Understanding the role of radiologists in complex treatment decisions for patients with hepatocellular carcinoma

Hepatocellular carcinoma (HCC) is the most common primary malignant tumor of the liver and represents a significant global health burden. Management of HCC can be challenging due to multiple factors, including variable expectations for treatment outcomes. Several treatment options are available, each with specific eligibility and ineligibility criteria, and are provided by a multidisciplinary team of specialists. Radiologists should be aware of the types of treatment options available, as well as the criteria guiding the development of individualized treatment plans. This awareness enables radiologists to contribute effectively to patient-centered multidisciplinary tumor boards for HCC and play a central role in reassessing care plans when the treatment response is deemed inadequate. This comprehensive review aims to equip radiologists with an overview of HCC staging systems, treatment options, and eligibility criteria. The review also discusses the significance of imaging in HCC diagnosis, treatment planning, and monitoring treatment response. Furthermore, we highlight the crucial branch points in the treatment decision-making process that depend on radiological interpretation.

Are Psychiatric Comorbidities in the Radiation Oncology Patient Population Under-Recognized by Providers?

PURPOSE/OBJECTIVE(S)

Under-recognition of psychiatric comorbidities may be directly tied to potential for poorer patient outcomes. However, there is a paucity of data in radiation oncology settings. This study hypothesized that a disparity exists between the perceived prevalence of psychiatric comorbidities in patients receiving radiotherapy and the rate at which radiation oncologists screen patients for anxiety and depression.

MATERIALS/METHODS

From April-July 2021 an online survey was conducted of radiation oncologist members of ASTRO with self-identified practice specializations. Randomly selected invitations were electronically sent to providers from diverse practice backgrounds and geographic locations within the United States and Canada and was conducted using an IRB-reviewed, institutionally approved Microsoft Forms platform. The questionnaire consisted of 20 items examining a broad range of factors that involved general practice demographics, patient screening practice patterns, treatment details and preferred options, and availability and referral data for specialist care for possible psychiatric comorbidities. Statistical analysis was performed using Fisher's exact test. For questions with Yes/No responses, exact binomial test was used.

RESULTS

A total of 500online invitations were emailed with 55 responses. Of the responders, 3 did not provide consent. Therefore, 52 (10.4%) responses were included in the analysis and are the subject of this report. This response rate is consistent with other published studies of this type. 85% (p<0.001) of respondents identified the need to screen for psychiatric comorbidities in radiation oncology settings. However, 71% (p = 0.003) did not perform formal screening for psychiatric comorbidities, and of those who did screen, there was no uniformity in the screening tool utilized. Likewise, 79% (p<0.001) did not initiate treatment for psychiatric condition(s). Of providers that did initiate treatment, 91% (p = 0.012) felt that psychiatric comorbidities were under-diagnosed in their patient population. No association was made between providers who specialize in CNS malignancies as being more likely to recognize psychiatric comorbidities in their patient population versus those who do not. Importantly, 75% self-reported that they would benefit from additional training to assess psychiatric comorbidities (p<0.001).

CONCLUSION

A need to screen for psychiatric comorbidities in radiation oncology settings was identified despite very little formal screening performed. Responses revealed adequate community resources exist for referral in most instances. However, providers did not routinely refer patients for treatment of psychiatric comorbidities, even when recognized. This survey identified an unmet need for improved education among providers to engage in screening and referral for psychiatric comorbidities, and to develop a care system that supports standardization of screening practices and tools in this patient population.

"Learning From Disaster: What Past Events Can Teach Radiology Departments about Planning for a Mass Casualty Incident"

The increased frequency of mass shootings, terror attacks, and natural disasters in recent years have presented challenges to provision of quality medical care in both short and long-term stressful situations. While emergency departments and trauma surgeons are usually the face of the response to mass casualty incidents (MCI), other departments such as radiology are often active participants in caring for these patients but may not be as well prepared. In this article, we review nine papers describing the experiences of various radiology departments with specific MCIs and the lessons they learned from those experiences. By analysis of common themes raised in these papers, we hope to enable departments to incorporate these lessons into their disaster plans to enhance their preparedness for such events.

The adoption of LI-RADS: a survey of non-academic radiologists

PURPOSE

To understand the practice and determinants of non-academic radiologists regarding LI-RADS and the four current LI-RADS algorithms: CT/MRI, contrast-enhanced ultrasound (CEUS), ultrasound (US), and CT/MRI Treatment Response.

