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BACKGROUND. CT-based criteria for assessing the gastrointestinal stromal tumor (GIST) response to tyrosine kinase inhibitor (TKI) therapy are limited in part because tumor attenuation is influenced by treatment-related changes including hemorrhage and calcification. The iodine concentration may be less impacted by such changes. OBJECTIVE. The purpose of this study was to determine whether the dual-energy CT (DECT) vital iodine tumor burden (TB) allows improved differentiation between treatment responders and nonresponders among patients with metastatic GIST who are undergoing TKI therapy compared with established CT and PET/CT criteria. METHODS. An anthropomorphic phantom with spherical inserts mimicking GIST lesions of varying iodine concentrations and having nonenhancing central necrotic cores underwent DECT to determine a threshold iodine concentration. Forty patients (25 women and 15 men; median age, 57 years) who were treated with TKI for metastatic GIST were retrospectively evaluated. Patients underwent baseline and follow-up DECT and FDG PET/CT. Response assessment was performed using RECIST 1.1, modified Choi (mChoi) criteria, vascular tumor burden (VTB) criteria, DECT vital iodine TB criteria, and European Organization for Research and Treatment of Cancer (EORTC) PET criteria. DECT vital iodine TB criteria used the same percentage changes as RECIST 1.1 response categories. Progression-free survival was compared between responders and nonresponders for each response criterion by use of Cox proportional hazard ratios and Harrell C-indexes (i.e., concordance indexes). RESULTS. The phantom experiment identified a threshold of 0.5 mg/mL to differentiate vital from nonvital tissue. With use of the DECT vital iodine TB, median progression-free survival was significantly different between responders and nonresponders (623 vs 104 days; p < .001).. For nonresponders versus responders, the hazard ratio for disease progression for DECT vital iodine TB was 6.9 versus 7.6 for EORTC PET criteria, 3.3 for VTB criteria, 2.3 for RECIST 1.1, and 2.1 for mChoi criteria. The C-index was 0.74 for EORTC PET criteria, 0.73 for DECT vital iodine TB criteria, 0.67 for VTB criteria, 0.61 for RECIST 1.1, and 0.58 for mChoi criteria. The C-index was significantly greater for DECT vital iodine TB criteria than for RECIST 1.1 (p = .02) and mChoi criteria (p = .002), but it was not different from that for VTB and EORTC PET criteria (p > .05). CONCLUSION. DECT vital iodine TB criteria showed performance comparable to that of EORTC PET criteria and outperformed RECIST 1.1 and mChoi criteria for response assessment of metastatic GIST treated with TKI therapy. CLINICAL IMPACT. DECT vital iodine TB could help guide early management decisions in patients receiving TKI therapy.
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Tumores del Estroma Gastrointestinal , Yodo , Neoplasias Primarias Secundarias , Femenino , Fluorodesoxiglucosa F18 , Tumores del Estroma Gastrointestinal/diagnóstico por imagen , Tumores del Estroma Gastrointestinal/tratamiento farmacológico , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Tomografía de Emisión de Positrones , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodos , Carga TumoralRESUMEN
Purpose To prospectively evaluate the accuracy of left ventricle (LV) analysis with a two-dimensional real-time cine true fast imaging with steady-state precession (trueFISP) magnetic resonance (MR) imaging sequence featuring sparse data sampling with iterative reconstruction (SSIR) performed with and without breath-hold (BH) commands at 3.0 T. Materials and Methods Ten control subjects (mean age, 35 years; range, 25-56 years) and 60 patients scheduled to undergo a routine cardiac examination that included LV analysis (mean age, 58 years; range, 20-86 years) underwent a fully sampled segmented multiple BH cine sequence (standard of reference) and a prototype undersampled SSIR sequence performed during a single BH and during free breathing (non-BH imaging). Quantitative analysis of LV function and mass was performed. Linear regression, Bland-Altman analysis, and paired t testing were performed. Results Similar to the results in control subjects, analysis of the 60 patients showed excellent correlation with the standard of reference for single-BH SSIR (r = 0.93-0.99) and non-BH SSIR (r = 0.92-0.98) for LV ejection fraction (EF), volume, and mass (P < .0001 for all). Irrespective of breath holding, LV end-diastolic mass was overestimated with SSIR (standard of reference: 163.9 g ± 58.9, single-BH SSIR: 178.5 g ± 62.0 [P < .0001], non-BH SSIR: 175.3 g ± 63.7 [P < .0001]); the other parameters were not significantly different (EF: 49.3% ± 11.9 with standard of reference, 48.8% ± 11.8 with single-BH SSIR, 48.8% ± 11 with non-BH SSIR; P = .03 and P = .12, respectively). Bland-Altman analysis showed similar measurement errors for single-BH SSIR and non-BH SSIR when compared with standard of reference measurements for EF, volume, and mass. Conclusion Assessment of LV function with SSIR at 3.0 T is noninferior to the standard of reference irrespective of BH commands. LV mass, however, is overestimated with SSIR. © RSNA, 2016 Online supplemental material is available for this article.
