Objectives:

To explore the diagnostic value of iodine maps of computed tomographic pulmonary angiography (CTPA) in acute pulmonary embolism (APE) in preoperative patients with ovarian cancer (OC).

Methods:

The data of OC patients who suspected APE before surgery and underwent CTPA examination on 320-slice CT from January 2018 to June 2022 were analyzed. SURE Subtraction Lung software was used to generate subtraction CTPA iodine map

and the diagnostic efficacy of subtraction CTPA iodine map for APE was evaluated based on clinical and imaging data.

Results:

Among 302 OC patients

21 (6.95%) had APE with 70 emboli of pulmonary arteries

including 10 main pulmonary arteries (14.29%)

17 lobar pulmonary arteries (24.29%)

29 segmental pulmonary arteries (41.43%)

and 14 sub-segmental or lower pulmonary arteries (20.00%). Compared with the standard diagnosis

55 cases were detected by CTPA

15 cases were missed and 50 cases were misdiagnosed

and 65 cases were detected by subtraction CTPA iodine map

5 cases were missed and 22 cases were misdiagnosed. The sensitivity and specificity of CTPA alone in diagnosing APE were 57.14% and 82.56%

respectively. The sensitivity and specificity of subtraction CTPA iodine map in diagnosing APE were 85.71% and 92.53%

respectively. In segmental analysis

58 (82.86%) apes showed corresponding wedge-shaped PD on the iodine maps. Compared with normal lung parenchyma

quantitative perfusion in APE-associated PD was significantly lower (0.0380.030 vs 0.1190.035

P

＜0.001).

Conclusion:

Subtraction CTPA iodine map can improve the detection rate of pulmonary micro-emboli and the accuracy of preoperative imaging diagnosis of APE in ovarian cancer patients. The imaging diagnostic efficiency of subtraction CTPA iodine map is higher than that of conventional CTPA.