Memory impairment in Amyloidβ-status Alzheimer's disease is associated with a reduction in CA1 and dentate gyrus volume: In vivo MRI at 7T

INTRODUCTION

In Alzheimer's disease (AD), early diagnosis facilitates treatment options and leads to beneficial outcomes for patients, their carers and the healthcare system. The neuropsychological battery of the Uniform Data Set (UDSNB3.0) assesses cognition in ageing and dementia, by measuring scores across different cognitive domains such as attention, memory, processing speed, executive function and language. However, its neuroanatomical correlates have not been investigated using 7 Tesla MRI (7T MRI).

METHODS

We used 7T MRI to investigate the correlations between hippocampal subfield volumes and the UDSNB3.0 in 24 individuals with Amyloidβ-status AD and 18 age-matched controls, with respective age ranges of 60 (42-76) and 62 (52-79) years. AD participants with a Medial Temporal Atrophy scale of higher than 2 on 3T MRI were excluded from the study.

RESULTS

A significant difference in the entire hippocampal volume was observed in the AD group compared to healthy controls (HC), primarily influenced by CA1, the largest hippocampal subfield. Notably, no significant difference in whole brain volume between the groups implied that hippocampal volume loss was not merely reflective of overall brain atrophy. UDSNB3.0 cognitive scores showed significant differences between AD and HC, particularly in Memory, Language, and Visuospatial domains. The volume of the Dentate Gyrus (DG) showed a significant association with the Memory and Executive domain scores in AD patients as assessed by the UDSNB3.0.. The data also suggested a non-significant trend for CA1 volume associated with UDSNB3.0 Memory, Executive, and Language domain scores in AD. In a reassessment focusing on hippocampal subfields and MoCA memory subdomains in AD, associations were observed between the DG and Cued, Uncued, and Recognition Memory subscores, whereas CA1 and Tail showed associations only with Cued memory.

DISCUSSION

This study reveals differences in the hippocampal volumes measured using 7T MRI, between individuals with early symptomatic AD compared with healthy controls. This highlights the potential of 7T MRI as a valuable tool for early AD diagnosis and the real-time monitoring of AD progression and treatment efficacy.

CLINICALTRIALS

GOV: ID NCT04992975 (Clinicaltrial.gov 2023).

Developing automated methods for disease subtyping in UK Biobank: an exemplar study on stroke

BACKGROUND

Better phenotyping of routinely collected coded data would be useful for research and health improvement. For example, the precision of coded data for hemorrhagic stroke (intracerebral hemorrhage [ICH] and subarachnoid hemorrhage [SAH]) may be as poor as < 50%. This work aimed to investigate the feasibility and added value of automated methods applied to clinical radiology reports to improve stroke subtyping.

METHODS

From a sub-population of 17,249 Scottish UK Biobank participants, we ascertained those with an incident stroke code in hospital, death record or primary care administrative data by September 2015, and ≥ 1 clinical brain scan report. We used a combination of natural language processing and clinical knowledge inference on brain scan reports to assign a stroke subtype (ischemic vs ICH vs SAH) for each participant and assessed performance by precision and recall at entity and patient levels.

RESULTS

Of 225 participants with an incident stroke code, 207 had a relevant brain scan report and were included in this study. Entity level precision and recall ranged from 78 to 100%. Automated methods showed precision and recall at patient level that were very good for ICH (both 89%), good for SAH (both 82%), but, as expected, lower for ischemic stroke (73%, and 64%, respectively), suggesting coded data remains the preferred method for identifying the latter stroke subtype.

CONCLUSIONS

Our automated method applied to radiology reports provides a feasible, scalable and accurate solution to improve disease subtyping when used in conjunction with administrative coded health data. Future research should validate these findings in a different population setting.

Spontaneous hemorrhagic strokes during pregnancy: case report and review of the literature

Hemorrhagic stroke is responsible for significant morbidity and mortality. Postpartum and pregnancy are risk period. Only urgent care in intensive care units may improve prognosis. We report the case of 22 years old's Morrocan, who presented to our department with an intense headache headset followed a few hours later by consciousness disorder. Clinical examination at admission has objectified a woman obsessed with a GCS 13, normotensive, the labstix is negative. A brain scan was performed showing left temporal intra parenchymal hematoma with ventricular flooding and subfalcine herniation. An external ventricular shunt was made. The patient was extubated on day 2 of hospitalization, with progressive neurological improvement. Concerning obstetrical care, the pregnancy has evolved harmoniously without any growth retardation or other abnormalities, with full-term vaginal delivery of a healthy 3kg200 baby. although Hemorrhagic stroke during pregnancy is rare, the prognosis is reserved. An adequate care in intensive care unit is required.

The clinical features of 67 patients with clinically definite Steele-Richardson-Olszewski syndrome

The clinical features of 67 patients with probable Steele-Richardson-Olszewski syndrome have been analysed. Bradykinesia was present in 92.5% of cases at the time of initial assessment and the two commonest presenting complaints were walking difficulties and stiffness. Only 11 patients had a supranuclear gaze palsy when first seen. Forty-nine patients developed cognitive impairment in the course of their illness based on neuropsychological testing. In addition to the classical clinical findings occasional other findings included focal dystonia, tonic inhibition of levator palpebrae and blepharospasm, respiratory disturbances and impaired hearing. Only nine cases responded at all to levodopa therapy.