RESUMO
BACKGROUND: Accuracy of right heart strain (RHS) measured on computed tomography pulmonary angiogram (CTPA) scans by non-radiologists is unknown. We assessed inter-observer variability of four RHS features and determined the accuracy of measurements by respiratory physicians. METHOD: 1560 consecutive patients with acute PE were identified, and those who had a CTPA and an echocardiogram within 24-h included. CTPAs were independently scored prospectively by two radiologists, two thoracic physicians and a specialist registrar. Inter-observer variability was assessed, and diagnostic accuracy compared to echocardiography. RESULTS: 182 patients (median age 62.8 years, IQR 49.8-71.5) with acute PE (7.7% high-risk, 40.7% intermediate high-risk, 31.3% intermediate low-risk and 20.3% low-risk) were included. Right ventricle to left ventricle diameter ratio (RV:LV) measurement had low inter-observer variability among the radiologists and non-radiologists with interclass correlation coefficient (ICC) of 0.95 (95%CI 0.92-0.97) and 0.96 (95%CI 0.94-0.97) respectively. RV:LV ratio had high diagnostic accuracy compared to RV dilatation on echocardiography (AUC 0.89, 95%CI 0.84-0.94 for radiologists and AUC 0.84, 95%CI 0.77-0.90 for non-radiologists). Main pulmonary artery to ascending aorta diameter ratio (MPA:Ao) measurement also had excellent agreement amongst the radiologists and non-radiologists (ICC 0.93 (95%CI 0.88-0.96) and 0.92 (95%CI 0.81-0.96) respectively). Significant variability was seen in the assessment of subjective features of RHS (leftward bowing of interventricular septum and contrast reflux into inferior vena cava) amongst the non-radiologists. CONCLUSION: RV:LV and MPA:Ao diameter ratios on CTPA measured by non-radiologists have low inter-observer variability and good agreement with radiologists, and can be reliably used where an expert report is unavailable.
Assuntos
Médicos , Embolia Pulmonar , Humanos , Pessoa de Meia-Idade , Doença Aguda , Angiografia/métodos , Variações Dependentes do Observador , Embolia Pulmonar/diagnóstico por imagem , Estudos RetrospectivosAssuntos
Estenose da Valva Aórtica/diagnóstico por imagem , Doença da Válvula Aórtica Bicúspide/diagnóstico por imagem , Implante de Prótese de Valva Cardíaca/instrumentação , Próteses Valvulares Cardíacas , Valva Mitral/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Estenose da Valva Aórtica/fisiopatologia , Estenose da Valva Aórtica/cirurgia , Doença da Válvula Aórtica Bicúspide/fisiopatologia , Doença da Válvula Aórtica Bicúspide/cirurgia , Feminino , Implante de Prótese de Valva Cardíaca/efeitos adversos , Humanos , Pessoa de Meia-Idade , Valva Mitral/fisiopatologia , Valva Mitral/cirurgia , Valor Preditivo dos Testes , Falha de PróteseRESUMO
BACKGROUND: Dual-energy CT is able to distinguish between materials based on differences in X-ray absorption at different X-ray beam energies. The strong k-edge photoelectric effect of materials with a high atomic number makes this modality ideal for identifying iodine-containing compounds. We aim to evaluate dual-energy CT for the detection of Gastrografin (GG) (diatrizoate, Bayer PLC, Reading, UK) enteric contrast medium and validate the conditions for the measurement in ex vivo samples. METHODS: Dual-energy CT acquisitions were performed to detect Gastrografin in serial dilutions of water, saline and body fluids. We also evaluated the stability of Gastrografin solutions over time at room temperature. Stool specimens were examined to validate the proposed study protocol for clinical applications. RESULTS: Concentrations as low as 0.2% of Gastrografin were reproducibly detected in vitro and ex vivo samples by DECT, with linear readings ranging from 0.2% to 25% Gastrografin. Gastrografin was shown to be stable in ex vivo biological samples, and there was no difference in detection over time. Gastrografin was detected in stool specimens when administered orally. The detection curves followed the expected saturation effect at high concentrations of iodine. CONCLUSIONS: Dual-energy CT offers a convenient, quick, reliable and reproducible method for detecting and quantifying the presence of Gastrografin in ex vivo clinical specimens. Biological solutions containing Gastrografin are stable over time. A minimum dilution level of 25% is suggested to avoid beam saturation and inaccurate results.
