Cerebral MR Imaging Research Articles

Doppler Ultrasound Flow Reversal in the Superior Sagittal Sinus to Detect Cerebral Venous Congestion in Vein of Galen Malformation.

Vein of Galen malformation is a rare congenital cerebrovascular malformation. In affected patients, increased cerebral venous pressure constitutes an important etiologic factor for the development of brain parenchymal damage. The aim of this study was to investigate the potential of serial cerebral venous Doppler measurements to detect and monitor increased cerebral venous pressure. This was a retrospective monocentric analysis of ultrasound examinations within the first 9 months of life in patients with vein of Galen malformation admitted at <28 days of life. Categorization of perfusion waveforms in the superficial cerebral sinus and veins into 6 patterns was based on antero- and retrograde flow components. We performed an analysis of flow profiles across time and correlation with disease severity, clinical interventions, and congestion damage on cerebral MR imaging. The study included 44 Doppler ultrasound examinations of the superior sagittal sinus and 36 examinations of the cortical veins from 7 patients. Doppler flow profiles before interventional therapy correlated with disease severity determined by the Bicêtre Neonatal Evaluation Score (Spearman ρ = -0.97, P = < .001). At this time, 4 of 7 patients (57.1%) showed a retrograde flow component in the superior sagittal sinus, whereas after embolization, none of the 6 treated patients presented with a retrograde flow component. Only patients with a high retrograde flow component (equal or more than one-third retrograde flow, n = 2) showed severe venous congestion damage on cerebral MR imaging. Flow profiles in the superficial cerebral sinus and veins appear to be a useful tool to noninvasively detect and monitor cerebral venous congestion in vein of Galen malformation.

Immune Checkpoint Inhibitor-Induced Cerebral Pseudoprogression: Patterns and Categorization.

BackgroundThe inclusion of immune checkpoint inhibitors (ICIs) in therapeutic algorithms has led to significant survival benefits in patients with various metastatic cancers. Concurrently, an increasing number of neurological immune related adverse events (IRAE) has been observed. In this retrospective analysis, we examine the ICI-induced incidence of cerebral pseudoprogression and propose a classification system.MethodsWe screened our hospital information system to identify patients with any in-house ICI treatment for any tumor disease during the years 2007-2019. All patients with cerebral MR imaging (cMRI) of sufficient diagnostic quality were included. cMRIs were retrospectively analyzed according to immunotherapy response assessment for neuro-oncology (iRANO) criteria.ResultsWe identified 12 cases of cerebral pseudoprogression in 123 patients treated with ICIs and sufficient MRI. These patients were receiving ICI therapy for lung cancer (n=5), malignant melanoma (n=4), glioblastoma (n=1), hepatocellular carcinoma (n=1) or lymphoma (n=1) when cerebral pseudoprogression was detected. Median time from the start of ICI treatment to pseudoprogression was 5 months. All but one patient developed neurological symptoms. Three different patterns of cerebral pseudoprogression could be distinguished: new or increasing contrast-enhancing lesions, new or increasing T2 predominant lesions and cerebral vasculitis type pattern.ConclusionCerebral pseudoprogression followed three distinct patterns and was detectable in 3.2% of all patients during ICI treatment and in 9.75% of the patients with sufficient brain imaging follow up. The fact that all but one of the affected patients developed neurological symptoms, which would be classified as progressive disease according to iRANO criteria, mandates vigilance in the diagnosis and treatment of ICI-induced cerebral lesions.

Superficial Siderosis and Microbleed Restricted in Cortex Might Be Correlated to Atrophy and Cognitive Decline in Sneddon's Syndrome.

Objective: Sneddon's syndrome is a rare non-inflammatory arteriopathy affecting small and medium-sized arteries, characterized by a generalized livedo reticularis and recurrent transient ischemic attack or ischemic stroke. Hemorrhagic stroke was reported in limited cases, but microbleeds and superficial siderosis were rarely issued. We aimed to investigate the hemorrhagic imaging features of Sneddon's syndrome and explore the possible mechanism and clinical relevance.Methods: Clinical data and cerebral MR imaging including T2* sequence of seven consecutive patients with Sneddon's syndrome were reviewed.Results: The most common neurological manifestations were cognitive impairment and stroke attack (71.4%), followed by seizures and movement disorder (28.6%). Cerebral microbleeds were detected in six patients on T2* sequence, all of them presented with cortical microbleeds, only one of them with microbleeds in basal ganglion. More than five microbleeds were observed in four of these six patients. The majority of the microbleeds were predominantly cortical restricted and especially located in the cortical watersheds. Multiple superficial siderosis were identified mainly involving cortical watersheds in five cases. Significant cerebral atrophy with prominent secondary white matter hyperintensities in bilateral cortical watersheds were also observed. Abnormal tortuous and multiple focal occlusion of bilateral distal MCA were shown in one patient by DSA. No stenosis of proximal segment of cerebral arteries was detected in all the patients.Conclusions: This is the first report illustrating abundant cortical microbleeds and superficial siderosis mainly involved the anterior and posterior cortical watersheds in Sneddon's syndrome. The surprisingly identical topographic distribution of hemorrhagic lesions and the obvious atrophy suggest cerebral atrophy might be secondary to the microangiopathy related hemorrhagic lesions and further contribute to the neurological deficit, especially the early cognitive decline in Sneddon syndrome.

