RESUMO
AIM: To investigate the correlation between conventional computed tomography (CT) features, quantitative texture analysis (QTA), epidermal growth factor receptor (EGFR) mutations, and survival rates in patients with lung adenocarcinoma. MATERIALS AND METHODS: Sixty-eight patients were evaluated for conventional CT features and QTA in this retrospective study. A multiple logistic regression analysis and receiver operating characteristics (ROC) curve analysis versus death and EGFR status was performed for CT features and QTA in order to assess correlation between CT features, QTA, EGFR mutations, and survival rates. A p-value <0.05 was regarded to indicate a statistically significant association. RESULTS: An EGFR mutation was identified in 26/68 tumours (38.2%). A negative association was found between EGFR mutation and emphysema (p < 0.0001) whereas a positive correlation was found with necrosis (p=0.017), air bronchogram (p=0.0304), and locoregional infiltration (p=0.0018). Mean, standard deviation, and skewness were found to have significant correlation with EGFR mutation (p=0.0001; p=0.0001; p=0.0459; Fig 3). The only parameter correlated with the event death was entropy (r=0.2708; p=0.0329). CONCLUSION: Both qualitative and quantitative analysis disclosed potential associations between CT features and QTA parameters, EGFR mutations and prognosis; these correlations need to be confirmed in larger studies to be used as imaging biomarkers in the management of patients affected by lung adenocarcinoma.
Assuntos
Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/genética , Receptores ErbB/genética , Neoplasias Pulmonares/diagnóstico por imagem , Neoplasias Pulmonares/genética , Mutação , Tomografia Computadorizada por Raios X , Adenocarcinoma/mortalidade , Adenocarcinoma de Pulmão , Idoso , Feminino , Humanos , Neoplasias Pulmonares/mortalidade , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Taxa de SobrevidaRESUMO
AIM: To evaluate image quality and diagnostic accuracy of different dual-energy computed tomography (DECT) datasets for identification of hepatocellular carcinoma (HCC), assess the reliability of virtual unenhanced (VU) images in replacing standard unenhanced (SU) images, and quantify effective dose (ED) at different tube voltages. MATERIAL AND METHODS: Thirty cirrhotic patients underwent liver contrast-enhanced DECT. Two blinded observers retrospectively evaluated conventional unenhanced and VU images, 140 kVp/80 kVp/mixed tube potential arterial datasets and conventional portal-venous/late phases in consensus. Final diagnosis was based on pathological proof or imaging criteria. Image quality, ED, sensitivity, and specificity of arterial datasets were calculated. RESULTS: Thirty-eight HCC and 18 benign lesions were detected at 80 kVp, 33 HCC and 22 benign lesions were detected at 140 kVp, and 36 HCC and 20 benign lesions were detected at mixed tube potentials. Final diagnosis confirmed 37 HCC and 20 benign lesions. There was no significant difference in diagnostic confidence between 80 kVp, 140 kVp, and mixed tube potential arterial datasets (p>0.05). Image quality was adequate for all datasets, with increased quality at higher tube potential (80 versus 140 kVp, p=0.001; mixed versus 140 kVp, p=0.001; 80 kVp versus mixed, p=0.0024). Significant ED reduction was observed between 140 and 80 kVp datasets (p<0.001). CONCLUSIONS: The 140 kVp dataset provided higher image quality. The 80 kVp images were more sensitive in detecting HCC. VU images are adequate in replacing SU images. The ED of the 80 kVp dataset was significantly lower.
Assuntos
Carcinoma Hepatocelular/diagnóstico por imagem , Neoplasias Hepáticas/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Meios de Contraste , Feminino , Humanos , Imageamento Tridimensional , Iopamidol/análogos & derivados , Masculino , Pessoa de Meia-Idade , Doses de Radiação , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e EspecificidadeRESUMO
PURPOSE: This study was undertaken to prospectively evaluate the diagnostic performance of colour Doppler ultrasonography (CDUS), first-pass (FP) and steady-state (SS) contrast-enhanced magnetic resonance angiography (MRA) and computed tomography angiography (CTA) of the carotid arteries using digital subtraction angiography (DSA) as the reference standard. MATERIALS AND METHODS: A total of 170 patients with previous cerebrovascular events and suspected carotid artery stenoses underwent CDUS, blood-pool MRA, CTA and DSA. Accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for CDUS, FP MRA, SS MRA and CTA. The McNemar and Wilcoxon tests and receiver operating characteristic (ROC) curve analysis were used to determine significant differences (p<0.05) between the diagnostic performances of the four modalities, and the degree of stenosis was compared using linear regression. RESULTS: A total of 336 carotid bifurcations were studied. The area under the curve (AUC) for degree of stenosis was: CDUS 0.85±0.02, FP MRA 0.982±0.005, SS MRA 0.994±0.002 and CTA 0.997±0.001. AUC analysis showed no statistically significant difference between CTA and MRA (p=0.0174) and a statistically significant difference between CDUS and the other techniques (p<0.001). Plaque morphology analysis showed no significant difference between CTA and SS MRA; a significant difference was seen between CTA and SS MRA versus FP MRA (p=0.04) and CDUS (p=0.038). Plaque ulceration analysis showed a statistically significant difference between MRA and CTA (0.04< p<0.046) versus CDUS (p=0.019). CONCLUSIONS: CTA is the most accurate technique for evaluating carotid stenoses, with a slightly better performance than MRA (97% vs. 95% for SS MRA and 92% for FP MRA) and a greater accuracy than CDUS (97% vs. 76%). Blood-pool contrast-enhanced SS sequences offer improved evaluation of degree of stenosis and plaque morphology with accuracy substantially identical to CTA.
