To the Editor.
—We observed an interesting and unexpected ultrasonographic phenomenon in a patient whose silicone oil had been removed after successful vitreous surgery for proliferative vitreoretinopathy. During a routine postoperative slit-lamp examination, a few silicone oil droplets were observed circulating in the vitreous cavity. The retina was attached ophthalmoscopically. To document the retinal reattachment, we performed a combined A- and B-scan ultrasonographic examination. To our surprise, a highly reflective image appeared that resembled a shallow or localized retinal detachment (Fig 1). A moment later, the detachment disappeared and we observed highly reflectile short linear images within the vitreous cavity (Fig 2). The images were found to be circulating in a counterclockwise direction.Our explanation of this interesting phenomenon is as follows: the linear reflections were caused by silicone oil droplets. These reflections temporarily consolidated adjacent to the retinal surface and resembled a shallow retinal detachment. This phenomenon is caused
Henneken A, Machemer R. Ultrasonographic 'Oil Droplet Phenomenon'. Arch Ophthalmol. 1991;109(3):320. doi:10.1001/archopht.1991.01080030022015