Introduction of Ultra-High-Field MR Imaging in Infants: Preparations and Feasibility.

Cerebral MR imaging in infants is usually performed with a field strength of up to 3T. In adults, a growing number of studies have shown added diagnostic value of 7T MR imaging. 7T MR imaging might be of additional value in infants with unexplained seizures, for example. The aim of this study was to investigate the feasibility of 7T MR imaging in infants. We provide information about the safety preparations and show the first MR images of infants at 7T. Specific absorption rate levels during 7T were simulated in Sim4life using infant and adult models. A newly developed acoustic hood was used to guarantee hearing protection. Acoustic noise damping of this hood was measured and compared with the 3T Nordell hood and no hood. In this prospective pilot study, clinically stable infants, between term-equivalent age and the corrected age of 3 months, underwent 7T MR imaging immediately after their standard 3T MR imaging. The 7T scan protocols were developed and optimized while scanning this cohort. Global and peak specific absorption rate levels in the infant model in the centered position and 50-mm feet direction did not exceed the levels in the adult model. Hearing protection was guaranteed with the new hood. Twelve infants were scanned. No MR imaging-related adverse events occurred. It was feasible to obtain good-quality imaging at 7T for MRA, MRV, SWI, single-shot T2WI, and MR spectroscopy. T1WI had lower quality at 7T. 7T MR imaging is feasible in infants, and good-quality scans could be obtained.

Abstract WP476: Remarkable Hemorrhagic Imaging Manifestations Might Be Responsible for the Prominent Atrophy and Cognitive Decline in Sneddon Syndrome

Objective: Sneddon syndrome is a rare non-inflammatory arteriopathy affecting small and medium-sized arteries, characterized by a generalized livedo reticularis and recurrent ischemic stroke. Hemorrhagic stroke was reported in limited cases, but microbleeds and superficial siderosis were rarely issued, which might be underdiagnosed due to the limitation of technique. We aimed to investigate the hemorrhagic imaging features of Sneddon syndrome and explore the possible mechanism and clinical relevance. Methods: Clinical data and cerebral MR imaging including T2* sequence of 6 consecutive patients with Sneddon syndrome were reviewed. Results: The most common neurological manifestations were cognitive impairment and stroke attack(66.7%), followed by seizures(33.3%) and movement disorder(16.7%). Cerebral microbleeds were detected in all the patients on T2* sequence,four of whom presented more than 5 microbleeds.The majority of the microbleeds were predominantly cortical restricted and especially located in the cortical watersheds. Multiple superficial siderosis were identified and mainly involved cortical watersheds in 5 cases. Significant cerebral atrophy with prominent secondary white matter hyperintensities in bilateral cortical watersheds were also observed. Abnormal tortuous and multiple focal occlusion of bilateral distal MCA were shown in 1 patient by DSA. No stenosis of proximal segment of cerebral arteries was detected in all the patients. Conclusions: This is the first report illustrating abundant cortical microbleeds and superficial siderosis mainly involved the anterior and posterior cortical watersheds in Sneddon syndrome. The surprisingly identical topographic distribution of hemorrhagic lesions and the corresponding obvious atrophy suggest cerebral atrophy might be secondary to the microangiopathy related hemorrhagic lesions and further contribute to the neurological deficit, especially the early cognitive decline in Sneddon syndrome,although further investigation is needed to elucidate the precise underlying pathogenesis. These highlight cortical microbleeds and superficial siderosis located in cortical watershed and the secondary atrophy in youth might be highly indicative of Sneddon syndrome.

