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Background and Purpose: To identify the qualitative and quantitative contributions of conventional risk factors for occurrence of ischemic stroke and its key pathophysiologic subtypes among West Africans. Methods: The SIREN (Stroke Investigative Research and Educational Network) is a multicenter, case-control study involving 15 sites in Ghana and Nigeria. Cases include adults aged ≥18 years with ischemic stroke who were etiologically subtyped using the A-S-C-O-D classification into atherosclerosis, small-vessel occlusion, cardiac pathology, other causes, and dissection. Controls were age- and gender-matched stroke-free adults. Detailed evaluations for vascular, lifestyle, and psychosocial factors were performed. We used conditional logistic regression to estimate adjusted odds ratios with 95% CI. Results: There were 2431 ischemic stroke case and stroke-free control pairs with respective mean ages of 62.2±14.0 versus 60.9±13.7 years. There were 1024 (42.1%) small vessel occlusions, 427 (17.6%) large-artery atherosclerosis, 258 (10.6%) cardio-embolic, 3 (0.1%) carotid dissections, and 719 (29.6%) undetermined/other causes. The adjusted odds ratio (95% CI) for the 8 dominant risk factors for ischemic stroke were hypertension, 10.34 (6.91–15.45); dyslipidemia, 5.16 (3.78–7.03); diabetes, 3.44 (2.60–4.56); low green vegetable consumption, 1.89 (1.45–2.46); red meat consumption, 1.89 (1.45–2.46); cardiac disease, 1.88 (1.22–2.90); monthly income $100 or more, 1.72 (1.24–2.39); and psychosocial stress, 1.62 (1.18–2.21). Hypertension, dyslipidemia, diabetes were confluent factors shared by small-vessel, large-vessel and cardio-embolic subtypes. Stroke cases and stroke-free controls had a mean of 5.3±1.5 versus 3.2±1.0 adverse cardio-metabolic risk factors respectively ( P Conclusions: Traditional vascular risk factors demonstrate important differential effect sizes with pathophysiologic, clinical and preventative implications on the occurrence of ischemic stroke among indigenous West Africans.

Background Annotation and Image Markup on ClearCanvas Enriched Stroke–phenotyping Software (ACCESS) is a novel stand-alone computer software application that allows the creation of simple standardized annotations for reporting brain images of all stroke types. We developed the ACCESS application and determined its inter-rater and intra-rater reliability in the Stroke Investigative Research and Educational Network (SIREN) study to assess its suitability for multicenter studies. Methods One hundred randomly selected stroke imaging reports from 5 SIREN sites were re-evaluated by 4 trained independent raters to determine the inter-rater reliability of the ACCESS (version 12.0) software for stroke phenotyping. To determine intra-rater reliability, 6 raters reviewed the same cases previously reported by them after a month of interval. Ischemic stroke was classified using the Oxfordshire Community Stroke Project (OCSP), Trial of Org 10172 in Acute Stroke Treatment (TOAST), and Atherosclerosis, Small-vessel disease, Cardiac source, Other cause (ASCO) protocols, while hemorrhagic stroke was classified using the Structural lesion, Medication, Amyloid angiopathy, Systemic disease, Hypertensive angiopathy and Undetermined (SMASH-U) protocol in ACCESS. Agreement among raters was measured with Cohen's kappa statistics. Results For primary stroke type, inter-rater agreement was .98 (95% confidence interval [CI], .94-1.00), while intra-rater agreement was 1.00 (95% CI, 1.00). For OCSP subtypes, inter-rater agreement was .97 (95% CI, .92-1.00) for the partial anterior circulation infarcts, .92 (95% CI, .76-1.00) for the total anterior circulation infarcts, and excellent for both lacunar infarcts and posterior circulation infarcts. Intra-rater agreement was .97 (.90-1.00), while inter-rater agreement was .93 (95% CI, .84-1.00) for TOAST subtypes. Inter-rater agreement ranged between .78 (cardioembolic) and .91 (large artery atherosclerotic) for ASCO subtypes and was .80 (95% CI, .56-1.00) for SMASH-U subtypes. Conclusion The ACCESS application facilitates a concordant and reproducible classification of stroke subtypes by multiple investigators, making it suitable for clinical use and multicenter research.

Background: High resolution chest computed tomography (HRCT) is an established imaging modality that accurately assesses disease processes that are non-specific on conventional chest radiography. Chest Computed Tomography (CT) has proven invaluable in the evaluation of various diseases of the chest providing precise diagnosis that have great impact on the course of management. In this study, our aim is to evaluate the spectrum of radiological findings in all patients that had chest CTs at a tertiary health Institution in a developing Country. Method: This is a 6-year retrospective study of all patients that had Chest CT from 2009 till 2015. All patient data were retrieved and their Chest CT images reviewed and radiological findings and diagnosis documented. Results: Age range of patients was 1 - 84 years with a mean of 52.36 ± 22.9 years. Ten patients were children (12%). There were more males 53 (63.1%) than females 31 (36.9%) in the study. Referral for imaging was predominantly from internal medicine 33 (47.1%) and Surgery 27 (38.6%) departments. Most of the patients, 53 (63.1%) did not have previous chest radiographs. Consolidative changes were the most common parenchymal finding (77.4%). Few mediastinal masses were found in the study population. CT angiography constituted only 10.7% of all chest CTs done in adults. Conclusion: Few chest CT evaluations are performed compared to CTs of other parts of the body done in the same period. Chest CT is generally under-utilized even in a tertiary institution. There is a need to educate chest physicians on the role and advantages of CT use for the management of their patients.