Assuntos
Meios de Contraste/química , Diatrizoato de Meglumina/química , Fezes/química , Tomografia Computadorizada por Raios X/métodos , Estabilidade de Medicamentos , Humanos , Técnicas In Vitro , Imagens de Fantasmas , Reprodutibilidade dos TestesRESUMO
This study investigated the effects of previous radiation therapy on outcomes from nivolumab in advanced NSCLC, and found that previous radiation therapy resulted in significantly higher survival in patients treated with nivolumab for advanced NSCLC http://bit.ly/3btOFSL.
RESUMO
INTRODUCTION: Optimal opacification of the pulmonary vasculature is a fundamental factor of a diagnostic quality computed tomography pulmonary angiogram (CTPA). This retrospective study examined the feasibility of utilising a noise-optimised monoenergetic reconstruction of the dual-energy computed tomography pulmonary angiogram (DE-CTPA) as an additional protocol to increase vessel opacification. METHOD: The study involved a retrospective analysis of 129 patients, 69 males (average age 58 years), 60 females (average age 56 years) who underwent a DE-CTPA at a tertiary referral hospital. Linear blended 120 kilovoltage (kV) images (LB120) dual-energy (DE) data sets (50% 100 kV and 50% 140 kV) were compared to noise-optimised virtual monoenergetic image reconstruction (VMI+) at 40 kiloelectron volts (VMI+40). The attenuation of the pulmonary trunk measured in Hounsfield units (HU) between the equivalent axial slices of the LB120 data set and the VMI+40 data set underwent statistical analysis via a Wilcoxon paired-sample test. RESULTS: VMI+40 (1161.500 HU) yielded a statistically significant increase in median attenuation within the pulmonary trunk compared to the LB120 (304.400 HU), with a median difference between monoenergetic reconstruction and standard dual energy of data sets of 827.5 HU (P < .001). CONCLUSIONS: VMI+40 of the DE-CTPA scan demonstrates a statistically significant increase in vessel attenuation in all cases and may have utility in reducing the rates of indeterminate or repeated studies.
Assuntos
Angiografia por Tomografia Computadorizada/métodos , Processamento de Imagem Assistida por Computador/métodos , Artéria Pulmonar/diagnóstico por imagem , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos RetrospectivosRESUMO
The retroperitoneal space is made up of multiple communicating compartments. Here we detail an unusual case of ectopic gas almost exclusively isolated to the properitoneal space, a space in communication with the retroperitoneum. This case is a reminder that when extraperitoneal gas is identified, the retroperitoneal structures should be interrogated carefully to identify a cause.
Assuntos
Enfisema/diagnóstico por imagem , Gases , Complicações Pós-Operatórias/diagnóstico por imagem , Espaço Retroperitoneal/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Diagnóstico Diferencial , Enfisema/etiologia , Humanos , Hérnia Incisional/complicações , Hérnia Incisional/diagnóstico por imagem , Hérnia Incisional/cirurgia , Perfuração Intestinal/complicações , Perfuração Intestinal/diagnóstico por imagem , Perfuração Intestinal/cirurgia , Masculino , Pessoa de Meia-Idade , NecroseRESUMO
A healthy 31-year-old man presenting with back pain was found to have multiple spinal enhancing lesions on MRI. An incidental asymptomatic large pleural effusion was identified on investigations for the back pain and pleural and pulmonary tuberculosis (TB) was subsequently diagnosed. The radiographical features on MRI spine were not typical of spinal TB and a Ga68 DOTATATE Positron Emission Tomography (PET)/CT confirmed metastatic paraganglioma with multiple bone metastases. Although metastatic paraganglioma is rare, this case highlights that even in young patients dual pathology needs to be considered. Most importantly, it is a reminder to physicians managing TB of the clues that help distinguish spinal TB from important alternative causes, including metastatic malignancy.
