Identifying responders to vagus nerve stimulation based on microstructural features of thalamocortical tracts in drug-resistant epilepsy.

The mechanisms of action of Vagus Nerve Stimulation (VNS) and the biological prerequisites to respond to the treatment are currently under investigation. It is hypothesized that thalamocortical tracts play a central role in the antiseizure effects of VNS by disrupting the genesis of pathological activity in the brain. This pilot study explored whether in vivo microstructural features of thalamocortical tracts may differentiate Drug-Resistant Epilepsy (DRE) patients responding and not responding to VNS treatment. Eighteen patients with DRE (37.11 â€‹± â€‹10.13 years, 10 females), including 11 responders or partial responders and 7 non-responders to VNS, were recruited for this high-gradient multi-shell diffusion Magnetic Resonance Imaging (MRI) study. Using Diffusion Tensor Imaging (DTI) and multi-compartment models - Neurite Orientation Dispersion and Density Imaging (NODDI) and Microstructure Fingerprinting (MF), we extracted microstructural features in 12 subsegments of thalamocortical tracts. These characteristics were compared between responders/partial responders and non-responders. Subsequently, a Support Vector Machine (SVM) classifier was built, incorporating microstructural features and 12 clinical covariates (including age, sex, duration of VNS therapy, number of antiseizure medications, benzodiazepine intake, epilepsy duration, epilepsy onset age, epilepsy type - focal or generalized, presence of an epileptic syndrome - no syndrome or Lennox-Gastaut syndrome, etiology of epilepsy - structural, genetic, viral, or unknown, history of brain surgery, and presence of a brain lesion detected on structural MRI images). Multiple diffusion metrics consistently demonstrated significantly higher white matter fiber integrity in patients with a better response to VNS (pFDR < 0.05) in different subsegments of thalamocortical tracts. The SVM model achieved a classification accuracy of 94.12%. The inclusion of clinical covariates did not improve the classification performance. The results suggest that the structural integrity of thalamocortical tracts may be linked to therapeutic effectiveness of VNS. This study reveals the great potential of diffusion MRI in improving our understanding of the biological factors associated with the response to VNS therapy.

Oropharyngeal and Aryepiglottic Narrowing for Twang: A Magnetic Resonance Imaging Study.

OBJECTIVE: This study aimed to compare vocal tract configurations between speech and twang qualities. METHODS: Magnetic resonance imaging data were acquired from five professional vocalists while producing the sustained vowel /i/. Width and area measurements were obtained from the axial (ie, transverse) images to evaluate oropharyngeal narrowing and aryepiglottic (AES) narrowing. RESULTS: Four out of five participants exhibited a smaller vocal tract area for twang than for speech at the oropharyngeal level, with the extent of narrowing ranging from 18.8% to 49.6%. Only one participant showed a meaningful decrease in oropharyngeal anteroposterior (AP) width, while three participants showed meaningful decreases in oropharyngeal mediolateral (ML) width for twang compared to speech. At the AES level, all participants showed a smaller vocal tract area for twang than for speech, with the extent of narrowing ranging from 11.8% to 52.4%. Two participants exhibited meaningful decreases in AES AP width, while three participants showed meaningful decreases in AES ML width for twang compared to speech. CONCLUSIONS: Axial imaging revealed oropharyngeal and AES narrowing associated with twang, more prominent in the ML than the AP dimension. Notable individual variations in the mechanism and degree of narrowing at the oropharyngeal and AES levels were observed. The degree of narrowing varied among participants, highlighting the complexity of physiological maneuvers involved in twang production. Future research is necessary to identify broader patterns in twang production for effective pedagogic and therapeutic applications.

Left ventricular reverse remodeling and reduction of interstitial fibrosis in patients with severe aortic stenosis who underwent transcatheter aortic valve implantation.

