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Because virtually all patients with colonic cancer will undergo some form of surgical therapy, the role of preoperative imaging is directed at determining the presence or absence of synchronous carcinomas or adenomas and local or distant metastases. In contrast, preoperative staging for rectal carcinoma has significant therapeutic implications and will direct the use of radiation therapy, surgical excision, or chemotherapy. CT of the chest, abdomen, and pelvis is recommended for the initial evaluation for the preoperative assessment of patients with colorectal carcinoma. Although the overall accuracy of CT varies directly with the stage of colorectal carcinoma, CT can accurately assess the presence of metastatic disease. MRI using endorectal coils can accurately assess the depth of bowel wall penetration of rectal carcinomas. Phased-array coils provide additional information about lymph node involvement. Adding diffusion-weighted imaging to conventional MRI yields better diagnostic accuracy than conventional MRI alone. Transrectal ultrasound can distinguish layers within the rectal wall and provides accurate assessment of the depth of tumor penetration and perirectal spread, and PET and PET/CT have been shown to alter therapy in almost one-third of patients with advanced primary rectal cancer. The ACR Appropriateness Criteria® are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment. [Copyright &y& Elsevier]

Upper-extremity venous thrombosis often presents as unilateral arm swelling. The differential diagnosis includes lesions compressing the veins and causing a functional venous obstruction, venous stenosis, an infection causing edema, obstruction of previously functioning lymphatics, or the absence of sufficient lymphatic channels to ensure effective drainage. The following recommendations are made with the understanding that venous disease, specifically venous thrombosis, is the primary diagnosis to be excluded or confirmed in a patient presenting with unilateral upper-extremity swelling. Contrast venography remains the best reference-standard diagnostic test for suspected upper-extremity acute venous thrombosis and may be needed whenever other noninvasive strategies fail to adequately image the upper-extremity veins. Duplex, color flow, and compression ultrasound have also established a clear role in evaluation of the more peripheral veins that are accessible to sonography. Gadolinium contrast–enhanced MRI is routinely used to evaluate the status of the central veins. Delayed CT venography can often be used to confirm or exclude more central vein venous thrombi, although substantial contrast loads are required. The ACR Appropriateness Criteria® are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment. [ABSTRACT FROM AUTHOR]

The diagnostic imaging of patients presenting with right lower quadrant pain and suspected appendicitis may be organized according to age and gender and to the presence or absence of “classic” signs and symptoms of acute appendicitis. Among adult patients presenting with clinical signs of acute appendicitis, the sensitivity and specificity of CT are greater than those of ultrasound, with improved performance when CT is performed with intravenous contrast. The use of rectal contrast has been associated with decreased time in the emergency department. Computed tomography has also been shown to reduce cost and negative appendectomy rates. Both CT and ultrasound are also effective in the identification of causes of right lower quadrant pain unrelated to appendicitis. Among pediatric patients, the sensitivity and specificity of graded-compression ultrasound can approach those of CT, without the use of ionizing radiation. Performing MRI after inconclusive ultrasound in pregnant patients has been associated with sensitivity and specificity of 80% to 86% and 97% to 99%, respectively. The ACR Appropriateness Criteria® are evidence-based guidelines for specific clinical conditions that are reviewed every 2 years by a multidisciplinary expert panel. The guideline development and review include an extensive analysis of current medical literature from peer-reviewed journals and the application of a well-established consensus methodology (modified Delphi) to rate the appropriateness of imaging and treatment procedures by the panel. In those instances in which evidence is lacking or not definitive, expert opinion may be used to recommend imaging or treatment. [ABSTRACT FROM AUTHOR]

Background: Thyroid lobectomy (TL) has been proposed as definitive surgical treatment for papillary thyroid cancers (PTC) up to 4 cm. This study evaluates the use and appropriateness of TL for T1b and T2 PTC.Study Design: The National Cancer Database was interrogated for adult patients having TL for T1b-T2 PTC between 2004 and 2014. Patients who should have undergone total thyroidectomy (TT) instead of lobectomy based on high-risk tumor features were identified. The 2 groups were compared for clinical and demographic characteristics, and overall survival.Results: Of 8,083 patients undergoing lobectomy, 1,552 patients had high-risk features and should have undergone TT. These included 194 with cN1, 571 with pN1, 307 with lymphovascular invasion (LVI), 645 with extra thyroidal extension (ETE), 567 with positive margins, 42 with poorly differentiated PTC, and 25 with M1 disease. At 10 years of follow-up, 92.4% of appropriate lobectomy (aTL) patients were alive compared with 88.5% of inappropriate lobectomy (iTL) patients (p < 0.001). On univariate and multivariable Cox survival analysis, age greater than 45 years, male sex, comorbidities, government or no insurance, low income, and tumor size >2 cm were associated with poorer survival (all p < 0.05). Thyroid lobectomy patients with high-risk features had significantly higher mortality on unadjusted (hazard ratio [HR] 1.98, 95% CI 1.52 to 2.59, p < 0.001) and adjusted survival analysis (HR 1.97, 95% CI 1.51 to 2.58, p < 0.001). Total thyroidectomy with radioiodine treatment had improved overall survival in comparison to iTL (HR 0.65, 95% CI 0.51 to 0.83, p < 0.001).Conclusions: A substantial number of patients (19.2%) with tumor size >1 cm and high-risk features undergo thyroid lobectomy for PTC. Exclusion of high-risk features is important when adopting lobectomy as the definitive surgical therapy for T1b and T2 PTC because they have a potential adverse effect on long-term survival. [ABSTRACT FROM AUTHOR]

