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Endoscopic Endonasal Trans-sphenoidal Approach: Minimally Invasive Surgery for Pituitary Adenomas
Published on: January 17, 2018
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Reduced Dynamic Brain Activity and Functional Connectivity in Nonfunctioning Pituitary Adenomas with Visual
Jing Tang1, Wencheng Shen2, Pingyi Zhu3
1From the Department of Radiology (J.T., M.L., B.H., F.L., Y.W.), Sichuan Provincial People's Hospital, University of Electronic Science and Technology of China, Chengdu, China.
AJNR. American Journal of Neuroradiology
|November 6, 2025
Summary
Nonfunctioning pituitary adenoma (NFPA) patients with visual impairment show reduced brain activity and connectivity in visual areas. These changes correlate with tumor size and visual field defects, revealing new insights into NFPA's neuropathology.
Area of Science:
- Neuroimaging
- Neuroscience
- Medical Imaging
Background:
- Nonfunctioning pituitary adenoma (NFPA) can cause visual disturbance via chiasmal compression.
- Brain dysfunction is known in visually impaired patients, but dynamic brain activity features are underexplored.
Purpose of the Study:
- To explore changes in temporal variability of spontaneous brain activity and functional connectivity in visually impaired NFPA patients.
- To investigate the relationship between altered brain dynamics and chiasmal compression severity and visual field defects.
Main Methods:
- Resting-state functional MRI (fMRI) was used in 36 NFPA patients and 36 controls.
- Dynamic amplitude of low-frequency fluctuation (dALFF) and dynamic functional connectivity (dFC) analyses assessed temporal variability.
- Correlations with chiasmal volume, compression duration, and visual field defect severity were evaluated.
Main Results:
- NFPA patients showed significantly reduced dALFF in the lingual gyrus (LING) and calcarine fissure (CAL) compared to controls.
- A significant reduction in dFC was observed between the right LING and bilateral precuneus in patients.
- Altered dALFF correlated positively with chiasmal volume and mean deviation (visual field defect severity).
Conclusions:
- Visually impaired NFPA patients exhibit decreased temporal variability in brain activity and connectivity within visual-related regions.
- These findings offer novel insights into the neuropathologic mechanisms underlying visual disturbance in NFPA.
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