BACKGROUND: Left ventricular (LV) structural and functional changes have been reported in patients with aortic stenosis (AS) who have undergone transcatheter aortic valve implantation (TAVI); however, the relationship between change in LV structure and systolic function and tissue characteristics assessed via cardiovascular magnetic resonance imaging (CMRI) post-TAVI has been not fully elucidated. This study aimed to investigate this relationship in patients with severe AS who underwent TAVI and CMRI. METHODS: In this retrospective study, 65 patients who underwent TAVI and CMRI at the 6-month follow-up were analyzed. The relationship between percent changes in LV end-diastolic volume (LVEDV), LV end-systolic volume (LVESV), LV ejection fraction (LVEF), and LV mass (LVM) (⊿LVEDV, ⊿LVESV, ⊿LVEF, and ⊿LVM) and those in the native T1 value (⊿native T1) was analyzed using a correlation analysis. Moreover, extracellular volume fraction (ECV) value changes were analyzed. RESULTS: The ⊿native T1 significantly decreased from 1292.8 (1269.9-1318.4) ms at pre-TAVI to 1282.3 (1262.6-1310.2) ms at the 6-month follow-up (P = 0.022). A significant positive correlation between ⊿LVEDV, ⊿LVESV, and ⊿LVM and ⊿native T1 (r = 0.351, P = 0.004; r = 0.339, P = 0.006; r = 0.261, P = 0.035, respectively) and a tendency toward a negative correlation between ⊿LVEF and ⊿native T1 (r = -0.237, P = 0.058) were observed. The ECV value increased significantly from 26.7 % (25.3-28.3) to 28.2 % (25.7-30.5) (P = 0.002). CONCLUSIONS: The decrease in native T1 might be associated with LV reverse remodeling. Evaluating structural and functional changes using CMRI may be useful for patient management.

Is MRI ready to replace biopsy during active surveillance?

Active surveillance (AS) is a conservative management option recommended for patients diagnosed with low-risk prostate cancer (PCa) and selected cases with intermediate-risk PCa. The adoption of prostate MRI in the primary diagnostic setting has sparked interest in its application during AS. This review aims to examine the role and performance of multiparametric MRI (mpMRI) across the entire AS pathway, from initial stratification to follow-up, also relative to the utilization of the Prostate Cancer Radiological Estimation of Change in Sequential Evaluation (PRECISE) criteria. Given the high negative predictive value of mpMRI in detecting clinically significant PCa (csPCa), robust evidence supports its use in patient selection and risk stratification at the time of diagnosis or confirmatory biopsy. However, conflicting results have been observed when using MRI in evaluating disease progression during follow-up. Key areas requiring clarification include addressing the clinical significance of MRI-negative csPCa, optimizing MRI quality, determining the role of biparametric MRI (bpMRI) or mpMRI protocols, and integrating artificial intelligence (AI) for improved performance. CLINICAL RELEVANCE STATEMENT: MRI plays an essential role in the selection, stratification, and follow up of patients in active surveillance (AS) for prostate cancer. However, owing to existing limitations, it cannot fully replace biopsies in the context of AS. KEY POINTS: Multiparametric MRI (mpMRI) has become a crucial tool in active surveillance (AS) for prostate cancer (PCa). Conflicting results have been observed regarding multiparametric MRI efficacy in assessing disease progression. Standardizing MRI-guided protocols will be critical in addressing current limitations in active surveillance for prostate cancer.

Choroid plexus volumes and auditory verbal learning scores are associated with conversion from mild cognitive impairment to Alzheimer's disease.

PURPOSE: Mild cognitive impairment (MCI) can be the prodromal phase of Alzheimer's disease (AD) where appropriate intervention might prevent or delay conversion to AD. Given this, there has been increasing interest in using magnetic resonance imaging (MRI) and neuropsychological testing to predict conversion from MCI to AD. Recent evidence suggests that the choroid plexus (ChP), neural substrates implicated in brain clearance, undergo volumetric changes in MCI and AD. Whether the ChP is involved in memory changes observed in MCI and can be used to predict conversion from MCI to AD has not been explored. METHOD: The current study used data from the Alzheimer's Disease Neuroimaging Initiative (ADNI) database to investigate whether later progression from MCI to AD (progressive MCI [pMCI], n = 115) or stable MCI (sMCI, n = 338) was associated with memory scores using the Rey Auditory Verbal Learning Test (RAVLT) and ChP volumes as calculated from MRI. Classification analyses identifying pMCI or sMCI group membership were performed to compare the predictive ability of the RAVLT and ChP volumes. FINDING: The results indicated a significant difference between pMCI and sMCI groups for right ChP volume, with the pMCI group showing significantly larger right ChP volume (p = .01, 95% confidence interval [-.116, -.015]). A significant linear relationship between the RAVLT scores and right ChP volume was found across all participants, but not for the two groups separately. Classification analyses showed that a combination of left ChP volume and auditory verbal learning scores resulted in the most accurate classification performance, with group membership accurately predicted for 72% of the testing data. CONCLUSION: These results suggest that volumetric ChP changes appear to occur before the onset of AD and might provide value in predicting conversion from MCI to AD.

