RESUMEN
PURPOSES: To determine the diagnostic capabilities of dynamic high-resolution electron-beam (HREB) CT scanning for diagnosing bronchiolitis obliterans syndrome (BOS) in lung transplant recipients. MATERIALS AND METHODS: At the time of follow-up examinations after lung transplantation, 52 patients were examined by dynamic HREB CT scan. Visual signs of small airway disease were assessed and compared with lung function. For numerical analysis, the mean lung attenuation and its SD were determined and compared with the course of lung function tests. RESULTS: On visual analysis, significant parenchymal attenuation inhomogeneities were present in eight of nine patients with manifest BOS, and in two of four patients who developed BOS during follow-up. Thirteen of 20 patients with persistent normal lung function displayed homogeneous lung attenuation. On numerical analysis, mean lung attenuation was significantly lower in patients who developed BOS during follow-up than in patients with persistent normal lung function (both in expiration and inspiration, p < 0.0001). With an optimal threshold, the sensitivity was 100% (4 of 4 patients) and the specificity was 90% (19 of 20 patients). In patients with BOS at the time of the CT scan examination, parenchymal attenuation was less homogeneous than in patients with persistent normal lung function (p < 0.0001). With an optimal threshold, the sensitivity was 78% (7 of 9 patients) and the specificity was 85% (17 of 20 patients). CONCLUSIONS: Dynamic HREB CT of lung transplant recipients correlates well with lung function criteria of BOS at the time of the CT examination and with the subsequent progression to BOS.
Asunto(s)
Bronquiolitis Obliterante/diagnóstico por imagen , Trasplante de Pulmón , Tomografía Computarizada por Rayos X/métodos , Adolescente , Adulto , Anciano , Bronquiolitis Obliterante/etiología , Femenino , Estudios de Seguimiento , Humanos , Pulmón/fisiología , Masculino , Persona de Mediana Edad , Complicaciones Posoperatorias , Sensibilidad y EspecificidadRESUMEN
PURPOSE: To compare the diagnostic power of different software implementations for the quantification of coronary artery calcium. MATERIALS AND METHODS: Electron beam computed tomography was performed in 109 heart transplant recipients at the same time as catheter coronary angiography and intracoronary ultrasound. Electron beam computed tomography images were analyzed by 3 software packages marketed for the quantification of coronary calcifications using the same software settings, and the resultant calcium scores correlated with the invasive reference methods by Bland-Altman plots and analysis of the receiver operating characteristics. RESULTS: Although all scoring systems displayed close correlations upon regression analysis (r2=0.94-0.99), their ability to detect disease as per the invasive reference method varied significantly in some instances. The area under the ROC curve varied between Az=0.78 and 0.85 for the detection of coronary artery stenosis upon coronary angiography (P=0.05-0.13), and between Az=0.75 and 0.83 for the detection of accelerated intimal proliferation (P=0.03-0.18). CONCLUSIONS: Different software implementations for the quantification of coronary artery calcium load may display diagnostically relevant differences in spite of close direct correlation.