Safety of the effective radiation dose received during stroke hospitalization / Segurança da dose de radiação efetiva recebida durante internação por acidente vascular cerebral

Abstract Background Neuroimaging is widely used for diagnosis and treatment of stroke. However, little is known about whether the radiation doses received by patients comply with international safety guidelines. Objectives The aim of this study was to evaluate the effective radiation dose received while in hospital for stroke and analyze its safety according to current guidelines. Methods This cross-sectional study included 109 patients who were hospitalized and diagnosed with ischemic stroke. The National Institutes of Health Stroke Scale was used to evaluate stroke severity, the Bamford clinical classification was used for topography, and the TOAST classification was used for etiology. The computed tomography dose index and size-specific dose estimates were used to calculate the effective radiation dose (ERD) received while in hospital. A Mann-Whitney test was used to compare the ERD received by thrombolysed and non-thrombolysed patients. Non-parametric statistics were used to analyze the data with a 95% confidence interval. Results During the study period, the median ERD received was 10.9 mSv. Length of stay was not associated with radiation exposure. No differences were demonstrated in ERD according to stroke etiology or Bamford clinical classification. Patients who had CT perfusion (only or in addition to CT or angiotomography) received the highest ERD (46.5 mSv) and the difference compared to those who did not (10.8 mSv) was statistically significant (p<0.001). No differences were found in the ERD between thrombolysed and non-thrombolysed patients. There was no correlation between ERD while in hospital and stroke severity. Conclusions According to the current national guidelines, the protocol for examining images at our stroke unit is safe in terms of the ERD received by the patient while in hospital. There was no difference in the ERD received by patients stratified by thrombolytic treatment or stroke severity.

Resumo Contexto A neuroimagem é amplamente utilizada para o diagnóstico e tratamento do acidente vascular cerebral (AVC). No entanto, pouco se sabe se a dose de radiação recebida nesses exames está de acordo com as diretrizes internacionais de segurança. Objetivos O objetivo deste estudo foi avaliar a dose de radiação efetiva (DRE) durante a hospitalização por AVC. Métodos Trata-se de estudo transversal com 109 pacientes hospitalizados com diagnóstico de AVC isquêmico. A gravidade do AVC foi avaliada pela National Institutes of Health Stroke Scale, a topografia pela classificação clínica de Bamford e a etiologia pelo Trial of ORG 10172 in Acute Stroke Treatment (TOAST). O índice de dose recebida no exame de tomografia computadorizada (TC) e as estimativas de dose específicas foram usados ​​para calcular a DRE recebida durante a hospitalização. O teste de Mann-Whitney foi utilizado para comparar a DRE recebida por pacientes trombolisados ​​e não trombolisados. Estatísticas não paramétricas foram utilizadas para analisar os dados. Resultados Durante o período do estudo, a DRE foi de 10,9 mSv. O tempo de internação não foi associado à exposição à radiação. Nenhuma diferença foi demonstrada na DRE de acordo com a etiologia e classificação clínica de Bamford. Os pacientes que fizeram perfusão (isolada, associada à TC ou angiotomografia) receberam a maior DRE (46,5 mSv) em comparação aos que não fizeram (10,8 mSv), sendo estatisticamente significativo (p <0,001). Não foram encontradas diferenças na DRE entre pacientes trombolisados e não trombolisados. Não houve correlação entre a DRE durante a hospitalização com a gravidade do AVC. Conclusões De acordo com as atuais diretrizes nacionais, o protocolo de exame de imagens na unidade de AVC é seguro em relação à DRE recebido pelo paciente durante a internação. Não houve diferença na DRE dos pacientes de acordo com o tratamento trombolítico e a gravidade do AVC.