Assuntos
Angiografia/métodos , Estenose das Carótidas/diagnóstico , Angiografia por Ressonância Magnética/métodos , Tomografia Computadorizada por Raios X/métodos , Ultrassonografia Doppler em Cores/métodos , Idoso , Idoso de 80 Anos ou mais , Angiografia Digital , Área Sob a Curva , Estenose das Carótidas/diagnóstico por imagem , Meios de Contraste , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Prospectivos , Curva ROC , Sensibilidade e Especificidade , Estatísticas não ParamétricasRESUMO
AIM: To assess the accuracy of low-dose contrast-enhanced time-resolved 3T magnetic resonance angiography (MRA) for the morphological and functional assessment of vascular malformations (VM), and to evaluate its diagnostic potential for the depiction of treatment-induced changes. MATERIALS AND METHODS: Twenty-five patients with known VM underwent MRA to evaluate the location and extent of lesions and their haemodynamic characteristics. Three-dimensional (3D) T1-weighted time-resolved sequences were acquired following the administration of 0.05mmol/kg of gadobenate dimeglumine. VM were classified according to their morphology and haemodynamic characteristics. All patients thereafter underwent conventional angiography to confirm the diagnosis and to treat the lesions (embolization or sclerotherapy). Follow-up MRA was performed 30 days after treatment to assess morphological and functional changes. A visual analogue scale (VAS) was used to clinically assess the severity of symptoms before and after therapy. RESULTS: Based on haemodynamic characteristics, VM were classified as predominantly arterial [4 (16%)], artero-venous [19 (76%)] or venous [2 (8%)]. Twenty-three (92%) lesions were classified as high-flow VM and two (8%) as low-flow VM. Intralesional thrombosis was present in 17 (68%) lesions before therapy and in 10 lesions (40%) after therapy. The median VAS scores were 5±1 before treatment and 4±2 after treatment. Very good correlation (Spearman's correlation coefficient: rho=0.87; p=0.000) was noted between the reduction of lesion size on follow-up MRA and pain relief as assessed by VAS. CONCLUSION: Low-dose contrast-enhanced time-resolved 3T MRA can be used to define morphological and functional aspects of VM accurately during treatment planning and follow-up, and can identify post-therapy changes that positively correlate with treatment outcome.
Assuntos
Meios de Contraste , Embolização Terapêutica/métodos , Angiografia por Ressonância Magnética/métodos , Meglumina/análogos & derivados , Compostos Organometálicos , Malformações Vasculares/diagnóstico , Adolescente , Adulto , Criança , Feminino , Humanos , Aumento da Imagem , Imageamento Tridimensional , Masculino , Pessoa de Meia-Idade , Medição da Dor , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Malformações Vasculares/fisiopatologia , Malformações Vasculares/terapia , Adulto JovemRESUMO
PURPOSE: The authors performed a preliminary study with blood-pool contrast-enhanced magnetic resonance angiography (MRA) in evaluating the degree of carotid artery stenosis and plaque morphology, comparing the diagnostic performance of first-pass (FP) and steady-state (SS) acquisitions with 64-slice computed tomography angiography (CTA) and using digital subtraction angiography (DSA) as the reference standard. MATERIALS AND METHODS: Twenty patients with >or=50% carotid artery stenosis at Doppler sonography underwent blood-pool contrast-enhanced MRA, CTA and DSA. Two independent radiologists evaluated MRA and CTA examinations to assess the degree of stenosis and characterise plaque morphology. Accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were calculated for FP, SS and CTA. The McNemar and Wilcoxon tests were used to determine significant differences (p<0.05) between the diagnostic performance of the three modalities. RESULTS: Forty carotid bifurcations were studied. For stenosis grading, accuracy, sensitivity, specificity, PPV and NPV were 90%, 89%, 90%, 89% and 90%, respectively, at FP; 95%, 95%, 95%, 95% and 95%, respectively, at SS; and 97.5%, 95%, 100%, 100% and 95%, respectively, at CTA. SS and CTA were superior to FP for evaluating the degree of stenosis (p<0.05). For evaluating plaque morphology, accuracy, sensitivity, specificity, PPV and NPV were 87.5%, 89%, 86%, 85% and 90%, respectively, at FP; 97.5%, 100%, 95%, 95% and 100%, respectively, at SS; and 100%, 100%, 100%, 100% and 100%, respectively, at CTA. There were no significant differences between FP, SS and CTA for plaque assessment (p>0.05). CONCLUSIONS: Blood-pool contrast-enhanced MRA with SS sequences allow improved diagnostic evaluation of the degree of carotid stenosis and plaque morphology compared with FP and is substantially equal to CTA and DSA.