Gait Analysis and Magnetic Resonance Imaging Characteristics in Patients with Isolated Rapid Eye Movement Sleep Behavior Disorder.

BACKGROUND: Isolated rapid eye movement sleep behavioral disorder (iRBD) can precede neurodegenerative diseases. There is an urgent need for biomarkers to aid early intervention and neuroprotection. OBJECTIVE: The aim is to assess quantitative motor, cognitive, and brain magnetic resonance imaging (MRI) characteristics in iRBD patients. METHODS: Thirty-eight polysomnography-confirmed iRBD patients and 28 age- and sex-matched healthy controls underwent clinical, cognitive, and motor functional evaluations, along with brain MRI. Motor tasks included nine-hole peg test, five-times-sit-to-stand test, timed-up-and-go test, and 4-meter walking test with and without cognitive dual task. Quantitative spatiotemporal gait parameters were obtained using an optoelectronic system. Brain MRI analysis included functional connectivity (FC) of the main resting-state networks, gray matter (GM) volume using voxel-based morphometry, cortical thickness, and deep GM and brainstem volumes using FMRIB's Integrated Registration and Segmentation Tool and FreeSurfer. RESULTS: iRBD patients relative to healthy subjects exhibited a poorer performance during the nine-hole peg test and five-times-sit-to-stand test, and greater asymmetry of arm-swing amplitude and stride length variability during dual-task gait. Dual task significantly worsened the walking performance of iRBD patients more than healthy controls. iRBD patients exhibited nonmotor symptoms, and memory, abstract reasoning, and visuospatial deficits. iRBD patients exhibited decreased FC of pallidum and putamen within the basal ganglia network and occipital and temporal areas within the visuo-associative network, and a reduced volume of the supramarginal gyrus. Brain functional alterations correlated with gait changes. CONCLUSIONS: Subtle motor and nonmotor alterations were identified in iRBD patients, alongside brain structural and functional MRI changes. These findings may represent early signs of neurodegeneration and contribute to the development of predictive models for progression to parkinsonism. © 2024 The Author(s). Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Diagnostic accuracy of carotid plaque instability by noninvasive imaging: a systematic review and meta-analysis.

AIMS: There is increasing evidence that plaque instability in the extracranial carotid artery may lead to an increased stroke risk independently of the degree of stenosis. We aimed to determine diagnostic accuracy of vulnerable and stable plaque using noninvasive imaging modalities when compared to histology in patients with symptomatic and asymptomatic carotid atherosclerosis. METHODS AND RESULTS: Medline Ovid, Embase, Cochrane Library, and Web of Science were searched for diagnostic accuracy of noninvasive imaging modalities (CT, MRI, US) in the detection of 1) vulnerable/stable plaque, and 2) vulnerable/stable plaque characteristics, compared to histology. The quality of included studies was assessed by QUADAS-2 and univariate and bivariate random-effect meta-analyses were performed. We included 36 vulnerable and 5 stable plaque studies in the meta-analysis, and out of 211 plaque characteristics from remaining studies, we classified 169 as vulnerable and 42 as stable characteristics (28 CT, 120 MRI, 104 US characteristics). We found that MRI had high accuracy [90% (95% CI: 82-95%)] in the detection of vulnerable plaque, similar to CT [86% (95% CI: 76-92%); P > 0.05], whereas US showed less accuracy [80% (95% CI: 75-84%); P = 0.013]. CT showed high diagnostic accuracy in visualizing characteristics of vulnerable or stable plaques (89% and 90%) similar to MRI (86% and 89%; P > 0.05); however, US had lower accuracy (77%, P < 0.001 and 82%, P > 0.05). CONCLUSION: CT and MRI have a similar, high performance in detecting vulnerable carotid plaques, whereas US showed significantly less diagnostic accuracy. Moreover, MRI visualized all vulnerable plaque characteristics allowing for a better stroke risk assessment. REGISTRATION: PROSPERO ID CRD42022329690.

