Radiation Exposure to Staff in Intensive Care Unit with Portable CT Scanner.

Background. Bedside radiological procedures pose a risk of radiation exposure to ICU staff. The perception of risk may increase the degree of caution among the health care staff and raise new barriers preventing patients from obtaining prompt care. Objective. The aim of this study was to estimate the annual cumulative radiation dose to individual ICU staff. Methods. In this prospective study, forty subjects were required to wear thermoluminescent dosimeter badges during their working hours. The badges were analyzed to determine the exposure after 3 months. Results. A total of 802 radiological procedures were completed at bedside during the study period. The estimated annual dosage to doctors and nurses on average was 0.99 mSv and 0.88 mSv (p < 0.001), respectively. Residents were subjected to the highest radiation exposure (1.04 mSv per year, p = 0.002). The radiation dose was correlated with day shift working hours (r = 0.426; p = 0.006) and length of service (r = -0.403; p < 0.01). Conclusions. With standard precautions, bedside radiological procedures-including portable CT scans-do not expose ICU staff to high dose of ionizing radiation. The level of radiation exposure is related to the daytime working hours and length of service.

Orbitectomía en monobloque en un paciente con sarcoma neurogénico de la órbita / Single block orbitectomy in a patient with neurogenic orbital sarcoma

El sarcoma neurogénico es un tumor maligno que se origina en las células de Schwann de la vaina del revestimiento de los nervios periféricos y son poco frecuentes en la órbita. Se presenta un paciente de 23 años de edad, masculino, blanco, con antecedentes de neurofibromatosis tipo I, con desplazamiento anteroinferior del globo ocular izquierdo, dolor intenso y pérdida de la visión de 4 meses de evolución. Al examen oftalmológico se constató proptosis severa con descenso del globo ocular izquierdo, oftalmoplejia total, quemosis severa, hiperemia, opacidad corneal y aumento de volumen del párpado superior. En los estudios imagenológicos se evidenció lesión tumoral que ocupaba la totalidad del compartimiento orbitario sin infiltración de sus paredes óseas y con desplazamiento del globo ocular por fuera del reborde orbitario. Se realizó un abordaje quirúrgico combinado, y se logró una orbitectomía en monobloque con resección total del tumor y reconstrucción con colgajo rotado de músculo temporal ipsilateral. El estudio histopatológico informó la presencia de un sarcoma neurogénico de la órbita y se complementó con tratamiento adyuvante con radioterapia. El paciente se mantuvo controlado durante un año y a partir de esta fecha comenzó la aparición secuencial de varias lesiones a distancia(AU)

Neurogenic sarcoma is a malignant tumor that starts in Schwann cells of the peripheral nerves sheath and is rarely found in the orbit. Here is a 23 year old, male, Caucasian patient, with a history of Type-I Neurofibromatosis, and a left eye fore and lower side displacement of the left eyeball, intense pain and loss of vision for 4 months. A severe proptosis and the lowering of the left eyeball was detected during the ophthalmologic examination, as well as total ophthalmoplegia, severe chemosis, hyperemia, corneal opacity and increased upper eyelid volume. Imaging studies revealed a tumor lesion occupying the whole orbital compartment, with no bone wall infiltration, but causing the displacement of the eyeball out of the orbit border. A combined surgical approach was performed consisting in a single block orbitectomy with total tumor resection, as well as the reconstruction with the ipsilateral temporal muscle rotated flap. The histopathology study showed the presence of an neurogenic orbital sarcoma, so an adjuvant radiotherapy treatment was indicated. The patient was followed up for a year, after which the sequential occurrence of several lesions began(AU)

Taxanes as a risk factor for acute adverse reactions to iodinated contrast media in cancer patients.

