Cataract surgery gets a new type of surgery in the form of DisCoVisc. It is promising to be complication free as compared to existing surgeries. But is it better than Healon Surgery?
The DisCoVisc ophthalmic surgery device can be used as an alternative to the Healonviscoelastic device in cataract surgery, according to a study presented here at the 72nd Annual Meeting and Exhibition of the Canadian Ophthalmological Society (COS).
"We would use DisCoVisc in situations where we want to provide more endothelial protection to the eye," explained Stanley Chan, MD, Department of Ophthalmology, University of Alberta, Edmonton, Albertae
What is Healon Surgery?
Healon, a viscoelastic preparation of Sodium hyaluronate, has been reported effective in posterior segment surgery for dissection of epiretinal membranes, i.e. proliferative diabetic retinopathy and macular pucker. A more viscous substance might be more effective for this kind of surgery.
Therefore, a new Sodium hyaluronate preparation Healon GV with a ten times greater viscosity at rest than Healon, was tested in an open clinical study.
Twenty-four patients of both sexes and not younger than 18 years were enrolled. The follow-up time was three months. The main indications for using Healon GV were: to separate membranes from the retina, to stop bleeding and to reposition a detached retina.
0.2-0.5 ml of Healon GV was injected through a 27 gauge bent cannula and at close of surgery irrigated out of the eye. Postoperatively the patients were monitored concerning intraocular pressure, vitreous clarity, anterior chamber flare and visual acuity. Healon GV was found to make the surgical procedure simpler and safer. No inflammatory reaction and no increase of IOP was observed.
What is DisCoVisc surgery?
DISCOVISC® Ophthalmic viscosurgical device is the first cohesive and dispersive viscoelastic to combine higher viscosity cohesives and lower viscosity dispersives in a single syringe to provide superior retention, space maintenance and visual clarity during all key phases of cataract surgery. Additionally, it is easily removed at the end of surgery.
A total of 33 eyes of 21 patients were randomised to cataract surgery: 19 eyes to the Healon device and 14 to DisCoVisc.
Researchers documented surgical factors such as phacoemulsification time, total case time, subjective surgical performance, and surgical complications.
No significant surgical complications occurred with either surgical device, according to Dr. Chan.
Corneal pachymetry rose the first day after surgery by an average of 33 microns in the DisCoVisc group versus 48 microns in the Healon group.
At day 15, a relative increase in corneal thickness remained among patients who were subjected to the Healon device (18 microns) compared with those subjected to the DisCoVisc (4 microns).
Less loss of endothelial cell density was found in DisCoVisc group at day 15: average loss 294 cells/mm2 (11.5%) with DisCoVisc versus 470 cells/mm2 (17.9%) with the Healon device.
Patients did not make any subjective assessments that indicated a difference between the devices, noted Dr. Chan.
However, surgeons indicated subjectively that using the DisCoVisc device during phacoemulsification was superior to using the Healon device.
"From a surgical standpoint, there was significant improvement in the retention of viscoelastic with DisCoVisc," said Dr. Chan.
On the other hand, the investigators found that the Healon device was easier to remove at the end of surgery.
More study is needed to confirm the positive impact of using the DisCoVisc device on endothelial cell density and corneal thickness, said Dr. Chan.
The above story leads us to a point from where we can only hope for a much comprehensive effort from the researchers in order to make the new technology as effective compared to the existing technologies.