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Ventrículos Cardíacos/diagnóstico por imagen , Ventrículos Cardíacos/fisiopatología , Imagen por Resonancia Cinemagnética/métodos , Disfunción Ventricular Izquierda/diagnóstico por imagen , Función Ventricular Izquierda/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Contencion de la Respiración , Técnicas de Imagen Sincronizada Cardíacas , Estudios de Casos y Controles , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Disfunción Ventricular Izquierda/fisiopatologíaRESUMEN
OBJECTIVES AND BACKGROUND: Atrial fibrillation (AF) is associated with clinical deterioration, stroke and disability in patients with hypertrophic cardiomyopathy (HCM). Therefore, the objective of this study was to evaluated cardiac magnetic resonance (CMR)-derived determinants for the occurrence of AF in patients with HCM. METHODS: 98 Patients with HCM and 30 healthy controls underwent CMR and were followed-up for 6 ± 3 years. RESULTS: 19 (19.4%) patients presented with AF at initial diagnosis, 19 (19.4%) developed AF during follow-up and 60 (61.2%) remained in sinus rhythm (SR). Compared to healthy controls, patients with HCM who remained in SR presented with significantly increased left ventricular mass, an elevated left ventricular remodeling index, enlarged left atrial volumes and reduced septal mitral annular plane systolic excursion (MAPSE) compared to healthy controls. Whereas HCM patients who presented with AF at initial diagnosis and those who developed AF during follow-up additionally presented with reduced tricuspid annular plane systolic excursion (TAPSE) and right atrial (RA) dilatation. Receiver-operator curve analysis indicated good predictive performance of TAPSE, RA diameter and septal MAPSE (AUC 0.73, 0.69 and 0.71, respectively) to detect patients at risk of developing AF. CONCLUSION: Reduced MAPSE measurements and enlarged LA volumes seems to be a common feature in patients with HCM, whereas reduced TAPSE and RA dilatation only seem to be altered in patients with history of AF and those developing AF. Therefore, they could serve as easy determinable markers of AF in patients with HCM.
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Fibrilación Atrial/diagnóstico por imagen , Cardiomiopatía Hipertrófica/diagnóstico por imagen , Ventrículos Cardíacos/diagnóstico por imagen , Imagen por Resonancia Magnética , Adulto , Anciano , Fibrilación Atrial/fisiopatología , Cardiomiopatía Hipertrófica/fisiopatología , Medios de Contraste/química , Femenino , Gadolinio/química , Atrios Cardíacos/diagnóstico por imagen , Atrios Cardíacos/fisiopatología , Ventrículos Cardíacos/fisiopatología , Humanos , Masculino , Persona de Mediana Edad , RadiografíaRESUMEN
BACKGROUND: A standardized imaging proposal evaluating implanted left atrial appendage (LAA) occlusion devices by cardiac computed tomography angiography (cCTA) has never been investigated. METHODS: cCTA datasets were acquired on a 3(rd) generation dual-source CT system and reconstructed with a slice thickness of 0.5 mm. An interdisciplinary evaluation was performed by two interventional cardiologists and one radiologist on a 3D multi-planar workstation. A standardized multi-planar reconstruction algorithm was developed in order to assess relevant clinical aspects of implanted LAA occlusion devices being outlined within a pictorial essay. RESULTS: The following clinical aspects of implanted LAA occlusion devices were evaluated within the most appropriate cCTA multi-planar reconstruction: (1) topography to neighboring structures, (2) peri-device leaks, (3) coverage of LAA lobes, (4) indirect signs of neo-endothelialization. These are illustrated within concise CT imaging examples emphasizing the potential value of the proposed cCTA imaging algorithm: Starting from anatomical cCTA planes and stepwise angulation planes perpendicular to the base of the LAA devices generates an optimal LAA Occluder View for post-implantation Evaluation (LOVE). Aligned true axial, sagittal and coronal LOVE planes offer a standardized and detailed evaluation of LAA occlusion devices after percutaneous implantation. CONCLUSIONS: This pictorial essay presents a standardized imaging proposal by cCTA using multi-planar reconstructions that enables systematical follow-up and comparison of patients after LAA occlusion device implantation.
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Apéndice Atrial/diagnóstico por imagen , Atrios Cardíacos/cirugía , Interpretación de Imagen Asistida por Computador/normas , Algoritmos , Apéndice Atrial/cirugía , Atrios Cardíacos/diagnóstico por imagen , Humanos , Dispositivo Oclusor Septal , Tomografía Computarizada por Rayos X/normasRESUMEN
OBJECTIVES: To prospectively evaluate radiation dose and image quality of a third generation dual-source CT (DSCT) without z-axis filter behind the patient for temporal bone CT. METHODS: Forty-five patients were either examined on a first, second, or third generation DSCT in an ultra-high-resolution (UHR) temporal bone-imaging mode. On the third generation DSCT system, the tighter focal spot of 0.2 mm(2) removes the necessity for an additional z-axis-filter, leading to an improved z-axis radiation dose efficiency. Images of 0.4 mm were reconstructed using standard filtered-back-projection or iterative reconstruction (IR) technique for previous generations of DSCT and a novel IR algorithm for the third generation DSCT. Radiation dose and image quality were compared between the three DSCT systems. RESULTS: The statistically significantly highest subjective and objective image quality was evaluated for the third generation DSCT when compared to the first or second generation DSCT systems (all p < 0.05). Total effective dose was 63%/39% lower for the third generation examination as compared to the first and second generation DSCT. CONCLUSIONS: Temporal bone imaging without z-axis-UHR-filter and a novel third generation IR algorithm allows for significantly higher image quality while lowering effective dose when compared to the first two generations of DSCTs. KEY POINTS: ⢠Omitting the z-axis-filter allows a reduction in radiation dose of 50% ⢠A smaller focal spot of 0.2 mm (2) significantly improves spatial resolution ⢠Ultra-high-resolution temporal-bone-CT helps to gain diagnostic information of the middle/inner ear.
