Determination of normative standardized uptake values for pancreatic 18F-FDOPA-PET compared to patients with post-gastric bypass hyperinsulinemic hypoglycemia.

Ginkel, B. van (2014) Determination of normative standardized uptake values for pancreatic 18F-FDOPA-PET compared to patients with post-gastric bypass hyperinsulinemic hypoglycemia. thesis, Medicine.

Text GinkelvanB.pdf Restricted to Registered users only Download (860kB)

Abstract

Background: Hyperinsulinemic hypoglycemia after Roux-en-Y gastric bypass (RYGB) has been increasingly reported. It is induced by beta-cell hyperplasia often referred to as nesidioblastosis. Positron emission tomography with 6-[18F]fluoro-3,4-dihydroxy-L-phenylalanine (18F-DOPA) has been successfully applied to image neuro-endocrine tumors. No data are available of the usefulness of this functional imaging technique including the role of carbidopa pretreatment to distinguish between post-RYBG patients with this new endocrine disorder and a control population,. Aim: To describe pancreas tracer uptake in controls and in patient with nesidioblastosis using 18F-FDOPA PET/CT imaging. To assess the diagnostic accuracy of 18F –FDOPA PET tracer uptake in discriminating between nesidioblastosis and physiological uptake. Patients and methods: All patients (n=371) who underwent an 18F-FDOPA-PET/CT scan according to EANM guidelines in our hospital between November 2009 and May 2012 were included in this study. The scans of these patients were retrospectively analyzed and all records in the local corresponding electronic hospital information system were reviewed. Standardized uptake value (SUV) for the head, body and tail regions of the pancreas and a summation uptake value of all these regions were calculated for controls and nesidioblastosis patients. Controls were divided in a carbidopa positive and negative control group for comparison with nesidioblastosis patients This research study was approved by the local medical ethics committee of our hospital. Results: Median (IQR) mean pancreatic uptake in the head, body and tail regions with carbidopa pretreatment in controls was 1.76 (1.57-1.99) for the head, 1.66 (1.49-1.83) for the body and 1.67 (1.51-1.87) for the tail. Without carbidopa pretreatment this was 2.02 (1.73-2.29); 2.18 (1.59-2.47) and 2.30 (1.72-2.48), respectively, (all P values < 0.05). In patients with nesidioblastosis (scanned without carbidopa pretreatment), this was 2.66 (2.41-3.00) for the pancreas head 2.86 (2.53-3.53) for the body and 2.77 (2.67-3.34) for the tail (all P values < 0.05). A summation uptake of the mean values of all regions of 7.30 had a sensitivity of 100% and a specificity of 89% discriminating between nesidioblastosis and carbidopa negative controls. Conclusion: In patients with nesidioblastosis, standardized uptake values for pancreatic head, body and tail regions were significantly higher than in controls without carbidopa pretreatment. In addition, carbidopa pretreatment significantly lowers pancreatic tracer uptake in controls. A summation SUV of all pancreatic regions discriminates between post RYGB nesidioblastosis and controls.

Item Type:	Thesis (Thesis)
Supervisor name:	Beek, Dr. A.P. van
Faculty:	Medical Sciences
Date Deposited:	25 Jun 2020 10:56
Last Modified:	25 Jun 2020 10:56
URI:	https://umcg.studenttheses.ub.rug.nl/id/eprint/1650

Actions (login required)

View Item