Atypical Magnetic Resonance Imaging Research Articles

Diagnostic errors in assessing magnetic resonance imaging semiotics of primary extracerebral tumors: a case series

Primary extracerebral tumors are represented by benign and malignant neoplasms of the meninges and cranial nerves. Their presurgical differential diagnosis is based on the analysis of magnetic resonance imaging semiotics. The critically significant aspects for classifying tumors of this group include the following: neoplasm structure, contrast enhancement type, delimiting from the brain tissue, and relationship with the meninges or cranial nerves. Differential diagnosis of extracerebral tumors based on visual analysis of magnetic resonance imaging data is generally not challenging because most tumors have typical magnetic resonance imaging semiotics. However, in cases with atypical magnetic resonance imaging signs, reliable differentiation of tumors can be challenging. Moreover, the greatest complexity is the differentiation of meningioma grades, distinction between solitary fibrous tumors and meningiomas, and identification of the tumor type when localized in the cerebellopontine angles. The case series presented the most typical features leading to errors in the differential diagnosis of primary extracerebral tumors. All the presented tumors were verified with postsurgical histological examination. The analysis of the case reports demonstrates that a review of the combined semiotic signs can lower the number of diagnostic errors.

Transient biopsy-proven progressive multifocal leukoencephalopathy-immune reconstitution inflammatory syndrome (PML-IRIS) in an elderly woman without known immunodeficiency: a case report

BackgroundProgressive multifocal leukoencephalopathy (PML) is a severe opportunistic brain disease caused by lytic JC polyomavirus (JCPyV) replication in oligodendrocytes. Although JCPyV infection is common in the general population, PML almost exclusively occurs in patients immunocompromised due to untreated HIV/AIDS, haematological malignancies, primary immunodeficiencies, solid organ transplantation, or immunomodulatory treatment of autoimmune diseases. There is no effective antiviral treatment, and recovery depends on immune reconstitution. Paradoxically, initiation of antiretroviral therapy for HIV/AIDS or interruption of immunomodulating treatment can worsen the clinical manifestations due to immune reconstitution inflammatory syndrome (IRIS). Here, we report an unusual case of spontaneous IRIS in a 76-year-old immunocompetent woman, unmasking PML and leading to unexpected recovery.Case presentationThe patient was admitted to the hospital due to psychosis, speech impairment, and behavioral changes over the last three months. She had previously been healthy, except for a cerebellar stroke secondary to paroxysmal atrial fibrillation. Magnetic resonance imaging (MRI) revealed multiple contrast-enhancing white matter lesions suspicious of cancer metastases. Due to suspicion of edema, dexamethasone was administered, and the patient was released while waiting for a stereotactic brain biopsy. Eight days later, she suffered tonic seizures and was readmitted. Intravenous levetiracetam gave rapid effect, but the patient was paranoid and non-cooperative, and dexamethasone was unintentionally discontinued. Ten days later, the brain biopsy revealed demyelination, abundant perivascular T cells, macrophages, and scattered JCPyV-infected oligodendrocytes, rendering the diagnosis of PML-IRIS. The cerebrospinal fluid contained low amounts of JCPyV-DNA, and plasma contained high levels of anti-JCPyV immunoglobulin G. Despite extensive immunological testing, no evidence of immunodeficiency was found. The patient gradually recovered clinically and radiologically. More than 19 months after diagnosis, the patient has only a slight impairment in language and behavior.ConclusionsAn apparently immunocompetent elderly person developed clinically symptomatic PML, which spontaneously resolved with symptoms and signs of IRIS. The atypical MRI lesions with contrast enhancement and the lack of known immunological risk factors for PML delayed the diagnosis, eventually proved by biopsy. PML and PML-IRIS should be considered in the differential diagnosis of patients presenting CNS symptoms and focal lesions with contrast enhancement on MRI.

A comprehensive MRI analysis of osteoid osteomas in patients with diverse radiological features across various regions.