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Algoritmos , Diagnóstico por Imagen/métodos , Tomografía Computarizada Multidetector/métodos , Hueso Temporal/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Dosis de Radiación , Reproducibilidad de los ResultadosRESUMEN
PURPOSE: To prospectively evaluate radiation and contrast medium requirements for performing high-pitch coronary computed tomographic (CT) angiography at 70 kV using a third-generation dual-source CT system in comparison to a second-generation dual-source CT system. MATERIALS AND METHODS: All patients gave informed consent for this institutional review board-approved study. Forty-five patients (median age, 52 years; 27 men) were imaged in high-pitch mode with a third-generation dual-source CT system at 70 kV (n = 15) or with a second-generation dual-source CT system at 80 or 100 kV (n = 15 for each). Tube voltage was based on body mass index: 80 or 70 kV for less than 26 kg/m(2) versus 100 kV for 26-30 kg/m(2). For the 80- and 100-kV protocols, 80 mL of contrast material was injected, versus 45 mL for the 70-kV protocol. Data were reconstructed by using a second-generation iterative reconstruction algorithm for second-generation dual-source CT and a recently introduced third-generation iterative reconstruction algorithm for third-generation dual-source CT. Objective image quality was measured for various regions of interest, and subjective image quality was evaluated with a five-point Likert scale. RESULTS: The signal-to-noise ratio of the coronary CT angiography studies acquired with 70 kV was significantly higher (70 kV: 14.3-17.6 vs 80 kV: 7.1-12.9 vs 100 kV: 9.8-12.9; P < .0497) than those acquired with the other two protocols for all coronary arteries. Qualitative image quality analyses revealed no significant differences between the three CT angiography protocols (median score, 5; P > .05). The mean effective dose was 75% and 108% higher (0.92 mSv ± 0.3 [standard deviation] and 0.78 mSv ± 0.2 vs 0.44 mSv ± 0.1; P < .0001), respectively, for the 80- and 100-kV CT angiography protocols than for the 70-kV CT angiography protocol. CONCLUSION: In nonobese patients, third-generation high-pitch coronary dual-source CT angiography at 70 kV results in robust image quality for studying the coronary arteries, at significantly reduced radiation dose (0.44 mSv) and contrast medium volume (45 mL), thus enabling substantial radiation dose and contrast medium savings as compared with second-generation dual-source CT.
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Angiografía Coronaria/métodos , Enfermedad Coronaria/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Técnicas de Imagen Sincronizada Cardíacas , Medios de Contraste , Angiografía Coronaria/instrumentación , Electrocardiografía , Femenino , Humanos , Yopamidol/análogos & derivados , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador , Tomografía Computarizada por Rayos X/instrumentaciónRESUMEN
PURPOSE: Pulmonary embolism (PE) occurs frequently in patients with malignant melanoma (MM). The aim of this study is to determine the incidence of PE in patients with MM and to assess the clinical characteristics and mortality of MM patients with PE. MATERIAL AND METHODS: Medical records from 381 MM patients who underwent contrast-enhanced computed tomography were evaluated. Imaging parameters including location of PE and measurements of right heart dysfunction and clinical parameters including D-Dimer levels, local and distant tumor stage and time of death were analyzed. RESULTS: PE was found in 23/381 (6%) MM patients, whereby 17/23 (74%) were detected incidentally and only 6/23 (26%) were symptomatic. The presence of PE significantly correlated with elevated D-Dimers (p < 0.001), right ventricular dysfunction (p = 0.04), higher local tumor stage (≥T3) (p = 0.05), presence of visceral (p = 0.02) or cerebral metastases (p = 0.03) and increased mortality (p = 0.05). Further, patients with central PE showed an increased mortality compared to peripheral PE (p = 0.03), but no correlation was found between the localization of PE and the occurrence of clinical symptoms (p = 0.36). CONCLUSION: PE in patients with MM often occurs without clinical symptoms and is indicative for advanced disease and a poorer prognosis.
