The relationship between bone health and type of intracranial internal carotid calcifications in patients with ischemic stroke.

INTRODUCTION: Vascular calcifications, primarily in the aorta and its proximal branches, are commonly observed among subjects with impaired bone health. In this study, we sought to determine if a comparable association holds true for the calcifications in the intracranial internal carotid arteries (IICA), in general and also for particular calcification patterns. METHODS: A consecutive series of ischemic stroke patients were prospectively enrolled into the study, where computed tomography angiography source images were used to determine the presence and type of IICA calcifications, and dual-energy X-ray absorptiometry was used to determine the bone mineral density in the left femoral neck region. IICA calcifications were categorized as none, intimal, medial, and mixed types based on previously validated classification schemes. Their relationships with femoral bone T-scores were evaluated by bivariate and multivariate analyses. RESULTS: Femoral neck T-score was highest among patients without any vascular calcifications (n=65), when compared to the bone density measures among patients with any type of calcification (n=185) (p<0.001). After adjustment for age, gender, vascular risk factors, and serum biomarkers related to bone health, the T-score remained significantly associated only with the pattern of intimal calcification [OR 0.63 (0.42 - 0.95), p=0.028]. CONCLUSIONS: Our findings suggest that the intracranial vasculature, in particular the internal carotid arteries, is not immune to the interplay between suboptimal bone health and vascular calcifications. This association was most robust for an intimal type of IICA calcification pattern, while no such relationship could be demonstrated for other types of vascular calcifications.

The Outcome of COVID-19 in Pediatric-Onset Multiple Sclerosis Patients.

BACKGROUND: The pathogenesis of multiple sclerosis (MS) involves immune-mediated mechanisms, and disease-modifying therapies (DMTs) administered in MS have immunomodulatory effects. The concern about MS patients' susceptibility to coronavirus disease 2019 (COVID-19) has prompted several studies based on clinical observations and questionnaires. Information about COVID-19 in pediatric-onset multiple sclerosis (POMS) is scarce. The objective of this study was to collect information on the experience of POMS patients with COVID-19 during the pandemic. METHODS: This cross-sectional study was conducted with POMS patients diagnosed at Hacettepe University Pediatric Neurology Department and under 23 years of age between October 1 and December 31, 2021. Those who experienced COVID-19 or had a history of contact and were found seropositive for COVID-19 were evaluated for the severity of COVID-19, disability, treatment status, and comorbidities. RESULTS: Among the 101 POMS patients, 13 reported having had COVID-19 and five were exposed and seropositive but clinically asymptomatic. Of these 18 patients, 14 were ≤18 years of age at the time of the study. All 13 patients (72%) reported mild symptoms without hospitalization or respiratory support. Four of 18 had a neurological disability (Expanded Disability Status Scale [EDSS] scores ranging between 1 and 7.5), while the remaining had a score of 0. The outcome of COVID-19 was not affected by DMTs, neurological disabilities, and comorbidities. CONCLUSIONS: In this single-center POMS series, the small subgroup of patients who had contacted the SARS-CoV-2 virus or developed COVID-19 had reported no or mild symptoms. This may be partly related to the infrequent use of rituximab in this group. Our results corroborate those in adult-onset MS where no increased risk is reported for patients whose EDSS scores are <6 and who are not on B cell-depleting DMTs. Although less frequently than in adult MS, immunosuppressive DMTs may be needed in POMS; therefore, the importance of appropriate vaccination is to be underlined.

Apparent diffusion coefficient signature of ischemic tissue predicts neurological progression in isolated pontine infarcts.

Background: Early neurological deterioration is encountered in up to a third of patients with isolated pontine infarcts. A limited number of clinical and imaging features have been suggested as predictors of neurological progression in this setting. In this study, we assessed whether quantitative apparent diffusion coefficient (ADC) measurements within the ischemic pontine region could be used as a radiomic feature to forecast clinical deterioration. Methods: We calculated the mean ADC value of ischemic voxels within the ischemic region and normalized them to the contralateral non-ischemic tissue (relative ADC, rADC) in patients with isolated pontine infarcts. This imaging signature was then compared among patients with neurological progression (n = 21) and a propensity matched cohort of non-progressors (n = 42), together with other clinical and imaging features in bivariate and multivariate statistical models. Results: The rADCmean was significantly lower among patients with progression (p = 0.008). Female gender and extension of the ischemic lesion to the ventral pontine surface were other features significantly associated with progression. The association between rADCmean and progression persisted in multivariate models with an odds ratio of 13.7 (95% CI 2.6-72.8; p = 0.002) for progression among patients with rADCmean ≤ 0.67 in their ischemic tissue. The probability for worsening was 80% among patients who had an ischemic lesion extending to the ventral pontine surface with a mean rADC ≤ 0.67. Conclusion: The mean rADC value within the ischemic lesion is closely related with early neurological deterioration in patients with isolated pontine infarcts.

Intracerebral hemorrhage volume estimation: Is modification of the ABC/2 formula necessary according to the hematoma shape?

