RESUMEN
The application of cardiac magnetic resonance (CMR) imaging in clinical practice has grown due to technological advancements and expanded clinical indications, highlighting its superior capabilities when compared to echocardiography for the assessment of myocardial tissue. Similarly, the utilization of implantable cardiac electronic devices (CIEDs) has significantly increased in cardiac arrhythmia management, and the requirements of CMR examinations in patients with CIEDs has become more common. However, this type of exam often presents challenges due to safety concerns and image artifacts. Until a few years ago, the presence of CIED was considered an absolute contraindication to CMR. To address these challenges, various technical improvements in CIED technology, like the reduction of the ferromagnetic components, and in CMR examinations, such as the introduction of new sequences, have been developed. Moreover, a rigorous protocol involving multidisciplinary collaboration is recommended for safe CMR examinations in patients with CIEDs, emphasizing risk assessment, careful monitoring during CMR, and post-scan device evaluation. Alternative methods to CMR, such as computed tomography coronary angiography with tissue characterization techniques like dual-energy and photon-counting, offer alternative potential solutions, although their diagnostic accuracy and availability do limit their use. Despite technological advancements, close collaboration and specialized staff training remain crucial for obtaining safe diagnostic CMR images in patients with CIEDs, thus justifying the presence of specialized centers that are equipped to handle these type of exams.
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Desfibriladores Implantables , Imagen por Resonancia Magnética , Marcapaso Artificial , Humanos , Desfibriladores Implantables/normas , Imagen por Resonancia Magnética/métodos , Imagen por Resonancia Magnética/instrumentación , Arritmias Cardíacas/diagnóstico por imagenRESUMEN
Mitral regurgitation (MR) is a broadly diffuse valvular heart disease (VHD) with a significant impact on the healthcare system and patient prognosis. Transcatheter mitral valve interventions (TMVI) are now well-established techniques included in the therapeutic armamentarium for managing patients with mitral regurgitation, either primary or functional MR. Even if the guidelines give indications regarding the correct management of this VHD, the wide heterogeneity of patients' clinical backgrounds and valvular and heart anatomies make each patient a unique case, in which the appropriate device's selection requires a multimodal imaging evaluation and a multidisciplinary discussion. Proper pre-procedural evaluation plays a pivotal role in judging the feasibility of TMVI, while a cooperative work between imagers and interventionalist is also crucial for procedural success. This manuscript aims to provide an exhaustive overview of the main parameters that need to be evaluated for appropriate device selection, pre-procedural planning, intra-procedural guidance and post-operative assessment in the setting of TMVI. In addition, it tries to give some insights about future perspectives for structural cardiovascular imaging.
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Cateterismo Cardíaco , Implantación de Prótesis de Válvulas Cardíacas , Insuficiencia de la Válvula Mitral , Válvula Mitral , Imagen Multimodal , Humanos , Insuficiencia de la Válvula Mitral/cirugía , Insuficiencia de la Válvula Mitral/diagnóstico por imagen , Imagen Multimodal/métodos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Implantación de Prótesis de Válvulas Cardíacas/instrumentación , Implantación de Prótesis de Válvulas Cardíacas/normas , Válvula Mitral/cirugía , Válvula Mitral/diagnóstico por imagen , Cateterismo Cardíaco/métodos , Cateterismo Cardíaco/instrumentaciónRESUMEN
Background and Objectives: Cardiac magnetic resonance (CMR) imaging has become an essential instrument in the study of cardiomyopathies; it has recently been integrated into the diagnostic workflow for cardiac amyloidosis (CA) with remarkable results. An additional emerging role is the stratification of the arrhythmogenic risk by scar analysis and the possibility of merging these data with electro-anatomical maps. This is made possible by using a software (ADAS 3D, Galgo Medical, Barcelona, Spain) able to provide 3D heart models by detecting fibrosis along the whole thickness of the myocardial walls. Little is known regarding the applications of this software in the wide spectrum of cardiomyopathies and the potential benefits have yet to be discovered. In this study, we tried to apply the ADAS 3D in the context of CA. Materials and Methods: This study was a retrospectively analysis of consecutive CMR imaging of patients affected by CA that were treated in our center (Marche University Hospital). Wherever possible, the data were processed with the ADAS 3D software and analyzed for a correlation between the morphometric parameters and follow-up events. The outcome was a composite of all-cause mortality, unplanned cardiovascular hospitalizations, sustained ventricular arrhythmias (VAs), permanent reduction in left ventricular ejection fraction, and pacemaker implantation. The secondary outcomes were the need for a pacemaker implantation and sustained VAs. Results: A total of 14 patients were deemed eligible for the software analysis: 8 patients with wild type transthyretin CA, 5 with light chain CA, and 1 with transthyretin hereditary CA. The vast majority of imaging features was not related to the composite outcome, but atrial wall thickening displayed a significant association with both the primary (p = 0.003) and the secondary outcome of pacemaker implantation (p = 0.003). The software was able to differentiate between core zones and border zones of scars, with the latter being the most extensively represented in all patients. Interestingly, in a huge percentage of CMR images, the software identified the highest degree of core zone fibrosis among the epicardial layers and, in those patients, we found a higher incidence of the primary outcome, without reaching statistical significance (p = 0.18). Channels were found in the scar zones in a substantial percentage of patients without a clear correlation with follow-up events. Conclusions: CMR imaging plays a pivotal role in cardiovascular diagnostics. Our analysis shows the feasibility and applicability of such instrument for all types of CA. We could not only differentiate between different layers of scars, but we were also able to identify the presence of fibrosis channels among the different scar zones. None of the data derived from the ADAS 3D software seemed to be related to cardiac events in the follow-up, but this might be imputable to the restricted number of patients enrolled in the study.
