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1.
J Comput Assist Tomogr ; 44(2): 289-294, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32195809

RESUMEN

OBJECTIVE: The purpose of this study was to quantify the reduction in radiation dose achievable by using the optimal z-axis coverage in coronary computed tomography (CT) angiography (CCTA) on a latest-generation 256-slice scanner. METHODS: A total of 408 scans were reviewed that were performed on a wide-range detector scanner allowing up to 16-cm z-axis coverage (adjustable in 2-cm increments). For each CCTA study, we assessed the radiation dose (ie, dose-length product and volume CT dose index) and measured the minimum z-axis coverage necessary to cover the complete cardiac anatomy. We calculated the potential radiation dose savings achievable through reduction of the z-axis coverage to the minimum necessary. RESULTS: The majority of the CCTA scans were performed with a z-axis coverage of 16 cm (n = 285, 69.9%), followed by 14 cm (n = 121, 29.7%) and 12 cm (n = 2, 0.5%). In the group that was scanned with a collimation of 16 cm, radiation dose could have been reduced by 12.5% in 55 patients, 25% in 195 patients, and 37.5% in 33 patients when using optimal z-axis coverage for CCTA. In the group that was scanned with a collimation of 14 cm, radiation dose could have been reduced by 14.3% in 90 patients, and 28.6% in 30 patients, whereas in the group that was scanned with a collimation of 12 cm, dose could have been reduced by 16.7% in 2 patients. CONCLUSIONS: Using correct z-axis coverage in CCTA on a latest-generation 256-slice scanner yields average dose reductions of 22.0% but may be as high as 37.5%.


Asunto(s)
Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Dosis de Radiación , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Estudios Retrospectivos
2.
Medicine (Baltimore) ; 99(9): e19297, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32118745

RESUMEN

To evaluate the utility of echocardiography (echo) in the diagnosis of persistent fifth aortic arch (PFAA), a very rare congenital aortic arch anomaly, and to compare echo and computed tomography angiography (CTA) imaging findings to improve our understanding of this anomaly.Data on the clinical diagnosis, imaging findings, and clinical management of PFAA were retrospectively analyzed in 10 suspected cases of PFAA admitted to our hospital between January 2012 and February 2017. We compared echo as a first line examination modality, and CTA and surgery results as the gold standard. Weinberg's classification was used to classify the type of PFAA.All patients (100%) received echo examination, eight patients (80%) received CTA examination, and four patients (40%) received sternotomy surgery; all recovered well after surgery. According to Weinberg's classification, 2, 6, and 2 cases (20%, 60%, and 20%) were classified as Type A, B, and C, respectively. Echo was able to diagnose 5 cases of PFAA (1 Type A case and 4 Type B cases) in the first instance. The diagnostic conformance rate of echo was 62.5% after comparisons with CTA and surgery results.The clinical manifestation of PFAA was atypical, and its diagnosis depended primarily on medical imaging. Echo has a relatively high diagnostic accuracy for PFAA, which is very valuable for its early detection.


Asunto(s)
Coartación Aórtica/diagnóstico , Angiografía por Tomografía Computarizada/normas , Ecocardiografía/normas , Coartación Aórtica/fisiopatología , Niño , Preescolar , Angiografía por Tomografía Computarizada/métodos , Angiografía por Tomografía Computarizada/estadística & datos numéricos , Ecocardiografía/métodos , Ecocardiografía/estadística & datos numéricos , Femenino , Humanos , Lactante , Recién Nacido , Masculino , Estudios Retrospectivos
3.
Medicine (Baltimore) ; 99(2): e18069, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31914012