Assuntos
Estenose das Carótidas/diagnóstico por imagem , Meios de Contraste , Gadolínio , Angiografia por Ressonância Magnética , Compostos Organometálicos , Angiografia/métodos , Angiografia Digital , Estenose das Carótidas/patologia , Humanos , Tomografia Computadorizada por Raios XRESUMO
PURPOSE: This study was undertaken to compare the accuracy of magnetic resonance (MR) imaging and 64-slice multidetector computed tomography (64-MDCT) in the T staging of gastric carcinoma in comparison with histopathology. MATERIALS AND METHODS: Forty patients with an endoscopic diagnosis of gastric carcinoma underwent preoperative MR imaging and 64-MDCT, both of which were performed after i.v. injection of scopolamine and water distension of the stomach. In the MR imaging protocol, we acquired T2-weighted turbo spin-echo (TSE) sequences, true fast imaging steady-state free precession (true-FISP) and gadolinium-enhanced T1-weighted volumetric interpolated breath-hold examination (VIBE) 3D sequences. Contrastenhanced CT scans were obtained in the arterial and venous phases. Two groups of radiologists independently reviewed the MR and 64-MDCT images. The results were compared with pathology findings. RESULTS: In the evaluation of T stage, 64-MDCT had 82.5% and MR imaging had 80% sensitivity. Accuracy of MR imaging was slightly higher than that of 64-MDCT in identifying T1 lesions (50% vs 37.5%), whereas the accuracy of 64-MDCT was higher in differentiating T2 lesions (81.2% vs 68.7%). The accuracy of MR imaging and 64-MDCT did not differ significantly in the evaluation of T3-T4 lesions (p>0.05). Understaging was observed in 20% of cases with MR imaging and in 17.5% with 64-MDCT. CONCLUSIONS: MR imaging and 64-MDCT accuracy levels did not differ in advanced stages of disease, whereas MR imaging was superior in identifying early stages of gastric cancer and can be considered a valid alternative to MDCT in clinical practice.
Assuntos
Imageamento por Ressonância Magnética , Neoplasias Gástricas/diagnóstico por imagem , Neoplasias Gástricas/patologia , Tomografia Computadorizada por Raios X , Biópsia , Meios de Contraste , Feminino , Gastroscopia , Humanos , Masculino , Pessoa de Meia-Idade , Estadiamento de Neoplasias , Valor Preditivo dos Testes , Interpretação de Imagem Radiográfica Assistida por Computador , Estudos Retrospectivos , Sensibilidade e EspecificidadeAssuntos
Ascaríase/diagnóstico , Ascaris lumbricoides , Colo/microbiologia , Divertículo do Colo/cirurgia , Albendazol/uso terapêutico , Anastomose Cirúrgica/efeitos adversos , Animais , Antiprotozoários/uso terapêutico , Ascaríase/diagnóstico por imagem , Ascaríase/tratamento farmacológico , Colo/patologia , Endoscopia , Humanos , Itália , Masculino , Pessoa de Meia-Idade , RadiografiaRESUMO
The Authors present a rare association of gastric adenocarcinoma and somatostatin-producing duodenal carcinoid. The pre-operative abdominal CT scan revealed the gastric lesions and a duodenal polypoid lesion, giving an important indication to perform a subtotal gastrectomy and a duodenal resection. The definitive diagnosis was possible with histological examination.