Magnetic resonance imaging (MRI), which does not involve ionizing radiation, is the preferred imaging modality for diagnosing osteoid osteoma (OO), an ailment more common in children and young adults. This study aims to perform a literature review and delineate the MRI findings of OO lesions in patients exhibiting varying radiological features across different regions. A retrospective study included 63 patients diagnosed with OO through MRI, assessed independently by two blinded radiologists using both standard and dynamic contrast-enhanced MRI techniques. After excluding 7 patients with prior biopsy, surgery, or RFA, the study included 56 patients with 57 lesions. Of 57 lesions evaluated, 50 were in long, and 7 in flat bones. One patient presented with two separate nidi within the intertrochanteric region. Most of the lesions, 49 (86%), were extra-articular, while 8 (14%) were intra-articular. The nidus was intracortical in 45 (78.9%) patients, intramedullary in 5 (8.8%), subperiosteal in 5 (8.8%), and endosteal in 2 (3.5%). Average nidus diameter was 7.02 ± 2.64 mm (3-12.6 mm). Central nidal calcification was present in 68.4% (n = 39) cases. Contrast enhancement was intense at 90.5%, moderate at 9.5%. Reactive sclerosis around the nidus was severe (50.9%), moderate (22.8%), and mild (26.3%). Bone marrow edema was severe (70.2%), moderate (14.0%), and mild (15.8%). Soft tissue edema was identified in 77.2% of all lesions. To minimize delays in diagnosis and treatment, radiologists should become acquainted with the typical OO MRI findings and the atypical MRI findings that might be mistaken for other conditions.

Case series on neuroimaging spectrum of Wilson’s disease: knowing the known and the uncommonly known

BackgroundWilson’s disease is an inherited disease characterized by impaired copper metabolism that causes damage to many organs, including the brain. Patients having neurological involvement usually present with varied neuropsychiatric symptoms. Magnetic resonance imaging (MRI) Brain plays an indispensable role in identifying the structural involvement in these patients, aiding in early accurate diagnosis and timely management. Typically, basal ganglia, thalami and brainstem are involved, with bright claustrum sign, face of giant panda sign and miniature panda signs on MRI.ConclusionsHaving knowledge about the commonly encountered and known MRI brain findings in Wilson’s disease are essential in aiding accurate diagnosis and initiating early management. However, identifying the Atypical MRI brain characteristics is all the more imperative and should be considered in patients with prolonged or severe disease or in patients with rapid clinical progression and in patients showing poor response to treatment.

Cerebellar Lesions: Atypical Magnetic Resonance Imaging Findings in Wernicke's Encephalopathy.

Cerebellar Lesions: Atypical Magnetic Resonance Imaging Findings in Wernicke's Encephalopathy.

Bone Marrow Necrosis with Underlying Skeletal Lymphoma Evaluated by 18F-FDG PET/CT and MRI.

Bone marrow necrosis (BMN) is usually associated with malignancies and is characterized by multiple geographic signal abnormalities on magnetic resonance imaging (MRI). We report a 28-year-old female with BMN and underlying diffuse large B-cell lymphoma. Diffuse abnormal signal intensities through the vertebral column were demonstrated on her pretreatment MRI, and the diagnosis of BMN was challenging. Positron emission tomography/computed tomography (PET/CT) for lymphoma staging showed multiple decreased or absent 18F-fluorodeoxyglucose (18F-FDG) uptake within the vertebrae and pelvis. Marrow biopsy pathological examination showed lymphoma infiltration and massive necrosis. On the follow-up MRI obtained approximately 21 months after the PET/CT scan, multiple geographic abnormal signal intensities were detected within the vertebral column and were consistent with the areas of decreased 18F-FDG uptake on PET/CT. This case indicates that 18F-FDG PET/CT is helpful in the diagnosis of BMN with atypical MRI appearances.