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Amiloidosis , Cardiomiopatías , Cicatriz , Imagen por Resonancia Magnética , Humanos , Masculino , Proyectos Piloto , Femenino , Cardiomiopatías/diagnóstico por imagen , Amiloidosis/diagnóstico por imagen , Amiloidosis/complicaciones , Anciano , Cicatriz/diagnóstico por imagen , Estudios Retrospectivos , Persona de Mediana Edad , Imagen por Resonancia Magnética/métodos , Programas InformáticosRESUMEN
A cardiac lesion detected at ultrasonography might turn out to be a normal structure, a benign tumor or rarely a malignancy, and lesion characterization is very important to appropriately manage the lesion itself. The exact relationship of the mass with coronary arteries and the knowledge of possible concomitant coronary artery disease are necessary preoperative information. Moreover, the increasingly performed coronary CT angiography to evaluate non-invasively coronary artery disease leads to a rising number of incidental findings. Therefore, CT and MRI are frequently performed imaging modalities when echocardiography is deemed insufficient to evaluate a lesion. A brief comprehensive overview about diagnostic radiological imaging and the clinical background of cardiac masses and pseudomasses is reported.
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Enfermedad de la Arteria Coronaria , Humanos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Tomografía Computarizada por Rayos X , Angiografía por Tomografía Computarizada , Angiografía CoronariaRESUMEN
Non-invasive cardiovascular imaging owns a pivotal role in the preoperative assessment of patient candidates for transcatheter aortic valve implantation (TAVI), providing a wide range of crucial information to select the patients who will benefit the most and have the procedure done safely. This document has been developed by a joined group of experts of the Italian Society of Cardiology and the Italian Society of Medical and Interventional Radiology and aims to produce an updated consensus statement about the pre-procedural imaging assessment in candidate patients for TAVI intervention. The writing committee consisted of members and experts of both societies who worked jointly to develop a more integrated approach in the field of cardiac and vascular radiology. Part 2 of the document will cover CT and MR angiography, standard medical reporting, and future perspectives.
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Estenosis de la Válvula Aórtica , Cardiología , Reemplazo de la Válvula Aórtica Transcatéter , Angiografía , Válvula Aórtica/diagnóstico por imagen , Válvula Aórtica/cirugía , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Estenosis de la Válvula Aórtica/cirugía , Humanos , Tomografía Computarizada por Rayos X/métodos , Reemplazo de la Válvula Aórtica Transcatéter/métodosRESUMEN
BACKGROUND: Cardiac MRI plays a critical role in the management of thalassemic patients. No accurate biventricular reference values are available. PURPOSE: To establish the ranges for normal left ventricular (LV) and right ventricular (RV) volumes and ejection fraction (EF) and LV mass normalized to body surface area (BSA), age, and gender in a large cohort of well-treated beta-thalassemia major (ß-TM) patients without heart damage using a multiparametric MRI. STUDY TYPE: Retrospective/cohort study. POPULATION: In all, 251 ß-TM patients with no known risk factors or cardiac disease, normal electrocardiogram, no macroscopic myocardial fibrosis, and all cardiac segments with T2 * ≥20 msec, and 246 healthy subjects. FIELD STRENGTH/SEQUENCE: 1.5T/cine steady-state free precession (SSFP), gradient-echo T2 *, late gadolinium enhancement (LGE) images. ASSESSMENT: Biventricular end-diastolic volume, end-systolic volume, stroke volume, and LV mass were normalized to BSA (EDVI, ESVI, SVI). STATISTICAL TESTS: Comparisons between the two groups was performed with two-samples t-test or Wilcoxon's signed rank test. For more than two groups, one-way analysis of variance (ANOVA) or a Kruskal-Wallis test were applied. RESULTS: Compared to controls, males with ß-TM showed significantlt higher LVEDVI in all the age groups, while for the other volumes the difference was significant only within one or more age groups. In females the volumes were comparable between ß-TM patients and healthy subjects in all the age groups. In the male ß-TM population we found a significant effect of age on LVEDVI (P = 0.017), LVESVI (P = 0.001), RVESVI (P = 0.029), and RVEF (P = 0.031), while for females none of the biventricular parameters were significantly different among the age groups (LVEDVI: P = 0.614; LVESVI: P = 0.449; LVSVI: P = 0.186; LV mass index: P = 0.071; LVEF: P = 0.059; RVEDVI: P = 0.374; RVESVI: P = 0.180; RVSVI: P = 0.206; RVEF: P = 0.057). In ß-TM patients all biventricular volume indexes as well as the LV mass index were significantly larger in males than in females (P < 0.0001 in all cases). The LV and the RV EF were comparable between the sexes (P = 0.568 and P = 0.268, respectively). DATA CONCLUSION: Appropriate "normal" reference ranges normalized to BSA, sex, and age are recommended to avoid misdiagnosis of cardiomyopathy in ß-TM patients. LEVEL OF EVIDENCE: 4 TECHNICAL EFFICACY STAGE: 2.