Understanding of Consciousness in Absence Seizures: A Literature Review.

Absence seizures are classically associated with behavioral arrest and transient deficits in consciousness, yet substantial variability exists in the severity of the impairment. Despite several decades of research on the topic, the pathophysiology of absence seizures and the mechanisms underlying behavioral impairment remain unclear. Several rationales have been proposed including widespread cortical deactivation, reduced perception of external stimuli, and transient suspension of the default mode network, among others. This review aims to summarize the current knowledge on the neural correlates of impaired consciousness in absence seizures. We review evidence from studies using animal models of absence epilepsy, electroencephalography, functional magnetic resonance imaging, magnetoencephalography, positron emission tomography, and single photon emission computed tomography.

Correlation of functional magnetic resonance imaging features of primary central nervous system lymphoma with vasculogenic mimicry and reticular fibers.

Objective: To deepen the imaging-pathological mechanism of primary central nervous system lymphoma (PCNSL) and provide a theoretical basis for clinical diagnosis and treatment, the functional magnetic resonance imaging (fMRI) characteristics of PCNSL were analyzed, and the relationship between the fMRI characteristics and vasculogenic mimicry (VM) and reticular fiber in PCNSL was discussed. Methods: Ninety-six patients with PCNSL treated in our hospital were divided into three groups according to the pathological examination results, including strong positive group of VM (n = 40), weak positive group of VM (n = 56), strong positive group of reticular fiber (n = 45) and weak positive group of reticular fiber (n = 51). The levels of augmentation index and apparent diffusion coefficient (ADC) were compared among the groups. receiver operator characteristic (ROC) curve analysis was used to analyze the clinical value of ADC value in differential diagnosis of PCNSL. Results: The levels of augmentation index in the strong positive group of VM were significantly higher than that in the weak positive group of VM, and the ADC value in the strong positive group of VM was significantly lower than that in the weak positive group of VM (P < 0.001). The levels of augmentation index in the strong positive group of reticular fiber were significantly higher than that in the weak positive group of reticular fiber, and ADC value in the strong positive group of reticular fiber was significantly lower than that in reticular fiber weak positive group (P < 0.001). Pearson correlation analysis showed that the levels of augmentation index were positively correlated with VM and reticular fiber (r = 0.529, 0.548, P < 0.001) and the ADC value was negatively correlated with VM and reticular fiber (r = -0.485, -0.513, P < 0.001). There was a significant negative correlation between necrotic lesions and VM (r = -0.185, P < 0.05). The area under the curve (AUC) values of average ADC value, minimum ADC value, and maximum ADC value for individual differential diagnosis of PCNSL were 0.920, 0.901, and 0.702, while the AUC of the combined differential diagnosis was 0.985, with a sensitivity of 95.00 % and a specificity of 92.70 %. Conclusion: The levels of augmentation index and the ADC value of PCNSL focus are significantly correlated with VM and reticular fiber, and there is a strong negative correlation between necrotic lesions and VM. MRI imaging technology is of great significance in revealing the biological behavior of PCNSL, which can effectively reveal the relationship between VM and reticular fibers and the MRI characteristics in PCNSL, thereby providing a new imaging basis for the clinical diagnosis and treatment of PCNSL.

18F-FDG PET/CT in early phase of sporadic Creutzfeldt-Jacob disease: A case report.

