Primary orbital hydatid cyst: computed tomography and magnetic resonance imaging findings

Orbital hydatid cyst is a rare form of hydatidosis, comprising less than 1% of all hydatid cysts reported. The first choice of treatment for orbital hydatid cyst is surgery. Preoperative diagnosis is important, so as to avoid rupture of the cyst and prevent the spread of the parasitic disease. Herein, we present the computed tomography and magnetic resonance imaging findings of a case of primary orbital hydatid cyst.     

Cardiovascular magnetic resonance imaging findings in children with myocarditis

Background Myocarditis is a common,potentially life-threatening disease that presents a wide rang of symptoms in children,as an important underlying etiology of other myocardial diseases such as dilated and arrhythmogenic right ventricular cardiomyopathy.The incidence of nonfatal myocarditis is probably greater than that of the one actually diagnosed,which is the result of the challenges of establishing the diagnosis in standard clinical settings.Currently,no single clinical or imaging finding confirms the diagnosis of myocarditis with absolute certainty.Historically,clinical exam,electrocardiogram （ECG）,serology and echocardiography had an unsatisfactory diagnostic accuracy in myocarditis.Endomyocardial biopsy remains as a widely accepted standard,but may not be suitable for every patient,especially for those with less severe disease.Our aim was to find the changes in cardiovascular magnetic resonance （CMR） imaging of children with myocarditis diagnosed by clinical criteria.Methods We studied 25 children （18 male,7 female; aged from 5-17 years） with diagnosed myocarditis by clinical criteria.CMR included function analyses,T2-weighted imaging,T1-weighted imaging before and after i.v.gadolinium injection （early gadolinium enhancement （EGE） and late gadolinium enhancement （LGE））.Results The T2 ratio was elevated in 21 children （84％,11 in anterolateral （44％）,5 in inferolateral （20％）,and 5 in septum （20％））,EGE was present in 9 children （36％,3 in anterolateral （12％）,4 in inferolateral （20％）,and 2 in septum （8％））,and LGE was present in 5 children （20％,2 in anterolateral （8％）,1 in inferolateral （4％）,1 in septum （4％）,and 1 in midwall of left ventricular （LV） wall）.In 9 children （36％）,two （or more） out of three sequences （T2,EGE,LGE） were abnormal.Conclusions The CMR findings in children with clinically diagnosed myocarditis vary within the groups,including regional or global myocardial signal increase in T2-w     

胎儿胸腔异常心脏位置的产前磁共振成像诊断

目的探讨产前磁共振成像(MRI)在胎儿胸腔异常心脏位置诊断中的应用价值。方法 57例孕妇,孕龄20～36周。产前常规行超声检查后24～48 h内行MRI检查,采用二维快速平衡稳态采集(2D FIESTA)序列、单次激发快速自旋回波(SSFSE)序列、快速反转恢复运动抑制(FIRM)序列以及动态FIESTA序列,行胎儿颅脑、胸部腹部常规及胸部(肺、心脏)重点冠状面、矢状面及横断面扫描,将产前MRI、超声表现与出生后影像表现或手术(n=49)、引产后尸体解剖结果(n=8)对照。结果原发性心脏位置异常即右位心5例;继发性心脏位置异常52例,其中右肺发育不良7例、先天性膈疝(CDH)18例、先天性肺囊腺瘤样畸形(CCAM)24例、支气管肺隔离症(BPS)2例和纵隔占位1例。结论 MRI各序列综合应用在胎儿胸腔异常心脏位置及病因诊断方面具有一定的应用价值;FIESTA序列同一切面能同时显示异常心脏位置和导致其异常的胸部其他病变,动态FIESTA序列能动态显示较明显的心脏血流异常;SSFSE和FIRM序列能较好显示引起心脏位置异常的其他胸部病变。     

