Extensive brainstem lesions in myelin oligodendrocyte glycoprotein antibody-associated disease (MOGAD): A case report.

Myelin oligodendrocyte glycoprotein antibody-associated disease is a group of central nervous system demyelinating disorders caused by autoantibodies. While myelin oligodendrocyte glycoprotein antibody-associated disease typically presents as optic neuritis and myelitis in adults, this case report details a patient with brainstem lesions. A 45-year-old male presented with episodes of vertigo, nystagmus, and diplopia in left lateral gaze, which had persisted for 2 months, accompanied by headache. Computed tomography showed hyperdensity extending from the left side of the pons to the middle cerebellar peduncle. Magnetic resonance imaging revealed lesions exhibiting heterogeneous diffusion restriction, with enhancement that included granular and linear patterns. 18F-fluorodeoxyglucose positron emission tomography demonstrated increased uptake in these lesions. Following further evaluation, myelin oligodendrocyte glycoprotein antibody-associated disease was diagnosed. Treatment with high-dose corticosteroids initially alleviated symptoms, but symptoms flared upon reduction of the steroids. This case underscores the importance of considering myelin oligodendrocyte glycoprotein antibody-associated disease in the differential diagnosis of brainstem lesions and discusses distinguishing imaging features from similar conditions.

Neuromyelitis optica spectrum disorder mimicking cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy with symmetrical lesions in the temporal poles and external capsules on MRI.

Symmetrical lesions in the temporal poles and external capsules on brain MRI are known as radiological markers of cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL); however, similar imaging findings have also been reported in neuromyelitis optica spectrum disorder (NMOSD), and this study investigated the frequency of such findings. The study included 55 NMOSD patients who met the 2015 international NMO diagnosis panel (IPND) criteria and were positive for aquaporin-4 antibodies (AQP4-Ab). Images were evaluated based on the consensus of two neuroradiologists, and brain lesions were detected in 33 patients, of whom 2 (6%) had symmetrical lesions in both the temporal poles and external capsules, and 1 (3%) had symmetrical lesions confined to the external capsules. Therefore, when symmetrical lesions in the temporal poles and external capsules are observed on MRI, NMOSD should be considered in the differential diagnosis.

Predicting the O'Kelly-Marotta scale score after flow-diverter stent placement using silent MRA.

PURPOSE: Flow-diverter (FD) stents were developed to treat aneurysms that are difficult to treat with conventional coiling or surgery. This study aimed to compare usefulness of Silent MRA and TOF (time of flight) -MRA in patients with aneurysms after FD placement. MATERIALS AND METHODS: We retrospectively collected images from 22 patients with 23 internal carotid artery aneurysms treated with FD. Two radiologists conducted MRA and DSA experiments. In the first reading experiment, the radiologists evaluated the aneurysm filling by employing Silent MRA and TOF-MRA and utilizing the modified O'Kelly-Marotta (OKM) scale, a four-class classification system for aneurysms after FD placement. We then calculated the agreement between the modified OKM scale on MRA and the original OKM scale on DSA. In the second reading experiment, the radiologists rated blood flow within the FD using a five-point scale. RESULTS: The weighted kappa value of the OKM scale between DSA and TOF-MRA was 0.436 (moderate agreement), and that between DSA and Silent MRA was 0.943 (almost perfect agreement). The accuracies for the four-class classification were 0.435 and 0.870 for TOF-MRA and Silent MRA, respectively. The mean score of blood flow within FD for TOF-MRA was 2.43 ± 0.90 and that for Silent MRA was 3.04 ± 1.02 (P < 0.001). CONCLUSION: Silent MRA showed a higher degree of agreement than TOF-MRA in aneurysm filling with DSA. In addition, Silent MRA was significantly superior to TOF-MRA in depicting blood flow within the FD. Therefore, Silent MRA is clinically useful for the follow-up of patients after FD placement.

Differentiating multiple sclerosis and neuromyelitis optica spectrum disorders through pontine trigeminal nerve lesions: A comparative MRI study.

PURPOSE: Multiple sclerosis (MS) and neuromyelitis optica spectrum disorder (NMOSD) are two major demyelinating diseases affecting the central nervous system (CNS). The objective of this study is to evaluate the prevalence of pontine trigeminal nerve lesions in patients diagnosed with MS and NMOSD using MRI. METHODS: This retrospective study included patients diagnosed with MS or NMOSD between July 2018 and July 2023. MS patients were clinically diagnosed using the 2017 McDonald criteria, while NMOSD patients were those who met the 2015 International Panel for NMO Diagnosis (IPND) criteria and were positive for Aquaporin-4 Antibody (AQP4-Ab). RESULTS: The study included a total of 90 patients, with 45 diagnosed with MS and another 45 with NMOSD. Pontine trigeminal nerve lesions were observed in both MS and NMOSD, but were more prevalent in MS patients (20 % vs. 2 %, p = 0.008). Root entry zone (REZ) lesions were found in 4 of 45 MS patients, accounting for 9 % (95 % CI: 3 %-17 %), and were absent in the NMOSD group; however, there was no significant difference between the two groups (p = 0.12). Of the MS patients with pontine trigeminal nerve lesions, 6 out of 9 (63 %; 95 % CI, 36 %-98 %) exhibited bilateral lesions, which was significantly more prevalent compared to the NMOSD group (13 % vs. 0 %, p = 0.03). CONCLUSIONS: The presence of pontine trigeminal nerve lesions, particularly when bilateral, are significantly more prevalent in MS patients than in those with NMOSD, suggesting their utility as a distinctive marker and potential diagnostic indicator specifically for MS.