RESUMEN

This study aims to find and locate foramens exactly in maxilla and mandible in case of complications during surgeries.Computer topographic angiography (CTA) images of 120 cases were reviewed. The measurements were performed on coronal, sagittal and axial planes after the 3 dimension volume reconstruction. The distances among foramens, bony landmarks, teeth, and facial artery were all measured with the angles as adjustments.The incisive foramen (IF) was measured 20.55 ±â€Š2.81 mm to margo inferior of incisor, and 45.27 ±â€Š5.27 degree from the axial midline. The greater palatine foramen located 43.17 ±â€Š2.55 mm from the IF, while 21.08 ±â€Š3.75 degree from the midline in axial plane. The lesser palatine foramina located 44.56 ±â€Š5.74 mm from the IF and 20.05 ±â€Š3.59 degree to the midline. The Mandibular foramen (MBF) was 91.15 ±â€Š1.86 mm horizontally to the margo inferior of incisor. The angle that the MBF-margo inferior of incisor line made with the axial midline was 31.25 ±â€Š2.89 degree. The shortest horizontal distance from the mental foramen (MF) to the facial artery in sagittal plane was 21.90 ±â€Š1.86 mm, while it became 13.00 ±â€Š2.05 mm in coronary section. The horizontal distance from the MF to the margo inferior of incisor in sagittal plane was 22.04 ±â€Š3.22 mm. It turned out to be 25.78 ±â€Š5.23 mm between MF and mid-sagittal line in coronary section. The vertical distance was 25.20 ±â€Š3.06 mm from the upper margin of the second premolar to the MF.The foramens were clearly seen through CTA. Moreover, linear and angular measurements were presented, which makes it safer and wiser for surgeons to consider the biometric data before operations.


Asunto(s)
Puntos Anatómicos de Referencia/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Mandíbula/anatomía & histología , /diagnóstico por imagen , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Arterias , Huesos/diagnóstico por imagen , Huesos/cirugía , Niño , Cara/irrigación sanguínea , Cara/diagnóstico por imagen , Femenino , Humanos , Incisivo/anatomía & histología , Incisivo/diagnóstico por imagen , Masculino , Mandíbula/diagnóstico por imagen , Mandíbula/patología , Mandíbula/cirugía , Persona de Mediana Edad , Adulto Joven
4.
Medicine (Baltimore) ; 99(2): e18742, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31914093

RESUMEN

To investigate the feasibility of histogram analysis with computed tomography angiography (CTA) in distinguishing between soft tissue sarcomas and benign soft tissue tumors. Fourty nine patients (23 men, mean age = 44.3 years, age range = 25-64) with pathologically-confirmed soft tissue sarcoma (n = 24) or benign soft tissue tumors (n = 25) in the lower extremities undergoing CTA for tumor evaluation were retrospectively analyzed. Two radiologists separately performed histogram analyses of CT density with CTA images by drawing a region of interest (ROI). The 10th (P10), 25th (P25), 50th (P50), 75th (P75), 90th percentiles (P90), mean, and standard deviations (SD) of measured tumor density were obtained along with measurements of the absolute value of kurtosis (AVK), absolute value of skewness (AVS), and inhomogeneity for each tumor. Intra-class correlation coefficients (ICC) were calculated to determine inter- and intra-reader variability in parameter measurements. The Mann-Whitney U test was used to compare histogram parameters between soft tissue sarcomas and benign soft tissue tumors. Receiver operator characteristic (ROC) curves were constructed to evaluate the accuracy of tumor discrimination. ICC was greater than 0.7 for AVS, AVK, and inhomogeneity, and >0.9 for mean, SD, and all percentile measures. There was no significant difference in P10, P25, P50, P75, P90, mean, or SD between soft tissue sarcomas and benign tumors (P > .05). AVS, AVK, and inhomogeneity were significantly higher in soft tissue sarcomas (P < .05). Areas under the curve (AUC) were 0.81, 0.83, and 0.84 for AVS, AVK, and inhomogeneity respectively. AUC were below 0.6 for mean, SD, and all percentiles.Skewness, kurtosis, and inhomogeneity measurements derived from histogram analysis from CTA distinguish between soft tissue sarcomas and benign soft tissue tumors.


Asunto(s)
Angiografía por Tomografía Computarizada/métodos , Neoplasias de los Tejidos Blandos/diagnóstico por imagen , Neoplasias de los Tejidos Blandos/patología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
6.
Medicine (Baltimore) ; 99(4): e18881, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31977894

RESUMEN

INTRODUCTION: Nexplanon is a 4 cm rod-shaped barium sulphate coated contraceptive implant with a usual subdermal insertion in the inner non-dominant upper arm. Complications proper to subdermal contraceptive implants are unusual and principally localized and minor, comprising infection at the site of implantation, hematoma, abnormal scar development, or local nerve and blood vessel injuries. Infrequently, contraceptive implant migration can happen, though habitually not far from the site of insertion. Pulmonary embolization of the device is remarkably rare and can present with symptoms such as chest pain or dyspnea. PATIENT CONCERNS AND DIAGNOSIS: We report one of the rare cases of asymptomatic Nexplanon pulmonary embolism in a 26-year-old female. INTERVENTIONS AND OUTCOMES: An endovascular intervention successfully retrieved the device from the lateral segment right middle lobe pulmonary artery without any complications. CONCLUSION: Several cases of contraceptive implant migration into the pulmonary artery have been reported to this day. Preventing this life-threatening complication is challenging, and yet, no clear guidelines have been established.


