Use of contrast media in diagnostic imaging: medico-legal considerations. Radiol Med. 2015;120:802-809. [PMID: 26082145 PMCID: PMC4545190 DOI: 10.1007/s11547-015-0549-6]

The environmental sustainability implications of contrast media supply chain disruptions during the COVID-19 pandemic: A document analysis of international practice guidelines

INTRODUCTION

Travel restrictions implemented during the acute phases of the COVID-19 pandemic disrupted supply chain for critical radiology consumables including contrast media (CM) leading to shortages. Consequently, some departments had to restructure their clinical workflows in accordance to recommended guidelines to ensure safe continuity of patient care. This study aimed to summarise the temporary crisis-driven recommendations with implicit environmental sustainability essence and to analyse how these measures might inform the development of a more sustainable, long-term clinical guideline for safer and cost-effective CM usage without compromising diagnostic quality.

METHODS

Documents were obtained through an electronic database search together with a relevant manual search in Google Scholar and relevant reference lists. The selected documents were subjected to a pre-defined eligibility criteria for inclusion. The READ approach was employed for document analysis and a thematic analysis of the obtained data was conducted.

RESULTS

Of the 17 documents included, 70% (n = 12) emanate from the United States of America. The summary of the findings relate to minimising CM usage through strategic clinical approaches including optimisation of CM volumes, prioritisation of non-contrast imaging and/or alternative imaging depending on patient need without compromising diagnostic quality.

CONCLUSION

Critical lessons of sustainability essence are implicitly embedded in the policy guidelines issued during the periods of acute CM shortage in the COVID-19 pandemic. These lessons were themed around CM conservation based on: type and priority of medical imaging investigation, kind of imaging modality and use of smaller vials over multi-dose vials packaging.

IMPLICATIONS FOR PRACTICE

The temporary crisis-driven strategies may offer critical lessons for post-pandemic service delivery to enhance patient safety while saving cost and promoting greener practice via strategic clinical and operational monitoring of CM through policy renewal, education and training and collaboration with industry partners.

Gender Differences in Pharmacokinetics: A Perspective on Contrast Agents

Gender is an important risk factor for adverse drug reactions. Women report significantly more adverse drug reactions than men. There is a growing consensus that gender differences in drug PK is a main contributor to higher drug toxicity in women. These differences stem from physiological differences (body composition, plasma protein concentrations, and liver and kidney function), drug interactions, and comorbidities. Contrast agents are widely used to enhance diagnostic performance in computed tomography and magnetic resonance imaging. Despite their broad use, these contrast agents can lead to important adverse reactions including hypersensitivity reactions, nephropathy, and hyperthyroidism. Importantly, female gender is one of the main risk factors for contrast agent toxicity. As these adverse reactions may be related to gender differences in PK, this perspective aims to describe distribution and elimination pathways of commonly used contrast agents and to critically discuss gender differences in these processes.

Exploring the implementation of role extension for Namibian radiographers: Perspectives on intravenous injection of contrast media

INTRODUCTION

Role extension to include intravenous (IV) injection of contrast media has been formally embraced by radiographers and their regulatory bodies in developed countries. The revised scope of practice, in our Namibian context, has formalised IV injection as an extended role for radiographers. This study aimed to explore the perspectives of radiographers regarding this new role of IV injection of contrast media.

METHODS

A qualitative design with a descriptive phenomenological approach was employed to collect data from 15 radiographers working in both public and private radiology facilities. Participants were purposively selected to participate in focus group discussions and individual interviews. An interview guide was used to facilitate the discussions and interviews, and a voice recorder was used for recording. Data were transcribed verbatim and analysed using Tesch's 8-step method.

RESULTS

From the 15 participants, three themes were developed: enhanced service delivery with two subthemes (improved departmental workflow and patient care), training needs with two subthemes (inadequate contrast media reaction training and standardised training requirement), and medical-legal issues with two subthemes (regulatory blurriness and role conflict distress).