Key Clinical Message: Creutzfeldt-Jakob disease is a neurodegenerative disorder caused by brain accumulation of a misfolded form of the cellular prion protein, whose diagnosis is challenging, particularly in early stages, due to the variability and nonspecificity of the clinical and radiological features. 18F-fluorodeoxyglucose positron-emitted tomography has the potential to be considered a crucial investigation in these patients, revealing metabolic abnormalities earlier than the conventional neuroimaging analysis. Abstract: A 59-year-old man, the military officer, was referred to our Units for the onset of neurological symptoms rapidly evolving within a month, characterized by akinetic mutism, constructional apraxia, and disorders of spatial orientation. Brain 18F-fluorodeoxyglucose (18F-FDG) positron-emitted tomography (PET)/CT depicted an asymmetric hypometabolism in the left fronto-temporo-parietal cortex, as well as in the left thalamus and the right cerebellar hemisphere, while the glucose metabolism appears to be preserved in the somatosensory cortex and the basal ganglia. Laboratory routine analyses, cerebrospinal fluid routine, infective tests, electroencephalography (EEG), and brain magnetic resonance (MR) were all unremarkable. A positive RT-QuIC result on cerebro-spinal fluid (CSF) was subsequently shown, without any pathogenic gene mutations and, therefore, the result was consistent with a diagnosis of sporadic Creutzfeld-Jacob disease. The clinical evolution was quickly unfavorable, and the patient died about 4 months after hospital admission. FDG PET/computed tomography (CT) has the potential to be considered a crucial investigation in these patients, documenting metabolic changes long time before other diagnostic investigations such as CSF, EEG, brain CT, and brain MR, thus suggesting a greater sensitivity of glucose metabolic evaluation in the early stage of the disease in question.

Potential applications of 7 Tesla magnetic resonance imaging in paediatric neuroimaging: Feasibility and challenges.

The integration of 7 Tesla magnetic resonance imaging (7 T MRI) in adult patients has marked a revolutionary stride in radiology. In this article we explore the feasibility of 7 T MRI in paediatric practice, emphasizing its feasibility, applications, challenges, and safety considerations. The heightened resolution and tissue contrast of 7 T MRI offer unprecedented diagnostic accuracy, particularly in neuroimaging. Applications range from neuro-oncology to neonatal brain imaging, showcasing its efficacy in detecting subtle structural abnormalities and providing enhanced insights into neurological conditions. Despite the promise, challenges such as high cost, discomfort, and safety concerns necessitate careful consideration. Research suggests that, with precautions, 7 T MRI is feasible in paediatrics, yet ongoing studies and safety assessments are imperative.

