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).

Side Effects of Permanent Radioactive Iodine-125 Implants Brachytherapy for Prostate Cancer in Nigeria

BACKGROUND

Radioactive seeds implant is a novel option in the developed world for the treatment of organ-confined prostate cancer; however, it is a rare procedure in developing countries, especially in sub-Saharan African countries like Nigeria. The first prostate brachytherapy in Nigeria was performed in 2019 at La'Newton Oncology Clinic using low-dose radioactive iodine-125. The side effects on patients that were treated in three years of its existence in Nigeria are documented in this study.

OBJECTIVES

This study aimed to narrate the side effects and complications of the procedure in its three years of existence in Nigeria.

METHODS

This was a retrospective study of the 32 eligible patients treated at the only private clinic that offers permanent radioactive iodine-125 prostate seeds implant in Nigeria. The patients were followed-up for 24 months. The biodata, urinary symptoms and erectile function were analyzed using the medical records, a detailed expanded prostate cancer index composite questionnaire, and a modified Radiation Therapy Oncology Group Grading System.

RESULT

It was noticed that the burning sensation at the perineum, which was self-limiting within 72 hours, was a major complaint among all the subjects. All the patients experienced haematuria; 74% of the subjects noted that the haematuria resolved within 12 hours post-implant, while it resolved within 24 hours for the remaining 26%. Acute urinary retention occurred in one subject. The EPIC scoring system showed that only one subject lost the ability to have a firm erection adequate for sexual intercourse. There was no gastrointestinal toxicity recorded among the participants.

CONCLUSION

The side effects observed among the subjects were negligible compared to conventional surgery, so this procedure should be considered in all cases of organ-confined prostate cancer, especially as it is also cost-effective.