Asunto(s)
/administración & dosificación , Desogestrel/administración & dosificación , Implantes de Medicamentos/efectos adversos , Migración de Cuerpo Extraño/cirugía , Arteria Pulmonar/diagnóstico por imagen , Adulto , Angiografía por Tomografía Computarizada/métodos , Femenino , Migración de Cuerpo Extraño/diagnóstico por imagen , Humanos , Ultrasonografía
7.
J Comput Assist Tomogr ; 44(1): 7-12, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31939875

RESUMEN

OBJECTIVE: The aim of the study was to investigate the feasibility of coronary computed tomography (CT) angiography with a low kilovoltage peak scan and a refined scan timing prediction using a small contrast medium (CM) dose. METHODS: In protocol A, 120-kVp scanning and a standard CM dose were used. The scan timing was fixed. In protocol B, 80 kVp and a 60% CM dose were used. The scan timing was determined according to the interval from the CM arrival to the peak time in the ascending aorta. We measured the CT number and recorded the radiation dose. RESULTS: Higher CT numbers were observed in the left circumflex (proximal, P = 0.0235; middle, P = 0.0007; distal, P < 0.0001) in protocol B compared with protocol A. The radiation dose in protocol B was significantly lower than in protocol A (2.2 ± 0.9 vs 4.3 ± 1.7 mSv). CONCLUSIONS: Low-contrast, low-radiation dose, high-image quality coronary CT angiography can be performed with low kilovoltage peak scanning and a refined scan timing prediction.


Asunto(s)
Angiografía por Tomografía Computarizada/métodos , Medios de Contraste/administración & dosificación , Enfermedad de la Arteria Coronaria/diagnóstico por imagen , Intensificación de Imagen Radiográfica/métodos , Anciano , Cálculo de Dosificación de Drogas , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dosis de Radiación , Estudios Retrospectivos
8.
J Comput Assist Tomogr ; 44(1): 13-19, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31939876

RESUMEN

OBJECTIVE: To evaluate image quality and radiation dose exposure of low-kV setting and low-volume contrast medium (CM) computed tomography angiography (CTA) protocol for transcatheter aortic valve implantation (TAVI) planning in comparison with standard CTA protocol. METHODS: Sixty-patients were examined with 256-row MDCT for TAVI planning: 32 patients (study group) were evaluated using 80-kV electrocardiogram-gated protocol with 60 mL of CM and IMR reconstruction; 28 patients underwent a standard electrocardiogram-gated CTA study (100 kV; 80 mL of CM; iDose4 reconstruction). Subjective and objective image quality was evaluated in each patient at different aortic levels. Finally, we collected radiation dose exposure data (CT dose index and dose-length product) of both groups. RESULTS: In study protocol, significant higher mean attenuation values were achieved in all measurements compared with the standard protocol. There were no significant differences in the subjective image quality evaluation in both groups. Mean dose-length product of study group was 56% lower than in the control one (P < 0.0001). CONCLUSION: Low-kV and low-CM volume CTA, combined with IMR, allows to correctly performing TAVI planning with high-quality images and significant radiation dose reduction compared with standard CTA protocol.


