Frequency-specific alterations of the resting-state BOLD signals in nocturnal enuresis: an fMRI Study

Xiangyu Zheng,Jun Ma,Yating Lv,Xize Jia,Jiawei Sun,Xiaoxia Du,Mengxing Wang

doi:10.1038/s41598-021-90546-3

Abstract

Resting state functional magnetic resonance imaging studies of nocturnal enuresis have focused primarily on regional metrics in the blood oxygen level dependent (BOLD) signal ranging from 0.01 to 0.08 Hz. However, it remains unclear how local metrics show in sub-frequency band. 129 children with nocturnal enuresis (NE) and 37 healthy controls were included in this study. The patients were diagnosed by the pediatricians in Shanghai Children’s Medical Center affiliated to Shanghai Jiao Tong University School of Medicine, according to the criteria from International Children's Continence Society (ICCS). Questionnaires were used to evaluate the symptoms of enuresis and completed by the participants. In this study, fALFF, ReHo and PerAF were calculated within five different frequency bands: typical band (0.01–0.08 Hz), slow-5 (0.01–0.027 Hz), slow-4 (0.027–0.073 Hz), slow-3 (0.073–0.198 Hz), and slow-2 (0.198–0.25 Hz). In the typical band, ReHo increased in the left insula and the right thalamus, while fALFF decreased in the right insula in children with NE. Besides, PerAF was increased in the right middle temporal gyrus in these children. The results regarding ReHo, fALFF and PerAF in the typical band was similar to those in slow-5 band, respectively. A correlation was found between the PerAF value of the right middle temporal gyrus and scores of the urinary intention-related wakefulness. Results in other bands were either negative or in white matter. NE children might have abnormal intrinsic neural oscillations mainly on slow-5 bands.

Highlights

Nocturnal enuresis (NE) is defined as repeatedly urinating in clothes or bed that occurs only during sleep in an individual who has reached a developmental age when urinary continence is ordinarily expected at 5 years old[1,2], with a prevalence of around 5% in children between 5 and 12 years old[3]
Amplitudes of low-frequency fluctuations (ALFF) and Regional homogeneity (ReHo) are two metrics widely used for uncovering local spontaneous neural activity in the brain and have been used in thousands
The results showed that in the typical band, ReHo increased in the left insula and the right thalamus in nocturnal enuresis (NE)

Summary

Introduction

Nocturnal enuresis (NE) is defined as repeatedly urinating in clothes or bed that occurs only during sleep in an individual who has reached a developmental age when urinary continence is ordinarily expected at 5 years old[1,2], with a prevalence of around 5% in children between 5 and 12 years old[3]. A variety of metrics has been proposed in the field of rs-fMRI that allow us to understand the spontaneous neural activity of the subject’s brain from various perspectives. Amplitudes of low-frequency fluctuations (ALFF) and Regional homogeneity (ReHo) are two metrics widely used for uncovering local spontaneous neural activity in the brain and have been used in thousands shsmu.edu.cn. ReHo is used to analyze spontaneous synchronization of local activity in the brain[13], whereas ALFF is used to analyze the amplitude of single voxel low frequency oscillations (amplitude)[14]. An improved ALFF algorithm named fractional amplitude of low-frequency fluctuation (fALFF) was proposed and able to be used to suppress noise and to provide a better one-sample t-test patten than ALFF15. Only a few articles focused on local spontaneous activity in NE c hildren[6,26,27], suggesting abnormalities in left inferior parietal lobule, left inferior frontal gyrus and left medial orbital superior frontal gyrus in the 0.01–0.08 Hz range in NE children compared to healthy controls (HCs)

Methods

Results

Conclusion