Clinical Feasibility and Tolerance of Oxygen-Enhanced MRI for Assessing Tumor Hypoxia in Nasopharyngeal Carcinoma

Motivation: Oxygen-enhanced magnetic resonance imaging (OE-MRI) is an attractive technique that monitor tumour oxygenation. Goal(s): To investigate if dynamic T1-mapping with OE-MRI could be performed to detect hypoxia in NPC. And, to assess differences of OE-MRI-derived parameters between the NPC and the opposite side lateral pterygoid muscle (termed YWJ). Approach: Thirteen NPC patients were scanned the OE-MRI. Baseline tissue longitudinal relaxation time (T1) and 1/T1 (termed R1) was measured alongside the change in R1 (termed ΔR1) between air and oxygen gas breathing phases. Results: The ΔR1 of oxygen gas breathing phases in both NPC and YWJ were significantly higher than air breathing. Impact: Dynamic T1-mapping with OE-MRI to indicate hypoxia of NPC and the derived parameter ΔR1 may be a repeatable hypoxia biomarker. OE-MRI is promising to guide clinical work of biology guided adaptive radiotherapy.