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Fertility medications have been postulated to increase the risk of breast cancer because of the transient but substantial elevation in hormones occurring with their use. Multiple studies exploring the relationship between fertility medications and risk of breast cancer are limited by the wide variety of fertility treatment regimens and confounded by infertility as an independent risk factor for breast cancer. The Practice Committee Guidelines of the American Society of Reproductive Medicine acknowledge that although this relationship is complex, no additional risk of breast cancer has been consistently linked to infertility medications. This article reviews the major studies both supporting and refuting this statement and makes recommendations regarding risk counseling and breast cancer screening in patients with a history of fertility treatments and infertility.

This publication reviews the current evidence supporting the imaging approach of the axilla in various scenarios with broad differential diagnosis ranging from inflammatory to malignant etiologies. Controversies on the management of axillary adenopathy results in disagreement on the appropriate axillary imaging tests. Ultrasound is often the appropriate initial imaging test in several clinical scenarios. Clinical information (such as age, physical examinations, risk factors) and concurrent complete breast evaluation with mammogram, tomosynthesis, or MRI impact the type of initial imaging test for the axilla. Several impactful clinical trials demonstrated that selected patient's population can received sentinel lymph node biopsy instead of axillary lymph node dissection with similar overall survival, and axillary lymph node dissection is a safe alternative as the nodal staging procedure for clinically node negative patients or even for some node positive patients with limited nodal tumor burden. This approach is not universally accepted, which adversely affect the type of imaging tests considered appropriate for axilla. This document is focused on the initial imaging of the axilla in various scenarios, with the understanding that concurrent or subsequent additional tests may also be performed for the breast. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Molecular breast imaging (MBI) using (99m)Tc-sestamibi has advanced rapidly over the past decade. Technical advances allow lower-dose, higher-resolution imaging and biopsy capability. MBI can be used for supplemental breast cancer screening with mammography for women with dense breasts, as well as to assess neoadjuvant therapy response, evaluate disease extent, and predict breast cancer risk. This article highlights the current state of the art and future directions in MBI.

Breast cancer screening recommendations for transgender and gender nonconforming individuals are based on the sex assigned at birth, risk factors, and use of exogenous hormones. Insufficient evidence exists to determine whether transgender people undergoing hormone therapy have an overall lower, average, or higher risk of developing breast cancer compared to birth-sex controls. Furthermore, there are no longitudinal studies evaluating the efficacy of breast cancer screening in the transgender population. In the absence of definitive data, current evidence is based on data extrapolated from cisgender studies and a limited number of cohort studies and case reports published on the transgender community. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Mammography remains the only validated screening tool for breast cancer, however, there are limitations to mammography. One of the limitations of mammography is the variable sensitivity based on breast density. Supplemental screening may be considered based on the patient’s risk level and breast density. For average-risk women with nondense breasts, the sensitivity of digital breast tomosynthesis (DBT) screening is high; additional supplemental screening is not warranted in this population. For average-risk women with dense breasts, given the decreased sensitivity of mammography/DBT, this population may benefit from additional supplemental screening with contrast-enhanced mammography, screening ultrasound (US), breast MRI, or abbreviated breast MRI. In intermediate-risk women, there is emerging evidence suggesting that women in this population may benefit from breast MRI or abbreviated breast MRI. In intermediate-risk women with dense breasts, given the decreased sensitivity of mammography/DBT, this population may benefit from additional supplemental screening with contrast-enhancedmammography or screening US. There is strong evidence supporting screening high-risk women with breast MRI regardless of breast density. Contrast-enhanced mammography, whole breast screening US, or abbreviated breast MRI may be also considered. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

PURPOSE The purposes of this study are to (1) identify patterns of inpatient PET/computed tomography (CT) use in and outside of the USA and (2) characterize inpatient PET/CT use by location and indication. MATERIALS AND METHODS The study was deemed exempt by the Institutional Review Board. A survey link through REDCap was emailed to the Society of Nuclear Medicine and Molecular Imaging (SNMMI) members and PET Centers of Excellence members and posted on the SNMMI website. Data were collected from May 2018 to August 2018. Analyses were conducted using SAS Software 9.4 with the NPAR1WAY procedure. Differences were evaluated using the Kruskal-Wallis test with statistical significance defined as P ≤ 0.05. RESULTS A total of 124 people responded to the survey, 71.8% (89/124) in the USA, and 26.6% (33/124) outside the USA [1.6% (2/124) no response]. 81.5% (101/124) read inpatient PET/CTs. Median percent of inpatient PET/CTs was 8.0% (range 0-100). Use of inpatient PET/CT was different (P

Syncope and presyncope lead to well over one million emergency room visits in the United States each year. Elucidating the cause of syncope or presyncope, which are grouped together given similar etiologies and outcomes, can be exceedingly difficult given the diverse etiologies. This becomes more challenging as some causes, such as vasovagal syncope, are relatively innocuous while others, such as cardiac-related syncope, carry a significant increased risk of death. While the mainstay of syncope and presyncope assessment is a detailed history and physical examination, imaging can play a role in certain situations. In patients where a cardiovascular etiology is suspected based on the appropriate history, physical examination, and ECG findings, resting transthoracic echocardiography is usually considered appropriate for the initial imaging. While no imaging studies are considered usually appropriate when there is a low probability of cardiac or neurologic pathology, chest radiography may be appropriate in certain clinical situations. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

