Ultra-short acting insulin can improve on F-18 FDG PET/CT image quality in patients with uncontrolled diabetic mellitus

Objectives It is well known that the image quality of 18F-FDG PET is poor to interpret in patients with uncontrolled diabetic mellitus (DM). We usually had to delay the schedule, when the patients showed high glucose level. This study was performed to evaluate the usefulness and effects of ultra-short acting insulin on 18F-FDG PET/CT imaging in patients with DM.

Methods One hundred and five patients (M/F=68/37) with DM were included. The ultra-short acting insulin (humalog) was intravenously injected when the patients showed high glucose level (over 191mg/dl). 18F-FDG was injected at 60 minutes after humalog injection and PET/CT images were acquired. Two experienced nuclear physicians evaluated quality of images, graded by consensus on a scale from 0 to 2: 0, good; 1, moderate; 2, poor. To assess the effects of humalog, the maximum SUV(SUVmax) of liver and femoral muscle were evaluated all of patients.

Results The group with humalog (n=52, blood glucose level: 243.7±46.2mg/dL) showed significantly higher glucose level than the other group without humalog (n=53, 177.1±5.2mg/dL). Nevertheless, the image quality of the group with humalog had no significant differences with the other group without humalog (Chi-square test, p=0.47). There were no significant differences of SUVmax in liver (p=0.26) and femoral muscle (p=0.56) between two groups.

Conclusions Ultra-short acting insulin in 18F-FDG PET/CT may be used to improve image quality in uncontrolled diabetic mellitus patients without significant differences of SUV