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Melanoma , Embolia Pulmonar , Disfunción Ventricular Derecha , Humanos , Incidencia , Melanoma/diagnóstico por imagen , Embolia Pulmonar/diagnóstico por imagen , Embolia Pulmonar/epidemiología , Estudios Retrospectivos , Disfunción Ventricular Derecha/etiologíaAsunto(s)
Seno Coronario/diagnóstico por imagen , Calcificación Vascular/diagnóstico por imagen , Anciano , Malformaciones Arteriovenosas/diagnóstico por imagen , Malformaciones Arteriovenosas/patología , Constricción Patológica/diagnóstico por imagen , Constricción Patológica/patología , Seno Coronario/anomalías , Femenino , Tomografía Computarizada Cuatridimensional , Cardiopatías Congénitas/diagnóstico por imagen , Cardiopatías Congénitas/patología , Humanos , Angiografía por Resonancia Magnética , Imagen Multimodal , Calcificación Vascular/patologíaRESUMEN
PURPOSE: To bridge neo-endothelialization (NE) of implanted left atrial appendage closure (LAA/LAAC) devices, dual antiplatelet therapy is prescribed. Cardiac computed tomography angiography (cCTA) has been proposed for the evaluation of interventional LAAC. This prospective longitudinal observational study applied a standardized imaging protocol to detect progression of NE of LAAC devices 6 months after implantation. METHODS: Consecutive cCTA datasets of patients six months after LAAC were acquired and the standardized multi-planar reconstruction LAA occluder view for post-implantation evaluation (LOVE) algorithm was used. Residual flow of contrast agent inside the LAA without a peri-device leak (PDL) was defined as incomplete neo-endothelialization. Absence of residual flow was defined as complete neo-endothelialization. Since PDL allows residual flow in the LAA, irrespective of neoendothelialization, PDL were excluded from this study. Diabetes mellitus, liver disease, body-mass-index, age, device sizes and type will be assessed as predictors for incomplete NE. RESULTS: 53 consecutive patients were recruited for cCTA imaging. 36 (68%) showed no PDL and were included in the study (median age 77 years, 19% female). At median follow-up of 6 months (median 180 days, IQR 178-180), 44% of patients showed complete NE compared to 56% with NE still incomplete. Age, BMI, device type and size as well as prevalence of diabetes mellitus and liver disease did not show significant correlation with the completeness of NE. CONCLUSION: This pilot study showed that neo-endothelialization is still incomplete in a majority of patients at mid-term follow-up of 6 months after successful LAAC therapy. Further investigation on the consequences of incomplete endothelialization is needed to guide antiplatelet therapy schedules.
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Apéndice Atrial , Fibrilación Atrial , Dispositivo Oclusor Septal , Apéndice Atrial/diagnóstico por imagen , Fibrilación Atrial/diagnóstico por imagen , Cateterismo Cardíaco/efectos adversos , Ecocardiografía Transesofágica , Femenino , Humanos , Recién Nacido , Masculino , Proyectos Piloto , Valor Predictivo de las Pruebas , Estudios Prospectivos , Resultado del TratamientoRESUMEN
As stated by the Fleischner Society, an additional computed tomography (CT) scan in expiration is beneficial in patients with chronic obstructive pulmonary disease (COPD). It was thus the aim of this study to evaluate the radiation risk of a state-of-the-art paired inspiratory-expiratory chest scan compared to inspiration-only examinations. Radiation doses to 28 organs were determined for 824 COPD patients undergoing routine chest examinations at three different CT systems-a conventional multi-slice CT (MSCT), a 2nd generation (2nd-DSCT), and 3rd generation dual-source CT (3rd-DSCT). Patients examined at the 3rd-DSCT received a paired inspiratory-expiratory scan. Organ doses, effective doses, and lifetime attributable cancer risks (LAR) were calculated. All organ and effective doses were significantly lower for the paired inspiratory-expiratory protocol (effective doses: 4.3 ± 1.5 mSv (MSCT), 3.0 ± 1.2 mSv (2nd-DSCT), and 2.0 ± 0.8 mSv (3rd-DSCT)). Accordingly, LAR was lowest for the paired protocol with an estimate of 0.025 % and 0.013% for female and male patients (50 years) respectively. Image quality was not compromised. Paired inspiratory-expiratory scans can be acquired on 3rd-DSCT systems at substantially lower dose and risk levels when compared to inspiration-only scans at conventional CT systems, offering promising prospects for improved COPD diagnosis.
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BACKGROUND: Local recurrence (LR) of retroperitoneal soft tissue sarcoma (RPS) is a common and life-threatening event. The evaluation of the exact anatomical patterns of local recurrence might help to improve local treatment in RPS. METHODS: Of our local database we extracted ten patients with LR of RPS with axial MRI and/or CT datasets of the primary tumor (PT) and the LR. Using the Osirix DICOM viewer Version v.3.9.4 64-bit (Pixmeo, Geneva, Switzerland) we performed a three-step fusion algorithm consisting of: a) 3-point co-registration of the axial datasets depicting the PT and the LR using three abdominal landmarks b) re-orientation of the datasets and c) image fusion. We evaluated the feasibility of this technique with regard to categorizing the localization of LR as within or distant from the PT. RESULTS: Fusion imaging was feasible in seven out of ten patients. In the other three patients anatomical shifting of organs after surgery led to a relevant mismatch of anatomical landmarks and impeded interpretation of the fused images. In five of seven patients with successful fusion imaging, local recurrences were located within the anatomical borders of the primary tumor, in two out of seven patients local recurrences were distant to the primary. CONCLUSIONS: Fusion imaging of primary tumors and local recurrences is feasible in most patients with RPS. Most local recurrences occurred within the anatomical localization of the primary tumor. For further investigations validation of the technique in larger patient cohorts is required.