Asunto(s)
Estenosis de la Válvula Aórtica/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Medios de Contraste/administración & dosificación , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Adulto , Anciano , Anciano de 80 o más Años , Algoritmos , Estenosis de la Válvula Aórtica/cirugía , Femenino , Humanos , Bases del Conocimiento , Masculino , Persona de Mediana Edad , Tomografía Computarizada Multidetector , Periodo Preoperatorio , Dosis de Radiación , Reemplazo de la Válvula Aórtica Transcatéter
9.
J Comput Assist Tomogr ; 44(1): 20-25, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31939877

RESUMEN

OBJECTIVES: The purpose of this study was to evaluate whether quantitative analysis of lower leg muscle enhancement measured from dynamic computed tomographic angiography (dyn-CTA) could be used for diagnosis of peripheral arterial occlusive disease. METHODS: Patients (N = 35) with known peripheral arterial occlusive disease underwent the dyn-CTA of calves first. Five minutes later, standard CTA of the peripheral runoff from the diaphragm to the toes was performed. A runoff score was assigned by radiologists as a reference standard for each of 4 lower leg artery segments. The lower leg muscle enhancement measured from the dyn-CTA was analyzed by using quantitative kinetic parameters, including initial enhancement (E1), peak enhancement (Epeak), and enhancement ratio (ER) calculated from average time attenuation curves. In addition, histogram of lower leg muscle enhancement was evaluated by using the first enhanced phase images. RESULTS: Lower extremities were diagnosed as a normal group (n = 22) with each vessel segment score equals to 1 or lower and runoff score, 7 or lower, and otherwise as an ischemia group (n = 48). Average ± SD E1 is 91.4% ± 8.5% and 82.3% ± 10.7%, Epeak is 122.7% ± 10.4% and 115.6% ± 11.1%, and ER is 0.75 ± 0.05 and 0.72 ± 0.09 for normal and ischemia group, respectively. Statistical analysis showed that average E1 and Epeak for the ischemia group were significantly lower (P < 0.05) than the normal group. The histogram analysis demonstrated that mean and median of muscle enhancement in the ischemia group were significantly smaller (P < 0.05), and coefficient of variation (CV) was significantly larger (P < 0.05) than the normal group. There were weak negative correlations (r = -0.42, P < 0.05) between runoff scores and E1 and Epeak, and weak positive correlation (r = 0.40, P < 0.05) between runoff scores and CV. The receiver operating characteristics analysis between the 2 groups had area under the curve of 0.77 and 0.76 for E1 and CV, respectively. CONCLUSIONS: Lower leg muscle enhancement measured from the dyn-CTA could be assessed quantitatively to assist diagnosis of ischemia in clinical practice.


Asunto(s)
Arteriopatías Oclusivas/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Extremidad Inferior/diagnóstico por imagen , Músculo Esquelético/diagnóstico por imagen , Enfermedad Arterial Periférica/diagnóstico por imagen , Adulto , Anciano , Estudios de Factibilidad , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dosis de Radiación
10.
J Comput Assist Tomogr ; 44(1): 32-36, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31939879

RESUMEN

OBJECTIVE: To evaluate the effect of ultra high-resolution computed tomography (UHRCT) and model-based iterative reconstruction (MBIR) on the detectability of simulated submillimeter artery. METHODS: A small vessel phantom ranging from 0.4 to 2.0 mm in diameter and edge phantoms of low to high attenuation values were scanned by UHRCT (super-high-resolution mode and normal-resolution-mode) and conventional CT, and data were reconstructed by MBIR and filtered back projection (FBP). Vessel detectability was assessed subjectively and the effective size at which 50% of response was achieved (ES50 [mm]) was calculated. Modulation transfer function (MTF) was calculated by an edge spread function method. RESULTS: ES50 of super high-resolution mode (0.36 mm for MBIR and 0.50 mm for FBP) was significantly smaller than those of normal-resolution mode (P < 0.01). In the MTF analysis, the MTF of MBIR improved as the edge phantom attenuation increased, whereas that of FBP was stable. CONCLUSIONS: Both UHRCT and MBIR are effective for the detectability of simulated submillimeter artery.


Asunto(s)
Angiografía por Tomografía Computarizada/métodos , Vasos Coronarios/diagnóstico por imagen , Algoritmos , Humanos , Fantasmas de Imagen , Dosis de Radiación , Interpretación de Imagen Radiográfica Asistida por Computador
11.
J Comput Assist Tomogr ; 44(1): 37-42, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31939880

