Leukoencephalopathy with swelling in children and adolescents: MRI patterns and differential diagnosis

In children, several neurological disorders are characterised by spongiform leukoencephalopathy. MRI of the brain typically shows white matter swelling, but does not enable differentiation of the various underlying disorders. The aim of this article is optimisation of the diagnostic value of MRI in leukoencephalopathy accompanied by swelling. MRI-based inclusion criteria were met by 20 patients in our database. The images were analysed using a detailed scoring list. In 13 of the 20 patients the clinical diagnosis was known (11 definite and 2 probable diagnoses). Characteristic MRI abnormalities could be defined in these patients. Of the 7 patients without a diagnosis, 5 had identical MRI abnormalities: difuse hemisphere swelling and typical cysts in frontoparietal subcortical white matter and the tips of the temporal lobes. The clinical picture was also similar in these patients, suggesting a similar disease.     

环孢霉素A致可逆性后部白质脑病综合征的MRI表现

目的探讨环孢霉素A诱发可逆性后部白质脑病综合征(PRLS)的MRI表现。资料与方法回顾性分析1例PRLS的临床资料和MRI表现并复习文献。结果MRI显示PRLS以顶枕叶为主的皮层及皮层下白质病变,病变多呈双侧对称性分布,偶可累及双侧颞叶后部及额叶,T2WI和液体衰减翻转恢复序列(FLAIR)对病变的显示有独特的作用,扩散加权成像(DWI)能够确定PRLS的临床分期。结论PRLS在MRI上具有特征性。MRI表现结合临床资料,对PRLS多能作出正确的诊断。     

MRI in paediatric hypoxic-ischemic disease, metabolic disorders and malformations-a review

MRI has become the most important modality in paediatric neuroimaging. It provides an excellent anatomical overview with good spatial and temporal resolution, allows investigations of the blood vessels, and - using technologies such as diffusion-weighted imaging and magnetic resonance spectroscopy - it allows quick and exact differentiation of ischemic, hypoxic, inflammatory, oncologic, traumatic and metabolic diseases. This review presents an overview of brain MRI in infants and children with suspected hypoxic-ischemic disease, metabolic disorders or (vascular) malformations, illustrating these issues by some MRI findings in selected important conditions and discussing some major clinical and pathophysiological aspects important for imaging.     

Magnetic resonance imaging of anterior temporal lobe cysts in children: discriminating special imaging features in a particular group of diseases

Introduction

We hypothesised that disorders with anterior temporal lobe (ATL) cysts might exhibit common peculiarities and distinguishable imaging features that could be useful for diagnosis. We reviewed a series of patients for neuroimaging contributions to specific diagnoses.

Methods

A literature search was conducted, and institutional imaging files were reviewed to identify MR examinations with ATL cysts in children. Patients were divided according to head size, calcifications, white matter and cortical abnormalities. Unsupervised hierarchical clustering of patients on the basis of their MR and CT items was performed.

Results

We identified 23 patients in our database in whom MR revealed ATL cysts. Our series included five patients with congenital muscular dystrophy (05/23?=?21.7 %), six with megalencephalic leukoencephalopathy with subcortical cysts (06/23?=?26.1 %), three with non-megalencephalic leukoencephalopathy with subcortical cysts (03/23?=?13.1 %), seven with congenital cytomegalovirus disease (07/23?=?30.4 %) and two with Aicardi–Goutières syndrome (02/23?=?8.7 %). After analysis, 11 clusters resulted in the highest discriminative indices. Thereafter, patients’ clusters were linked to their underlying diseases. The features that best discriminated between clusters included brainstem abnormalities, cerebral calcifications and some peculiar grey and white matter abnormalities. A flow chart was drafted to guide the radiologist in these diagnoses.

Conclusions

The authors encourage the combined interpretation of these features in the herein proposed approach that confidently predicted the final diagnosis in this particular group of disorders associated with ATL cysts.     

Megalencephalic leukoencephalopathy with subcortical cysts in an adult: quantitative proton MR spectroscopy and diffusion tensor MRI

A 37-year-old macrocephalic woman was investigated for increasing gait disturbance due to longstanding spasticity and ataxia. MRI showed widespread bilateral increase in signal from cerebral white matter on T2-weighted images. Numerous subcortical cysts were visible in anterior-temporal and parietal regions. These clinical and neuroradiological features are those of megalencephalic leukoencephalopathy with subcortical cysts (MLC), a recently delineated white-matter disease with onset in childhood. Quantitative localised proton MR spectroscopy of white matter revealed marked reduction of N-acetylaspartate, creatine, and choline with normal values for myo-inositol, consistent with axonal loss and astrocytic proliferation. Diffusion tensor imaging showed an increased apparent diffusion coefficient and reduced anisotropy in affected white matter pointing to reduced cell density with an increased extracellular space. These findings are in line with histological changes alterations known to occur in MLC.     