BACKGROUND: The impact of cytotoxic agents on the risk of acute allergy-like adverse reactions (ARs) to intravenous iodinated contrast media (ICM) injections is unknown. METHODS: We retrospectively reviewed 13,565 computed tomography (CT) scans performed in a consecutive cohort of cancer patients from January 1, 2010 to December 31, 2012. Episodes of acute ICM-related ARs were reported to the pharmacovigilance officer. The following matched comparisons were made: tax code, gender, primary tumor, antineoplastic therapy, and date of last cycle. Concomitant antineoplastic treatment was classified into five groups: platinum, taxane, platinum plus taxane, other, and no treatment group (no therapy had been administered in the previous 24 months). Logistic regression was used to estimate odds ratio (OR) and 95% confidence interval (CI) to evaluate the risk of acute ICM-related ARs. RESULTS: Of 10,472 contrast-enhanced CT scans, 97 (0.93%; 95% CI: 0.74-1.11) ICM-related ARs were reported, 11 of which (0.1%) were severe, including one fatality. The overall incidence was significantly higher in patients aged <65 years (p = .0062) and in the platinum plus taxane and taxane groups (p = .007), whereas no correlation was found with gender, number of previous CT scans, site of disease, or treatment setting. Multivariate analysis confirmed an increased risk for patients aged <65 years (OR: 1.73; 95% CI: 1.14-2.63) and for the taxane group (in comparison with the no treatment group; OR: 2.06; 95% CI: 1.02-4.16). CONCLUSION: Among cancer patients, concomitant treatment with taxanes and younger age would seem to be risk factors for ICM-related ARs.

Radiation exposure and air travel: should we worry?

With the federal government introducing new advanced imaging scanners at airports, the traveling public has become concerned about the radiation exposure they may receive when passing through scanners as well as during flight. This article offers a primer on radiation and the extent to which exposure from various sources can affect health. It also provides advice for physicians whose patients may have concerns about radiation exposure during air travel.

Commentary: for the children's sake, avoid non-contrast CT.

Enough literature now exists such that doing a non-contrast abdominal or chest computed tomography (CT) scan for suspected mass lesions in children borders on malpractice. Although there is great uncertainty regarding estimated radiation doses and long-term cancer risks in childhood, there is no doubt that an entirely unnecessary CT study does more harm than good. When a chest or abdominal mass is suspected in a child, only a post-intravenous contrast enhanced CT examination is needed, and a prior non-enhanced CT run exposes the child to unnecessary radiation.

X-ray radiation causes electromagnetic interference in implantable cardiac pacemakers.

BACKGROUND: X-rays are not thought to cause electromagnetic interference (EMI) in implantable cardiac pacemakers. However, x-ray radiation during computed tomography (CT) scanning has been reported to cause EMI in some implantable cardiac pacemakers. The objectives of this study were to identify the location within the pacemakers where x-ray radiation causes EMI and to investigate the association of EMI with the x-ray radiation conditions. METHODS: We verified the location where x-ray radiation caused EMI using a CT scanner and conventional radiographic x-ray equipment. An inhibition test and an asynchronous test were performed using five types of implantable cardiac pacemakers. RESULTS: X-ray radiation inhibited the pacing pulses of four types of implantable cardiac pacemakers when the body of each implantable cardiac pacemaker, containing a complementary metal-oxide semiconductor (CMOS), was scanned using a CT scanner. We confirmed that x-ray-induced EMI depends on the x-ray radiation conditions, that is, the tube voltage, tube current, x-ray dose, and direction of x-ray radiation, as well as the sensing thresholds of the implantable cardiac pacemakers. CONCLUSIONS: X-ray radiation caused EMI in some implantable cardiac pacemakers, probably because the CMOS component was irradiated. The occurrence of EMI depended on the pacemaker model, sensing threshold of the pacemaker, and x-ray radiation conditions.

Carotid atheroma rupture observed in vivo and FSI-predicted stress distribution based on pre-rupture imaging.

Atherosclerosis at the carotid bifurcation is a major risk factor for stroke. As mechanical forces may impact lesion stability, finite element studies have been conducted on models of diseased vessels to elucidate the effects of lesion characteristics on the stresses within plaque materials. It is hoped that patient-specific biomechanical analyses may serve clinically to assess the rupture potential for any particular lesion, allowing better stratification of patients into the most appropriate treatments. Due to a sparsity of in vivo plaque rupture data, the relationship between various mechanical descriptors such as stresses or strains and rupture vulnerability is incompletely known, and the patient-specific utility of biomechanical analyses is unclear. In this article, we present a comparison between carotid atheroma rupture observed in vivo and the plaque stress distribution from fluid-structure interaction analysis based on pre-rupture medical imaging. The effects of image resolution are explored and the calculated stress fields are shown to vary by as much as 50% with sub-pixel geometric uncertainty. Within these bounds, we find a region of pronounced elevation in stress within the fibrous plaque layer of the lesion with a location and extent corresponding to that of the observed site of plaque rupture.

[Total body CT scan as the primary diagnostic modality in multi-trauma patients]. / Primaire totale lichaams-CT bij multitraumapatiënten.