Avaliação dos níveis de creatinina em pacientes submetidos à tomografia contrastada: uma metanálise / Creatinine level variation in patients subjected to contrast-enhanced tomography: a meta-analysis

Resumo A variação do valor encontrado nos exames de creatinina em pacientes submetidos à tomografia computadorizada (TC) contrastada tem sido utilizada como método prático para a avaliação de possíveis lesões renais causadas pelo uso do contraste. Entre os critérios, considera-se o aumento absoluto de creatinina sérica ≥ 0,5 mg/dL ou relativo em ≥ 25% para possíveis distúrbios renais, como a nefropatia induzida por contraste (NIC). Nosso objetivo foi analisar a incidência de NIC através de uma metanálise envolvendo nove artigos relacionados à incidência de lesão renal por contraste, sendo calculado o odds ratio (OR) e o intervalo de confiança (IC95%) por meio do programa RStudio. A incidência de NIC em pacientes submetidos a TC foi de 11,29%, sendo o OR de 1,38 (IC95% 0,88-2,16). Contrastes não iônicos apresentam maior segurança em seu uso que outros tipos de contraste, e o volume maior que 115 mL pode estar relacionado a NIC. A doença renal prévia apresentou significado estatístico em agravar a NIC.

Abstract Variation in the creatinine levels of patients who have undergone contrast-enhanced computed tomography (CT) has been adopted as a practical method for assessment of possible kidney damage caused by the contrast. Criteria employed include an absolute increase in serum creatinine ≥ 0.5 mg/dL or a relative increase ≥ 25% as indicative of possible renal disorders, such as contrast-induced nephropathy (CIN). Our objective was to analyze the incidence of CIN by means of a meta-analysis of nine articles related to incidence of kidney damage caused by contrast, calculating odds ratios (OR) and confidence intervals (95%CI) using RStudio. The overall incidence of CIN in patients who had CT scans was 11.29%, with an OR of 1.38 (95%CI 0.88-2.16). Non-ionic contrasts are safer than other types of contrast, and volumes exceeding 115 mL may be associated with CIN. Preexisting kidney disease had a statistically significant relationship with worse CIN rates.

Niveles de referencia para diagnóstico: una herramienta efectiva para la protección radiológica de pacientes / Diagnostic reference levels: an effective tool to radiological protection of patient

Se sabe que las exposiciones médicas con radiaciones ionizantes son actualmente la principal fuente de exposición a la radiación artificial a nivel global. Para prevenir dosis innecesariamente altas durante estas exposiciones a los pacientes, la Comisión Internacional de Protección Radiológica (ICRP) recomienda la utilización de los Niveles de Referencia para Diagnóstico (DRLs), como una herramienta efectiva de ayuda a la optimización de la protección radiológica en la exposición médica de pacientes para diagnóstico y procedimientos de intervención. Dado que la legislación chilena no tiene incorporado aún su uso, el presente trabajo de revisión tiene como objetivo, elaborar un documento guía para los profesionales de la salud y áreas afines, que contenga de manera sucinta y con recomendaciones prácticas, los principales aspectos a tener en cuenta para establecer los DRLs en procedimientos de radiodiagnóstico, intervencionismo y medicina nuclear, basados esencialmente en la publicación N° 135 de la ICRP sobre DRLs.

It is known that medical exposition with ionizing radiation is currently the main exposition source to artificial radiation at global level. To prevent unnecessarily high doses during these patient expositions, the International Commission on Radiological Protection (ICRP) recommends the use of Diagnostic Reference Levels (DRLs), as an effective tool to support the optimization of radiological protection for patient medical exposure for diagnosis and interventional procedures. Since that the Chilean legislation does not have its use incorporated yet, the present revision work aims to elaborate a guiding document for health professionals and related fields, that succinctly and with practical recommendations, the main aspects to consider for establishing DRLs in procedures for radiodiagnostic, intervention, and nuclear medicine, mainly based in N° 135 ICRP publication about DRLs.

Risco de insuficiência renal aguda pós-contraste em tomografia computadorizada: estamos atentos à função renal? / Risk of post-contrast acute kidney injury in computed tomography: are we aware of renal function?