CONCLUSION

The participants expressed mixed perceptions towards the IV injection role of radiographers, emphasising the benefits for the department and patients while raising concerns regarding standardisation of training and associated medico-legal issues. Furthermore, a large-scale evaluation is necessary to uncover the challenges and barriers to the successful adoption of this new role.

IMPLICATIONS FOR PRACTICE

The role extension for radiographers to include IV injections is a long-awaited development, but it should be accompanied by the necessary training and guidelines to fully realise its benefits.

Contrast Agent Administration as a Source of Liability: A Legal Database Analysis

Background Radiology ranks high in terms of specialties implicated in medical malpractice claims. While most radiologists understand the risks of liability for missed findings or lapses of communication, liability for the use of contrast agents in imaging procedures may be underappreciated. Purpose To review the clinical context and outcomes of lawsuits alleging medical malpractice for contrast-related imaging procedures. Materials and Methods Two large U.S. legal databases were queried using the terms "Contrast" and "Radiology OR Radiologist" from database inception to October 31, 2022, to identify cases with published decisions or settlements related to medical malpractice in patients who underwent contrast-related imaging procedures. The search results were screened to include only those cases involving the practice area of health care law where there was at least one claim of medical negligence against a health care institution or provider. Data on the medical complications alleged by patients after contrast agent administration and on the trial were extracted and reported using descriptive statistics. Results A total of 151 published case summaries were included in the analysis. Anaphylactic reaction following contrast agent administration was the most common medical complication observed (30% [45 of 151 cases]), of which failure to diagnose developing anaphylaxis or failure to treat the anaphylactic reaction made up the majority of allegations (93% [42 of 45]). Inappropriate management of contrast media extravasation (27% [41 of 151]) and alleged contrast agent-induced acute kidney injury (13% [19 of 151]) were the next most frequent causes of lawsuits. Of the 11 cases of alleged kidney injury that went to trial, all resulted in a judgment in favor of the defense. Conclusion This study highlights the key reasons for medical malpractice lawsuits associated with use of contrast media and outcomes from these lawsuits. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Trop in this issue.

Omniparticle Contrast Agent for Multimodal Imaging: Synthesis and Characterization in an Animal Model

PURPOSE

Individual imaging modalities have certain advantages, but each suffers from drawbacks that other modalities may overcome. The goal of this study was to create a novel contrast agent suitable for various imaging modalities that after a single administration can bridge and strengthen the collaboration between the research fields as well as enrich the information obtained from any one modality.

PROCEDURES

The contrast agent platform is based on dextran-coated iron oxide nanoparticles (for MRI and MPI) and synthesized using a modified co-precipitation method, followed by a series of conjugation steps with a fluorophore (for fluorescence and photoacoustic imaging), thyroxine (for CT imaging), and chelators for radioisotope labeling (for PET imaging). The fully conjugated agent was then tested in vitro in cell uptake, viability, and phantom studies and in vivo in a model of intraductal injection and in a tumor model.

RESULTS

The agent was synthesized, characterized, and tested in vitro where it showed the ability to produce a signal on MRI/MPI/FL/PA/CT and PET images. Studies in cells showed the expected concentration-dependent uptake of the agent without noticeable toxicity. In vivo studies demonstrated localization of the agent to the ductal tree in mice after intraductal injection with different degrees of resolution, with CT being the best for this particular application. In a model of injected labeled tumor cells, the agent produced a signal with all modalities and showed persistence in tumor cells confirmed by histology.

CONCLUSIONS

A fully functional omniparticle contrast agent was synthesized and tested in vitro and in vivo in two animal models. Results shown here point to the generation of a potent signal in all modalities tested without detrimental toxicity. Future use of this agent includes its exploration in various models of human disease including image-guided diagnostic and therapeutic applications.

