Typical Magnetic Resonance Imaging Findings Research Articles

An intriguing case of rapidly progressive dementia: Creutzfeldt–Jakob Disease

Although no formal definition exists for what constitutes a rapidly progressive dementia (RPD), generally we use the term when dementia occurs in <1–2 years from illness onset, but more commonly over weeks to months. Prion diseases are the prototypical causes of RPD, but reversible causes of RPD might mimic prion disease and should always be considered in a differential diagnosis. We report the case of a 65-year-old male with progressive dementia and typical neurologic symptoms, myoclonic jerks, and magnetic resonance imaging findings of Creutzfeldt–Jakob disease (CJD). This case highlights the need for a high index of suspicion to diagnose CJD.

Atypical Cerebral Manifestations of Disseminated Mycobacterium tuberculosis.

We investigated the patterns of cerebral manifestations in patients with underlying pulmonary or extrapulmonary tuberculosis or disseminated tuberculosis. From January 2010 to September 2016, brain magnetic resonance imaging (MRI) scans were obtained to evaluate cerebral manifestations in patients with underlying pulmonary or extrapulmonary tuberculosis. We also included patients with drug-resistant tuberculosis or disseminated tuberculosis. MRI findings of tuberculous meningitis and tuberculoma were classified as typical; other MRI findings were classified as atypical. Demographic data, risk factors, and drug regimens were collected and analyzed. Twenty-two patients were diagnosed with cerebral tuberculosis. Cerebral tuberculosis was due to hematogenous spread from pulmonary tuberculosis (10 patients), spinal tuberculosis (8 patients), disseminated tuberculosis (3 patients), and unknown causes (1 patient). There were six patients with typical MRI findings (three patients with typical meningitis involving the basal cistern and supratentorium, one patient with tuberculomas, and two patients with both) and seven patients with atypical MRI findings [five patients with evidence of early meningitis, such as high signal intensity on fluid-attenuated inversion recovery (FLAIR) along the cerebellar folia, and two patients with only hydrocephalus]. Besides the typical sites of meningeal involvement, overlooked findings such as FLAIR abnormalities along the cerebellar folia or hydrocephalus should be checked for early detection of cerebral tuberculosis and initiation of the appropriate treatment against disseminated tuberculosis.

Systematic Review of Cysteine-Sparing NOTCH3 Missense Mutations in Patients with Clinical Suspicion of CADASIL.

CADASIL (cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy) is caused by mutations in the NOTCH3 gene, affecting the number of cysteines in the extracellular domain of the receptor, causing protein misfolding and receptor aggregation. The pathogenic role of cysteine-sparing NOTCH3 missense mutations in patients with typical clinical CADASIL syndrome is unknown. The aim of this article is to describe these mutations to clarify if any could be potentially pathogenic. Articles on cysteine-sparing NOTCH3 missense mutations in patients with clinical suspicion of CADASIL were reviewed. Mutations were considered potentially pathogenic if patients had: (a) typical clinical CADASIL syndrome; (b) diffuse white matter hyperintensities; (c) the 33 NOTCH3 exons analyzed; (d) mutations that were not polymorphisms; and (e) Granular osmiophilic material (GOM) deposits in the skin biopsy. Twenty-five different mutations were listed. Four fulfill the above criteria: p.R61W; p.R75P; p.D80G; and p.R213K. Patients carrying these mutations had typical clinical CADASIL syndrome and diffuse white matter hyperintensities, mostly without anterior temporal pole involvement. Cysteine-sparing NOTCH3 missense mutations are associated with typical clinical CADASIL syndrome and typical magnetic resonance imaging (MRI) findings, although with less involvement of the anterior temporal lobe. Hence, these mutations should be further studied to confirm their pathological role in CADASIL.

Cytotoxic Lesions of the Corpus Callosum That Show Restricted Diffusion: Mechanisms, Causes, and Manifestations.

