) images. The texture parameters of FS T2-weighted sequences tended to have a higher AUC than CRMP (0.79, p = 0.404). Additionally, the combination strategy exhibited a similar AUC (0.89, p = 0.622) in comparison with the texture parameters of FS T2-weighted sequences.ConclusionMRI-TA demonstrated good predictive performance for breast PT pathological grading and could provide surgical planning guidance. Clinical data and routine MRI features were also valuable for grading PTs.     

Abdominal Aortic Aneurysm with Perianeurysmal Fibrosis: Demonstration of Ureteric Obstruction by Computerized Tomography

When perianeurysmal fibrosis occurs in association with an abdominal aortic aneurysm it may produce ureteric obstruction and renal function impairment. Such a case is described and the pre-operative radiological evaluation of this condition is discussed. The role of computerized tomography is emphasized in its ability to provide accurate anatomical detail regarding the aneurysm, the extent of surrounding fibrosis and ureteric involvement within it.     

腹主动脉旁淋巴结切除术在子宫内膜癌开腹手术治疗中的应用价值

目的 探讨腹主动脉旁淋巴结清扫在子宫内膜癌开腹手术治疗中的临床意义.方法 选择接受手术治疗并经病理确诊为子宫内膜癌的患者172例,根据术中是否进行腹主动脉旁淋巴结清扫将入选患者分为观察组109例和对照组63例.观察2组患者围手术期相关指标指标.随访3年,观察2组患者的生存、复发情况及并发症的情况.结果 观察组患者手术时间和住院时间长于对照组,差异有统计学意义(P<0.05).观察组和对照组患者的生存率和死亡率差异无统计学意义(P>0.05),观察组患者的复发率低于对照组(P<0.05),其中病理分级为G2和G3期的观察组患者术后复发率显著低于对照组(P<0.05).观察组患者术后发生淋巴囊肿、下肢淋巴水肿和肠梗阻的概率高于对照组,差异有统计学意义(P<0.05).结论 子宫内膜癌手术治疗中行腹主动脉旁淋巴结清扫能有效降低患者术后复发率,但是增加了术后淋巴囊肿和下肢淋巴水肿的发生率,临床推行过程中应充分评估患者的自身情况.