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Objective: The aim of this study is to explore the practical value of prenatal magnetic resonance imaging (MRI) in the assessment of congenital cystic lung disease in fetuses, to evaluate the relative size of the lesion and the status of lung development, and to make an attempt at utilizing the strength of MRI in post-processing to obtain assessment indicators of the size of the lesion and the status of lung development, with which predictions can be made for the prognosis that these fetuses may face after birth. We retrospectively collected and analyzed the data of fetuses diagnosed with congenital cystic lung disease. Prenatal ultrasound examination of these fetuses led to the diagnosis that they were suspected of having congenital cystic lung disease and the diagnosis was confirmed by subsequent prenatal MRI. The fetuses were followed up to track their condition at birth (postnatal respiratory distress, mechanical ventilation, etc.), whether the fetuses underwent surgical treatment, and the recovery of the fetuses after surgical treatment. The recovery of the fetuses was followed up to explore the feasibility of prenatal MRI examination to assess fetal congenital pulmonary cystic disease, and to preliminarily explore the predictive value of prenatal MRI for the prognosis of fetuses with congenital pulmonary cystic disease. Methods: MRI fetal images were collected from pregnant women who attended the West China Second University Hospital of Sichuan University between May 2018 and March 2023 and who were diagnosed with fetal congenital pulmonary cystic disease by prenatal ultrasound and subsequent MRI. Fetal MRI images of congenital cystic lung disease were post-processed to obtain the fetal lung lesion volume, the fetal affected lung volume, the healthy lung volume, and the fetal head circumference measurements. The signal intensity of both lungs and livers, the lesion volume/the affected lung volume, the lesion volume/total lung volume, the cystic volume ratio (CVR), and the bilateral lung-liver signal intensity ratio were measured. The feasibility and value of MRI post-processing acquisition indexes for evaluating the prognosis of fetuses with congenital cystic lung disease were further analyzed by combining the follow-up results obtained 6 months after the birth of the fetus. Logistic regression models were used to quantify the differences in maternal age, gestational week at the time of MRI, CVR, and bilateral lung-to-liver signal intensity ratio, and to assess whether these metrics correlate with poor prognosis. Receiver operating characteristic (ROC) curves were used to assess the value of the parameters obtained by MRI calculations alone and in combination with multiple metrics for predicting poor prognosis after birth. Results: We collected a total of 67 cases of fetuses diagnosed with congenital cystic lung disease by fetal MRI between May 2018 and March 2023, and excluded 6 cases with no normal lung tissue in the affected lungs, 11 cases of fetal induction, and 3 cases of loss of pregnancy. In the end, 47 cases of fetuses with congenital cystic lung disease were included, of which 30 cases had a good prognosis and 17 cases had a poor prognosis. The difference in the difference between the signal intensity ratios of the affected and healthy sides of the lungs and livers of the fetuses in the good prognosis group and that in the poor prognosis group was statistically significant (P<0.05), and the signal intensity ratio of the healthy side of the lungs and livers was higher than the signal intensity ratio of the affected side of the lungs and livers. Further analysis showed that CVR (odds ratio [OR]=1.058, 95% confidence interval [CI]: 1.014-1.104), and the difference between the lung-to-liver signal intensity ratios of the affected and healthy sides (OR=0.814, 95% CI: 0.700-0.947) were correlated with poor prognosis of birth in fetuses with congenital cystic lung disease. In addition, ROC curve analysis showed that the combined application of lesion volume/affected lung volume and the observed difference in the signal intensity ratio between the affected and healthy lungs and liver predicted the prognosis of children with congenital cystic lung disease more accurately than the single-parameter judgment did, with the area under the curve being 0.988, and the cut-off value being 0.33, which corresponded to a sensitivity of 100%, a specificity of 93.3%, and a 95% CI of 0.966-1.000. Conclusions: Based on the MRI of fetuses with congenital cystic lung disease, we obtained information on lesion volume, lesion volume/affected lung volume, lesion volume/total lung volume, CVR, and bilateral lung-to-liver signal intensity ratio difference, all of which showing some clinical value in predicting the poor prognosis in fetuses with congenital cystic lung disease. Furthermore, among the combined indexes, the lesion volume/affected lung volume and bilateral lung-to-liver signal intensity ratio difference are more effective predictors for the poor prognosis of fetuses with congenital cystic lung disease, and show better efficacy in predicting the poor prognosis of fetuses with congenital cystic lung disease. This provides a new and effective predictive method for further assessment of pulmonary lung development in fetuses with congenital cystic lung disease, and helps improve the assessment and prediction of the prognosis of fetuses with congenital cystic lung disease.

Impact of pre-operative abdominal MRI on survival for patients with resected pancreatic carcinoma: a population-based study.

Background: This study determined the impact of pre-operative abdominal MRI on all-cause mortality for patients with resected PDAC. Methods: All adult (≥18 years) PDAC patients who underwent pancreatectomy between January 2011 and December 2022 in Ontario, Canada, were identified for this population-based cohort study (ICD-O-3 codes: C250, C251, C252, C253, C257, C258). Patient demographics, comorbidities, PDAC stage, medical and surgical management, and survival data were sourced from multiple linked provincial administrative databases at ICES. All-cause mortality was compared between patients with and without a pre-operative abdominal MRI after controlling for multiple covariates. Findings: A cohort of 4579 patients consisted of 2432 men (53.1%) and 2147 women (46.9%) with a mean age of 65.2 years (standard deviation: 11.2 years); 2998 (65.5%) died while 1581 (34.5%) survived. Median follow-up duration post-resection was 22.4 months (interquartile range: 10.8-48.8 months), and median survival post-pancreatectomy was 25.9 months (95% confidence interval [95% CI]: 24.8, 27.5). Patients who underwent a pre-operative abdominal MRI had a median survival of 33.1 months (95% CI: 30.7, 37.2) compared to 21.1 months (95% CI: 19.8, 22.6) for all others. A total of 2354/4579 (51.4%) patients underwent a pre-operative abdominal MRI, which was associated with a 17.2% (95% CI: 11.0, 23.1) decrease in the rate of all-cause mortality, with an adjusted hazard ratio (aHR) of 0.828 (95% CI: 0.769, 0.890). Interpretation: Pre-operative abdominal MRI was associated with improved overall survival for PDAC patients who underwent pancreatectomy, possibly due to better detection of liver metastases than CT. Funding: Northern Ontario Academic Medicine Association (NOAMA) Clinical Innovation Fund.

