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Related Experiment Video

Updated: Feb 13, 2026

Unilateral Lung Volume Analysis Using Micro-CT for Enhanced Assessment of Pulmonary Fibrosis in Preclinical Models
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Volume/perfusion ratio from lung SPECT/CT.

Wolfgang Michael Schaefer, Daniela Knollmann, Jerome Avondo

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    Summary
    This summary is machine-generated.

    A new volume/perfusion ratio (VPR) parameter combining CT lung volume and SPECT perfusion improves identification of target lobes for lung volume reduction procedures in emphysema patients. VPR shows higher sensitivity than individual measures alone.

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    Area of Science:

    • Pulmonary imaging and intervention
    • Radiology and nuclear medicine
    • Respiratory medicine

    Background:

    • Pulmonary emphysema necessitates lung volume reduction procedures (LVRP) to optimize respiratory function.
    • Current methods using relative lobar volume (relVol) from CT for LVRP target identification overlook lobar perfusion.
    • Integrating lobar volume and perfusion data is crucial for accurate LVRP planning.

    Purpose of the Study:

    • To develop and validate a novel parameter, the volume/perfusion ratio (VPR), for optimizing target lobe identification in pulmonary emphysema.
    • To combine relative lobar volume (relVol) from CT and relative perfusion (relPerf) from SPECT into a single, effective parameter.

    Main Methods:

    • Hybrid V-/P-SPECT/CT scans were performed on 20 severe pulmonary emphysema patients before LVRP.
    • Lobar perfusion (99mTc-MAA) and volume were quantified using "HERMES Hybrid 3D - Lung Lobe Quantification".
    • Normal VPR ranges were established from 12 healthy individuals to classify lobes in patients.

    Main Results:

    • In severe pulmonary emphysema patients, 31 lobes exhibited pathological VPR values.
    • Compared to relVol (7 lobes) and relPerf (14 lobes), VPR identified significantly more pathological lobes.
    • Normal VPR values were established for different lung lobes.

    Conclusions:

    • The volume/perfusion ratio (VPR) derived from lung SPECT/CT provides a unified assessment of lobar volume and perfusion.
    • VPR demonstrates superior sensitivity in identifying potential LVRP target structures in severe pulmonary emphysema compared to relVol or relPerf alone.
    • Further clinical trials are needed to ascertain the specificity and prognostic value of VPR.