MATERIALS AND METHODS

Seven themes were covered in this international survey, as follows: (1) demographics of participants and sub-specialty, (2) HCC practice and interpretation, (3) reporting practice, (4) screening and surveillance, (5) HCC imaging diagnosis, (6) treatment response, and (7) CT and MRI technique.

RESULTS

Of the 232 participants, 69.4% were from the United States, 25.0% from Canada, and 5.6% from other countries and 45.9% were abdominal/body imagers. During their radiology training or fellowship, no formal HCC diagnostic system was used by 48.7% and LI-RADS was used by 44.4% of participants. In their current practice, 73.6% used LI-RADS, 24.7% no formal system, 6.5% UNOS-OPTN, and 1.3% AASLD. Barriers to LI-RADS adoption included lack of familiarity (25.1%), not used by referring clinicians (21.6%), perceived complexity (14.5%), and personal preference (5.3%). The US LI-RADS algorithm was used routinely by 9.9% of respondents and CEUS LI-RADS was used by 3.9% of the respondents. The LI-RADS treatment response algorithm was used by 43.5% of the respondents. 60.9% of respondents thought that webinars/workshops on LI-RADS Technical Recommendations would help them implement these recommendations in their practice.

CONCLUSION

A majority of the non-academic radiologists surveyed use the LI-RADS CT/MR algorithm for HCC diagnosis, while nearly half use the LI-RADS TR algorithm for assessment of treatment response. Less than 10% of the participants routinely use the LI-RADS US and CEUS algorithms.

NOD1 mediates interleukin-18 processing in epithelial cells responding to Helicobacter pylori infection in mice

The interleukin-1 family members, IL-1β and IL-18, are processed into their biologically active forms by multi-protein complexes, known as inflammasomes. Although the inflammasome pathways that mediate IL-1β processing in myeloid cells have been defined, those involved in IL-18 processing, particularly in non-myeloid cells, are still not well understood. Here we report that the host defence molecule NOD1 regulates IL-18 processing in mouse epithelial cells in response to the mucosal pathogen, Helicobacter pylori. Specifically, NOD1 in epithelial cells mediates IL-18 processing and maturation via interactions with caspase-1, instead of the canonical inflammasome pathway involving RIPK2, NF-κB, NLRP3 and ASC. NOD1 activation and IL-18 then help maintain epithelial homoeostasis to mediate protection against pre-neoplastic changes induced by gastric H. pylori infection in vivo. Our findings thus demonstrate a function for NOD1 in epithelial cell production of bioactive IL-18 and protection against H. pylori-induced pathology.

Current state of peer learning in radiology- A survey of American College of Radiology members

PURPOSE

Peer learning (PL) programs seek to improve upon the limitations of score-based peer review and incorporate modern approaches to improve patient care. This study seeks to further understand the landscape of peer learning among members of the American College of Radiology in the first quarter of 2022.

METHODS

Members of the American College of Radiology (ACR) were surveyed to evaluate the incidence, current practices, perceptions, and outcomes of PL in radiology practice. The survey was administered via email to 20,850 ACR members. The demographic and practice characteristics of the 1,153 (6%) respondents were similar to the ACR radiologist membership and correspond to a normal distribution of the population of radiologists and can therefore be described as representative of that population. Therefore, the error range for the results from this survey is +/- 2.9% at a 95% confidence level.

RESULTS

Among the total sample, 610 (53%) respondents currently use PL, 334 (29%) do not. Users of PL are younger (mode age 45-54 for users, 55-64 for non-users, P<0.01), more likely to be female (29% vs 23%, P<0.05), and more likely to practice in urban settings (52% vs 40%, P= 0.0002). Users of PL feel it supports an improved culture of safety and wellness (543/610, 89%) and fosters continuous improvement initiatives (523/610, 86%). Users of PL are more likely than non-users to identify learning opportunities from routine clinical practice (83% vs. 50%, P<0.00001), engage in programming inclusive of more team members, and implement more practice improvement projects (P<0.00001). PL users' net promoter score of 65% strongly suggests that users of PL are highly likely to recommend the program to colleagues.

DISCUSSION

Radiologists across a breadth of radiology practices are engaged in peer learning activities, which are perceived to align with emerging principles of improving healthcare and enhance culture, quality, and engagement.