The spatial distribution of MR imaging abnormalities in cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy and their relationship to age and clinical features

BACKGROUND AND PURPOSE: Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a condition causing recurrent subcortical strokes. MR imaging, which shows focal lacunar infarcts and leukoaraiosis, plays a central role in the diagnosis and evaluation. We studied MR imaging abnormalities in a large prospectively recruited cohort of CADASIL patients to describe the spatial distribution of abnormalities, determine how this distribution alters with age, and identify any correlations with the clinical features of the disease. METHODS: In this study, 112 CADASIL subjects from 64 families were prospectively recruited. MR imaging scans were graded by a single neuroradiologist, by using the modified Scheltens scale, to quantify the severity of high-signal-intensity changes in different brain regions. RESULTS: Lesion load increased progressively with age. Scores were maximal in the frontal, parietal, and anterior temporal cortex, and the external capsule; intermediate in the pons; and relatively low in the corpus callosum, caudate, globus pallidus, cerebellum, midbrain, and medulla. Anterior temporal pole involvement was common at all ages and, when present, usually confluent, but this was absent in 33% of patients 20-29 years of age. A history of stroke correlated with total Scheltens score and internal capsule and pontine scores. Dementia correlated with total Scheltens score and subcortical white matter score, whereas depression correlated with subcortical white matter score but not total Scheltens score. CONCLUSIONS: There is a characteristic pattern of MR imaging abnormalities in CADASIL that aids in differential diagnosis; however, some characteristic features, such as anterior temporal pole involvement, can be absent. MR imaging lesion load correlated with some clinical features including stroke and dementia, whereas depression is more common in individuals with deep white matter changes.     

Temporomandibular joint diagnostics using CBCT

The present review will give an update on temporomandibular joint (TMJ) imaging using CBCT. It will focus on diagnostic accuracy and the value of CBCT compared with other imaging modalities for the evaluation of TMJs in different categories of patients; osteoarthritis (OA), juvenile OA, rheumatoid arthritis and related joint diseases, juvenile idiopathic arthritis and other intra-articular conditions. Finally, sections on other aspects of CBCT research related to the TMJ, clinical decision-making and concluding remarks are added. CBCT has emerged as a cost- and dose-effective imaging modality for the diagnostic assessment of a variety of TMJ conditions. The imaging modality has been found to be superior to conventional radiographical examinations as well as MRI in assessment of the TMJ. However, it should be emphasized that the diagnostic information obtained is limited to the morphology of the osseous joint components, cortical bone integrity and subcortical bone destruction/production. For evaluation of soft-tissue abnormalities, MRI is mandatory. There is an obvious need for research on the impact of CBCT examinations on patient outcome.     

常染色体显性遗传性脑动脉病伴皮层下梗死和白质脑病的颅脑MRI表现

目的 提高对常染色体显性遗传性脑动脉病伴皮层下梗死和白质脑病(CADASIL)的颅脑MRI表现的认识.方法 对一家系2代5例患者进行头颅常规MR和MR血管成像(MRA)检查.对经Notch3基因检查或皮肤组织活检超微病理检查确诊的3例和经MRI与临床诊断的1例CADASIL的MRI资料进行分析.结果 MR检查的5例中4例CADASIL均获得明确诊断,1例排除诊断.4例CADASIL均见两侧颞叶、额叶和顶叶大致对称性皮层下与侧脑室旁白质病灶,呈长T1、长T2信号,但枕叶累及甚少且皮层不受累;O'Sullivan征阳性4例,皮层下腔隙性损害(SLLs)征阳性2例;3例半卵圆中心可见多发圆形或卵圆形囊性梗死即"黑洞",4例均见多发圆点状血管周间隙即"胡椒罐盖"样征象;4例全部显示胼胝体单发或多发斑片状显著长T1、长T2信号,其中2例伴萎缩;内囊前肢与外囊均受累,呈"人"字征;基底节和脑干可见单发或多发陈旧性腔隙性梗死灶;1例伴右侧小脑小片状梗死灶;4例全部有轻度至中度的脑干、小脑和大脑萎缩;MRA颅内Ⅰ-Ⅲ级较大动脉均未见明显异常.结论 CADASIL的颅脑MRI表现具有一定的特征性,可为CADASIL的初诊和筛选提供重要依据.     

