RESUMO
PURPOSE: To investigate subfoveal choroidal thickness and subanalyze Haller and Sattler layers in eyes with central serous chorioretinopathy (CSC), uninvolved fellow eyes, and eyes of healthy controls using enhanced depth imaging optical coherence tomography. METHODS: Ocular findings and clinical features of 31 eyes with CSC, 24 fellow eyes and eyes of 30 healthy controls were analyzed retrospectively from October, 2014 to March, 2015. Subfoveal choroidal thickness was measured using enhanced depth imaging optical coherence tomography, and the thicknesses of Haller and Sattler layers were analyzed. RESULTS: Mean subfoveal choroidal thickness and mean thickness of Haller layer were significantly greater in CSC than in fellow eyes (P = 0.043 and P = 0.036, respectively) and in normal control eyes (P < 0.001 each), and those of fellow eyes in CSC patients were significantly thicker than those in normal control eyes (P = 0.018 and P = 0.017, respectively). The thickness of Sattler layer did not differ significantly among these groups (P = 0.519). CONCLUSION: Subfoveal choroidal thickness and the thickness of Haller layer were increased not only in affected but also in uninvolved fellow eyes of CSC patients. Nonvascular smooth muscle cells of the choroid may play a role in the pathophysiology of CSC, in response to increased sympathetic tone.
Assuntos
Coriorretinopatia Serosa Central/fisiopatologia , Corioide/irrigação sanguínea , Músculo Liso Vascular/patologia , Idoso , Capilares/diagnóstico por imagem , Capilares/patologia , Coriorretinopatia Serosa Central/diagnóstico por imagem , Corioide/diagnóstico por imagem , Corioide/patologia , Corantes/administração & dosagem , Feminino , Angiofluoresceinografia , Humanos , Verde de Indocianina/administração & dosagem , Masculino , Pessoa de Meia-Idade , Músculo Liso Vascular/diagnóstico por imagem , Variações Dependentes do Observador , Estudos Retrospectivos , Tomografia de Coerência Óptica , Acuidade Visual/fisiologiaRESUMO
BACKGROUND: Positron emission tomography (PET) during the cold pressor test (CPT) has been used to assess endothelium-dependent coronary vasoreactivity, a surrogate marker of cardiovascular events. However, its use remains limited by cardiac PET availability. As multidetector computed tomography (MDCT) is more widely available, we aimed to develop a measurement of endothelium-dependent coronary vasoreactivity with MDCT and similar radiation burden as with PET. METHODS AND RESULTS: A study group of 18 participants without known cardiovascular risk factor (9F/9M; age 60±6 years) underwent cardiac PET with (82)Rb and unenhanced ECG-gated MDCT within 4h, each time at rest and during CPT. The relation between absolute myocardial blood flow (MBF) response to CPT by PET (ml·min(-1)·g(1)) and relative changes in MDCT-measured coronary artery surface were assessed using linear regression analysis and Spearman's correlation. MDCT and PET/CT were analyzed in all participants. Hemodynamic conditions during CPT at MDCT and PET were similar (P>0.3). Relative changes in coronary artery surface because of CPT (2.0-21.2%) correlated to changes in MBF (-0.10-0.52ml·min(-1)·g(1)) (ρ=0.68, P=0.02). Effective dose was 1.3±0.2mSv for MDCT and 3.1mSv for PET/CT. CONCLUSIONS: Assessment of endothelium-dependent coronary vasoreactivity using MDCT CPT appears feasible. Because of its wider availability, shorter examination time and similar radiation burden, MDCT could be attractive in clinical research for coronary status assessment.
Assuntos
Vasos Coronários/fisiologia , Tomografia Computadorizada Multidetectores , Tomografia por Emissão de Pósitrons , Radioisótopos de Rubídio , Sistema Vasomotor/fisiologia , Idoso , Vasos Coronários/diagnóstico por imagem , Endotélio Vascular/diagnóstico por imagem , Endotélio Vascular/fisiologia , Estudos de Viabilidade , Feminino , Hemodinâmica/fisiologia , Humanos , Modelos Lineares , Masculino , Pessoa de Meia-Idade , Músculo Liso Vascular/diagnóstico por imagem , Músculo Liso Vascular/fisiologia , Fluxo Sanguíneo Regional/fisiologia , Ultrassonografia , Sistema Vasomotor/diagnóstico por imagemRESUMO
OBJECTIVE: The objective of our study was to investigate the feasibility, image quality, and clinical implications of a combined dual-source CT angiography (CTA) protocol to assess aortic root anatomy and aortoiliac vasculature in patients with severe aortic stenosis evaluated for transcatheter aortic valve implantation. SUBJECTS AND METHODS: Eighty consecutive patients (47 women and 33 men; mean age, 82.3 ± 7.8 [SD] years) with severe aortic stenosis evaluated for transcatheter aortic valve implantation underwent a combined single-dose contrast-enhanced dual-source CTA protocol (body weight < 70 kg, 110 mL of contrast medium; ≥ 70 kg, 130 mL) consisting of ECG-gated dual-source CTA of the chest with integrated cardiac CT and ungated CTA of the abdomen and pelvis. Two independent observers measured the dimensions of the aortic root and the aortoiliac vasculature and rated image quality semiquantitatively. Vessel attenuation was assessed. Amenability to transfemoral access was evaluated on the basis of vessel diameter (> 7 mm), anatomy, and the presence of vascular disease. RESULTS: Image quality of the aortic root was diagnostic in all 80 patients, and image quality of the aortoiliac vasculature was diagnostic in 79 patients. Vascular attenuation was greater than 200 HU at any vessel level. The mean diameter of the aortic annulus was 24.1 ± 2.9 (SD) mm. Inter- and intraobserver correlations for aortic root and aortoiliac measurements were high (r = 0.93-0.99). Aortic root dimensions were suitable for transcatheter aortic valve implantation in 65 patients (81%). Thirty-eight patients (48%) were deemed amenable to instant transfemoral access without another vasculature intervention. CONCLUSION: The dimensions of the aortic root and the aortoiliac vasculature can be assessed with a combined single-dose contrast-enhanced dual-source CTA protocol, thereby allowing determination of patient eligibility for transcatheter aortic valve implantation, prosthesis sizing, and evaluation of the access route in one examination.