Introduction: Scintigraphic evaluation of the thyroid gland enables determination of the iodine-123 iodide or the 99mTc-pertechnetate uptake and distribution and remains the most accurate method for the diagnosis and quantification of thyroid autonomy and the detection of ectopic thyroid tissue. In addition, thyroid scintigraphy and radioiodine uptake test are useful to discriminate hyperthyroidism from destructive thyrotoxicosis and iodine-induced hyperthyroidism, respectively. Methods: Several radiopharmaceuticals are available to help in differentiating benign from malignant cytologically indeterminate thyroid nodules and for supporting clinical decision-making. This joint practice guideline/procedure standard from the European Association of Nuclear Medicine (EANM) and the Society of Nuclear Medicine and Molecular Imaging (SNMMI) provides recommendations based on the available evidence in the literature. Conclusion: The purpose of this practice guideline/procedure standard is to assist imaging specialists and clinicians in recommending, performing, and interpreting the results of thyroid scintigraphy (including positron emission tomography) with various radiopharmaceuticals and radioiodine uptake test in patients with different thyroid diseases. [ABSTRACT FROM AUTHOR]

Purpose: The Society of Nuclear Medicine and Molecular Imaging (SNMMI) is an international scientific and professional organization founded in 1954 to promote the science, technology, and practical application of nuclear medicine. The European Association of Nuclear Medicine (EANM) is a professional nonprofit medical association that facilitates communication worldwide between individuals pursuing clinical and research excellence in nuclear medicine. The EANM was founded in 1985. SNMMI and EANM members are physicians, technologists, and scientists specializing in the research and practice of nuclear medicine.Methods: The SNMMI and EANM will periodically define new guidelines for nuclear medicine practice to help advance the science of nuclear medicine and to improve the quality of service to patients throughout the world. Existing practice guidelines will be reviewed for revision or renewal, as appropriate, on their fifth anniversary, or sooner, if indicated.Conclusion: Each practice guideline, representing a policy statement by the SNMMI/EANM, has undergone a thorough consensus process in which it has been subjected to extensive review. The SNMMI and EANM recognize that the safe and effective use of diagnostic nuclear medicine imaging requires specific training, skills, and techniques, as described in each document. Reproduction or modification of the published practice guideline by entities not providing these services is not authorized. [ABSTRACT FROM AUTHOR]

Purpose: Although ventilation/perfusion (V/Q) scintigraphy is a widely used imaging test, different options are possible for the acquisition and interpretation of the scan. The aim of this study was to assess current practices regarding the use and interpretation of lung scintigraphy in various clinical indications., Patients and Methods: An online survey comprising 25 questions was sent to nuclear medicine departments in Australia, Canada, France, Germany, and United States between 2022 and 2023. A single response per department was consolidated., Results: Four hundred nineteen responses were collected (Australia: 32, Canada: 58, France: 149, Germany: 92, and United States: 88). For acute pulmonary embolism (PE) diagnosis, 82.8% of centers reported using SPECT acquisitions (Australia: 93.3%, Canada: 91.8%, France: 99.2%, Germany: 96.2%, and United States: 32.1%). Among them, SPECT images were combined with a CT scan in 70.5% of centers. A total of 10.6% of centers reported not using ventilation for acute PE diagnosis. SPECT acquisition was used in 97.8% of centers using 99m Tc carbon particles, 97.1% 81m Kr gas, 58.7% 99m Tc-DTPA, and 19.4% 133 Xe gas, respectively. For V/Q SPECT interpretation, the EANM criteria were used in 65.0% of departments. A very wide variety of practices were observed in pregnant women and in COVID-19 patients. SPECT acquisition was widely used in the follow-up of PE and for the screening of chronic thromboembolic pulmonary hypertension (>90% of centers), with inconsistency regarding the interpretation of matched perfusion defects in this setting., Conclusions: This survey shows the strong adoption of SPECT in the various clinical indications of lung scintigraphy, except in the United States, where planar imaging is still mostly used. The survey also shows variability in interpretation criteria both for PE diagnosis and screening for chronic thromboembolic pulmonary hypertension, highlighting the need for further standardizations of practices., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2024 The Author(s). Published by Wolters Kluwer Health, Inc.)