Movement disorders: role of imaging in diagnosis

Magnetic resonance imaging (MRI and single-photon emission computed tomography (SPECT) have a considerable role in the diagnosis of the single patient with movement disorders. Conventional MRI demonstrates symptomatic causes of parkinsonism but does not show any specific finding in Parkinson's disease (PD). However, SPECT using tracers of the dopamine transporter (DAT) demonstrates an asymmetric decrease of the uptake in the putamen and caudate from the earliest clinical stages. In other degenerative forms of parkinsonism, including progressive supranuclear palsy (PSP), multisystem atrophy (MSA), and corticobasal degeneration (CBD), MRI reveals characteristic patterns of regional atrophy combined with signal changes or microstructural changes in the basal ganglia, pons, middle and superior cerebellar peduncles, and cerebral subcortical white matter. SPECT demonstrates a decreased uptake of tracers of the dopamine D2 receptors in the striata of patients with PSP and MSA, which is not observed in early PD. MRI also significantly contributes to the diagnosis of some inherited hyperkinetic conditions including neurodegeneration with brain iron accumulation and fragile-X tremor/ataxia syndrome by revealing characteristic symmetric signal changes in the basal ganglia and middle cerebellar peduncles, respectively. A combination of the clinical features with MRI and SPECT is recommended for optimization of the diagnostic algorithm in movement disorders.     

Megalencephalic leukoencephalopathy with subcortical cysts: report of 4 new cases

Megalencephalic leukoencephalopathy with subcortical cysts or Van der Knapp disease is a rare entity that has recently been identified. It is characterized by the presence of macrocephaly, epilepsy and a slowly progressive spastic cerebellar syndrome. The culprit MLC1 gene is located on chromosome 22. MRI provides valuable data for diagnosis characterized by diffuse white matter lesions with subcortical cysts. We report four cases of megalencephalic leukoencephalopathy with subcortical cysts from two different families.     

Neurosyphilis: MRI features and their phenotypic correlation in a cohort of 35 patients from a tertiary care university hospital

Introduction

The clinical and MR imaging features of neurosyphilis are highly varied. In this study, we describe the spectrum of the imaging findings in patients with neurosyphilis.

Methods

The MR imaging observations of 35 patients diagnosed to have neurosyphilis on the basis of cerebrospinal fluid reactive for the Venereal Disease Research Laboratory test were reviewed.

Results

All the 35 patients, including four with human immunodeficiency virus coinfection, met the CDC diagnostic criteria for neurosyphilis. Patients were classified into three groups: (1) neuropsychiatric, (2) meningovascular, and (3) myelopathic, based on the dominant clinical manifestations. Fourteen patients with neuropsychiatric manifestations showed diffuse cerebral atrophy (14), parenchymal signal changes in the mesial temporal region (2) and temporal and basifrontal regions (1), infarcts (3), and nonspecific white matter changes (3). Eleven patients with meningovascular form showed infarcts (6), diffuse cerebral atrophy (3), signal changes in the mesial temporal region (3), sulcal exudates (1), progressive multifocal leukoencephalopathy (1), and a mass surrounding the carotid sheath (1). Spine imaging in ten patients with myelopathy showed long-segment signal changes (5), contrast enhancement (2), and dorsal column involvement (2). Three of these patients had normal spinal study. Six patients in the myelopathic group also underwent brain MRI that showed signal changes in the temporal region (2) and frontal region (1), multiple infarcts (1), and enhancing hypothalami (1). Three patients had normal study.

Conclusion

MRI abnormalities in neurosyphilis are protean and mimic of many other neurological disorders and thus require a high index of suspicion to reduce diagnostic omissions.     