The Diagnostic Utility of Contrast-Enhanced FLAIR Imaging in the Diagnosis of Pediatric Uveitis.

Objectives: Contrast-enhanced FLAIR fat-suppressed (CE-FLAIR-FS) imaging can potentially increase the diagnostic accuracy of uveal diseases and ultimately provide better patient management. This study aimed to determine the diagnostic value of CE-FLAIR-FS imaging versus contrast-enhanced T1-weighted imaging (CE-T1WI) in the assessment of pediatric patients with uveitis. Material and methods: Twenty-one children with uveitis who underwent whole brain magnetic resonance imaging (MRI), including CE-FLAIR-FS and CE-T1WI, were retrospectively included in the study. We evaluated the presence of uveal tract contrast enhancement with thickening, vitreous humor signal abnormality, and accompanying brain abnormalities. The uveal enhancement intensity was assessed semiquantitatively as mild, moderate, and marked uveitis compared to CE-T1WI and CE-FLAIR-FS images. Results: Panuveitis (61.9%) was the most frequent anatomic location, and most of them were idiopathic (47.6%). Of the 42 eyes with clinical uveitis, enhancement of the uveal tract was observed on CE-FLAIR-FS images in 21 eyes (50%), while in 5 eyes (11.9%) on CE-T1WI. The sensitivity of CE-FLAIR-FS in panuveitis was detected to be quite high (80.8%). The number of affected eyes and enhancement degree were found to be higher on CE-FLAIR-FS (p < 0.001). In assessing the severity of uveitis, CE-FLAIR-FS grades were significantly higher and more sensitive than CE-T1WI (p < 0.001, Z: -4.347). Three patients had vitreous abnormal signals on CE-FLAIR-FS images, but none on CE-T1WI. Conclusion: CE-FLAIR-FS plays a significant role in the diagnosis of pediatric uveitis, identifying the involvement and severity of the uveal inflammation and guiding the appropriate management. It would be beneficial to add it as a standard sequence to the routine MRI protocol for uveal pathologies.

Multiple sclerosis relapse presenting as trigeminal neuralgia.

I present here a case of trigeminal neuralgia (TGN), which is a highly disabling disorder characterized by brief and recurrent shock-like episodes of facial pain. TGN occurs in 2% of people with MS. A 54-year-old woman diagnosed with multiple sclerosis (MS) in 2008 and who was in remission stopped taking her disease-modifying therapy (DMT) in 2018 due to a lack of relapses presented to our facility with excruciating right facial pain. Magnetic resonance imaging (MRI) of the brain with gadolinium showed enhancing plaque involving the proximal cisternal portion of the right trigeminal nerve on axial and sagittal sections. She was started on carbamazepine 300 mg 4 times a day. This case highlights the need for early diagnosis by MRI with gadolinium enhancement and prompt initiation of treatment helped her pain to subside and was able to return a week later to the MS clinic to be restarted on her prior DMT to prevent further MS relapses.

An overview of early-onset cerebellar ataxia: a practical guideline.

Early onset ataxias (EOAs) are a heterogeneous group of rare neurological disorders that not only involve the central and peripheral nervous system but also involve other organs. They are mainly manifested by degeneration or abnormal development of the cerebellum occurring before the age of 25 years and typically the pattern of inheritance is autosomal recessive.The diagnosis of autosomal recessive cerebellar ataxias (ARCAs) is confirmed by the clinical, laboratory, electrophysiological examination, neuroimaging findings, and mutation analysis when the causative gene is detected. Correct diagnosis is crucial for appropriate genetic counseling, estimating the prognosis, and, in some cases, pharmacological intervention. The wide variety of genotypes with a heterogeneous phenotypic manifestation makes the diagnostic work-up challenging, time-consuming, and expensive, not only for the clinician but also for the children and their parents. In this review, we focused on the step-by-step approach in which cerebellar ataxia is a prominent sign. We also outline the most common disorders in ataxias with early-onset manifestations.