RARE COMPLICATION OF A RARE DISEASE

SESSION TITLE: Pulmonary Pathology II SESSION TYPE: Med Student/Res Case Report PRESENTED ON: 10/21/2019 3:15 PM - 4:15 PM INTRODUCTION: Primary pulmonary lymphoma (PPL) comprises of only 1% of pulmonary malignancies and has been described with systemic autoimmune diseases. It may be associated with a fatal disease known as intravascular lymphoma which is extremely rare and can lead to a diagnostic dilemma. CASE PRESENTATION: 58 year old female with history of Sjögren’s syndrome presented to the pulmonology clinic with complaints of shortness of breath cough and low grade fever for 2 weeks. She was vitally stable with bronchial breath sounds at the right lower lung zone. Chest X-ray showed right middle lobe collapse. The CT scan chest after 2 weeks of conservative treatment showed soft tissue density in the bronchus intermedius (BI). Bronchoscopy revealed pinkish lesion in BI. The histopathology showed high grade B cell Non-Hodgkin's lymphoma. The patient was started on chemotherapy with R-CHOP (rituximab, cyclophosphamide, doxorubicin and prednisolone). After third cycle of chemotherapy she was admitted with fever and bodyaches. She became increasingly somnolent and dropped her GCS requiring intubation. The MRI brain showed diffusely scattered foci of signal dropout on SWI throughout the brain, predominantly in the corpus callosum and diffuse multifocal areas of diffusion restriction in periventricular and subcortical white matter. Lumbar puncture and EEG were negative. Brain biopsy was not attempted considering her clinical instability. She was treated with pulse steroids leading to improvement in GCS. A follow up MRI after pulse therapy showed interval improvement of the brain lesions. DISCUSSION: We believe that our case describes the presentation of a malignancy which progressed to develop a rare complication known as Intravascular lymphoma (IVL); it is a subtype of extranodal large B-cell lymphoma which spreads in angiotropic pattern to virtually any organ of the body, brain and skin being the most common sites. The gold standard of diagnosis is histological evidence of intravascular invasion but studies are being reported to identify noninvasive modalities of diagnosis of IVL (1). Recent literature reports various neuroimaging findings of IVL like multiple foci of high signal intensity in the deep white matter, infarct like changes and intracranial mass (2). Treatment of IVL is based on the RCHOP regimen, however prognosis is poor (3). The responsiveness to steroid therapy supports the diagnosis of IVL. CONCLUSIONS: A high index of suspicion is required to diagnose IVL in patients with Non-Hodgkins who present with neurological symptoms. An emerging evidence supports the use of neuroimaging in diagnosis of IVL in patients without tissue diagnosis. Reference #1: Shimada K, Kinoshita T, Naoe T, Nakamura S. Presentation and management of intravascular large B-cell lymphoma. The lancet oncology. 2009 Sep 1;10(9):895-902 Reference #2: Yamamoto A, Kikuchi Y, Homma K, O'uchi T, Furui S. Characteristics of intravascular large B-cell lymphoma on cerebral MR imaging. American Journal of Neuroradiology. 2012 Feb 1;33(2):292-6 Reference #3: Baehring JM, Longtine J, Hochberg FH. A new approach to the diagnosis and treatment of intravascular lymphoma. Journal of neuro-oncology. 2003 Feb 1;61(3):237-48 DISCLOSURES: no disclosure on file for Arsalan Ahmad; No relevant relationships by Hasaan Omar, source=Web Response No relevant relationships by Aqusa Zahid, source=Web Response No relevant relationships by Ali Zubairi, source=Web Response

GJA1 Variants Cause Spastic Paraplegia Associated with Cerebral Hypomyelination.

Oculodentodigital dysplasia is an autosomal dominant disorder due to GJA1 variants characterized by dysmorphic features. Neurologic symptoms have been described in some patients but without a clear neuroimaging pattern. To understand the pathophysiology underlying neurologic deficits in oculodentodigital dysplasia, we studied 8 consecutive patients presenting with hereditary spastic paraplegia due to GJA1 variants. Clinical disease severity was highly variable. Cerebral MR imaging revealed variable white matter abnormalities, consistent with a hypomyelination pattern, and bilateral hypointense signal of the basal ganglia on T2-weighted images and/or magnetic susceptibility sequences, as seen in neurodegeneration with brain iron accumulation diseases. Patients with the more prominent basal ganglia abnormalities were the most disabled ones. This study suggests that GJA1-related hereditary spastic paraplegia is a complex neurodegenerative disease affecting both the myelin and the basal ganglia. GJA1 variants should be considered in patients with hereditary spastic paraplegia presenting with brain hypomyelination, especially if associated with neurodegeneration and a brain iron accumulation pattern.