RESUMEN

OBJECTIVE: The purpose of this study was to determine whether computed tomography (CT) angiography with machine learning (ML) can be used to predict the rapid growth of abdominal aortic aneurysm (AAA). MATERIALS AND METHODS: This retrospective study was approved by our institutional review board. Fifty consecutive patients (45 men, 5 women, 73.5 years) with small AAA (38.5 ± 6.2 mm) had undergone CT angiography. To be included, patients required at least 2 CT scans a minimum of 6 months apart. Abdominal aortic aneurysm growth, estimated by change per year, was compared between patients with baseline infrarenal aortic minor axis. For each axial image, major axis of AAA, minor axis of AAA, major axis of lumen without intraluminal thrombi (ILT), minor axis of lumen without ILT, AAA area, lumen area without ILT, ILT area, maximum ILT area, and maximum ILT thickness were measured. We developed a prediction model using an ML method (to predict expansion >4 mm/y) and calculated the area under the receiver operating characteristic curve of this model via 10-fold cross-validation. RESULTS: The median aneurysm expansion was 3.0 mm/y. Major axis of AAA and AAA area correlated significantly with future AAA expansion (r = 0.472, 0.416 all P < 0.01). Machine learning and major axis of AAA were a strong predictor of significant AAA expansion (>4 mm/y) (area under the receiver operating characteristic curve were 0.86 and 0.78). CONCLUSIONS: Machine learning is an effective method for the prediction of expansion risk of AAA. Abdominal aortic aneurysm area and major axis of AAA are the important factors to reflect AAA expansion.


Asunto(s)
Aneurisma de la Aorta Abdominal/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Interpretación de Imagen Radiográfica Asistida por Computador/métodos , Anciano , Anciano de 80 o más Años , Progresión de la Enfermedad , Femenino , Humanos , Aprendizaje Automático , Masculino , Estudios Retrospectivos
12.
J Comput Assist Tomogr ; 44(1): 153-159, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31939897

RESUMEN

OBJECTIVE: The aim of this study was to assess the utility of 70-kilovoltage-peak (kVp) contrast-enhanced computed tomography (CECT) for visualization and identification of the right adrenal vein (RAV) in comparison with that of conventional 120-kVp CECT. METHODS: This retrospective study included patients who underwent adrenal venous sampling with concurrent biphasic 120-kVp (120-kVp group, n = 43) or 70-kVp (70-kVp group, n = 47) CECT. Signal-to-noise ratios, contrast-to-noise ratios, longitudinal lengths, conspicuity scores, RAV detection rates, and size-specific dose estimates were compared between the 2 groups. RESULTS: In comparison with the 120-kVp group, the 70-kVp group had significantly higher signal-to-noise and contrast-to-noise ratios (P < 0.001-P = 0.033), greater longitudinal lengths (P < 0.001-P = 0.002), superior conspicuity scores for the RAV (P < 0.001), higher RAV detection rates (P = 0.015-P = 0.033), and lower size-specific dose estimates (P < 0.001). CONCLUSIONS: Seventy-kilovoltage-peak CECT has advantages over conventional 120-kVp CECT and is potentially useful for noninvasive assessment of the precise anatomy of the RAV.


Asunto(s)
Glándulas Suprarrenales/irrigación sanguínea , Angiografía por Tomografía Computarizada/métodos , Hiperaldosteronismo/diagnóstico por imagen , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Dosis de Radiación , Estudios Retrospectivos , Sensibilidad y Especificidad , Relación Señal-Ruido
13.
Radiol Med ; 125(2): 137-144, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31659676