视神经脊髓炎患者41例视神经磁共振分析

目的:探讨视神经脊髓炎(neuromyelitis optica,NMO)患者视神经的MRI表现特点。方法:对临床疑似NMO患者进行视神经、脑部和脊髓扫描,将满足NMO最新Wingerchuk诊断标准的41例患者纳为研究对象,进行随访研究,分析不同病程阶段视神经MRI表现特点,并与32位健康志愿者进行对照。同时,回顾性分析患者视神经诱发电位(visual evoked potential,VEP)检查结果,探讨MRI表现与VEP之间的关系。结果:正常志愿者MRI显示双侧视神经走行笔直,部分节段视神经鞘膜腔表现为稍高信号,但“双轨样”改变不明显。而NMO患者最常见的异常改变为视神经鞘膜腔信号显著增高,呈全程连续性“双轨样”改变,较健康志愿者明显不同。急性期,22例患者(53.7%)伴有视神经增粗或(和)扭曲; 17例(41.5%)可见视神经内点状高信号表现;31例(75.6%)在横断位T1WI上可见到视神经强化。缓解期,15例(36.6%)MRI上可见单侧或双侧视神经萎缩、变细和(或)扭曲。在本组研究结束时,共35例(80.5%)视神经内见点状高信号表现。对照VEP检查结果,MRI在反映视神经脱髓鞘改变上,敏感性为94.6%,但在急性期仅为43.6%,说明MRI检查具有一定的时间依赖性,不及VEP敏感。 结论:MRI能清晰显示NMO患者各个病理阶段视神经的形态改变,MRI可以成为视神经的首选影像学检查方法。     

韧带样型纤维瘤病CT、MRI表现与病理对照分析

目的 探讨韧带样型纤维瘤病的CT、MRI表现,提高CT、MRI对该病的认识和诊断水平.方法 回顾性分析经临床手术病理证实18例韧带样型纤维瘤病的临床、病理、CT、MRI特征.18例中10例行CT平扫、增强扫描,8例行MRI平扫及增强扫描,分析其CT、MRI表现特征并与病理结果对照.结果 腹部外病例发生于头颈部3例,胸背部2例,腹壁、腹股沟9例,腹腔内4例,1例与Gardner综合征伴发.本组中4例发生在腹部手术后1至3年内发病.韧带样型纤维瘤病病理:病变质地较硬.由梭形纤维母细胞和肌纤维母细胞组成.细胞无异型性,核分裂少见或无.局部呈侵袭性生长,有局部复发倾向但不发生远处转移.免疫组化:纤维母细胞和肌纤维母细胞都强表达波形蛋白Vimentin,肌纤维母细胞不同程度表达平滑肌肌动蛋白SMA.CT、MRI表现:良性,但呈现恶性肿瘤生长方式;可推挤周围脏器、血管,或包绕血管;边界多不清,呈浸润性生长,无包膜;坏死或钙化少见;密度、信号特点:均匀.强化方式:12例三期均明显均匀强化;5例不均匀强化.结论 韧带样型纤维瘤病具有特征性CT、MRI表现,CT、MRI对韧带样型纤维瘤病的诊断及鉴别诊断具有重要价值.     

胎儿结节性硬化症的超声与磁共振成像影像特征

目的 探讨胎儿结节性硬化症的产前超声检查及磁共振成像的影像特征。方法 选取2015年1月至2020年3月我院产前超声检出胎儿心脏肿瘤、颅内结节的病例作为研究对象,观察胎儿心脏肿瘤的部位、大小、数量、回声特征,结合磁共振检查及基因检测结果进行特征性分析。结果 在183 736例胎儿心脏产前超声筛查中,发现心脏肿瘤69例,发生率为0.38‰(69/183 736),肿瘤表现为类圆形实性高回声结节,部位分别位于心室、心房、室间隔、流出道内。69例心脏肿瘤胎儿中,30例行胎儿颅脑MRI检查,阳性17例,阴性13例;7例行TSC基因位点检测,阳性6例,阴性1例;13例行胎儿心脏超声随诊,肿瘤增大12例(伴增多4例),肿瘤大小及数量不变1例;临床最终确诊TSC共20例,发生率为0.11‰(20/183 736)。结论 胎儿心脏肿瘤的大小、数量随孕龄增大而发生变化,肿瘤体积越大、数量越多,最终诊断结节性硬化症的可能性越大,预后越差。产前超声随诊观察心脏横纹肌瘤的影像特征,结合磁共振检查及基因检测,能为临床及时诊断结节性硬化症提供帮助。     