Introdução: Exames diagnósticos contrastados oferecem riscos para o desenvolvimento de Insuficiência Renal Aguda pós-contraste (IRA-PC), principalmente em pacientes com doença renal prévia. O objetivo deste estudo foi verificar se a função renal foi avaliada antes e após a realização de exame contrastado. Métodos: Coorte retrospectiva com 2778 pacientes que realizaram tomografia computadorizada (TC) contrastada em que foi verificada a creatinina sérica (CrS) pré e pós-exame, presença de fatores de risco, incidência de IRA-PC e óbito até 10 meses pós-TC. Resultados: Somente 263 (9,5%) apresentaram avaliação da função renal pré e pós-exame dentro dos prazos estabelecidos (7 dias para pacientes internados e 180 dias para ambulatoriais pré-exame, e 48 a 72 horas pós-exame), sendo que 91,6% eram de pacientes internados. IRA-PC foi observada em 38 (14,4%) pacientes e foi associada ao uso de medicamentos nefrotóxicos (Odds Ratio 1,645; IC95%: 1,138­2,390) e maior risco de óbito pós-exame (Razão de Incidência 1,84; IC95%:1,17-2,83). Conclusão: A grande maioria dos pacientes não apresentava adequada avaliação da função renal pré e pós-TC, principalmente em nível ambulatorial. Sugere-se o estabelecimento de medidas educativas para promover a aderência do corpo clínico à avaliação da função renal para pacientes de risco para IRA-PC. (AU)

Introduction: Contrast-enhanced diagnostic tests involve risks for the development of post-contrast acute kidney injury (PC-AKI), especially in patients with previous renal disease. The aim of this study was to investigate whether renal function was evaluated before and after the contrast-enhanced test. Methods: In this retrospective cohort of 2778 patients who underwent contrast-enhanced computed tomography (CT), pre- and post-CT serum creatinine (SCr), presence of risk factors, incidence of PC-AKI, and death within 10 months post-CT were investigated. Results: Only 263 (9.5%) patients had pre- and post-CT renal function evaluation performed within the established time frames (7 days for inpatients and 180 days for outpatients pre-CT and 48 to 72 hours post-CT), with 91.6% being inpatients. PC-AKI was observed in 38 (14.4%) patients and was associated with use of nephrotoxic drugs (odds ratio: 1.645, 95% CI: 1.138-2.390) and higher risk of death post-CT (incidence ratio: 1.84; 95% CI: 1.17-2.83). Conclusion: The vast majority of patients did not undergo an adequate pre- and post-CT renal function evaluation, especially at the outpatient level. Educational measures should be developed to promote adherence of clinical staff to renal function evaluation for patients at risk for PC-AKI. (AU)

Pediatric minor head trauma: do cranial CT scans change the therapeutic approach?

OBJECTIVES: 1) To verify clinical signs correlated with appropriate cranial computed tomography scan indications and changes in the therapeutic approach in pediatric minor head trauma scenarios. 2) To estimate the radiation exposure of computed tomography scans with low dose protocols in the context of trauma and the additional associated risk. METHODS: Investigators reviewed the medical records of all children with minor head trauma, which was defined as a Glasgow coma scale ≥13 at the time of admission to the emergency room, who underwent computed tomography scans during the years of 2013 and 2014. A change in the therapeutic approach was defined as a neurosurgical intervention performed within 30 days, hospitalization, >12 hours of observation, or neuro-specialist evaluation. RESULTS: Of the 1006 children evaluated, 101 showed some abnormality on head computed tomography scans, including 49 who were hospitalized, 16 who remained under observation and 36 who were dismissed. No patient underwent neurosurgery. No statistically significant relationship was observed between patient age, time between trauma and admission, or signs/symptoms related to trauma and abnormal imaging results. A statistically significant relationship between abnormal image results and a fall higher than 1.0 meter was observed (p=0.044). The mean effective dose was 2.0 mSv (0.1 to 6.8 mSv), corresponding to an estimated additional cancer risk of 0.05%. CONCLUSION: A computed tomography scan after minor head injury in pediatric patients did not show clinically relevant abnormalities that could lead to neurosurgical indications. Patients who fell more than 1.0 m were more likely to have changes in imaging tests, although these changes did not require neurosurgical intervention; therefore, the use of computed tomography scans may be questioned in this group. The results support the trend of more careful indications for cranial computed tomography scans for children with minor head trauma.

