Analysis of decrease in lung perfusion blood volume with occlusive and non-occlusive pulmonary embolisms.

Area of Science:

• Radiology
• Cardiovascular Imaging
• Pulmonary Medicine

Background:

• Pulmonary embolism (PE) is a significant cause of morbidity and mortality.
• Accurate assessment of lung perfusion is vital for diagnosing and managing PE.
• Dual-energy computed tomography angiography (DECTA) is a key imaging modality for evaluating PE.

Purpose of the Study:

• To quantitatively and visually compare lung perfusion blood volume (PBV) in non-occlusive PE versus occlusive PE.
• To determine if lung PBV in non-occlusive PE differs from that in lungs without PE.

Main Methods:

• 108 patients with suspected acute PE underwent pulmonary DECTA.
• Radiologists evaluated PE nature (occlusive vs. non-occlusive) and perfusion visually.
• Lung PBV was quantified using iodine maps and Hounsfield unit (HU) measurements in lesions and normal lung areas.

Main Results:

• A significant difference in lesion proportion was observed between occlusive (73.0% decreased perfusion) and non-occlusive (76.7% preserved perfusion) PE groups (P<0.001).
• Iodine map HU values were significantly higher in the non-occlusive group (33.8 ± 8.2 HU) compared to the occlusive group (11.9 ± 6.1 HU) (P<0.001).
• No significant difference in HU was found between non-occlusive PE lesions and normal lung areas (33.8 ± 8.2 HU vs. 34.5 ± 6.8 HU; P=0.294).

Conclusions:

• Lung PBV is visually and quantitatively preserved in non-occlusive PE.
• Accurate evaluation of pulmonary blood flow requires lung PBV assessment.
• DECTA provides valuable quantitative data for differentiating PE types and assessing perfusion deficits.