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Study design Retrospective study. Purpose This study aims to semiquantitatively evaluate the standardized uptake value (SUV) of 99mTc-methylene diphosphonate (MDP) radionuclide tracer in the normal vertebrae of breast cancer patients using an integrated single-photon emission computed tomography (SPECT)/computed tomography (CT) scanner. Overview of literature Molecular imaging techniques using gamma cameras and stand-alone SPECT have traditionally been utilized to evaluate metastatic bone diseases. However, these methods lack quantitative analysis capabilities, impeding accurate uptake characterization. Methods A total of 30 randomly selected female breast cancer patients were enrolled in this study. The SUV mean (SUVmean) and SUV maximum (SUVmax) values for 286 normal vertebrae at the thoracic and lumbar levels were calculated based on the patients' body weight (BW), body surface area (BSA), and lean body mass (LBM). Additionally, 106 degenerative joint disease (DJD) lesions of the spine were also characterized, and both their BW SUVmean and SUVmax values were obtained. A receiver operating characteristic (ROC) curve analysis was then performed to determine the cutoff value of SUV for differentiating DJD from normal vertebrae. Results The mean±standard deviations for the SUVmean and SUVmax in the normal vertebrae displayed a relatively wide variability: 3.92±0.27 and 6.51±0.72 for BW, 1.05±0.07 and 1.75±0.17 for BSA, and 2.70±0.19 and 4.50±0.44 for LBM, respectively. Generally, the SUVmean had a lower coefficient of variation than the SUVmax. For DJD, the mean±standard deviation for the BW SUVmean and SUVmax was 5.26±3.24 and 7.50±4.34, respectively. Based on the ROC curve, no optimal cutoff value was found to differentiate DJD from normal vertebrae. Conclusions In this study, the SUV of 99mTc-MDP was successfully determined using SPECT/CT. This research provides an approach that could potentially aid in the clinical quantification of radionuclide uptake in normal vertebrae for the management of breast cancer patients.

Background It is unclear if the 99mTc-sodium phytate (99mTc-SP) is as reliable as the gold-standard 99mTc-sulfur colloid (99mTc-SC) for gastric emptying scintigraphy (GES). This study is aimed to compare the emptying rates of both radiotracers in a prospective, randomized cross-over trial and to determine the normative data of a healthy multi-ethnic Asian population. Methods Out of the 44 healthy individuals screened, 31 (14 females; mean age: 28.4 ± 7.0 years) were enrolled and underwent GES using the standardized egg-white meal. All participants were randomly assigned to either 99mTc-SP or 99mTc-SC on the first GES session before crossed over to the other formulation after 2 weeks. Results Both kits achieved the radiochemical purities of > 95%. The median rate (95th upper normative limit) of gastric emptying, reported as total gastric meal retention between 99mTc-SP and 99mTc-SC, was found to be comparable at all measured time points: 0.5 h [85.0% (96.6%) vs. 82.0% (94.0%)], 1 h [70.0% (86.4%) vs. 65.0% (86.6%)], 2 h [31.0% (55.8%) vs. 25.0% (64.4%)], 3 h [7.0% (26.3%) vs. 5.0% (29.9%)], and 4 h [3.0% (10.3%) vs. 2.0% (9.9%)]; P > 0.05. In addition, both radiotracers correlated well (Kendall’s Tau (τ) coefficient = 0.498, P Conclusions 99mTc-SP is a valid radiotracer alternative to 99mTc-SC for routine GES examination. The normative values for both radiotracers have also been determined for the healthy multi-ethnic Asian population. Trial registration This trial was registered retrospectively in the Thai Clinical Trials Registry on May 23rd, 2020 (Identifier: TCTR20200526004; http://www.clinicaltrials.in.th/index.php?tp=regtrials&menu=trialsearch&smenu=fulltext&task=search&task2=view1&id=6296).

Planar scintigraphy with 99mTc-pertechnetate or Meckel scan is the gold standard in the diagnosis of a bleeding Meckel’s diverticulum (MD) for pediatrics. However, several setbacks may occur during the interpretation of a scintigram, especially in cases of an atypical MD presentation. In this report, we highlight the importance of functional and anatomical image co-registration using a hybrid SPECT/CT scanner to precisely localize a MD lesion. An 18-month-old boy presented with severe hematochezia over 4 days with declining hemoglobin levels. He underwent a conventional 60-min dynamic planar imaging of the Meckel scan. Upon review of the Meckel scan, a suspicious increase in the 99mTc-pertechnetate uptake was observed at the right upper quadrant of the abdomen. Due to its atypical location at the right kidney, we could not differentiate between a physiological uptake of the right kidney or an ectopic gastric mucosa. The patient was imaged again using single-photon emission computed tomography (SPECT) and low-dose CT protocol with a hybrid SPECT/CT scanner, and the co-registration of both SPECT and CT images was able to confirm the MD, which was located anterior to the right kidney at the right hepatic flexure region. An exploratory laparotomy was then ensued to remove the bleeding MD. The patient was discharged after 3 days with no complications. In summary, this case illustrates that hybrid imaging modality and co-registration allow for a more definitive diagnosis, as well as a more precise localization of MD.

Proper dosimetry settings are crucial in radiotherapy to ensure accurate radiation dose delivery. This work evaluated scanning parameters as affecting factors in reading the dose-response of EBT2 and EBT3 radiochromic films (RCFs) irradiated with clinical photon and electron beams. The RCFs were digitised using Epson® Expression® 10000XL flatbed scanner and image analyses of net optical density (netOD) were conducted using five scanning parameters i.e. film type, resolution, image bit depth, colour to grayscale transformation and image inversion. The results showed that increasing spatial resolution and deepening colour depth did not improve film sensitivity, while grayscale scanning caused sensitivity reduction below than that detected in the Red-channel. It is also evident that invert and colour negative film type selection negated netOD values, hence unsuitable for scanning RCFs. In conclusion, choosing appropriate scanning parameters are important to maintain preciseness and reproducibility in films dosimetry.