Imaging features of Color Doppler Ultrasound, computed tomography and computed tomography dacryocystography in lacrimal sac space-occupying lesions

Abstract Purpose: Lacrimal sac space-occupying lesions (SOLs) are rare and sometimes life-threatening disorders, often misdiagnosed in clinical practices. This study aimed to observe the imaging features of Color Doppler ultrasound (CDU) and computed tomography (CT) or computed tomography dacryocystography (CT-DCG) in different types of lacrimal sac SOLs. Methods: This retrospective case series study included 21 patients with lacrimal sac SOLs who underwent lacrimal sac surgery between January 2018 and March 2022. The imaging features of CDU and CT or CT-DCG in these patients extracted from the examination cloud system were observed and analyzed. Results: 21 patients with lacrimal sac SOLs completed preoperative CDU and CT or CT-DCG examination. CDU showed abnormal lacrimal sac imaging in all cases of SOLs (21/21, 100%), while CT or CT-DCG showed abnormal imaging in 20 cases (20/21, 95.2%). CDU could detect the blood flow signals in all types of space-occupying lesions except mucocele and mucopeptide concretion. Among them, polyps had characteristic imaging changes on CDU and CT-DCG. The mucoceles and mucopeptide concretions had characteristic imaging changes on CDU, which could provide more information for differential diagnosis. Conclusions: CDU can observe the morphology and internal blood flow signals of lacrimal sac SOLs. CT or CT-DCG has advantages in observing structural damage around the lacrimal sac mass. Therefore, CDU may be used as a routine examination to exclude lacrimal sac SOLs before DCR in the absence of preoperative CT or CT-DCG.