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Lesiones Cardíacas , Talasemia beta , Superficie Corporal , Estudios de Cohortes , Medios de Contraste , Femenino , Gadolinio , Ventrículos Cardíacos/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Masculino , Valores de Referencia , Estudios Retrospectivos , Volumen Sistólico , Función Ventricular Izquierda , Talasemia beta/diagnóstico por imagenRESUMEN
Computed tomography coronary angiography (CTCA) has become a cornerstone in the diagnostic process of the heart disease. Although the cardiac imaging with interventional procedures is responsible for approximately 40% of the cumulative effective dose in medical imaging, a relevant radiation dose reduction over the last decade was obtained, with the beginning of the sub-mSv era in CTCA. The main technical basis to obtain a radiation dose reduction in CTCA is the use of a low tube voltage, the adoption of a prospective electrocardiogram-triggering spiral protocol and the application of the tube current modulation with the iterative reconstruction technique. Nevertheless, CTCA examinations are characterized by a wide range of radiation doses between different radiology departments. Moreover, the dose exposure in CTCA is extremely important because the benefit-risk calculus in comparison with other modalities also depends on it. Finally, because anatomical evaluation not adequately predicts the hemodynamic relevance of coronary stenosis, a low radiation dose in routine CTCA would allow the greatest use of the myocardial CT perfusion, fractional flow reserve-CT, dual-energy CT and artificial intelligence, to shift focus from morphological assessment to a comprehensive morphological and functional evaluation of the stenosis. Therefore, the aim of this work is to summarize the correct use of the technical basis in order that CTCA becomes an established examination for assessment of the coronary artery disease with low radiation dose.
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Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Dosis de Radiación , Exposición a la Radiación/prevención & control , Factores de Edad , Algoritmos , Inteligencia Artificial , Índice de Masa Corporal , Angiografía por Tomografía Computarizada/instrumentación , Circulación Coronaria , Femenino , Reserva del Flujo Fraccional Miocárdico , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Medición de Riesgo , Factores Sexuales , Factores de TiempoRESUMEN
BACKGROUND: As one of the most frequent risk factors for cardiovascular disease, type 2 diabetes mellitus (T2DM) is one of the largest causes of death. However, an acute cardiac presentation is not uncommon in diabetic patients, and the current investigative approach remains often inadequate. The aim of our study was to retrospectively stratify the risk of asymptomatic T2DM patients using low-dose 640-slice coronary computed tomography angiography (CCTA). MATERIALS AND METHODS: CCTA examinations of 62 patients (mean age, 65 years) with previous diagnosis of type 2 diabetes and without cardiac symptoms were analyzed. Image acquisition was performed using a 640-slice CT. Per-patient, per-vessel and per-plaque analyses were performed. Stratification risk was evaluated according to the ESC guidelines. The patients were followed up after 2.21 ± 0.56 years from CCTA examination. RESULTS: Coronary artery disease (CAD) was found in 58 patients (93.55%) presenting 290 plaques. Analysis of all samples showed severe-to-occlusive atherosclerosis in 24 patients (38.7% of cases). However, over the degree of stenosis, 23 patients were evaluated at high risk considering the extension of CAD. Good agreement was shown by the correlation of CAD extension/risk estimation and MACE incidence, according to a Kaplan-Meier survival analysis (p value = 0.001), with a 7.25-fold increased risk (HR 7.25 CI 2.13-24.7; p value = 0.002). CONCLUSION: Our study confirms the high capability of CCTA to properly stratify the CV risk of asymptomatic T2DM patients. Its use could be recommended if we consider how current investigative strategies to correctly assess these patients often seem inadequate.
