# Quantitative assessment of ophthalmic viscosurgical device retention during phacoemulsification and aspiration: an ex vivo analysis

## TL;DR

This study measures how much of a surgical eye gel stays in the eye during cataract surgery, showing how injection volume affects retention.

## Contribution

The paper introduces a quantitative method to assess residual ophthalmic viscosurgical device (OVD) in ex vivo eyes during phacoemulsification and aspiration.

## Key findings

- Using 0.1 mL of dispersive OVD with the soft shell technique, about 60 μL remained after 2 minutes of PEA.
- Injecting 0.15 mL of dispersive OVD left approximately 60 μL after 5 minutes of PEA.
- Injecting 0.05 mL of dispersive OVD resulted in less than 30 μL remaining after 0.5 minutes, offering insufficient corneal protection.

## Abstract

To quantify the amount of residual ophthalmic viscosurgicaldevice (OVD) during phacoemulsification and aspiration (PEA).

A fluorescein-stained dispersive OVD consisting of 3% hyaluronic acid (HA) and 4% chondroitin sulfate (CS) was injected into porcine eyes in volumes of 0.05, 0.1, and 0.15 mL. Subsequently, a cohesive OVD containing 1% HA was injected, and the soft shell technique (SST) was used. Porcine eyes filled with 0.4 mL of dispersive OVD alone were also evaluated. PEA was performed for 0.5, 1, 2, 3, 4, and 5 min, and the amount of dispersive OVD remaining in the eye at each time point was quantified by measuring sulfate ions contained in the CS molecules.

Using the SST with 0.1 mL of dispersive OVD, the corneal endothelium was covered for up to 2 min of PEA, and approximately 60 μL of dispersive OVD remained. With the SST using 0.15 mL of dispersive OVD, approximately 60 μL of dispersive OVD remained 5 min after PEA, but using0.05 mL, less than 30 μL remained 0.5 min after PEA, indicating insufficient protection of the corneal endothelium. With 0.4 mL of the single agent, 60 μL of dispersive OVD remained in the eye, even after 5 min of PEA.

The relationship between the injectate volume of dispersive OVD and the residual volume in the eye over the PEA time was demonstrated quantitatively. To perform SST properly, it is necessary to consider the amount of the dispersive OVD injected.

The online version contains supplementary material available at 10.1007/s00417-025-07073-4.

In most previous ex vivo studies, the time taken to remove dispersive ophthalmic viscosurgical devices (OVDs) from the eye was assessed qualitatively by visual inspection of fluorescein-stained OVDs.There has been no evaluation to date of the amount of residual OVD remaining in the eye during phacoemulsification and aspiration (PEA), relative to the injection volume of dispersive OVD using the soft shell technique.

In most previous ex vivo studies, the time taken to remove dispersive ophthalmic viscosurgical devices (OVDs) from the eye was assessed qualitatively by visual inspection of fluorescein-stained OVDs.

There has been no evaluation to date of the amount of residual OVD remaining in the eye during phacoemulsification and aspiration (PEA), relative to the injection volume of dispersive OVD using the soft shell technique.

By measuring sulfate ions in the chondroitin sulfate molecules contained in the dispersive OVD, we evaluated the amount of dispersive OVD in the eye during PEA.The relationship between the volume of dispersive OVD injected using the soft shell technique and the remaining volume of dispersive OVD in the eye at each PEA time can provide important information related to cataract surgery.

By measuring sulfate ions in the chondroitin sulfate molecules contained in the dispersive OVD, we evaluated the amount of dispersive OVD in the eye during PEA.

The relationship between the volume of dispersive OVD injected using the soft shell technique and the remaining volume of dispersive OVD in the eye at each PEA time can provide important information related to cataract surgery.

The online version contains supplementary material available at 10.1007/s00417-025-07073-4.