A diverse health care workforce is a necessary component of equitable care delivery to an increasingly diverse US population. In nuclear medicine (NM), there is a paucity of data on the numbers of women and members of racial and ethnic groups that are underrepresented in medicine in the United States (URiMs). This study sought to: 1) characterize the current state of women and URiMs in academic nuclear medicine, 2) describe the demographics of Accreditation Council for Graduate Medical Education (ACGME) accredited NM residency program faculty and trainees, and 3) assess the extent of nuclear medicine exposure during medical school. Methods: This study was reviewed by the Institutional Review Board and deemed exempt. In this cross sectional study, a link to an online 15-item survey was emailed to 41 ACGME accredited NM residency program directors (PDs) in the United States. Data were collected between 9/2018- 12/2018 using REDCap.TM Results: 23/41 (56.1%) PDs responded to the survey, 18/23 (78.3%) male and 5/23 (21.7%) female. 3/23 (13.0%) PDs reported being URiMs. Of the 60 residents in the 23 NM residency programs whose PDs responded, 37/60 (61.7%) are male (7/37 (18.9%) URiMs) and 23/60 (38.3%) female (5/23 (21.7%) URiMs). 14/60 (23.3%) residents are US medical school graduates (US grads). PDs describe demographics of 121 current NM faculty members: 86/121 (71.1%) are male (8/121 (6.6% URIMs) and 35/121 (28.9%) female (7/121 (5.8% URiMs). 65/121 (53.7%) are US grads. 16/34 (69.6%) divisional chiefs are male, and 7/23 (30.4%) are female. 4/23 (17.4%) divisional chiefs are URiMs. 7/23 (30.4%) of NM PDs report that NM is part of the medical school curriculum. Conclusion: Women and URiMs are underrepresented in NM training programs. This diversity gap is more pronounced among NM faculty and to an even greater extent in leadership positions. A greater proportion of NM trainees are international medical graduates (IMGs) compared to NM faculty members, suggesting declining NM recruitment among US grads. NM is included in the medical school curriculum at fewer than one-third of academic centers with NM residency programs, typically toward the end of medical school. Increased and earlier exposure of NM, especially to women and URiMs, may improve recruitment and mitigate diversity gaps.

Background Nuclear medicine (NM) is a multidisciplinary field. Its overlap with nuclear radiology (NR) creates unique training considerations, opportunities, and challenges. Various factors impact the workforce, training needs, and training pathways. This state of flux may be perplexing to prospective NM/NR trainees. Purpose To evaluate the state of NM/NR training by assessing the (1) workforce trends and job prospects for NM/NR trainees, (2) NM and NR training pathways, and (3) applicant-accessible online presence of training programs. Methods Workforce trends were analyzed using data collected from the 2017 American College of Radiology Commission on Human Resources Workforce Survey. Information regarding the training pathways leading to board certification(s) for NM and NR physicians were obtained through the American Board of Nuclear Medicine, the American Board of Radiology (ABR), and the Society of Nuclear Medicine and Medical Imaging. Each Accreditation Council for Graduate Medical Education-accredited NM residency or NR fellowship training program's website was reviewed for 20 content items to assess its comprehensiveness for those seeking information regarding eligibility, applications, training curriculum, and program characteristics. Results Number of hires for NM/NR physicians has exceeded the projected number of hires from 2014 to 2017. In the last decade, there has been a greater than 25% decrease in the combined number of traditional NM residencies and NR fellowships (79–58 programs) and a greater than 50% decrease in the combined number of NM and NR trainees (173–82 trainees). In 2017, the ABR redesigned its 16-month pathway leading to specialty certification in diagnostic radiology and subspecialty certification in NR. As of March 24, 2019, there are 36 diagnostic radiology or IR residency programs with 64 trainees participating in this redesigned NR pathway. Of the 93.1% (54/58) of traditional Accreditation Council for Graduate Medical Education-accredited NM and NR training programs having websites in the 2017–2018 academic year, the mean number of online criteria met per program was 7.74 ± 3.2 of 20 (38.7%). Conclusion Recruitment into the traditional NM/NR training pathways has been steadily declining, but there has been a renewed interest with the redesigned ABR 16-month pathway. There is a paucity of online information available to prospective NM/NR applicants. In this rapidly evolving and unique field, it is important to streamline NM/NR training and bolster the information accessible to potential NM/NR applicants as they weigh career options.

Dyspnea is the symptom of perceived breathing discomfort and is commonly encountered in a variety of clinical settings. Cardiac etiologies of dyspnea are an important consideration; among these, valvular heart disease (Variant 1), arrhythmia (Variant 2), and pericardial disease (Variant 3) are reviewed in this document. Imaging plays an important role in the clinical assessment of these suspected abnormalities, with usually appropriate procedures including resting transthoracic echocardiography in all three variants, radiography for Variants 1 and 3, MRI heart function and morphology in Variants 2 and 3, and CT heart function and morphology with intravenous contrast for Variant 3. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Breakdown in communication of important imaging results threatens patient safety and risks malpractice claims. To facilitate closed-loop communication, our institution developed a unique radiology report categorization (RADCAT) system employing automated alert notification systems. This study aimed to understand users’ initial experiences with the RADCAT system and obtain feedback. Web-based surveys were distributed to radiologists and emergency department (ED) providers at our hospital system within 1 year of institution-wide RADCAT implementation. Survey designs differed based on clinical setting. Most prompts utilized declarative statements with 5-point agreement Likert scales. Closed-response data was analyzed with descriptive statistics. Response rates among radiologists and ED providers were 59.4% (63/106) and 38.4% (69/211), respectively. 78.0% (46/59) of radiologists and 60.9% (42/69) of ED providers agreed that RADCAT improves patient care. Of radiologists, 84.1% (53/63) agreed that RADCAT design is intuitive, and 57.6% (34/59) agreed that RADCAT improves efficiency. Of ED providers, 69.6% (48/69) agreed that RADCAT appropriately differentiates urgent and non-urgent findings, and 65.2% (45/69) agreed that auto-population of discharge documents with imaging results containing follow-up recommendations protects them from liability. Only 35.6% (21/59) of radiologists and 21.7% (15/69) of ED providers agreed that RADCAT implementation decreased reading room visits by ordering providers. Open-response feedback showed that some ED providers find RADCAT too complex while some radiologists desire improved transparency regarding imaging study communication status. Since its implementation, RADCAT has been well received among radiologists and ED providers with agreement that it improves patient care and effectively distinguishes and communicates important imaging findings.