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Enfermedades Asintomáticas , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Diabetes Mellitus Tipo 2/complicaciones , Placa Aterosclerótica/diagnóstico por imagen , Anciano , Angiografía por Tomografía Computarizada , Enfermedad de la Arteria Coronaria/etiología , Estenosis Coronaria/diagnóstico por imagen , Femenino , Humanos , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Tomografía Computarizada Multidetector/métodos , Placa Aterosclerótica/etiología , Dosis de Radiación , Estudios Retrospectivos , Medición de RiesgoRESUMEN
PURPOSE: To compare measured radiation dose (MD), estimated radiation dose (ED) and image quality in coronary computed tomography between turbo-flash (TFP) and retrospective protocol (RP) and correlate MD with size-specific dose estimates (SSDE). MATERIALS AND METHODS: In this prospective study, we selected 68 patients (mean age, 59.2 ± 9.7 years) undergoing 192 × 2 dual-source CT (SOMATOM Force, Siemens) to rule out coronary artery disease. Thirty-one underwent TFP and 37 RP. To evaluate in vivo MD, thermoluminescent dosimeters were placed, superficially, at thyroid and heart level, left breast areola and left hemi-thorax. MD in each site, and ED parameters, such as volume CT dose index (CTDIvol), SSDE, dose length product (DLP), effective dose (E), were compared between two protocols with a t test. Image quality was compared between two protocols. Inter-observer agreement was evaluated with a kappa coefficient (k). In each protocol, MD was correlated with SSDE using a Pearson coefficient (r). RESULTS: Comparing TFP and RP, MD at thyroid (1.43 vs. 2.58 mGy; p = 0.0408), heart (3.58 vs. 28.72 mGy; p < 0.0001), left breast areola (3.00 vs. 24.21 mGy; p < 0.0001) and left hemi-thorax (2.68 vs. 24.03 mGy; p < 0.0001), CTDIvol, SSDE, DLP and E were significantly lower. Differences in image quality were not statistically significant. Inter-observer agreement was good (k = 0.796) in TFP and very good (k = 0.817) in RP. MD and SSDE excellently correlated with TFP (r = 0.9298, p < 0.0001) and RP (r = 0.9753, p < 0.0001). CONCLUSIONS: With TFP, MD, CTDIvol, SSDE, DLP and E were significantly lower, than with RP. Image quality was similar between two protocols. MD correlated excellently with SSDE in each protocol.
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Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Dosis de Radiación , Medios de Contraste , Femenino , Humanos , Yopamidol , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Interpretación de Imagen Radiográfica Asistida por Computador , Dosimetría TermoluminiscenteRESUMEN
Over the past few years, the approach to the 'arrhythmic patient' has profoundly changed. An early clinical presentation of arrhythmia is often accompanied by non-specific symptoms and followed by inconclusive electrocardiographic findings. In this scenario, cardiac magnetic resonance (CMR) has been established as a clinical tool of fundamental importance for a correct prognostic stratification of the arrhythmic patient. This technique provides a high-spatial-resolution tomographic evaluation of the heart, which allows studying accurately the ventricular volumes, identifying even segmental kinetic anomalies and properly detecting diffuse or focal tissue alterations through an excellent tissue characterization, while depicting different patterns of fibrosis distribution, myocardial edema or fatty substitution. Through these capabilities, CMR has a pivotal role for the adequate management of the arrhythmic patient, allowing the identification of those phenotypic manifestations characteristic of structural heart diseases. Therefore, CMR provides valuable information to reclassify the patient within the wide spectrum of potentially arrhythmogenic heart diseases, the definition of which remains the major determinants for both an adequate treatment and a poor prognosis. The purpose of this review study was to focus on the role of CMR in the evaluation of the main cardiac clinical entities associated with arrhythmogenic phenomena and to present a brief debate on the main pathophysiological mechanisms involved in the arrhythmogenesis process.
