[A software tool for analysis and quantification of regional pulmonary ventilation using dynamic hyperpolarised-(3)He-MRI].
OBJECTIVE
(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.


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, (3)He amount and (3)He peak flow) were calculated. Due to normalization of signal intensities, these parameters are presented in absolute physical units. The data sets were analyzed on a ROI basis as well as on a pixel-by-pixel basis.


RESULTS
Using the developed software, the measurements were analyzed in 6 lung-healthy volunteers, in one patient after lung transplantation, and in one patient with lung emphysema. The volunteers' parameter maps of the pixel-based analysis showed an almost homogeneous distribution of the ventilation parameters within the lung. In the parameter maps of both patients, regions with poor ventilation were observed.


CONCLUSIONS
The developed software permits an objective and quantitative analysis of regional lung ventilation in absolute physical units. The clinical significance of the parameters, however, has to be determined in larger clinical studies. The software may become valuable in grading and following pulmonary function as well as in monitoring any therapy.
Lehmann
F
F
Klinik und Poliklinik für Radiologie, Johannes Gutenberg-Universität, Mainz.
Knitz
F
F
Weiler
N
N
Gast
K K
KK
Ley
S
S
Schmiedeskamp
J
J
Heussel
C P
CP
Bellemann
M E
ME
Kauczor
H-U
HU
Schreiber
W G
WG
D000368:Aged; D005260:Female; D006371:Helium; D006801:Humans; D007554:Isotopes; D008168:Lung / Q000502:physiology*; D016040:Lung Transplantation / Q000502:physiology*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D008962:Models, Theoretical; D010865:Pilot Projects; D011656:Pulmonary Emphysema / Q000175:diagnosis / Q000503:physiopathology*; D012123:Pulmonary Ventilation; D012984:Software
D007554:Isotopes; D006371:Helium
Ein Auswerteprogramm zur quantitativen Untersuchung der Lungenventilation mittels dynamischer MRT von hochpolarisiertem.