Medial temporal lobe atrophy is underreported and may have important clinical correlates in medical inpatients

BACKGROUND The diagnostic workup in dementia includes brain imaging with reading focussed on signs of cerebrovascular and neurodegenerative disease. We hypothesised that these findings may be underreported in hospital patients, where imaging is often performed to rule out obvious pathology such as haemorrhage. In this study, we review cranial computed tomography (CT) in medical inpatients for white matter changes and atrophy. Our aim was to determine the clinical relevance of such findings and to what extent they were underreported. METHODS Records from 200 inpatients aged over 60 years, who had been subjected to MMSE (mini-mental state examination) and CDT (clock-drawing test), were reviewed for cranial CT. Transverse and coronal slices were reassessed using visual rating scales regarding white matter changes (WMC), global cortical atrophy (GCA) and medial temporal lobe atrophy (MTA). Findings were compared with the original radiology reports and cognitive test results. RESULTS Cranial CT had been performed in 94 of 200(47 %) patients. Of these, 58(62 %) had abnormal WMC, 35(37 %) abnormal GCA and 34(36 %) abnormal MTA. All three findings had associations with cognitive test results. Abnormal MTA was associated with lower results on the overall score on MMSE and on orientation, memory and language items. All three measurements were underreported in the original radiology reports; none of the 34 patients with abnormal MTA had been reported originally. CONCLUSIONS Signs of neurodegenerative disease, especially MTA, were highly underreported in cranial CT scans performed in medical inpatients. At the same time, MTA seemed to hold the most important clinical correlates. Our results suggest that MTA should be reported more regularly in this setting.