Though cataract surgery requires millimeter precision, it is still very much a manual procedure requiring steady hands on the part of the surgeon. A new system, developed at Stanford and being commercialized by OpticaMedica Corp. of Santa Clara, CA, uses a combination of a femto-second laser and integrated optical coherence tomography to precisely perform lens capsule extraction. Though current methodology is already relatively safe, the new system may lead to effectively error-free procedures and higher pupil alignment precision required for multifocal and accommodating lenses.
With the new system, a laser can pass through the outer tissue — without the eye being opened — to cut the hole in the capsule and to slice up the cataract and lens, all of which occurs just before the patient enters the operating suite. The laser also creates a multi-planar incision through the cornea that stops just below the outermost surface, which means that the surgeon needs to cut less once the operation begins, as well as decreasing the risk of infection. Because of the laser work, once the operation is under way, the removal of the cut section of the capsule and the sliced-up lens can be done relatively easily, with much less need for the ultrasound energy.
A clinical trial in 50 patients revealed no significant adverse events, supporting the study’s goal of showing that the procedure is safe. What’s more, the laser-based system came much closer to adhering to the intended size of the capsular disc (typically coming within 25 micrometers with the laser vs. 305 micrometers in the manual procedure). And using a measurement that ranks a perfect circle as a 1.0, the researchers found that the laser-based technique scored about .95 as compared with about .77 for the manual approach to cutting the disc from the capsule.
The laser-assisted surgery offered other benefits aside from the capsulotomy. The paper notes that because the laser has already spliced the lens, there’s less need to use the ultrasound probe. Its excessive use in hard cataracts can sometimes create too much heat and damage the corneal endothelium and other surrounding tissue. The laser also can create a multi-planar zigzag pattern for the incision in the cornea, allowing the incision to self-seal and decreasing the likelihood of infection and other complications.
Image: Representative examples of lens capsule extraction by manual capsulorhexis (Row A) are not as close to being perfect circles and less uniform than those from laser capsulotomy (Row B).
Videos of OptiMedica procedure and the followup cataract treatment…
Stanford statement: Laser system developed at Stanford shows promise for cataract surgery …
OpticaMedica press release: OPTIMEDICA’S CATALYS™ PRECISION LASER SYSTEM STUDY PUBLISHED IN SCIENCE TRANSLATIONAL MEDICINE SHOWS MARKED ADVANCEMENT IN CATARACT SURGERY …
Abstract in Science Translational Medicine: Femtosecond Laser–Assisted Cataract Surgery with Integrated Optical Coherence Tomography