Abstract: Our article addresses the prevailing trend of new terminology introduced alongside the progress being made in nuclear medicine. Our article provides a historic, current, and future perspective., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.)

Abstract: Invented and first approved for clinical use in Australia 36 years ago, Technegas is the technology that enabled ventilation scintigraphy with 99m Tc-labeled carbon nanoparticles ( 99m Tc-CNP). The US Food and Drug Administration (FDA) has considered this technology for more than 30 years but only now is getting close to approving it. Meanwhile, more than 4.4 million patients benefited from this technology in 64 countries worldwide. The primary application of 99m Tc-CNP ventilation imaging is the diagnostic evaluation for suspicion of pulmonary embolism using ventilation-perfusion quotient (V/Q) imaging. Because of 99m Tc-CNP's long pulmonary residence, tomographic imaging emerged as the preferred V/Q methodology. The FDA-approved ventilation imaging agents are primarily suitable for planar imaging, which is less sensitive. After the FDA approval of Technegas, the US practice will likely shift to tomographic V/Q. The 99m Tc-CNP use is of particular interest in the COVID-19 pandemic because it offers an option of a dry radioaerosol that takes approximately only 3 to 5 tidal breaths, allowing the shortest exposure to and contact with possibly infected patients. Indeed, countries where 99m Tc-CNP was approved for clinical use continued using it throughout the COVID-19 pandemic without known negative viral transmission consequences. Conversely, the ventilation imaging was halted in most US facilities from the beginning of the pandemic. This review is intended to familiarize the US clinical nuclear medicine community with the basic science of 99m Tc-CNP ventilation imaging and its clinical applications, including common artifacts and interpretation criteria for tomographic V/Q imaging for pulmonary embolism., Competing Interests: Conflicts of interest and sources of funding: none declared., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Osteoporosis constitutes a significant public health risk. An estimated 10.2 million adults in the United States >50 years of age have osteoporosis, a systemic condition that weakens the bones increasing the susceptibility for fractures. Approximately one-half of women and nearly one-third of men >50 years of age will sustain an osteoporotic fracture. These fractures are associated with a decrease in quality of life, diminished physical function, and reduced independence. Dual-energy X-ray absorptiometry (DXA) is the primary imaging modality used to screen for osteoporosis in women >65 years of age and men >70 years of age. DXA may be used in patients <65 years of age to evaluate bone mass density if there are additional risk factors. In certain situations, vertebral fracture assessment and trabecular bone score may further predict fracture risk, particularly in patients who are not yet osteoporotic but are in the range of osteopenia. Quantitative CT is useful in patients with advanced degenerative changes in the spine. Given the proven efficacy of pharmacologic therapy, the role of imaging to appropriately identify and monitor high-risk individuals is critical in substantially reducing osteoporosis-associated morbidity and mortality, and reducing the considerable cost to the health care system. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision process support the systematic analysis of the medical literature from peer reviewed journals. Established methodology principles such as Grading of Recommendations Assessment, Development, and Evaluation or GRADE are adapted to evaluate the evidence. The RAND/UCLA Appropriateness Method User Manual provides the methodology to determine the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where peer reviewed literature is lacking or equivocal, experts may be the primary evidentiary source available to formulate a recommendation., (Copyright © 2022 American College of Radiology. Published by Elsevier Inc. All rights reserved.)

Purpose: The aim of this study was to assess the potential role of thyroglobulin (Tg) kinetics in predicting 2-[ 18 F]-FDG-PET/CT results and overall survival (OS) in patients affected by differentiated thyroid carcinoma (DTC) and suspected recurrence., Methods: On hundred and thirty-nine patients were retrospectively included. All patients underwent 2-[ 18 F]-FDG-PET/CT due to detectable Tg levels and negative [ 131 I] whole-body scan. The last two consecutive serum Tg measurements before PET/CT were used for Tg-doubling time (TgDT) and Tg-velocity (Tg-vel) calculation. Receiver operating characteristic (ROC) curves were used to determine the optimal cutoff points for Tg, TgDT and Tg-vel for predicting PET/CT results., Results: One hundred and fifteen (83%) patients had positive PET/CT for DTC recurrence, while the remaining 24 (17%) negative. Stimulated Tg before PET and Tg-vel were significantly higher in patients with a positive PET/CT scan than negative scan (average Tg 190 vs 14 ng/mL, p = 0.006; average Tg-vel 4.2 vs 1.7 ng/mL/y, p < 0.001). Instead, TgDT was significantly shorter in positive scan (average TgDT 1.4 vs 4.4 years, p < 0.001). ROC curve analysis revealed the best Tg, TgDT and Tg-vel cutoff of 18 ng/mL,1.36 years and 1.95 ng/mL/y. In patients with Tg<18 ng/mL, the PET/CT detection rate was significantly lower in patients with low Tg-vel (p = 0.018) and with long TgDT (p = 0.001). ATA class risk, PET/CT results and Tg before PET were confirmed to be independent prognostic variables for OS., Conclusions: Tg kinetics may help to predict 2-[ 18 F]-FDG-PET/CT results in DTC patients with negative [ 131 I]WBS and detectable Tg, especially in case of low-moderate Tg., (© 2021. The Author(s).)