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Arritmias Cardíacas/diagnóstico por imagen , Técnicas de Imagen Cardíaca/métodos , Cardiomiopatías/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Arritmias Cardíacas/etiología , Arritmias Cardíacas/fisiopatología , Cardiomegalia Inducida por el Ejercicio , Cardiomiopatías/complicaciones , Cardiomiopatías/fisiopatología , Diagnóstico Diferencial , Ecocardiografía/métodos , Electrocardiografía , Fibrosis Endomiocárdica/complicaciones , Fibrosis Endomiocárdica/diagnóstico por imagen , Humanos , Prolapso de la Válvula Mitral/complicaciones , Prolapso de la Válvula Mitral/diagnóstico por imagenRESUMEN
OBJECTIVES: To assess the transferability of the magnetic resonance imaging (MRI) multislice multiecho T2* technique for pancreatic iron overload assessment. METHODS: Multiecho T2* sequences were installed on ten 1.5-T MRI scanners of the three main vendors. Five healthy subjects (n = 50) were scanned at each site. Five patients with thalassemia (n = 45) were scanned locally at each site and were rescanned at the reference site within 1 month. T2* images were analyzed using a previously validated software and the global pancreatic T2* value was calculated as the mean of T2* values over the head, body, and tail. RESULTS: T2* values of healthy subjects were above 26 ms and showed inter-site homogeneity. The T2* values measured in the MRI sites were comparable to the correspondent values observed in the reference site (12.02 ± 10.20 ms vs 11.98 ± 10.47 ms; p = 0.808), and the correlation coefficient was 0.978 (p < 0.0001). Coefficients of variation (CoVs) ranged from 4.22 to 9.77%, and the CoV for all the T2* values independently from the sites was 8.55%. The intraclass correlation coefficient (ICC) for each MRI site was always excellent and the global ICC was 0.995, independently from the sites. The mean absolute difference in patients with pancreatic iron (n = 39) was -0.15 ± 1.38 ms. CONCLUSION: The gradient-echo T2* MRI technique is an accurate and reproducible means for the quantification of pancreatic iron and may be transferred among MRI scanners by different vendors in several centers. KEY POINTS: ⢠The gradient-echo T2* MRI technique is an accurate and reproducible means for the quantification of pancreatic iron. ⢠The gradient-echo T2* MRI technique for the quantification of pancreatic iron may be transferred among MRI scanners by different vendors in several centers. ⢠Pancreatic iron might serve as an early predictor of cardiac siderosis and is the strongest overall predictor of glucose dysregulation.
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Hierro/metabolismo , Imagen por Resonancia Magnética/métodos , Páncreas/patología , Siderosis/diagnóstico , Adulto , Femenino , Humanos , Masculino , Páncreas/metabolismo , Reproducibilidad de los Resultados , Siderosis/metabolismoRESUMEN
AIM: To provide an overview on dose reduction and image quality after the installation of a third-generation dual-source CT (dsCT) in a Pediatric Radiology Department. MATERIALS AND METHODS: We included pediatric patients (< 20 years old) undergoing CT for oncological staging (neck, chest and abdomen) or low-dose chest CT for lung diseases. Each of these two groups were further divided in two age groups (≤ or > 10 years old) including patients scanned in the same period of two consecutive years, in 2017 with a 16-row LightSpeed CT (GE Healthcare) or in 2018 with a Somatom Force dsCT (Siemens Healthineers). Technical parameters such as kVp, mAs, slice thickness, exposure times and dose indicators were retrieved and compared. Image quality was evaluated in consensus by two radiologists on a five-point semiquantitative scale. Nonparametric tests were used. RESULTS: In oncological patients, significantly lower kVp and tube current with better image quality were achieved with the dsCT. Radiation dose (total DLP) was 5-6 times lower with dsCT, thanks also to virtual non-contrast images. In low-dose chest CT, the frequent use of tin filter required higher tube current; a total DLP 3 times lower was achieved with dsCT in patients ≤ 10 years old. The image quality was better with the dsCT in low-dose chest CT protocols. CONCLUSION: The third-generation dsCT provides high-quality images with reduced motion artifacts at lower dose.
