Clinicoradiologic Criteria for the Diagnosis of Stroke-like Episodes in MELAS.

Background and Objectives: Stroke-like episodes (SLEs) in patients with mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS) syndrome are often misdiagnosed as acute ischemic stroke (AIS). We aimed to determine unique clinical and neuroimaging features for SLEs and formulate diagnostic criteria. Methods: We retrospectively identified patients with MELAS admitted for SLEs between January 2012 and December 2021. Clinical features and imaging findings were compared with a cohort of patients who presented with AIS and similar lesion topography. A set of criteria was formulated and then tested by a blinded rater to evaluate diagnostic performance. Results: Eleven MELAS patients with 17 SLE and 21 AISs were included. Patients with SLEs were younger (median 45 [37-60] vs 77 [68-82] years, p < 0.01) and had a lower body mass index (18 ± 2.6 vs 29 ± 4, p < 0.01), more commonly reported hearing loss (91% vs 5%, p < 0.01), and more commonly presented with headache and/or seizures (41% vs 0%, p < 0.01). The earliest neuroimaging test performed at presentation was uniformly a noncontrast CT. Two main patterns of lesion topography with a stereotypical spatiotemporal evolution were identified-an anterior pattern (7/21, 41%) starting at the temporal operculum and spreading to the peripheral frontal cortex and a posterior pattern (10/21, 59%) starting at the cuneus/precuneus and spreading to the lateral occipital and parietal cortex. Other distinguishing features for SLEs vs AIS were cerebellar atrophy (91% vs 19%, p < 0.01), previous cortical lesions with typical SLE distribution (46% vs 9%, p = 0.03), acute lesion tissue hyperemia and venous engorgement on CT angiography (CTA) (45% vs 0%, p < 0.01), and no large vessel occlusion on CTA (0% vs 100%, p < 0.01). Based on these clinicoradiologic features, a set of diagnostic criteria were constructed for possible SLE (sensitivity 100%, specificity 81%, AUC 0.905) and probable SLE (sensitivity 88%, specificity 95%, AUC 0.917). Discussion: Clinicoradiologic criteria based on simple anamnesis and a CT scan at presentation can accurately diagnose SLE and lead to early administration of appropriate therapy. Classification of Evidence: This study provides Class III evidence that an algorithm using clinical and imaging features can differentiate stroke-like episodes due to MELAS from acute ischemic strokes.

Multicentric non-enhancing lesions in glioblastoma: A retrospective study.

Glioblastoma (GBM) typically presents as a single lesion. Multicentric GBM are defined as well separated lesions on MRI (enhancing and non-enhancing). Multicentric GBM with non-enhancing lesions (MNE-GBM) are rarely described in literature. We aimed at describing the radiologic characteristics, treatment, and clinical course of those patients. The institutional neuropathological database was searched for GBM patients diagnosed between 1/1/2015 and 31/05/2018. All pre-operative MRI brain scans were reviewed to identify patients with MNE-GBM. Electronic medical records and follow-up MRI scans were reviewed to assess progression-free survival (PFS) and overall survival (OS). Out of 149 adult patients with newly diagnosed GBM, 12 met the inclusion criteria of MNE-GBM, all of them presented at least one enhancing lesion. Median follow-up for the MNE-GBM patients was 16.1 months. At last follow-up, all patients had recurrence (median PFS 7.6 months) and eleven patients had deceased. Median OS was 16.2 months (95% CI, 4.1-27.5). Eleven patients received radiotherapy concomitant with temozolomide as initial treatment. Radiation field included all the disease foci (enhancing and non-enhancing lesions) in 8 patients, five of them progressed within the non-enhancing lesion. Three patients did not receive radiation for the entire non-enhancing lesions, and two of them progressed within the non-irradiated areas. In conclusion, MNE-GBM is not rare, and has high risk of aggressive progression within the separate non-enhancing lesion.

Saliva immunoglobulin free light chain analysis for monitoring disease activity and response to treatment in multiple sclerosis.

