Search results for "Lung emphysema"
showing 4 items of 4 documents
Clinical aspects of the apparent diffusion coefficient in 3He MRI: results in healthy volunteers and patients after lung transplantation.
2007
Purpose To measure the apparent diffusion coefficient (ADC) after inhalation of hyperpolarized 3He in healthy volunteers and lung transplant recipients, and demonstrate the gravity dependence of ADC values. Materials and Methods Six healthy volunteers, 10 patients after single-lung transplantation, and six patients after double-lung transplantation were examined at 1.5T during inspiration and expiration. The inhalation of 300 mL of hyperpolarized 3He was performed with a computer-controlled delivery device. A two-dimensional fast low-angle shot (FLASH) sequence measured the 3He diffusive gas movement. From these data the ADC was calculated. Results The mean ADC was 0.143 cm2/second in healt…
Ein Auswerteprogramm zur quantitativen Untersuchung der Lungenventilation mittels dynamischer MRT von hochpolarisiertem 3He
2004
Purpose: 3 He-MRI is able to visualize the regional distribution of lung ventilation with a temporal and spatial resolution so far unmatched by any other technique. The aim of the study was the development of a new software tool for quantification of dynamic ventilation parameters in absolute physical units. Materials and Methods: During continuous breathing, a bolus of hyperpolarized 3 He (300 ml) was applied at inspiration and a series of 168 coronal projection images simultaneously acquired using a 2D FLASH-sequence. Postprocessing software was developed to analyze the 3 He distribution in the lung. After correction for lung motion, several ventilation parameters (rise time, delay time, …
Paired Inspiratory/Expiratory Volumetric Thin-Slice CT Scan for Emphysema Analysis
2005
Purpose: The aim of the study was to use three-dimensional high-resolution CT scan data sets in inspiration and expiration for the quantitative evaluation of emphysema. Using an advanced dedicated semiautomatic analysis tool, the functional inspiratory/expiratory shifts of emphysema volume and clusters were quantified. The pulmonary function test (PFT) served as the clinical “gold standard.” Materials and methods: Thirty-one patients (9 women and 22 men; mean [± SD] age, 60 ± 8 years) who had severe emphysema due to COPD (Global Initiative for Chronic Obstructive Lung Disease [GOLD] class III and IV) were included in the study. All patients underwent paired inspiratory/expiratory multidetec…
Reformatierungen als Lösungsansatz für die Problematik der unterschiedlichen Schichtführung beim Vergleich von3He-MRT und HR-CT der Lunge
2003
Purpose: 3 He-MRI of the lung has been shown to be a sensitive method for functional imaging of the lung. A previous study compared 3 He-MRI (coronal planes) with CT (transverse planes) by looking for ventilation defects and their pathomorphologic correlation. Anatomic structures, such as lobar fissures and hilar vessels, were used for orientation, but the reliable assignment of ventilation defects to lung segments is problematic. The present work compares multiplanar reformations of 3 He-MRI and HR-CT, which were generated from planes determined by the respective method, and investigates their suitability as a solution of this problem. Materials and Methods: A total of 16 data sets taken f…