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Enfermedades Pulmonares/diagnóstico por imagen , Tomografía Computarizada Multidetector/normas , Tomografía Computarizada Multidetector/tendencias , Neoplasias/diagnóstico por imagen , Dosis de Radiación , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Adolescente , Factores de Edad , Artefactos , Niño , Femenino , Humanos , Masculino , Tomografía Computarizada Multidetector/instrumentación , Movimientos de los Órganos , Imagen Radiográfica por Emisión de Doble Fotón/instrumentación , Radiografía Torácica/normas , Radiografía Torácica/tendencias , Adulto JovenRESUMEN
PURPOSE: To compare radiation exposure associated with daily practice cardiovascular (CV) examinations performed on two different multidetector computed tomography (MDCT) scanners, a conventional 64-MDCT and a third-generation dual-source (DS) MDCT. MATERIALS AND METHODS: In this retrospective study, 1458 patients who underwent CV examinations between January 2017 and August 2018 were enrolled. A single-source 64-MDCT (Lightspeed VCT, GE) scan was performed in 705 patients from January to August 2017 (207 coronary examinations and 498 vascular examinations) and 753 patients underwent third-generation 192 × 2-DSCT (Somatom FORCE, Siemens) scan from January to August 2018 (302 coronary examinations and 451 vascular examinations). Volume CT dose index (CTDIvol), dose length product (DLP), effective dose (ED), tube voltage (TV) and exposure time (ET), pitch factor (PF) were registered for each patient. Student's t test was used to compare mean values between each corresponding group of MDCT and DSCT. RESULTS: In coronary examinations with DSCT, CTDIvol was 24.4% lower (23.1 mGy vs 30.6 mGy, p < 0.0001) and DLP and ED reductions were 35.6% than with MDCT (465.0 mGy * cm vs 732.3 mGy * cm and 6.5 mSv and 10.3 mSv; vs p < 0.0001). Concerning scan parameters, kVp and ET reductions were 12.7% and 69.4%, respectively (p < 0.0001); PF increase was 73.8% (p < 0.0001). In all vascular studies, DSCT, compared with MDCT, permitted to reduce CTDIvol from 43.5 to 70.6%; DLP and ED reductions were from 50.3 to 73.1%; kVp and ET decreases were from 10.7 to 32.5% and from 26.3 to 68.7%. PF increase was from 16.7 to 58.1% (all differences with p < 0.0001). CONCLUSIONS: In daily practice, CV examinations CTDI, DLP, ED, ET and TV were lower and PF was higher with 192 × 2-DSCT compared to 64-MDCT.
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Enfermedades Cardiovasculares/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Tomografía Computarizada Multidetector/métodos , Exposición a la Radiación , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Angiografía por Tomografía Computarizada/efectos adversos , Angiografía por Tomografía Computarizada/instrumentación , Angiografía Coronaria/efectos adversos , Angiografía Coronaria/instrumentación , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Seguridad de Equipos , Humanos , Tomografía Computarizada Multidetector/efectos adversos , Tomografía Computarizada Multidetector/instrumentación , Dosis de Radiación , Imagen Radiográfica por Emisión de Doble Fotón/efectos adversos , Imagen Radiográfica por Emisión de Doble Fotón/instrumentación , Estudios Retrospectivos , Factores de TiempoRESUMEN
PURPOSE: To compare radiation dose and image quality of lower extremity computed tomography angiography (CTA) between cranio-caudal acquisition with single-source CT (SSCT) and flash caudo-cranial acquisition with dual-source CT (DSCT). MATERIALS AND METHODS: In this prospective study, 60 patients were randomly assigned to Group A (control) or Group B (experimental) to undergo lower extremity CTA for peripheral obliterative arterial disease. Group A received protocol 1 (P1) with SSCT cranio-caudal acquisition. Group B received protocol (P2) with DSCT flash caudo-cranial acquisition. Intravascular attenuation (IVA), signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR) and image noise were compared. Two radiologists assessed the image quality. Computed tomography volume dose index (CTDIvol) and dose-length product (DLP) were also compared. RESULTS: IVA with P2 was higher than with P1 (586.8 ± 140.3 vs. 496.1 ± 129.3 HU, p = 0.011), as was SNR (33.0 ± 11.3 vs. 27.4 ± 12.3; p = 0.042), CNR (30.1 ± 13.3 vs. 24.2 ± 10.3; p = 0.029) and image quality score of small arteries below the knee (3.8 ± 0.2 vs. 3.1 ± 0.2; p = 0.001). Radiation dose was significantly lower in P2 than in P1 with CTDIvol reduction of 40.9% (1.3 ± 0.1 vs. 2.2 ± 0.3 mGy; p = 0.006) and DLP reduction of 42.8% (148.7 ± 21.9 vs 260.2 ± 59.1 mGy * cm; p = 0.018). CONCLUSION: Lower extremity CTA with DSCT flash caudo-cranial acquisition allows lower radiation dose with higher IVA, SNR, CNR and better image quality for small arteries below the knee than SSCT cranio-caudal acquisition.
