Objective: The purpose of this study is to investigate the physiological pulmonary perfusion pattern in different respiratory phases by calculating the normalized volume center of perfusion intensity.
Methods: Four nonsmoking volunteers underwent single photon emission computed tomography (SPECT) of maximum inspiration and expiration after the injection of Tc-99m-MAA in each respiratory phase at a week's interval. Quantitative analysis by calculating the normalized volume center of perfusion intensity was performed.
Results: Quantitative measurement of the normalized volume center of perfusion intensity showed that the percentage averages of ventrodorsal (Y) shift in maximum respiration were 16% (left) and 15% (right) in the upper part, 15% (left) and 14% (right) in the middle part, 17% (left) and 18% (right) in the lower part, 18% (left) and 16% (right) in each total lung. These readings indicated that the normalized center of pulmonary perfusion activity at maximum expiration moved in the ventral direction in contrast to that at maximum inspiration. In horizontal (X) and craniocaudal (Z) directions, the shift in the normalized center of pulmonary perfusion activity at maximum expiration indicated no agreement in movement direction.
Conclusion: The normalized center of the pulmonary perfusion activity in maximum expiration moved in the ventral direction compared to that in maximum inspiration. This phenomenon might be caused by the increase in physiological intrathoracic pressure and by a definite reserve of pulmonary perfusion.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1007/BF02988630 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Effects of routine postural repositioning on the distribution of lung ventilation and perfusion in mechanically ventilated patients.
Intensive Crit Care Nurs
January 2025
Department of Intensive Care Medicine, Hospital Universitario de La Princesa, Madrid, Spain; Centro de investigación en red CIBERES de enfermedades respiratorias, Instituto de Salud, Carlos III, Madrid, Spain. Electronic address:
Objectives: To analyse the effects on respiratory function, lung volume and the regional distribution of ventilation and perfusion of routine postural repositioning in mechanically ventilated critically ill patients.
Methods: Prospective descriptive physiological study. We evaluated gas-exchange, lung mechanics, and Electrical Impedance Tomography (EIT) determined end-expiratory lung impedance and regional ventilation and perfusion distribution in five body positions: supine-baseline (S1); first lateralisation at 30° (L1); second supine position (S2), second contralateral lateralisation (L2) and third final supine position (S3).
Comparison of the diagnostic performance of non-contrast MR angiography and planar V/Q scintigraphy for pulmonary embolism: a systematic review and meta-analysis.
Eur Radiol
January 2025
Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Brazil.
Objectives: To conduct a meta-analysis of the diagnostic performance of non-contrast magnetic resonance pulmonary angiography (NC-MRPA) and ventilation-perfusion (V/Q) scintigraphy for the detection of acute pulmonary embolism (PE).
Materials And Methods: Systematic searches of electronic databases were conducted from 2000 to 2024. Primary outcomes were per-patient sensitivity and specificity of NC-MRPA and V/Q scintigraphy.
Detecting asymptomatic cement pulmonary embolisms following vertebral augmentation using dual-energy computed tomography pulmonary angiography.
J Formos Med Assoc
January 2025
Department of Medical Imaging, National Taiwan University Hospital, Taipei, Taiwan; Department of Medical Imaging, National Taiwan University Cancer Center, Taipei, Taiwan.
Background And Purpose: Dual-energy computed tomography (DECT) pulmonary angiography can reliably detect cement pulmonary embolisms (CPEs) and parenchymal perfusion defects. This prospective observational study investigated CPEs in asymptomatic patients using DECT.
Methods: We enrolled 42 patients who underwent vertebroplasty or received cement screws for vertebral augmentation, examining them using spinal computed tomography and DECT pulmonary angiography.
The Role of Imaging in Pulmonary Vascular Disease: The Clinician's Perspective.
Radiol Clin North Am
March 2025
Department of Medicine, UT Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-8558, USA; Department of Pediatrics, UT Southwestern Medical Center, 5323 Harry Hines Boulevard, Dallas, TX 75390-8558, USA. Electronic address:
Pulmonary vascular diseases, particularly when accompanied by pulmonary hypertension, are complex disorders often requiring multimodal imaging for diagnosis and monitoring. Echocardiography is the primary screening tool for pulmonary hypertension, while cardiac MR imaging (CMR) is used for more detailed characterization and risk stratification in right ventricular failure. Chest computed tomography (CT) is used to detect vascular anomalies and parenchymal lung diseases.
View Article and Find Full Text PDFRole of Cardiovascular MR Imaging and MR Angiography in Patients with Pulmonary Vascular Disease.
Radiol Clin North Am
March 2025
Radiology Department, Northwestern University Feinberg School of Medicine, Arkes Pavilion, 676 North St Clair Street, Suite 800, Chicago, IL 60611, USA. Electronic address:
Cardiac MR imaging and pulmonary MR angiography (MRA) are important clinical tools for the assessment of pulmonary vascular diseases. There are evolving noncontrast and contrast-enhanced techniques to evaluate pulmonary vasculature. Pulmonary MRA is a feasible imaging alternative to CTA in pulmonary embolism detection.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!