Typical and atypical MRI abnormalities in Wernicke's encephalopathy: Correlation with blood vitamin B1 levels

PurposeClinical features of Wernicke's encephalopathy (WE) confirmed strictly through the low blood vitamin B1 (VB1) levels are limited. This study aimed to analyse magnetic resonance imaging (MRI) findings, and clinical characteristics, in patients with WE who have confirmed low blood VB1 levels. MethodsClinical and laboratory records of 12 consecutive patients with WE admitted to our hospital during the past 11 years were reviewed. The WE diagnosis was confirmed based on low blood VB1 levels and the presence of at least one of the classical triad. ResultsOphthalmoplegia and nystagmus were recorded in 75% and 50% of the patients, respectively. Eleven of 12 patients presented with consciousness disturbance/memory loss. All patients experienced gait disturbances. Eight of the 12 patients exhibited MRI abnormalities at typical sites (the dorsal midbrain [n = 7], medial thalamus [n = 6], mammillary bodies [n = 5], and dorsal pons [n = 5]). Of the 12 patients, six showed abnormalities at atypical sites (the splenium of the corpus callosum [n = 4], fornix [n = 3], cerebral cortex [n = 2], cerebellar vermis [n = 2], and dorsal medulla [n = 1]). Patients with positive MRI abnormalities had significantly lower blood VB1 levels than those without abnormalities (9.5 vs. 16.0 ng/mL). ConclusionsIn cases of confirmed WE with low blood VB1 levels, the corpus callosum, fornix, and cerebral cortex were more frequently involved than in previous studies. MRI abnormalities at both typical and atypical sites were correlated with low blood VB1 levels in WE, suggesting that lower blood VB1 levels are associated with more severe brain damage in patients with WE.

Atypical magnetic resonance imaging findings of a vertebral melanotic melanoma in a dog

AbstractAn 8‐year‐8‐month‐old whippet was investigated by magnetic resonance imaging for acute thoracolumbar discomfort and pelvic limb stiffness, which had progressed to severe ambulatory paraparesis and proprioceptive ataxia of the pelvic limbs in the 24 hours before presentation. An aggressive, extradural T10 vertebral mass‐like lesion was identified, with resultant marked compression of the spinal cord. The lesion was heterogeneously T2‐weighted hyperintense and moderately T1‐weighted hyperintense relative to the adjacent vertebrae and paravertebral musculature. Cytological analysis of the lesion was consistent with a melanotic melanoma, which was confirmed by histopathological analysis and immunohistochemistry. The vertebral column is an uncommon location for either primary or metastatic melanomas in both humans and veterinary species. This lesion was particularly unusual in that its imaging characteristics were not typical for melanotic melanoma. This case report illustrates the unusual anatomical and imaging features of this tumour and outlines the diagnostic considerations pertinent to this case.

Extradural lumbar arteriovenous fistula imitating a synovial cyst: illustrative case.

Spinal dural arteriovenous fistula is the most common spinal vascular malformation. It usually presents with neurological deficits due to venous congestive myelopathy. Sometimes, however, the symptoms are radicular and can imitate those of a disc hernia or synovial cyst. In this illustrated case, a 34-year-old male patient presented with radicular pain due to nerve root compression. In the magnetic resonance imaging (MRI) examination of the spine, a synovial cyst was suspected, so the patient underwent no further examination before surgery. Intraoperatively, the authors were surprised to see a vascular malformation, which was shown to be an extradural arteriovenous fistula according to the histopathological examination. In atypical MRI findings of the spine, vascular malformations should be considered. In cases with a spinal dural arteriovenous fistula, the thrombosis risk can be high and lead to a need for prolonged anticoagulation.

Slow-growing WNT medulloblastoma with atypical magnetic resonance imaging findings: illustrative case.

Medulloblastomas, with four molecular subgroups, are generally rapid-growing tumors with significant contrast enhancement and well-defined margins. However, each subgroup's clinical features, including disease time course and imaging characteristics, are not well defined. The authors describe the case of a 15-year-old female who presented with a 7-month history of impaired left-hand movement and was found to have a lesion on the dorsal side of the fourth ventricle. T2-weighted magnetic resonance imaging (MRI) at the patient's first presentation showed diffuse hyperintense signal without apparent mass, and gadolinium-enhanced T1-weighted imaging showed very slight contrast enhancement. In 1 month, her symptoms progressed, and follow-up MRI revealed an increase in the size of the lesion, showing greater diffusion restriction and contrast enhancement. She underwent gross-total resection, and pathology was consistent with classic medulloblastoma. Genetic analysis of the tumor confirmed the wingless (WNT) molecular subgroup. Adjuvant chemotherapy and proton beam therapy were performed. At the 18-month follow-up, MRI showed no recurrence of disease. Slow-growing medulloblastoma is very rare and not known to be associated with a specific molecular subgroup. Here, the authors report a case of slow-growing WNT medulloblastoma, indicating that slow growth may be a feature of this subgroup.