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Angiografía por Tomografía Computarizada/métodos , Extremidad Inferior/irrigación sanguínea , Extremidad Inferior/diagnóstico por imagen , Enfermedad Arterial Periférica/diagnóstico por imagen , Dosis de Radiación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Protocolos Clínicos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Relación Señal-Ruido , Método Simple Ciego , Adulto JovenRESUMEN
The physical principles of dual-energy computed tomography (DECT) are as old as computed tomography (CT) itself. To understand the strengths and the limits of this technology, a brief overview of theoretical basis of DECT will be provided. Specific attention will be focused on the interaction of X-rays with matter, on the principles of attenuation of X-rays in CT toward the intrinsic limits of conventional CT, on the material decomposition algorithms (two- and three-basis-material decomposition algorithms) and on effective Rho-Z methods. The progresses in material decomposition algorithms, in computational power of computers and in CT hardware, lead to the development of different technological solutions for DECT in clinical practice. The clinical applications of DECT are briefly reviewed in relation to the specific algorithms.
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Algoritmos , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Tecnología Radiológica/métodos , Tomografía Computarizada por Rayos X/métodos , Femenino , Humanos , Masculino , Dispersión de Radiación , Rayos XRESUMEN
Cardiovascular computer tomography (CT) in pediatric congenital heart disease (CHD) patients is often challenging. This might be due to limited patient cooperation, the high heart rate, the complexity and variety of diseases and the need for radiation dose minimization. The recent developments in CT technology with the introduction of the third-generation dual-source (DS) dual-energy (DE) CT scanners well suited to respond to these challenges. DSCT is characterized by high-pitch, long anatomic coverage and a more flexible electrocardiogram-synchronized scan. DE provides additional clinical information about vascular structures, myocardial and lung perfusion and allows artifacts reduction. These advances have increased clinical indications and modified CT protocol for pediatric CHD patients. In our hospital, DSCT with DE technology has rapidly become an important imaging technique for both pre- and postoperative management of pediatric patients with CHDs. The aim of this article is to describe the state-of-the-art in DSCT protocol with DE technology in pediatric CHD patients, providing some case examples of our experience over an 18-month period.
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Cardiopatías Congénitas/diagnóstico por imagen , Imagen Radiográfica por Emisión de Doble Fotón/métodos , Tomografía Computarizada por Rayos X/métodos , Artefactos , Niño , Preescolar , Medios de Contraste/administración & dosificación , Filtración/instrumentación , Frecuencia Cardíaca , Humanos , Lactante , Recién Nacido , Movimientos de los Órganos , Dosis de Radiación , Imagen Radiográfica por Emisión de Doble Fotón/instrumentación , Respiración , Tomografía Computarizada por Rayos X/instrumentaciónRESUMEN
INTRODUCTION: We describe the use of time-resolved imaging of contrast kinetics (TRICKS) sequence in the diagnosis of Peripheral Vascular Anomalies. In case of suspected vascular malformations time-resolved MR angiography might add important information for therapeutic decisions and follow-up. OBJECTIVE: The objective of our study was to assess the usefulness and diagnostic performance of time-resolved imaging of contrast kinetics sequence in the evaluation of peripheral vascular anomalies. SUBJECTS AND METHODS: Sixty-six patients (23 pediatric, 43 adult; mean age 26) affected by upper or lower limb vascular anomalies and studied using time-resolved imaging of contrast kinetics sequence were prospectively evaluated. All studies were performed on a 1.5-T whole-body MR system. Two independent readers tried to categorized the suspected vascular anomalies in pre-contrast and post-contrast MR sequences and assessed the overall TRICKS image quality. In 11 patients, the diagnostic performance comparability between TRICKS sequence and digital subtraction angiography was evaluated. RESULTS: On the basis of time-resolved imaging of contrast kinetics, 31 of the vascular anomalies were classified as high-flow vascular malformations, 29 as low-flow vascular lesions and 6 as hemangiomas. There was no significant difference in image quality evaluation and vascular anomaly classification between the two observers. The vascular anomalies characteristics provided by moderate, good or excellent quality TRICKS images were confirmed by digital subtraction angiography. CONCLUSION: Time-resolved imaging of contrast kinetics sequence let the radiologist to acquire useful temporal information to correctly evaluate vascular anomalies components, adding more data to those provided by conventional MR sequences, especially in case of arteriovenous malformation. Therefore, both in pediatric and adult population, TRICKS could be used as an additional initial diagnostic tool to rightly classify these lesions and evaluate if a treatment is needed and which.