RESUMEN

OBJECTIVES: To retrospectively compare semi-qualitative and quantitative CT pulmonary angiography (CTPAs) image metrics testing diagnostic performance between protocols performed by 20 or 40 ml of contrast medium (CM) in patients with suspected pulmonary embolism (PE). METHODS: A total of 102 CTPAs performed by 20 ml (ultra-low volume: ULV) and 74 CTPAs performed by 40 ml (low volume: LV) protocol for the diagnosis of clinically suspected PE performed between October 2012 and September 2013 were retrieved. High-concentration CM (Iomeprol 400 mgI/ml) was injected at 3 ml/s (iodine delivery rate 1.2 mgI/s). Two radiologists (blinded and independent) semi-qualitatively scored vascular enhancement and image noise according to a five-point visual scoring system. Quantitative analysis was performed by regions of interest quantifying densitometric parameters, such as central and peripheral pulmonary arteries vascular contrast enhancement (CE, threshold for diagnostic CE ≥ 250 HU), and metrics for image noise. Continuous variables were compared by the Student's t test between groups if normally distributed while categorical variables were analyzed with the Chi-squared test. Interobserver agreement was calculated by the weighted kappa test; correlation coefficients were calculated using Pearson's correlation tests. RESULTS: The semi-qualitative scores for central and peripheral pulmonary arteries vascular CE were sufficient by ULV, yet inferior than LV (p < 0.001). Semi-qualitative image noise was comparable between ULV and LV, and the interobserver agreement was only fair for quality of peripheral vessels. Agreement on nondiagnostic semi-qualitative parameters was seen in 9/102 (8.8%) ULV CTPAs, in particular associated with massive PE (2/9), pleuro-pulmonary abnormalities (5/9) or without major abnormalities (2/9). Quantitative analysis showed that mean CE was lower in ULV group (p < 0.001), though greater than the diagnostic threshold of 250 HU in both groups. CONCLUSIONS: Diagnostic vascular CE (> 250 HU) was obtained in both 20 ml and 40 ml CTPAs. CTPA by 20 ml of CM rendered diagnostic CE for the assessment of pulmonary arteries in patients with clinical suspicion of acute PE. Decreased image quality was mostly associated with massive PE or concomitant pleuro-parenchymal abnormalities.


Asunto(s)
Protocolos Clínicos , Angiografía por Tomografía Computarizada/métodos , Medios de Contraste/administración & dosificación , Servicio de Urgencia en Hospital , Yopamidol/análogos & derivados , Embolia Pulmonar/diagnóstico por imagen , Anciano , Femenino , Humanos , Yopamidol/administración & dosificación , Masculino , Estudios Retrospectivos
14.
Br J Radiol ; 93(1106): 20190701, 2020 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-31825655

RESUMEN

OBJECTIVE: To evaluate accuracy of virtual-non-contrast images (VNC) compared to true-unenhanced-images (TNC) for evaluation of liver attenuation acquired using spectral-detector CT (SDCT). METHODS: 149 patients who underwent multiphase transcatheter-aortic-valve-replacement (TAVR) SDCT-examinations [unenhanced-chest (TNC), CT-angiography chest (CTA-chest, early arterial-phase) and abdomen (CTA-abdomen, additional early arterial-phase after a second injection of contrast media)] were retrospectively included. VNC of CTA-chest (VNC-chest) and CTA-abdomen (VNC-abdomen) were reconstructed and compared to TNC. Region of interest-based measurement of mean attenuation (Hounsfield unit, HU) was applied in the following regions: liver, spleen, abdominal aorta and paraspinal muscle. RESULTS: VNC accuracy was high in the liver, spleen, abdominal aorta and muscle for abdomen-scanning. For the liver, average attenuation was 59.0 ± 9.1 HU for TNC and 72.6 ± 9.5 HU for CTA-abdomen. Liver attenuation in VNC-abdomen (59.1 ± 6.4 HU) was not significantly different from attenuation in TNC (p > 0.05). In contrast, VNC was less accurate for chest-scanning: Due to the protocol, in CTA-chest no contrast media was present in the liver parenchyma as indicated by the same attenuation in TNC (59.0 ± 9.1 HU) and CTA-chest (58.8 ± 8.9 HU, p > 0.05). Liver attenuation in VNC-chest (56.2 ± 6.4 HU, p < 0.05) was, however, significantly lower than in TNC and CTA-chest implying an artificial reduction of attenuation. CONCLUSION: VNC performed well in a large cohort of TAVR-examinations yielding equivalent mean attenuations to TNC; however, application of this technique might be limited when no or very little contrast media is present in parenchyma, more precisely in an early arterial-phase of the liver. ADVANCES IN KNOWLEDGE: This study showed that VNC can be reliably applied in cardiac protocols when certain limitations are considered.


