Opportunistic screening for osteopathy with routine abdominal computed tomography scan in chronic pancreatitis

Lumbar vertebral bone attenuation, measured in Hounsfield units (HU) can indirectly indicate the bone mineral density (BMD). The aim of this study is to determine the optimal HU threshold on abdominal computed tomography (CT) scans to detect osteopathy in patients with chronic pancreatitis (CP).

This cross-sectional study included patients with CP who underwent CT scans to measure HU at L1 to L4 vertebrae. The mean lumbar vertebral attenuation of female renal transplant donors, aged 20-30 years was utilized to calculate the T-score^HU of all patients at each vertebral level. Receiver operator characteristic analysis was used to determine the HU and T-score^HU for diagnosis of osteopathy in patients with CP. Dual-energy X-ray absorptiometry value was used to categorize osteopenia and osteoporosis.

A total of 175 patients (mean age, 34.5 ± 10.9 years; 72 % males) and 33 female renal transplant donors (mean age, 28 ± 2.4 years) were included. A threshold HU value 212 or T score^HU of -1.80 at L1 vertebra was found to have a 78 % sensitivity and 70 % specificity for differentiating between osteoporosis and non-osteoporosis (osteopenia and normal BMD). Similarly, a threshold HU value of 254 or a T-score^HU of -0.46 at L1 vertebra had 78 % sensitivity and 71 % specificity for distinguishing between normal and low BMD (osteoporosis and osteopenia).

Abdominal CT images, which are routinely performed in chronic pancreatitis, can be used for opportunistic screening of osteoporosis and osteopenia without additional cost or radiation exposure.