Assuntos
Paraganglioma/diagnóstico por imagem , Doenças Pleurais/diagnóstico por imagem , Derrame Pleural/diagnóstico por imagem , Neoplasias da Coluna Vertebral/diagnóstico por imagem , Tuberculose Pulmonar/diagnóstico por imagem , Adulto , Dor nas Costas/diagnóstico por imagem , Dor nas Costas/etiologia , Diagnóstico Diferencial , Humanos , Achados Incidentais , Masculino , Paraganglioma/complicações , Doenças Pleurais/complicações , Doenças Pleurais/microbiologia , Derrame Pleural/complicações , Derrame Pleural/microbiologia , Tomografia por Emissão de Pósitrons combinada à Tomografia Computadorizada , Neoplasias da Coluna Vertebral/complicações , Tuberculose Pulmonar/complicaçõesRESUMO
A computed tomography (CT) biopsy is a radiological procedure which involves using a needle to withdraw tissue or a fluid specimen from a lesion of interest inside a patient's body. The needle is progressively advanced into the patient's body, guided by the most recent CT scan. CT guided biopsies invariably expose patients to high dosages of radiation, due to the number of scans required whilst the needle is advanced. This study details the design of a novel method to aid biopsy procedures using infrared cameras. Two cameras are used to image the biopsy needle area, from which the proposed algorithm computes an estimate of the needle endpoint, which is projected onto the CT image space. This estimated position may be used to guide the needle between scans, and results in a reduction in the number of CT scans that need to be performed during the biopsy procedure. The authors formulate a 2D augmentation system which compensates for camera pose, and show that multiple low-cost infrared imaging devices provide a promising approach.
RESUMO
INTRODUCTION: Patients with osteodiscitis are often prescribed antibiotics prior to biopsy. There is controversy in the literature about whether antibiotic pre-treatment prior to CT-guided biopsy decreases the microbiological culture yield. Conclusions from previous studies are influenced by sample size error and selection bias. Our study, conducted in a large number of patients over a 10-year period, clarifies this issue so that best clinical practice is assured. METHODS: We performed a retrospective audit of the clinical, radiological and microbiological features of adult patients who underwent CT-guided biopsies for suspected osteodiscitis at a tertiary institution. Patients who had received intravenous antibiotic therapy in the month prior to biopsy or oral antibiotics 2 weeks prior to biopsy were considered as having had antecedent treatment. RESULTS: We initially found no significant difference in the likelihood of a positive culture between patients who had received antecedent treatment and those who had not. However, when we performed a subgroup analysis, we found that using multiple antibiotics influenced the likelihood of a positive culture. A second subgroup analysis demonstrated that pre-treatment reduced the likelihood of a positive culture. This discrepancy arose from the match between the antecedent antibiotics and the organisms' antibiotic sensitivity profile. CONCLUSION: Antibiotic treatment preceding CT-guided biopsy reduces the likelihood of a positive microbiological culture results. However, due to the often poor match, between the pre-treatment antibiotic and the organisms' antibiotic sensitivity profile, this is often not clinically apparent. Furthermore, positive cultures sensitive to the pre-treatment antibiotics can still be obtained.
Assuntos
Antibacterianos/administração & dosagem , Discite/tratamento farmacológico , Discite/patologia , Biópsia Guiada por Imagem/métodos , Tomografia Computadorizada por Raios X , Discite/microbiologia , Feminino , Humanos , Masculino , Estudos Retrospectivos , Centros de Atenção TerciáriaRESUMO
The use of immune checkpoint inhibitor (ICI) therapy in the treatment of solid organ malignancies is becoming increasingly common. This has prompted the recognition of a new class of immune-related adverse effects (irAEs) stemming from the upregulation of T-cell activity causing autoimmunity. Neurological irAEs are a rare complication of ICIs that can lead to long-term morbidity. We report a rare case of encephalopathy after treatment with pembrolizumab, to which the patient achieved durable disease response despite discontinuation of therapy. We also review the pathophysiology, incidence, clinical presentation, diagnosis, and management of neurotoxicity secondary to ICIs. Treatment requires early administration of high-dose corticosteroids, and cessation of ICI therapy is often necessary after grade 3 or 4 irAEs. However, early data suggest that neurological irAEs correlate with a favorable disease response. Consideration should also be given to the optimal duration of ICI therapy to minimize the risk of toxicity and optimize health care expenditure.