Análise da correlação entre índices radiomorfométricos de densidade óssea, perfil de qualidade óssea em software de implante, quociente de estabilidade e torque de inserção em implantes / Analyses of the correlation among radiomorphometric indices of bone density, bone quality profile using a software implant, stability quotient, and insertion torque implants

A qualidade óssea, bem como a estabilidade inicial dos implantes, está diretamente relacionada com o sucesso das reabilitações na implantodontia. O presente estudo teve como objetivo analisar a correlação entre índices radiomorfométricos de densidade óssea por meio de radiografias panorâmicas, perfil de qualidade óssea com o auxílio de Tomografia Computadorizada de Feixe Cônico (TCFC) com o uso do software de imagens OsiriX, Análise da Frequência de Ressonância (RFA) e Torque de Inserção do implante. Foram avaliados 160 implantes de 72 indivíduos, com média etária de 55,5 (±10,5) anos. Nas radiografias panorâmicas foram obtidos os índices IM, IPM e ICM, e nas tomografias computadorizadas de feixe cônico, os valores de pixels e a espessura da cortical da crista óssea alveolar, além da estabilidade primária por meio do torque de inserção e análise da frequência de ressonância. Os resultados foram analisados pelo coeficiente de correlação de Spearman, para p<= 0,01 foi obtido entre o torque de inserção e valores de pixels (0.330), o torque de inserção e a espessura da cortical da crista alveolar (0.339), o torque de inserção e o ISQ vestibulo-lingual (0.193), os valores de pixels e espessura da cortical da crista alveolar (0.377), as duas direções vestíbulo-lingual e mesio-distal do ISQ (0.674), o ISQ vestíbulo-lingual e a espessura da cortical da crista alveolar (0.270); os índices radiomorfométricos foram correlacionados entre eles e para p<= 0,05 foi obtido entre torque de inserção e ISQ mesio-distal (0.131), entre o ISQ vestibulo-lingual e os valores de pixels (0.156) e ISQ mesio-distal e IPMI esquerdo (0.149) e ISQ mesio-distal e IPMS esquerdo (0.145). Existe correlação entre a TCFC, o torque de inserção e a RFA na avaliação da qualidade óssea. É possível utilizar, pré-cirurgicamente, os exames de TCFC para avaliar a qualidade e quantidade óssea, tendo em vista as correlações obtidas neste estudo.

The bone quality and initial stability of implants are directly related to the success of rehabilitation in implantology. The aim of this study was to analyze the correlation between radiomorphometric indexes of bone density through panoramic radiographic images, bone quality profile using the Cone-Beam Computed Tomography (CBCT) and the OsiriX imaging software, Resonance Frequency Analysis (RFA) and insertion torque implant. One hundred and sixty implants were evaluated in 72 individuals with a mean age of 55.5 (± 10.5) years. In the panoramic radiographic images, the IM, IPM and ICM indexes were assessed. For the cone beam computed tomography, the analyses included pixel values, thickness of cortical bone crest, as well as the primary stability through the insertion torque and resonance frequency. The results were analyzed by Spearman correlation coefficient for p <= 0.01. The values between insertion torque and pixel were (0.330), the insertion torque and cortical thickness of the alveolar crest were (0.339), for torque insertion and ISQ vestibule-lingual (0.193), and for pixel values and cortical thickness of the alveolar crest (0.377). Considering both directions bucco-lingual and mesial-distal ISQ the values were (0.674), the bucco-lingual ISQ and cortical thickness of the alveolar ridge were (0.270); the radiomorphometric indexes were correlated between themselves. Values of p <= 0.05 were obtained between insertion torque and mesio-distal ISQ (0.131), as well as the ISQ vestibule-lingual and the pixel values (0.156) and also mesial-distal ISQ and left IPMI (0.149) and mesial-distal ISQ and left IPMS (0.145). There is a correlation between the CBCT, the insertion torque and RFA in the evaluation of bone quality. CBCT scans can be used prior to surgery, in order to assess bone quality and quantity, considering the correlations obtained in this study.

Riesgos de la radiación en imágenes pediátricas / Radiation risks in pediatric images

The advance of medical imaging technology has led to an increase in the medical radiation exposure, especially derived from computed tomography (CT). Recent studies confirm a small but significant increase of cancer cases induced by CT radiation. Children are markedly more sensitive to radiation than adults and in addition, their life expectancy is longer, so we must use all resources to optimize and reduce the exposure dose using the ALARA concept. CT is an important diagnostic tool in medical practice and its benefits far outweigh the costs of radiation if the indication is properly justified.

