A free-floating vitreous cyst may be overlooked in patients with persistent floaters when symptoms are attributed to vitreous degeneration.

Researchers described a 51-year-old female patient with persistent floaters in her left eye for over 2 decades that recently become more bothersome. Best-corrected visual acuity was 20/60 in the affected eye. Fundus examination and multimodal imaging revealed a mobile, free-floating pigmented cyst within the vitreous cavity. The cyst had a translucent lumen and was not attached to the optic disc or peripheral retina.

The patient had no signs of intraocular inflammation, and serologic testing for parasitic infection was negative. Because her symptoms persisted, she underwent pars plana vitrectomy to remove the cyst. Histopathologic examination showed a cyst wall lined by pigmented cuboidal epithelial cells, which supported an origin from the pigmented epithelium of the iris or ciliary body.

At 2 weeks postsurgery, the patient reported symptom relief, and best-corrected visual acuity improved to 20/25. The researchers noted that vitrectomy may be considered in selected symptomatic cases, particularly when complete removal and histopathologic confirmation are desired.

The report was limited to a single patient, and the postoperative assessment occurred 2 weeks postsurgery. Accordingly, the clinical course and surgical outcome should not be generalized beyond this case.

The findings highlighted the potential for vitreous cysts to remain symptomatic for years and be mistaken for more common causes of floaters. Careful dilated fundus examination, multimodal imaging, and exclusion of inflammatory or parasitic disease may establish the diagnosis.

“A free-floating vitreous cyst should be considered in the differential diagnosis of persistent floaters,” wrote lead study author Ngo Thi Hong Tham, of the Department of Vitreous and Retina at the Vietnam National Eye Hospital, and colleagues.

The study authors reported no conflicts of interest.

Source: JFO Open Ophthalmology