Assuntos
Anticorpos Monoclonais Humanizados/efeitos adversos , Encefalopatias/induzido quimicamente , Imunoterapia/efeitos adversos , Idoso , Humanos , MasculinoRESUMO
BACKGROUND: Controversy exists regarding the optimal lead position for chronic right ventricular (RV) pacing. Placing a lead at the RV septum relies upon fluoroscopy assisted by a surface 12-lead electrocardiogram (ECG). We compared the postimplant lead position determined by ECG-gated multidetector contrast-enhanced computed tomography (MDCT) with the position derived from the surface 12-lead ECG. METHODS: Eighteen patients with permanent RV leads were prospectively enrolled. Leads were placed in the RV septum (RVS) in 10 and the RV apex (RVA) in eight using fluoroscopy with anteroposterior and left anterior oblique 30° views. All patients underwent MDCT imaging and paced ECG analysis. ECG criteria were: QRS duration; QRS axis; positive or negative net QRS amplitude in leads I, aVL, V1, and V6; presence of notching in the inferior leads; and transition point in precordial leads at or after V4. RESULTS: Of the 10 leads implanted in the RVS, computed tomography (CT) imaging revealed seven to be at the anterior RV wall, two at the anteroseptal junction, and one in the true septum. For the eight RVA leads, four were anterior, two septal, and two anteroseptal. All leads implanted in the RVS met at least one ECG criteria (median 3, range 1-6). However, no criteria were specific for septal position as judged by MDCT. Mean QRS duration was 160 ± 24 ms in the RVS group compared with 168 ± 14 ms for RVA pacing (P = 0.38). CONCLUSIONS: We conclude that the surface ECG is not sufficiently accurate to determine RV septal lead tip position compared to cardiac CT.
Assuntos
Fibrilação Atrial/cirurgia , Terapia de Ressincronização Cardíaca/métodos , Ablação por Cateter/métodos , Eletrocardiografia/métodos , Cirurgia Assistida por Computador/métodos , Septo Interventricular/diagnóstico por imagem , Septo Interventricular/cirurgia , Mapeamento Potencial de Superfície Corporal/métodos , Técnicas de Imagem Cardíaca/métodos , Feminino , Fluoroscopia/métodos , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/cirurgia , Humanos , Masculino , Pessoa de Meia-Idade , Tomografia Computadorizada Multidetectores/métodos , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
BACKGROUND: Right ventricular nonapical (RVNA) pacing may reduce the risk of heart failure. Fluoroscopy is the standard approach to determine lead tip position, but is inaccurate. We compared cardiac computed tomography (CT), magnetic resonance imaging (MRI), two-dimensional and three-dimensional transthoracic echocardiography (TTE), and chest x-ray (CXR) to assess which provides the optimal assessment of right ventricular (RV) lead tip position. METHODS: Eighteen patients with MRI-conditional pacemakers (10 RVNA and eight apical [RVA] leads) underwent contrast CT, MRI, TTE, and a standard postimplant posteroanterior and lateral CXR. To compare images, the RV was arbitrarily partitioned into three long-axis segments (right ventricular outflow tract, middle, and apex), and two short-axis segments (septal and nonseptal). Agreement between modalities was assessed. RESULTS: RV lead tip position was identified in all patients on CT, TTE, and CXR, but was not identified in seven (39%) patients on MRI due to device-related artifact. Of 10 leads deemed to be nonapical/septal during implant, 70% were identified as nonapical on CXR, 60% on CT, 60% on MRI, and 80% on TTE. On CT imaging only 10% were truly septal, 20% on MRI, 30% on CXR, and 80% on TTE. Agreement was better between modalities when assessing position of the designated RVA leads. CONCLUSION: During implant leads intended for the septum are not confirmed as such on subsequent imaging, and marked heterogeneity is apparent between modalities. MRI is limited by artifact, and discrepancy exists between TTE and CT in identifying septal lead position. CT gave the clearest definition of lead tip position.
