polysomnography
Pronunciation: pol-ee-som-NOG-rah-fee
A comprehensive sleep study that simultaneously records multiple physiological parameters during sleep.
Full Definition
Polysomnography (PSG) is the gold standard diagnostic test for sleep disorders, involving continuous monitoring of brain waves (EEG), eye movements (EOG), muscle activity (EMG), heart rhythm (ECG), respiratory effort, airflow, and oxygen saturation throughout a complete sleep cycle. The study is typically conducted in a specialized sleep laboratory over an entire night, allowing for detailed analysis of sleep architecture, identification of sleep-disordered breathing, movement disorders, and other sleep-related abnormalities. Polysomnography data is scored according to standardized criteria to determine sleep stages, arousal events, and respiratory disturbances. The results help diagnose conditions such as sleep apnea, restless leg syndrome, and parasomnia disorders.
Usage
Usage note: Often abbreviated as PSG in clinical contexts, but spell out fully in patient education materials.
In Context
- "The polysomnography revealed severe obstructive sleep apnea with an apnea-hypopnea index of 45 events per hour." — Sleep medicine report
- "Patient authorization is required for the overnight polysomnography at the accredited sleep center." — Pre-procedure documentation