Pitfalls and Practical Challenges in Imaging of the Pediatric Scrotum

ABSTRACT

Ultrasound is the modality of choice for evaluation of the pediatric scrotum, as it provides excellent image quality without the use of radiation, need for sedation/anesthesia, or use of contrast material and can be used for serial examination. Ultrasound of the scrotum has proven to be useful for assessment of a wide gamut of congenital, infectious, inflammatory, endocrine, neoplastic, and traumatic abnormalities in pediatric patients of all ages from the tiniest premature infant to a fully grown young adult. This review article presents a varied spectrum of conditions that may affect the pediatric scrotum, what the radiologist needs to know to meet the challenge of limiting the differential diagnosis, and how to avoid pitfalls when imaging the scrotum.

The role of an alpha-selective phosphoinositide-3 kinase inhibitor in vascular inflammation

Funding Acknowledgements

Type of funding sources: Public Institution(s). Main funding source(s): British Heart Foundation

Introduction

Cardiovascular inflammation is associated with endothelial cell (EC) damage, resulting in leukocyte trafficking and oedema formation. Inflammation disrupts EC junctions, increasing microvascular permeability, and resulting in a positive-feedback loop of inflammatory events. The phosphoinositide 3-kinase pathway stimulates this endothelial response and this study examined the actions of BYL-719, a PI3K-α selective inhibitor, on inflammatory responses.

Method

Confocal imaging using immunofluorescence and permeability assays were undertaken to quantify the effect of inflammatory cytokines, TNF-α and IL-1β, in the presence of the PI3K inhibitor using fluorescein isothiocyanate-dextran (40 kDa, 0.1 mg/ml) on human microvascular endothelial cells (HMVEC) (Lonza, derived from dermal tissue). Cells were treated with either cytokine for 16-18 h, followed by a 1 h treatment of drug and a final 1 h treatment with FITC-dextran. In vivo analysis was carried out per the UK Home Office Animals (Scientific Procedures) Act 1986. Male WT CD1 mice were anaesthetised initially using 5% isoflurane and maintained at 2% for procedures, to test BYL-719 in a model of dorsal skin inflammation, to determine neutrophil accumulation (measured by myeloperoxidase) and oedema formation (measured by Evans Blue accumulation). All statistical significance was determined using one-way or two-way ANOVA followed by Tukey’s post hoc test.

Results

BYL-719 significantly reduced cytokine-induced EC permeability and shape changes, including cell area and elongation (Table 1), impeding in vitro cytokine-induced inflammation. The inhibitor, abrogated effects of the inflammatory cytokines in vivo of both TNF-α and IL-1β, but interestingly had no effect on the neutrophil accumulation or oedema formation in the presence of C5a (Figure 1).

Figure 1: The effect of BYL-719 in the dorsal skin inflammation model. Mice were pre-treated with 50 mg/kg BYL-719 intraperitoneally for 30 min, injected intravenously with Evans Blue dye, intradermally injected with TNF-α (100ng/50ul), IL-1β (10ng/50ul) and C5a (300ng/50ul) for 4 h, followed by ex vivo MPO assay (A) and oedema volume measurements (B). Data are mean ±SEM two-way ANOVA by Tukey test., n=6 independent experiments in duplicates; p* &lt; 0.05 and p**** &lt; 0.0001 between control (DMSO) and BYL-719 treated groups.

Conclusions

Our findings show that the PI3K-α inhibitor, BYL-719, reduces endothelial activation and inhibits inflammatory oedema formation in the presence of TNF-α and IL-1β. We conclude that there is a potential for PI3K inhibitors to act as anti-neutrophil and oedema agents in cardiovascular-related inflammatory conditions.

Mastocytosis-A Review of Disease Spectrum with Imaging Correlation

Simple Summary

In this review will discuss the clinical presentation, pathophysiology, and role of imaging in detection and extent estimation of the systemic involvement of the disease, in addition to demonstration of appearance on varying imaging modalities. Familiarity with the potential imaging findings associated with mastocytosis can aid in early disease diagnosis and classification and accordingly can lead directing further work up and better management.

