Journal of nuclear medicine technology最新文献

This study aimed to validate the effectiveness of MotionFree (MF) in the abdominal region using 2 different PET/CT scanners to determine how to use MF efficiently. Methods: All 198 patients underwent respiratory-gated ¹⁸F-FDG PET/CT with MF. Imaging was performed using Discovery MI (DMI) and Discovery IQ (DIQ) PET/CT scanners, and all data were divided into 2 groups in each category (abdominal: upper and lower abdomen, lesion size, <20 mm and ≥20 mm; scanner group: DMI and DIQ). A physician assessed whether the respiratory motion artifacts were reduced with MF. The SUV change rate (ΔSUV) of 80 measurable lesions with and without MF was calculated. The relationship between the ΔSUVs and these groups was compared. Results: Motion artifacts were reduced in 62 of 198 patients (31.3%) in the upper abdomen, in 1 of 198 patients (0.5%) in the lower abdomen, in 51 of 98 patients (52.0%) in the DMI, and in 12 of 100 patients (12.0%) in DIQ with MF. ΔSUVs were significantly higher in the upper abdomen than in the lower abdomen. ΔSUV was up to 58.3% in DMI and up to 47.6% in DIQ. ΔSUVs of lesions with a size of less than 20 mm were significantly higher than those with a lesion size of 20 mm or greater. Although DMI was more effective than DIQ in terms of motion artifacts, both DMI and DIQ have the potential to increase the SUV with MF. MF significantly reduced the respiratory motion artifacts and increased the SUV for lesions smaller than 20 mm in the upper abdomen. Conclusion: MF reduced the motion artifacts in higher-spatial-resolution PET/CT images. In both PET/CT scanners, SUVs in lesions smaller than 20 mm and lesions in the upper abdomen increased significantly with MF. To use MF without increasing the acquisition time, it may be useful to apply it to the upper abdomen.

Extragonadal choriocarcinoma in men is an extremely rare and highly aggressive malignancy. Inconclusive biopsies due to a high necrotic component often delay diagnosis. Here is such a case, in which suggestive imaging findings on [¹⁸F]FDG PET/CT, a raised level of serum β-human chorionic gonadotropin, and gynecomastia clinched the diagnosis.

Prostate cancer is a leading cause of cancer death in men. Advanced disease may progress to metastatic castration-resistant prostate cancer. In March 2022, ¹⁷⁷Lu-vipivotide tetraxetan was U.S. Food and Drug Administration-approved for patients with prostate-specific membrane antigen-positive metastatic castration-resistant prostate cancer who have previously received other therapies, including androgen deprivation and taxane therapies. Methods: Although preliminary data for ¹⁷⁷Lu-vipivotide tetraxetan has shown extension of overall survival of patients, there is little literature about realistically initiating ¹⁷⁷Lu-vipivotide tetraxetan into non-academic-based clinical practices. Results: This article presents a multidisciplinary practice implementation workflow for ¹⁷⁷Lu-vipivotide tetraxetan. It also highlights the challenges and considerations for initiating such a theranostics practice. Conclusion: The aim of this work is to help nontertiary medical centers improve patient accessibility for beneficial radiopharmaceutical therapies, specifically ¹⁷⁷Lu-vipivotide tetraxetan.

Technegas, ^99mTc-labeled aerosolized carbon nanoparticles, has been used internationally since 1986 for pulmonary ventilation imaging. Unlike traditional gases, Technegas exhibits only a gaslike behavior, allowing deep and uniform deposition in the lungs' subsegmental regions. This hydrophobic property minimizes central airway clumping, as is particularly advantageous for patients with chronic obstructive pulmonary disease. Approved by the U.S. Food and Drug Administration in September 2023, Technegas is now available in the United States for diagnosing pulmonary embolism and broader ventilation and airway evaluations. The Technegas Plus system, which produces the radioaerosol onsite by heating [^99mTc]sodium pertechnetate in a carbon crucible at ultrahigh temperatures, requires a specific infrastructure, including a 220-volt power supply and an argon gas source. Its rapid administration-often requiring only 1-3 breaths-streamlines workflows while ensuring patient comfort, especially for those with respiratory limitations. Additionally, Technegas supports SPECT and SPECT/CT imaging, enabling sensitivity and specificity superior to those of traditional planar methods. Despite the global adoption of ventilation-perfusion SPECT as the standard for pulmonary embolism diagnosis, its use in the United States remains limited. Now that Technegas is available in the United States, U.S. nuclear medicine departments can transition to advanced ventilation imaging, aligning with international best practices. This paper outlines essential considerations for Technegas implementation: infrastructure requirements, staff training, protocol development, and imaging optimization, including clinical experiences and perspectives from the staff at Barnes Jewish Hospital in St. Louis, Missouri. By integrating Technegas, departments can enhance diagnostic accuracy, improve workflow efficiency, and expand clinical applications, particularly for patients with complex pulmonary conditions.