Assuntos
Eletrodos Implantados , Ventrículos do Coração/diagnóstico por imagem , Ventrículos do Coração/cirurgia , Marca-Passo Artificial , Implantação de Prótese/métodos , Cirurgia Assistida por Computador/métodos , Ecocardiografia/métodos , Feminino , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Método Simples-Cego , Tomografia Computadorizada por Raios X/métodosRESUMO
INTRODUCTION: Targeted spinal steroid injections are effective in reducing back pain in selected patient populations and carry a small risk of significant adverse neurological outcomes. Recent recommendations are for the use of non-particulate steroid agents for all spinal injections to reduce the risk of neurovascular embolic adverse events. Many injections have used a combination of local anaesthetic agent with the steroid. At our institutions, we have recently observed interactions between ropivacaine and dexamethasone combinations ascribed to the incompatibility of the former with alkaline solutions, resulting in rapid crystallisation. This study has further investigated the combinations of commonly used local anaesthetic and steroid combinations to determine if such precipitation effects are more widespread. METHODS: The commonly used local anaesthetics (lignocaine, bupivacaine, ropivacaine) and the non-particulate steroid dexamethasone sodium phosphate combinations were evaluated macroscopically, microscopically, and pH values measured. Where crystallisation was observed the rate of precipitation and crystal size was measured. Contamination of ropivacaine with sodium bicarbonate solution was also evaluated. Particulate size of the particulate steroid agent betamethasone acetate was evaluated as a comparison. RESULTS: All mixtures of ropivacaine and the non-particulate dexamethasone sodium phosphate assessed demonstrated a pH-dependent crystallisation of the solution. No precipitation was demonstrated with the combinations of dexamethasone and lignocaine or bupivacaine. Contamination of ropivacaine with residual sodium bicarbonate in a drawing up needle following air clearing had a precipitation effect. CONCLUSION: We describe the effect of crystallisation with the combination of ropivacaine and the non-particulate steroid, dexamethasone sodium phosphate, a mixture that has been used in the literature for targeted pain injections. As this may be considered a non-particulate steroid/anaesthetic injectate, this would potentially carry increased risk if inadvertent intravascular injection occurred during a targeted spinal injection, as has been described with particulate steroid agents. This is due to the elevated pH of dexamethasone and the incompatibility of ropivacaine with alkaline solutions.
Assuntos
Amidas/química , Analgesia Epidural , Dexametasona/química , Dor Lombar/tratamento farmacológico , Anestésicos Locais , Coloides/síntese química , Contraindicações , Dexametasona/administração & dosagem , Combinação de Medicamentos , Interações Medicamentosas , Humanos , Concentração de Íons de Hidrogênio , Teste de Materiais , Tamanho da Partícula , Ropivacaina , ViscosidadeRESUMO
INTRODUCTION: Stereoscopic vision is a critical part of the human visual system, conveying more information than two-dimensional, monoscopic observation alone. This study aimed to quantify the contribution of stereoscopy in assessment of radiographic data, using widely available three-dimensional (3D)-capable display monitors by assessing whether stereoscopic viewing improved the characterisation of cerebral aneurysms. METHODS: Nine radiology registrars were shown 40 different volume-rendered (VR) models of cerebral computed tomography angiograms (CTAs), each in both monoscopic and stereoscopic format and then asked to record aneurysm characteristics on short multiple-choice answer sheets. The monitor used was a current model commercially available 3D television. Responses were marked against a gold standard of assessments made by a consultant radiologist, using the original CT planar images on a diagnostic radiology computer workstation. RESULTS: The participants' results were fairly homogenous, with most showing no difference in diagnosis using stereoscopic VR models. One participant performed better on the monoscopic VR models. On average, monoscopic VRs achieved a slightly better diagnosis by 2.0%. CONCLUSIONS: Stereoscopy has a long history, but it has only recently become technically feasible for stored cross-sectional data to be adequately reformatted and displayed in this format. Scant literature exists to quantify the technology's possible contribution to medical imaging - this study attempts to build on this limited knowledge base and promote discussion within the field. Stereoscopic viewing of images should be further investigated and may well eventually find a permanent place in procedural and diagnostic medical imaging.