MRI Prediction of Islet Yield for Autologous Transplantation After Total Pancreatectomy for Chronic Pancreatitis

The relationship between magnetic resonance imaging (MRI), histopathology, and islet yield was examined for chronic pancreatitis patients undergoing total pancreatectomy and autologous islet cell transplant (TP-AIT) to determine if the yield can be predicted by pre-operative MRI.

MRI sequences and histopathology were scored and compared for patients from whom ≤2,500 islet equivalents/kg were obtained with those from whom >2,500 islet equivalents/kg were obtained.

Twenty patients, 14 female, mean age 40.20 ± 12.5 years, (range 19–63) underwent MRI before TP-AIT; mean 3,724 ± 891 islet equivalents/kg body weight, median 2,970, (range 76–17,770) were procured. There was no correlation between islet cell numbers and pancreas weight, HgbA1c, or c-peptide. The most common MRI sequence abnormality was the delayed interstitial phase, 14/18 (78 %). The other common MRI sequence abnormalities were, precontrast T1W 3D GRE sequence, 13/19 (68 %), and the arterial perfusion phase, 11/18 (61 %). The pancreatic duct was dilated in 10/20 (50 %). Parenchymal atrophy was noted in 10/20 (50 %). Median scores for individual MRI sequences were greater in patients with an islet cell yield of ≤2,500 islet equivalents/kg; for the delayed interstitial phase the difference was significant (median 2.5, range 1–3 versus median 0.5, range 0–3, P = 0.034). Histologically the most common feature was fibrosis, (17/17, 100 %); the score for fibrosis was greater for patients with an islet cell yield of ≤2,500 islet equivalents/kg (median 6.0, range 5–7 versus median 4.0, range 3–7, P = 0.024).

A diminished islet yield may be predicted on the basis of the delayed interstitial phase MRI sequence.