Complete Recovery of Perfusion Abnormalities in a Cardiac Arrest Patient Treated with Hypothermia: Results of Cerebral Perfusion MR Imaging

Complete Recovery of Perfusion Abnormalities in a Cardiac Arrest Patient Treated with Hypothermia: Results of Cerebral Perfusion MR Imaging

Burden and Risk of Neurological and Cognitive Impairment in Pediatric Sickle Cell Anemia in Uganda (BRAIN SAFE): Interim Overall Results

Sickle Cell Anemia (SCA) is highly prevalent in sub-Saharan Africa (SSA). In Uganda, approximately 20,000 children are born with SCA annually (Ndeezi G, 2016). Sickle brain vasculopathy causes both overt strokes and clinically “silent infarcts,” affecting neurological and cognitive function (DeBaun MR, 2012). Incidence of strokes has markedly decreased through standardized preventative measures. Study objectives are to determine the age-related spectrum and burden of brain injury associated with SCA in Ugandan children, determine predisposing risk factors and build capacity to support interventions for stroke prevention. Here we present preliminary results.Methods: BRAIN SAFE is a cross-sectional study of a random sample of 250 children with SCA, ages 1-12 years, who receive care at the Mulago Hospital SCD clinic in Kampala.Potential participants were randomly selected from the clinic roster. Study exclusion criteria: hemoglobinopathy other than HbSS or HbS B0 thalassemia, age >12, acute illness, Hb <6.0gm/dl, recent transfusion, participation in another clinical study.Stroke history and examination: were performed using the pediatric NIH Stroke Scale. Psychometric testing: Age-appropriate KABC-II, TOVA, BRIEF and Mullen testing were performed by skilled testers using validated versions in English or the predominant local language.Transcranial doppler ultrasounds (TCDs) were performed (with good inter-operator reliability) by two study staff, both health professionals. They had been trained by a U.S.-based “STOP” trial TCD research nurse and a co-investigator who had TCD training in the U.S. The latter also performed standardized readings (Adams RJ, 1998). Quality assurance for TCD readings was provided by an independent stroke neurologist.Brain Magnetic imaging (MRI/MRA): Using a single 1.5T scanner, a subset of subjects enriched for a history of stroke, abnormal neurological exam and/or cognitive testing. Two radiologists performed clinical reads. An independent neuroradiologist assessed sickle vasculopathy, per “SWiTCH” protocol (Helton KJ, 2014), blinded to clinical and radiological data.Primary and secondary stroke prevention : Subjects with persistently non-normal TCDs on repeat testing or vasculopathy on MRI/MRAswill be offered hydroxyurea .Results: Of the 248 participants screened in the 1st funding year, 233 were enrolled (mean age 5.62 years (range 1-12). Study exclusions due to age >12, acute illness, severe anemia, recent transfusion or participation in another study.History and neurological exam : Overall, 7 of 233 had history consistent with a stroke, and an abnormal neurological exam, 5 had a history consistent with stroke but a normal neurological exam, 6 had abnormal neurological findings but no history of stroke (total abnormal 18/233, 7.7%).Psychometrics : To date, cognitive test data results have been performed on 80 children; 30 (37.5%) were impaired with varying severity. (Full reports to follow.)TCDs : A total of 224 non-imaging TCDs have been performed. Using standard criteria, 190 were normal, 4 abnormal (1.8%), and 30 conditional (13.4%). Repeat TCDs have been performed on 13 of those with non-normal reads and so far, 2 were abnormal, 6 conditional, 4 normal,1 had difficult windows.MRI/MRAs: A subset of 29 subjects were selected with more clinical and/or historical stroke pathology (N= 25, 86%) and have undergone MR imaging to date (see Table). Mean age was 7.1 years (range 3-12); male: 55%. Of 26 with clinical radiological reads, 16 / 26 (61.5%) were abnormal. To date, scans from 12 subjects have had SCD vascular reads: 2 had no vasculopathy; 10 were abnormal: 6 with infarcts and arterial stenoses, 3 with infarcts only, 1 with bilateral stenoses only.Conclusions: BRAIN SAFE, a Kampala-based cross-sectional study, has already enrolled and completed a large proportion of study procedures. Considerable brain pathology has been identified in all aspects tested, with high prevalence of abnormal history or physical findings, abnormal psychometrics, abnormal cerebral blood flow and/or brain MR imaging. Completion of enrollment and testing for the target sample will provide baseline data for longitudinal assessment and intervention. Building research capacity for faculty and trainees is ongoing.Acknowledgments: 1R21HD089791 (PIs: Idro, Green) and Latanya Bowman, RN, Augusta University Sickle Cell Center. [Display omitted] DisclosuresNo relevant conflicts of interest to declare.