Asunto(s)
Hígado/diagnóstico por imagen , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Abdomen , Anciano , Anciano de 80 o más Años , Angiografía por Tomografía Computarizada/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos , Tórax , Realidad Virtual
15.
J Stroke Cerebrovasc Dis ; 29(1): 104493, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31734123

RESUMEN

OBJECTIVE: The aim of this study was to investigate the value of extracranial carotid artery calcium score in predicting severity of carotid arterial stenosis. MATERIAL AND METHODS: 200 patients who had indication of contrast neck multi detector computed tomography were included. Calcium volume score of each calcified plaque (density more than 130 HU) was determined by multiplying area of calcified plaque in slice increment and presented as cubic centimeter (cc). Calcium score of each side (right or left) and each patient were determined. Severity of carotid stenosis in axial images was estimated and categorized. Statistical analysis was performed. RESULTS: 87 cases were female with mean age of 58.90 ± 10.67 and 113 cases were male with mean age of 59.61 ± 11.89 years old. The mean of volume score for all evaluated 800 vessels was .079 ± .046 cc. There was no significant difference between calcium score of right and left side (P value = .16). The mean "patient score" was .080 ± .049 cc (range: 0-.15 cc).Nine patients had volume score of 0 and all of them had no evidence of luminal stenosis. Significant increase in severity of stenosis was seen with increase in "patient score".(P value < .001, r = .875).According to receiver operating characteristic analysis, "patient score" of .09 cc with sensitivity of 97% and "patient score" of .12 cc with sensitivity of 95% can predict 50% and 70% stenosis, respectively. CONCLUSIONS: Promising role of calcium score for predicting severity of carotid stenosis could be considered.


Asunto(s)
Arterias Carótidas/diagnóstico por imagen , Estenosis Carotídea/diagnóstico por imagen , Angiografía por Tomografía Computarizada/métodos , Tomografía Computarizada Multidetector , Calcificación Vascular/diagnóstico por imagen , Anciano , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Pronóstico , Reproducibilidad de los Resultados , Índice de Severidad de la Enfermedad
16.
Radiol Med ; 125(2): 117-127, 2020 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-31686317

RESUMEN

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.


Asunto(s)
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 Termoluminiscente
18.
Radiol Med ; 125(3): 265-271, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31863358

RESUMEN

PURPOSE: To investigate whether the increased obstruction of the pulmonary arteries was associated with reduced pulmonary vein areas in acute pulmonary embolism (APE). METHOD: We retrospectively analyzed a consecutive series of computed tomography pulmonary angiography studies of 107 patients with APE and 101 controls without APE between November 2010 and January 2019. The control and patient groups were compared with each other for differences between the mean cross-sectional areas of pulmonary veins. Further analysis was conducted by dividing the patient group into high-risk patients (≥ 20%) and low-risk patients (< 20%) according to the pulmonary arterial obstruction index. The mean cross-sectional area of the pulmonary veins in these two groups was compared. RESULTS: The mean cross-sectional areas of the 4 pulmonary veins at the ostium level (CSAPV) were significantly lower for the patient group (mean: 102.6 mm2) compared with the control group (111.8 mm2) (p < 0.001). CSAPV cutoff value for determining the diagnosis of APE that maximized the accuracy was 109.12 mm2 (AUC = 0.721; 95% CI 0.649-0.794); its sensitivity and specificity were 78.2% and 69.2%, respectively. CSAPV cutoff value for differentiating high-risk APE that maximized the accuracy was 102.6 mm2 (AUC = 0.634; 95% CI 0.525-0.743); its sensitivity and specificity were 61.9% and 53.8%, respectively. CONCLUSIONS: There is a negative correlation between the CSAPV and thrombotic material burden in the pulmonary arteries of patients with APE. Hence, the CSAPV can be used as a diagnostic tool in the evaluation of the presence and severity of pulmonary embolism.


Asunto(s)
Arteria Pulmonar/diagnóstico por imagen , Embolia Pulmonar/diagnóstico por imagen , Venas Pulmonares/diagnóstico por imagen , Trombosis/diagnóstico por imagen , Enfermedad Aguda , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Angiografía por Tomografía Computarizada/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Curva ROC , Estudios Retrospectivos , Sensibilidad y Especificidad , Adulto Joven
19.
J Comput Assist Tomogr ; 44(1): 1-6, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-31855880