Background It is crucial to assess genomic literacy related to stroke among Africans in preparation for the ethical, legal and societal implications of the genetic revolution which has begun in Africa. Objective To assess the knowledge, attitudes and practices (KAP) of West Africans about stroke genetic studies. Methods A comparative cross-sectional study was conducted among stroke patients and stroke-free controls recruited across 15 sites in Ghana and Nigeria. Participants' knowledge of heritability of stroke, willingness to undergo genetic testing and perception of the potential benefits of stroke genetic research were assessed using interviewer-administered questionnaire. Descriptive, frequency distribution and multiple regression analyses were performed. Results Only 49% of 2029 stroke patients and 57% of 2603 stroke-free individuals knew that stroke was a heritable disorder. Among those who knew, 90% were willing to undergo genetic testing. Knowledge of stroke heritability was associated with having at least post-secondary education (OR 1.51, 1.25–1.81) and a family history of stroke (OR 1.20, 1.03–1.39) while Islamic religion (OR=0.82, CI: 0.72–0.94), being currently unmarried (OR = 0.81, CI: 0.70–0.92), and alcohol use (OR = 0.78, CI: 0.67–0.91) were associated with lower odds of awareness of stroke as a heritable disorder. Willingness to undergo genetic testing for stroke was associated with having a family history of stroke (OR 1.34, 1.03–1.74) but inversely associated with a medical history of high blood pressure (OR = 0.79, 0.65–0.96). Conclusion To further improve knowledge of stroke heritability and willingness to embrace genetic testing for stroke, individuals with less formal education, history of high blood pressure and no family history of stroke require targeted interventions.

Background: Low-field (LF) magnetic resonance imaging (MRI) is a technology that is widely used in resource-limited settings for clinical imaging. The images produced, even though of low resolution with noise and artefacts, provide valuable information and guidance for patient assessment and treatment. This study shows a spectrum of MRI artefacts that affect image quality during routine clinical neuroradiology practice using LF MRI in a Nigerian hospital and suggests ways to avoid them. Materials and Methods: We retrospectively reviewed brain and spine MRI studies performed on a 0.36T MagSense 360 (Mindray, China) open MRI at our hospital over a 2-year period to identify image artefacts. About 90% of MRI studies performed at our facility during the study period were neuroimaging. The pattern and distribution of artefacts that featured during imaging were described and illustrative cases demonstrated highlighting their causes and ways to avoid or limit them. Results: Of 936 brain and spine cases evaluated, 506 (54.1%) had artefacts with 369 (72.9%) seen in the brain. Truncation/Gibbs (37.6%) and motion (20.6%) were the most common artefacts in the series, seen most commonly in T2-weighted images. There was no significant difference in the proportion of artefacts between adults and children (P = 0.736). Conclusion: Artefacts are relatively common in neuroimaging with LF MRI and may potentially degrade image quality and interfere with accurate radiological reporting and diagnosis. Improving the recognition of LF MRI artefacts may assist imaging practitioners to avoid or limit their effect on image quality and interpretation.

Background: Thickness and texture of the squamous temporal bones (STBs) are the two main patient factors that determine the outcome of transtemporal transcranial Doppler ultrasound. The aim of this study was to determine the thickness and texture of the STB as well as their association with biodemographic characteristics in a tertiary hospital in Southwest Nigeria. Material and Methods: Cranial computed tomography (CT) images of 142 adults acquired on a 64-slice multi-detector Toshiba Aquilion scanner were retrospectively evaluated for the thickness and texture of the bilateral STB at the expected location of the temporal acoustic window on a ClearCanvas® Workstation. Associations of thickness and texture of the STB with biodemographic data were determined by statistical analysis at P Results: There were 79 male (55.6%) participants and the overall mean age was 51 ± 17.3 years (49 ± 16.1 years in males and 53.4 ± 18.5 years in females). Mean thickness of the 284 STB was 3.21 ± 1.11 mm (range 1.2–8.7 mm), which was thicker on the left (3.3 ± 1.2 mm) than the right (3.1 ± 1.0 mm, P = 0.001). Thickness of STB showed significant increase (P Conclusion: Thickness of the squamous temporal bone varied significantly with age but not with gender, and the temporal squama were largely of a homogeneous texture. Overall, the important patient factors appear favorable for transtemporal cranial ultrasound in the majority of our participants.