Objective The Food and Drug Administration is currently creating national standards for language used in letters sent to women after mammography concerning dense breasts. The purpose of the current study is to survey breast radiologists on their opinions about language to be included in dense breast notification (DBN) letters. Methods An anonymous survey (17 questions and 10 open-ended response fields) was sent to Society of Breast Imaging members between May 2019 and June 2019. Analyses were conducted using a chi-square test and the generalized linear model. Results A total of 262 surveys were completed (25% response rate). The majority of breast radiologists believe letters should be sent to patients (91%), with most (66%) believing that patients should receive DBN letters regardless of having dense breasts or not. The majority of breast radiologists believe DBNs should be sent to referring physicians (69%), include statements that define masking (89%), inform patients that dense breasts are associated with cancer risk (77%), inform patients about the possible benefits of supplemental screening (86%), be written at the sixth- or eighth-grade reading level (92%), and should be provided in other languages in addition to English (89%); half of the respondents (51%) believe the letters should contain BI-RADS density descriptors. Conclusion There is consensus that patients and referring physicians should receive DBN letters and that those letters should address masking, increased cancer risk, and supplemental screening. Respondents believe the letters should be written at a sixth- or eighth-grade reading level.

Objective Demonstrate the psychometric evaluation process for and results from our radiology-specific patient experience measure. Methods We developed a survey to measure five dimensions of patient experience: (1) appointment, (2) reception, (3) registration, (4) procedure, and (5) facility. Each dimension included three to five questions. Each question was answered using a Likert scale (very dissatisfied to very satisfied). Data on procedure type, facility, radiologist interaction, health rating, survey length, and demographics were collected. The survey was implemented at 12 radiology offices. Analyses were conducted using responses from March 2018 to April 2019. Construct validation of the five dimensions was accomplished using confirmatory factor analysis (CFA). Internal consistency was examined using Cronbach and Guttman analysis. Results The sample included 20,736 subjects. There was strong evidence for construct validity of the five dimensions of patient experience. The CFA achieved the best fit with the five-factor model relative to other models (comparative fit index: 0.98, standardized root mean square error residual: 0.0307, root mean square error of approximation: 0.0371). There was high internal consistency (Cronbach’s α 0.94, Guttman coefficient 0.93). Item analysis showed that no questions were consistently skipped. Eighty-two percent of participants said the survey was not too long. Patients reported high satisfaction on all dimensions of satisfaction across modalities and office sites. Discussion The CFA and internal consistency analyses provide evidence for this survey having good psychometric properties: construct validity for five dimensions of patient experience and high internal consistency among the items. This survey is intended to be used by, and to benefit, radiology practices and their patients.

Objective: Compare FDG-PET/CT, CT, and bone scan for detecting and monitoring bone metastases’ response in metastatic renal cell cancer (mRCC). Methods: Patients with mRCC prospectively underwent FDG-PET/CT, CT, and bone scans at baseline and after 8 weeks of therapy. Tumor visibility and metabolic activity were retrospectively recorded. Response was evaluated by PERCIST, RECIST, and MD Anderson bone criteria. Kaplan-Meier methodology estimated event-time distributions for PFS, OS, and time to symptomatic skeletal event (SSE). Log-rank test tested differences in event-time distributions between response at 8 weeks by response criteria. Results: Sixteen patients (n = 30; 53%) were evaluable. Baseline FDG-PET/CT detected more osseous metastases (n = 55) than CT (n = 45) or bone scan (n = 34). From baseline to 8 weeks, metabolic activity of lesions decreased >20%, while qualitative and quantitative CT and bone scan parameters were unchanged for most patients. Partial metabolic responders by PERCIST had longer PFS and OS (n = 5, 20+ months) versus those with stable (n = 9; PFS = 9.2 mos, OS = 8.7 mos) and progressive (n = 2; PFS = 5.4 mos, OS = 12.1 mos) metabolic disease, p = 0.09 and 0.42, respectively. By RECIST, longer PFS and OS was seen for stable (n = 12, PFS = 8.3 mos, OS = 17.7 mos) versus progressive (n = 4; PFS = 3.7 mos, OS = 7.5 mos) disease, p = 0.16, 0.02, respectively. OS was not reached, but estimated ≥20 mos, for 4 patients with RECIST SD and PERCIST PMR, compared to OS of 17.7 mos for other patients with RECIST SD. Conclusions: FDG-PET/CT identified more bone metastases and greater numbers of quantitative and qualitative treatment responses in mRCC compared to CT and bone scan. FDG-PET/CT also may identify a sub-group of patients with better outcomes than predicted by standard imaging modalities.

Compare the BI-RADS 3 rate and follow-up of dense breast ultrasound (US) screening following digital mammography (DM) versus digital breast tomosynthesis (DBT).IRB-approved, HIPAA compliant retrospective search was performed of databases at two tertiary breast centers and an office practice for BI-RADS 3 screening US examinations performed 10/1/14-9/30/16. Prior DM versus DBT, downgrade and upgrade rate, and timing and pathology results were recorded. Differences were compared using the two-sample proportions test.3183 screening US examinations were performed, 1434/3183 (45.1%) after DM and 1668/3183 (52%) after DBT (2.5% (81/3183) no prior mammogram available). 13.9% (199/1434) had BI-RADS 3 results after DM and 10.6% (177/1668) after DBT (p 0.01). Median imaging follow-up after DM was 12 months (IQR 6, 24) versus 18 after DBT (IQR 11, 25), p = 0.02. 19.5% (73/375) of patients were lost to follow-up (19.2% (38/198) after DM (68.4% (26/38) no follow-up after initial exam) versus 19.8% (35/177) after DBT (54.3% (19/35) no follow-up after initial exam). 1.3% (5/375) of patients elected biopsy (1.5% (3/198) after DM and 1.1% (2/177) after DBT). 75.2% (282/375) of patients were downgraded (75.3% (149/198) after DM and 75.1% (133/177) after DBT). 2.5% (5/198) were upgraded after DM and 0.6% (1/177) after DBT. Median time to upgrade was 6 months after both DM and DBT. 0.3% (1/375) of patients with BI-RADS 3 results had cancer on follow-up.Patients with prior DBT had a lower risk of encountering BI-RADS 3 findings on screening ultrasound. BI-RADS 3 findings on screening ultrasound had an extremely low rate of being cancer.