RESUMEN

OBJECTIVES: To investigate the coronary venous system (CVS) and its spatial relationship with coronary arteries by using 256-slice computed tomography (CT). METHODS: One hundred one patients underwent coronary CT angiography by using a 256-slice CT. In each patient, the CVS and its spatial relationship with coronary arteries were analyzed. We measured the diameters and angulations of the coronary sinus (CS), great cardiac vein, anterior interventricular vein (AIV), left marginal vein, posterior vein of the left ventricle (PVLV), and posterior interventricular vein (PIV), and the distances, respectively, from the CS ostium and from the crossing point to the ostium of corresponding tributaries. RESULTS: The following 5 pairs of veins and arteries had a higher frequency of intersecting compared with others: the CS/great cardiac vein and the left circumflex coronary artery (97.1%), the AIV and the diagonal or ramus branch (92.1%), the PIV and the posterior branch of left ventricle artery (88.1%), the left marginal vein and the circumflex or circumflex marginal (73.9%), and the PVLV and the circumflex or circumflex marginal (31.6%). The other 2 pairs had a higher frequency of running parallel to each other: the AIV and the left anterior descending artery (76.2%) and the PIV and the posterior descending artery (54.4%). Most tributaries were lateral to their corresponding arteries at the crossing point except for the AIV. For the PVLV and PIV, the distances from the crossing point to the ostium of corresponding veins when the veins were lateral to the arteries were smaller than those when the veins were medial to the arteries (P < 0.05). CONCLUSIONS: The CVS and its anatomical relationship with the coronary arterial system can be examined with details by using a 256-slice CT, which has important clinical implications.


Asunto(s)
Enfermedades Cardiovasculares/diagnóstico por imagen , Angiografía por Tomografía Computarizada/instrumentación , Vasos Coronarios/diagnóstico por imagen , Adulto , Anciano , Anciano de 80 o más Años , Angiografía por Tomografía Computarizada/métodos , Enfermedad de la Arteria Coronaria , Vasos Coronarios/anatomía & histología , Femenino , Humanos , Procesamiento de Imagen Asistida por Computador/métodos , Masculino , Persona de Mediana Edad , Estudios Retrospectivos
20.
Br J Radiol ; 93(1105): 20190003, 2020 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-31738082

RESUMEN

OBJECTIVE: This study aimed to assess and compare the diagnostic performance of the coronary artery to aortic luminal attenuation ratio (CAR), transluminal attenuation gradient (TAG), and corrected coronary opacification (CCO) difference on coronary CT angiography (cCTA) for detecting haemodynamically significant coronary artery stenosis. METHODS: 33 patients who underwent cCTA, gated SPECT myocardial perfusion imaging (MPI), and invasive coronary angiography within 3 months were included in this retrospective study. The degree of coronary stenosis on cCTA was visually assessed in all patients. Additionally, CAR, TAG, and CCO difference were analyzed and calculated in all patients. Haemodynamically significant coronary stenosis was defined as a vessel with ≥50% luminal stenosis on invasive coronary angiography and an associated abnormal perfusion defect on MPI in the same territory. Diagnostic performance was assessed on a per-vessel basis by the area under the receiver operating characteristic (ROC) curve (AUC). RESULTS: Among 99 vessels, 12 were excluded and the remaining 87 were analyzed. 17 (19.5%) vessels were determined as haemodynamically significant coronary artery stenosis. On ROC analysis, the AUC was 0.71 for cCTA, 0.80 for CAR, 0.61 for TAG, 0.74 for CCO, 0.87 for combined CAR and cCTA, 0.77 for combined TAG and cCTA, and 0.75 for combined CCO and cCTA. The AUC for combined CAR and cCTA was significantly greater compared with cCTA alone (p < 0.01). CONCLUSION: Non-invasive CAR derived from 64-detector row CT was feasible and might be helpful for the detection of haemodynamically significant coronary artery stenosis. Still, further investigations such as intra- and inter-reader correlation, evaluation of larger numbers in different settings, and time efficiency are required for applying CAR in various situations. ADVANCES IN KNOWLEDGE: CAR could be used as novel noninvasive technique to detect haemodynamically significant coronary artery stenosis.


Asunto(s)
Angiografía por Tomografía Computarizada/métodos , Angiografía Coronaria/métodos , Estenosis Coronaria/diagnóstico por imagen , Anciano , Aorta Torácica/diagnóstico por imagen , Estenosis Coronaria/fisiopatología , Femenino , Hemodinámica , Humanos , Masculino , Interpretación de Imagen Radiográfica Asistida por Computador , Estudios Retrospectivos , Tomografía Computarizada de Emisión de Fotón Único
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