RESUMEN
BACKGROUND: Myocardial functional recovery after revascularization is considered the "gold standard" for myocardial viability (MV) assessment. However, the patency of the revascularized coronary artery affects myocardial functional recovery in patients subjected to coronary artery bypass grafting (CABG). The influence of graft patency on viability results has not been widely studied. PURPOSE: We evaluated the effect of graft patency on the prediction of MV after CABG by myocardial contrast echocardiography (MCE) and low-dose dobutamine stress echocardiography (LD-DSE). METHODS: Fifty-three subjects with chronic ischemic heart disease scheduled for CABG were divided randomly into groups A (n = 26) and B (n = 27). They underwent MCE and LD-DSE preoperatively. Patients were followed up 12 months after CABG. Group B patients underwent multislice computed tomography angiography to assess CABG patency, and patients with obstructed grafts were excluded. Group A patients were not subjected to multislice CT angiography. The accuracy of MCE and LD-DSE for assessing MV between the two groups was compared. RESULTS: The accuracy and positive predictive values of MCE and LD-DSE for predicting MV were higher in group B than in group A (p < 0.05). CONCLUSIONS: Preoperative LD-DSE and MCE ability to predict MV depends on the patency of CABG.
Asunto(s)
Agonistas de Receptores Adrenérgicos beta 1 , Medios de Contraste , Puente de Arteria Coronaria , Dobutamina , Ecocardiografía de Estrés , Isquemia Miocárdica/cirugía , Fosfolípidos , Hexafluoruro de Azufre , Anciano , Estudios de Seguimiento , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada Multidetector , Isquemia Miocárdica/diagnóstico por imagen , Variaciones Dependientes del Observador , Valor Predictivo de las Pruebas , Cuidados Preoperatorios , Sensibilidad y Especificidad , Resultado del TratamientoRESUMEN
BACKGROUND: Posterior pedicle screw device is widely used in treatment of thoracolumbar burst fractures. As the clinical operation is not based upon quantitative data of adjustments, the results are not optimal. At present, no study has assessed the associations between the device adjustments and the restoration of stiffness. We investigated the biomechanical effects that adjustments of a pedicle screw device had on the burst fracture, and explored an optimal adjustment. METHODS: Burst fractures were produced at L1 vertebra in 24 fresh calf spines (T12-L3). The specimens were divided into four groups at random. Pedicle screw devices were attached to T13 and L2. Four device adjustments, consisting of distraction and extension, were applied. Adjustment 1 was pure 6° extension, adjustment 2 was pure 5 mm distraction, adjustment 3 was 6° extension followed by 5 mm distraction, and adjustment 4 was 5 mm distraction followed by 6° extension. The effect of each adjustment on the stiffness restoration, anatomical reduction, and neural decompression for the burst fractures was analyzed and evaluated. RESULTS: Pure extension (Group 1) produced the closest segment height and the least restoration of the canal to the intact. Pure distraction (Group 2) restored stiffness most, but with only 60% stiffness of the intact value, and lost the segmental angle most to the intact. The combination of extension-distraction (Group 3 and Group 4) produced the maximum reduction of the anatomy and restoration of the canal in the burst fracture, and the least stiffness restoration. The sequence of extension and distraction did not affect stiffness restoration, anatomical reduction, and neural decompression. CONCLUSIONS: The device adjustments affected stiffness restoration, anatomical reduction, and neural decompression. The combined extension-distraction adjustment may be the most suitable considering the anatomical reduction and neural decompression, but the stiffness decreased the most; it should be considered to reconstruct L1 vertebra.
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Fijación Interna de Fracturas/instrumentación , Vértebras Lumbares/lesiones , Fracturas de la Columna Vertebral/cirugía , Vértebras Torácicas/lesiones , Animales , Fenómenos Biomecánicos , Bovinos , Femenino , Vértebras Lumbares/cirugía , Masculino , Fracturas de la Columna Vertebral/fisiopatología , Vértebras Torácicas/cirugíaRESUMEN
OBJECTIVE: To investigate the value of multi-slice computed tomography in diagnosis of different types of coronary atherosclerotic plaques. METHODS: Twenty-eight patients undergoing CT angiography (CTA) with normal coronary arteries were randomly selected to measure the CT values of different sections of the 4 main branches of coronary artery. Twenty-five specimens of human heart from the bodies of the patients who died of non-cardiogenic diseases were scanned by 16-slice CT scanner and 64-slice CT scanner: a mixture of CT contrast media and normal saline was injected into the coronary arteries to achieve in-vivo-like contrast enhancement within the coronary artery lumen to detect atherosclerotic plaques. The CT values of plaques were measured in several regions of interest (ROI) selected in each plaque. The CT images thus obtained were evaluated by 2 experienced radiologists. There are nine specimens with coronary atherosclerotic plaques among them. Then the atherosclerotic lesions in the coronary were made into tissue specimens to undergo pathological examination. RESULTS: 7560 CT values were obtained from the 28 patients. Thirty-eight atherosclerotic plaques were found by CAT in 9 heart specimens and confirmed by pathology. When the CT value of coronary lumen was 370 HU, the predominant lipid-rich plaque showed a mean CT value of 53 +/- 12 HU; the fibrous-rich plaque showed a mean CT value of 106 +/- 17 HU; and the calcified plaque showed a mean CT value of 429 +/- 94 HU measured by 16-slice CT; and the predominant lipid-rich plaque showed a mean CT value of 51 +/- 13 HU; the fibrous-rich plaque showed a mean CT value of 110 +/- 19 HU; and the calcified plaque showed a mean CT value of 435 +/- 87 HU measured by 64-slice CT. The CT value of the fibrous-rich plaque was significantly higher than that of the lipid-rich plaque (P = 0.008), and lower than that of the calcified plaque (P < 0.01). There was no significant difference between the results obtained by the two kinds of CT scanners. CONCLUSION: CTA can non-invasively assess the atherosclerotic plaques.
Asunto(s)
Angiografía Coronaria/métodos , Enfermedad de la Arteria Coronaria/diagnóstico , Tomografía Computarizada Espiral/métodos , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y EspecificidadRESUMEN
BACKGROUND: Triple-phase enhancement of multi-slice computed tomography (MSCT) has markedly improved the diagnostic accuracy of hepatocellular carcinoma (HCC), and MSCT angiography (MSCTA) has been proved useful in detecting vascular anatomy noninvasively. This study aimed to explore the value of MSCTA by triple-phase enhancement in preoperative evaluation of HCC. METHODS: Fifty-six consecutive cases of primary HCC scheduled for resection were studied with MSCTA by triple-phase enhancement. The raw data images were processed on a workstation for multiplanar reconstruction (MPR) and three-dimensional (3D) reconstruction. The findings after processing of the data were compared with those after surgery or intraoperative sonography. RESULTS: The false positive rate of MSCTA by triple-phase enhancement was 10.1% and its false negative rate was 4.3% in detecting HCC. No significant difference was observed in MSCTA and surgery or intraoperative sonography in detecting vascular anatomy anomalies and pathologic variations, whereas significant difference was found in detecting bile duct invasion with MSCT compared to intraoperative sonography. CONCLUSIONS: MSCTA by triple-phase enhancement not only improves the detection of HCC, but also provides valuable preoperative information about hepatic vascular architecture and parenchyma. MSCTA by triple-phase enhancement is worthy of application as a non-invasive method in preoperative evaluation of HCC.