The impact of clostridial collagenase on epiretinal structures of the human retina. Experimental studies

Purpose: to assess the functional results of surgical treatment of macular holes (MH) using the authors’ developed technology preserving the internal limiting membrane (ILM) and compare them with the results of traditional surgery technology involving ILM peeling.Material and methods: 150 MH patients aged 50 to 82 were divided into 2 groups: the main group who underwent surgical MH treatment with ILM preservation and the control group, whose traditional surgical treatment involved ILM peeling. After vitrectomy, the main group patients’ macular areas were treated with a bacterial collagenase solution (1 kU) for three minutes, whereupon it was washed out, the vitreal cavity was dried and treated with platelet-rich plasma. In the control group, ILM was stained and removed, whereupon platelet-rich plasma was applied in the air medium. The anatomical result was assessed by optical coherence tomography data. To assess the functional results, the patients were tested for the best corrected visual acuity (BCVA) and subjected to microperimetry. The observation period was 24 months.Results: in all cases, a significant increase in BCVA was achieved after surgical treatment. After 6 months, the control group showed a tendency to a BCVA decrease, while in the main group BCVA remained stable. In the main group, not a single case showed a decrease in the total retinal photosensitivity below the threshold level of the norm of 24 dB, whilst in the control group, 35 cases (47 %) revealed a retinal sensitivity decrease below 24 dB. The total retinal sensitivity turned out to be significantly lower in the control group as compared to the main group over the entire observation period (p < 0.05). Postoperative scotomas were significantly more frequent after ILM peeling. Absolute scotomas were detected in 7 control group cases, whilst in the main group they were not noted in any case.Conclusion. The developed technology makes it possible to practically eliminate the formation of absolute scotomas and to significantly reduce the formation of relative scotomas in the postoperative period, as well as improve functional results against the traditional method of surgical treatment of MH with ILM peeling.

Section: Discussionunclassified

Functional results of surgical treatment of macular holes fully preserving the internal limiting membrane as compared with the traditional method

Lyskin,

Volodin,

Makarenko

2023

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

Lyskin

Makarenko

2022

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.

Internal limiting membrane peeling in vitreoretinal surgery for rhegmatogenous retinal detachment: clinical results, surgical options, and future prospects

Fayzrakhmanov,

Shishkin,

Klev

et al. 2024

Rhegmatogenous retinal detachment (RRD) is one of the leading causes of primary vision disability, while the majority of RRD patients with RRD are people of active working age. Over the past 50 years, retinal detachment surgery has been progressing rapidly, the rate of success increasing up to 90% or higher. However, the reduction of reoperation risks of reoperations, improvement of functional outcomes and increase of postoperative visual acuity remain topical issues. The main reason for repeated surgical interventions is the proliferative vitreoretinopathy progression, which can lead to epiretinal fibrosis, macular oedema, or retinal detachment recurrence. The review is focused on current literature studies that report the results of internal limiting membrane peeling in cases of RRD surgeries and other optional techniques aimed at reducing the risk of the above mentioned postoperative complications.