ABSTRACT NUMBER: ESOC2026A932 OPPORTUNISTIC BRAIN MRI–DERIVED PHARYNGEAL LENGTH OUTPERFORMS STOP-BANG IN SCREENING SEVERE OBSTRUCTIVE SLEEP APNEA AFTER ACUTE ISCHEMIC STROKE

Abstract Background and aims Obstructive sleep apnea (OSA) affects two-thirds of acute ischemic stroke (AIS) patients and predicts recurrent stroke and poor recovery. Current screening with STOP-BANG is limited by subjectivity and feasibility issues like aphasia. We evaluated whether opportunistic measurement of upper airway dimensions on routine brain MRI could serve as an objective screening strategy for severe OSA. Methods In this prospective single-center study (April–October 2024), 103 adults with AIS underwent standard-of-care brain MRI. We measured retropalatal and combined retropalatal–retroglossal pharyngeal length (CRR) on mid-sagittal T1-weighted sequences. OSA severity was confirmed via cardiorespiratory polygraphy. We compared the diagnostic performance (AUC, sensitivity, specificity) of MRI measurements against the STOP-BANG questionnaire for detecting severe OSA. Results Participants (mean age 59.6±11.2; 71.8% male) had mild-to-moderate stroke (median NIHSS 3 [IQR 2–4]) and mean BMI 24.1±3.1 kg/m2. CRR was significantly longer in severe OSA patients versus non-severe (66.6±8.9 mm vs. 62.5±8.1 mm; p=0.048). CRR showed superior discriminative accuracy (AUC=0.70, 95% CI 0.61–0.78) compared to STOP-BANG≥3 (AUC=0.57, 95% CI 0.48–0.65). A CRR cutoff of ≥62 mm achieved 91% sensitivity and 49% specificity, significantly outperforming STOP-BANG (90% sensitivity, 24% specificity). Conclusions Opportunistic CRR measurement on routine brain MRI provides a rapid, objective, and high-sensitivity approach for identifying patients at high risk for severe OSA risk in acute stroke. By leveraging existing neuroimaging without additional cost or workflow disruption, this strategy overcomes the limitations of questionnaire-based screening in the acute phase. Conflict of interest Tho Phung: nothing to disclose Hoai-Thi-Thu Nguyen: nothing to disclose Giap Vu: nothing to disclose Duy-Ton Mai: nothing to disclose Khanh Le: nothing to disclose