Myocardial perfusion imaging using the radiopharmaceutical [^99mTc]Tc-tetrofosmin plays a crucial role in diagnosing cardiac conditions. However, variations in the residual activity of [^99mTc]Tc-tetrofosmin in plastic syringes after administration may impact imaging quality and patient safety. This study aimed to evaluate the residual activity of [^99mTc]Tc-tetrofosmin in plastic syringes after administration during routine nuclear medicine procedures at Hospital Kuala Lumpur, assessing compliance with department protocols and variability among different syringe brands. Methods: A single-center prospective observational study was conducted using stratified quota sampling, encompassing 396 samples across 3 syringe brands (SJ, BD, and Ciringe). Residual activity was measured immediately after administration, and statistical analysis was performed to compare brands and assess compliance with the department dosage protocol range of 333-555 MBq. Results: All injected activities aligned with the department protocol dose, with a mean effective activity of 451.23 ± 30.73 MBq and a mean residual activity of 12.63% ± 4.73%. However, variability in residual activity was observed among syringe brands. BD exhibited the highest mean residual activity (16.45%), significantly differing from SJ (9.95%) and Ciringe (11.50%) (P < 0.001). Conclusion: Rigorous syringe selection is crucial in myocardial perfusion imaging procedures to minimize residual activity and ensure compliance with dosimetry standards, emphasizing the importance of integrating pharmacy practices into nuclear medicine protocols. Standardized protocols and quality assurance measures are essential to optimize imaging outcomes and prioritize patient safety. These findings highlight the importance of ongoing monitoring and interdisciplinary collaboration to navigate residual activity management effectively in routine nuclear medicine practice.

SPECT/CT combines scintigraphy with a CT scan forming a 3-dimensional reconstruction of bone-tracer uptake patterns. It has become a fundamental component of the work-up of a painful total knee arthroplasty (TKA). The addition of an arthrogram is purported to improve its diagnostic yield. The aim of this study was to assess whether the addition of a concurrent arthrogram to a SPECT/CT enhances its sensitivity and specificity for diagnosing aseptic loosening in a painful total knee replacement. Methods: PubMed, Embase, and Scopus were searched in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Included studies compared the results of SPECT/CT with or without an arthrogram against an appropriate reference standard for diagnosing TKA aseptic loosening. The quality of included studies was independently assessed using the QUADAS-2 tool. Results: In total, 160 abstracts were identified by our search strategy. Of these, 6 studies comprising 472 patients met our inclusion criteria. All included studies used operative findings or a period of clinical and radiologic observation as reference standards. The SPECT/CT arthrogram was more sensitive in identifying aseptic loosening of knee prostheses, and it also provided greater specificity for excluding its diagnosis. Conclusion: The amalgamated results of included studies of the use of SPECT/CT demonstrate it is the best test in helping determine aseptic loosening in patients with painful TKAs (specificity, 97% vs. 85%). It is also a more sensitive test (sensitivity, 78% vs. 75%). Considering the potential morbidity of injection of contrast into the prosthetic joint, addition of an arthrogram to SPECT/CT is not beneficial and is potentially harmful.

Generative artificial intelligence (genAI) has become assimilated into the education, research, and clinical domains of nuclear medicine and health care. Understanding the principles, limitations, and applications of genAI is important for capitalizing on its transformative potential in student education and impact on sustainability within both the education and the clinical sectors. In this article, the fundamental principles and applications of artificial intelligence are explored from the context of nuclear medicine. GenAI technologies are defined and capabilities outlined. A detailed investigation of the potential and limitations of both text-to-text and text-to-image genAI based in empiric and anecdotal research is provided. Specific examples of applications of text-to-text and text-to-image genAI are provided. GenAI has the potential to reinvigorate nuclear medicine education by supporting and enriching student learning and to be transformative in nuclear medicine education, but at the time of writing, both text-to-text and text-to-image genAI are far from revolutionary. Nonetheless, the horizon promises transformative education applications of genAI. GenAI can enhance nuclear medicine education and student learning and provide economies to improve sustainability in the education and clinical sectors. Although there are some limitations to current capabilities, this rapidly evolving space will soon offer potential benefits to education.

The American Neurogastroenterology and Motility Society and the Society of Nuclear Medicine and Molecular Imaging collaboratively wrote consensus statements to standardize gastric emptying scintigraphy. Despite this, centers are using nonstandard protocols. This study examined how these protocols contrast with standards. Methods: Consecutive charts were analyzed for meal, radionuclide dose, half-emptying time (T½) and its normal range, and documented retention and emptying. Impressions were compared with how emptying mapped on a graph based on standard 4-h values. Results: Thirty-four studies were identified. Ten of 14 abnormal studies were normal when plotted on the standard 4-h graph. Eight of 10 abnormal studies had normal 2- or 4-h retention. Normal T½ ranges varied significantly. Most altered the meal, and over 25% received a radionucleotide dose outside the recommended range. Conclusion: The upper bound of normal T½ falls within standard 4-h bounds, with many individuals given an erroneous impression. Though further optimization may be needed, adhering to standards is critical.