El avance tecnológico de las imágenes para evaluación de enfermedades ha llevado a un aumento considerable de la radiación de origen médica, principalmente la proveniente de la tomografía computada (TC). Estudios recientes confirman un pequeño pero significativo incremento de casos de cáncer inducidos por radiación generada por la TC. Siendo los niños reconocidamente más sensibles a la radiación que los adultos y sumado a su mayor expectativa de vida, es que debemos usar todos los recursos para optimizar y reducir la dosis de exposición aplicando el concepto de ALARA. La TC es una herramienta diagnóstica importantísima en la práctica médica, y sus beneficios superan ampliamente los costos de la radiación si su indicación está adecuadamente justificada.

Extravasación de medios de contraste intravenosos: lo que todo radiólogo debe saber / Extravasation of intravenous contrast media: what every radiologist should know

The accidental release of intravenous contrast media (ICM) from the intravascular compartment to the adjacent soft tissues is one of the most frequent complications of the injection procedure in multi-slice CT (MSCT). Its incidence is low, occurring in between 0.1 and 0.9 percent of patients undergoing these studies. Affected areas usually present mild lesions characterized by swelling and local erythema and that tend to resolve spontaneously without sequelae. However, serious lesions may also occur, such as compartment syndrome. For these reasons it is essential to know patients at risk, precautionary measures, specific technical factors, early diagnosis and appropriate management of this complication. These elements constitute basic skills that every radiologist must possess.

La salida accidental de medio de contraste intravenoso (MCI) desde el compartimento intravascular hacia los tejidos de partes blandas adyacentes es una de las complicaciones más frecuentes del procedimiento de inyección en tomografía computada multicorte (TCMC). Su incidencia es baja, ocurre entre el 0,1 y el 0,9 porciento de los pacientes que se someten a estos estudios. Las zonas afectadas generalmente presentan lesiones leves caracterizadas por aumento de volumen y eritema local que tienden a remitir espontáneamente sin secuelas. Sin embargo, también pueden ocurrir lesiones graves, como un síndrome compartimental. Por estas razones es fundamental conocer los pacientes en riesgo, las medidas de precaución, los factores técnicos específicos, el diagnóstico precoz y el manejo oportuno de esta complicación. Estos elementos constituyen competencias básicas que todo radiólogo debe poseer.

Lung Infarction due to Pulmonary Vein Stenosis after Ablation Therapy for Atrial Fibrillation Misdiagnosed as Organizing Pneumonia: Sequential Changes on CT in Two Cases

Pulmonary vein (PV) stenosis is a complication of ablation therapy for arrhythmias. We report two cases with chronic lung parenchymal abnormalities showing no improvement and waxing and waning features, which were initially diagnosed as nonspecific pneumonias, and finally confirmed as PV stenosis. When a patient presents for nonspecific respiratory symptoms without evidence of infection after ablation therapy and image findings show chronic and repetitive parenchymal abnormalities confined in localized portion, the possibility of PV stenosis should be considered.

Utilidad de la biopsia percutánea core guiada por tomografía computada (TC) en lesiones pulmonares: experiencia de 7 años / Percutaneous CT-guided cutting needle biopsy of pulmonary lesions: Retrospective analysis of 153 procedures

Background: CT guided percutaneous biopsy of pulmonary lesions is a widely used technique. Aim: To evaluate the yield and complication rate of CT-guided percutaneous core biopsy of pulmonary lesions. Material and Methods: A retrospective study of 153 consecutive lung biopsies performed in a 7-yearperiod was undertaken. Patients and lesions characteristics were reviewed. The yield for the diagnosis of malignant and benign lesions and the complication rate were calculated. Lesion size and depth from the pleural surface were analyzed as potential predictive variables for occurrence of a false-negative diagnosis of malignancy. The final diagnosis was established by surgical biopsy of the lesion or clinical and imaging follow up. Results: The mean age of patients was 66 ± 14 years and 55% were mole. The final diagnosis of the lesion was malignant in 139 and benign in 14 cases (prevalence of malignancy 90.8%). For the diagnosis of malignancy, the overall yield ofthe biopsy was 91.5%o with a sensitivity of 90.6%>. A specific diagnosis of benign lesions was obtained in 5 out ofl4 biopsies (35%). We did not identify an association between the lesion size or depth and the rate of false-negative diagnosis of malignancy. The pneumothorax rate was 13.7%o (n = 21) and eight (38%) required drainage. The average lesion depth of patients that had a pneumothorax was significant greater than the cases without the complication. No major bleeding complications occurred. Conclusions: Percutaneous CT-guided cutting needle biopsies of pulmonary lesions have an excellent diagnostic accuracy for malignant pulmonary lesions, at a low complication rate.