Abstract

Mastocytosis is a rare disorder due to the abnormal proliferation of clonal mast cells. Mast cells exist in most tissues, mature in situ from hematopoietic stem cells and develop unique characteristics of local effector cells. Mastocytosis develops by activation mutation of the KIT surface receptor which is involved in the proliferation of a number of cell lines such as mast cells, germ cells, melanocytes, and hematopoietic cells. It manifests as two main categories: cutaneous mastocytosis and systemic mastocytosis. Imaging can play an important role in detection and characterization of the disease manifestation, not only by radiography and bone scans, but also magnetic resonance imaging and computed tomography, which can be more sensitive in the assessment of distinctive disease patterns. Radiologists should be aware of various appearances of this disease to better facilitate diagnosis and patient management. Accordingly, this review will discuss the clinical presentation, pathophysiology, and role of imaging in detection and extent estimation of the systemic involvement of the disease, in addition to demonstration of appearance on varying imaging modalities. Familiarity with the potential imaging findings associated with mastocytosis can aid in early disease diagnosis and classification and accordingly can lead directing further work up and better management.

Identification of locally isolated entomopathogenic Fusarium species from the soil of Changa Manga Forest, Pakistan and evaluation of their larvicidal efficacy against Aedes aegypti

Dengue fever vectored by the mosquito Aedes aegypti is one of the most rapidly spreading insect-borne diseases. Current reliance of dengue vector control is mostly on chemical insecticides. Growing insecticide resistance in the primary mosquito vector, Aedes aegypti, limits the effectiveness of vector control through chemical insecticides. These chemical insecticides also have negative environmental impacts on animals, plants and human health. Myco-biocontrol agents are naturally occurring organisms and are found to be less damaging to the environment as compared to chemical insecticides. In the present study, entomopathogenic potential of local strains of fungi isolated from soil was assessed for the control of dengue vector. Local fungal isolates presents better alternative to introducing a foreign biocontrol strain, as they may be better adapted to environmental conditions of the area to survive and may have more entomopathogenic efficacy against target organism. Larvicidal efficacy of Fusarium equiseti and Fusarium proliferatum was evaluated against Aedes aegypti. Local strains of F. equiseti (MK371718) and F. proliferatum (MK371715) were isolated from the soil of Changa Manga Forest, Pakistan by using insect bait method. Larvicidal activity of two Fusarium spp. was tested against forth instar larvae of A. aegypti in the laboratory, using concentrations 105, 106, 107 and 108 conidia /ml. LC50 values for F. equiseti after 24h, 48h, 72h and 96h of exposure were recorded as 3.8x 108, 2.9x107, 2.0x107, and 7.1x106 conidia /ml respectively while LC50 values for F. proliferatum were recorded as 1.21x108, 9.6x107, 4.2x107, 2.6x107 conidia /ml respectively after 24h, 48h, 72h and 96h of exposure. The results indicate that among two fungal strains F. equiseti was found to be more effective in terms of its larvicidal activity than F. proliferatum against larvae of A. aegypti.

885 Telephone Consultations During the Covid-19 Pandemic; from the Perspective of One Oral and Maxillofacial Unit

Introduction

The Covid-19 pandemic has had a global impact on healthcare. As a result, changes have been made to healthcare provision. In the UK, the focus was changed to urgent and emergency treatment only, and therefore a shift from face-to-face consultations to video and telephone consultations was implemented. Our aim was to look at the telephone consultations in our oral and maxillofacial (OMF) department to identify their effectiveness.

Method

A search was carried out using the electronic patient record for patients booked for consultations in the OMF clinics from the 23^rd of March to the 1^st of May 2020. Trauma clinics and ad-hoc clinics were excluded.

Results

21 clinic codes were found as suitable for inclusion. 185 consultations were booked during the 6-week period. Of these, 165 were via telephone and 20 face-to-face. A total of 75 consultations resulted in discharge and 110 required further follow up or further investigation. Of the 75 patients discharged, 73 of these were via telephone. The main reason for discharge was delivery of benign biopsy results.

Conclusions

Covid-19 will have long term impacts on healthcare provision. If implemented correctly, virtual consultations carry the potential in making healthcare more accessible.

Trauma CT evaluation prior to selective angiography in patients with traumatic injuries: negative predictive power and factors affecting its utility

PURPOSE

To evaluate the predictive power of arterial injury detected on contrast-enhanced CT (trauma CT (tCT)) imaging obtained prior to selective angiography for treatment of patients with traumatic abdominal and pelvic injuries.

MATERIALS AND METHODS

A retrospective chart review was performed of all patients who underwent angiography after undergoing contrast-enhanced CT imaging for the evaluation/treatment of traumatic injuries to the abdomen and pelvis between March 2014 and September 2018. Data collection included demographics, pertinent history and physical findings, CT and angiography findings, treatment information, and outcomes.