Primary cardiac fibroma in an infant: Computed tomography and magnetic resonance imaging findings

Cardiac fibromas (CFs) are benign primary tumors that typically occur during childhood and may be asymptomatic. However, due to the proximity of CFs to the cardiac structure, significant morbidity and mortality may also be anticipated. CFs do not show spontaneous regression and surgical resection generally remains the treatment of choice for these tumors in children. Thus, it is important to take aggressive steps to obtain accurate pretreatment image diagnosis. A full-term male infant was presented to our facility suffering from shortness of breath, after an episode of upper respiratory tract infection at age 1.5 months. Subsequent chest X-ray revealed widening of the mediastinum and trachea deviation. Cardiogenic pathology was suspected. Computed tomography and magnetic resonance imaging were performed, and we confirmed a diagnosis of benign CF. Thoracotomy biopsy of the tumor confirmed the pathological diagnosis.     

Dysembryoplastic neuroepithelial tumors: magnetic resonance imaging and magnetic resonance spectroscopy evaluation

Background Dysembryoplastic neuroepithelial tumor （DNT） is a rare benign neoplasm of the central nervous system affecting young people. A correct preoperative diagnosis is helpful for planning surgical strategies and improving prognosis. The purpose of this study was to characterize DNTs using magnetic resonance imaging （MRI） and magnetic resonance spectroscopy （MRS） and to analyze the value of these two techniques in the diagnosis of DNTs. Methods MR images of 13 patients with DNTs were reviewed retrospectively; and five of the patients also underwent MRS. Tumors were confirmed by surgery. The distribution, extension and signal features of the lesions were assessed, and the MRS results were analyzed. Results All tumors were supratentorial. The cortex was the main area involved, with nine tumors located in the temporal lobe, three in the frontal lobe, and one on the boundary between the temporal and occipital lobes. All cases had decreased signal intensity on Tl-weighted MR images and increased signal intensity on T2-weighted images. On fluid attenuated inversion recovery weighted images, the hyperintense ＂ring sign＂ and internal septation of the lesion were seen in 9 cases. Eight tumors had well-demarcated borders. Peritumoral edema or mass effect was absent in all cases. A contrast enhancement examination was performed in 9 cases. Contrast enhancement was absent in five cases, and four cases showed significant enhancement. The MRS showed a low N-acetylaspartate peak and a lack of elevated choline-containing component （Cho） or Cho-Cr ratio （Cho/Cr） in five patients. Conclusions The MRI findings of DNTs were stereotypical. The combination of MRI and MRS techniques were helpful in making a correct presurgical diagnosis.     

西藏小型猪缺氧缺血性脑病模型的建立及病理和影像学表现

目的建立西藏小型猪缺氧缺血性脑病（HIE）模型,观察HIE模型MR表现并与病理结果对照。方法1~3 d龄西藏小型猪 6只（模型组4只,对照组2只）。模型组夹闭双侧颈总动脉放入缺氧箱内（氧浓度为8%）,60 min后,复氧及再灌注。对照组仅进 行双侧颈总动脉分离。模型组于模型建立后2 h、24 h、3 d、5 d进行脑部ESWAN检查。对照组于手术后2 h进行脑部增强T2*加 权的血管成像（enhanced T2 star weighted angiography, ESWAN）检查。常规MR检查采用SE序列T2FLAIR、T2WI及DWI,于模 型建立后24 h进行。最后进行病理学检查。结果新纹状体区T2*值于模型建立后3 d达峰值,不同时间点与对照组T2*值差异有 统计学意义（P<0.05）。皮层下白质区T2*值于模型建立后24 h达峰值（P<0.05）。新纹状体区R2*值于模型建立后3 d达最低值, 不同时间点与对照组差异有统计学意义（P<0.05）,皮层下白质区R2*值于模型建立后24 h达最低值（P<0.05）。Magnitude值于 模型建立后明显升高（P<0.05）。模型组动物脑部MR的DWI 成像可见双侧额部皮层下白质及双侧新纹状体略高信号, T2FLAIR信号变化不显著,T2WI未见明显异常。SWI可见粗大髓静脉及微出血。HIE早期病理变化以水肿及静脉淤血为主,偶 见局灶性坏死及含铁血黄素沉积。结论ESWAN序列可以评价HIE是否有出血及脑组织水肿。T2*值、R2*值、幅度值可用于观 察缺氧缺血性脑损伤的发生发展变化。     

