Abnormal Biodistribution on 99mTc-Red Blood Cell-Labeled Multigated Acquisition in the Presence of Suspected Cold Agglutinin Disease.

A 99mTc-red blood cell (RBC)-labeled multigated acquisition is a procedure in which the patient's RBCs are radiolabeled and imaged with electrocardiography-gated cardiac scintigraphy to assess the heart's pumping efficiency. Cold agglutinin disease, or cold antibody autoimmune hemolytic anemia, is a rare form of autoimmune hemolytic anemia in which the body's immune system attacks and destroys its own RBCs. This case addresses an altered biodistribution pattern of radiolabeled RBCs in the presence of suspected cold agglutinin disease observed during a multigated acquisition.

ACR Appropriateness Criteria Dementia and Movement Disorders.

Neurodegenerative disease, including dementia, extrapyramidal degeneration, and motor system degeneration, is a growing public health concern and is quickly becoming one of the top health care priorities of developed nations. The primary function of anatomic neuroimaging studies in evaluating patients with dementia or movement disorders is to rule out structural causes that may be reversible. Lack of sensitivity and specificity of many neuroimaging techniques applied to a variety of neurodegenerative disorders has limited the role of neuroimaging in differentiating types of neurodegenerative disorders encountered in everyday practice. Nevertheless, neuroimaging is a valuable research tool and has provided insight into the structure and function of the brain in patients with neurodegenerative disorders. Advanced imaging techniques, such as functional neuroimaging with MRI and MR spectroscopy, hold exciting investigative potential for better understanding of neurodegenerative disorders, but they are not considered routine clinical practice at this time. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed every 3 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.

ACR Appropriateness Criteria Headache.

Most patients presenting with uncomplicated, nontraumatic, primary headache do not require imaging. When history, physical, or neurologic examination elicits "red flags" or critical features of the headache, then further investigation with imaging may be warranted to exclude a secondary cause. Imaging procedures may be diagnostically useful for patients with headaches that are: associated with trauma; new, worse, or abrupt onset; thunderclap; radiating to the neck; due to trigeminal autonomic cephalgia; persistent and positional; and temporal in older individuals. Pregnant patients, immunocompromised individuals, cancer patients, and patients with papilledema or systemic illnesses, including hypercoagulable disorders may benefit from imaging. Unlike most headaches, those associated with cough, exertion, or sexual activity usually require neuroimaging with MRI of the brain with and without contrast to exclude potentially underlying pathology before a primary headache syndrome is diagnosed. 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.

FDG-PET imaging in mild traumatic brain injury: a critical review.

Traumatic brain injury (TBI) affects an estimated 1.7 million people in the United States and is a contributing factor to one third of all injury related deaths annually. According to the CDC, approximately 75% of all reported TBIs are concussions or considered mild in form, although the number of unreported mild TBIs (mTBI) and patients not seeking medical attention is unknown. Currently, classification of mTBI or concussion is a clinical assessment since diagnostic imaging is typically inconclusive due to subtle, obscure, or absent changes in anatomical or physiological parameters measured using standard magnetic resonance (MR) or computed tomography (CT) imaging protocols. Molecular imaging techniques that examine functional processes within the brain, such as measurement of glucose uptake and metabolism using [(18)F]fluorodeoxyglucose and positron emission tomography (FDG-PET), have the ability to detect changes after mTBI. Recent technological improvements in the resolution of PET systems, the integration of PET with magnetic resonance imaging (MRI), and the availability of normal healthy human databases and commercial image analysis software contribute to the growing use of molecular imaging in basic science research and advances in clinical imaging. This review will discuss the technological considerations and limitations of FDG-PET, including differentiation between glucose uptake and glucose metabolism and the significance of these measurements. In addition, the current state of FDG-PET imaging in assessing mTBI in clinical and preclinical research will be considered. Finally, this review will provide insight into potential critical data elements and recommended standardization to improve the application of FDG-PET to mTBI research and clinical practice.

Standard versus pH-adjusted and lidocaine supplemented radiocolloid for patients undergoing sentinel-lymph-node mapping and biopsy for early breast cancer (PASSION-P trial): a double-blind, randomised controlled trial.