The current and future role of the MRI radiographer in radiation oncology: A collaborative, experiential reflection on the Australian rollout of dedicated MRI simulators.

Magnetic Resonance Imaging (MRI) has proven value in radiotherapy treatment planning (RTP). MRI provides excellent soft tissue contrast, and improves lesion detection, definition and extent, allowing for increased conformal treatment. Recent installation of dedicated MRI simulators and MRI-guided linear accelerators (MR Linacs) within radiation oncology departments has led to a sudden and rapid expansion in the scope of practice for many radiation therapists and MRI radiographers. The lack of current recommendations, guidelines and credentialing for both MRI radiographers and radiation therapists working within these atypical MRI environments poses a significant challenge for the education and training of staff, and the safe operation of these units. This commentary discusses current pathways for radiographers and radiation therapists entering the emerging field of MRI-guided radiation oncology, and the future role of the MRI radiographer in addressing the unique issues found in non-standard MRI environments. The authors draw on their collective experience as MRI radiographers assisting the rollout of dedicated MRI simulators in radiation oncology departments across Australia and reflect on the need for close collaboration between radiographers, radiation therapists and their respective departments. There is also a critical role for professional bodies to play in supporting existing and future roles in MRI and recognising advanced practitioner scope of practice.

The Characteristics of magnetic resonance imaging and immunohistochemical findings in de-differentiated liposarcoma.

Radiological imaging in Dedifferentiated liposarcoma (DDLPS) often shows the coexistence of fatty and non-fatty solid components; however, it has been shown that when fatty components were not identified on magnetic resonance imaging (MRI), the diagnosis of DDLPS would not have been diagnosed if immunohistochemical (IHC) staining had not been performed. The aim of this study was to investigate the pattern of MRI and relationship between MRI and IHC findings in DDLPS. We retrospectively reviewed the cases of 25 patients with DDLPS. To identify the MRI spectrum of DDLPS, tumors were classified into the following four categories based on MRI findings: I = a well-defined fatty mass and juxtaposed well-defined non-fatty mass, II = a non-fatty component within a predominantly fatty mass, III = a focal fatty component within a large non-fatty mass, and IV = a non-fatty mass with atypical MRI findings. IHC staining for CDK4, MDM2, and p16 were evaluated. Category IV tumor was the most common tumor in this population. Of the 22 patients who underwent IHC staining, MDM2, CDK4, and p16 were positive in 21, 20, and 19 patients, respectively. MDM2 was positive in all 11 patients with category IV tumors; CDK4 and p 16 were positive in 10 and eight patients, respectively. There was no difference of survival between the patients with category I, II and III and category IV. DDLPS without fatty components on MRI scans was mostly found. We recommend IHC staining to screen for DDLPS even if the tumors in STS cases have a non-fatty component.

Cystic Teratoma of the oral cavity

We present a rare case of sublingual cystic teratoma in the oral cavity with atypical magnetic resonance imaging (MRI) findings in a 4-year-old girl. The MRI demonstrated a well-marginated lesion in the oral cavity floor, high signal on T2-and iso signal on T1-weighted with thick wall and wall enhancement after intravenous contrast injection. The MRI findings were related to a congenital cyst of the oral cavity with a high proteinaceous material, suggesting an infected ranula. The cyst was surgically removed. The histopathological section of the excised specimen demonstrated a cyst line by epidermoid stratified squamous epithelium and ciliated respiratory mucosa, compatible with maturing cystic teratoma.

Magnetic resonance imaging pattern variability in dysferlinopathy.