Assuntos
Adenocarcinoma , Neoplasias Duodenais , Neoplasias Primárias Múltiplas , Somatostatinoma , Neoplasias Gástricas , Adenocarcinoma/diagnóstico , Adenocarcinoma/cirurgia , Idoso , Neoplasias Duodenais/diagnóstico , Neoplasias Duodenais/cirurgia , Humanos , Masculino , Neoplasias Primárias Múltiplas/diagnóstico , Neoplasias Primárias Múltiplas/cirurgia , Somatostatinoma/diagnóstico , Somatostatinoma/cirurgia , Neoplasias Gástricas/diagnóstico , Neoplasias Gástricas/cirurgiaRESUMO
AIM: Recently whole-body 3D MR angiography (MRA) with blood-pool contrast agent has become available. The purpose of this study was to introduce and evaluate this technique to demonstrate arterial steno-occlusive involvement in systemic atherosclerosis and to compare blood-pool enhanced MRA results with those of CT angiography (CTA) as reference modality. METHODS: Twenty patients with clinically and US documented carotid occlusive disease underwent whole-body MRA on a 1.5 T scanner and CTA on a 64-MDCT unit. Ten milliliters of a blood-pool agent (MS-235 Gadofosveset Trisodium, VASOVIST, Schering, Berlin, Germany) were administered intravenously and four 3-D MRA stations were acquired successively through automatic table moving. Images were reviewed by two observers. Overall image quality of each arterial segment was assessed and rated for both MRA and CTA examinations; MRA sensitivity, MRA specificity interobserver and intermodality agreement were calculated. RESULTS: Whole-body MRA with blood-pool contrast agent was well tolerated by all patients. It yielded a detailed display of the arterial system with a short examination time. In 14 out of 20 patients there was extensive involvement of the arterial bed by steno-occlusive atherosclerotic disease; for the identification and characterization of vessel damage in the various vascular districts MRA sensitivity was 92-100%, MRA specificity was 95-100%; in 2 cases MRA underestimated the degree of peripheral vessel stenosis. Interobserver agreement calculated with K value was 0.63, intermodality agreement with CTA was 93% (P<0.01). CONCLUSION: The whole-body MRA technique is a valuable tool for comprehensive evaluation of arterial steno-occlusive involvement in systemic arterial atherosclerosis; there is a good agreement between blood-pool enhanced MRA results and CTA, used as modality of reference.
Assuntos
Aterosclerose/diagnóstico , Meios de Contraste/administração & dosagem , Angiografia por Ressonância Magnética , Imagem Corporal Total/métodos , Idoso , Feminino , Humanos , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Sensibilidade e Especificidade , Tomografia Computadorizada por Raios X/métodosRESUMO
AIM: Carotid intima-media thickness (cIMT) measurements during clinical trials need to have a fixed reference point (also called as bulb edge points) in the anatomy from which the cIMT can be measured. Identification of the bulb edge points in carotid ultrasound images faces the challenge to be detected automatically due to low image quality and variations in ultrasound images, motion artefacts, image acquisition protocols, position of the patient, and orientation of the linear probe with respect to bulb and ultrasound gain controls during acquisition. METHODS: This paper presents a patented comprehensive methodology for carotid bulb localization and bulb edge detection as a reference point. The method consists of estimating the lumen-intima borders accurately using classification paradigm. Transition points are located automatically based on curvature characteristics. Further we verify and validate the locations of bulb edge points using combination of several local image processing methods such as (i) lumen-intima shapes, (ii) bulb slopes, (iii) bulb curvature, (iv) mean lumen thickness and its variations, and (v) geometric shape fitting. RESULTS: Our database consists of 155 ultrasound bulb images taken from various ultrasound machines with varying resolutions and imaging conditions. Further we run our automated system blindly to spot out the bulbs in a mixture database of 336 images consisting of bulbs and no-bulbs. We are able to detect the bulbs in the bulb database with 100% accuracy having 92% as close as to a neurologists's bulb location. Our mean lumen-intima error is 0.0133 mm with precision against the manual tracings to be 98.92%. Our bulb detection system is fast and takes on an average 9 seconds per image for detection for the bulb edge points and 4 seconds for verification/validation of the bulb edge points.
