Purpose:
Parasitic involvement of the vitreous is rare. Indirect ophthalmoscopy,ultrasonography, and scanning electron microscopy play rolesin imaging intraocular parasites, but spectral domain opticalcoherence tomography (SD-OCT) has not been utilized. We reportthe first case in which SD-OCT of an intraocular parasite andassociated retinal lesions was performed.
Methods:
A 37-year-old Hispanic man presented with uveitic glaucoma anda curved floater in his left eye for one week. Examination revealedan intravitreal parasite. Color fundus photography and SD-OCTwere performed. The parasite was extracted from the vitreouscavity via 23-gauge pars plana vitrectomy.
Results:
Color photograph of the parasite is demonstrated in Figure 1A.Three-dimensional (3D) reconstruction of the parasite is shownin Figure 1B. SD-OCT B-scan revealed two concentric circlessuspended in the vitreous overlying the nasal retina. The internalcircle was hyper-reflective superiorly (Figure 2A) and iso-reflectiveinferiorly (Figure 2B). Macroscopically, the larva was red-brown,3 mm in length, and partially covered by a cuticle with minutebody spines. Due to artifact, the worm was not intact; however,it is most consistent with a Gnathostoma or Hypoderma species.
Conclusions:
This is the first reported case of SD-OCT imaging of an intravitrealparasite. SD-OCT allows non-invasive, high-resolution visualizationand 3D reconstruction of parasitic anatomy. Future SD-OCT ofthese and other parasites may help establish tomographic criteriafor identification of parasitic species.
Keywords: imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) • imaging/image analysis: clinical • vitreous