To compare the motivation, deterrents, knowledge, exposure, and other specialty considerations of first- to fourth-year medical students interested in interventional radiology (IR) with those who are not.Matriculants of 5 medical schools varying by region, public/private, class size, and National Institutes of Health research ranking received a 19-question survey with questions about demographics, specialty interests, motivations/deterrents, knowledge, and exposure to IR.A total of 25.8% (611/2370) of students completed the survey, of which 20.5% (125/611) expressed interest in IR, and 25% (47/186), 26% (40/153), 24% (34/143), and 3% (3/117) of first-year, second-year, third-year, and fourth-year medical students, respectively, were seriously considering IR. Those interested in IR were less motivated by direct patient care (mean, 2.8/5; 95% confidence interval [CI], 2.6-3.0) and longitudinal patient care (mean, 1.6/5; 95% CI, 1.4-1.7) (both, P.01) and more motivated by salary (2.6/5; 95% CI, 2.3-2.9), job market (2.8/5; 95% CI, 2.6-2.9), and procedures (3.1/5; 95% CI, 2.8-3.4) compared with their peers (all P.05). Those interested in IR were more certain about their IR knowledge (mean range, 1.6-2.0/3.0; 95% CI, 1.3-2.3) than their peers (mean range, 1.9-2.4/3.0; 95% CI, 1.6-2.1, in which 0 = certain, P ≤ .01); however, both groups scored low in actual knowledge (those considering IR: 35.0-73.2% correct; 95% CI, 23.5-81.4; those who were not: 26.6-66.7% correct; 95% CI, 24.3-75.9, P.05).Although medical students showed interest in IR, they had a limited understanding of IR. IR educators may increase IR interest and understanding among medical students by clarifying the procedural aspects and longitudinal care present in a comprehensive IR practice.

Mastectomy may be performed to treat breast cancer or as a prophylactic approach in women with a high risk of developing breast cancer. In addition, mastectomies may be performed with or without reconstruction. Reconstruction approaches differ and may be autologous, involving a transfer of tissue (skin, subcutaneous fat, and muscle) from other parts of the body to the chest wall. Reconstruction may also involve implants. Implant reconstruction may occur as a single procedure or as multistep procedures with initial use of an adjustable tissue expander allowing the mastectomy tissues to be stretched without compromising blood supply. Ultimately, a full-volume implant will be placed. Reconstructions with a combination of autologous and implant reconstruction may also be performed. Other techniques such as autologous fat grafting may be used to refine both implant and flap-based reconstruction. This review of imaging in the setting of mastectomy with or without reconstruction summarizes the literature and makes recommendations based on available evidence. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

Breakdown in communication of important imaging results threatens patient safety and risks malpractice claims. To facilitate closed-loop communication, our institution developed a unique radiology report categorization (RADCAT) system employing automated alert notification systems. This study aimed to understand users' initial experiences with the RADCAT system and obtain feedback.Web-based surveys were distributed to radiologists and emergency department (ED) providers at our hospital system within 1 year of institution-wide RADCAT implementation. Survey designs differed based on clinical setting. Most prompts utilized declarative statements with 5-point agreement Likert scales. Closed-response data was analyzed with descriptive statistics.Response rates among radiologists and ED providers were 59.4% (63/106) and 38.4% (69/211), respectively. 78.0% (46/59) of radiologists and 60.9% (42/69) of ED providers agreed that RADCAT improves patient care. Of radiologists, 84.1% (53/63) agreed that RADCAT design is intuitive, and 57.6% (34/59) agreed that RADCAT improves efficiency. Of ED providers, 69.6% (48/69) agreed that RADCAT appropriately differentiates urgent and non-urgent findings, and 65.2% (45/69) agreed that auto-population of discharge documents with imaging results containing follow-up recommendations protects them from liability. Only 35.6% (21/59) of radiologists and 21.7% (15/69) of ED providers agreed that RADCAT implementation decreased reading room visits by ordering providers. Open-response feedback showed that some ED providers find RADCAT too complex while some radiologists desire improved transparency regarding imaging study communication status.Since its implementation, RADCAT has been well received among radiologists and ED providers with agreement that it improves patient care and effectively distinguishes and communicates important imaging findings.

OBJECTIVE. The purpose of this article is to review clinical uses and image interpretation of molecular breast imaging (MBI) and clarify radiation risks. CONCLUSION. MBI detects additional cancers compared with conventional imaging in women with dense breasts and those with elevated risk of breast cancer. Its role as an imaging biomarker of cancer risk and in assessing neoadjuvant chemotherapy response is growing. Radiation risk is minimal; benefit-to-risk ratio is similar to that of mammography. MBI is low cost, well tolerated, and easily adapted into clinical practice.

Purpose Effective communication of important imaging results is critical to patient care but difficult to accomplish efficiently. To improve communication at their institution, the authors introduced a radiology report categorization system (RADCAT) that organizes diagnostic imaging reports and uses automated communication systems. The study objectives were to (1) describe RADCAT’s design, (2) evaluate its implementation for appropriate imaging, and (3) evaluate the communication of important, nonurgent results with recommended follow-up. Methods This retrospective study was performed in a multihospital adult and pediatric tertiary referral academic health system. The intervention, a radiology report categorization system with five levels of acuity and IT-supported communication workflows, was globally implemented in November 2017. The primary outcomes were the successful implementation of RADCAT to appropriate diagnostic imaging reports and the successful communication of important, nonurgent results with recommended follow-up to ordering providers and patients by the radiology quality assurance team. Results Over 18 months after implementation, 740,625 radiology reports were categorized under the RADCAT system, with 42%, 28%, and 30% from the emergency department, inpatient, and outpatient settings, respectively. A random selection of 100 studies from the 23,718 total reports without RADCAT categorization identified 4 diagnostic radiology reports that erroneously lacked RADCAT grading. In 2019, of the 38,701 studies with nonurgent imaging follow-up recommendations, 38,692 (nearly 100.0%) were successfully communicated to providers or patients on the basis of quality assurance data. Conclusions A comprehensive radiology report categorization system was successfully implemented across a multihospital adult and pediatric health system, demonstrating reliable communication of imaging results with recommendations for nonacute imaging follow-up.

