The federal government's oversight of CT safety: regulatory possibilities

Cardiac CT angiography: Financial implications of different practice types

Cardiac computed tomography (CT) is an important diagnostic tool in the management of cardiovascular disease. Various factors influence the overall financial viability of a cardiac CT program, including hardware, software, personnel, billing, and practice type. This review offers a comprehensive analysis of these different cardiac CT costs, and how programs across various practice types manage them.

Trends in Inpatient Utilization of Head Computerized Tomography Scans in the United States: A Brief Cross-Sectional Study

Background

Although computed tomography (CT) has revolutionized the field of medicine due to its incredible diagnostic capabilities, the trends regarding the usage of CT scans, especially in the field of neuroscience, are not very clear. We aim to find the trends in the usage of inpatient head CT scans in the United States using a robust database. 

Methods

We queried the national inpatient usage of head CT scans in the United States from 1997 to 2014 using a robust national database. The trends in usage were analyzed based on age, gender, insurance types, and patients’ income. 

Results

During the study period, we recorded a total of 5,309,329 head CT scans, of which 51% were female. The total number of head CT scans in the United States dropped significantly from 527,026 cases to 181,095 cases (p=0.000). The decrease was with a steep slope from 1997 to 2002, and since then the decreasing slope turned to a steady state. The decrease in head CT scans was significant in all age groups (p = 0.001), more significant in uninsured payers (-79.4%, p=0.000), and prominent in low-income patients (-70.5 %, p=0.000).

Conclusions

Our study showed that national inpatient usage of CT scans of the head significantly decreased during the past two decades. This decrease is presumably multifactorial: reducing the number of unnecessary radiations, increased appropriateness audits by the government, payers’ payment reductions, and integrated electronic platforms.

X-ray cabinet to deliver highly characterized low-dose soft x-ray radiation to biological samples

We have designed, built, and tested a climate-controlled, radiation-shielded incubator cabinet for the purpose of analyzing the effects of low-dose x-ray radiation on biological tissues and cell cultures. Bremsstrahlung x rays incident on exchangeable fluorescence plates produce strong, quasi-monochromatic radiation directed toward a small container of biological samples. The x-ray source, sample, and detector are enclosed in an incubator-maintaining the optimal environment for biological samples to increase longevity to a maximum of 72 h. To demonstrate the capabilities of the setup, an example experiment is presented. Rat vascular smooth muscle cell growth was observed after irradiation with characteristic x rays of iron, copper, and calcium to impart doses of 2 mGy each. Cultures show significant spectrum dependent increases in cell number over controls at 48 h after irradiation. The experiment lends credence to the efficacy of the apparatus and shows promise for future low-dose bio-radiation studies.

Automatic Mapping of CT Scan Locations on Computational Human Phantoms for Organ Dose Estimation

To develop an algorithm to automatically map CT scan locations of patients onto computational human phantoms to provide with patient-specific organ doses. We developed an algorithm that compares a two-dimensional skeletal mask generated from patient CTs with that of a whole body computational human phantom. The algorithm selected the scan locations showing the highest Dice Similarity Coefficient (DSC) calculated between the skeletal masks of a patient and a phantom. To test the performance of the algorithm, we randomly selected five sets of neck, chest, and abdominal CT images from the National Institutes of Health Clinical Center. We first automatically mapped scan locations of the CT images on a computational human phantom using our algorithm. We had several radiologists to manually map the same CT images on the phantom and compared the results with the automated mapping. Finally, organ doses for automated and manual mapping locations were calculated by an in-house CT dose calculator and compared to each other. The visual comparison showed excellent agreement between manual and automatic mapping locations for neck, chest, and abdomen-pelvis CTs. The difference in mapping locations averaged over the start and end in the five patients was less than 1 cm for all neck, chest, and AP scans: 0.9, 0.7, and 0.9 cm for neck, chest, and AP scans, respectively. Five cases out of ten in the neck scans show zero difference between the average manual and automatic mappings. Average of absolute dose differences between manual and automatic mappings was 2.3, 2.7, and 4.0% for neck, chest, and AP scans, respectively. The automatic mapping algorithm provided accurate scan locations and organ doses compared to manual mapping. The algorithm will be useful in cases requiring patient-specific organ dose for a large number of patients such as patient dose monitoring, clinical trials, and epidemiologic studies.

