Over the last few years there have been many exciting developments in ophthalmology and, in particularly, anterior segment technologies. Here’s a review of the emerging trends in cataract, refractive, and glaucoma surgery, as well as dry eye.
Cataract Surgery
The hottest topic over the past decade has been femtosecond laser-assisted cataract surgery. However, cost of these laser platforms has been a barrier to entry for many surgeons. As a result, the latest trend appears to be developing more cost-effective methods for creating a precise and reproducible capsulotomy.
Automated capsulotomy devices include the Zepto (Mynosys, a disposable nanopulse device that is inserted through a 2.2 mm incision and cuts a 5.2 mm capsulotomy), ApertureCTC™ (International Biomedical Devices, a retractable ring filament system that fits through a 1.8 mm incision and creates a thermal capsulotomy of various sizes), and CAPSULaser (Excellens, another thermal capsulotomy device that utilizes a microscope mounted laser with trypan blue capsular staining and a handheld contact lens).
The other significant area of focus in cataract surgery is new advanced technology intraocular lens implants (IOLs). A variety of multifocal, accommodating, and extended depth of focus IOLs and various add powers and toric versions of the same are approved in the U.S. The most recent additions to this class of IOLs include the TECNIS Symfony® and Symfony Toric (AMO) and the AcrySof® IQ ReSTOR® multifocal toric (Alcon), which join the previously available ReSTOR multifocal, TECNIS multifocal and toric, and the Crystalens® and Trulign™ (B+L) implants.
U.S. surgeons now have expanded options to offer patients and are now able to choose from a larger selection of technologies to individually tailor the appropriate lens for each patient. The recent approvals are also encouraging because they may signal a trend toward future clearance of other IOL technologies such as trifocal, light adjustable, and accommodating lenses, which we are eagerly awaiting.
Refractive Surgery
The two emerging trends are corneal inlays for the treatment of presbyopia and the small incision lenticule extraction (SMILE) procedure for laser vision correction of myopia.
Corneal inlays are placed in an intrastromal pocket or under a corneal flap in the nondominant eye of presbyopic individuals to improve near vision. The KAMRA™ and Raindrop corneal inlays gained FDA clearance recently. The KAMRA inlay (AcuFocus) is a small aperture optic that increases depth of field via the pinhole effect, while the Raindrop® Near Vision Inlay (ReVision Optics) is a hyperprolate implant that steepens the central cornea to produce a multifocal effect.
A third design, not yet FDA approved, is the Flexivue Microlens™ (Presbia), which is an implant with refractive power that produces low myopia for monovision.
An alternative to LASIK surgery is the new SMILE procedure. This minimally invasive refractive surgery technique uses the VisuMax® Femtosecond Laser (Carl Zeiss Meditec) to cut a central corneal lenticule that is dissected free and extracted through a small superior incision. The resulting corneal flattening corrects myopia between -1.00 to -8.00 diopters.
Glaucoma
Advances in minimally invasive glaucoma surgery (MIGS) continues to be the hottest trend in the subspecialty of glaucoma. Until recently, the only MIGS devices available to U.S. surgeons were the EX-PRESS® minishunt (Alcon), iStent® (Glaukos), Trabectome® (NeoMedics), and Canaloplasty (iScience Interventional).
The newest additions to the MIGS armamentarium are the CyPass® Micro-Stent (Alcon) and the XEN® Glaucoma Treatment System (Allergan). The former is a small stent inserted into the supraciliary space that enhances uveoscleral outflow in patients suffering from primary open angle glaucoma, and the latter is a porcine gelatin tube that produces an alternative pathway for aqueous outflow to the subconjunctival space in patients unresponsive to maximum tolerated topical glaucoma medications or in those with failed prior glaucoma surgery.
Additional devices awaiting FDA clearance are the Hydrus™ Microstent (Ivantis) 8 mm scaffold device that dilates the canal, the iStent inject® (Glaukos) allows easier delivery of 2 devices into the trabecular meshwork from a single preloaded injector, and the iStent Supra® (Glaukos) is a 4 mm straight tube placed in suprachoroidal space.
Dry Eye
The emerging trend of novel dry eye treatments is very exciting. Until recently, patients with dry eye disease had limited treatment options — topical lubricating drops, punctal plugs, and/or Restasis® (Allergan; cyclosporine).
Fortunately, this is changing. Xiidra® (Shire; lifitegrast) a topical integrin antagonist drop that interferes with T-cell mediated inflammation was approved by the FDA last year to treat the signs and symptoms of dry eye. And the Oculeve Intranasal Tear Neurostimulator (Allergan) a handheld electrostimulation device that activates the lacrimal nerve to increase tear production, is pending FDA clearance.
Furthermore, there are a number of drugs currently under investigation for the treatment of dry eye, and another formulation of cyclosporine, Seciera™ (Sun Pharma), should be available soon. Outside the U.S., Diquas® (Santen; diquafosol) is a P2Y2 receptor agonist that increase tear fluid and mucin secretion.