T 1 ρ Magnetic Resonance Fingerprinting in Patients With Chronic Pancreatitis

ABSTRACT Background Noninvasive detection of chronic pancreatitis (CP) is important for proper treatment and prevention of severe pain and pancreatic insufficiency. Purpose To evaluate if T 1 ρ MRF is significantly different in healthy volunteers and patients with CP. Study Type Prospective. Population Seventeen healthy volunteers (9 male, mean age: 38.0 ± 6.7 years) and 20 patients (12 male, mean age: 53.6 ± 6.4 years) who were clinically diagnosed with CP. Field Strength/Sequence 3 T, T 1 ρ MRF acquired during breath‐hold (BH‐MRF) and free breathing (FB‐MRF), conventional T 1 /T 2 mapping sequences. Assessment Mean T 1 /T 2 /T 1 ρ values in the whole pancreas were compared between diagnosed CP patients and controls. The Cambridge classification (CC) score was used to divide patients into mild–moderate (CC = 1–3) and severe (CC = 4) CP subgroups. T 1 , T 2 , and T 1 ρ relaxation maps were generated from both breath‐hold (BH) and free‐breathing (FB) MRF data. Statistical Tests Mixed effects models were calculated for healthy control versus CP, and between mild–moderate and severe CP. Receiver operator characteristic (ROC) curves were analyzed and areas under the curves (AUCs) were calculated. A p ‐value < 0.05 was considered significant and multiple comparison corrections were applied. Results BH‐MRF T 1 /T 2 /T 1 ρ values were significantly higher in the CP group (1327.3, 48.6, 49.1 ms) compared to healthy controls (821.6, 41.6, 39.5 ms) with AUCs of 0.994, 0.873, and 0.862, respectively. The MRF BH T 1 /T 2 /T 1 ρ values of mild–moderate CP ( N = 7) and severe CP ( N = 13) patients were also significantly higher compared to healthy controls. T 1 was significantly higher in severe CP compared to mild–moderate CP (1497 and 1012.1 ms, respectively) with AUC = 0.945. FB MRF T 1 relaxation times demonstrated good correlation with BH values (0.981), while T 2 and T 1 ρ had moderate correlations (0.507 and 0.697, respectively). Data Conclusions T 1 , T 2 , and T 1 ρ relaxation times have potential for noninvasively assessing CP. Evidence Level 2. Technical Efficacy Stage 2.