RESULTS

Eighty-nine (63 males, mean age = 45.8 ± 20.5 years) patients that were found to have 102 traumatic injuries on tCT and subsequently underwent angiography met inclusion criteria for this study. Sixty-four injuries demonstrated evidence of traumatic vascular injury on initial tCT. A negative tCT was able to predict subsequent negative angiography in 83% of cases (negative predictive power = 83%). The ability of tCT to rule out a positive finding on subsequent angiography was also 83% (sensitivity = 83%). The average systolic blood pressure and hemoglobin concentration at the time of tCT were higher in patients who had positive tCT than in patients with negative tCT (p < 0.05 and p < 0.01, respectively). The average time to angiography was greater in patients whom had subsequent negative angiography than the patients who had subsequent positive angiography (p < 0.05).

CONCLUSION

Contrast-enhanced CT imaging may be able to help stratify patients who may have subsequent negative angiograms. Hemodynamic factors may affect sensitivity of tCT. Shorter time to angiography may increase the chance of identifying the injury on subsequent angiography.

Forty-One Million RADPEER Reviews Later: What We Have Learned and Are Still Learning

ACR RADPEER® is the leading method of radiologic peer review in the United States. The program has evolved since its inception in 2002 and was most recently updated in 2016. In 2018, a survey was sent to RADPEER participants to gauge the current state of the program and explore opportunities for continued improvement. A total of 26 questions were included, and more than 300 practices responded. In this report, the ACR RADPEER Committee authors summarize the survey results and discuss opportunities for future iterations of the RADPEER program.

P701The role of a phosphoinositide-3 kinase inhibitor in vascular inflammation

Background/Introduction

Cardiovascular inflammation is associated with endothelial damage, resulting in leukocyte trafficking and oedema formation, which results in a positive-feedback loop of inflammatory events.

Purpose

The phosphoinositide 3-kinase (PI3K) pathway has been shown to be upregulated in vascular disease conditions whereby its inhibitors potentially have beneficial effects. Hence this study was designed to examine the actions of PI-103, a PI3K non-selective inhibitor, on inflammatory responses.

Methods

Permeability assays were undertaken to quantify the effect of TNF-a in the presence and absence of PI-103 using FITC-dextran (40 kDa, 0.1 mg/ml) to measure levels of permeability in trans-wells plates using human microvascular endothelial cells (HMVEC).

In vivo analysis was carried out per the UK Home Office Animals (Scientific Procedures) Act 1986. CD1 mice were anaesthetised, to test PI-103 in a zymosan-induced model of dorsal skin inflammation on neutrophil accumulation (measured by myeloperoxidase) and oedema formation (measured by Evans Blue accumulation).

All data were analysed using 1-way or 2-way ANOVA with post-hoc test.

Results

PI-103 significantly reduced TNF-α induced microvascular endothelial cell permeability (Graph), thus impeding in vitro cytokine-induced inflammation. Whilst there was no effect on neutrophil accumulation in vivo, there was significant reduction in weight of treated areas and oedema formation, which was inhibited by PI-103 (Table 1).

Effect of PI-103 in vivo Control 30 mg/kg PI-103 Tyrode solution Zymosan (μg/ml) Tyrode solution Zymosan (μg/ml) 10 30 100 10 30 100 MPO/Protein (U/mg) 0.66±0.26 1.42±0.07 1.40±0.14 1.68±0.12* 0.60±0.11 1.23±0.32 1.36±0.25 1.59±0.21* Oedema Volume (mm3) 0.00±0.00 3.26±1.76 11.70±2.21 21.50±4.67 2.20±1.53 1.05±1.05 3.27±0.74 5.52±1.58 Mice were pre-treated with PI-103 i.p. for 30 min, i.d injected with zymosan (50 μl/site) for 4 hr, followed by ex vivo MPO assay, weight and oedema volume measurements. Oedema was quantified by measuring: width (x), height (y) and depth (z) from each of the i.d. sites; volume of oedema = ((π/6)xyz). N=6 independent experiments in duplicates; *p<0.05 between Tyrode solution vs zymosan groups.

