Single-subject classification of presymptomatic frontotemporal dementia mutation carriers using multimodal MRI

Background

Classification models based on magnetic resonance imaging (MRI) may aid early diagnosis of frontotemporal dementia (FTD) but have only been applied in established FTD cases. Detection of FTD patients in earlier disease stages, such as presymptomatic mutation carriers, may further advance early diagnosis and treatment. In this study, we aim to distinguish presymptomatic FTD mutation carriers from controls on an individual level using multimodal MRI-based classification.

Methods

Anatomical MRI, diffusion tensor imaging (DTI) and resting-state functional MRI data were collected in 55 presymptomatic FTD mutation carriers (8 microtubule-associated protein Tau, 35 progranulin, and 12 chromosome 9 open reading frame 72) and 48 familial controls. We calculated grey and white matter density features from anatomical MRI scans, diffusivity features from DTI, and functional connectivity features from resting-state functional MRI. These features were applied in a recently introduced multimodal behavioural variant FTD (bvFTD) classification model, and were subsequently used to train and test unimodal and multimodal carrier-control models. Classification performance was quantified using area under the receiver operator characteristic curves (AUC).

Results

The bvFTD model was not able to separate presymptomatic carriers from controls beyond chance level (AUC = 0.570, p = 0.11). In contrast, one unimodal and several multimodal carrier-control models performed significantly better than chance level. The unimodal model included the radial diffusivity feature and had an AUC of 0.646 (p = 0.021). The best multimodal model combined radial diffusivity and white matter density features (AUC = 0.680, p = 0.005).

Conclusions

FTD mutation carriers can be separated from controls with a modest AUC even before symptom-onset, using a newly created carrier-control classification model, while this was not possible using a recent bvFTD classification model. A multimodal MRI-based classification score may therefore be a useful biomarker to aid earlier FTD diagnosis. The exclusive selection of white matter features in the best performing model suggests that the earliest FTD-related pathological processes occur in white matter.

Clinical spectrum and risk factors associated with asymptomatic erosive esophagitis as determined by Los Angeles classification: A cross-sectional study

BACKGROUND

Gastro esophageal reflux disease (GERD) is a chronic and recurrent disease, and it varies in regions. However, to date, there are no reports available on clinical features and the risk factors for the asymptomatic reflux esophagitis in Nepalese adults.

METHODS

Data were gathered from 142 erosive patients who had undergone endoscopy at Bir Hospital, Kathmandu. Los Angeles classification was used to grade the severity of the disease. Patients were interviewed to find out the presence of various reflux symptoms.

RESULTS

Based on the Los Angeles classification, the severity of the disease assessed was; grade A 31.8% (31/142), grade B 39.4% (56/142), grade C 33.8% (48/142), and grade D 4.9% (7/142). One hundred and twenty six (88.7%) subjects had reflux symptoms. Prevalence of asymptomatic esophagitis was 16(11.3%). Age was independently linked to asymptomatic esophagitis (P<0.05), and the odd of being asymptomatic appeared lower in younger adults (P<0.05; OR: 0.118; CI: 0.014-.994).

CONCLUSION

A low prevalence of asymptomatic reflux esophagitis (RE) was seen. Most subjects experienced mild to moderate RE. Age remained an independent factor associated with reflux esophagitis, and the odds of being asymptomatic was lower in younger age.

International Work Group criteria for the diagnosis of Alzheimer disease

Alzheimer-type biomarker changes are identifiable in asymptomatic and mildly symptomatic predementia phases of Alzheimer disease (AD) and AD dementia. The International Work Group (IWG) guidelines for diagnosis identify a unified spectrum of 3 phases. The classic clinical feature that indicates AD is an episodic memory defect of the amnestic type. IWG criteria require biomarker support for the diagnoses of AD at any clinical stage. Pathophysiologic and topographic biomarkers are recognized. These criteria are proposed to allow highly specific diagnosis of AD and assist in identifying patients for clinical trials of AD-related treatments and other types of AD research.

Endodontic diagnostic terminology update

Determination of the etiology of the patient's chief complaint and a correct diagnosis are paramount prior to a recommendation of endodontic therapy. Reproduction of the patient's chief complaint is critical. If the chief complaint cannot be reproduced, consider consultation with or referral to an endodontist or orofacial pain specialist. The diagnostic terminology presented in this update provides for a more accurate description and communication of the health or pathological conditions of both pulpal and apical tissues. This information is summarized in Table I.