Medical imaging dose optimisation from ground up: expert opinion of an international summit

As in any medical intervention, there is either a known or an anticipated benefit to the patient from undergoing a medical imaging procedure. This benefit is generally significant, as demonstrated by the manner in which medical imaging has transformed clinical medicine. At the same time, when it comes to imaging that deploys ionising radiation, there is a potential associated risk from radiation. Radiation risk has been recognised as a key liability in the practice of medical imaging, creating a motivation for radiation dose optimisation. The level of radiation dose and risk in imaging varies but is generally low. Thus, from the epidemiological perspective, this makes the estimation of the precise level of associated risk highly uncertain. However, in spite of the low magnitude and high uncertainty of this risk, its possibility cannot easily be refuted. Therefore, given the moral obligation of healthcare providers, 'first, do no harm,' there is an ethical obligation to mitigate this risk. Precisely how to achieve this goal scientifically and practically within a coherent system has been an open question. To address this need, in 2016, the International Atomic Energy Agency (IAEA) organised a summit to clarify the role of Diagnostic Reference Levels to optimise imaging dose, summarised into an initial report (Järvinen et al 2017 Journal of Medical Imaging 4 031214). Through a consensus building exercise, the summit further concluded that the imaging optimisation goal goes beyond dose alone, and should include image quality as a means to include both the benefit and the safety of the exam. The present, second report details the deliberation of the summit on imaging optimisation.

Impact of California Computed Tomography Dose Legislation: Survey of Radiologists

INTRODUCTION

Highly publicized accounts of radiation overdose from computed tomography (CT) in both children and adults prompted legislation in California regulating CT dose. The purpose of this study was to determine the impact of the law (codified in Senate Bill [SB] 1237) on California radiologist practice patterns and understanding of CT dose.

MATERIALS AND METHODS

All radiologist members of the California Radiological Society were surveyed in August-September 2013. Questions gauged radiologists' familiarity with and attitudes toward the law, awareness of CT dose, and changes in practice following the law's enactment.

RESULTS

Of 1,300 surveyed, 138 (11%) responded; 132 of 137 (96%) were familiar with SB 1237. Of 135 responding, 126 and 115 (93% and 85%, respectively) knew to report CT dose index volume and dose-length product. Sixty of 134 (45%) attributed dose reporting to an increased awareness of appropriate dose ranges. Twenty-nine of 133 (22%) had modified protocols in concert with SB 1237s enactment. Of 31 responding, 5 (16%), 23 (74%), and 3 (74%) had modified protocols in only children, both adults and children, and only adults, respectively. Twenty-four of 129 (19%) utilized automated dose reporting; 48 (37%) and 57 (44%) used dictation/transcription and template-assisted voice recognition, respectively. Forty of 134 (30%) noted delays finalizing CT reports.

CONCLUSIONS

Most radiologists who responded in our sample were familiar with SB 1237. Nearly half attributed dose reporting to an increased awareness of appropriate dose ranges. Almost one quarter indicated protocol modifications, the majority including children, occurring in conjunction with the law. Reporting inefficiency was a common concern.

Meeting the Needs for Radiation Protection: Diagnostic Imaging

Radiation and potential risk during medical imaging is one of the foremost issues for the imaging community. Because of this, there are growing demands for accountability, including appropriate use of ionizing radiation in diagnostic and image-guided procedures. Factors contributing to this include increasing use of medical imaging; increased scrutiny (from awareness to alarm) by patients/caregivers and the public over radiation risk; and mounting calls for accountability from regulatory, accrediting, healthcare coverage (e.g., Centers for Medicare and Medicaid Services), and advisory agencies and organizations as well as industry (e.g., NEMA XR-29, Standard Attributes on CT Equipment Related to Dose Optimization and Management). Current challenges include debates over uncertainty with risks with low-level radiation; lack of fully developed and targeted products for diagnostic imaging and radiation dose monitoring; lack of resources for and clarity surrounding dose monitoring programs; inconsistencies across and between practices for design, implementation and audit of dose monitoring programs; lack of interdisciplinary programs for radiation protection of patients; potential shortages in personnel for these and other consensus efforts; and training concerns as well as inconsistencies for competencies throughout medical providers' careers for radiation protection of patients. Medical care providers are currently in a purgatory between quality- and value-based imaging paradigms, a state that has yet to mature to reward this move to quality-based performance. There are also deficits in radiation expertise personnel in medicine. For example, health physics academic programs and graduates have recently declined, and medical physics residency openings are currently at a third of the number of graduates. However, leveraging solutions to the medical needs will require money and resources, beyond personnel alone. Energy and capital will need to be directed to:• innovative and cooperative cross-disciplinary institutional/practice oversight of and guidance for the use of diagnostic imaging (e.g., radiology, surgical specialties, cardiologists, and intensivists);• initiatives providing practical benchmarks (e.g., dose index registries);• comprehensive (consisting of access, integrity, metrology, analytics, informatics) and effective and efficient dose monitoring programs;• collaboration with industry;• improved use of imaging, such as through decision support combined with evidence-based appropriateness for imaging use;• integration with e-health such as medical records;• education, including information extending beyond the medical imaging community that is relevant to patients, public, and providers and administration;• identification of opportunities for alignment with salient media and advocacy organizations to deliver balanced information regarding medical radiation and risk;• open lines of communication between medical radiation experts and appropriate bodies such as the U.S. Environmental Protection Agency, the U.S. Food and Drug Administration, and the Joint Commission to assure appropriate guidance on documents and actions originating from these organizations; and• increased grant funding to foster translational work that advances understanding of low-level radiation and biological effects.