Assuntos
Valva Aórtica/anatomia & histologia , Valva Aórtica/diagnóstico por imagem , Implante de Prótese de Valva Cardíaca/métodos , Músculo Liso Vascular/diagnóstico por imagem , Tomografia Computadorizada por Raios X , Idoso de 80 Anos ou mais , Estenose da Valva Aórtica/cirurgia , Aortografia , Cateterismo , Feminino , Humanos , Artéria Ilíaca/diagnóstico por imagem , MasculinoRESUMO
RATIONALE AND OBJECTIVES: To examine the correlation between the echogenicity and the components of atherosclerotic plaques in rabbit. METHODS: The atherosclerotic plaque formation in the abdominal aortas of hyperlipidemic or normolipidemic rabbits was stimulated by inserting polyethylene tubing. Intravascular ultrasound (30-MHz, 4.5 F catheter) investigation was performed at locations in the vessel. The intravascular ultrasound images of the plaques were evaluated and compared with the histologic findings. RESULTS: Ultrasound images delineated areas showing hyperechoic or hypoechoic ultrasound beams in the plaques. Histologic studies revealed that the hyperechoic areas were closely associated with a dense fibrous extracellular matrix, whereas the hypoechoic areas corresponded to lesions showing a marked accumulation of foamy macrophages or proteoglycan-rich loose myxoid extracellular matrix with smooth muscle cell proliferation. CONCLUSION: A good correlation between ultrasound images and histologic features was observed. These results suggest that intravascular ultrasound imaging could provide useful information for assessing the tissue characteristics of atherosclerotic lesions.
Assuntos
Aorta Abdominal/diagnóstico por imagem , Arteriosclerose/diagnóstico por imagem , Animais , Aorta Abdominal/patologia , Arteriosclerose/patologia , Modelos Animais de Doenças , Imuno-Histoquímica , Músculo Liso Vascular/diagnóstico por imagem , Músculo Liso Vascular/patologia , Coelhos , UltrassonografiaRESUMO
This study tested the capability of high-frequency, two-dimensional real-time intravascular ultrasound (IVUS) in the detection of dynamic changes of large vessel diameter in vivo. An IVUS-catheter (4.8 French, 20-MHz mechanical transducer) was inserted via the femoral vein, and advanced to the inferior vena cava of anesthetized rabbits (n = 7). The depth of field of the transducer allowed for visualization of the entire cross-sections of both the inferior vena cava (IVC) and the adjacent aorta. Changes in vessel diameter were induced pharmacologically using norepinephrine (NE) and glyceryltrinitrate (GTN), which were injected intravenously before and after the administration of L-NG-nitro-arginine methyl ester) L-NAME, a specific inhibitor of endothelium-derived relaxing factor (EDRF)-biosynthesis. Vasoconstriction and -dilation could be observed continuously from the two-dimensional real-time recordings of vessel cross-sections. Vessel diameters and cross-sectional areas (CA) were measured from still frames at given time intervals of drug infusion, and blood pressure and heart rate were recorded continuously. Following NE, an increase of aortic and a simultaneous decrease of venous CA were observed, while GTN elicited the opposite responses. Inhibition of EDRF was followed by an augmentation of the vascular responses. It is concluded that IVUS is capable of detecting changes in vascular dimensions in vivo. Thus in large vessels, IVUS may become a method for the direct assessment of vasomotion in vivo.
Assuntos
Músculo Liso Vascular/diagnóstico por imagem , Músculo Liso Vascular/fisiologia , Animais , Aorta/diagnóstico por imagem , Arginina/análogos & derivados , Arginina/farmacologia , Contração Muscular/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , NG-Nitroarginina Metil Éster , Óxido Nítrico/antagonistas & inibidores , Nitroglicerina/farmacologia , Norepinefrina/farmacologia , Coelhos , Ultrassonografia , Vasoconstrição/efeitos dos fármacos , Veia Cava Inferior/diagnóstico por imagemRESUMO
Between January 1986 and January 1991, 175 patients with suspected T3 or T4 bronchogenic carcinoma underwent computed tomographic (CT) examination of the chest before thoracotomy. We considered two groups of patients: group 1 includes 98 patients with a paramediastinal mass on standard chest X-ray; invasion of hilar and mediastinal structures was preoperatively investigated with CT and then assessed at thoracotomy. The sensitivity, specificity and accuracy were 72%, 75% and 73%, respectively; positive and negative predictive values were 71% and 76%. In group 2 77 patients had a peripheral tumor suspected of invading the parietal pleura and the soft tissues of the chest wall (patients with evident rib or vertebral invasion were not included). Sensitivity, specificity and accuracy of CT were 52%, 86% and 71%, respectively; positive and negative predictive values were 74% and 70%. We conclude that CT with injection of contrast material is indispensable when direct lung cancer infiltration must be ruled out; its accuracy is however not sufficient to be relied upon in all patients.