Assuntos
Artérias Carótidas , Espessura Intima-Media Carotídea/normas , Interpretação de Imagem Assistida por Computador/métodos , Algoritmos , Artérias Carótidas/anatomia & histologia , Artérias Carótidas/diagnóstico por imagem , Bases de Dados Factuais , Humanos , Valores de Referência , Reprodutibilidade dos TestesRESUMO
OBJECTIVE: To determine whether CT-perfusion (CT-p) can be used to evaluate the effects of chemotherapy and anti-angiogenic treatment in patients with non-small-cell lung carcinoma (NSCLC) and whether CT-p and standard therapeutic response assessment (RECIST) data obtained before and after therapy correlate. METHODS: 55 patients with unresectable NSCLC underwent CT-p before the beginning of therapy and 50 of them repeated CT-p 90 days after it. Therapeutic protocol included platinum-based doublets plus bevacizumab for non-squamous carcinoma and platinum-based doublets for squamous carcinoma. RECIST measurements and calculations of blood flow (BF), blood volume (BV), time to peak (TTP) and permeability surface (PS) were performed, and baseline and post-treatment measurements were tested for statistically significant differences. Baseline and follow-up perfusion parameters were also compared based on histopathological subclassification (2004 World Health Organization Classification of Tumours) and therapy response assessed by RECIST. RESULTS: Tumour histology was consistent with large cell carcinoma in 14/50 (28%) cases, adenocarcinoma in 22/50 (44%) cases and squamous cell carcinoma in the remaining 14/50 (28%) cases. BF and PS differences for all tumours between baseline and post-therapy measurements were significant (p=0.001); no significant changes were found for BV (p=0.3) and TTP (p=0.1). The highest increase of BV was demonstrated in adenocarcinoma (5.2±34.1%), whereas the highest increase of TTP was shown in large cell carcinoma (6.9±22.4%), and the highest decrease of PS was shown in squamous cell carcinoma (-21.5±18.5%). A significant difference between the three histological subtypes was demonstrated only for BV (p<0.007). On the basis of RECIST criteria, 8 (16%) patients were classified as partial response (PR), 2 (4%) as progressive disease (PD) and the remaining 40 (80%) as stable disease (SD). Among PR, a decrease of both BF (18±9.6%) and BV (12.6±9.2%) were observed; TTP increased in 3 (37.5%) cases, and PS decreased in 6 (75%) cases. SD patients showed an increase of BF, BV, TTP and PS in 6 (15%), 21 (52.5%), 23 (57.5%) and 2 (5%) cases, respectively. PD patients demonstrated an increase of BF (26±0.2%), BV (2.7±0.1%) and TTP (3.1±0.8%) while only PS decreased (23±0.2%). CONCLUSION: CT-p can adequately evaluate therapy-induced alterations in NSCLC, and perfusion parameters correlate with therapy response assessment performed with RECIST criteria. ADVANCES IN KNOWLEDGE: Evaluating perfusional parameters, CT-p can demonstrate therapy-induced changes in patients with different types of lung cancer and identify response to treatment with excellent agreement to RECIST measurements.
Assuntos
Adenocarcinoma/diagnóstico por imagem , Protocolos de Quimioterapia Combinada Antineoplásica/uso terapêutico , Carcinoma de Células Grandes/diagnóstico por imagem , Carcinoma Pulmonar de Células não Pequenas/diagnóstico por imagem , Carcinoma de Células Escamosas/diagnóstico por imagem , Neoplasias Pulmonares/diagnóstico por imagem , Adenocarcinoma/tratamento farmacológico , Idoso , Inibidores da Angiogênese/uso terapêutico , Anticorpos Monoclonais Humanizados/administração & dosagem , Bevacizumab , Carcinoma de Células Grandes/tratamento farmacológico , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Carcinoma de Células Escamosas/tratamento farmacológico , Feminino , Humanos , Neoplasias Pulmonares/tratamento farmacológico , Masculino , Pessoa de Meia-Idade , Compostos de Platina/administração & dosagem , Tomografia Computadorizada por Raios X/métodosRESUMO
Small bowel neoplasms, including adenocarcinoma, carcinoid tumour, lymphoma and gastrointestinal stromal tumours, represent a small percentage of gastrointestinal cancers, yet are among those with the poorest prognosis compared with other gastrointestinal malignancies. Unclear clinical scenarios and difficult radiological diagnosis often delay treatment with negative effects on patient survival. Recently, multidetector CT (MDCT) and MRI have been introduced as feasible and accurate diagnostic techniques for the identification and staging of small bowel neoplasms. These techniques are gradually replacing conventional barium radiography as the tool of choice. However, the inherent technical and physiological challenges of small bowel imaging require a familiarity with patient preparation and scan protocols. Adequate knowledge of the histopathology and natural evolution of small bowel neoplasms is also important for differential diagnosis. The aim of this article is to review MDCT and MRI protocols for the evaluation of small bowel tumours and to provide a concise yet comprehensive guide to the most relevant imaging features relative to histopathology.
Assuntos
Adenocarcinoma/diagnóstico , Tumor Carcinoide/diagnóstico , Neoplasias Intestinais/diagnóstico , Intestino Delgado/patologia , Linfoma não Hodgkin/diagnóstico , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Tumor Carcinoide/diagnóstico por imagem , Tumor Carcinoide/patologia , Protocolos Clínicos , Meios de Contraste , Feminino , Humanos , Neoplasias Intestinais/diagnóstico por imagem , Neoplasias Intestinais/patologia , Intestino Delgado/diagnóstico por imagem , Linfoma não Hodgkin/diagnóstico por imagem , Linfoma não Hodgkin/patologia , Imageamento por Ressonância Magnética/métodos , Masculino , Prognóstico , Tomografia Computadorizada por Raios X/métodosRESUMO
BACKGROUND AND PURPOSE: LA is a condition caused by chronic cerebral ischemia and it represents an independent risk for stroke. The purpose of this work was to determine whether CAWT studied by using MDCTA is correlated with LA and its severity. MATERIALS AND METHODS: Ninety-eight patients ≥60 years of age were retrospectively studied by using multidetector row CT. Supra-aortic vessel analysis and brain CT were performed in the same procedure. In each patient, CAWT was measured with an internal digital caliper, and the presence and severity of LA were assessed. Correlation coefficients by using Spearman statistics and ROC curves were calculated. A P value < .05 was considered statistically significant. RESULTS: Measurements of the distal common CAWT ranged from 0.5 to 1.53 mm. A correlation between LA and increased CAWT was observed (Pearson correlation, 0.33; P < .001). On the basis of a threshold of 0.9 mm, an important statistical association between increased CAWT and LA (P < .0001) was found. With the same threshold, ROC curve analysis indicated a sensitivity of 55% and a specificity of 75% for LA. CONCLUSIONS: The results of this study show a statistically significant correlation between increased CAWT and LA (and its severity).
