Magnetic resonance imaging: a reliable method for measuring pancreatic volume in Type 1 diabetes

Aim To validate magnetic resonance imaging (MRI) for monitoring pancreatic atrophy in Type 1 diabetes. Methods Twelve male patients with Type 1 diabetes of duration >= 10 years (median age 28, range 19-32 years) and 12 healthy controls (median age 30, range 22-36 years) were invited for two abdominal MRI scans, 14 days apart. Four sequences were used: standard T1-weighted; standard T2-weighted; volumetric interpolated breath-hold examination (VIBE); and T1-weighted breath hold with fat suppression (T1BHFS). The pancreas was identified on coded images by one observer and volumes estimated by interpolation. Results Eleven patients and all controls were scanned twice. Visualization of the pancreas was best with VIBE and T1BHFS, allowing volume estimation from 47 and 46 scans, respectively. The pancreatic volume of patients estimated from these sequences were half those of controls (52.4 ml, +/- 17.1 ml, mean +/- SD) vs. (101 ml, +/- 19.5 ml, P < 0.001) and estimates showed little bias between visits; mean difference 1.1 ml (95% CI; -3.1 to 5.3 ml, P = 0.61) using VIBE and -2.6 ml (-5.8 to 0.6 ml, P = 0.03) using T1BHFS. Both sequences gave similar precision; the standard deviation of the differences in volume estimates between visits was 9.7 ml for VIBE and 7.3 ml for T1BHFS, although mean volumes estimated from T1BHFS were 4.9 ml lower (-8.2 to -1.7 ml, P = 0.005). Conclusions Pancreatic volume can be measured reliably using MRI and shows a 48% reduction in long-standing Type 1 diabetes as compared with age-matched normal subjects. MRI should prove useful in determining the natural history of pancreatic atrophy in diabetes.