Distribution of cranial MRI abnormalities in patients with symptomatic and subclinical CADASIL

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is a rare, inherited cause of early stroke and dementia, with a poor prognosis. This study was performed to clarify lesion appearance and pattern of lesion distribution in CADASIL. 20 members of a single family were tested for the CADASIL gene mutation and studied with cranial MRI. Scans were evaluated for lesion load and pattern of lesion distribution. 19 patients had cranial MRI, of whom 11 had normal MRI scans, were clinically unaffected and tested negative for the CADASIL gene mutation. The remaining eight patients had abnormal cranial MRI scans: seven patients were positive for the CADASIL gene mutation and one (untested) patient was severely clinically affected. Three of the patients who tested positive for the CADASIL gene mutation were clinically unaffected at the time of imaging. All eight patients with abnormal cranial MRI had subcortical white matter abnormalities, mostly in frontal and temporal lobes. Lesions involving the corpus callosum were present on sagittal T2 weighted images in four of five clinically affected and one of three clinically unaffected patients. Lesions involving the deep grey nuclei and the brain stem were common. On T1 weighted images, lesions were either poorly defined (confluent white matter hypointensity) or well defined (cystic infarcts or enlarged perivascular spaces). Atrophy was infrequent. Familiarity with the range of cranial MRI appearances may aid diagnosis of CADASIL. Recognition of cranial imaging features in asymptomatic CADASIL patients could prompt earlier diagnosis.     

Masthead,Volume 35, Issue 2

Magnetic resonance imaging (MRI and single‐photon emission computed tomography (SPECT) have a considerable role in the diagnosis of the single patient with movement disorders. Conventional MRI demonstrates symptomatic causes of parkinsonism but does not show any specific finding in Parkinson's disease (PD). However, SPECT using tracers of the dopamine transporter (DAT) demonstrates an asymmetric decrease of the uptake in the putamen and caudate from the earliest clinical stages. In other degenerative forms of parkinsonism, including progressive supranuclear palsy (PSP), multisystem atrophy (MSA), and corticobasal degeneration (CBD), MRI reveals characteristic patterns of regional atrophy combined with signal changes or microstructural changes in the basal ganglia, pons, middle and superior cerebellar peduncles, and cerebral subcortical white matter. SPECT demonstrates a decreased uptake of tracers of the dopamine D2 receptors in the striata of patients with PSP and MSA, which is not observed in early PD. MRI also significantly contributes to the diagnosis of some inherited hyperkinetic conditions including neurodegeneration with brain iron accumulation and fragile‐X tremor/ataxia syndrome by revealing characteristic symmetric signal changes in the basal ganglia and middle cerebellar peduncles, respectively. A combination of the clinical features with MRI and SPECT is recommended for optimization of the diagnostic algorithm in movement disorders. J. Magn. Reson. Imaging 2012 © 2012 Wiley Periodicals, Inc.     

Differential diagnosis of mesiotemporal lesions: case report of neurosyphilis

We report a clinical and imaging case of suspected herpes simplex encephalitis subsequently diagnosed as neurosyphilis based on positive antibodies in the CSF. MRI of the brain showed cortical and subcortical lesions in the mesial temporal region, septal area, insula and cingulated gyrus of the right cerebral hemisphere. Neurosyphilis should be included in the differential diagnosis of mesial temporal region lesions on MRI.     

Conventional and diffusion-weighted MRI in progressive multifocal leukoencephalopathy: new elements for identification and follow-up

PURPOSE: Progressive multifocal leukoencephalopathy (PML) is a serious disorder that primarily affects individuals with a suppressed immune system. Few semiological elements help clearly distinguish PML from other diseases included in the differential diagnosis. Moreover, the clinical course of disease may be chronic or rapidly progressive, with different magnetic resonance imaging (MRI) patterns. The purpose of this study was to confirm the diagnostic value of conventional MRI sequences combined with diffusion-weighted imaging (DWI) in PML to identify those patients with worst prognosis. MATERIALS AND METHODS: We used both conventional MRI sequences and DWI to monitor four male patients aged between 40 and 50 years affected by PML. In two patients, the disease rapidly led to death whereas the other two patients presented a chronic course. RESULTS: Conventional MRI sequences enable detection of the extension of white matter lesions. DWI permits more accurate differentiation of the disease progression front, which exhibits low signal intensity in apparent diffusion coefficient (ADC) maps, from the central gliotic area of demyelinisation, characterised by high ADC values. Patients with rapidly evolving PML have a clear progression front on DWI, which seems to be very tenuous, if not absent, during the quiescent phases of the disease. CONCLUSIONS: The addition of DWI sequences to conventional MRI seems to be a valid method for accurately diagnosing PML and establishing the degree of disease progression.     

