IMAGING PREDICTORS OF PANCREATIC HEALTH AND ISLET YIELD IN PEDIATRIC TOTAL PANCREATECTOMY WITH ISLET AUTOTRANSPLANTATION.

Introduction: Total pancreatectomy and islet auto-transplantation (TPIAT) can alleviate symptoms in chronic pancreatitis (CP). We aimed to identify pre-TPIAT imaging markers predicting explanted pancreas health and islet yield.

Methods: We retrospectively analyzed 104 pediatric TPIAT patients, excluding those with pre-surgical diabetes or pancreatic surgeries. Pancreas parenchymal volume was manually segmented and T1 signal intensity ratio pancreas to spleen (T1 SIRp/s) was calculated. An islet biologist assessed fat infiltration, fibrosis, and islet yield. Logarithmic transformation and regression analyses were used for variance stabilization and predictive modeling.

Results: 94 patients (60% female, median age 12.5 years) were included. Univariate analyses revealed that an increase in pancreas volume was associated with less fibrosis (OR=0.88 per 5 mL, 95% CI: 0.77-0.99, p<0.05), higher pellet volume, total islet equivalent (TIE) and total islet count (TIC). For advanced fibrosis, an increase in T1 SIRp/s was linked to decreased odds (OR=0.74 per 0.1 unit, 95% CI: 0.59-0.92, p<0.05), whereas a higher Cambridge score was associated with increased odds (OR=1.34 per 1 unit of Cambridge, 95% CI: 1.01-1.77, p<0.05). A model incorporating segmented pancreas volume and T1 SIRp/s predicted advanced fibrosis with an AUC of 0.75 (95%CI: 0.64-0.87). Additionally, models that included larger pancreas volume and the absence of acute pancreatitis predicted TIC and TIE.

Conclusion: In children with CP, non-invasive cross-sectional imaging focused on the parenchyma can guide the management, as a smaller parenchymal bulk and lower T1 SIRp/s predict advanced fibrosis, while larger pancreas volume and T1 SIRp/s predict larger pellet volumes.