BACKGROUND: Sentinel-lymph-node (SLN) mapping and biopsy maintains staging accuracy in early breast cancer and identifies patients for selective lymphadenectomy. SLN mapping requires injection of technetium-99m-sulfur colloid-an effective but sometimes painful method, for which better pain-management strategies are needed. In this randomised, double-blind trial, we compared degree of pain between standard radiocolloid injection and pH-adjusted and lidocaine-supplemented formulations for patients undergoing SLN mapping for breast cancer. METHODS: Between Jan 13, 2006, and April 30, 2009, 140 patients with early breast cancer were randomly assigned in a 1:1:1:1 fashion to receive the standard topical 4% lidocaine cream and injection of [(99m)Tc]Tc-sulfur colloid (n=35), or to one of three other study groups: topical placebo cream and injection of Tc-sulfur colloid containing either sodium bicarbonate (n=35), 1% lidocaine (n=35), or sodium bicarbonate and 1% lidocaine (n=35). The randomisation sequence was computer generated, and all patients and investigators were masked to treatment allocation. The primary endpoint was patient-reported breast pain immediately after radioisotope injection, using the Wong-Baker FACES pain rating scale and McGill pain questionnaire, analysed in the per-protocol population. This study is registered with ClinicalTrials.gov, number NCT00940199. FINDINGS: 19 of the 140 patients enrolled were excluded from analysis: nine declined study participation or sought care elsewhere, nine did not undergo SLN mapping because of disease extent or a technical problem, and one had unreliable data. There were no adverse events. Mean pain scores on the Wong-Baker scale (0-10) were: 6.0 (SD 2.6) for those who received standard of practice, 4.7 (3.0) for those who received radiocolloid plus bicarbonate, 1.6 (1.4) for those who received radiocolloid plus 1% lidocaine, and 1.6 (1.3) for those who received radiocolloid plus bicarbonate and 1% lidocaine (p<0.0001). Mean pain rating, according to the McGill questionnaire (0-78), was 17.5 (SD 11.8) for the standard-of-care group, 15.4 (14.4) for the sodium bicarbonate group, 4.6 (4.5) for the 1% lidocaine group, and 3.4 (5.1) for the sodium bicarbonate plus 1% lidocaine group (p<0.0001). SLN identification rates for each group were: 96% for the standard of care, 97% for sodium bicarbonate, 90% for 1% lidocaine, and 90% for sodium bicarbonate plus 1% lidocaine group (p=0.56). INTERPRETATION: For centres that use radiocolloid injections for SLN mapping in patients with early breast cancer, the addition of 1% lidocaine to the radioisotope solution can improve patient comfort, without compromising SLN identification. FUNDING: US Military Cancer Institute, the Clinical Breast Care Project, and the Army Regional Anesthesia and Pain Management Initiative.

The added benefit of a dedicated neck F-18 FDG PET-CT imaging protocol in patients with suspected recurrent differentiated thyroid carcinoma.

PURPOSE: To retrospectively analyze whether adding a delayed high-resolution dedicated neck F-18 FDG positron emission tomography-computerized tomographic (PET-CT) imaging protocol in patients with recurrent differentiated thyroid cancer increases the number of abnormal foci within the neck. MATERIALS AND METHODS: Seventeen PET-CT studies from a total of 10 patients with suspected recurrent differentiated thyroid cancer between March 2003 and June 2004 were retrospectively reviewed. Each study included a whole body acquisition (WBA), followed by higher resolution dedicated neck acquisition (DNA). Two board-certified nuclear medicine physicians reviewed either the DNA or WBA for each study and recorded the number of abnormal foci, along with presence or absence of a soft tissue abnormality, and maximum standardized uptake value for each foci. Consensus review was used for all discrepancies. Statistical analysis was performed to determine whether there was a statistically significant increase in the number of studies demonstrating new abnormal foci with the addition of a DNA. RESULTS: Five of 17 studies demonstrated an increase in the number of abnormal foci with the addition of the DNA (P < 0.04). A total of 8 abnormal foci were noted on the WBA, 4 of which were within the neck. Eleven additional abnormal foci were seen on the DNA. All abnormal foci within the neck had corresponding soft tissue abnormalities except for one. CONCLUSION: Adding a higher resolution delayed DNA to the WBA for patients undergoing PET-CT imaging to detect recurrent thyroid cancer increases the number of abnormal sites of FDG accumulation.