Clinical Predictors of Abnormal Findings on Urgent CT Brain Scans in Adult Non-trauma Patients at a Tertiary Hospital

Abstract

Background: Computed tomography (CT) scan of the brain is widely used for assessing various neurological conditions and remains the imaging modality of choice in acute and emergency settings. However, CT brain in non-traumatic patients has been reported to have a low diagnostic yield of about 15%. This study aims to identify the prevalence of abnormal urgent CT brain performed in non-trauma adult patients in our centre and the clinical predictors associated with the significant abnormal findings. Methods: This is an analytical cross-sectional study of urgent CT brains in patients aged 18 years or older who did not have head trauma or known intracranial pathology in Sultan Ahmad Shah Medical Centre @IIUM (SASMEC) from 1st January 2019 to 31st December 2020. A universal sampling of all urgent CT brain examinations done during the study period were traced from the Radiology Information System (RIS). Exclusion criteria include patient’s younger than 18 years old, patients with history of head trauma and patients with known history of any intracranial pathologic process. Results: A total of 771 cases fulfilled the inclusion criteria. The majority of the urgent CT brain examinations for non-trauma adult patients were from the Emergency Department, which contributed to 600 cases (77.8%). Our study showed abnormal CT brain findings in 503 patients (65.2%). Our study showed age (adjusted odds ratio: 1.03; 95% confidence interval: 1.01 – 1.04; p-value: < 0.001), headache (adjusted odds ratio: 1.87; 95% confidence interval: 1.17 – 3.00; p-value: 0.009), focal neurological deficit (adjusted odds ratio 0.387; 95% confidence interval: 0.25 – 0.59; p-value: < 0.001), deranged blood pressure (adjusted odds ratio: 0.71, 95% confidence interval CI: 0.55-0.59; p-value: 0.042) and known malignancy (adjusted odds ratio 2.14; 95% CI: 1.02-4.49, p-value: 0.043) are the clinical predictors of these abnormal CT brains. Conclusion: Our study shows positive (abnormal) findings in 65.2% of urgent CT brain examinations among non-trauma adult patients. This suggests good selective criteria by our clinicians in using urgent CT brain scan for neurological assessment in adult non-trauma patients. Age, headache, focal neurological deficits, deranged blood pressure and known malignancy are the significant clinical predictors for these abnormal CT brains.