Lymphomatosis cerebri: a rare variant of primary central nervous system lymphoma and MR imaging features

BackgroundLymphomatosis cerebri (LC) is a rare variant of primary central nervous system lymphoma (PCNSL), characterized by diffuse infiltration without the formation of a discrete mass. The diagnosis of LC is a challenge because the imaging findings are atypical for lymphoma. The purpose of present study is to investigate MRI characteristics and clinical features of LC and potentially facilitate an early and accurate diagnosis of this often-missed disease.MethodsSeven patients (average 44 years, 19–58 years) with LC proved basing on MRI and histology were retrospectively reviewed the clinical data and cerebral MR imaging findings.ResultsThe common presenting symptoms were cognitive decline, behavioral disturbance, gait disturbance. All patients had both deep and lobar lesion distribution, and two of them had infratentorial involvement. Lack of contrast enhancement and subtle patchy enhanced pattern were observed in two and three patients, respectively. The remaining two patients presented multiple patchy enhancement. Most of the lesions were slightly hyperintense to normal brain on DWI as well as hyperintense on ADC maps. Three patients presented a pattern of marked decrease of NAA/Cr, increase of Cho/Cr, and two of the three cases showed increased Lip/Cr and Lac/Cr on MRS.ConclusionsWe conclude that diffuse bilateral lesions especially in deep and lobar region including white and gray matter, without enhancement or with patchy enhancement, marked decrease of NAA/Cr and increase of Cho/Cr, and increased Lip/Cr and Lac/Cr are suggestive of LC. Prompt recognition of these imaging patterns may lead to early diagnosis of LC and brain biopsy with improved prognosis.

What Imaging for Cerebral Complications of Infective Endocarditis?

Infective endocarditis (IE) is a serious condition with in-hospital mortality rates of 15-20% and one-year mortality approaching 40%. [ [1] Murdoch D.R. et al. Clinical Presentation, Etiology and Outcome of Infective Endocarditis in the 21st Century: The International Collaboration on Endocarditis-Prospective Cohort Study. Archives of Internal Medicine. 2009; 169.5 (PMC. Web. 23 Aug. 2015): 463-473 Crossref Scopus (1482) Google Scholar ] Early diagnosis and treatment reduces the incidence of septic embolism and mortality. [ [2] Erba P.A. Conti U. Lazzeri E. et al. Added value of 99mTc-HMPAO–labeled leukocyte SPECT/CT in the characterization and management of patients with infectious endocarditis. J Nucl Med. 2012; 53: 1235-1243 Crossref PubMed Scopus (147) Google Scholar ] We reviewed cerebral imaging studies performed for IE and the rate of clinical findings over a 10-year period to determine if there was a significant difference in complications found when using MR over CT. Cerebral imaging requests and reports at our institution from 2003-2013 were searched for IE related complications. Clinical cerebral complications were identified in 62 of the 161 patients scanned (38.5%). Using CT or CTA cerebral complications were found in 42 of 132 patients (31.8%), and 36 of 61 patients (59%) using MRI or MRA. Over a 10-year period, cerebral MR imaging identified significantly more complications of IE than CT (63.5% v 39.6%, p<0.01), with a greater proportion of infarcts being discovered (75% v 46%). Early detection of asymptomatic cerebrovascular complications through the use of systematic cerebral MR in suspected IE cases may be the prompt for more aggressive surgical management.

Quantitative measurement of cerebral oxygen metabolism using asymmetric spin echo version of echo planar imaging sequence in an animal model of ischimia

