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Microincision vitrectomy surgery: experimental visualization and quantification of vitreous contamination
Yumiko Machida1, Hiroyuki Nakashizuka2, Jun Shoji1
1Division of Ophthalmology, Department of Visual Sciences, Nihon University School of Medicine, Nihon University Hospital, 1-6 Kandasurugadai, Chiyoda-ku, Tokyo, 101-8309, Japan.
Background:
To visualize and quantify vitreous contamination following microincision vitrectomy surgery (MIVS) using an experimental vitreous contamination model (EVCM).
Methods:
Enucleated porcine eyes with fluoresbrite carboxylate microspheres applied to the conjunctival surface were used as a type 1 EVCM. Twenty-five- or 27-gauge (G) trocar cannulas were inserted through the conjunctiva and sclera, followed by the placing and opening of an infusion cannula. These procedures were monitored by an intraocular fiber catheter. Secondly, condensed microspheres were applied to an excised sheet of porcine sclera to serve as type 2 EVCM. Twenty-five- or 27-G trocar cannulas were inserted perpendicularly through the top of the sclera where the condensed microspheres were applied, an infusion cannula was inserted, 0.1 mL of saline solution injected through the infusion cannula, and samples collected. The fluorescence strength of samples was then measured using fluorophotometry.
Results:
We visually detected fluorescent microspheres in 10/10 eyes with 25-G and 10/10 with 27-G MIVS. In the experimental quantification study, each MIVS gauge value was significantly higher than the control (P < 0.01). However, there was no significant difference between 25-G and 27-G MIVS.
Conclusions:
MIVS carries the risk of introducing contamination directly into the eyes when the trocar cannula is inserted and infusion cannula is opened, even when a 27-G MIVS is used. Our study has shown it is essential that the surgeon be aware of the possibility of introducing contamination from the conjunctiva at all times during MIVS.
Insights
Microincision vitrectomy surgery (MIVS) can introduce ocular contamination, even with smaller 27-gauge instruments. Surgeons must remain vigilant about potential contamination from the conjunctiva during MIVS procedures.
Area of Science:
- Ophthalmology
- Surgical Innovation
- Ocular Microbiology
Background:
- Microincision vitrectomy surgery (MIVS) is a minimally invasive technique.
- Potential for ocular contamination during MIVS requires investigation.
- An experimental vitreous contamination model (EVCM) was developed.
Purpose of the Study:
- To visualize and quantify vitreous contamination following MIVS.
- To assess contamination risk associated with different MIVS gauge sizes.
- To evaluate the efficacy of an experimental vitreous contamination model.
Main Methods:
- Developed two types of EVCM using porcine eyes and sclera with microspheres.
- Inserted 25-G and 27-G trocar cannulas into the EVCM.
- Quantified contamination using fluorophotometry after saline injection.
Main Results:
- Fluorescent microspheres were detected in all MIVS eyes (10/10 for 25-G and 27-G).
- MIVS procedures showed significantly higher contamination than controls (P < 0.01).
- No significant difference in contamination was observed between 25-G and 27-G MIVS.
Conclusions:
- MIVS, including 27-G, poses a risk of direct ocular contamination.
- Contamination can occur during trocar and infusion cannula insertion/opening.
- Surgeons must maintain awareness of conjunctival contamination risks during MIVS.