BACKGROUND: Immunoglobulin free light chains (FLC) have recently gained considerable interest as new promising intrathecal biomarkers of multiple sclerosis (MS). However, lumbar puncture is invasive and not practical for monitoring disease course. This study aimed to assess the utility of saliva FLC as a biomarker of disease activity and response to treatment in MS METHODS: Western blotting was used to study saliva FLC monomers and dimers. The intensity of immunoreactive FLC bands was quantified by electrophoresis analysis, and the obtained values were used as FLC indices to account for kappa and lambda FLC monomer and dimer levels. Firth's logistic regression analysis suitable to study small cohorts was applied to compare FLC levels between M.S. patients in relapse, MS patients in remission, and healthy controls. Association between FLC levels and clinical and radiological parameters was analyzed. RESULTS: 55 MS patients and 40 healthy controls were evaluated. Saliva FLC levels were significantly higher in relapse compared to remission. Logistic regression analysis employing a combination of FLC indices confirmed the significant difference between these two groups. The FLC levels were significantly reduced by treatment with corticosteroids. During remission, patients treated with disease-modifying therapies had lower levels of FLC compared to untreated patients. The increased FLC levels were associated with the presence of gadolinium-enhancing lesions, but not with MRI T2 lesion load and EDSS scores. During individual patient follow-up, the changes of the saliva FLC levels were in concordance with the disease activity status. CONCLUSIONS: Saliva FLC levels may be a useful biomarker for discriminating between stable remission and active disease. The developed test may serve as a new, non-invasive, and inexpensive tool for monitoring disease activity and response to treatment in MS.

Cystic Duct Embolization with Chemical Gallbladder Ablation for the Treatment of Acute Calculous Cholecystitis in High-Risk Patients: A Prospective Single-Center Study.

PURPOSE: To demonstrate the feasibility of cystic duct embolization and chemical gallbladder ablation as an alternative to cholecystectomy in high-risk patients with calculous cholecystitis who were not candidates for surgery. MATERIALS AND METHODS: This prospective study included 10 patients with acute cholecystitis (7 males and 3 females) aged 70-91 years (average age, 81.6 years) between 2013 and 2019. A cholecystostomy catheter was inserted during the acute phase, followed by cystic duct coil embolization performed via the existing drainage tube tract. Once asymptomatic, 3% aethoxysklerol was injected into the gallbladder, and the drain was removed upon sonographic confirmation that the gallbladder remained contracted. Each phase of the procedure was performed with an interval of 2-3 weeks. Clinical, cholangiographic, and sonographic data were collected before and after drain removal at 1-month follow-up. RESULTS: Cystic duct embolization was technically successful in all patients, with no immediate post-procedure complications. Gallbladder ablation performed in 10 patients was technically successful in all of them (median follow-up, 11 months). One patient required repeat ablation at 14 months, and the prolonged biliary excretions of 1 other patient ceased only at 8 months. CONCLUSIONS: Cystic duct embolization with gallbladder ablation is a feasible procedure for patients in whom cholecystectomy is contraindicated.

Detection of cavernous malformations after whole-brain radiotherapy in primitive neuroectodermal tumor patients-comparing susceptibility-weighted imaging and T2 gradient-echo sequences.

PURPOSE: The aim of this retrospective study is to investigate the value of the susceptibility-weighted imaging (SWI) sequence compared to gradient echo (GRE) in the detection and follow-up of cavernous malformations in patients who underwent whole-brain irradiation as part of their medulloblastoma treatment. METHODS: We retrospectively examined MRI studies of 28 subjects (16 males, 12 females) who received whole-brain irradiation as part of their treatment. Ages at irradiation ranged from 2 to 38 years. All patients were periodically followed up with MR imaging (ranging from 9 to 336 months). Two neuroradiologists reviewed studies of the same patients, comparing the number of suspected cavernomas detected on GRE and SWI sequences performed at different times (median time between studies, 10 months). RESULTS: Hypointense lesions were detected in 24 subjects on SWI sequences and in 19 subjects on GRE sequences. More lesions were seen on SWI than on GRE (p = 0.006). Four patients had no detectable lesions. The minimal period from irradiation to first lesion detection was 14 months. Cavernomas larger than 3 mm were detected in 14 subjects by both GRE and SWI. None of the subjects had symptoms related to cavernomas. CONCLUSIONS: The sensitivity of SWI in the detection of hypointense lesions in patients after whole-brain irradiation is significantly higher than that of the GRE sequence. It appears that almost all subjects eventually develop small hypointense lesions after radiotherapy, and some of them progress to cavernous malformations. The clinical significance of the increased sensitivity of SWI in this group of patients is not entirely certain.