Breast magnetic resonance imaging in patients with occult breast carcinoma: evaluation on feasibility and correlation with histopathological findings

Background  As an uncommon presentation, occult primary breast cancer remains a diagnostic and therapeutic challenge in clinical practice. This study aimed to retrospectively assess the feasibility of breast magnetic resonance imaging (MRI) in patients with malignant axillary lymphadenopathy and unknown primary malignancy, and correlation with histopathological characteristics.

Methods  A total of 35 women with occult breast carcinoma were evaluated with dynamic contrast-enhanced breast MRI. Whole seriate section was used in all cases. MRI performance was assessed and correlated with histopathological findings.

Results  Twenty-one of 35 patients were found to have primary breast carcinoma histologically. Twenty of the 21 patients had abnormal MR findings and 1 patient had a normal MRI study. Of the remaining 14 patients, 10 were negative on both MRI and surgery. Four had suspicious enhancement on MRI and no corresponding tumor was found. Lesions with mass enhancement were found in 55% (11/20) and ductual and segmental enhancement in 45%. The average diameter of the primary tumors was 15 mm. Invasive ductal carcinomas were found in 81% (17/21). One of 17 invasive ductual carcinomas was too small to be graded. Fourteen of the remaining 16 were classified as grade II and 2 as grade I. Thirty-two of the 35 patients had received estrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 examinations and the 12 of 32 were triple-negative breast carcinoma.

Conclusions  Mass lesions with small size and lesions with ductal or segment enhancement are common MRI features in patients with occult breast cancer. The dominant types of primary tumors are invasive ductal carcinoma with moderate histopathological grade. The rate of triple-negative breast carcinoma may be higher in occult breast cancer.

     

Assessment of the usefulness of magnetic resonance brain imaging in patients presenting with acute seizures

Background

Magnetic Resonance Imaging (MRI) is increasingly available as a tool for assessment of patients presenting to acute services with seizures.

Aims

We set out to prospectively determine the usefulness of early MRI brain in a cohort of patients presenting with acute seizures.

Methods

We examined the MR imaging studies performed in patients admitted solely because of acute seizures to Cork University Hospital over a 12-month period. The main aim of the study was to determine if the MRI established the proximate cause for the patient’s recent seizure. We identified 91 patients who underwent MRI brain within 48 h of admission for seizures.

Results

Of the 91 studies, 51 were normal (56 %). The remaining 40 studies were abnormal as follows: microvascular disease (usually moderate/severe) (n = 19), post-traumatic gliosis (n = 7), remote symptomatic lesion (n = 6), primary brain tumour (n = 5), venous sinus thrombosis (n = 3), developmental lesion (n = 3), post-surgical gliosis (n = 3) and single cases of demyelination, unilateral hippocampal sclerosis, lobar haemorrhage and metastatic malignant melanoma. Abnormalities in diffusion-weighted sequences that were attributable to prolonged ictal activity were seen in nine patients, all of who had significant ongoing clinical deficits, most commonly delirium. Of the 40 patients with abnormal MRI studies, seven patients had unremarkable CT brain. MR brain imaging revealed the underlying cause for acute seizures in 44 % of patients. CT brain imaging failed to detect the cause of the acute seizures in 19 % of patients in whom subsequent MRI established the cause.

Conclusion

This study emphasises the importance of obtaining optimal imaging in people admitted with acute seizures.     

Cartilage injury and repair: assessment with magnetic resonance imaging

Articular cartilage damage plays a major role in joint degeneration and dysfunction. Accurate assessment of the morphology and degree of cartilage wear is important in diagnosis, prognosis and management, particularly as many of these patients are young or participate in high-performance sports. Magnetic resonance imaging is able to directly evaluate such injuries, due to its high spatial resolution and excellent soft-tissue contrast resolution. This pictoral essay aims to demonstrate normal and damaged articular cartilage on MR imaging, as well as surgically-repaired cartilage.     