The widespread use of magnetic resonance imaging (MRI) in the diagnosis of myopathies has made it possible to clarify the typical MRI pattern of dysferlinopathy. However, sufficient attention has not been given to the variability of MRI patterns in dysferlinopathy.Materials and methodsTwenty-five patients with the clinical manifestations of dysferlinopathy were examined. For all patients, creatine phosphokinase levels were measured and molecular genetics were examined. In two patients, immunohistochemical examinations of muscle biopsies were performed. MRI scanning was included T2 multi-slice multi-echo, T1 weighted, T2 weighted and Short Tau Inversion Recovery T2 weighted sequences. Quantitative and semi-quantitative evaluations of fatty replacement and swelling of the muscles were undertaken.ResultsVariability in the MRI patterns was lowest in the pelvis and leg muscles and highest in the thigh muscles. Three main types of MRI patterns were distinguished: posterior-dominant (80%), anterior-dominant (16%), and diffuse (4%). Among patients with the anterior-dominant pattern, the collagen-like variant (4%), proximal variant (4%) and pseudo-myositis (8%) were separately distinguished.ConclusionsAwareness of atypical MRI patterns in dysferlinopathy is important for increasing the efficiency of routine diagnostics and optimizing the search for causative gene mutations.

Neuroimaging findings of posterior reversible encephalopathy syndrome (PRES) following haematopoietic stem cell transplantation in paediatric recipients

BackgroundHaematopoietic stem cell transplantation (HSCT) is used worldwide in various malignant and nonmalignant childhood diseases, including haematologic, genetic, autoimmune and metabolic disorders, and is the only curative treatment for many of these illnesses. The survival rates of many childhood diseases have been increased due to HSCT treatment. However, associated complications are still important for management. Central nervous system (CNS) complications in paediatric HSCT recipients can be associated with high morbidity and significantly contribute to mortality. Posterior reversible encephalopathy syndrome (PRES) is one of the most common CNS complications in patients with neurological symptoms following HSCT. Magnetic resonance imaging (MRI) is the modality of choice and shows typical bilateral vasogenic oedema at the posterior parts of the cerebral hemispheres; however, various atypical imaging manifestations can also occur. In this study, we retrospectively examined CNS complications in our paediatric HSCT recipients with a focus on the typical and atypical neuroimaging manifestations of PRES following HSCT.MethodsWe retrospectively reviewed the medical records of 300 consecutive paediatric HSCT recipients from January 2014 to November 2018. A total of 130 paediatric HSCT recipients who experienced neurological signs and symptoms and were evaluated with neuroimaging studies following HSCT were enrolled in the study. The timing of CNS complications was defined according to immune status, including the pre-engraftment period (< 30 days after HSCT), the early postengraftment period (30–100 days after HSCT), and the late postengraftment period (> 100 days after HSCT), which were defined as phases 1, 2 and 3, respectively.ResultsOverall, 130 paediatric HSCT recipients experienced neurological signs and symptoms and therefore underwent neuroimaging examinations. Among these 130 patients, CNS complications were present in 23 patients (17.6%, 23/130), including 13 (56.5%) females and 10 (43.5%) males with a median age of 8.0 years (range, 8 months to 18.0 years). Among these 23 patients, 14 cases of PRES (60.9%), 5 (21.7%) cases of leukoencephalopathy, 3 cases of acute subdural haemorrhage (ASDH) (13%) and 1 (4.3%) case of fungal CNS infection were identified by neuroimaging. On MRI, typical parietooccipital vasogenic oedema was present in 78.5% of the PRES cases (11/14). The following atypical neuroimaging manifestations were observed: isolated involvement of the bilateral frontal lobes in 1 case, isolated cerebellar vermis involvement in 1 case, and isolated basal ganglia involvement in 1 case. Restricted diffusion associated with cytotoxic damage was demonstrated in 2 of 14 cases, one of which also showed subacute cytotoxic injury with ADC pseudonormalization.ConclusionPaediatric HSCT recipients presenting with CNS signs and symptoms should be evaluated by neuroimaging studies for timely diagnosis and early management. PRES is the most common CNS complication and may present with atypical MRI manifestations, which should not dissuade a PRES diagnosis in appropriate clinical settings.

