New minimally-invasive shunt
Device made from SIBS which conforms to the curvature of the eye
Dermot McGrath
Published: Tuesday, November 1, 2016
InnFocus MicroShunt two years post-op[/caption]
A new minimally-invasive shunt has demonstrated significant reduction in both intraocular pressure (IOP) and use of glaucoma medication in a long-term study, according
to Isabelle Riss MD.
“This procedure is very simple, with immediate and safe pressure reduction. It can be effectively combined with cataract surgery and the postoperative treatment is very similar to cataract surgery,” Dr Riss told delegates at the XXXIV Congress of the ESCRS in Copenhagen, Denmark.
The patients studied had an average preoperative fully medicated IOP of 24.8mmHg (±6.1mmHg). Two years after implantation of the InnFocus MicroShunt™ (InnFocus Inc., Miami, Florida, USA), the average IOP was reduced 47% from baseline to 13.0mmHg (±4.6 mmHg), and over 70% of eyes recorded an IOP equal to or less than 14mmHg. There was a 79% reduction in glaucoma medications to 0.6 medications per patient, and 74% of patients were entirely off glaucoma medications at two years.
Dr Riss’s study included a total of 79 patients at two centres in Bordeaux, France and Santo Domingo, Dominican Republic. Prior to surgery, patients were either phakic (31/79), pseudophakic (30/79), or phakic with combined phacoemulsification and intraocular lens placement (18/79).
BIOCOMPATIBLE MATERIAL
She noted that the InnFocus MicroShunt is made from SIBS, a highly biocompatible thermoplastic material, which conforms to the curvature of the eye and demonstrates clinically insignificant inflammation and tissue encapsulation. The device is placed in the anterior chamber through an ab externo fornix-based scleral needle track which is created posteriorly to the limbus.
“The lumen of the device at 70 microns is sufficiently large to pass sloughed endothelial cells yet small and long enough to prevent hypotony. Planar fins on the shunt prevent the device from migrating into the anterior chamber and also serve to minimise aqueous humour leakage around the tube,” she said.
Putting the results in context, Dr Riss stated that there were no significant differences in IOP and medication use in patients at one and two years in eyes that were phakic, pseudophakic and combined with cataract surgery at the time of implant.
“The overall reduction in IOP at one and two years was 47% and 48%, and the overall reduction in medication use was 81% and 74%, respectively,” she said.
The safety profile of the device was also excellent, she said, with no long-term sight-threatening adverse events. Transient hypotony of less than 5mmHg after day one was present in 6.3% of patients, all of which resolved spontaneously. There were no long-term sight-threatening adverse events such as endophthalmitis, chronic hypotony, or choroidal haemorrhage, she said.
“The InnFocus MicroShunt is safe, effective and practical in eyes that are phakic, pseudophakic and require concomitant cataract surgery,” she concluded.
Isabelle Riss: isabelleriss@orange.fr