Abstract
Purpose :
To define parameters of success for reflux-free subretinal injection using an assistive robotic system versus manual surgery.
Methods :
Ten freshly harvested porcine eyes underwent a standard pars plana vitrectomy with IOP control under microscopic visualization through a Rescan 700 Zeiss device; followed by subretinal injection using a 41G Teflon needle, with or without the Preceyes Surgical System (PSS). The following parameters were recorded: absence of a Bruch's membrane breach, initiation success and duration to subretinal bleb creation. Surgical iOCT and microscopic recording where analyzed and categorized after completion of the surgery. Surgical success was defined as a creation of a subretinal bleb confirmed by intraoperative oct, while avoiding reflux.
Results :
No breach of Bruch's membrane was observed using either manual or robotic assistance. While static positioning was possible manually in the subretinal space, repeated contact with Bruch's was observed due to physiologic hand tremor. There was no motion while using the PSS. Surgical success was achieved in 80% of PSS assisted surgeries (blebs creation in 100%, with leakage in 20% at the time of retraction). With manual surgery, leakage was observed in all cases, in only 40% of cases could a bleb be successfully created. Leakage was observed at all stages of bleb initiation, injection and retraction of the needle. Time involved in bleb generation was longer while using the PSS which may have bearing on the success.
Conclusions :
Subretinal injection using an assistive robotic system reduces the incidence of reflux and increases the rate of successful bleb formation in this porcine model. The model appears appropriate to study parameters involved in bleb formation and dynamics such as pump flow, duration of injection, and needle design.
This is a 2020 ARVO Annual Meeting abstract.