Assuntos
Artérias Carótidas/diagnóstico por imagem , Doenças das Artérias Carótidas/complicações , Doenças das Artérias Carótidas/diagnóstico por imagem , Angiografia Cerebral/métodos , Leucoaraiose/complicações , Leucoaraiose/diagnóstico por imagem , Tomografia Computadorizada por Raios X/métodos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Reprodutibilidade dos Testes , Sensibilidade e EspecificidadeRESUMO
PURPOSE: This study was performed to validate a high-resolution whole-body magnetic resonance angiography (MRA) protocol with parallel imaging and biphasic administration of a single bolus of contrast agent in the preliminary assessment of systemic atherosclerotic burden in patients referred for endovascular procedures. MATERIALS AND METHODS: Forty patients referred for endovascular treatment of atherosclerotic disease of the carotid arteries (n=23), peripheral vessels (n=14) or aorta (n=3) on the basis of previous clinical and diagnostic examinations underwent high-resolution whole-body MRA at 1.5 T with 3D spoiled gradient recalled echo (GRE) sequences, featuring parallel imaging acquisition technique with x2 acceleration factor. Sixty-eight surface coil elements and a four-station imaging protocol were employed. Biphasic intravenous administration of a paramagnetic contrast agent [gadolinium benzyloxyproprionic-tetraacetic acid (Gd-BOPTA)] was performed with the following protocol: 10 ml at a speed of 1 ml/s followed by further 10 ml at a speed of 0.5 ml/s. For image analysis, the arterial system was divided into 42 segments for evaluation. The presence or absence of atherosclerotic lesions was evaluated by two observers in consensus; segments were classified as having clinically significant disease (>or=50% stenosis or an aneurysmal dilatation) or no significant disease (<50% stenosis). The presence of stenoocclusive disease, determined at all segments, was compared with findings on digital subtraction angiography (DSA), which were interpreted by a third independent reader. Sensitivity, specificity and concordance of whole-body MRA findings with DSA were calculated, and receiver operating characteristic (ROC) analysis was performed for all vascular territories. RESULTS: A total of 1,680 arterial segments was evaluated; 138 (8.3%) were affected by atherosclerotic alterations. Carotid lesions were confirmed in 23 patients (34 segments), involvement of peripheral vessels in 14 (57 segments) and abdominal aneurysms in three. Sensitivity and specificity of whole-body MRA were, respectively, 95%-97% for head and neck vessels, 100%-100% for thoracoabdominal vessels, 98%-97% for thigh vessels and 84%-88% for calf vessels; concordance with the DSA findings was significant (p<0.05). Subclinical atherosclerotic lesions were evidenced in 25 patients, involving carotid arteries (12 segments), peripheral vessels (21 segments) and abdominal aorta (one segment). All these lesions were confirmed by a second modality, and ten of these patients required further care. CONCLUSIONS: High-resolution whole-body MRA with Gd-BOPTA may be considered a reliable modality for imaging systemic atherosclerosis in candidates for endovascular procedures. The subclinical detection of the total atherosclerotic burden has potential implications for secondary care in this population.