Vitality markers in forensic investigations: a literature review

Determining whether an injury was sustained in life or not is one of the most important topics in forensic medicine. Morphological, cytological, and biological techniques are used to assess wound vitality. Several markers involved in vital and supravital reactions increase the accuracy of wound age estimation. This systematic review aimed to investigate the main vitality markers used in forensic medicine to date. This review was conducted by performing a systematic literature search on online resources (PubMed Central database and Google Scholar) until May 2022. We identified 46 articles published between 1987 and May 2022, analyzing a total of 53 markers. Based on the data of this review, the most studied vitality markers were adhesion molecules (fibronectin, p-selectin, CD 15), pro-inflammatory cytokines (IL-6, IL-1β, TNF-α), cathepsin D, tryptase, and microRNAs (miRNAs). The most interesting studies were based on animal models: the different markers were investigated through immunohistochemical and qRT-PCR methods. The experimental methods were usually based on skin incisions, ligature marks, and burned skin areas. To date, it has not been possible to identify any gold standard markers based on the criteria of efficacy, specificity, and reliability; however, studies are still in progress. In the future, the use of miRNAs is promising as well as the combination of multiple markers. In this way, it will be possible to increase the sensitivity and specificity to validate systems or models for determining wound vitality in forensic practice.

DyeVert Contrast Reduction System Use in Patients Undergoing Coronary and/or Peripheral Angiography: A Systematic Literature Review and Meta-Analysis

Background

Contrast-associated acute kidney injury (CA-AKI) is an important adverse effect associated with injecting iodinated intra-arterial contrast media (CM) during coronary angiography. The DyeVert™ Contrast Reduction System is a medical device intended to reduce the intra-arterial CM volume (CMV) administered. The aim of this study was to assess DyeVert System clinical effectiveness and safety by implementing a systematic review and meta-analysis of existing evidence.

Methods

Systematic electronic literature searches were conducted in MEDLINE, Embase, the Cochrane Database of Systematic Reviews, ClinicalTrials.gov, and the International Clinical Trials Registry Platform database. Relevant data were extracted from included studies and meta-analyses were performed to synthesize evidence across studies.

Results

The review included 17 eligible studies involving 1,731 DyeVert System cases and 1,387 control cases (without the use of DyeVert). Meta-analyses demonstrated use of the DyeVert System reduced CMV delivered to the patient by 39.27% (95% CI, 36.10-42.48%, P < 0.001), reduced CMV/baseline renal function ratios (Hedges's g, -0.56; 95% CI, -0.70 to -0.42, P < 0.001) and percentage of cases exceeding the maximum CMV threshold (risk difference -0.31, 95% CI, -0.48 to -0.13, P < 0.001) while maintaining adequate image quality in 98% of cases. DyeVert System cases demonstrated lower CA-AKI incidence vs. controls (absolute risk reduction 5.00% (95% CI, 0.40-9.80%; P = 0.03), relative risk 0.60 (95% CI, 0.40-0.90; P = 0.01) with a pooled estimate of the number needed to treat with the DyeVert System to avoid 1 CA-AKI event of 20.

Conclusion

DyeVert System use significantly reduces CMV delivered to the patient, CMV/baseline renal function ratios, and CA-AKI incidence while maintaining image quality. Accordingly, the device may serve as an adjunctive, procedure-based strategy to prevent CA-AKI. Future multi-center studies are needed to further assess effects of minimizing CMV on endpoints such as CA-AKI prevention, incidence of adverse cardiac and renal events, and health care costs.

Diagnostics and Therapeutics in Targeting HER2 Breast Cancer: A Novel Approach

Breast cancer is one of the most commonly occurring cancers in women globally and is the primary cause of cancer mortality in females. BC is highly heterogeneous with various phenotypic expressions. The overexpression of HER2 is responsible for 15-30% of all invasive BC and is strongly associated with malignant behaviours, poor prognosis and decline in overall survival. Molecular imaging offers advantages over conventional imaging modalities, as it provides more sensitive and specific detection of tumours, as these techniques measure the biological and physiological processes at the cellular level to visualise the disease. Early detection and diagnosis of BC is crucial to improving clinical outcomes and prognosis. While HER2-specific antibodies and nanobodies may improve the sensitivity and specificity of molecular imaging, the radioisotope conjugation process may interfere with and may compromise their binding functionalities. Aptamers are single-stranded oligonucleotides capable of targeting biomarkers with remarkable binding specificity and affinity. Aptamers can be functionalised with radioisotopes without compromising target specificity. The attachment of different radioisotopes can determine the aptamer's functionality in the treatment of HER2(+) BC. Several HER2 aptamers and investigations of them have been described and evaluated in this paper. We also provide recommendations for future studies with HER2 aptamers to target HER2(+) BC.