Magnetic Resonance Imaging Evaluation of Spinal Infections

Background: The advantage of Magnetic resonance imaging include multiplanar capabilities and soft-tissue contrast resolution, which is superior to that of CT. Magnetic resonance (MR) imaging is a powerful diagnostic tool that can be used to help evaluate spinal infection and to help distinguish between an infection and other clinical conditions. Aim of the current study is to evaluate various spectrum and types of spinal infections, and discussing the role of MRI in diagnosing them and their characterization. Subjects &amp; Methods: This Hospital-based prospective study consists 30 patients with clinically suspected spinal infections and chronic non-resolving low backache referred to the department of Radiodiagnosis in a period of 2 years. Investigations include Complete blood count, ESR, sputum analysis for acid-fast bacilli and MRI of the spine. Results: 20 cases involved the lumbar spine, of which 12 were tubercular, seven were pyogenic, and one case was actinomycosis. In total 21 tubercular cases, 12 cases involved lumbar spine (57%), 8 cases affects the thoracic spine (38%), and 1 case involves the cervical spine (P = 0.562). the incidence of spondylodiscitis is common overall in the lumbar spine. 23.8% of tubercular and 12.5 %of pyogenic cases involved more than two vertebrae. T1 hypointensity is seen in 18 cases of tuberculosis (85%), 8 cases of pyogenic (75%), and 1 case of actinomycosis (100%) (P = 0.801). 4 cases showed preservation of disc height, among which three are tubercular (75%), and 1 was actinomycosis (25%). 85 % of tubercular and 100% of pyogenic cases showed disc narrowing. 81 % of tubercular and 100 % of pyogenic cases showed disc hyperintensity. Nine cases of tuberculosis (42.9%) and 3 cases of pyogenic (37.5 %) showed epidural abscess. 26 cases showed para vertebral extension of which 18 were tubercular (69.2 %), 7 were pyogenic (26.9 %) and 1 was actinomycosis (3.8 %). 94% of tubercular and 42 % of pyogenic abscesses showed a well-defined para spinal signal in cases of paraspinal extension. 15 of the 18(83%) tuberculosis, 3 of the 7 (42%)cases of pyogenic, and 1 case of actinomycosis showed subligamentous spread along more than three vertebrae. Heterogenous enhancement was noted in 12 of the 15 (80%) tubercular cases, 1 of the 3 (33%) pyogenic cases, and 1(100%) actinomycosis case. 71% tubercular cases and 2 of 8 (25%) cases showed predominant anterior 2/3rd involvement. Grade III or more (&gt;50%) vertebral destruction was seen in 16 tubercular (76%) and 2 pyogenic cases (25%). Six cases showed skip lesions of which 5were tubercular and 1 was pyogenic. 5 of the 21 (23.8%) tubercular and 1 of the 8 (12.5%) pyogenic cases showed skip lesions. Conclusion: Awareness of atypical MR imaging at early infectious spondylitis is important to avoid diagnostic delay and unnecessary other diagnostic procedures. Several non-infectious conditions may simulate the spinal infections. Hence It is helpful to be aware of these diseases and their MR imaging features. With these points in mind, MR imaging can be very beneficial to patients with spinal infection.

Preoperative Misdiagnosis of Malignant Mucosal Melanoma of the Nasal Septum by MRI.

Malignant sinonasal mucosal melanoma is a rare and aggressive neoplasm. As it shows nonspecific clinical symptoms, magnetic resonance imaging (MRI) is the most effective diagnostic tool. Before a mass is histopathologically confirmed, MRI is regarded as the optimal differential diagnostic procedure, especially in patients who present with a unilateral sinonasal cavity mass. However, we recently treated a patient who showed atypical MRI findings, resulting in a preoperative misdiagnosis of a vascular tumor. By pathologic examination, the patient was confirmed to have a malignant mucosal melanoma that originated from the nasal septum. This case demonstrates that unilateral nasal cavity masses that present with nonspecific symptoms, such as epistaxis, should be evaluated for possible malignant neoplasms, even if the mass has benign-looking characteristics in preoperative endoscopic findings and MRI images.