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Procesamiento de Imagen Asistido por Computador/métodos , Imagen por Resonancia Magnética/métodos , Recurrencia Local de Neoplasia/patología , Neoplasias Retroperitoneales/patología , Sarcoma/patología , Tomografía Computarizada por Rayos X/métodos , Adulto , Anciano , Femenino , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Recurrencia Local de Neoplasia/diagnóstico por imagen , Recurrencia Local de Neoplasia/cirugía , Proyectos Piloto , Pronóstico , Estudios Prospectivos , Neoplasias Retroperitoneales/diagnóstico por imagen , Neoplasias Retroperitoneales/cirugía , Sarcoma/diagnóstico por imagen , Sarcoma/cirugíaRESUMEN
OBJECTIVES: The aim of this study was to establish quantitative CT (qCT) parameters for pathophysiological understanding and clinical use in patients with acute respiratory distress syndrome (ARDS). The most promising parameter is introduced. MATERIALS AND METHODS: 28 intubated patients with ARDS obtained a conventional CT scan in end-expiratory breathhold within the first 48 hours after admission to intensive care unit (ICU). Following manual segmentation, 137 volume- and lung weight-associated qCT parameters were correlated with 71 clinical parameters such as blood gases, applied ventilation pressures, pulse contour cardiac output measurements and established status and prognosis scores (SOFA, SAPS II). RESULTS: Of all examined qCT parameters, excess lung weight (ELW), i.e. the difference between a patient's current lung weight and the virtual lung weight of a healthy person at the same height, displayed the most significant results. ELW correlated significantly with the amount of inflated lung tissue [%] (p<0.0001; r = -0.66) and was closely associated with the amount of extravascular lung water (EVLW) (p<0.0001; r = 0.72). More substantially than the oxygenation index (PaO2/FiO2) or any other clinical parameter it correlated with the patients' mean SOFA- (p<0.0001, r = 0.69) and SAPS II-Score (p = 0.0005, r = 0.62). Patients who did not survive intensive care treatment displayed higher values of ELW in the initial CT scans. CONCLUSIONS: ELW could serve as a non-invasive method to quantify the amount of pulmonary oedema. It might serve as an early radiological marker of severity in patients with ARDS.
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Pulmón/diagnóstico por imagen , Edema Pulmonar/diagnóstico , Síndrome de Dificultad Respiratoria/diagnóstico , Tomografía Computarizada por Rayos X , Adulto , Anciano , Estudios de Factibilidad , Femenino , Mortalidad Hospitalaria , Humanos , Unidades de Cuidados Intensivos/estadística & datos numéricos , Pulmón/fisiopatología , Mediciones del Volumen Pulmonar/métodos , Masculino , Persona de Mediana Edad , Edema Pulmonar/etiología , Edema Pulmonar/mortalidad , Edema Pulmonar/fisiopatología , Síndrome de Dificultad Respiratoria/complicaciones , Síndrome de Dificultad Respiratoria/mortalidad , Síndrome de Dificultad Respiratoria/fisiopatología , Pruebas de Función Respiratoria , Índice de Severidad de la EnfermedadRESUMEN
OBJECTIVE: To compare the performance of an 18-gauge nonfenestrated catheter (18-NFC) with a 22-gauge fenestrated catheter (22-FC) for cardiac CT angiography (CCTA) in patients with suspected coronary heart disease. SUBJECTS AND METHODS: 74 consecutive patients imaged on a 2nd generation dual-source CT with arterial phase CCTA were included in this retrospective investigation to either an 18-NFC or 22-FC. In comparison to the 18-NFC, the 22-FC has three additional perforations for contrast agent dispersal proximal to the tip. We examined the two groups for differences in their average attenuation in the right and left ventricles (RV, LV) and in the atrium (RA, LA) as well as in the proximal right coronary artery (RCA) and the left main coronary artery (LM). The averages were calculated for both the 18-NFC and 22-FC. RESULTS: Catheters were successfully placed on the first attempt 97% (36/37) for 18-NFC and 95% (35/37) for the 22-FC. The following enhancement levels were measured: 22-FC (in Hounsfield-Units (HU)): RV = 203±29, LV = 523±36, RA = 198±29, LA = 519±38, RCA = 547±26, LM = 562±25; 18-NFC: RV = 146±26, LV = 464±32, RA = 141±24, LA = 438±35, RCA = 501±23, LM = 523±23; RV (p = 0,03), LV (p = 0.12), RA (p = 0.02), LA (p = 0.04), RCA (p = 0.3), LM (p = 0.33). CONCLUSION: No significant differences in attenuation levels as well as in image quality of the coronary arteries were found between NFC and FC. Nevertheless, the 22-gauge FC examinations showed significantly higher attenuation in the left and right atrium as well as the right ventricle. Patients with poor venous access may benefit from a smaller gauge catheter that can deliver sufficiently high flow rates for CCTA.