Transient leukoencephalopathy after intrathecal methotrexate mimicking stroke

Methotrexate (MTX) is an indispensable antimetabolite for the treatment of oncological and immunological disorders in all age groups. It can be administrated intravenously as well as intrathecally and may be used alone or in combination with other drugs. Chronic leukoencephalopathy is a well-known side effect of MTX, especially in conjunction with intrathecal administration. However, acute neurotoxicity with confusion, disorientation, seizures, and focal deficits may also be seen. This can clinically mimic stroke with restricted diffusion on MRI. However, unlike stroke, there is resolution of clinical and imaging findings within 1–4 weeks. We report two cases of transient leukoencephalopathy following intrathecal methotrexate, with complete clinical and radiological resolutions on follow-up.     

Progressive multifocal leukoencephalopathy: analysis of lesion development with diffusion-weighted MRI

Progressive multifocal leukoencephalopathy (PML), caused by replication of JC virus in oligodendrocytes of immunocompromised patients, is diagnosed by polymerase chain reaction-based demonstration of JC virus DNA. We investigated whether MRI might be used to assess disease activity. Diffusion-weighted imaging (DWI) was obtained in two patients with PML, in whom it was the only MRI sequence on which we could identify areas of progressive disease. The extent of abnormal diffusion appeared to correlate with the speed of clinical progression. DWI would thus seem to be of value in patients with PML.     

Neuroradiology of human prion diseases,diagnosis and differential diagnosis

Human transmissible spongiform encephalopathies (TSEs), or prion diseases, are invariably fatal conditions associated with a range of clinical presentations. TSEs are classified as sporadic [e.g. sporadic Creutzfeldt–Jakob disease (sCJD), which is the most frequent form], genetic (e.g. Gerstmann–Straussler–Scheinker disease, fatal familial insomnia, and inherited CJD), and acquired or infectious (e.g. Kuru, iatrogenic CJD, and variant CJD). In the past, brain imaging played a supporting role in the diagnosis of TSEs, whereas nowadays magnetic resonance imaging (MRI) plays such a prominent role that MRI findings have been included in the diagnostic criteria for sCJD. Currently, MRI is required for all patients with a clinical suspicion of TSEs. Thus, MRI semeiotics of TSEs should become part of the cultural baggage of any radiologist. The purposes of this update on the neuroradiology of CJD are to (i) review the pathophysiology and clinical presentation of TSEs, (ii) describe both typical and atypical MRI findings of CJD, and (iii) illustrate diseases mimicking CJD, underlining the MRI key findings useful in the differential diagnosis.     

海洛因白质脑病的CT与MRI诊断

目的 研究CT与MRI对烫吸海洛因蒸汽引起海绵状白质脑病的特征性影像学诊断价值。方法 对2例烫吸海洛因引起的海绵状白质脑病的患者进行了临床和CT与MRI观察，查阅中外文献，对该病影像学特征结合临床表现、病理组织改变进行总结与讨论。结果 2例患者以小脑性共济失调、智力减退为主要临床表现，CT显示对称性分布的小脑白质、大脑白质为主的低密度改变；MRI显示对称性分布的小脑齿状核，大脑半球半卵圆中心、双基底节内囊、中脑、桥脑白质纤维为主的高信号改变。结论 烫吸海洛因引起海绵状白质脑病的CT与MRI影像学改变具有特征性，能为临床诊断提供可靠依据，从而使本病能够得到早期确诊。     

Lung MRI with hyperpolarised gases: current & future clinical perspectives

The use of pulmonary MRI in a clinical setting has historically been limited. Whilst CT remains the gold-standard for structural lung imaging in many clinical indications, technical developments in ultrashort and zero echo time MRI techniques are beginning to help realise non-ionising structural imaging in certain lung disorders. In this invited review, we discuss a complementary technique – hyperpolarised (HP) gas MRI with inhaled ³He and ¹²⁹Xe – a method for functional and microstructural imaging of the lung that has great potential as a clinical tool for early detection and improved understanding of pathophysiology in many lung diseases. HP gas MRI now has the potential to make an impact on clinical management by enabling safe, sensitive monitoring of disease progression and response to therapy. With reference to the significant evidence base gathered over the last two decades, we review HP gas MRI studies in patients with a range of pulmonary disorders, including COPD/emphysema, asthma, cystic fibrosis, and interstitial lung disease. We provide several examples of our experience in Sheffield of using these techniques in a diagnostic clinical setting in challenging adult and paediatric lung diseases.