Objective To assess whether asymmetric spin echo version of echo planar imaging (ASE EPI) sequence can reflect cerebral oxygen metabolism by means of the changes in oxygen extraction fraction values before and after surgical operations in the canine model of ischimia. Methods A total of 12 healthy crossbreed dogs were enrolled in this study. All canines underwent cerebral MR imaging including coronal T2WI, DWI, MRA, ASE EPI and 3D PCASL. The bilateral carotid arteries (CA) were separated by surgical operations. The bilateral CA were ligated in 6 dogs, and the other 6 dogs had embolization in ligated bilateral CA. The cerebral MR imaging with the above protocol was repeated at 1 hour after surgical operation for each dog. All dogs were executed when they finished the MR examinations. Then the whole brains of the dogs were taken out for cutting coronal sections and 2, 3, 5-triphenyltetrazolium chloride (TTC) staining. The ASE EPI data were processed by the Functool software in the workstation to generate OEF maps. For measuring the OEF values before and 1 hour after surgical operations, one and the same region of interest (ROI) was respectively placed in the left and right hemispheres on the OEF maps for each dog. 3D PCASL data were processed by the Functool software in the workstation to yield CBF maps. The method for measuring the CBF values before and 1 hour after surgical operations on CBF maps was same as that for measuring on OEF maps. The changes of measurements before and after surgical operations were compared between the dogs with ligated bilateral CA and the dogs with embolization in ligated bilateral CA by using an independent samples t test. The measurements before and after surgical operations were respectively compared in the dogs with ligated bilateral CA and the dogs with embolization in ligated bilateral CA by using a paired t-test. The cutting slices with TTC staining were analysed for determining ischimia. Results The CBF values of the dogs with ligated bilateral CA were (59.81±23.59) and (38.56±12.98) ml/(min·100 g) before and after surgical operations, respectively. The CBF values of the dogs with embolization in ligated bilateral CA were (58.94±18.35) and (28.01±11.41) ml/(min·100 g) before and after surgical operations, respectively. The CBF values were significantly lower before surgical operations than after surgical operations in the dogs with ligated bilateral CA and the dogs with embolization in ligated bilateral CA, respectively (t=8.92 and 13.42, respectively; P=0.00, respectively). The CBF values were decreased more significantly in the dogs with embolization in ligated bilateral CA than in the dogs with ligated bilateral CA (t=2.92, P=0.00). The OEF values of the dogs with ligated bilateral CA were 0.29±0.02 and 0.32±0.06 before and after surgical operations, respectively. The OEF values of the dogs with embolization in ligated bilateral CA were 0.29±0.02 and 0.35±0.06 before and after surgical operations, respectively. The OEF values were significantly higher before surgical operations than after surgical operations in the dogs with ligated bilateral CA and the dogs with embolization in ligated bilateral CA, respectively (t=-7.21 and -4.43, respectively; P=0.00, respectively). The OEF values were increased more significantly in the dogs with embolization in ligated bilateral CA than in the dogs with ligated bilateral CA (t=2.18, P=0.03). The pathological results showed that the dogs with embolization in ligated bilateral CA had swollen cortex with focal infarction which was matched with the hyperintensity areas on the OEF and DWI images. However, the dogs with ligated bilateral CA only had swollen cortex whereas didn't have focal infarction. Conclusions ASE EPI sequence can reliably reflect cerebral oxygen metabolism in ischemia. This sequence has an important role for assessing hemodynamic state in patients with cerebral vascular diseases. Key words: Brain ischemia; Magnetic resonance imaging; Animal experimentation

Paediatric patients with sudden vision impairment - An overview of MRI findings.

Sudden visual impairment in children occurs sporadically but, when present, needs urgent attention. Optimal management strategies and timely recognition are required. Often psychogenic disorders are the cause in school-age children; however, this is a diagnosis of exclusion. Therefore, MRI plays an important role in ruling out pathology along the optic pathways or helping with the diagnosis of underlying life threatening diseases, such as hydrocephalus or intracranial mass. The purpose of this study was first to evaluate non-traumatic (tumoural and non-tumoural) causes of acute vision impairment; and, second, to assess whether conventional cerebral and orbital MR imaging is helpful for children with sudden visual impairment. We retrospectively analysed the MRI scans and clinical findings of 95 children (47 male, 48 female; median age: 12.5 years, range: from 2 to 17 years) who presented symptoms of monocular or bilateral acute vision impairment. Patients with acute visual impairment were usually older than 7 years. In 36% of the patients a correlation between the MRI findings and the clinical symptoms was found. The most common causes of visual impairment were: infectious diseases (16%), migraine (12%), autoimmune diseases (11%), optic nerve neuritis with unknown aetiology (8%), neoplasms (8%), idiopathic intracranial hypertension (5%) and orthostatic hypotension (4%). Still, in 23% of the patients the cause remained unclear. Acute vision impairment is frequently caused by infectious diseases, migraine, autoimmune diseases or tumours in children. MRI is highly recommended, especially in the case of children younger than 5 years of whom clinical assessment can be difficult.

The Protective Effect of Human Umbilical Cord Blood CD34+ Cells and Estradiol against Focal Cerebral Ischemia in Female Ovariectomized Rat: Cerebral MR Imaging and Immunohistochemical Study