Radiological imaging is highly protocolized during initial assessment of severely injured trauma patients. After an initial examination, radiography and ultrasound are performed. Imaging is frequently supplemented by CT scan of selective body areas. Technical features of CT scanners have improved drastically and the number of CT scanners located near or in trauma resuscitation rooms is increasing. These developments enable early CT scanning in trauma patients. Currently there is an ongoing discussion as to whether 'total body' CT scan (TBCT) should be used as a primary and sole diagnostic imaging tool during workup of trauma patients. Recent research on TBCT in multi-trauma patients shows promising results and several large European trauma centers have already protocolized this strategy. These studies lack a good study design, so more prospective research on clinical outcomes, cost effectiveness and radiation exposure is necessary. As part of a pilot study in preparation for a randomized multicenter study, the University Medical Centre in Amsterdam in the Netherlands is performing TBCT in severely injured trauma patients.

Levantamento e análise de eventos adversos com aparelhos de tomografia computadorizada / Survey and analysis of adverse events with equipment for computed tomography

O estudo teve como objetivo levantar os eventos adversos relacionados ao uso doaparelho de tomografia computadorizada reportados nos sistemas de notificação doBrasil e no exterior. Classificando-os de acordo com as suas causas segundo o modelo de abordagem de Shepherd e verificando a sua correspondência com os aparelhos de tomografia computadorizada instalados no Brasil. No Brasil consultou-se o SistemaNacional de Notificação de Eventos Adversos e Queixas Técnicas desenvolvido pela Agência Nacional de Vigilância Sanitária e no exterior pesquisou-se o Medical DeviceReporting Database e o Manufacturer and User Facility Device Experience Database, ambos desenvolvidos pela Food and Drug Administration. Os eventos adversos foram classificados segundo a proporção de ocorrência por componente e por subcomponente.Levantou-se 519 eventos adversos relacionados ao aparelho de tomografia no período de 01/01/1984 a 31/12/2007, sendo que 233 relatos do MDR e 286 relatos do MAUDE. Nenhum evento foi levantado por meio do banco de dados brasileiro. O estudo mostrouque 78,2 por cento dos eventos adversos se relacionavam com o componente dispositivo médico sendo que 38,9 por cento se relacionavam ao subcomponente projeto dos circuitos e partes. O estudo mostrou também que 64,5 por cento dos eventos adversos foram classificados como mau funcionamento. O estudo classificou os eventos adversos por tipo de falha, sendo o erro de software o tipo de falha com maior ocorrência (20,7 por cento). Ao verificar a correspondência dos eventos encontrados nos bancos de notificação do exterior relacionando com os aparelhos similares existentes no Brasil, encontrou-se 356 eventos.

Cumulative diagnostic radiation exposure in children with ventriculoperitoneal shunts: a review.

INTRODUCTION: Children may be more vulnerable to diagnostic radiation exposure because of the increased dose-volume ratio and the increased lifetime risk per unit dose of radiation from early exposure. Moreover, recent radiological literature suggests that exposure to ionizing radiation from imaging studies may play a role in the later development of malignancies. MATERIALS AND METHODS: We review the literature and present two illustrative clinical examples of children (each child developed head and neck malignancies during their late teen years) with hydrocephalus requiring multiple cerebrospinal fluid (CSF) shunt revisions and diagnostic computerized tomography (CT) scans throughout their life. DISCUSSION: The literature reviewed suggests that children are more prone to diagnostic radiation exposure. Although it is not possible to prove that the multiple diagnostic studies result in malignancies, our review of the literature and illustrative cases describing malignancy risk and radiation exposure should give clinicians pause when considering requesting multiple diagnostic CT studies in children during the evaluation of possible CSF shunt dysfunction. Alternative tests such as "shunt MRI" protocols should be considered for patients and used whenever possible to minimize exposure to ionizing radiation.

Multidetector row computed tomography for follow-up of patients with coronary artery aneurysms due to Kawasaki disease.

Multidetector row computed tomography (MDCT) coronary angiography was performed using a 16-slice MDCT scanner in three children with coronary aneurysms due to Kawasaki disease. Patients were given a beta-blocker. Following contrast injection, all data were acquired during a 20-second breathhold. Results were compared with those of conventional coronary angiography performed previously. MDCT provided clear visualization of coronary artery aneurysms, with coronary calcifications but which had not yet progressed to stenotic lesions. Because MDCT allows noninvasive detection and exclusion of coronary obstructions, it may be able to replace repeat conventional angiography as a follow-up study for children with coronary artery disease.