Cytotoxic lesions of the corpus callosum (CLOCCs) are secondary lesions associated with various entities. CLOCCs have been found in association with drug therapy, malignancy, infection, subarachnoid hemorrhage, metabolic disorders, trauma, and other entities. In all of these conditions, cell-cytokine interactions lead to markedly increased levels of cytokines and extracellular glutamate. Ultimately, this cascade can lead to dysfunction of the callosal neurons and microglia. Cytotoxic edema develops as water becomes trapped in these cells. On diffusion-weighted magnetic resonance (MR) images, CLOCCs manifest as areas of low diffusion. CLOCCs lack enhancement on contrast material-enhanced images, tend to be midline, and are relatively symmetric. The involvement of the corpus callosum typically shows one of three patterns: (a) a small round or oval lesion located in the center of the splenium, (b) a lesion centered in the splenium but extending through the callosal fibers laterally into the adjacent white matter, or (c) a lesion centered posteriorly but extending into the anterior corpus callosum. CLOCCs are frequently but not invariably reversible. Their pathologic mechanisms are discussed, the typical MR imaging findings are described, and typical cases of CLOCCs are presented. Although CLOCCs are nonspecific with regard to the underlying cause, additional imaging findings and the clinical findings can aid in making a specific diagnosis. Radiologists should be familiar with the imaging appearance of CLOCCs to avoid a misdiagnosis of ischemia. When CLOCCs are found, the underlying cause of the lesion should be sought and addressed. ©RSNA, 2017 An earlier incorrect version of this article appeared online. This article was corrected on February 13, 2017.

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.

Magnetic resonance imaging in the assessment of brain involvement in alcoholic and nonalcoholic Wernicke's encephalopathy.

AIMTo present the typical and atypical magnetic resonance (MR) imaging findings of alcoholic and non-alcoholic Wernicke’s encephalopathy.METHODSThis study included 7 patients with Wernicke’s encephalopathy (2 men, 5 women; mean age, 52.3 years) that underwent brain MR examination between January 2012 and March 2016 in a single institution. Three patients were alcoholics and 4 patients were non-alcoholics. MR protocol included a T2-weighted sequence, a fluid attenuation inversion recovery (FLAIR) sequence, a diffusion-weighted sequence (b = 0 and 1000 s/mm2), and a contrast-enhanced MR sequence. All MR images were retrospectively reviewed at baseline and follow-up by two radiologists.RESULTSAll patients with Wernicke’s encephalopathy had bilateral areas showing high signal intensity on both T2-weighted and FLAIR MR images in the typical sites (i.e., the periaqueductal region and the tectal plate). Signal intensity abnormalities in the atypical sites (i.e., the cerebellum and the cerebellar vermis) were seen in 4 patients, all of which had no history of alcohol abuse. Six patients had areas with restricted diffusion in the typical and atypical sites. Four patients had areas showing contrast-enhancement in the typical and atypical sites. Follow-up MR imaging within 6 mo after therapy (intravenous administration of thiamine) was performed in 4 patients, and demonstrated a complete resolution of all the signal intensities abnormalities previously seen in all patients.CONCLUSIONMR imaging is valuable in the diagnosis of Wernicke’s encephalopathy particularly in patients presenting with atypical clinical symptoms, or with no history of alcohol abuse.

Prioritization of liver MRI for distinguishing focal lesions.