OBJECTIVE: We studied the proposal to modify the ABC/2 formula to ABC/3 for irregular-shaped intracerebral hematoma (ICH) volume estimation. PATIENTS AND METHODS: The volume of 133 ICHs were estimated with Kwak's (simplified C; all slices with hemorrhage are considered equal), Kothari's (weighted C) and coronal (reformatted C; measuring C directly on coronal reformatted images) ABC/2 methods, and compared with computer-assisted planimetric measurements. The accuracy, precision and correlation of three ABC/2 methods and their ABC/3 modifications were determined in smooth (Barras' group 1 or 2) and irregular (Barras' group 3-5) shaped ICHs. RESULTS: As the hematoma size increases, the shape becomes irregular. In all hematomas, both smooth (n = 81) and irregular (n = 52) shaped, Kothari's ABC/2 formula provided the closest result to the planimetric measurement, with an underestimation of 1.77 mL, and 10.2% difference on average. Kothari's ABC/2 disclosed the best correlation (Lin's coefficient=0.9622) regardless of ICH shape. When simplified-ABC/2 method was modified as ABC/3, volume estimation accuracy increased (Correlation coefficient increased from 0.838 to 0.915) for irregular hematomas; however, despite this improvement the accuracy remained below the Kothari's ABC/2 (not ABC/3) method. Neither reformatted coronal ABC/2 nor its ABC/3 modification provided any advantage over ABC/x formulas with slice counting. CONCLUSION: Kothari's ABC/2 method is a valid method for estimation of ICH volume for both regular and irregular shaped hematomas. Simplified (Kwak's) ABC/2 or coronal ABC/2, or their /3 counterparts do not provide additional advantage.

Stroke Mechanism in COVID-19 Infection: A Prospective Case-Control Study.

BACKGROUND: The characteristics and pathophysiological mechanisms involved in acute ischemic stroke in patients with COVID-19 infection have not been fully clarified. We prospectively studied the phenotypic and etiological features of acute stroke occurring in COVID-19 infection. PATIENTS & METHODS: Within nine months starting from April-2020, the presence of COVID-19 infection was determined by thoracic CT and SARS-CoV-2 PCR in all acute stroke cases managed in a single tertiary center. Consecutive and prospective data on vascular risk factors/comorbidities, in-hospital quality metrics, discharge outcomes, etiological subclassification and blood markers of thrombosis / inflammation were compared in 44 COVID-19 positive cases (37 acute ischemic stroke, 5 TIA, 2 intracerebral hematoma) and 509 COVID-19 negative patients (355 ischemic, 105 TIA, 44 hematoma and 5 stroke mimic). RESULTS: COVID-19 positive patients had more severe strokes, delayed hospital admission, longer hospital stay, higher mortality rates, but had similar vascular risk factors/comorbidities frequency, thrombolysis/thrombectomy utilization rates, metrics, and stroke etiological subtype. They had significantly higher CRP, fibrinogen, ferritin, leukocyte count and lower lymphocyte count. No difference was detected in aPTT, INR, D-dimer, platelet, hemoglobin, homocysteine levels and ANA, anti-dsDNA antibody and ENA panel positivity rates. Anti-phospholipid antibodies have been studied in 70% of COVID-19 positive and all cryptogenic patients, but were never found positive. Tests for coagulation factor levels and hereditary thrombophilia did not show major thrombophilia in any of the stroke patients with COVID-19. CONCLUSION: We documented that there is no significant difference in etiological spectrum in acute stroke patients with COVID-19 infection. In addition, cryptogenic stroke and antiphospholipid antibody positivity rates did not increase.

The dynamics of hematoma surface regularity and hematoma expansion in acute intracerebral hemorrhage.

The clarification of factors that contribute to hematoma expansion in the setting of intracerebral hemorrhage (ICH) and the relevant physical dynamics are implemental for development of management strategies. Herein, we assessed the interplay between hematoma expansion and surface regularity of intracerebral bleeds. To do so, hematoma contours were outlined on admission and follow-up computed tomography (CT) studies using semi-automated thresholding algorithms in 133 ICH patients. Hematoma volume, surface area and surface regularity [SR=6√πvolumesurfacearea3, ranging from 0 (very irregular surface) to 1 (perfectly regular surface suggestive of 3D spherical structure)] were determined by 3D Slicer software (www.slicer.org). Hematoma growth was defined as ≥33% relative growth, or ≥ 6 mL absolute growth. Our results are as follows: The median (IQR) hematoma volume was 14.2 (6.0-34.9) mL on admission CT obtained 2.4 (1.5-4.4) hours after symptom onset; the mean ± SD SR value was calculated as 0.62 ± 0.14. Patients who underwent imaging at earlier time points were more likely to have higher SR (r = 0.18; p = 0.035). The median hematoma volume at follow-up, 35 (21-47) hours after the initial scan, was 19.7 (6.9-44.4) mL. The regularity index decreased significantly at this time point to 0.58 ± 0.13 (p < 0.001) and corresponding increase of surface irregularity was independent of change in hematoma volume. Baseline hematoma volume, INR, and time to initial imaging were significant predictors of hematoma expansion. In conclusion, our findings suggest that hematomas evolve into more irregular 3D shapes during follow-up. These observations are consistent with the 'domino' hypothesis put forward for ICH expansion.