Effect of PI103 in vitro on permeability

Conclusions

Our findings show that the PI3K non-selective inhibitor, PI-103 (as well as a PI3K α-selective inhibitor), reduces endothelial activation and inhibits inflammatory oedema formation. We conclude that there is a potential for PI3K inhibitors to act as anti-oedema agents in cardiovascular-related inflammatory conditions.

Acknowledgement/Funding

British Heart Foundation

White paper of the Society of Abdominal Radiology hepatocellular carcinoma diagnosis disease-focused panel on LI-RADS v2018 for CT and MRI

The Liver Imaging and Reporting Data System (LI-RADS) is a comprehensive system for standardizing the terminology, technique, interpretation, reporting, and data collection of liver imaging with the overarching goal of improving communication, clinical care, education, and research relating to patients at risk for or diagnosed with hepatocellular carcinoma (HCC). In 2018, the American Association for the Study of Liver Diseases (AASLD) integrated LI-RADS into its clinical practice guidance for the imaging-based diagnosis of HCC. The harmonization between the AASLD and LI-RADS diagnostic imaging criteria required minor modifications to the recently released LI-RADS v2017 guidelines, necessitating a LI-RADS v2018 update. This article provides an overview of the key changes included in LI-RADS v2018 as well as a look at the LI-RADS v2018 diagnostic algorithm and criteria, technical recommendations, and management suggestions. Substantive changes in LI-RADS v2018 are the removal of the requirement for visibility on antecedent surveillance ultrasound for LI-RADS 5 (LR-5) categorization of 10-19 mm observations with nonrim arterial phase hyper-enhancement and nonperipheral "washout", and adoption of the Organ Procurement and Transplantation Network definition of threshold growth (≥ 50% size increase of a mass in ≤ 6 months). Nomenclatural changes in LI-RADS v2018 are the removal of -us and -g as LR-5 qualifiers.

Design and execution of clinical trials in orthopaedic surgery

High-quality randomised controlled trials (RCTs) evaluating surgical therapies are fundamental to the delivery of evidence-based orthopaedics. Orthopaedic clinical trials have unique challenges; however, when these challenges are overcome, evidence from trials can be definitive in its impact on surgical practice. In this review, we highlight several issues that pose potential challenges to orthopaedic investigators aiming to perform surgical randomised controlled trials. We begin with a discussion on trial design issues, including the ethics of sham surgery, the importance of sample size, the need for patient-important outcomes, and overcoming expertise bias. We then explore features surrounding the execution of surgical randomised trials, including ethics review boards, the importance of organisational frameworks, and obtaining adequate funding. Cite this article: Bone Joint Res 2014;3:161-8.

Insulin and extremity muscle mass in overweight and obese women

Obesity disproportionately affects women, especially those of African descent, and is associated with increases in both fat and muscle masses. Although increased extremity muscle mass may be compensatory to fat mass load, we propose that elevated insulin levels resulting from diminished insulin sensitivity may additionally contribute to extremity muscle mass in overweight or obese women. The following measurements were performed in 197 non-diabetic women (57% black, 35% white; age 46±11 years [mean±SD], BMI range 25.0 to 57.7 kg/m²): dual-energy X-ray absorptiometry for fat and extremity muscle masses; exercise performance by duration and peak oxygen consumption (VO₂ peak) during graded treadmill exercise; fasting insulin and in 183 subjects insulin sensitivity index (S_I) calculated from the minimal model. S_I (range 0.5 to 14.1 liter/mU⁻¹•min⁻¹) was negatively, and fasting insulin (range 1.9 to 35.6 μU/mL) positively, associated with extremity muscle mass (both P<0.001), independent of age and height. Sixty-seven percent of women completed 6 months of participation in a weight loss and exercise program: We found a significant association between reduction in fasting insulin and a decrease in extremity muscle mass (P=0.038), independent of reduction in fat mass or improvement in exercise performance by VO₂ peak and exercise duration, and without association with change in S_I or interaction by race. Thus, hyperinsulinemia in overweight or obese women is associated with increased extremity muscle mass, which is partially reversible with reduction in fasting insulin concentration, consistent with stimulatory effects of insulin on skeletal muscle.

Indian Radiologists in the United States: Hierarchical Distribution and Representation

PURPOSE

To evaluate both the distribution of radiologists of Indian ancestry and nativity in the United States in training and beyond and their representation in hierarchal positions in major radiology organizations.