Liver cancer is one of the leading causes of cancer-related mortality worldwide. Magnetic resonance imaging (MRI) is a non-invasive imaging technique that is often used by radiologists for diagnosis and surgical planning. Analysis of a large amount of liver MRI data for each patient limits the radiologist's efficiency and may lead to misdiagnoses. The redundant MRI data, especially from dynamic contrast enhanced (DCE) sequences, is also a bottleneck in transmitting the images via the internet or PACS for remote consultancy in a reasonable amount of time. This study included 25 patients (aged between 20 and 70 years) with liver cysts (seven cases), hemangiomas (eight cases), or hepatic cell carcinomas (10 cases). DCE T1WI MRI was performed for all the patients. The diagnosis reference included typical MRI findings and post-surgery pathology. The methods were as follows: (i) MRI sequence pre-processing based on large vessels variation level set method to remove non-liver parts from MRI images; (ii) human visual model features (luminance, motion, and contour) extraction and fusion; (iii) anomaly-based MRI ranking; and (iv) methods assessment with the 25 patients' DCE MRI data. The prioritization methods applied to the DCE images could automatically assimilate and determine the content of the medical images, identifying the liver cysts, hemangiomas, and carcinomas. The average uniformity between radiologists and prioritization with the proposed method was 0.805, 0.838, and 0.818 for cysts, hemangiomas, and carcinomas, respectively, which indicates that the proposed method is an efficient method for liver DCE image prioritization.

Mutations in the histone methyltransferase gene KMT2B cause complex early-onset dystonia.

Histone lysine methylation, mediated by mixed-lineage leukemia (MLL) proteins, is now known to be critical in the regulation of gene expression, genomic stability, cell cycle and nuclear architecture. Despite MLL proteins being postulated as essential for normal development, little is known about the specific functions of the different MLL lysine methyltransferases. Here we report heterozygous variants in the gene KMT2B (also known as MLL4) in 27 unrelated individuals with a complex progressive childhood-onset dystonia, often associated with a typical facial appearance and characteristic brain magnetic resonance imaging findings. Over time, the majority of affected individuals developed prominent cervical, cranial and laryngeal dystonia. Marked clinical benefit, including the restoration of independent ambulation in some cases, was observed following deep brain stimulation (DBS). These findings highlight a clinically recognizable and potentially treatable form of genetic dystonia, demonstrating the crucial role of KMT2B in the physiological control of voluntary movement.

Diabetic muscle infarction with pelvic vein thrombosis: An uncommon presentation to the emergency department

Diabetic muscle infarction (DMI) occurs as a rare complication associated with long-standing, poorly controlled diabetes mellitus (DM) and typically presents as acute painful muscle swelling in the absence of trauma. It resolves spontaneously over a few weeks to months in most patients and generally has a good prognosis. However, the coexistence of deep vein thrombosis (DVT) with DMI may have an additional risk of complications such as pulmonary embolism, recurrent DVT, and post-thrombotic syndrome (PTS). Although the treatment for DMI is mainly analgesia, rest, and control of diabetes, the coexistence of extensive DVT and diabetic ketoacidosis (DKA) may demand anticoagulation and a multidisciplinary team approach. Its management may also involve the endocrinologist, hematologist, and occasionally an interventional radiologist or vascular surgeon. We report two cases of patients with DMI with extensive DVT that presented to our emergency department (ED) as acute non-traumatic swelling of the lower limb. The diagnosis of DMI in both the cases was based on the presence of characteristic clinical features and typical magnetic resonance imaging (MRI) findings. The patients were treated with anticoagulation therapy in addition to the management of DKA, and discharged with good recovery.

Imaging Features of Hypertrophic Olivary Degeneration.

Hypertrophic olivary degeneration (HOD) is a unique form of transneuronal degeneration caused by a disruption of the dentato-rubro-olivary pathway, also known as the triangle of Guillain-Mollaret. The triangle of Guillain-Mollaret is involved in fine voluntary motor control and consists of both the inferior olivary nucleus and the red nucleus on one side and the contralateral dentate nucleus. Clinically, patients classically present with symptomatic palatal myoclonus. Typical magnetic resonance imaging findings include T2-hyperintensity and enlargement of the inferior olivary nucleus evolving over time to atrophy with residual T2-hyperintensity. In this article, we provide a case-based illustration of the anatomy of the Guillain-Mollaret-triangle and the typical imaging findings of hypertrophic olivary degeneration.

