Comparison of the efficacy of robotic-assisted subretinal injection and manual injection in rabbit eyes

Objective  To compare the outcomes of robotic-assisted subretinal injection and manual injection in rabbit eyes.

Methods  Five conventional-grade 3-4-month-old New Zealand white rabbits were used as the animal model. The left and right eyes of each rabbit were assigned to the manual injection group and the robot-assisted injection group for subretinal injection surgery. The injection success rate, needle adjustment times, the tremor amplitude of needle tip, puncture hole diameter, complication rate, and surgical time were compared between the two groups. This study complied with the Regulations on the Management of Laboratory Animals, and the study protocol was approved by the Ethics Committee of Medical Services Biotechnology Co., Ltd. (No. MDSW-2024-054A).

Results  The injection success rate was 100% for both groups. The average needle adjustment times were 0(0, 0) in the robot-assisted injection group, which was lower than 0.2(0, 0.5) of the manual injection group, but the difference was not statistically significant ( U=10.000, P=0.317). The average tremor amplitude of needle tip was (5.0±3.6) pixels in the robot-assisted injection group, which was significantly lower than (18.4±6.1) pixels in the manual injection group ( t=6.519, P=0.003). The average puncture hole diameter was (51.7±36.3)μm in the robot-assisted injection group, which was lower than (202.8±136.4)μm of the manual injection group ( t=2.185, P=0.094). The operative time was (8.2±4.0) minutes in the robot-assisted injection group, which was significantly longer than (4.6±1.9) minutes of the manual injection group ( t=-3.674, P=0.021). No complications such as retinal or choroidal damage were observed during the experiment.

Conclusions  The robotic-assisted subretinal injection improve injection stability and accuracy.