Search Results (4)

The radiological finding of Dark White Matter (DWM)—characteristic diffuse subcortical white matter hypointensity on T2/FLAIR sequences—is underrecognized, but has important clinical implications. Recent systematic evidence shows that over 60% of previously published cases showed seizures in association with DWM findings—it is also particularly predictive of the underlying etiology, particularly non-ketotic hyperglycemic hyperosmolar state (NKH). Based on our previous work, we reinterpret the data, focusing only on patients with seizures and DWM, to summarize the most essential and distinguishing features of these patients. Both cortical and subcortical abnormalities in DWM are more frequently associated with anti-MOG encephalitis. DWM with or without cortical involvement is more commonly found in NKH among patients with seizures. This updated systematic review will describe the proposed pathophysiological mechanisms, clinical associations, and implications for DWM in patients with seizures, and highlight how early recognition of DWM may allow for targeted diagnostic strategies and treatment options. We expanded our previous search with details regarding seizure features, our results show that DWM is associated with repetitive seizures and Status Epilepticus (both convulsive and non), in line with other peri-ictal MRI abnormalities associated with prolonged seizure activity. DWM-associated seizures are mostly focal, rather than generalized. Moreover, the high percentage of clinical recovery at follow-up suggests that DWM may be predictive of a good outcome, especially in NKH cases, although this needs to be confirmed in future studies. Full article

MRI plays an increasingly important role in the diagnosis of status epilepticus (SE). Approximately half of patients with SE do not have pre-existing epilepsy, and the cause of de novo SE is frequently unknown. The role of MRI in the identification of causes of SE is invaluable. MRI is often helpful as a diagnostic tool in cases of non-convulsive status epilepticus (NCSE) with ambiguous EEG findings. Thus, MRI is recommended for all patients presenting with de novo SE, patients with known epilepsy with the first episode of SE and NCSE with equivocal EEG. Different peri-ictal MRI (PMA) alterations may be seen during ongoing SE or briefly after its cessation. They commonly present as peri-ictal hyper-perfusion, diffusion restriction and/or FLAIR-hyperintensity affecting specific brain areas such as the cortex, hippocampus, pulvinar of the thalamus, splenium of the corpus callosum, claustrum or cerebellum, frequently in combination, suggesting the existence of a “status epilepticus network”. MRI sequences, which are necessary for detecting PMA, include diffusion-weighted imaging, fluid attenuated inversion recovery, T1-weighted imaging with and without contrast application, as well as perfusion sequences such as arterial spin labeling. Recent research suggests that they may serve as biomarkers for predicting an outcome in SE. Patients with PMA seem to have a higher mortality rate compared to those without PMA. However, there is still a substantial knowledge gap and there are many open questions related to imaging in SE. Further prospective quantitative MRI studies with uniform protocols, timing and follow-up periods are needed to answer these important and clinically relevant questions. Full article

Background/Objectives: Brain magnetic resonance imaging (MRI) often reveals acute peri-ictal abnormalities (PMAs) during or shortly after status epilepticus (SE) but also following single seizures (SiS) or clusters of seizures (CS). However, the incidence, characteristics, and progression remain not clearly known. This study aimed to investigate incidence, clinical correlations, and evolution of PMAs in SE, CS, and SiS patients. Methods: This prospective observational study enrolled patients with SE, CS, and SiS who underwent MRI within 120 h of the ictal event. Demographic, clinical, EEG, and MRI data were collected. Patients with PMAs (PMAs+) underwent serial follow-up MRI. Incidence, association with clinical characteristics, and progression of PMAs were analyzed across the three groups. Results: Among 76 patients (30 SE, 22 CS, 24 SiS), PMAs were observed in 31 (41%), with a significant difference between groups (p = 0.011), as PMAs were less frequent in SiS (17%) compared to SE (57%) and CS (45%) patients. Acute symptomatic SE/seizures were significantly more common in PMAs+ compared to PMAs− in the overall cohort (52% vs. 29%; p = 0.045) and in the SiS group (100% vs. 25%; p = 0.031). History of epilepsy was less frequent in PMAs+ in the whole cohort (13% vs. 40%; p = 0.011) and in SE in particular (12% vs. 46%, p = 0.049). No association between PMAs and seizure type, SE duration, etiology, time to MRI, and EEG findings (p > 0.005) was found. The temporal cortex and hippocampus were most frequently affected by PMAs. Follow-up MRI performed in 16 patients showed resolution of PMAs in 75% (5/7 SE, 3/6 CS, 3/3 SiS) within a median time of 24 days (IQR: 8–39). Conclusions: PMAs were more common in SE and CS than in SiS. Acute underlying pathology was frequently associated with PMAs. While duration of ictal activity is an important factor, it was not the sole determinant. Most PMAs resolved, particularly in SiS. Further studies are needed to clarify the pathophysiological mechanism and clinical implications of PMAs. Full article

Epilepsy is a common clinical manifestation and a source of significant morbidity in patients with brain tumors. Neuroimaging has a pivotal role in neuro-oncology practice, including tumor detection, differentiation, grading, treatment guidance, and posttreatment monitoring. In this review, we highlight studies demonstrating that imaging can also provide information about brain tumor-associated epileptogenicity and assist delineation of the peritumoral epileptic cortex to optimize postsurgical seizure outcome. Most studies focused on gliomas and glioneuronal tumors where positron emission tomography (PET) and advanced magnetic resonance imaging (MRI) techniques can detect metabolic and biochemical changes associated with altered amino acid transport and metabolism, neuroinflammation, and neurotransmitter abnormalities in and around epileptogenic tumors. PET imaging of amino acid uptake and metabolism as well as activated microglia can detect interictal or peri-ictal cortical increased uptake (as compared to non-epileptic cortex) associated with tumor-associated epilepsy. Metabolic tumor volumes may predict seizure outcome based on objective treatment response during glioma chemotherapy. Advanced MRI, especially glutamate imaging, can detect neurotransmitter changes around epileptogenic brain tumors. Recently, developed PET radiotracers targeting specific glutamate receptor types may also identify therapeutic targets for pharmacologic seizure control. Further studies with advanced multimodal imaging approaches may facilitate development of precision treatment strategies to control brain tumor-associated epilepsy. Full article