Central Nervous Involvement in Patients with Fukuyama Congenital Muscular Dystrophy

Fukuyama congenital muscular dystrophy (FCMD), the second most common muscular dystrophy in the Japanese population, is an autosomal recessive disorder caused by mutations in the fukutin (FKTN) gene. The main features of FCMD are a combination of infantile-onset hypotonia, generalized muscle weakness, eye abnormalities and central nervous system involvement with mental retardation and seizures associated with cortical migration defects. The FKTN gene product is thought to be necessary for maintaining migrating neurons in an immature state during migration, and for supporting migration via α-dystroglycan in the central nervous system. Typical magnetic resonance imaging findings in FCMD patients are cobblestone lissencephaly and cerebellar cystic lesions. White matter abnormalities with hyperintensity on T(2)-weighted images are seen especially in younger patients and those with severe phenotypes. Most FCMD patients are mentally retarded and the level is moderate to severe, with IQs ranging from 30 to 50. In our recent study, 62% of patients developed seizures. Among them, 71% had only febrile seizures, 6% had afebrile seizures from the onset, and 22% developed afebrile seizures following febrile seizures. Most patients had seizures that were controllable with just 1 type of antiepileptic drug, but 18% had intractable seizures that must be treated with 3 medications.

Intradural epidermoid cyst with atypical magnetic resonance imaging and clinical presentation

Epidermoid cysts are a rare benign neoplasm of spine. They account for only 1% of all benign spinal tumors. These cysts are either congenital or acquired, like after repeated lumbar puncture. They can present anywhere in the spinal cord, and are intradural. They can be intra- or extra-medullary. As the cysts are slow growing, they are mostly reported after some sensorimotor or in some cases after bowel and bladder involvement. Typical magnetic resonance imaging (MRI) findings are a hyperintense signal on T2-weighted (T2W) and hypointense T2W images. Diagnosis is confirmed on histopathologic examination. The treatment is complete excision and if not then maximum debulking of the tumor. We present a case of 27-year-old male with only tingling and mild weakness in the left lower limb. He was diagnosed with intradural tumor with MRI findings showing hyperintense signal on T1-W and isointense signal on T2W images. This is an uncommon presentation. It was enmeshing around rootlets so had to be debulked. The diagnosis was confirmed on histopathologic examination. Postoperatively recovery was excellent with no neurological deficit.

Magnetic Resonance Imaging and GeneXpert: A Rapid and Accurate Diagnostic Tool for the Management of Tuberculosis of the Spine.

Study DesignRetrospective study.PurposeThe aim of this study was to analyze various diagnostic tools, including GeneXpert, for the management of tuberculosis of the spine.Overview of LiteratureTraditional diagnostic methods of microscopy, histology, and culture have low sensitivity and specificity for the management of tuberculosis of the spine.MethodsOf the 262 treated cases of spinal tuberculosis, data on 1 year follow-up was available for 217 cases. Of these, only 145 cases with a confirmed diagnosis were selected for retrospective analysis.ResultsIn 145 of the 217 patients (66.80%), diagnosis was confirmed on the basis of a culture. Of the 145 patients with a confirmed diagnosis, 98 (66.20%) patients were diagnosed on the basis of clinical presentation, whereas 123 (84.8%) exhibited a typical magnetic resonance imaging (MRI) picture. In 99 surgically treated patients, the diagnosis was confirmed on the basis of an intraoperative tissue biopsy. Among the 46 patients treated conservatively, 35 underwent a transpedicular biopsy, 4 patients underwent computed tomography-guided biopsy, 6 patients were diagnosed on the basis of material obtained from a cold abscess, and 1 patient underwent an open biopsy. The sensitivity of the culture for the detection of Mycobacterium tuberculosis was 66.80% (145/217) in our patients. Among the cases in which GeneXpert was used, the sensitivity for the detection of Mycobacterium tuberculosis was 93.4% (43/46). Moreover, the sensitivity of GeneXpert to detect rifampicin resistance was 100% (7/7) in our study.ConclusionsMajority of the patients with tuberculosis of the spine can be diagnosed on the basis of a typical radiological presentation via MRI. In our study, 84.8% cases exhibited typical MRI findings. For patients presenting with atypical MRI features, a rapid and accurate diagnosis is possible by combining GeneXpert with MRI. The combined use of MRI and GeneXpert is a rapid and highly sensitive tool to diagnose tuberculosis and rifampicin resistance in patients with tuberculosis of the spine. Furthermore, we achieved a 97.9% sensitivity for the detection of Mycobacterium tuberculosis and 100% sensitivity for the detection of rifampicin resistance in our study.