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Angiografía por Tomografía Computarizada/instrumentación , Angiografía Coronaria/instrumentación , Enfermedad Coronaria/diagnóstico por imagen , Dispositivos de Acceso Vascular , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Medios de Contraste/administración & dosificación , Diseño de Equipo , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
PURPOSE: The study aimed to compare morphological and anatomic plaque markers derived from coronary computed tomography angiography (cCTA) for the detection of lesion specific ischemia with invasive instantaneous wave free ratio (iFR®) as the reference standard. METHODS: In our prospective study, we enrolled patients with suspected coronary artery disease (CAD), who had undergone cCTA, using a low-dose third-generation dual-source CT and invasive coronary angiography (ICA) with iFR® measurement. Various plaque markers were assessed on cCTA. Discriminatory power of these markers for the detection of ischemia-inducing coronary artery disease was evaluated against invasive iFR®. RESULTS: Our study cohort included 39 patients (66.6 ± 12.0 years, 72 % male). Among 54 vessel-specific lesions, 15 lesions (28 %) were characterized as hemodynamically significant by iFR® ≤0.89. The area under the curve (AUC) of lesion length/ minimal luminal diameter4 (LL/MLD4) (0.84) was greater than the AUC of minimal luminal area (MLA) (0.82), MLD (0.81), the degree of luminal diameter stenosis (0.81), corrected coronary opacification (CCO) (0.79), remodeling index (RI) (0.75), and percentage aggregate plaque volume (%APV) (0.72). LL, vessel volume (VV), total plaque volume (TPV), calcified and non-calcified plaque volume (CPV and NCPV) did not reach statistical significance and were unable to discriminate between vessels with and without ischemia-inducing coronary stenosis. CONCLUSION: LL/MLD4, MLA, MLD, the degree of luminal diameter stenosis, CCO, RI, and %APV derived from cCTA can support the detection of hemodynamically significant coronary stenosis as compared with iFR®, with LL/MLD4 showing the greatest discriminatory power.
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Estenosis Coronaria/diagnóstico por imagen , Hemodinámica/fisiología , Placa Aterosclerótica/diagnóstico por imagen , Anciano , Área Bajo la Curva , Biomarcadores/metabolismo , Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Enfermedad de la Arteria Coronaria/fisiopatología , Estenosis Coronaria/fisiopatología , Femenino , Reserva del Flujo Fraccional Miocárdico/fisiología , Humanos , Masculino , Persona de Mediana Edad , Placa Aterosclerótica/fisiopatología , Estudios Prospectivos , Estudios Retrospectivos , Tomografía Computarizada por Rayos X/métodosRESUMEN
BACKGROUND: Fractional flow reserve based on coronary CT angiography (CT-FFR) is gaining importance for non-invasive hemodynamic assessment of coronary artery disease (CAD). We evaluated the on-site CT-FFR with a machine learning algorithm (CT-FFRML) for the detection of hemodynamically significant coronary artery stenosis in comparison to the invasive reference standard of instantaneous wave free ratio (iFR®). METHODS: This study evaluated patients with CAD who had a clinically indicated coronary computed tomography angiography (cCTA) and underwent invasive coronary angiography (ICA) with iFR®-measurements. Standard cCTA studies were acquired with third-generation dual-source computed tomography and analyzed with on-site prototype CT-FFRML software. RESULTS: We enrolled 40 patients (73% males, mean age 67 ± 12 years) who had iFR®-measurement and CT-FFRML calculation. The mean calculation time of CT-FFRML values was 11 ± 2 min. The CT-FFRML algorithm showed, on per-patient and per-lesion level, respectively, a sensitivity of 92% (95% CI 64-99%) and 87% (95% CI 59-98%), a specificity of 96% (95% CI 81-99%) and 95% (95% CI 84-99%), a positive predictive value of 92% (95% CI 64-99%), and 87% (95% CI 59-98%), and a negative predictive value of 96% (95% CI 81-99%) and 95% (95% CI 84-99%). The area under the receiver operating characteristic curve for CT-FFRML on per-lesion level was 0.97 (95% CI 0.91-1.00). Per lesion, the Pearson's correlation between the CT-FFRML and iFR® showed a strong correlation of r = 0.82 (p < 0.0001; 95% CI 0.715-0.920). CONCLUSION: On-site CT-FFRML correlated well with the invasive reference standard of iFR® and allowed for the non-invasive detection of hemodynamically significant coronary stenosis.