产前超声检查和磁共振成像对胎盘植入诊断的准确性评估

目的 探讨产前超声检查和磁共振成像对胎盘植入的诊断价值。方法 对于2010年11月至2014 年11月间在首都医科大学附属北京妇产医院产前检查过程中曾因可疑胎盘植入同时进行超声检查以及磁共振成像检查的76例病例进行回顾性分析。产后病理检查以明确诊断,评价两种检查方法产前对胎盘植入的诊断价值。结果 76例患者中,术后病理诊断确诊为胎盘植入的共45例;超声诊断的胎盘植入45例,其中3例术后排除胎盘植入,漏诊3例;磁共振成像诊断的胎盘植入46例,其中3例术后排除胎盘植入,漏诊2例。两种检查方法的敏感度、特异度、精确比、诊断指数等方面比较差异无统计学意义(P>0.05);Kappa值分别为0.835和0.863(>0.4)。结论 超声作为一项产前检查的常规项目,其对于胎盘植入的诊断价值是值得肯定的;彩超和磁共振检查作为产前诊断胎盘植入的主要手段,其诊断价值值得肯定;当超声结果为阴性或胎盘附着于子宫后壁时,磁共振成像可作为重要的补充检查方法。     

超声检查联合磁共振成像对前置胎盘合并胎盘植入的诊断价值

目的 探讨超声检查联合磁共振成像对前置胎盘并胎盘植入的诊断价值.方法 选取2018年1月至2020年12月我院收治的64例怀疑前置胎盘并胎盘植入患者进行回顾性分析,患者均行超声检查与磁共振成像,将剖宫产手术和病理结果作为金标准,评价超声检查、磁共振成像以及二者联合对前置胎盘并胎盘植入的诊断价值.结果 64例患者中,诊断...     

Incidental findings on brain magnetic resonance imaging from 1000 asymptomatic volunteers.

CONTEXT: Previous reports have discussed incidental disease found on brain magnetic resonance imaging (MRI) scans that had been requested for an unrelated clinical concern or symptom, resulting in a selection bias for disease. However, the prevalence of unexpected abnormalities has not been studied in a healthy population. OBJECTIVE: To evaluate the prevalence of incidental findings on brain MRI scans obtained for a healthy, asymptomatic population without selection bias. DESIGN, SETTING, AND PARTICIPANTS: Retrospective analysis of brain MRI scans obtained between May 17, 1996, and July 25, 1997, from 1000 volunteers who participated as control subjects for various research protocols at the National Institutes of Health. All participants (age range, 3-83 years; 54.6% male) were determined to be healthy and asymptomatic by physician examination and participant history. MAIN OUTCOME MEASURE: Prevalence of abnormalities on brain MRI by category of finding (no referral necessary, routine referral, urgent referral [within 1 week of study], and immediate referral [within 1 to several days of study]). RESULTS: Eighty-two percent of the MRI results were normal. Of the 18% demonstrating incidental abnormal findings, 15.1% required no referral; 1.8%, routine referral; 1.1%, urgent referral; and 0%, immediate referral. In subjects grouped for urgent referral, 2 confirmed primary brain tumors (and a possible but unconfirmed third) were found, demonstrating a prevalence of at least 0.2%. CONCLUSION: Asymptomatic subjects present with a variety of abnormalities, providing valuable information on disease prevalence in a presumed healthy population. A small percentage of these findings require urgent medical attention and/or additional studies.     

Differentiation of white and red thrombus with magnetic resonance imaging: a phantom study

Background  An early identification of the composition of arterial thrombus may have diagnostic, therapeutic, and prognostic implications. The variation of magnetic resonance (MR) signal intensity between white and red thrombi, especially in the susceptibility sensitive MR sequence, remains unknown. Our research was to evaluate the feasibility of MRI in differentiating of white and red thrombi with a phantom study.