Septo-optic dysplasia: Magnetic Resonance Imaging findings

Septo-optic dysplasia is a rare congenital disorder involving brain and optic pathways. We present typical Magnetic Resonance Imaging (MRI) findings of a case of Septo-optic dysplasia in a 19 year old female patient.

Multiple Sclerosis and Related Disorders

Multiple sclerosis (MS) is a relatively common cause of neurologic symptoms and disability in young adults. The distinguishing pathologic features of MS are loss of myelin and inflammation in the central nervous system (CNS). The myelin sheath is essential for rapid conduction of nerve signals along large-diameter axons. Oligodendrocytes produce and maintain myelin in the CNS, and Schwann cells produce and maintain myelin in the peripheral nerves. In addition to MS, there are a number of related disorders causing demyelination, inflammation, or both in the CNS. This chapter discusses MS and related disorders, including neuromyelitis optica, optic neuritis, acute disseminated encephalomyelitis, transverse myelitis, Behçet syndrome, neurosarcoidosis, inherited demyelinating diseases (leukodystrophies, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy [CADASIL]), and virus-induced demyelination (progressive multifocal leukoencephalopathy, subacute sclerosing panencephalitis). The section on MS covers epidemiology, etiology/genetics, pathogenesis, diagnosis, differential diagnosis, management, and prognosis. Figures include organization of the microenvironment of larger-diameter axons, typical magnetic resonance imaging findings in MS and neuromyelitis optica, postgadolinium images of the cervical spine in MS, and an approach to treatment of relapsing-remitting MS. Tables list MS and related disorders, distribution of neurologic deficits at the onset of MS, differential diagnosis of MS, disease-modifying therapies for relapsing-remitting MS, and selected leukodystrophies, as well as diagnostic criteria and selected symptomatic therapies for MS. This chapter contains 3 highly rendered figures, 7 tables, 82 references, 1 teaching slide set, and 5 MCQs.

Multiple Sclerosis and Related Disorders

Multiple sclerosis (MS) is a relatively common cause of neurologic symptoms and disability in young adults. The distinguishing pathologic features of MS are loss of myelin and inflammation in the central nervous system (CNS). The myelin sheath is essential for rapid conduction of nerve signals along large-diameter axons. Oligodendrocytes produce and maintain myelin in the CNS, and Schwann cells produce and maintain myelin in the peripheral nerves. In addition to MS, there are a number of related disorders causing demyelination, inflammation, or both in the CNS. This chapter discusses MS and related disorders, including neuromyelitis optica, optic neuritis, acute disseminated encephalomyelitis, transverse myelitis, Behçet syndrome, neurosarcoidosis, inherited demyelinating diseases (leukodystrophies, cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy [CADASIL]), and virus-induced demyelination (progressive multifocal leukoencephalopathy, subacute sclerosing panencephalitis). The section on MS covers epidemiology, etiology/genetics, pathogenesis, diagnosis, differential diagnosis, management, and prognosis. Figures include organization of the microenvironment of larger-diameter axons, typical magnetic resonance imaging findings in MS and neuromyelitis optica, postgadolinium images of the cervical spine in MS, and an approach to treatment of relapsing-remitting MS. Tables list MS and related disorders, distribution of neurologic deficits at the onset of MS, differential diagnosis of MS, disease-modifying therapies for relapsing-remitting MS, and selected leukodystrophies, as well as diagnostic criteria and selected symptomatic therapies for MS. This chapter contains 3 highly rendered figures, 7 tables, 82 references, 1 teaching slide set, and 5 MCQs.