We present a case of a 38-year-old man with a prior episode of fever of unknown origin (FUO) four years ago who presented with acute severe dull nonradiating abdominal pain centered in the epigastric region associated with nausea and vomiting. Bloodwork showed a normal leukocyte count but elevated erythrocyte sedimentation rate of 26 and elevated C-reactive protein of 40; syphilis titers and anti-neutrophil cytoplasmic antibodies (pANCA and cANCA) were negative. CT angiogram (CTA) of the abdomen and pelvis showed diffuse medium vessel vascular inflammation. Indium-111 labeled leukocyte scan did not show evidence of infection and, specifically, no evidence of infectious vasculitis. Subsequent F18-FDG PET/CT scan showed diffuse uptake in the mesenteric vasculature in the area of abnormality seen on prior contrast-enhanced CT and confirmed the diagnosis of vasculitis, subsequently deemed by rheumatology to be most consistent with segmental arterial mediolysis.

Growing evidence suggests that 2-deoxy-2-[18F]fluoro-D-glucose (18FDG)–positron emission tomography/computed tomography (PET/CT) is a useful imaging technique for the evaluation of fever of unknown origin (FUO). This imaging technique allows for accurate localization of foci of hypermetabolism based on 18FDG uptake in glycolytically active cells that may represent inflammation, infection, or neoplasia. The presence of abnormal uptake can help direct further investigation that may yield a final diagnosis. A lack of abnormal uptake can be reasonably reassuring that these conditions are not present, thereby avoiding unnecessary additional testing. Insurers have not routinely covered outpatient 18FDG-PET/CT for the indication of FUO in the United States. However, data published since 2007 suggest early use in FUO diagnostic evaluations improves diagnostic efficiency and reduces costs. Clinicians and insurers should consider 18FDG-PET/CT as a useful tool when preliminary studies are unrevealing.

The purposes of this study were to develop an automated process for radiologists to obtain clinical follow-up on radiology reports via HIPAA-compliant e-mail and to determine what follow-up data were collected and whether they were relevant to the radiology reports.The algorithm generated high-yield follow-up data for radiologists that may improve patient care by facilitating radiologist engagement and self-assessment.

This Editorial Comment discusses the following AJR article: Background Parenchymal Uptake on Molecular Breast Imaging and Breast Cancer Risk: A Cohort Study.

The objective of this study is to present cryoablation as a minimally invasive definitive treatment for abdominal wall endometriosis. We describe our experience with the outpatient application of cryoablation to treat symptomatic abdominal wall endometriosis in three patients.This feasibility study shows that minimally invasive cryoablation treated abdominal wall endometriosis in three patients and provided a prompt clinical response.

Objective CNS toxoplasmosis and lymphoma are often indistinguishable by conventional contrast-enhanced MRI. There is limited literature on the diagnostic efficacy of dynamic susceptibility contrast (DSC) MRI for differentiating these entities. This study assesses the clinical utility of relative cerebral blood volume (rCBV) for making a diagnosis and determines rCBV thresholds for differentiation using contemporary DSC-MRI. Patients and methods Thirteen patients with 25 lesions (13 toxoplasmosis and 12 lymphoma) and pre-treatment DSC-MRI were identified retrospectively. Volumetric regions of interest of segmented enhancement were used to extract mean rCBV normalized to normal-appearing white matter for each lesion. We compared average mean rCBV between all toxoplasmosis and lymphoma lesions using a general mixed model. Three models were also compared for evaluating rCBV-based disease status in each patient: 1) mean rCBV of each lesion using a generalized estimating equation, 2) volume-weighted mean rCBV, and 3) maximum mean rCBV of all lesions using logistic regression. Results The average mean rCBV for all toxoplasmosis lesions was 0.98 (95% CI 0.55–1.41) compared to 2.07 (95% CI 1.71–2.43) for all lymphoma lesions, a significant difference (1.09, 95% CI 0.53–1.65, p = 0.0013). For the three models used to evaluate rCBV-based disease status in each patient, a significant relationship was observed, with an optimal rCBV threshold of approximately 1.5 for distinguishing lymphoma from toxoplasmosis in each model. Conclusion RCBV derived from contemporary DSC-MRI is helpful for distinguishing between cerebral toxoplasmosis and cerebral lymphoma on an individual patient basis and may facilitate more timely initiation of appropriate directed therapy.

OBJECTIVE. The purpose of this article is to review key clinical issues and imaging features of unusual pregnancy implantations. Examples from different imaging modalities are provided to increase interpreting physicians' familiarity with the appearance and potential complications of unusual ectopic, cesarean scar, heterotopic, and rudimentary horn pregnancies. CONCLUSION. Abnormal pregnancy implantations are life-threatening. Interpreting physicians' familiarity with the appearance of unusual pregnancy implantations is critical for early identification and initiation of appropriate therapy.