Asunto(s)
Malformaciones Arteriovenosas/diagnóstico por imagen , Extremidades/irrigación sanguínea , Extremidades/diagnóstico por imagen , Aumento de la Imagen/métodos , Angiografía por Resonancia Magnética/métodos , Adolescente , Adulto , Anciano , Angiografía de Substracción Digital , Niño , Preescolar , Medios de Contraste , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Estudios ProspectivosRESUMEN
The number of patients with congenital heart disease (CHD) is rapidly increasing in the adult population, mainly due to the improved long-term survival. Serial follow-up with cardiac magnetic resonance imaging (CMR) is very appealing due to its non-invasive nature. CMR exam is able to provide specific information about cardiac function, hemodynamics, anatomy and tissue characterization unlikely achievable by other diagnostic techniques. CMR in CHD plays a role both in early diagnosis and in post-operative follow-up. Black Blood T1 weighted sequences are used to acquire morphological information. Cine Steady State Free Precession sequences are mainly used to provide data about cardiac function and kinesis. Hemodynamic assessment is routinely performed using phase contrast sequences, which provide reliable information concerning vessel flow pattern, cardiac output and intracardiac shunts. Magnetic Resonance Angiography (MRA) and 3D coronary MRA of the whole thorax can provide detailed morphological information regarding great vessels and proximal coronary arteries. Presence of late gadolinium enhancement suggesting myocardial macroscopic fibrosis seems to play a prognostic and diagnostic role even in this field.
Asunto(s)
Cardiopatías Congénitas/diagnóstico , Angiografía por Resonancia Magnética , Imagen por Resonancia Cinemagnética , Niño , Medios de Contraste/administración & dosificación , Diagnóstico Diferencial , Diagnóstico Precoz , Estudios de Seguimiento , Gadolinio/administración & dosificación , Cardiopatías Congénitas/epidemiología , Hemodinámica , Humanos , Italia/epidemiología , Angiografía por Resonancia Magnética/métodos , Imagen por Resonancia Cinemagnética/métodos , Valor Predictivo de las Pruebas , Prevalencia , Pronóstico , Sensibilidad y Especificidad , Tetralogía de Fallot/diagnóstico , Transposición de los Grandes Vasos/diagnósticoRESUMEN
PURPOSE: The authors investigated whether contrast-enhanced cardiovascular magnetic resonance (CMR) imaging may be used to detect early cardiac involvement in patients with systemic sclerosis (SSc). MATERIALS AND METHODS: Twenty-six SSc patients (nine with diffuse cutaneous SSc and 17 with limited cutaneous SSc) and 13 sex- and age-matched healthy controls (HC) were studied. Contrast-enhanced CMR allowed the analysis of first-pass images (areas of hypo-enhancement indicating perfusion defects) and delayed images (persistent hyper-enhancement indicating fibrosis). Clinical variables including disease duration and presence of major visceral complications of SSc were investigated in each patient. RESULTS: Perfusion defects were detected in 53.8 % of SSc patients but in none of the HC. Perfusion abnormalities were detected in 28.6 % of SSc patients with disease duration less than 2 years and in 29.2 % of asymptomatic SSc patients. Delayed contrast enhancement was present in 25 % of SSc patients but not in HC. All patients with delayed contrast enhancement showed first-pass hypoperfusion. Right ventricular wall thickness was significantly increased in all SSc patients when compared to HC (p < 0.001); a similar trend was observed when SSc patients without pulmonary arterial hypertension were analysed (p < 0.04). A trend to lower end-diastolic and end-systolic right ventricular volumes in SSc versus HC was observed (p < 0.05 and p < 0.04, respectively). CONCLUSIONS: Myocardial hypoperfusion is common in SSc and occurs early in the course of the disease. Co-localisation of perfusion defects and delayed contrast enhancement indicative of fibrosis suggests that myocardial hypoxia may play a role in the pathogenesis of myocardial fibrosis.
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Cardiomiopatías/etiología , Medios de Contraste , Imagen por Resonancia Magnética/métodos , Esclerodermia Sistémica/complicaciones , Adolescente , Adulto , Anciano , Cardiomiopatías/diagnóstico , Sistema Cardiovascular/fisiopatología , Electrocardiografía , Femenino , Fibrosis , Humanos , Masculino , Persona de Mediana Edad , Esclerodermia Difusa/complicacionesRESUMEN
Congenital absence of the pericardium (CAP) is an unusual condition discovered, in most cases, incidentally but can potentially lead to fatal complications, including severe arrhythmias and sudden death. Recently, the use of modern imaging technologies has increased the diagnosis of CAP, providing important findings for risk stratification. Nevertheless, there is not yet consensus regarding therapeutic decisions, and the management of patients with CAP remains challenging. In this paper, we discuss the pathophysiological implication of CAP, review the current literature and explain the role of multimodality imaging tools for its diagnosis, management and treatment.