The Value of Spectral CT Imaging Iodine-Based Material Decomposition Images and Iodine Concentration Quantification in Diagnosis of Pulmonary Embolism

  • Xiuzhi Shen
Keywords: Spectral CT Imaging Iodine-Based Material Decomposition Images, Iodine Concentration Quantification, Diagnosis, Pulmonary Embolism

Abstract

To investigate the value of spectral CT imaging iodine-based material decomposition images and iodine
concentration quantification in diagnosis of pulmonary embolism. A total of 90 patients who were highly
suspected of PE and underwent multi row spiral CT pulmonary arteriography (CTPA) in the thoracic surgery
department of our hospital from December 2018 to December 2019 were selected and divided into control group
(non PE patients, n = 48) and observation group (PE patients, n = 42) based on the CTPA image and iodinebased
material decomposition images. The iodine concentration in the interested area of each subject was
analyzed by iodine-based material decomposition images, and the iodine concentration in the lung tissues was
quantitatively analyzed, to evaluate the perfusion of lung tissues. The two lung fields were divided into six parts:
upper lobe, middle lobe and lower lobe. The average iodine concentration of each lobe of patients in the control
group was detected, the position and quantity of abnormal iodine perfusion in the lung of the observation group
were searched and recorded, and their level of iodine concentration was detected. At the same time, the
contralateral normal lung parenchyma of the same layer or the homolateral normal lung parenchyma of the
adjacent layer was measured. The iodine concentration in the low perfusion area of the observation group was
compared with that in the normal lung tissue and the same area of the control group. ROC curve was used to
analyze the value of spectral CT imaging iodine-based material decomposition images and iodine concentration
quantification in the diagnosis of PE. The iodine concentration in the right lung tissue was lower than that in the
contralateral normal lung tissue according to the iodine-based material decomposition images and single energy
mixed images. In the control group, there was no significant difference in the average iodine concentration of
lung tissue at the same position on both sides (P >0.05), and there was no significant difference in the average
iodine concentration of the homolateral upper lobe tissues and lower lobe tissues (P > 0.05). There was
significant difference in the average iodine concentration of homolateral upper lobe tissues and middle lobe
tissues, middle lobe tissues and lower lobe tissues (P < 0.05 or 0.01). The average iodine concentration in the
lung tissue of the observation group was significantly lower than that of the control group (P < 0.01). The AUC
of iodine concentration in PE was 0.928, the best value was 0.87mg/ml, the sensitivity was 93.56%, the
specificity was 91.58%, the negative predictive value was 94.15%, and the positive predictive value was 90.41%.
Spectral CT imaging iodine-based material decomposition images and iodine concentration quantification can
accurately reflect the pulmonary blood perfusion of PE patients, provide qualitative and quantitative analysis for
PE, have certain value in the diagnosis of PE, so it can be widely used in clinical practices.

Published
2020-02-01