The goal of this project was to create a system that was easy for radiologists to use and that could reliably identify, communicate, and track communication of important but non-urgent radiology findings to providers and patients. Prior to 2012, our workflow for communicating important non-urgent diagnostic imaging results was cumbersome, rarely used by our radiologists, and resulted in delays in report turnaround time. In 2012, we developed a new system to communicate important non-urgent findings (the RADiology CATegorization 3 (RADCAT-3) system) that was easy for radiologists to use and documented communication of results in the electronic medical record. To evaluate the performance of the new system, we reviewed our radiology reports before (June 2011-June 2012) and after (June 2012-June 2014) the implementation of the new system to compare utilization by the radiologists and success in communicating these findings. During the 12 months prior to implementation, 250 radiology reports (0.06 % of all reports) entered our workflow for communicating important non-urgent findings. One-hundred percent were successfully communicated. During the 24 months after implementation, 13,158 radiology reports (1.4 % of all reports) entered our new RADCAT-3 workflow (3995 (0.8 % of all reports) during year 1 and 9163 (1.9 % of all reports) during year 2). 99.7 % of those reports were successfully communicated. We created a reliable system to ensure communication of important but non-urgent findings with providers and/or patients and to document that communication in the electronic medical record. The rapid adoption of the new system by radiologists suggests that they found it easy to use and had confidence in its integrity. This system has the potential to improve patient care by improving the likelihood of appropriate follow-up for important non-urgent findings that could become life threatening.

OBJECTIVE. The objective of this study was to compare the yield of dense breast ultrasound (US) screening after digital mammography (DM) versus after digital breast tomosyn-thesis (DBT). MATERIALS AND METHODS. For this institutional review board-approved, HIPAA-compliant study, we retrospectively searched databases at two tertiary breast imaging centers and an office practice staffed by the same fellowship-trained breast radiologists for screening US examinations from October 1, 2014, to September 30, 2016. Prior DM versus DBT and screening US and pathology results were recorded. Mammographically occult cancers detected with US and additional benign lesions requiring biopsy were calculated. Differences between DM and DBT were compared using the two-sample proportions z test. RESULTS. A total of 3183 screening breast US examinations were performed, 1434 (45.1%) after DM and 1668 (52.4%) after DBT. Of the 3183 examinations, 81 (2.5%) had no prior mammogram available. Of the 122 DM and DBT patients for whom biopsy or cyst aspiration was recommended (all BI-RADS assessment category 4 or BI-RADS assessment category 5 studies), 118 (96.7%) had biopsy or cyst aspiration results available. Of the 36 biopsies or aspirations after DM, 6 (16.7%) were malignant and 30 (83.3%) were benign; of the 82 biopsies or aspirations after DBT, 11 (13.4%) were malignant and 71 (86.6%) were benign (p = 0.8583). The additional cancer detection rate by US after DM was 5/1434 or 3.5 per 1000 women screened and after DBT was 5/1668 or 3.0 per 1000 women screened (p = 0.9999). CONCLUSION. No significant difference in additional cancer detection rate was found with screening US after DM versus after DBT.

Rationale and Objectives To evaluate readability of commonly accessed online patient educational materials (OPEM) on breast density in setting of recently passed federal breast density legislation. Materials and Methods The term “breast density” was queried using an online search engine to identify the top 50 commonly accessed websites based on order of search results on December 15, 2018. Location, cookies, and user account information were disabled prior to our query. Only websites with OPEM, defined as any educational material on breast density targeted towards the general public, were evaluated in our study. Sponsored hits and research journal articles were excluded. Available patient-directed information from websites meeting inclusion criteria was then downloaded. Grade-level readability was then determined from formatted content using generalized estimating equations, with observations nested within readability metrics from each website. Results were compared to American Medical Association recommended readability parameters (sixth-grade reading level). All interval estimates were calculated for 95% confidence. Results Fouty-one websites met inclusion criteria representing patient-directed OPEM on breast density. Average grade-level readability of health information on breast density in our study ranged from 8.5–16.5 years with an average grade reading level of 11.1 years across all websites. Of websites fitting into a specific category, academic websites had the highest average grade reading level (12.0), while nonprofit websites had the lowest average grade reading level (10.4). Nearly half (19/41) of all websites in our study had diagrams to aid in patient comprehension, while few websites (2/41; 4.8%) displayed videos in addition to written content. The website with the lowest average grade reading level was WebMD, which had an average reading level of 8.5. No individual website in our study met American Medical Association recommended parameters of a sixth-grade reading level Conclusion Readability of currently available OPEM on breast density may be written at a level too difficult for the general public to comprehend, which may represent a barrier to educational goals of newly passed federal breast density legislation.

OBJECTIVE. The purpose of this study was to compare the sensitivity, specificity, and helpfulness to referring clinicians of labeled leukocyte scintigraphy versus FDG PET/CT in inpatients with suspected infection. MATERIALS AND METHODS. In this retrospective study, labeled leukocyte scintigraphy and FDG PET/CT examinations performed from 2009 to 2017 for suspected infection in inpatients were identified. Sensitivity, specificity, and helpfulness of PET/CT versus labeled leukocyte scintigraphy were calculated by means of a mixed generalized linear model. Number of yearly tests and radiopharmaceutical costs were also assessed. RESULTS. Fifty-seven patients (30 men, 27 women; median age, 65 years; range, 21-91 years) underwent whole-body labeled leukocyte scintigraphy. Forty-two patients (30 male patients, 12 female patients; median age, 62.5 years; range, 12-91 years) underwent PET/CT for suspected infection. Labeled leukocyte scintigraphy was 66.7% sensitive, whereas the sensitivity of PET/CT was 89.7% (p = 0.0485). The higher sensitivity of PET/CT did not come at a cost to specificity, which was 73.3% as opposed to 76.9% for labeled leukocyte scintigraphy (p = 0.8050). The odds of a positive study being helpful increased 4.6-fold for PET/CT versus labeled leukocyte scintigraphy (p = 0.0412). From 2009 to 2011, 33 labeled leukocyte scintigraphic examinations were performed versus two PET/CT examinations; and from 2012 to 2014, 16 labeled leukocyte scintigraphic versus 22 PET/CT examinations; from 2015 to 2017, eight labeled leukocyte scintigraphic versus 18 PET/CT examinations. The cost of labeled leukocytes increased between 2009 and 2017, but that of FDG decreased. By 2017, a labeled leukocyte radiopharmaceutical dose was approximately 10 times the cost of an FDG dose. CONCLUSION. PET/CT was more sensitive than and as specific as labeled leukocyte scintigraphy for identifying a source of infection in inpatients, and it was more helpful to referring clinicians. Use of PET/CT increased over time and was associated with substantial savings in radiopharmaceutical cost.

