Abstract
Purpose:
To identify the presence of emulsified silicone oil droplets in optic nerve, retina and vitreous with multimodal imaging.
Methods:
This was a retrospective review of 15 eyes of 15 patients (9 males and 6 females), with a mean age of 63 (range from 29-86), who underwent vitrectomy and silicone oil tamponade. After silicone removal surgery, clinical examination, ultrasound and OCT was performed to identify if there were any remaining silicone droplets in vitreous cavity, retina or optic nerve. Adaptive optics was performed in three patients.
Results:
Silicone oil emulsification was confirmed by multimodal imaging in 12 eyes of 12 patients. With color photography, red-free and near inferred image, emulsified silicone oil can be detected if the droplet is big enough. In ultrasound, emulsified silicone oil can be easily detected as obvious highly reflective dots in the vitreous cavity. In OCT, droplets have several manifestations in retina or optic nerve: 1) Clear bubbles with/without hyper-reflective tails; 2) Hyper-reflective dots with/without hyper-reflective tails; 3) Hyper-reflective tails without observable dots or bubbles. Adaptive optics confirmed these oil droplets even they are very tinny in three patients.
Conclusions:
Hyper-reflective tails behind hyper-reflective dots is a peculiar optical effect. We believe that “lensing effect” or “multiple scattering” could be one of the possible explanations for this artifact. Emulsified silicone oil may be imaged in many ocular tissues. Representation varies with techniques. Interpretation of these images is very important for the retinal specialist to fully understand the possible impact of emulsified silicone oil on retina and its function. At present, we believe ultrasound is the best way to demonstrate emulsified silicone oil droplets in vitreous. OCT is useful for detecting them in retina and optic nerve and adaptive optics is an additional and confirming imaging method if available.
Keywords: 764 vitreous substitutes •
552 imaging methods (CT, FA, ICG, MRI, OCT, RTA, SLO, ultrasound) •
688 retina