- A selective target for CAPSULaser is created when the capsule is stained with CAPSULBlue, a specific formulation of trypan blue.
- A fixation laser, coaxial with the view of the surgeon, allows identification of the visual axis location in patients with translucent cataracts in a manner similar to LASIK. In addition, the capsulotomy position is visualized by a scanned aiming laser.
- The surgeon is in control at all times and the capsulotomy is placed at the determined location.
- Once the surgeon has determined the location for treatment, the focused laser is activated and it describes a circle in about 1 second to create the capsulotomy.
The capsulotomy range can be selected from 4.0 to 5.5 mm in 0.1 mm increments.
- Our surgeon advisors recommend that the pupil be at least 1mm greater than the selected capsulotomy diameter.
- A smaller capsulotomy may be utilized if appropriate but try pharmacological dilation first.
- If a small degree of dilation is required, CAPSULVisc 2% can be used to expand the pupil diameter mechanically.
- If the pupil is constricted the use of an expander is recommended.
Miosis was not observed in any of the clinical studies.
In preclinical studies, where the iris was intentionally targeted to determine the consequences of an inadvertent laser interaction, the following reaction was documented:
- Only superficial discoloration of the iris
- No bleeding
- No cutting or tearing
- No distortion
- No miosis
CAPSULaser will not interact with transparent tissue. The capsule needs to be stained with a dye to provide the selective target which only CAPSULBlue provides.
The CAPSULaser technique requires two simultaneous conditions to create a capsulotomy: first a CAPSULBlue stained capsule, and second, the treatment laser focused on the capsule.
No, it is a continuous-wave laser that is always on during the selective laser capsulotomy treatment. It is not a pulsed laser like the femtosecond laser.
There are many differences between CAPSULaser and FLACS.
- The visual axis can be directly identified in surgery for the majority of patients with CAPSULaser.
- CAPSULVisc is utilized with CAPSULaser providing the additional safety associated with an OVD filled anterior chamber.
- The overall surgery time is less for CAPSULaser.
- The laser energy applied to the eye is substantially less for CAPSULaser.
- CAPSULaser is mounted directly to the existing OR microscope.
- CAPSULaser is optimized for the capsulotomy alone.
The laser wavelength is at the peak spectral absorption for CAPSULBlue. The wavelength is in the orange-red range of the spectrum.
CAPSULBlue is optimized for consistent staining of the anterior capsule and for absorption of the wavelength of CAPSULaser. This leads to consistent capsulotomies. It is the only version of trypan blue that has been formulated for selective laser capsulotomy.
For cataract surgery trypan blue selectively stains the lens capsule and non-living cells. Healthy corneal endothelial cells are not stained in vivo, as the cellular membrane naturally prevents dye absorption from the posterior surface.
Corneal surgical techniques, such as DSEK, are different and the donor tissue can be stained with dye through in vitro application via the anterior surface of the membrane. CAPSULBlue is not currently indicated for use in DSEK surgery.
SEM (scanning electron microscopy) images show that the capsule with a “rolled-over” edge, consequently the two layers of tissue at the rim present a darker blue color. This enhances visualization for the remaining steps of the cataract procedure.
The “rolled-over” characteristic of the edge created by CAPSULaser generates a strong capsulotomy that is resistant to tearing.
- Preclinical studies on human cadaver eyes at SERI (Singapore Eye Research Institute) have demonstrated that the capsulotomy rim strength is at least equivalent to manual and FLACS.
- The mechanism of action of the laser on the capsule enhances its elasticity and preclinical studies have shown that the capsulotomy can be extended from 5 to 12 mm without tearing.
In surgery over 90% of the CAPSULBlue is removed by rinsing unabsorbed dye and extraction of the stained capsular disk during surgery. The remaining trypan blue (CAPSULBlue) washes out of the eye naturally within a few hours following surgery.
On a global basis, trypan blue is used in over 10% of cataract surgeries for complex cataract cases and training. Trypan blue has a great safety profile as reported in the peer-review literature and the FDA MAUDE database.
At 12 months and longer-term follow-up, fibrosis has not been observed.
The high optical quality of CAPSULVisc sodium hyaluronate enhances the performance of CAPSULaser and is proven to deliver consistent outcomes.
- CAPSULVisc protects the endothelium for both the capsulotomy and the phaco procedure.
- CAPSULVisc is available in 2% NaHy which is cohesive, and 3% NaHy which is dispersive.
- CAPSULVisc remains in the anterior chamber during surgery to provide endothelium protection but is easy to remove during I/A.
Yes, during clinical evaluation hyper-mature cataracts were treated whilst avoiding anterior tears. The use of CAPSULVisc balances the pressure in the intumescent capsule and provides a stable anterior chamber for the laser to act.
The Patient Interface lens has two functions in the procedure. First, it allows the surgeon to stabilize the eye and center the capsulotomy on the visual axis. Second, it also defocusses the laser providing additional safety for the retina.
The CAPSULaser technique is a Selective Laser Capsulotomy approach that only causes a local thermal effect in the lens capsule.
- First and foremost, the laser energy is only absorbed by the CAPSULBlue.
- Second, the total energy entering the eye is substantially less than a femtosecond-laser procedure and there are no bubbles produced during the CAPSULaser procedure.
- Finally, pre-clinical studies have directly measured peak temperature at the endothelium, iris, and retina. In all cases, the temperature rise was less than 0.2 °C for less than 0.1 s.
- For a comparison to other technologies utilized in cataract surgery, the temperature increase for phacoemulsification is substantially higher for a much longer period of time.
Yes, it complies with all appropriate laser safety standards: FDA CDRH 21CFR1040; IEC 60825-1; ANSI Z136.1-2014; ISO 15004-2, 2007.
© 2018 EXCEL-LENS, Inc
455 North Canyons Parkway,
Livermore, CA 94551, USA
Search our site:
Not currently FDA cleared or approved