Periocular thelaziasis presenting as an orbital mass – a case report

ABSTRACT

Thelazia callipaeda is a rare parasitic infestation caused by spiruroid nematode of the genus Thelazia. We report a case of a 74-year-old gentleman who presented with a painless swelling of left lower lid since 15 days. Examination revealed a firm mobile mass along the inferior orbital rim. Magnetic Resonance Imaging showed a well-defined preseptal cystic lesion and Ultrasound screening revealed multiple mobile worms within. Patient underwent cyst excision in toto under local anesthesia. Four long refractile worms were isolated from within the cyst cavity. Species identification confirmed the parasite as Thelazia callipaeda. Periocular thelaziasis usually presents as free floating worms in the conjunctival sac, anterior chamber or vitreous cavity. It is important to be aware of this rare entity which should be considered as a differential diagnosis in endemic areas.

KEYWORDS:

• Human zoonoses
• ocular thelaziasis
• oriental eyeworm

Acknowledgment

The authors would like to thank Dr. Olma Veena Noronha, Consultant Radiologist, VRR Scan Center, Chennai for her expert opinion on the MRI and USG scans.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.