Journal of nuclear medicine technology最新文献

Calcific diskitis (CD) is a rare condition characterized by inflammation and calcification of an intervertebral disk, typically causing localized back pain. We present the case of a 65-y-old woman with a history of breast cancer and persistent back pain. SPECT/CT identified focal uptake at the T10-T11 vertebrae, localized to the intervertebral disk. Retrospective review of MR images from 2016 demonstrated a hypointense signal within the same disk on both T1- and T2-weighted images, consistent with disk calcification. This case highlights the utility of SPECT/CT in identifying CD and distinguishing it from other pathologies, including metastatic or degenerative spinal disease. CD should be considered in the differential diagnoses of backache.

Medical imaging is often used to determine the staging of the cancer and if it is localized or if it has spread. Metastatic prostate cancer is the concern and the lower survival rate, if not detected. Nuclear medicine has played a pivotal role in prostate metastasis detection and treatment for many decades. The emergence of prostate-specific membrane antigen (PSMA)-targeted PET radiopharmaceuticals has significantly advanced the imaging of prostate cancer. Among these, ¹⁸F-flotufolastat, commercially known as Posluma, represents a pivotal development in the detection and management of PSMA-positive lesions. Its favorable pharmacokinetics-including low urinary excretion and minimal bladder activity-enhance lesion detectability in the pelvic region, a common challenge in prostate imaging. Clinical trials such as LIGHTHOUSE and SPOTLIGHT demonstrated ¹⁸F-flotufolastat's high specificity, diagnostic accuracy, and safety profile across diverse patient populations. With a cyclotron-produced ¹⁸F isotope and a 110-min half-life, ¹⁸F-flotufolastat offers logistical advantages for imaging centers and flexibility in scan timing. As a PSMA-based agent, ¹⁸F-flotufolastat enables precise visualization of prostate cancer cells and metastatic sites, positioning it as a valuable tool in the evolving landscape of nuclear medicine and prostate cancer care.

The increased use of antiresorptive and antiangiogenic agents in patients with osteoporosis and cancer is closely linked to decreases in quality of life attributable to medication-related osteonecrosis of the jaw (MRONJ), emphasizing the need for accurate diagnosis. Recent advances in quantitative SPECT/CT (Q-SPECT/CT) using bone scintigraphy have enhanced its utility for the early detection and staging of MRONJ. However, the lack of harmonization criteria for SUVs across various scanners hampers multicenter studies. Methods: To address this issue, we conducted a multicenter phantom study to identify harmonization criteria for Q-SPECT/CT in MRONJ and evaluate a software-based harmonization approach. A custom-made brain tumor phantom with 6 hot spheres was filled with a ^99mTc-hydroxymethylene diphosphonate solution (17.5 kBq/mL in the background and 70 kBq/mL in the hot spheres, yielding a hot sphere-to-background ratio of 4). SPECT/CT was performed at 7 institutions using 8 scanners in accordance with clinical protocols. A cylindric phantom was used to calculate the becquerel calibration factor, and a tool for analyzing region of interest and volume of interest was used for SUV conversion, analysis, and harmonization. The harmonization criterion was the median SUV_max ± 30% across scanners. If the SUV_max exceeded this range, then a 3-dimensional gaussian filter was applied. Results: The SUV_mean in the background region remained within 0.95-1.05 (relative to the theoretic value of 1.00) both before and after harmonization, with minimal interscanner differences. Conversely, for the hot spheres, the maximum coefficients of variation for SUV_max, SUV_peak, and SUV_mean improved from 122%, 68%, and 71%, respectively, before harmonization to 48%, 35%, and 37%, respectively, after harmonization. Conclusion: We identified a harmonization criterion for Q-SPECT/CT in MRONJ and demonstrated that our software-based approach effectively reduces interscanner variability without compromising clinical image quality or requiring additional image reconstruction, supporting its utility in multicenter clinical studies.