MATERIALS AND METHODS

The annual membership lists of the Radiological Society of North America (RSNA) and the ACR over the past decade were analyzed for the number and locations of radiologists of Indian ancestry or nativity. To evaluate the progression and current extent of enrollment of members of this cohort in positions of leadership in radiology organizations, their overall membership and their specific participation in RSNA and ACR committees were tabulated. Their listing in the latest directories of chairpersons and program directors in radiology was assessed. The distribution of ethnic Indian radiologists in training was calculated by examining resident rosters by academic program and state.

RESULTS

Since the passage of the Immigration and Nationality Act of 1965, individuals of Indian ancestry have constituted a growing minority of radiologists. In 2002, they constituted 5.5% of all RSNA members. Recently, their numbers in training programs have increased greatly. They are now estimated to constitute 13.3% of all residents, predominantly because of the entry of the American-born offspring of Indian immigrants. Yet ethnic Indians are markedly underrepresented in the hierarchy of major radiology organizations. In both 1999 and 2003, there were no Indian-surnamed representatives on most major committees and none in board-level positions of both the ACR and the RSNA. The number of radiologists of Indian birth or background who are program directors has increased slightly over the past 10 years from 2:196 (1%) in 1993 to 7:196 (3.5%) in 2003. The representation of radiologists of Indian ethnicity on the mastheads of both the American Journal of Roentgenology and Radiology remains meager; fewer than 2% of these journals' assistant editors and editors are of Indian ethnicity.

CONCLUSION

The percentage of radiologists identifiable as Indian by nativity or ethnicity is growing rapidly, predominantly because of an increase in the number of American-born trainees. Yet only a few more senior members of this group have secured positions of leadership in the specialty, restricting the number of ethnically similar role models for Indian junior members of the specialty to emulate.

Feasibility of real-time 3-dimensional treadmill stress echocardiography

Rapid acquisition of echocardiographic images is critical for the predictive accuracy of stress echocardiography. Real-time 3-dimensional echocardiography (RT3D) allows review of several standard 2-dimensional images from a single volumetric data set. To assess the feasibility of RT3D for treadmill stress echocardiography, we performed treadmill stress RT3D on 20 volunteers (10 men and 10 women; mean age 32 +/- 6 years) with a device that uses a matrix phased-array transducer in a 60-degree pyramidal volume. Images are displayed as 2 steerable, intersecting B-scan sectors with adjustable C-scan planes parallel to the transducer face. At pre-exercise and immediate postexercise assessment, the volumetric data were obtained from apical and parasternal windows, respectively. Left ventricular segments were divided into 16 standard segments according to criteria defined by the American Society of Echocardiography. The use of both volume sets resulted in visualization of 98% of the segments at peak exercise. Even with only an apical volume set, 89% of the segments were adequately visualized. Image optimization and acquisition time at peak exercise was 35 +/- 18 seconds from the apical window and 50 +/- 28 seconds from the parasternal window. This preliminary study indicates that RT3D treadmill stress echocardiography is feasible and may be an important application of this new 3-dimensional device.

Real-time, 3-dimensional echocardiography acquires all standard 2-dimensional images from 2 volume sets: a clinical demonstration in 45 patients

To test the hypothesis that real-time, 3-dimensional (3-D) echocardiography can obtain all standard 2-dimensional (2-D) views from acquisition of 2 volume sets, we scanned 45 patients (24 men, 21 women; mean age 49 +/- 17 years). This real-time 3-D device (VOLUMETRICS Medical Imaging, Durham, NC) uses a matrix phased array transducer in a 60 degree pyramidal volume. Images are displayed as 2 steerable, intersecting, conventional 2-D image sectors that can be oriented throughout 3-D space. By using this equipment, we were able to obtain 93.3% of standard views from a parasternal volume set and 85.2% of standard views from an apical volume set. The mean scanning time was 91 +/- 19 seconds for the parasternal volume set and 86 +/- 22 seconds for the apical volume set. We conclude that standard 2-D views can be obtained in the majority of patients by using this method. This equipment has the potential to substantially decrease the imaging time compared with the standard 2-D echocardiography.

