The Development of Suspended Scattering Particles in Motion in a Patient with Exudative Reticular Pseudodrusen

The development and characteristics of suspended scattering particles in motion (SSPiMs) in a patient with exudative reticular pseudodrusen (ERPD) are reported using multimodal imaging modalities. An 82-year-old woman was referred because of persistent macular edema during intravitreal injections of bevacizumab. ERPD associated with types I and II (mixed type) macular neovascularization in both eyes was diagnosed. Bilateral flat irregular pigment epithelial detachments were associated with macular neovascularization in both eyes by optical coherence tomography. An intense oval hypersignal was found at umbo in her right eye, as detected by en face optical coherence tomography angiography. This avascular hypersignal at umbo was SSPiM. No change was noticed in the appearance of SSPiM after intravitreal injection of aflibercept. However, intraretinal hemorrhage developed in Henle's fiber layer a month after the second intravitreal injection of aflibercept. Then, several SSPiMs were unveiled in a perifoveal location a month after uncomplicated cataract surgery. The SSPiMs that developed after cataract surgery were connected to the capillaries in the deep retinal vascular plexus. Temporary SSPiMs could be seen during injections of anti-vascular endothelial growth factor and after cataract surgery in the same eye of a patient with ERPD. SSPiMs detected by optical coherence tomography angiography were neither artifacts nor hypersignals due to neovascularized vessels. SSPiMs were considered to be a unique phase colloidal phenomenon generating pseudoflow in exudative macular disorders.