Positron emission tomography (PET) with 15O-gas for quantifying cerebral blood flow (CBF) and oxygen metabolism is the gold standard for assessing hemodynamics in ischemic cerebrovascular disease. However, conventional 15O-gas PET methods do not provide information on regional arrival timing, a hemodynamic parameter typically measured using computed tomography (CT) perfusion with contrast media. This study demonstrated that 15O-gas PET with a state-of-the-art clinical PET scanner and optimized analysis can generate arrival time maps. In this retrospective study of ten patients with unilateral stenosis or occlusion of the major arteries, we compared PET-derived arrival time maps with CT perfusion Tmax maps. In PET with short inhalation of [15O]-CO2 gases, dynamic images were reconstructed with 2-sec temporal resolution, followed by weighted least-squares fitting of one-tissue compartment models, with or without the contributions from vascular components. PET arrival time maps were visually comparable to CT perfusion Tmax maps regarding the spatial extent of delayed brain regions, with less noise and higher image quality when using the model without the vascular components. Region-of-interest analyses showed good correlations between the two modalities: correlation coefficients of 0.834 for absolute values and 0.718 for ipsilateral-to-contralateral differences, respectively, indicating that 15O-gas PET can quantitatively measure the arrival time with reasonable accuracy. The present method generates arrival-time maps with 15O-gas PET by applying optimized kinetic analysis to dynamic [15O]-CO2 images acquired using a state-of-the-art, high-sensitivity clinical PET scanner. Additional arrival time information for conventional PET parameters of CBF and oxygen metabolism may facilitate a more comprehensive understanding of the hemodynamic status in cerebrovascular steno-occlusive diseases.
BACKGROUND:A mild malformation of cortical development (MCD) with oligodendroglial hyperplasia and epilepsy (MOGHE) is characterized by increased Olig2-positive atypical cells in the white matter and is associated with drug-resistant intractable epilepsy, typically the frontal and temporal lobes. MOGHE is a newly classified subtype of focal cortical dysplasia associated with epilepsy, according to the latest International League Against Epilepsy guidelines. There have been no reports of MOGHE without epilepsy and associated with extensive lesions. OBSERVATIONS:A 31-year-old man was incidentally diagnosed with an extensive right cerebral hemispheric lesion on MRI. Pathological examination of the biopsy sample showed no evidence of an invasive tumor but revealed an increase in Olig2-positive cells, consistent with MOGHE. Sanger sequencing showed no IDH1/2, histone H3 TERTpromoter, or SLC35A2 mutations. Electroencephalography showed no evidence of epilepsy. LESSONS:This case suggests the existence of a condition with similar histological findings to MOGHE but without epilepsy. The authors propose naming this condition "mild malformation of cortical development with oligodendroglial hyperplasia and no epilepsy." https://thejns.org/doi/10.3171/CASE24827.
Rationale: Neurogenic pulmonary edema (NPE) is one of the under-diagnosed clinical syndromes secondary to central nervous system injury, as represented by aneurysmal subarachnoid hemorrhage (SAH). We have recently presented that NPE has two distinct pathophysiologic mechanisms, i.e., permeability and hydrostatic edema. Glycocalyx shedding from the lung endothelial layer has shown to be associated with respiratory physiology and clinical outcome in critical care patients after ARDS, but its relationship with NPE is unknown. Objective: To test the hypothesis that the serum biomarker of glycocalyx degradation is higher in permeability edema than hydrostatic edema, we measured serum sindecan-1 levels in patients suffering from NPE after SAH, and further assessed its relationship with intrathoracic volumetric parameters and impact on outcome. Methods: Based on medical records and biological sample storages in our SAH database (2007-2022), serum frozen samples of patients diagnosed with NPE were detected. Syndecan-1 concentrations were measured by ELISA and compared their levels between 2 types of edema classified by transpulmonary thermodilution (TPTD)-based volumetric parameters, and further compared with clinical outcome measures (lengths of ventilation and ICU stay, and functional outcome assessed functionally by modified Rankin Scale score at 3 months). Results: Of 40 patients included, 24 with hydrostatic edema and 16 with permeability edema. Serum syndecan-1 levels were significantly higher in patients with permeability edema than those with hydrostatic edema, which was positively correlated with TPTD-derived pulmonary vascular permeability index (PVPI) and extravascular lung water/global end-diastolic index on initial measurements. Although there were no statistically significant differences in length of ventilator-free days or ICU stay, syndecan-1 was inversely associated with good functional outcome (r=-0.52; p=0.03). Multivariate regression analysis across all NPE cases showed that syndecan-1 and PVPI levels were independent risks for worse outcome. Conclusions: These findings suggest that serum syndecan-1 is a valuable biomarker and potential mediator of lung injury in patients with NPE. Early recognition of NPE in conjunction with volumetric parameters of lung vascular permeability may be a key to achieve good clinical outcomes.
μ-opioid receptor (MOP) plays a critical role in mediating opioid analgesic effects. Genetic variations, particularly those in the MOP gene (Oprm1), significantly influence individual variations in opioid efficacy and side effects across species, highlighting the need for pharmacogenomic research in human and veterinary contexts. This study aimed to identify single-nucleotide variations (SNVs) within Oprm1 in 100 cats of various breeds. Oprm1 spans over 170 kb and consists of five exons that combine to yield three splice variants in the cat Ensembl database. Among these variants, Oprm1-202 is an ortholog of the MOR-1 transcript, which is the most abundant in humans and mice. Oprm1-202 shares 92% and 87% coding sequences (CDS) and 96% and 94% amino acid sequence identity with human and mouse MOR-1, respectively. Phylogenetic trees were constructed from the CDS and amino acid sequences of nine species, including humans, cats, and mice. Both the CDS and amino acid sequences of MOP in cats showed phylogenetic development closer to that of primates than of rodents. Four SNVs were identified in the CDS of Oprm1. One SNV was located in exon 1 and the other three in exon 2 of Oprm1, all of which were synonymous substitutions. Although synonymous mutations generally have a limited functional impact, they may influence splicing and receptor expression. Further research is required to assess the effects of these SNVs on opioid efficacy, receptor expression, and analgesic responses across breeds, considering the potential breed-specific genetic factors in cat species.