Comparison of graded versus constant treadmill test protocols for quantifying intermittent claudication

The standard method for quantifying the symptoms of intermittent claudication is by using treadmill walking distance. It has recently been suggested that a graded exercise test is much more reproducible than a constant load exercise test. Graded protocols have also been claimed to abolish the placebo effect that has been reported with the constant load test. The reproducibility of absolute claudication distance (ACD) and initial claudication distance (ICD) using a constant load was compared to the graded load treadmill protocol. Fourteen patients (mean age 66 years) with varying severity of stable intermittent claudication were tested using a constant load (3.2 km/h, 10% gradient) and a graded load (3.2 km/h, 0% gradient increasing by 3.5% every 3 min). Patients were tested twice using each protocol in a random sequence, with a minimum 2 day interval between visits. Intra-class correlation coefficient (R) with a constant load protocol for ICD and ACD was R = 0.68, R = 0.93, respectively. With a graded protocol R = 0.84 for ICD and R = 0.98 for ACD. Relative coefficient of repeatability for ICD and ACD during constant load tests were 1.47 and 1.90 respectively and with a graded load test were 1.69 and 1.52 respectively. It was concluded that the graded load test was more reproducible than the constant load test but only by a small margin, whilst ACD was much more reproducible than ICD using either protocol.

Repeatability of intravital capillaroscopic measurement of capillary density

The reliability of intravital capillaroscopy for determining capillary density (CD) of skin has been questioned because it depends upon the variability of the measuring process and subjective interpretation of data as well as the intrinsic heterogeneity of capillary spacing. The aim of this study was to assess the repeatability of a standardised method for measuring CD of the skin of the dorsum of foot. In each of 30 subjects (10 controls and 20 patients with peripheral vascular disease), the foot was systematically mapped by examining 20 sites on the dorsum of foot and 2 sites on each toe, using white light (native) videomicroscopy at 40 x magnification. Off-line analysis of videoprints was then undertaken to determine CD at each site, by counting capillaries within areas of acceptable photographic quality only, having first defined the criteria for counting capillaries. The mean values were then calculated and taken to represent the CD of the foot or toes. Repeatability of the measuring equipment was first assessed by noting the presence or absence of each corresponding capillary in 2 prints, taken at intervals of hours or days (in 10 subjects) or months (in 2 patients), of an identical area of skin which was marked by a microtattoo on the first occasion. On average, 95% of corresponding capillaries were identified in both prints (from controls and patients), thus implying little intrinsic temporal variation of capillary anatomy as well as excellent repeatability of the measuring equipment. Repeatability of data analysis was assessed by the same observer reading the same 20 prints in a blinded manner on three separate occasions (intraobserver repeatability), and 2 observers reading the same 24 prints (interobserver repeatability). The mean coefficient of intraobserver variation of CD estimate was 5.6% and the interobserver correlation coefficient was 0.94. Finally, overall repeatability of the method was assessed by repeating the procedure on a subsequent occasion (mean time interval of 5 days) in 10 subjects. The rate of agreement in mean CD between the two procedures [defined as 100- (difference between the two measurements/mean of the two measurements) x 100]% ranged from 86.4 to 97.1% (mean 93.5%). Thus using the above methodological technique, native capillaroscopy can be reliably used to determine CD of the dorsum of foot in comparing patient subgroups, as well as in longitudinal studies.

Relaxation of vascular smooth muscle induced by low-power laser radiation

The relaxation of rabbit aorta rings induced by low-power laser radiation was investigated in vitro to determine the location of the chromophore(s) responsible for this response and evaluate possible mechanisms. An action spectrum for relaxation was measured on rabbit thoracic aorta rings precontracted with norepinephrine. The decrease in isometric tension was measured during exposure to laser light (351-625 nm) delivered via a fiber optic to a small spot on the adventitial surface. The shortest UV wavelength (351 nm) was 35-fold more effective than 390 nm and 1700-fold more effective than 460 nm. Ultraviolet wavelengths also produced greater maximum relaxation (0.40-0.45) than visible wavelengths (0.20-0.25), suggesting that photovasorelaxation involves more than one chromophore. The adventitial layer was not necessary for photovasorelaxation, indicating that the light is absorbed by a chromophore in the medial layer. The same degree of relaxation was obtained on rings without adventitia when either one-half of the ring, or a small spot was irradiated indicating that communication between smooth muscle cells spreads a signal from the area illuminated to the entire ring. The mechanism for photovasorelaxation was investigated using potential inhibitors. N-monomethyl-L-arginine and N-amino-L-arginine, inhibitors of nitric oxide synthase, did not alter photovasorelaxation nor did indomethacin, an inhibitor of cyclooxygenase, and zinc protoporphyrin, an inhibitor of heme oxygenase.