Purpose To evaluate readability of websites that are commonly accessed for information on breast lesions requiring surgery. Materials and Methods An internet search using three malignant and eight nonmalignant breast lesions that traditionally require lumpectomy or excisional biopsy as search terms was conducted to identify websites commonly accessed for patient information on breast lesions requiring surgery. Nine websites with information on breast diagnoses were identified based on search engine results for each breast lesion queried. Available patient-directed information was downloaded for each lesion from each website on May 15, 2018. Grade-level readability of downloaded content for each lesion was then determined by using generalized estimating equations, with observations nested within readability metrics from each website. Readability of associated terms breast biopsy, breast cancer, and breast surgery was also evaluated with the same method. Results were compared with American Medical Association (AMA) recommended readability parameters (sixth-grade reading level). All interval estimates were calculated for 95% confidence. Results Average grade level readability score of health information on breast lesions requiring surgery was 11.7, which exceeded the AMA parameters. Information on Wikipedia was written at the highest reading level (grade level readability score, 14.2), while information on the National Institutes of Health website ( http://cancer.gov ) was written at the lowest reading level (grade level readability score, 9.7). Educational materials on malignant breast lesions (grade level readability score, 12.3) were written at a higher reading level than were those on nonmalignant breast lesions (grade level readability score,11.4). Information on the terms breast biopsy (grade level readability score, 10.9), breast cancer (grade level readability score, 10.6), and breast surgery (grade level readability score, 11.1) were all written above a sixth-grade reading level. Conclusion Readability of current online resources on breast biopsy lesions traditionally requiring surgery may be too complex for the general public to comprehend, leading to misinformation and confusion. © RSNA, 2019 See also the editorial by Haygood in this issue.

Purpose To establish, in a large cohort, the diagnostic performance of a staged algorithm involving ultrasonography (US) followed by conditional unenhanced magnetic resonance (MR) imaging for the imaging work-up of pediatric appendicitis. Materials and Methods A staged imaging algorithm in which US and unenhanced MR imaging were performed in pediatric patients suspected of having appendicitis was implemented at the authors' institution on January 1, 2011, with US as the initial modality followed by unenhanced MR imaging when US findings were equivocal. A search of the radiology database revealed 2180 pediatric patients who had undergone imaging for suspected appendicitis from January 1, 2011, through December 31, 2012. Of the 2180 patients, 1982 (90.9%) were evaluated according to the algorithm. The authors reviewed the electronic medical records and imaging reports for all patients. Imaging reports were reviewed and classified as positive, negative, or equivocal for appendicitis and correlated with surgical and pathology reports. Results The frequency of appendicitis was 20.5% (407 of 1982 patients). US alone was performed in 1905 of the 1982 patients (96.1%), yielding a sensitivity of 98.7% (386 of 391 patients) and specificity of 97.1% (1470 of 1514 patients) for appendicitis. Seventy-seven patients underwent unenhanced MR imaging after equivocal US findings, yielding an overall algorithm sensitivity of 98.2% (400 of 407 patients) and specificity of 97.1% (1530 of 1575 patients). Seven of the 1982 patients (0.4%) had false-negative results with the staged algorithm. The negative predictive value of the staged algorithm was 99.5% (1530 of 1537 patients). Conclusion A staged algorithm of US and unenhanced MR imaging for pediatric appendicitis appears to be effective. The results of this study demonstrate that this staged algorithm is 98.2% sensitive and 97.1% specific for the diagnosis of appendicitis in pediatric patients.

PET/computed tomography (CT) can evaluate the metabolic and anatomic involvement of a variety of inflammatory, infectious, and malignant cardiovascular disorders. PET/CT is useful in evaluating coronary vasculature, hibernating myocardium, cardiac sarcoidosis, cardiac amyloidosis, cerebrovascular disease, acute aortic syndromes, cardiac and vascular neoplasms, cardiac and vascular infections, and vasculitis. Novel targeted radiopharmaceutical agents and novel use of established techniques show promise in diagnosing and monitoring cardiovascular diseases.

To compare interobserver variability (IOV), reader confidence, and sensitivity/specificity in detecting architectural distortion (AD) on digital mammography (DM) versus digital breast tomosynthesis (DBT).This IRB-approved, HIPAA-compliant reader study used a counterbalanced experimental design. We searched radiology reports for AD on screening mammograms from 5 March 2012-27 November 2013. Cases were consensus-reviewed. Controls were selected from demographically matched non-AD examinations. Two radiologists and two fellows blinded to outcomes independently reviewed images from two patient groups in two sessions. Readers recorded presence/absence of AD and confidence level. Agreement and differences in confidence and sensitivity/specificity between DBT versus DM and attendings versus fellows were examined using weighted Kappa and generalised mixed modeling, respectively.There were 59 AD patients and 59 controls for 1,888 observations (59 × 2 (cases and controls) × 2 breasts × 2 imaging techniques × 4 readers). For all readers, agreement improved with DBT versus DM (0.61 vs. 0.37). Confidence was higher with DBT, p = .001. DBT achieved higher sensitivity (.59 vs. .32), p .001; specificity remained high (.90). DBT achieved higher positive likelihood ratio values, smaller negative likelihood ratio values, and larger ROC values.DBT decreases IOV, increases confidence, and improves sensitivity while maintaining high specificity in detecting AD.• Digital breast tomosynthesis decreases interobserver variability in the detection of architectural distortion. • Digital breast tomosynthesis increases reader confidence in the detection of architectural distortion. • Digital breast tomosynthesis improves sensitivity in the detection of architectural distortion.

