A technology of vitreomacular traction treatment by single-port intravitreal injection of bacterial collagenase into the foveolar area

Purpose: to develop a technology for the treatment of vitreomacular traction (VMT) with intravitreal injection of bacterial collagenase so that the dosage corresponds to the instruction for use of the drug. Material and methods. We carried out the modeling of a variety of variants of collagenase delivery to the area where it should act, taking into account the standard average anatomical parameters of the normal eye. We used modern facilities available in present-day ophthalmic surgery appliances. Results. A technology of bacterial collagenase delivery to the foveolar region of the retina was developed which ensured the injection of 1 KE dosage as permitted by the instruction for use. 27G caliber instruments, a cannula with a silicone tip and an OMS-800 microscope (Topcon, Japan), equipped with the OFFISS imaging systems, were used to deliver the drug directly to the VMT area of 35 eyes. Of these, VMT could be eliminated in 26 cases (74.3%), the best corrected visual acuity increased by 0.20 ± 0.21 (from 0.46 ± 0.21 to 0.66 ± 0.26). Conclusion. The developed technology of VMT treatment may be used in clinical practice as it ensures an effective concentration of the bacterial collagenase in the fovea area using the minimum dose recommended by the manufacturer in the instruction for drug use while avoiding retinal traumatization during the procedure.