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Algoritmos , Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Estenosis Coronaria/diagnóstico , Vasos Coronarios/diagnóstico por imagen , Reserva del Flujo Fraccional Miocárdico/fisiología , Aprendizaje Automático , Anciano , Estenosis Coronaria/fisiopatología , Vasos Coronarios/fisiopatología , Femenino , Estudios de Seguimiento , Hemodinámica/fisiología , Humanos , Masculino , Pronóstico , Estudios ProspectivosRESUMEN
BACKGROUND: Recommendations regarding decompression of tension pneumothorax in small children are scarce and mainly transferred from the adult literature without existing evidence for the paediatric population. This CT-based study evaluates chest wall thickness, width of the intercostal space (ICS) and risk of injury to vital structures by needle decompression in children. METHODS: Chest wall thickness, width of the intercostal space and depth to vital structures were measured and evaluated at 2nd ICS midclavicular (MCL) line and 4th ICS anterior axillary line (AAL) on both sides of the thorax using computed tomography (CT) in 139 children in three different age groups (0, 5, 10 years). RESULTS: Width of the intercostal space was significantly smaller at the 4th ICS compared to the 2nd ICS in all age groups on both sides of the thorax. Chest wall thickness was marginally smaller at the 4th ICS compared to the 2nd ICS in infants and significantly smaller at 4th ICS in children aged 5 years and 10 years. Depth to vital structure for correct angle of needle entry was smaller at the 4th ICS in all age groups on both sides of the thorax. Incorrect angle of needle entry however is accompanied by a higher risk of injury at 2nd ICS. Furthermore, in some children aged 0 and 5 years, the heart or the thymus gland were found directly adjacent to the thoracic wall at 2nd ICS midclavicular line. CONCLUSION: Especially in small children risk of iatrogenic injury to vital structures by needle decompression is considerably high. The 4th ICS AAL offers a smaller chest wall thickness, but the width of the ICS is smaller and the risk of injury to the intercostal vessels and nerve is greater. Deviations from correct angle of entry however are accompanied by higher risk of injury to intrathoracic structures at the 2nd ICS. Furthermore, we found the heart and the thymus gland to be directly adjacent to the thoracic wall at the 2nd ICS MCL in a few children. From our point of view this puncture site can therefore not be recommended for decompression in small children. We therefore recommend 4th ICS AAL as the primary site of choice.
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Descompresión Quirúrgica/métodos , Servicios Médicos de Urgencia/métodos , Agujas , Neumotórax/cirugía , Pared Torácica/diagnóstico por imagen , Toracostomía/métodos , Tomografía Computarizada por Rayos X/métodos , Adulto , Niño , Preescolar , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Neumotórax/diagnósticoRESUMEN
INTRODUCTION: Quantitative computed tomography (qCT) is an emergent technique for diagnostics and research in patients with chronic obstructive pulmonary disease (COPD). qCT parameters demonstrate a correlation with pulmonary function tests and symptoms. However, qCT only provides anatomical, not functional, information. We evaluated five distinct, partial-machine learning-based mathematical models to predict lung function parameters from qCT values in comparison with pulmonary function tests. METHODS: 75 patients with diagnosed COPD underwent body plethysmography and a dose-optimized qCT examination on a third-generation, dual-source CT with inspiration and expiration. Delta values (inspiration-expiration) were calculated afterwards. Four parameters were quantified: mean lung density, lung volume low-attenuated volume, and full width at half maximum. Five models were evaluated for best prediction: average prediction, median prediction, k-nearest neighbours (kNN), gradient boosting, and multilayer perceptron. RESULTS: The lowest mean relative error (MRE) was calculated for the kNN model with 16%. Similar low MREs were found for polynomial regression as well as gradient boosting-based prediction. Other models led to higher MREs and thereby worse predictive performance. Beyond the sole MRE, distinct differences in prediction performance, dependent on the initial dataset (expiration, inspiration, delta), were found. CONCLUSION: Different, partially machine learning-based models allow the prediction of lung function values from static qCT parameters within a reasonable margin of error. Therefore, qCT parameters may contain more information than we currently utilize and can potentially augment standard functional lung testing.
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BACKGROUND: For neonates and children requiring decompression of tension pneumothorax, specific recommendations for the choice of needle type and size are missing. The aim of this retrospective study was to determine optimal length and diameter of needles for decompression of tension pneumothorax in paediatric patients. METHODS: Utilizing computed tomography, we determined optimal length and diameter of needles to enable successful decompression and at the same time minimize risk of injury to intrathoracic structures and the intercostal vessels and nerve. Preexisting computed tomography scans of the chest were reviewed in children aged 0, 5 and 10 years. Chest wall thickness and width of the intercostal space were measured at the 4th intercostal space at the anterior axillary line (AAL) on both sides of the thorax. In each age group, three needles different in bore and length were evaluated regarding sufficient length for decompression and risk of injury to intrathoracic organs and the intercostal vessels and nerve. RESULTS: 197 CT-scans were reviewed, of which 58 were excluded, resulting in a study population of 139 children and 278 measurements. Width of the intercostal space was small at 4th ICS AAL (0 years: 0.44 ± 0.13 cm; 5 years: 0.78 ± 0.22 cm; 10 years: 1.12 ± 0.36 cm). The ratio of decompression failure to risk of injury at 4th ICS AAL was most favourable for a 22G/2.5 cm catheter in infants (Decompression failure: right: 2%, left: 4%, Risk of injury: right: 14%, left: 24%), a 22G/2.5 cm or a 20G/3.2 cm catheter in 5-year-old children (20G/3.2 cm: Decompression failure: right: 2.1%, left: 0%, Risk of injury: right: 2.1%, left: 17%) and a 18G/4.5 cm needle in 10-year-old children (Decompression failure: right: 9.5%, left: 9.5%, Risk of injury: right: 7.1%, left: 11.9%). CONCLUSIONS: In children aged 0, 5 and 10 years presenting with a tension pneumothorax, we recommend 22G/2.5 cm, 20G/3.2 cm and 18G/4.5 cm needles, respectively, for acute decompression.