The purpose of this study was to establish practice patterns of radiology residents in regards to interpretation and reporting of outside studies for transferred patients. We performed a national survey of radiology residency chief residents, administered by email through the Association of Program Directors in Radiology (APDR). There were 81 chief resident respondents, representing 42.8 % of 187 total Accreditation Council for Graduate Medical Education (ACGME)-approved radiology residency training programs in the USA. In 97.5 % of programs, residents perform interpretations of outside studies. Up to 76.7 % of respondents state that when outside studies are reviewed by residents, an original report is available in less than one quarter of cases. While 55.1 % of respondents state that there is a mechanism for recording their findings and impressions for outside studies, only 32.1 % are aware of a policy requiring documentation. Of the respondents, 42.3 % report they have no means for documenting their findings and impressions on outside studies. Further, 65.4 % state that there is no policy requiring an attending to review and document agreement with their interpretation of outside studies. There is wide institutional variation in both policy and practice regarding reinterpretation of outside studies for patients transferred to academic hospitals. While the majority of radiology residents are providing the service of reinterpreting outside studies, only a minority of residency programs have a policy requiring (1) documentation of their impressions or (2) attending oversight and documentation of discrepant opinions.

Fever without source is a febrile illness without localizing signs or initial obvious cause. Early workup will often include chest radiography and computed tomography (CT) of the abdomen and pelvis, with or without CT of the chest. To evaluate localizing signs or symptoms or to further evaluate findings from initial studies, targeted imaging according to body part can be performed by using radiography, ultrasonography, CT, or magnetic resonance (MR) imaging. Nuclear medicine studies can provide imaging of the whole body and may be helpful when the clinical and conventional imaging workup findings are negative or equivocal in identifying a source of fever. Nuclear medicine studies can be used to detect pathologic changes early in a disease course, even in the absence of an anatomic abnormality. Gallium 67 scintigraphy, indium 111- and technetium 99m-labeled leukocyte scintigraphy, and fluorine 18 fluorodeoxyglucose positron emission tomography (PET)/CT studies are all useful in the evaluation of fever, but the radiopharmaceutical cost for PET/CT is much lower than that for radiolabeled leukocyte studies. The increased use of bundled payments for inpatient admissions requires updated cost evaluations for the preferred nuclear medicine study. For inpatients in whom the findings from the initial clinical workup and imaging studies are nondiagnostic, PET/CT examination may be preferable to radiolabeled leukocyte studies because of its high sensitivity and lower cost. Negative findings at PET/CT can be helpful in excluding a suspected site of infection, and positive findings at PET/CT can be helpful in confirming a suspected site of infection or in identifying an unexpected cause of fever. (©)RSNA, 2016.

18F-FDG metabolic tumor volume (MTV) and total glycolytic activity (TGA) have been proposed as potential prognostic imaging markers for patient outcome in human solid tumors. The purpose of this study was to establish whether MTV and TGA add prognostic information to clinical staging in patients with oral and oropharyngeal squamous cell carcinomas (SCCs). Methods: The Institutional Review Board approved this Health Insurance Portability and Accountability Act–compliant single-institution retrospective study. Forty-five patients with histologically proven oral or oropharyngeal SCC underwent PET/CT for initial cancer staging and were included in the study. MTV was measured using a gradient-based method (PET Edge) and fixed-threshold methods at 38%, 50%, and 60% of maximum standardized uptake value (SUV). The TGA is defined as MTV × mean SUV. Bland–Altman analysis was used to establish the reliability of the methods of segmentation. Outcome endpoints were overall survival (OS) and progression-free survival. Cox proportional hazards univariate and multivariate regression analyses were performed. Results: In Cox regression models, MTV and TGA were the only factors significantly associated with survival outcome after adjusting for all other covariates including American Joint Committee on Cancer (AJCC) stage, with hazards ratio of 1.06 (95% confidence interval, 1.01–1.10; P = 0.006) and 1.00 (95% confidence interval, 1.00–1.01; P = 0.02). The model fit was significantly better when MTV was added to AJCC stage in model I (χ2 value change, 1.16–6.71; P = 0.01) and when TGA was added to AJCC stage in model II (χ2 value change, 1.16–4.37; P = 0.04). The median cutoff point of 7.7 mL for primary tumor MTV was predictive of time to OS (log rank P = 0.04). The median cutoff point of 55 g for PET Edge primary tumor TGA was predictive of time to OS (log rank P = 0.08), though the result was not statistically significant. Conclusion: Gradient-based segmentations of primary tumor MTV and TGA are potential 18F-FDG markers for time to survival in patients with oral and oropharyngeal SCC and may provide prognostic information in addition to AJCC stage. These exploratory imaging markers need validation in larger cohort studies.

We report a case series of unusual I-ioflupane SPECT imaging findings. Three patients with atypical parkinsonian symptoms underwent I-ioflupane imaging to assist in diagnosis. The patients had complete or near-complete absence of striatal activity. The imaging deficit severity did not consistently correlate with the clinical deficit severity. These cases suggest that markedly abnormal uptake patterns may be seen with atypical parkinsonian syndromes. Further research is warranted to evaluate differences in I-ioflupane uptake patterns among the various parkinsonian syndromes.

OBJECTIVE. Pancreatic cancer continues to have a poor prognosis despite impressive improvements in the outcomes of many other types of cancer, often because most pancreatic neoplasms are found to be unresectable at diagnosis. The purpose of this review is to provide an overview of pancreatic cancer and the role of modern imaging in its diagnosis and management with an emphasis on 18F-FDG PET/CT fusion imaging. CONCLUSION. Multimodality imaging is critical in the diagnosis and management of pancreatic cancer. PET/CT is increasingly viewed as a useful, accurate, and cost-effective modality in diagnosing and managing pancreatic cancer, but further studies are warranted. Early data suggest that contrast-enhanced PET/CT performed with modern PET/CT scanners yields high-resolution anatomic information for surgical and radiotherapeutic planning and functional information for whole-body staging in the care of patients with this disease.

Evidence of amodal completion exists for both visual and auditory stimuli in humans. The importance of this mechanism in forming stable representations of sensory information suggests that it may be common among multiple modalities and species. Here we show that a species of nonhuman primate amodally completes biologically meaningful acoustic stimuli, which provides evidence that the neural mechanism mediating this aspect of auditory perception is shared among primates, and perhaps other taxonomic groups as well.