Optimization of pulmonary blood flow analysis method using dynamic chest radiography.

Area of Science:

• Medical Imaging
• Cardiovascular Imaging
• Pulmonary Hypertension Research

Background:

• Dynamic chest radiography (DCR) is used for pulmonary blood flow analysis.
• Pixel values in a left ventricle region of interest (ROI) serve as reference signals.
• The impact of ROI placement on analysis accuracy remains unclear.

Purpose of the Study:

• To determine optimal ROI locations for clinically useful DCR images with enhanced signal values.
• To improve the accuracy of pulmonary blood flow analysis using DCR.

Main Methods:

• Analysis of 40 DCR, SPECT, CTA, and angiography datasets from 15 patients with chronic thromboembolic pulmonary hypertension.
• Calculation of the time difference rate of each peak value (PD%) based on reference signals and heart rate phase.
• Categorization and statistical comparison of PD% values for high- and low-signal ROIs, with visual inspection using CTA.

Main Results:

• Significant differences in PD% were observed when ROIs were placed in upper and inside heart regions on DCR (p < 0.05).
• Low-signal ROIs on CTA were typically located centrally, involving the right ventricle and excluding the left ventricular cavity.

Conclusions:

• Identified specific ROIs yielding higher signal values in DCR for pulmonary blood flow analysis.
• Findings are expected to enhance the efficiency and reliability of DCR imaging for diagnosing chronic thromboembolic pulmonary hypertension.