Solitary Fibrous Tumor With an Acute Subdural Hematoma: A Case Report and Review of the Literature.

Solitary fibrous tumor (SFT) is a rare interstitial tumor that originates from various soft tissues, and SFTs occurring within the cranium are extremely rare. While intracranial SFTs with cerebral hemorrhage or subarachnoid hemorrhage have been reported, there have been no reports of intracranial SFTs causing subdural hematoma. In this case, we report on an intracranial SFT accompanied by a subdural hematoma. A 29-year-old female was emergently transported due to the sudden onset of persistent headache and vomiting that began the night before. CT and MRI imaging revealed a hemorrhagic tumor under the tentorium and an acute subdural hematoma extending along the tentorium. The excised tumor was diagnosed as an SFT through histopathological examination. After undergoing radiation therapy, no recurrence has been observed. This is the first case report of an SFT accompanied by a subdural hematoma, and it is vital to recognize that SFTs can be associated with subdural hematomas for proper diagnosis and treatment planning.

Deep learning model for predicting gestational age after the first trimester using fetal MRI.

OBJECTIVES: To evaluate a deep learning model for predicting gestational age from fetal brain MRI acquired after the first trimester in comparison to biparietal diameter (BPD). MATERIALS AND METHODS: Our Institutional Review Board approved this retrospective study, and a total of 184 T2-weighted MRI acquisitions from 184 fetuses (mean gestational age: 29.4 weeks) who underwent MRI between January 2014 and June 2019 were included. The reference standard gestational age was based on the last menstruation and ultrasonography measurements in the first trimester. The deep learning model was trained with T2-weighted images from 126 training cases and 29 validation cases. The remaining 29 cases were used as test data, with fetal age estimated by both the model and BPD measurement. The relationship between the estimated gestational age and the reference standard was evaluated with Lin's concordance correlation coefficient (ρc) and a Bland-Altman plot. The ρc was assessed with McBride's definition. RESULTS: The ρc of the model prediction was substantial (ρc = 0.964), but the ρc of the BPD prediction was moderate (ρc = 0.920). Both the model and BPD predictions had greater differences from the reference standard at increasing gestational age. However, the upper limit of the model's prediction (2.45 weeks) was significantly shorter than that of BPD (5.62 weeks). CONCLUSIONS: Deep learning can accurately predict gestational age from fetal brain MR acquired after the first trimester. KEY POINTS: • The prediction of gestational age using ultrasound is accurate in the first trimester but becomes inaccurate as gestational age increases. • Deep learning can accurately predict gestational age from fetal brain MRI acquired in the second and third trimester. • Prediction of gestational age by deep learning may have benefits for prenatal care in pregnancies that are underserved during the first trimester.

Diagnostic accuracy of deep-learning with anomaly detection for a small amount of imbalanced data: discriminating malignant parotid tumors in MRI.

We hypothesized that, in discrimination between benign and malignant parotid gland tumors, high diagnostic accuracy could be obtained with a small amount of imbalanced data when anomaly detection (AD) was combined with deep leaning (DL) model and the L2-constrained softmax loss. The purpose of this study was to evaluate whether the proposed method was more accurate than other commonly used DL or AD methods. Magnetic resonance (MR) images of 245 parotid tumors (22.5% malignant) were retrospectively collected. We evaluated the diagnostic accuracy of the proposed method (VGG16-based DL and AD) and that of classification models using conventional DL and AD methods. A radiologist also evaluated the MR images. ROC and precision-recall (PR) analyses were performed, and the area under the curve (AUC) was calculated. In terms of diagnostic performance, the VGG16-based model with the L2-constrained softmax loss and AD (local outlier factor) outperformed conventional DL and AD methods and a radiologist (ROC-AUC = 0.86 and PR-ROC = 0.77). The proposed method could discriminate between benign and malignant parotid tumors in MR images even when only a small amount of data with imbalanced distribution is available.

Intracranial myxoid mesenchymal tumor with EWSR1-CREB1 gene fusion: a case report and literature review.

Intracranial myxoid mesenchymal tumors harboring EWSR1 fusions with CREB transcriptional factor gene families were recently described in several case reports and a few case series and this tumor closely resembles the myxoid variant of angiomatoid fibrous histiocytoma. We herein present an intracranial mesenchymal myxoid tumor arising in the third ventricle of a middle-aged woman. The tumor displayed prominent myxoid features consisting of mildly atypical oval to round cells, arranged in reticular and cord-like structures, with starburst-like amianthoid fibers, whereas it lacked pseudoangiomatoid spaces, pseudocapsules and lymphoid cuffing. Immunophenotypically, tumor cells were positive for EMA, desmin, and ALK (focal). EWSR1 and CREB1 rearrangements were identified using FISH assay. The proliferation index was low. It is currently uncertain whether these myxoid tumors represent a variant of angiomatoid fibrous histiocytoma or a novel tumor entity.