Association between the high risk for obstructive sleep apnea and intracranial carotid artery calcification in patients with acute ischemic stroke.

PURPOSE: Obstructive sleep apnea (OSA) is an independent risk factor for stroke. Furthermore, intracranial carotid artery calcification (ICAC) is a marker for subclinical atherosclerosis and future cardiovascular events. We investigated the association between the high risk for OSA and ICAC in patients with acute ischemic stroke. METHODS: We retrospectively investigated 73 patients who were admitted to the hospital with acute ischemic stroke in the internal carotid artery (ICA) territory due to large-artery atherosclerosis. The risk for OSA was assessed using the Berlin Questionnaire, and patients were classified into low-risk (LR-OSA) and high-risk groups (HR-OSA). We compared the burden of ICAC between the two groups. Univariable and multivariable analyses were conducted to investigate the association of high risk for OSA with the presence of calcium in intracranial ICA. RESULTS: The HR-OSA group of 35 patients (48%) was significantly older and had a higher rate of hypertension and diabetes mellitus than the LR-OSA group. The HR-OSA group had more frequent ICAC (92% vs. 63%, p < 0.001), higher Agatston score (162.0 vs. 8.5, p < 0.001), and greater total volume of ICAC (261.2 mm3 vs. 20.1 mm3, p < 0.001) in the intracranial ICA. Presence of calcium in symptomatic intracranial ICA was positively correlated with age (odds ratio, OR, 1.432; 95% confidence interval, CI, 1.098-1.868) and HR-OSA (OR, 18.272; 95% CI, 0.500-668.401) in multivariable logistic regression analysis. CONCLUSIONS: This study showed that the presence of calcium in symptomatic intracranial ICA was related to high risk for OSA in patients with acute ischemic stroke.

Differentiation between spinal cord diffuse midline glioma with histone H3 K27M mutation and wild type: comparative magnetic resonance imaging.

PURPOSE: Diffuse midline glioma with histone H3 K27M mutation is a new entity described in the 2016 update of the World Health Organization Classification of Tumors of the Central Nervous System. The purpose of this study was to evaluate the clinical and imaging characteristics to predict the presence of H3 K27M mutation in spinal cord glioma using a machine learning-based classification model. METHODS: A total of 41 spinal cord glioma patients consisting of 24 H3 K27M mutants and 17 wild types were enrolled in this retrospective study. A total of 17 clinical and radiological features were evaluated. The random forest (RF) model was trained with the clinical and radiological features to predict the presence of H3 K27M mutation. The diagnostic ability of the RF model was evaluated using receiver operating characteristic (ROC) analysis. Area under the ROC curves (AUC) was calculated. RESULTS: MR imaging features of spinal cord diffuse midline gliomas were heterogeneous. Hemorrhage was the only variable that was able to differentiate H3 K27M mutated tumors from wild-type tumors in univariate analysis (p = 0.033). RF classifier yielded 0.632 classification AUC (95% CI, 0.456-0.808), 63.4% accuracy, 45.8% sensitivity, and 88.2% specificity. CONCLUSION: Our findings indicate that clinical and radiological features are associated with H3 K27M mutation status in spinal cord glioma.

Prediction of the success of thyroid remnant ablation using preablative 99mTc pertechnetate scintigraphy and postablative dual 131I scintigraphy.

OBJECTIVE: The aim of this study was to predict the success of 131I ablation using preablative 99mTc pertechnetate salivary scintigraphy and a postablative dual 131I scan in differentiated thyroid cancer (DTC). PATIENTS AND METHODS: A total of 168 DTC patients who underwent 131I ablation with preablative salivary scintigraphy and a postablative dual (early and delayed) 131I scan were enrolled. For salivary scintigraphy, the thyroid remnant uptake was visually assessed. For the dual 131I scan, the thyroid remnant to background uptake ratios (TBRs) on early and delayed scans were measured and the percentage change in TBR (TBRΔ) was calculated. RESULTS: Thyroid remnant uptake was seen in 69 (41%) patients on salivary scintigraphy and in 162 (96%) patients on the dual 131I scan. The success rate of ablation was higher in patients with negative remnant uptake on salivary scintigraphy (86%) than in patients with positive remnant uptake (58%, P=0.0001). The success rate of ablation was 100% in patients with no remnant uptake on both salivary scintigraphy and the dual 131I scan. The success rate of ablation was higher in patients with TBRΔ 0 or more than in patients with TBRΔ less than 0, irrespective of remnant uptake on salivary scintigraphy (91 vs. 70%, P=0.03, for patients without remnant uptake on salivary scintigraphy; 74 vs. 48%, P=0.05, for patients with remnant uptake on salivary scintigraphy). CONCLUSION: The success of thyroid remnant ablation in DTC can be predicted by the presence of remnant uptake on preablative 99mTc pertechnetate scintigraphy and change in remnant uptake on the postablative dual 131I scan.

A case of septic pulmonary embolism associated with renal abscess mimicking pulmonary metastases of renal malignancy.

We report the case of a 46-year-old woman with acute febrile symptom who had multiple pulmonary nodules and a renal mass. She underwent (18)F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) to find a hidden malignancy and the cause of her fever. FDG PET/CT images demonstrated a renal mass and multiple lung nodules with intense FDG uptake, which was suspicious of a renal malignancy with multiple pulmonary metastatic lesions. CT-guided biopsies of the pulmonary and renal lesions only showed chronic inflammatory infiltrates without evidence of malignancy. She was diagnosed with septic pulmonary embolism from a renal abscess. One month after antibiotic treatment, the follow-up chest and abdomen CT showed improvement of the lung and renal lesions. This is the first case demonstrating the FDG PET/CT finding of septic pulmonary embolism associated with renal abscess in the published literature.