Resting-state functional magnetic resonance imaging findings in patients with acoustic neuroma and tinnitus

Objective To investigate the neural network mechanism of tinnitus in patients with acoustic neuroma by observing the imaging findings of resting-state functional magnetic resonance imaging (rs-fMRI). Methods A total of 18 patients with acoustic neuroma who were hospitalized in the Department of Otolaryngology, Head and Neck Surgery, the Second Affiliated Hospital of Guangxi Medical University from November 2022 to December 2023 for concurrent surgical treatment were divided into a tinnitus group (group A) and a non-tinnitus group (group B) based on the presence or absence of tinnitus. Additionally, 18 volunteers without acoustic neuroma and tinnitus were selected as the control group (group C). All patients underwent routine cranial MRI and fMRI scans to compare fractional amplitude of low frequency fluctuations (fALFF) and degree centrality (DC) values. Results The different brain regions of the fALFF values in the three groups were mainly located in the right fusiform gyrus, right middle temporal gyrus, right orbital inferior frontal gyrus, right insula and left medial superior frontal gyrus. Compared with group C, fALFF values in right middle temporal gyrus in group A were increased, fALFF values in right fusiform gyrus and right middle temporal gyrus in group B were increased, and fALFF values in right orbital inferior frontal gyrus, right insula, left medial superior frontal gyrus and middle frontal gyrus were decreased in group B (all P < 0.05). Compared with group B, fALFF values in right orbital inferior frontal gyrus, right insula, left medial superior frontal gyrus and middle frontal gyrus in group A were increased, while fALFF values in right fusiform gyrus and right middle temporal gyrus were decreased in group A (all P < 0.05). The different brain regions of the DC values in the three groups were mainly located in the right superior parietal gyrus and right anterior cuneiform lobe. Compared with group C, the DC values in the right superior parietal gyrus and right anterior cuneiform lobe in group A were lower (all P < 0.05). Compared with group B, the DC values in the right superior parietal gyrus and right anterior cuneiform lobe in group A were decreased (both P < 0.05). Conclusion This study reveals the changes in the brain regions associated with tinnitus in acoustic neuroma involving multiple networks of the central nervous system, including the auditory network, visual network, default mode network and dorsal attention network. These changes may be the neural network mechanism for the occurrence and development of tinnitus.