Abstract
AimTo evaluate the use the distance between the adjacent septal nuclei as a surrogate marker of septal area atrophy seen in Alzheimer's disease (AD).Materials & MethodsInterseptal distance (ISD) was measured, blind to clinical details, in 250 patients who underwent computed tomography (CT) of the brain at University Hospital of Wales. Clinical details including memory problem history were retrieved. An ISD cut-off value that discriminated those with and without memory symptoms was sought. ISD measurements were also made in 20 AD patients. To test both the method and the defined cut-off, measurements were then made in an independent cohort of 21 mild cognitive impairment (MCI) patients and 45 age-matched healthy controls, in a randomised and blinded fashion.ResultsISD measurement was achieved in all patients. In 28 patients with memory symptoms, the mean ISD was 5.9 mm compared with 2.3 mm in those without overt symptoms (p=0.001). The optimum ISD cut-off value was 4 mm (sensitivity 85.7% and specificity 85.8%). All AD patients had an ISD of >4 mm (mean ISD= 6.1 mm). The mean ISD for MCI patients was 3.84 mm compared with 2.18 mm in age-matched healthy controls (p=0.001). Using a 4 mm cut-off correctly categorised 10 mild cognitive impairment patients (47.6%) and 38 healthy controls (84.4%).ConclusionISD is a simple and reliable surrogate measurement for septal area atrophy, applicable to CT and magnetic resonance imaging (MRI). It can be used to help select patients for further investigation.
Highlights
Details recorded from the request forms including patient’s age, any known diagnosis of Alzheimer’s disease (AD), dementia, mild cognitive impairment (MCI), history of confusion or chronic memory problems as well as excess alcohol use were recorded after blinded measurement of the interseptal distance (ISD) of these patients
The septal nuclei could not be located confidently in five patients as the anterior cerebral artery could not be separated from the nuclei. To compensate for this problem, after the independent assessment of ISD by the neuroradiologist and trainee, the images from these 11 patients were reviewed together and a reasonable ISD was agreed for each case
The reproducibility analysis showed an inter-rater coefficient of variation of 10.5% and an intraclass correlation coefficient of 0.96 when the measurements of ISD were compared between the neuroradiologist and trainee
Summary
L. Gan, Department of Neuroradiology, University Hospital of Wales, Cardiff, UK. Alzheimer’s disease (AD) is the commonest cause of dementia and it affects around 5.4 million people in the US.[1] Patients typically present with progressive memory impairment and involvement of other cognitive domains or skills, which impair social function and activities of daily living.[2] The diagnosis of AD is often difficult especially near the onset of symptoms.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