Endovascular Stent Graft for Treatment of Complicated Spontaneous Dissection of Celiac Artery: Report of Two Cases

We report 2 cases of complicated spontaneous dissection of the celiac artery, which were successfully treated by a stent graft. The first patient was a 47-year-old man who presented with acute abdominal pain. CT scan showed ruptured saccular aneurysm with surrounding retroperitoneal hematoma. The second patient was a 57-year-old man with progressive dissecting aneurysm. Endovascular stent graft was placed in the celiac trunk to control bleeding, and to prevent rupture in each patient. Follow-up CT scans showed complete obliteration of a dissecting aneurysm.

Alterações tireoidianas associadas à radiação externa em crianças e adolescentes / Thyroid disorders associated with external radiation in children and adolescents

O efeito da radiação ionizante sobre a tireoide vem sendo estudado há várias décadas, e os acidentes nucleares têm sido a maior fonte de informação. Existe associação de hipotireoidismo, hipertireoidismo, nódulos e câncer de tireoide com a radiação, mas os limiares de dose, mecanismos de lesão e alguns fatores de risco ainda não estão bem estabelecidos. Crianças são mais suscetíveis à lesão tireoidiana por radiação e necessitam de seguimento prolongado após a exposição. Esse tema adquire maior relevância atualmente, pois um grande número de pessoas tratadas com radioterapia para câncer na infância sobrevive e poderá apresentar sequelas. Exames radiodiagnósticos também representam fonte de exposição à radiação na população pediátrica. Nesta revisão, analisamos as diferentes alterações clínico-patológicas e os mecanismos de lesões tireoidianas provocadas por tratamento radioterápico e tomografia computadorizada em crianças e adolescentes. É importante conhecer esses dados para prevenção, detecção precoce e tratamento da disfunção tireoidiana.

The effects of ionizing radiation on the thyroid have been studied for several decades, and nuclear accidents are the major source of information about the subject. There is an association of hypothyroidism, hyperthyroidism, thyroid nodules and cancer with radiation, but the threshold dose, mechanism of injury, and some risk factors have not been fully established. Children are more susceptible to thyroid injury caused by radiation and require prolonged follow-up after exposure. This issue is especially relevant nowadays, since a large number of people treated with radiation for childhood cancer survive and may have sequelae. Diagnostic radiology tests also represent a source of exposure to radiation in the pediatric population. In this review, we analyze different clinical and pathological changes, and the mechanisms of thyroid lesions caused by radiotherapy and computed tomography in children and adolescents. It is important to understand these data for prevention, early detection, and treatment of thyroid dysfunction.

Radiología diagnóstica en la embarazada: consideraciones sobre exposición a radiación y riesgo del feto / Diagnostic radiology in the pregnant: radiation exposure and risk to the fetus

El uso de exámenes de imágenes para el diagnóstico de condiciones no obstétricas puede ser requerido durante cualquier etapa del embarazo. Existe un riesgo teórico de defectos en el desarrollo fetal, el que se ha considerado no relevante con el nivel de dosis aportada por la radiología diagnóstica habitual. La comprensión de los efectos de la radiación en las diferentes etapas del desarrollo fetal y las dosis aportadas por las diferentes técnicas de imágenes debieran colaborar en la elección del tipo de examen a realizar y del mejor momento para hacerlo.

Diagnostic imaging studies can be required during any phase of the pregnancy for the diagnosis of not obstetric conditions. A theoretical risk of defects in the fetal development exists, but it has been considered insignificant at the dose level used for regular radiology practice. Comprehension of radiation effects over fetal development at different pregnancy stages and the relation between imaging modality and dose can help to make a choice, selecting the best radiologic examination and the best moment to do it.