Assuntos
Aterosclerose/diagnóstico , Meios de Contraste , Angiografia por Ressonância Magnética , Meglumina/análogos & derivados , Compostos Organometálicos , Procedimentos Cirúrgicos Vasculares , Imagem Corporal Total/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Aorta/patologia , Arteriopatias Oclusivas/diagnóstico , Aterosclerose/cirurgia , Estenose das Carótidas/diagnóstico , Protocolos Clínicos , Feminino , Humanos , Angiografia por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-Idade , Doenças Vasculares Periféricas/diagnóstico , Valor Preditivo dos Testes , Cuidados Pré-Operatórios , Curva ROC , Reprodutibilidade dos Testes , Estudos Retrospectivos , Sensibilidade e Especificidade , Resultado do Tratamento , Procedimentos Cirúrgicos Vasculares/métodosRESUMO
PURPOSE: The aim of this study was to validate a 64-row multidetector computed tomography (64-MDCT) acquisition protocol with biphasic administration of contrast medium for comprehensive assessment of the coronary and systemic arterial tree in a single examination. MATERIALS AND METHODS: The scanning protocol comprised two acquisitions: an electrocardiograph (ECG)-gated scan at the level of the heart, followed by a total-body, low-dose scan of the systemic arterial circulation. Twenty patients were evaluated using two different strategies for contrast administration. In ten patients, the delay between the two acquisitions was set at 40 s, whereas in the remaining patients, it varied between 45 s and 65 s. For both strategies, the degree of systemic arterial opacification and the attenuation gradient between arterial and venous structures were quantitatively assessed at six extracoronary locations. Two observers evaluated in consensus the presence or absence of atherosclerosis and the degree of stenosis of arterial segments. RESULTS: Three hundred coronary segments were analysed. Arterial-wall changes were depicted in 155 (51%) segments, and in 35 (23%), the degree of stenosis was > 50%. Of the 640 extracoronary arterial segments, 250 (39%) presented atherosclerotic wall alterations, in 50 (20%), the degree of stenosis was > 50% and five were affected by aneurysmal dilatation. The magnitude of arterial opacification values and attenuation gradients between arterial and venous structures were significantly higher in patients scanned with the 40-s fixed-delay strategy. CONCLUSIONS: Whole-body CT angiography with biphasic administration of contrast agent and fixed scan delay has been shown to be a feasible and reproducible technique. Comprehensive data on the global atherosclerotic burden potentially offer important therapeutic options for subclinical, high-risk segments.
Assuntos
Angiografia/métodos , Aterosclerose/diagnóstico por imagem , Angiografia Coronária/métodos , Tomografia Computadorizada por Raios X/métodos , Imagem Corporal Total/métodos , Idoso , Circulação Sanguínea , Índice de Massa Corporal , Protocolos Clínicos , Meios de Contraste , Doença das Coronárias/genética , Interpretação Estatística de Dados , Eletrocardiografia , Estudos de Viabilidade , Feminino , Frequência Cardíaca , Humanos , Masculino , Pessoa de Meia-Idade , Intensificação de Imagem RadiográficaRESUMO
The purpose of this prospective observational study was the evaluation of the usefulness of MPR reconstructions and virtual endoscopy in the study of the esophageal carcinoma. Thirty-nine patients with esophageal cancer proved by means of endoscopy, underwent preoperative TNM staging with dynamic CT of the chest and abdomen with the aid of 3D rendering. Twenty-six patients underwent surgery, and the CT results were compared with histopathologic findings. In staging the T parameter, the CT with 3D reconstructions and virtual endoscopy, showed a sensitivity of 92% and an accuracy of 88%. In staging lymph nodes, the sensitivity in our study was 85%, the specificity 58%, and the accuracy 69%. Our protocol of the study of the esophageal cancer with 3D CT and virtual endoscopy, demonstrated a high concordance with the surgical and pathologic findings. The 3D reconstructed images were very helpful to the surgeons regarding preoperative planning. We performed an observational enquiry, and although this was a small study, it has, however, confirmed that the 3D imaging of the esophagus represents a valuable advantage to conventional imaging. Further studies with a larger number of patients are needed to prove its superiority to traditional CT imaging of the esophagus.
Assuntos
Adenocarcinoma/patologia , Carcinoma de Células Escamosas/patologia , Neoplasias Esofágicas/patologia , Esofagoscopia , Processamento de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Tomografia Computadorizada Espiral/métodos , Interface Usuário-Computador , Adenocarcinoma/cirurgia , Adulto , Idoso , Carcinoma de Células Escamosas/cirurgia , Meios de Contraste/administração & dosagem , Neoplasias Esofágicas/cirurgia , Estenose Esofágica/patologia , Estenose Esofágica/cirurgia , Feminino , Humanos , Iopamidol/análogos & derivados , Metástase Linfática/patologia , Masculino , Pessoa de Meia-Idade , Sensibilidade e EspecificidadeRESUMO
PURPOSE: The aim of this study was to introduce functional magnetic resonance imaging (fMRI) with T1-weighted turbo fast low-angle shot (FLASH) sequences in the evaluation of oesophageal motility and morphology, to formulate MRI patterns of normality in healthy subjects and to demonstrate the feasibility of the method by obtaining a preliminary experience in the study of subjects affected by oesophageal motility disorders. MATERIALS AND METHODS: Thirty healthy volunteers and seven patients with radiological and manometric diagnoses of oesophageal motility disorders underwent fMRI with dynamic T1- weighted turbo-FLASH (TFL) sequences during the administration of oral contrast material. RESULTS: Evaluation of oesophageal function and morphology proved possible in all subjects, as well as the formulation of normality patterns. In patients with motility disorders, fMRI correctly visualised the typical alterations in agreement with radiological and manometric findings. CONCLUSIONS: Functional MRI sequences acquired during the administration of oral contrast material can evaluate oesophageal transit, providing information on motility and morphology; furthermore, this modality can properly visualise the typical functional and morphological alterations of motility disorders.
