Optimising neuroimaging effectiveness in a district general hospital

Diagnostic accuracy in neurology frequently depends on clinical assessment and neuroimaging interpretation. We assessed neuroimaging discrepancy rates in reported findings between general radiologists and neuroradiologists among patients from a district general hospital (DGH). A neuroradiologist's report was sought on selected DGH patients over 28 months. Pre-planned outcomes included comparisons of primary findings (main diagnosis or abnormality), secondary findings (differential diagnoses and incidental findings) and advice from neuroradiologists for further investigations. A total of 233 patients (119 men and 114 women), mean age 47.2 (SD 17.8) years were studied: 43 had a computed tomography (CT) brain scan only, 37 had CT and magnetic resonance imaging (MRI) scans and 153 had only MRI scans. Discrepancies in the primary diagnosis/abnormality were identified in 33 patients (14.2%). This included 7 of 43 patients (16.3%) who had a CT brain scan as their only neuroimaging. Secondary outcomes differed in 50 patients (21.5%). Neuroradiologists recommended further neuroimaging for 29 patients (12.4%). The most common discrepancies in the primary diagnosis/abnormality were misinterpreting normal for hippocampal sclerosis and missed posterior fossa lesions. There was no evidence of temporal changes in discrepancy rates. Selecting CT and MR neuroimaging studies from general hospitals for reviewing by neuroradiologists is an important and effective way of optimising management of neurological patients.