Journal article
CT-measured regional specific volume change reflects regional ventilation in supine sheep
Journal of applied physiology (1985), Vol.104(4), pp.1177-1184
04/2008
DOI: 10.1152/japplphysiol.00212.2007
PMID: 18258804
Abstract
Computer tomography (CT) imaging techniques permit the noninvasive measurement of regional lung function. Regional specific volume change (sVol), determined from the change in lung density over a tidal breath, should correlate with regional ventilation and regional lung expansion measured with other techniques. sVol was validated against xenon (Xe)-CT-specific ventilation (sV) in four anesthetized, intubated, mechanically ventilated sheep. Xe-CT used expiratory gated axial scanning during the washin and washout of 55% Xe. sVol was measured from the tidal changes in tissue density (H, houndsfield units) of lung regions using the relationship sVol = [1,000(Hi - He)]/[He(1,000 + Hi)], where He and Hi are expiratory and inspiratory regional density. Distinct anatomical markings were used to define corresponding lung regions of interest between inspiratory, expiratory, and Xe-CT images, with an average region of interest size of 1.6 +/- 0.7 ml. In addition, sVol was compared with regional volume changes measured directly from the positions of implanted metal markers in an additional animal. A linear relationship between sVol and sV was demonstrated over a wide range of regional sV found in the normal supine lung, with an overall correlation coefficient (R(2)) of 0.66. There was a tight correlation (R(2) = 0.97) between marker-measured volume changes and sVol. Regional sVol, which involves significantly reduced exposure to radiation and Xe gas compared with the Xe-CT method, represents a safe and efficient surrogate for measuring regional ventilation in experimental studies and patients.
Details
- Title: Subtitle
- CT-measured regional specific volume change reflects regional ventilation in supine sheep
- Creators
- Matthew K Fuld - Johns Hopkins UniversityR Blaine EasleyOsama I SabaDeokiee ChonJoseph M ReinhardtEric A HoffmanBrett A Simon
- Resource Type
- Journal article
- Publication Details
- Journal of applied physiology (1985), Vol.104(4), pp.1177-1184
- DOI
- 10.1152/japplphysiol.00212.2007
- PMID
- 18258804
- ISSN
- 8750-7587
- eISSN
- 1522-1601
- Grant note
- HL-64368 / NHLBI NIH HHS
- Language
- English
- Date published
- 04/2008
- Academic Unit
- Roy J. Carver Department of Biomedical Engineering; Radiology; Internal Medicine
- Record Identifier
- 9984197152002771
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