Radiologist compliance with California CT dose reporting requirements: a single-center review of pediatric chest CT

OBJECTIVE

Effective July 1, 2012, CT dose reporting became mandatory in California. We sought to assess radiologist compliance with this legislation and to determine areas for improvement.

MATERIALS AND METHODS

We retrospectively reviewed reports from all chest CT examinations performed at our institution from July 1, 2012, through June 30, 2013, for errors in documentation of volume CT dose index (CTDIvol), dose-length product (DLP), and phantom size. Reports were considered as legally compliant if both CTDIvol and DLP were documented accurately and as institutionally compliant if phantom size was also documented accurately. Additionally, we tracked reports that did not document dose in our standard format (phantom size, CTDIvol for each series, and total DLP).

RESULTS

Radiologists omitted CTDIvol, DLP, or both in nine of 664 examinations (1.4%) and inaccurately reported one or both of them in 56 of the remaining 655 examinations (8.5%). Radiologists omitted phantom size in 11 of 664 examinations (1.7%) and inaccurately documented it in 20 of the remaining 653 examinations (3.1%). Of 664 examinations, 599 (90.2%) met legal reporting requirements, and 583 (87.8%) met institutional requirements. In reporting dose, radiologists variably used less decimal precision than available, summed CTDIvol, included only series-level DLP, and specified dose information from the scout topogram or a nonchest series for combination examinations.

CONCLUSION

Our institutional processes, which primarily rely on correct human performance, do not ensure accurate dose reporting and are prone to variation in dose reporting format. In view of this finding, we are exploring higher-reliability processes, including better-defined standards and automated dose reporting systems, to improve compliance.

Initial outcomes from federally mandated accreditation site surveys of advanced diagnostic imaging facilities performed by the ACR

PURPOSE

The aim of this study was to evaluate the findings of the first year of validation site surveys performed by the ACR pursuant to new federal accreditation requirements for nonhospital advanced diagnostic imaging (ADI) facilities.

METHODS

In the first year of validation site surveys (November 2012 to November 2013), the ACR surveyed 943 ADI facilities across 21 states. Data were extracted from these site survey reports and analyzed on the basis of the survey outcomes and the frequency and type of deficiencies and recommendations. Follow-up data were obtained from the ACR for facilities deemed noncompliant on the site survey to determine if these facilities adequately took the corrective actions necessary to maintain accreditation.

RESULTS

Of the 943 ADI facilities surveyed, 45% (n = 421) were deemed compliant with the ACR accreditation standards, and 55% (n = 522) had one or more deficiencies. Failure to produce the required personnel documentation and absence of mandatory written policies were the two most common causes of deficiencies. Facilities accredited in more modalities tended to fare better in the site surveys, with the number of accredited modalities at a facility negatively associated with the likelihood of a deficiency (P = .007). Of the facilities with deficiencies, 73% (n = 382) took the necessary corrective actions to maintain accreditation, 27% (n = 140) were in the process of taking corrective actions, and no facility has lost accreditation because of an inability to adequately address the deficiencies. Nonbinding recommendations were made to 37% (n = 346) of facilities, and facilities with deficiencies were statistically more likely to receive recommendations (P < .001).

CONCLUSIONS

Initial site surveys of ADI facilities demonstrated a high proportion of deficient facilities, but no facility has lost accreditation because of an inability to correct these deficiencies. Knowledge of the most common sources of deficiencies and recommendations can assist ACR-accredited ADI facilities in better preparing for validation site surveys, reducing the likelihood of facility noncompliance.