Human umbilical cord blood derived CD34+ stem cells are reported to mediate therapeutic effects in stroke animal models. Estrogen was known to protect against ischemic injury. The present study wished to investigate whether the protective effect of CD34+ cells against ischemic injury can be reinforced with complemental estradiol treatment in female ovariectomized rat and its possible mechanism. Experiment 1 was to determine the best optimal timing of CD34+ cell treatment for the neuroprotective effect after 60-min middle cerebral artery occlusion (MCAO). Experiment 2 was to evaluate the adjuvant effect of 17β-estradiol on CD34+ cell neuroprotection after MCAO. Experiment 1 showed intravenous infusion with CD34+ cells before MCAO (pre-treatment) caused less infarction size than those infused after MCAO (post-treatment) on 7T magnetic resonance T2-weighted images. Experiment 2 revealed infarction size was most significantly reduced after CD34+ + estradiol pre-treatment. When compared with no treatment group, CD34+ + estradiol pre-treatment showed significantly less ADC reduction at 2 h and 2 d, less CBF reduction at 2 h and less hyperperfusion at 2 d. The immunoreactivity of c-Fos, c-Jun and GFAP was attenuated, and BDNF showed significant recovery from 2 h to 2 d after MCAO, especially after CD34+ + estradiol pre-treatment. The present study suggests pre-treatment with CD34+ cells with complemental estradiol can be most protective against ischemic injury, which may act through stabilization of cerebral hemodynamics and normalization of the expressions of immediate early genes and BDNF.

47 patients with FLNA associated periventricular nodular heterotopia.

BackgroundHeterozygous loss of function mutations within the Filamin A gene in Xq28 are the most frequent cause of bilateral neuronal periventricular nodular heterotopia (PVNH). Most affected females are reported to initially present with difficult to treat seizures at variable age of onset. Psychomotor development and cognition may be normal or mildly to moderately impaired. Distinct associated extracerebral findings have been observed and may help to establish the diagnosis including patent ductus arteriosus Botalli, progressive dystrophic cardiac valve disease and aortic dissection, chronic obstructive lung disease or chronic constipation. Genotype-phenotype correlations could not yet be established.MethodsSanger sequencing and MLPA was performed for a large cohort of 47 patients with Filamin A associated PVNH (age range 1 to 65 years). For 34 patients more detailed clinical information was available from a structured questionnaire and medical charts on family history, development, epileptologic findings, neurological examination, cognition and associated clinical findings. Available detailed cerebral MR imaging was assessed for 20 patients.ResultsThirty-nine different FLNA mutations were observed, they are mainly truncating (37/39) and distributed throughout the entire coding region. No obvious correlation between the number and extend of PVNH and the severity of the individual clinical manifestation was observed. 10 of the mutation carriers so far are without seizures at a median age of 19.7 years. 22 of 24 patients with available educational data were able to attend regular school and obtain professional education according to age.ConclusionsWe report the clinical and mutation spectrum as well as MR imaging for a large cohort of 47 patients with Filamin A associated PVNH including two adult males. Our data are reassuring in regard to psychomotor and cognitive development, which is within normal range for the majority of patients. However, a concerning median diagnostic latency of 17 to 20 years was noted between seizure onset and the genetic diagnosis, intensely delaying appropriate medical surveillance for potentially life threatening cardiovascular complications as well as genetic risk assessment and counseling prior to family planning for this X-linked dominant inherited disorder with high perinatal lethality in hemizygous males.

Evaluation of 4D vascular flow and tissue perfusion in cerebral arteriovenous malformations: influence of Spetzler-Martin grade, clinical presentation, and AVM risk factors.

The role of intracranial hemodynamics in the pathophysiology and risk stratification of brain AVMs remains poorly understood. The purpose of this study was to assess the influence of Spetzler-Martin grade, clinical history, and risk factors on vascular flow and tissue perfusion in cerebral AVMs. 4D flow and perfusion MR imaging was performed in 17 patients with AVMs. Peak velocity and blood flow were quantified in AVM feeding and contralateral arteries, draining veins, and the straight sinus. Regional perfusion ratios (CBF, CBV, and MTT) were calculated between affected and nonaffected hemispheres. Regarding flow parameters, high-grade AVMs (Spetzler-Martin grade of >2) demonstrated significantly increased peak velocity and blood flow in the major feeding arteries (P < .001 and P = .004) and straight sinus (P = .003 and P = .012) and increased venous draining flow (P = .001). The Spetzler-Martin grade significantly correlated with cumulative feeding artery flow (r = 0.85, P < .001) and draining vein flow (r = 0.80, P < .001). Regarding perfusion parameters, perinidal CBF and CBV ratios were significantly lower (P < .001) compared with the remote ratios and correlated negatively with cumulative feeding artery flow (r = -0.60, P = .014 and r = -0.55, P = .026) and draining vein flow (r = -0.60, P = .013 and r = -0.56, P = .025). Multiple regression analysis revealed no significant association of AVM flow or perfusion parameters with clinical presentation (rupture and seizure history) and AVM risk factors. Macrovascular flow was significantly associated with increasing Spetzler-Martin grade and correlated with perinidal microvascular perfusion in cerebral AVMs. Future longitudinal studies are needed to evaluate the potential of comprehensive cerebral flow and perfusion MR imaging for AVM risk stratification.