Assuntos
Transtornos da Motilidade Esofágica/patologia , Esôfago/patologia , Motilidade Gastrointestinal/fisiologia , Imageamento por Ressonância Magnética , Adulto , Esôfago/anatomia & histologia , Esôfago/fisiologia , Feminino , Fluoroscopia/métodos , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Pessoa de Meia-IdadeRESUMO
The distribution of chloroplast DNA (cpDNA) variation in Italian beech ( Fagus sylvatica L.) populations was studied using PCR-RFLP and microsatellite markers. In total, 67 populations were analysed, and 14 haplotypes were identified by combining the two marker types. A remarkable subdivision of cpDNA diversity in Italian beech was found, as indicated by a high level of genetic differentiation ( G(st)=0.855). The highest level of total haplotype diversity ( h(t)=0.822) was estimated for southern Italian populations. The highest number of haplotypes was found in the central-southern region of the peninsula. The nested clade analysis provided evidence for past fragmentation events that may have been occurred during the Quaternary glaciations and had a major role in defining the genetic structure of the central-southern Italian beech populations. Only one haplotype apparently spread towards the north of Italy along the Apennine chain and reached the Italian slope of the western part of the Alps (Maritime Alps, Liguria). All haplotypes found along the Apennines remained trapped in the Italian peninsula. Southern and central Italy represent hotspots of haplotype diversity for Italian beech.
Assuntos
DNA de Cloroplastos/genética , Fagus/genética , Variação Genética , Filogenia , Análise de Variância , Sequência de Bases , Primers do DNA , Demografia , Geografia , Haplótipos/genética , Itália , Repetições de Microssatélites/genética , Dados de Sequência Molecular , Polimorfismo de Fragmento de Restrição , Dinâmica Populacional , Análise de Sequência de DNARESUMO
Three chloroplast microsatellites (cpSSRs), previously sequence characterized and for which paternal inheritance was tested and confirmed, were used to assess their usefulness as informative markers for phylogeographic studies in Norway spruce (Picea abies K.) and to detect spatial genetic differentiation related to the possible recolonization processes in the postglacial period. Ninety-seven populations were included in the survey. Some 8, 7, and 6 different size variants for the three cpSSRs, respectively, were scored by analysing 1105 individuals. The above 21 variants combined into 41 different haplotypes. The distribution of some haplotypes showed a clear geographic structure and seems to be related to the existence of different refugia during the last glacial period. The analysis of chloroplast SSR variation detected the presence of two main gene pools (Sarmathic-Baltic and Alpine--Centre European) and a relatively low degree of differentiation (RST of about 10%), characteristic of tree species with large distribution and probably influenced by an intensive human impact on this species. Based on our data, we were not able to detect any evidence concerning the existence of additional gene pools (e.g., from Balkan and Carpathian glacial refugia), though we cannot exclude the existence of genetic discontinuity within the species' European range. A large proportion of population-specific haplotypes were scored in this species, thus indicating a possible usefulness of these markers for the identification of provenances, seed-lots, and autochthonous stands.
Assuntos
DNA de Cloroplastos/genética , DNA de Plantas/genética , Árvores/genética , Europa (Continente) , Variação Genética , Genética Populacional , Haplótipos/genética , Repetições de Microssatélites , Reação em Cadeia da PolimeraseRESUMO
We studied the phylogenetic relationships among the three stone pine species, Pinus cembra, P. sibirica, and P. pumila, using chloroplast microsatellites and mitochondrial nad1 intron 2 sequences. The three chloroplast microsatellite loci combined into a total of 18 haplotypes. Fourteen haplotypes were detected in 15 populations of P. cembra and one population of P. sibirica, five of which were shared between the two species, and the two populations of P. pumila comprised four species-specific haplotypes. Mitochondrial intron sequences confirmed this grouping of species. Sequences of P. cembra and P. sibirica were identical, but P. pumila differed by several nucleotide substitutions and insertions/deletions. A repeat region found in the former two species showed no intraspecific variation. These results indicate a relatively recent evolutionary separation of P. cembra and P. sibirica, despite their currently disjunct distributions. The species-specific chloroplast and mitochondrial markers of P. sibirica and P. pumila should help to trace the hybridization in their overlapping distribution area and to identify fossil remains with respect to the still unresolved postglacial re-colonization history of these two species.