MRI characteristics of intraductal papilloma

Intraductal papilloma (IDP) is the most common pathological finding in women with pathological nipple discharge. Magnetic resonance imaging (MRI) has shown potential for characterizing breast tumors; however, MRI findings of IDPs are inconclusive, and certain diagnostic standards are lacking. To characterize the MRI features of IDP from a relatively large cohort. We retrospectively reviewed from 358 women with IDPs that were confirmed by histopathology. The clinical and imaging findings in 70 patients who underwent preoperative MRI were analyzed. MRI analyses included morphology and dynamic contrast-enhanced MRI. In 70 patients, 77 IDPs were detected on MRI, which revealed the following three patterns: small luminal mass papillomas; tumor-like papillomas; and MRI-occult papillomas. Fourteen IDPs involved small, oval, smooth, and contrast-enhanced masses at the posterior end of the enlarged duct corresponding to small luminal mass papillomas. Seven IDPs had large diameters along the direction of the breast duct, indicating the typical MRI findings for IDP. Of 47 tumor-like papillomas, 16 cases showed large diameters along the direction of the breast duct and close to the nipple (within 4 cm), seven cases resembled invasive breast cancer on MRI, and the remaining 24 were (24/47) undistinguishable from other benign breast diseases. Sixteen IDPs were MRI-occult papillomas that could not be distinguished from the surrounding benign disease by either contrast-enhanced MRI or fat-suppressed T2-weighted MRI. Small luminal mass papillomas or tumor-like papillomas with the largest diameters along the direction of the breast duct and close to the nipple (within 4 cm) might be the typical MRI findings for IDPs.

Creutzfeldt-Jakob disease: A great masquerade in neurology, a rare case report from South India

Creutzfeldt-Jakob disease (CJD) is a rare, fatal neurodegenerative disease caused by an infectious protein called prion and is characterized by spongiform changes, neuronal loss, reactive astrocytic proliferation, and accumulation of pathologic cellular protein. Clinical presentation of CJD is characterized by rapidly progressive dementia, neurologic symptoms and visual impairment, and the development of akinetic mutism, which can mimic many neurological conditions. The diagnosis is based on clinical presentation, electroencephalogram, and typical cerebrospinal fluid and magnetic resonance imaging (MRI) findings. Literature on the incidence and prevalence of CJD is lacking in South India. We report the case of a 57-year-old woman with progressive dementia and typical neurologic symptoms, myoclonic jerks, and MRI findings of CJD. This case highlights the need for a high index of suspicion to diagnose CJD.

A case of status epilepticus: A giant panda dropped the hint

Wilson's disease can manifest as neurological disorder without hepatic involvement. However, first presentation as status epilepticus is extremely rare. Herein, we report a case where a 21-year-old male presented with status epilepticus. Clinical background, biochemical tests and typical magnetic resonance imaging findings in the form of Face of giant Panda sign confirmed the diagnosis of Wilson's disease.

Neurocognitive impairment in Susac syndrome: Magnetic resonance imaging and Tc-99m hexamethylpropyleneamine oxime single photon emission computed tomography correlation.

Susac syndrome is a clinical triad of branch retinal artery occlusions, sensorineural hearing loss, and encephalopathy. The characteristic central corpus callosum involvement in Susac syndrome is readily recognizable on conventional magnetic resonance imaging (MRI); however, the neurocognitive effect of these lesions is not well-understood. We present a case of Susac syndrome with typical MRI findings of central callosal lesions at diagnosis. The patient had a protracted clinical course and did not respond well to immunosuppression therapy. Follow-up brain single photon emission computed tomography with Tc-99m hexamethylpropyleneamine oxime revealed marked unilateral frontoparietal and temporal lobe hypoperfusion. Our case highlights the utility of functional neuroimaging to uncover the possible underlying white matter dysfunction, which is not otherwise detectable with conventional MRI techniques.