Cerebral relaxation times from postmortem MR imaging of adults.

We measured T1 and T2 values of cerebral postmortem magnetic resonance (PMMR) imaging and compared the data of cadavers with that of living human subjects. We performed PMMR imaging of the brains of 30 adults (22 men, 8 women; mean age, 58.2 years) whose deaths were for reasons other than brain injury or disease at a mean of 29.4 hours after death. Before imaging, the bodies were kept in cold storage at 4°C (mean rectal temperature, 15.6°C). We measured T1 and T2 values in the brain bilaterally at 5 sites (bilateral caudate nucleus, putamen, thalamus and gray matter and white matter of the frontal lobe) and compared the data of PMMR imaging with that from MR imaging of the corresponding sites in 24 healthy volunteers (9 men, 15 women; mean age, 51.8 years). We also investigated the influence of body temperature on T1 and T2 values. Compared with MR imaging findings in the living subjects, PMMR imaging showed significantly shorter T1 values in the caudate nucleus, putamen, thalamus and gray matter and white matter of the frontal lobe and significantly longer T2 values in the gray matter and white matter of the frontal lobe; T2 values in the caudate nucleus, putamen, and thalamus showed no such differences. T1 values correlated significantly with body temperature in all 5 brain sites measured, but T2 values did not. Compared with findings of cerebral MR imaging in living adult subjects, those of PMMR imaging tended to demonstrate shorter T1 values and longer T2 values. We attribute this to increased water content of tissue, reduced pH, and reduced body temperature after death.

Cerebral Veins-Why Functional MR Imaging is Worth the Trouble

The incidence of multiple sclerosis in North America is approximately 5/100,000, and the peak of onset is 30 years of age. Hence, MS is one of the most frequent chronic neurologic diseases and the leading cause of disability in young and middle-aged individuals in the developed world.[1][1]

Impact of bubble size in a rat model of cerebral air microembolization

BackgroundCerebral air microembolization (CAM) is a frequent side effect of diagnostic or therapeutic interventions. Besides reduction of the amount of bubbles, filter systems in the clinical setting may also lead to a dispersion of large gas bubbles and therefore to an increase of the gas–liquid-endothelium interface. We evaluated the production and application of different strictly defined bubble diameters in a rat model of CAM and assessed functional outcome and infarct volumes in relation to the bubble diameter.MethodsGas emboli of defined number and diameter were injected into the carotid artery of rats. Group I (n = 7) received 1800 air bubbles with a diameter of 45 μm, group II (n = 7) 40 bubbles of 160 μm, controls (n = 6) saline without gas bubbles; group I and II yielded the same total injection volume of air with 86 nl. Functional outcome was assessed at baseline, after 4 h and 24 h following cerebral MR imaging and infarct size calculation.ResultsComputer-aided evaluation of bubble diameters showed high constancy (group I: 45.83 μm ± 2.79; group II: 159 μm ± 1.26). Animals in group I and II suffered cerebral ischemia and clinical deterioration without significant difference. Infarct sizes did not differ significantly between the two groups (p = 0.931 u-test).ConclusionsWe present further development of a new method, which allows reliable and controlled CAM with different bubble diameters, producing neurological deficits due to unilateral cerebral damage. Our findings could not display a strong dependency of stroke frequency and severity on bubble diameter.

Conventional and advanced imaging in neuromyelitis optica.

Myelitis and optic neuritis are prototypic clinical presentations of both multiple sclerosis and neuromyelitis optica. Once considered a subtype of multiple sclerosis, neuromyelitis optica, is now known to have a discrete pathogenesis in which antibodies to the water channel, aquaporin 4, play a critical role. Timely differentiation of neuromyelitis optica from MS is imperative, determining both prognosis and treatment strategy. Early, aggressive immunosuppression is required to prevent the accrual of severe disability in neuromyelitis optica; conversely, MS-specific therapies may exacerbate the disease. The diagnosis of neuromyelitis optica requires the integration of clinical, MR imaging, and laboratory data, but current criteria are insensitive and exclude patients with limited clinical syndromes. Failure to recognize the expanding spectrum of cerebral MR imaging patterns associated with aquaporin 4 antibody seropositivity adds to diagnostic uncertainty in some patients. We present the state of the art in conventional and nonconventional MR imaging in neuromyelitis optica and review the place of neuroimaging in the diagnosis, management, and research of the condition.