Harnessing amphiphilic polymeric micelles for diagnostic and therapeutic applications: Breakthroughs and bottlenecks

Amphiphilic block copolymers are widely utilized in the design of formulations owing to their unique physicochemical properties, flexible structures and functional chemistry. Amphiphilic polymeric micelles (APMs) formed from such copolymers have gained attention of the drug delivery scientists in past few decades for enhancing the bioavailability of lipophilic drugs, molecular targeting, sustained release, stimuli-responsive properties, enhanced therapeutic efficacy and reducing drug associated toxicity. Their properties including ease of surface modification, high surface area, small size, and enhanced permeation as well as retention (EPR) effect are mainly responsible for their utilization in the diagnosis and therapy of various diseases. However, some of the challenges associated with their use are premature drug release, low drug loading capacity, scale-up issues and their poor stability that need to be addressed for their wider clinical utility and commercialization. This review describes comprehensively their physicochemical properties, various methods of preparation, limitations followed by approaches employed for the development of optimized APMs, the impact of each preparation technique on the physicochemical properties of the resulting APMs as well as various biomedical applications of APMs. Based on the current scenario of their use in treatment and diagnosis of diseases, the directions in which future studies need to be carried out to explore their full potential are also discussed.

Interventional radiology in gynecology and obstetric practice: Safety issues

Interventional radiology is continuing to reshape current practice in many specialties of clinical care and the fields of gynecology and obstetrics are no exception. Imaging skills, clinical knowledge as well as vascular and non-vascular interventional technical ability, are essential to practice interventional radiology effectively. Patient safety is of paramount importance in interventional radiology as in all branches of medicine. Potential failures occur throughout successful procedures and are attributed to a spectrum of errors, including equipment unavailability, planning errors, and communication errors. These are mainly preventable by improved preprocedural planning and teamwork. Of all the targeted and effective actions that can be undertaken to reduce adverse events, the use of safety checklists might have a prominent role. The advantage of a safety checklist for interventional radiology is that it guarantees that human error in terms of forgetting key steps in patient preparation, intraprocedural care, and postoperative care are not forgotten.

Dematerialisation of patient's informed consent in radiology: insights on current status and radiologists' opinion from an Italian online survey

PURPOSE

To assess the current status of patient's informed consent (PIC) management at radiological centres and the overall opinion of radiologist active members of the Italian Society of Medical Radiology (SIRM) about PIC dematerialisation through an online survey.

METHODS AND MATERIALS

All members were invited to join the survey as an initiative by the Imaging Informatics Chapter of SIRM. The survey consisted of 11 multiple-choice questions about participants' demographics, current local modalities of PIC acquisition and storage, perceived advantages and disadvantages of PIC dematerialisation over conventional paper-based PIC, and overall opinion about PIC dematerialisation.

RESULTS

A total of 1791 radiologists (amounting to 17.4% of active SIRM members for the year 2016) joined the survey. Perceived advantages of PIC dematerialisation were easier and faster PIC recovery (96.5%), safer storage and conservation (94.5%), and reduced costs (90.7%). Conversely, the need to create dedicated areas for PIC acquisition inside each radiological unit (64.0%) and to gain preliminary approval for the use of advanced digital signature tools from patients (51.8%) were seen as potential disadvantages. Overall, 94.5% of respondents had a positive opinion about PIC dematerialisation.

CONCLUSION

Radiologists were mostly favourable to PIC dematerialisation. However, concerns were raised that its practical implementation might face hurdles due to its complexity in current real life working conditions.