Cardiovascular diagnostic imaging plays a crucial role in modern health care, supporting accurate diagnosis, risk stratification, and the management of cardiovascular diseases. However, ensuring that imaging is used appropriately has become a key focus in optimizing patient outcomes and resource use. This article examines the historical evolution of cardiovascular imaging, with a primary focus on nuclear cardiology, and discusses current challenges related to adhering to appropriate use criteria. It also explores the future potential of advanced technologies, including artificial intelligence and clinical decision-support systems. By addressing operational and clinical challenges and proposing strategies for collaboration and innovation, the health care community can bridge past lessons with future advancements to improve the appropriate use of cardiovascular diagnostic imaging.

Extraosseous Ewing sarcoma (EES) is a rare malignant tumor originating from soft tissue, comprising approximately 20% of all Ewing sarcoma cases. EES commonly involves the trunk or extremities, with pancreatic involvement being extremely uncommon. Because of its rarity, EES of the pancreas may be misdiagnosed initially and requires a multimodality approach. We present the case of a 25-y-old woman who was initially treated for acute pancreatitis. However, her symptoms persisted, and a [¹⁸F]FDG PET/CT was conducted for evaluation, the results of which suggested malignancy, which was later confirmed on biopsy as EES of the pancreas.

Primary aldosteronism (PA), which accounts for up to 14% of all hypertension cases and 25% of treatment-resistant hypertension cases, may be caused by unilateral or bilateral adrenal gland pathology. The identification of patients who are most likely to benefit from targeted intervention (i.e., adrenalectomy or nodule ablation) remains a challenge. Adrenal vein sampling is an invasive procedure with restricted availability, and recent studies have found that its accuracy in predicting surgical cure may be lower than previously thought. Molecular imaging with [¹¹C]metomidate ([¹¹C]MTO) PET is a noninvasive alternative, but the short half-life of ¹¹C prevents its widespread use. A novel fluorinated radiotracer, para-chloro-2-[¹⁸F]fluoroethyletomidate ([¹⁸F]CETO), has the potential to address this limitation because of its longer half-life. Initial reports suggest that [¹⁸F]CETO and [¹¹C]MTO have very similar visual (qualitative) appearances in patients with adrenal gland tumors. Methods: Using individual voxel measurements, we compared [¹⁸F]CETO and [¹¹C]MTO uptake in the adrenal glands of 31 patients with PA who were recruited to the extension phase of the MATCH clinical trial. Results: Qualitative comparisons of [¹⁸F]CETO and [¹¹C]MTO images showed comparable adrenal gland uptake, although [¹¹C]MTO demonstrated greater liver uptake, which obscured the right adrenal gland in some patients. Voxelwise comparisons yielded high correlation coefficients for both the left (r = 0.89) and right (r = 0.87) adrenal glands, which were statistically significant (P < 0.001). Bland-Altman analyses revealed mean SUV differences of 0.71 (CI, -6.09 to 7.51) for the left adrenal gland and 2.55 (CI, -5.91 to 11.00) for the right adrenal gland, indicating no significant bias between radiotracers. Conclusion: [¹⁸F]CETO and [¹¹C]MTO show remarkable similarity when used for molecular imaging in patients with PA. Notably, the right adrenal gland is more readily visualized with [¹⁸F]CETO, attributed to lower hepatic uptake. These findings, coupled with the longer half-life of ¹⁸F, should enable wider access to molecular imaging of the adrenal glands.

A 64-y-old woman presented to our hospital with general weakness, difficulty walking, and a history of kidney stones. Laboratory findings revealed elevated parathyroid hormone and calcium levels. ^99mTc-sestamibi SPECT imaging was performed to evaluate suspected parathyroid adenoma. Although no uptake characteristic of parathyroid adenoma was observed, a focal uptake with delayed washout was unexpectedly detected in the right frontal lobe. Subsequent MRI confirmed the lesion as a meningioma. This case underscores the diagnostic value of ^99mTc-sestamibi scintigraphy in detecting incidental cranial lesions, emphasizing its role in guiding further imaging and clinical management.