ABSTRACT: The objective of our study was to determine factors associated with enhancement on CT pulmonary angiography and CT venography.
Two hundred forty-two cases (83 men and 159 women; mean age, 63 years; age range, 21-92 years) underwent CT pulmonary angiography using a bolus-tracking technique; 189 cases subsequently underwent CT venography 3 minutes after the start of the contrast injection. Two different amounts of nonionic iodine contrast medium were administered: patients weighing > 50 kg who were undergoing both CT pulmonary angiography and CT venography received 450 mg I (group B), whereas all other patients received 300 mg I (group A). The enhancement of vessels was subjectively estimated using a four-point scale, and attenuation values were measured at predetermined levels. Multiple regression analyses were performed with attenuation as the dependent variable and patient age, sex, and weight; amount of contrast medium; scanning delay; and presence of embolism as the independent variables.
The scanning delay for CT pulmonary angiography ranged from 10 to 31 seconds (mean, 19 seconds; SD, 3.3). Subjective estimates of enhancement quality on CT venography were significantly better for group B than for group A (p < 0.001). Multiple regression analyses revealed that body weight and age were the only significant and consistent independent variables associated with enhancement of the pulmonary arteries. The amount of contrast medium, body weight, and scanning delay were the independent variables that were consistently associated with enhancement of the deep veins.
The bolus-tracking technique showed relatively small variations in the scanning delay time. Patient age, body weight, and the amount of contrast medium were the important factors associated with vessel enhancement in combined CT pulmonary angiography and CT venography.
American Journal of Roentgenology 08/2007; 189(1):156-61. · 2.78 Impact Factor
Pediatrics International 11/2005; 47(5):592-4. · 0.63 Impact Factor
ABSTRACT: We describe the successful prenatal diagnosis of hypochondrogenesis by MRI. Fetal MR findings were the presence of a conspicuous cartilaginous structure in the basioccipital region, ill-defined ossification of the cervical vertebral bodies, hypoplastic thorax, retarded ossification of the pubic bones, and broad, short long bones. In contrast, fetal US revealed only the presence of short long bones. MRI accurately delineated the axial skeleton in this case and is an effective clinical tool for diagnosing skeletal dysplasias in utero.
Pediatric Radiology 06/2002; 32(5):373-5. · 1.67 Impact Factor
ABSTRACT: Background: Pulmonary hypoplasia is a common cause of neonatal death. Despite the recent advances in prenatal diagnosis with US, the
diagnosis of pulmonary hypoplasia is difficult. The recent application of fast MR imaging may provide additional valuable
Objective: To evaluate pulmonary hypoplasia in the fetus with MRI.
Materials and methods: The subjects comprised 23 fetuses (18–40 weeks' gestation), including major anomalies diagnosed on fetal ultrasonography
(n = 20), maternal abnormality (n = 2) and one normal twin. MRI was performed with a 1.5-T magnet and half-Fourier acquisition single-shot turbo spin-echo
(HASTE) sequences. MR images were interpreted by three radiologists with special attention to the intensity of the lungs.
The lung-to-liver intensity ratio was calculated by means of region-of-interest (ROI) analysis. The diagnosis of pulmonary
hypoplasia depended on clinical, surgical and autopsy findings.
Results: All fetuses with normal pulmonary development showed high intensity in the lung except for one fetus at 24 weeks' gestational
age. All fetuses with pulmonary hypoplasia showed lung of low intensity.
Conclusions: Low-intensity fetal lung on MRI imaging indicates pulmonary hypoplasia after 26 weeks' gestation.
Pediatric Radiology 08/2001; 31(9):669-672. · 1.67 Impact Factor