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Descompresión Quirúrgica/instrumentación , Agujas , Neumotórax/diagnóstico por imagen , Neumotórax/cirugía , Niño , Preescolar , Toma de Decisiones Clínicas , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos , Costillas/diagnóstico por imagen , Pared Torácica/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
OBJECTIVES: To assess the occurrence of transient interruption of contrast (TIC) phenomenon in pulmonary computed tomography angiography (CTPA) exams performed in inspiratory breath-hold after patients were told to inspire gently. METHODS: In this retrospective single-centre study, CTPA exams of 225 consecutive patients scanned on a 16-slice CT scanner system were analysed. A-priori to measurements, exams were screened for inadequate pulmonary artery contrast due to incorrect bolus tracking or failure of i.v. contrast administration. Those exams were excluded. Attenuation values in the thoracic aorta and in the pulmonary trunk were assessed in duplicate measurements (M1 and M2) and the aorto-pulmonary density ratio was calculated. An aorto-pulmonary ratio > 1 with still contrast inflow being visible within the superior vena cava was defined as TIC. RESULTS: 3 patients were excluded due to incorrect bolus tracking. Final analysis was performed in 222 patients (mean age 65 ± 19 years, range 18 to 99 years). Mean density in the pulmonary trunk was 275±17 HU, in the aorta 208 ± 15 HU. Mean aorto-pulmonary ratio was 0.81± 0.29. 48 patients (21.6%) had an aorto-pulmonary ratio >1. Correlation of mean aorto-pulmonary ratio and age was: -0.213 (p = 0.001). Age was not significantly different for an aorto-pulmonary ratio >1 vs. ≤1 (p = 0.122). Both in M1 and M2, 33/222 patients presented with absolute HU values of < 200 HU within the pulmonary artery. In M1 measurements, 24 of these 33 patients (72%) fulfilled TIC criteria (M2: 25/33 patients (75%)). CONCLUSIONS: TIC is a common phenomenon in CTPA studies with inspiratory breath-hold commands after patients were told to inspire gently with an incidence of 22% in our retrospective cohort. Occurrence of TIC shows a significant negative correlation with increasing age and disproportionately often occurs in patients with lower absolute contrast density values within their pulmonary arteries.
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Contencion de la Respiración , Angiografía por Tomografía Computarizada/métodos , Arteria Pulmonar/diagnóstico por imagen , Embolia Pulmonar/diagnóstico por imagen , Vena Cava Superior/diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Angiografía por Tomografía Computarizada/estadística & datos numéricos , Medios de Contraste , Femenino , Humanos , Incidencia , Inhalación , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Adulto JovenRESUMEN
BACKGROUND: Although left atrial appendage (LAA) anatomy and topographic relations are well understood, little is known about the impairment of neighboring structures (NBS) by an implanted left atrial appendage closure (LAAC) device. This prospective longitudinal observational study for the first time describes distances of implanted LAA closure (LAAC) devices to NBS using a standardized imaging protocol of cardiac computed tomography angiography (cCTA). HYPOTHESIS: cCTA imaging is an eligible tool for post-implantation evaluation of LAAC devices and their relation to neighboring structures. METHODS: cCTA data sets of consecutive patients 6 months after successful LAAC were acquired on a third generation dual-source CT system and reconstructed with a slice thickness of 0.5 mm. The standardized multi-planar reconstruction LAA occluder view for post-implantation evaluation (LOVE) algorithm was used to measure the distances to NBS in relation to LAA morphology and implanted LAAC devices. RESULTS: A total of 48 patients (median age 80 years, 25% female) were included. Left upper pulmonary vein and circumflex artery were generally closest to occlusion devices (median 2.9 and 2.8 mm, respectively). AMPLATZER AMULET devices were closer to the mitral valve annulus than WATCHMAN devices (6.6 mm (inter quartile range [IQR] 4.9-8.6) vs 10.9 mm (IQR 7.4-14.0), P = 0.001). Distances to the left upper pulmonary vein were affected by LAA morphology, with cauliflower type having the closest proximity (1.7 mm [IQR 1.0-3.4], P = 0.048). CONCLUSION: A standardized cCTA imaging protocol is an eligible tool to accurately measure distances to NBS. Left upper pulmonary vein and circumflex artery are closest to LAAC devices and could thus be most prone to impairment.