Radiographic and magnetic resonances contrast agents: Essentials and tips for safe practices

With extended and continued expansion of medical imaging utilization in modern medical practice over last decade, radiologists as well as other faculty staff dealing with radiographic and magnetic resonances contrast media (CM) have to be well oriented with their potential hypersensitivity reactions and recognize high-risk groups liable to develop it and enable early recognition. Radiologists and other medical staff involved in administration and dealing with CM have to be ready to implement prompt, practical and effective management plan to deal with these scenarios should they emerge. Strategies to prevent potential contrast-induced acute and delayed renal injuries have to be routinely exercised. Paying attention to the pregnant and nursing women, pediatrics, diabetics, as well as other fragile populations is of utmost importance for patient safety during contrast administrations. Radiologists should play a pivotal role in orienting patients about necessity to use CM for their imaging studies, in case it is needed, and assure them about its safety. Moreover, they have to be oriented with the medico-legal issues related to use of CM. These will pay as improved patient safety as well as safe daily working environmentat different levels of radiology practices.

Systemic Error in Radiology

OBJECTIVE

Interpretive errors in diagnostic imaging result in significant patient morbidity and mortality, but the importance of errors and process failures in the imaging cycle other than during image interpretation is underappreciated. In this article, we describe these errors and potential solutions, providing a framework to improve patient safety and understand the changing roles of radiologists beyond image interpretation.

CONCLUSION

For comprehensive improvements to health care delivery, other failures in the cycle besides diagnostic interpretive error-such as ordering inappropriate studies, PACS failures, and a lack of accurate clinician contact information (with resultant communication failure)-should be recognized as contributors to patient harm because they lead to wasted resources and delayed care. By taking ownership of the entire imaging cycle, radiologists can increase their net worth to patient care and cement their roles as experts in the effective, evidence-based use of imaging technologies.

Autonomy, consent and responsibility. Part II. Informed consent in medical care and in the law

Legal recognition of patient's rights aspired to change clinical relationship and medical lex artis. However, its implementation has been hampered by the scarcity of resources and the abundance of regulations. For several years, autonomy, consent, and responsibility have formed one of the backbones of the medical profession. However, they have sparked controversy and professional discomfort. In the first part of this article, we examine the conceptual and regulatory limitations of the principle of autonomy as the basis of informed consent. We approach the subject from philosophical, historical, legal, bioethical, deontological, and professional standpoints. In the second part, we cover the viability of informed consent in health care and its relationship with legal responsibility.

Morphometric analysis of stab wounds by MSCT and MRI after the instillation of contrast medium

OBJECTIVE

To analyze the morphology and depth of stab wounds experimentally produced on human legs amputated for medical reasons using multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) after the instillation of a single contrast medium solution (CMS).

MATERIALS AND METHODS

For morphological analysis, MSCT and MRI scans were performed before and after the instillation of CMS into the wound cavity. Depth measurements were performed on the sagittal view only after CMS instillation. Subsequently, each wound was dissected using the layer-by-layer technique and the depth was measured by a ruler. One-way between-groups pairwise analysis of variance (ANOVA) and Bland-Altman plot analysis were used for comparing radiological and anatomical measurements.

RESULTS

Unenhanced MSCT images did not identify the wound channels, whereas unenhanced MRI evidenced the wound cavity in 50 % of cases. After the instillation of CMS, both MSCT and MRI depicted the wound channel in all the investigated stabbings, although the morphology of the cavity was irregular and did not resemble the shape of the blade. The radiological measurements of the wounds' depth, after the application of CMS, exhibited a high level of agreement (about 95 % at Bland-Altman plot analysis) with the anatomical measurements at dissection. A similar systematic underestimation, however, has been evidenced for MSCT (average 11.4 %; 95 % CI 7-17) and MRI (average 9.6 %; 95 % CI 6-13) data after the instillation of CMS with respect to wound dissection measurements.

CONCLUSION

MSCT and MRI after the instillation of CMS can be used for depicting the morphometric features of stab wounds, although depth measurements are affected by a slight systematic underestimation compared to layer-by-layer dissection.