Methods  A total of 12 red and 12 white thrombi were prepared with the venous blood. Examination of the phantom was completed using a 3.0T MR unit, including fluid attenuated inversion recovery (FLAIR) T1, T2-weighted imaging (T2WI), FLAIR T2, T2* gradient echo (T2*GRE) imaging, and susceptibility weighted angiography sequences (SWAN). MR signal intensity patterns of the thrombi were objectively classified as hyperintensity, isointensity and hypointensity, compared with the background agar. The volume of thrombus was calculated and correlated with its signal intensity.

Results  For white thrombi, 11/12 clots showed hyperintensity and 1/12 showed isointensity in FLAIR T1 images. In T2WI, 6/12 clots showed hyperintensity, 3/12 isointensity, and 3/12 hypointensity. In FLAIR T2, 8/12 clots showed hyperintensity and 4/12 showed isointensity. In T2*GRE, 3/12 clots showed hyperintensity and the remaining 9/12 clots showed isointensity. In SWAN, 5/12 clots demonstrated hyperintensity and 7/12 isointensity. For the red thrombus, 12/12 clots demonstrated hyperintensity in FLAIR T1, T2WI, and FLAIR T2 sequences. In T2*GRE and SWAN sequences, 3/12 clots displayed hypointensity and the remaining 9/12 clots showed slight hyperintensity. Thrombi with hypointensity displayed in T2*GRE and SWAN sequences were significantly larger than those with hyperintensity.

Conclusions  Differentiation of white and red thrombi with conventional MR sequence is unreliable, because both kinds of thrombi do not possess unique signal intensity features in these sequences. Red thrombus may or may not show hypointensity in the susceptibility sensitive MR sequences, depending on its size and time course.

     

健康青年男性脑部磁共振成像的偶然发现

背景与目的：确定健康青年男性人群中严重颅内异常的发生率。方法：对2536例健康男性青年受试者进行头部MRI检查，受试者的平均年龄为20．5岁，均在德国空军从事军事飞行工作。结果：本文对该大样本健康青年男性人群中的多种脑部形态异常进行报道，并提供脑部异常患病率方面的资料。其中，1．7％（95％CI1．2％-2．3％）的受试者发生蛛网膜囊肿、0．51％（95％CIO．29％-0．9％）的受试者发生血管异常以及0．47％（95％CI0．26％-0．85％）的受试者发生脑内肿瘤，无脑动脉瘤发生。结论：与预期相比，原发性脑肿瘤的患病率较高，而脑内动脉瘤的患病率则较低。并且，只有一小部分发现脑部异常的受试者需要立即采取医疗干预措施。     

Characteristic findings of malignant melanoma in the sinonasal cavity on magnetic resonance imaging

Background  Malignant sinonasal melanoma (MSM) is a rare tumor with a perplexing signal intensity due to variable histopathologic components. This study was undertaken to delineate its MR imaging features.

Methods  MR imaging findings of 10 patients (6 women and 4 men, mean age 61.3 years old) with pathologically confirmed MSM were retrospectively reviewed. The location, size, signal intensity, enhancement, and internal imaging characteristics of all tumors were evaluated. Signal intensity and degree of enhancement was graded in comparison with the gray matter and adjacent muscle uptake, respectively.

Results  There were 8 tumors that were pathologically confirmed to contain melanin. Compared to gray matter of the brain, 7 of them demonstrated hyperintensity on T1WI and 6 (6/7) showed hypointensity on T2WI. There was multiple linear, dark-signal intensity on T2WI within the mass in 9 of the 10 patients’ tumors. Evaluated with gadolinium-enhanced imaging, all 10 patients showed moderate enhancement within the areas that were isointense in the lesion on pregadolinium T1WI. Moreover, some parts which displayed hyperintensity on T1WI within the tumors of 7 patients showed mild enhancement that was similar to muscle on a time-intensity curve (TIC).

Conclusions  MSM shows characteristic MR signal intensity (hyperintensity on T1WI and the linear, low-signal intensity on T2WI), which may provide valuable information for clinical diagnosis. Together with conventional MRI, TIC may be useful for indicating pleomorphic patterns of MSM.