Cerebrovascular reactivity MRI as a biomarker for cerebral small vessel disease-related cognitive decline: Multi-site validation in the MarkVCID Consortium.

INTRODUCTION: Vascular contributions to cognitive impairment and dementia (VCID) represent a major factor in cognitive decline in older adults. The present study examined the relationship between cerebrovascular reactivity (CVR) measured by magnetic resonance imaging (MRI) and cognitive function in a multi-site study, using a predefined hypothesis. METHODS: We conducted the study in a total of three analysis sites and 263 subjects. Each site performed an identical CVR MRI procedure using 5% carbon dioxide inhalation. A global cognitive measure of Montreal Cognitive Assessment (MoCA) and an executive function measure of item response theory (IRT) score were used as outcomes. RESULTS: CVR and MoCA were positively associated, and this relationship was reproduced at all analysis sites. CVR was found to be positively associated with executive function. DISCUSSION: The predefined hypothesis on the association between CVR and a global cognitive score was validated in three independent analysis sites, providing support for CVR as a biomarker in VCID. HIGHLIGHTS: This study measured a novel functional index of small arteries referred to as cerebrovascular reactivity (CVR). CVR was positively associated with global cognition in older adults. This finding was observed in three independent cohorts at three sites. Our statistical analysis plan was predefined before beginning data collection.

Nonionizing diagnostic imaging modalities for visualizing health and pathology of periodontal and peri-implant tissues.

Radiographic examination has been an essential part of the diagnostic workflow in periodontology and implant dentistry. However, radiographic examination unavoidably involves ionizing radiation and its associated risks. Clinicians and researchers have invested considerable efforts in assessing the feasibility and capability of utilizing nonionizing imaging modalities to replace traditional radiographic imaging. Two such modalities have been extensively evaluated in clinical settings, namely, ultrasonography (USG) and magnetic resonance imaging (MRI). Another modality, optical coherence tomography (OCT), has been under investigation more recently. This review aims to provide an overview of the literature and summarize the usage of USG, MRI, and OCT in evaluating health and pathology of periodontal and peri-implant tissues. Clinical studies have shown that USG could accurately measure gingival height and crestal bone level, and classify furcation involvement. Due to physical constraints, USG may be more applicable to the buccal surfaces of the dentition even with an intra-oral probe. Clinical studies have also shown that MRI could visualize the degree of soft-tissue inflammation and osseous edema, the extent of bone loss at furcation involvement sites, and periodontal bone level. However, there was a lack of clinical studies on the evaluation of peri-implant tissues by MRI. Moreover, an MRI machine is very expensive, occupies much space, and requires more time than cone-beam computed tomography (CBCT) or intraoral radiographs to complete a scan. The feasibility of OCT to evaluate periodontal and peri-implant tissues remains to be elucidated, as there are only preclinical studies at the moment. A major shortcoming of OCT is that it may not reach the bottom of the periodontal pocket, particularly for inflammatory conditions, due to the absorption of near-infrared light by hemoglobin. Until future technological breakthroughs finally overcome the limitations of USG, MRI and OCT, the practical imaging modalities for routine diagnostics of periodontal and peri-implant tissues remain to be plain radiographs and CBCTs.

Reversible splenial lesion syndrome in Anti-N-methyl-D-aspartate receptor encephalitis.

Here we described an 18-year-old woman who were initially misdiagnosed as psychiatric disorders in a psychiatric institution. She was transferred to our neurological ward because of impaired consciousness. Neuronal antibody testing confirmed the diagnosis of anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis. Cerebral magnetic resonance imaging (MRI) revealed a concomitant disorder named reversible splenial lesion syndrome (RESLES). After administration of combined immunotherapy, the patient recovered completely 3 months after discharge. To our knowledge, co-occurrence of RESLES and anti-NMDAR encephalitis was only described in two patients with teratoma and we provide another case without teratoma. We highlight that anti-NMDAR antibodies can be added to the multiple causes of RESLES. It is therefore imperative for clinicians to detect anti-neuronal antibodies in patients with RESLES to avoid missed diagnosis.