Atypical magnetic resonance imaging features and differential diagnosis of hepatocellular carcinoma

ObjectiveHepatocellular carcinoma (HCC) is the most common primary malignant tumor of the liver. We aimed to summarize and analyze the atypical magnetic resonance imaging (MRI) features of HCC to improve its diagnostic accuracy.MethodsWe retrospectively analyzed MRI data for 66 patients with HCC with atypical MRI features confirmed by operation and pathology.ResultsTwelve patients had high signals and 18 patients had significant decreases in opposed phase signals in T1WI plain scans. Nine patients had high signals and six patients had large cystic lesions in apparent diffusion coefficient images. Dynamic enhancement showed progressive enhancement in 15 patients, ring enhancement in three, irregular patchy enhancement in three, ‘nodule-in-nodule’ enhancement in six, delayed central patchy enhancement in six, delayed central ‘star-like aristate scars’ (T2WI revealed high signal intensity) in 21, and poor blood supply in three patients.ConclusionsMRI can make a clear diagnosis of typical HCC, and atypical cases can also be distinguished from other tumors or tumor-like lesions by MRI. The analysis of atypical signs may improve the diagnostic accuracy of MRI for HCC.

Childhood Posterior Reversible Encephalopathy Syndrome: Clinicoradiological Characteristics, Managements, and Outcome.

Posterior reversible encephalopathy syndrome (PRES) is a novel clinicoradiological syndrome characterized by convulsions, headache, altered mentality, and impaired vision, which are usually accompanied by hypertension. As its nomination, PRES is usually diagnosed according to the presence of typical neuroimage showing vasogenic edema predominately involving the posterior brain area. With the widespread utilization of magnetic resonance imaging (MRI), PRES is becoming more perceptible in different medical fields. Compared to adult cases, childhood PRES seems to have a broader clinical and neuroradiological spectrum. PRES can be associated with various underlying comorbidities, medication use, and therapeutic modalities in children with diverse neurological manifestations. Moreover, pediatric patients with PRES have a more significant propensity for atypical MRI findings beyond the typically posterior cerebral areas. The knowledge of typical and atypical presentations in children is essential to avoid misdiagnosing or missing PRES, which is a potentially treatable entity. Early supportive care is the mainstay of treatment, with particular attention to the treatment of hypertension with rigorous attention to all body systems. Prompt identification and symptom-directed management are imperative to achieve a reversible prognosis in childhood PRES. Future studies specially designed for the child population are required to determine potential outcome predictors, and further, to develop novel strategies of neuroprotection in childhood PRES.

Parenchymal central nervous system involvement in aggressive B-cell lymphoma: retrospective analysis of clinical and MRI features in a Chinese population

BackgroundSecondary central nervous system lymphoma (SCNSL) is defined as secondary central nervous system (CNS) involvement in patients with systemic lymphoma. It is considered a profoundly adverse complication with inferior clinical outcome. Parenchymal involvement in the CNS in aggressive B-cell lymphoma is not frequently seen and remains a diagnostic dilemma.MethodsIn our study, we retrospectively analyzed the clinical and magnetic resonance imaging (MRI) features of 26 parenchymal SCNSL patients. In addition, we compared MRI features of SCNSL and primary CNS lymphoma (PCNSL) patients after 1:1 propensity score matching. Also we presented two SCNSL cases with atypical MRI appearance.ResultsAmong SCNSL patients, the median CNS relapse time was 3 months, and multiple lesions were found in 76.9% of the cases. In PCNSL, this percentage was 42.3% (p = 0.011). None of the SCNSL patients and 23.1% of the PCNSL patients had solitary infratentorial lesions (p = 0.003).ConclusionsThe majority of parenchymal involvement occurred within the first year of systemic lymphoma, in which mostly cases presenting with multiple and supratentorial locations, unlike what was found in PCNSL.