Quantitative measurement of standardized uptake value of lumbar vertebra by 99Tcm-MDP bone imaging with SPECT/CT

Abstract

Objective To explore the quantitative determination of standardized uptake value (SUV) of lumbar vertebra by 99Tcm-methylene diphosphonate (MDP) bone imaging with SPECT/CT. Methods A total of 90 patients (16 males, 74 females, age: (60.0±11.2) years) who underwent 99Tcm-MDP bone imaging and local lumbar SPECT/CT imaging from May 2017 to November 2017 were retrospectively analyzed. CT attenuation correction, scatter correction and 3-dimensional ordered subset expectation maximization (3D-OSEM) reconstruction were used. The radioactive counts of lumbar vertebra L1-L4 in patients with high MDP-uptake (including degenerative changes and bone metastases) and patients with non-high MDP-uptake (including osteoporosis and non-osteoporosis) were measured. Basing on that, the radioactivity of unit volume in lumbar and lesion was calculated and converted to SUV. The difference of SUV for lumbar and lesions from different types of patients was analyzed, and the correlation between lumbar SUV and varies of parameters were also analyzed. Data were analyzed by two-sample t test and Pearson correlation analysis. Results The mean SUV (SUVmean) and maximum SUV (SUVmax) of L1-L4 in 54 patients with non-high MDP-uptake were 4.64±1.03 and 7.09±1.61 respectively. They were positively correlated with bone mineral content, CT value and body weight (r values: 0.433-0.700, all P<0.05), and negatively correlated with age (r values: -0.514 and -0.456, both P<0.001). The SUVmean and SUVmax of patients with osteoporosis were 3.81±0.76 and 5.86±1.34 respectively, which were significantly lower than those of non-osteoporosis (5.13±0.84 and 7.82±1.30; t values: -5.892 and -5.240, both P<0.001). The SUVmean and SUVmax of 37 metastases were 16.40±6.07 and 24.25±11.35 respectively in 16 patients, which were significantly higher than those in patients with degenerative changes (20 patients with 27 lesions; 9.30±3.16 and 13.48±5.21; t values: 6.074 and 5.083, both P<0.001). Conclusion Based on the specific reconstruction algorithm and correction method, the SUV of lumbar vertebra on 99Tcm-MDP SPECT/CT bone imaging can be obtained, and the bone mineral metabolism can be reflected. Key words: Lumbar vertebrae; Radionuclide imaging; Technetium Tc 99m medronate; Tomography, emission-computed, single-photon; Tomography, X-ray computed