Objectives: The 2015 American Thyroid Association (ATA) guidelines called for significantly more selective 131 I therapy in patients with low-risk differentiated thyroid cancer (DTC). We hypothesized that application of these guidelines would significantly reduce the 131 I activity utilized by an academic tertiary hospital in Jordan., Methods: All DTC patients managed at Jordan University Hospital (JUH) between 1/2009 and 6/2019 were classified according to the 2015 ATA risk category and 131 I activity was assigned accordingly. The actual 131 I activity administered was compared with that recommended by the 2015 ATA guidelines., Results: In total, 135/182 DTC patients (74.2%) managed at JUH underwent 131 I therapy. Of those, 58 (43%) had ATA low-, 58 (43%) intermediate-, and 19 (14%) high-risk disease. The low-, intermediate-, and high-risk DTC patients received an average (±SD) initial 131 I activity of 3.53 ± 0.95, 4.40 ± 1.49, and 5.06 ± 2.52 GBq, respectively. Withholding 131 I therapy altogether in the 2015 ATA low-risk patients would result in decreasing the 131 I activity in the overall patient population by 37%. Withholding 131 I therapy only in low-risk papillary thyroid microcarcinomas while administering 1.11 GBq of 131 I to other low-risk patients would result in 28% reduction of 131 I., Conclusion: This study demonstrates a significant reduction in 131 I therapeutic activity that would be given to DTC patients in an academic tertiary setting in Jordan, following acceptance of the 2015 ATA recommendations. Institutions that adopted the 2015 ATA guidance should measure outcomes in comparison to their historical controls and report those findings, while long-term results of randomized controlled trials are forthcoming., (© 2021. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Purpose: To investigate the potential role of serum thyroglobulin doubling time (TgDT) in predicting 2-deoxy-2-[ 18 F]fluoro-D-glucose ([ 18 F]FDG) PET/CT results in patients affected by differentiated thyroid carcinoma (DTC) who demonstrated a combination of positive Tg but a negative [ 131 I] whole-body scan ([ 131 I]-WBS)., Materials and Methods: Inclusion criteria were (1) prior [ 131 I] treatment for DTC, (2) negative subsequent [ 131 I]-WBS, (3) no interfering anti-Tg antibodies, (4) three consecutive Tg measurements under the thyroid hormone replacement therapy to calculate TgDT before 2-[ 18 F]FDG PET/CT, and (5) at least 6 months of clinical and/or imaging follow-up to ascertain the diagnosis. Receiver operating characteristic (ROC) curve and the area under the curve (AUC) were used to identify the optimal cutoff point for the last stimulated Tg and TgDT prior to [ 18 F]FDG PET/CT., Results: One hundred and thirteen patients were included. Seventy-four (65%) patients had positive [ 18 F]FDG PET/CT for DTC recurrence, while the remaining 39 (35%) negative. Sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of [ 18 F]FDG PET/CT were 92%, 94%, 97%, 87%, and 93%. Patients with positive [ 18 F]FDG PET/CT had higher Tg and TgDT than those with negative PET/CT. ROC curve analysis revealed an optimal Tg cutoff of 19 ng/mL (sensitivity 78%, specificity 85%, AUC = 0.844) and TgDT of 2.5 years (sensitivity 93%, specificity 87%, AUC = 0.911). TgDT threshold of 2.5 years predicted significantly (p = 0.023) better than Tg level PET/CT results., Conclusions: The diagnostic performance of [ 18 F]FDG PET/CT could be significantly improved when TgDT is less than or equal to 2.5 years, as compared with using the absolute Tg level.

A 66-year-old man with history of papillary thyroid cancer status post total thyroidectomy underwent I-radioiodine ablation. Posttherapy I whole-body scan revealed unexpected activity within the left posterior ankle. SPECT/CT localized the radioiodine uptake to a gouty tophus in the Achilles tendon.