New Laser Improving Cataract Surgery
The word cataract is used to describe a natural lens that has turned cloudy. Cataracts are not a disease, but rather a condition affecting the eye. As the natural lens inside the eye becomes cloudy, it does not allow light to pass through it as well as it did when it was transparent. Cataracts usually start as a slight cloudiness that progressively grows more opaque. They are usually white, but may take on color such as yellow or brown. As the cataract becomes more mature (increasingly opaque and dense), the retina receives less and less light. The light that does reach the retina becomes increasingly blurred and distorted. This causes gradual, progressive impairment of vision.
Cataracts are mostly due to aging and, hence, are common in older people. However, diabetes, smoking, excessive alcohol use and excessive exposure to sunlight, all are considered as risk factors for cataract development.
What are the symptoms of a cataract?
- A gradual deterioration in vision over time
- Objects may appear yellow, hazy, blurred or distorted
- Vision in bright light or in the sunshine may be difficult due to glare
- Distortions, ghosted images and halos may appear
What cataract could lead to?
If left untreated, cataracts can cause vision problems, blurriness and, sometimes, even needless blindness.
How is a cataract treated?
While conventional preventive and corrective measures such as new eyeglasses, brighter lighting, anti-glare sunglasses, or magnifying lenses can be used to improve vision in people who have cataract, the only effective “cure” or treatment of cataract is surgery. Cataract surgery is one of the most common operations performed, usually with excellent results. During the procedure, the cloudy lens is removed and replaced with an artificial lens (Intraocular lens / IOL).
Generally, cataracts are removed on an outpatient basis, unless admission to the hospital is medically necessary. Most patients are up and about on the day of surgery.
What happens during the cataract surgery?
Cataract surgery is a pain-free experience because of the advances in anesthesia. Patients are awake during the surgery and are able to resume normal activities shortly afterwards. According to a survey conducted by the American Society of Cataract and Refractive Surgery, more than 98 percent of cataract patients had their vision successfully improved after surgery. Many patients experience vision that is actually better than before they developed cataracts. Once removed, cataracts will not return.
The traditional laser surgery for cataract removal is known as capsulorhexis and involves removal of a disc from the capsule surrounding the eye's lens. However, quite recently, a clinical pilot study done on 50 cataract patients found that precision with the new image-guided laser was 10 times better than that obtained with the current standard technique. The revolutionary study also found out that all patients who got the newer laser surgery, reported better vision overall, compared to patients whose surgeries were performed manually by the standard procedure.
Details of the study
The study was done by the researchers and scientists at Stanford University School of Medicine and was published in Nov. 17 issue of “Science Translational Medicine” journal (Femtosecond Laser-Assisted Cataract Surgery with Integrated Optical Coherence Tomography," Volume 2, Issue 58, November 17, 2010). However, it should be noted that the whole study was based on a specific laser system being produced by OpticaMedica Corp. of Santa Clara, Calif., which also funded the study and is considered one of the leading laser manufacturers.
How the new laser procedure differs from the standard procedure?
This new technology based advanced laser procedure is called as capsulotomy (instead of standard capsulorhexis technique) and offers several advantages over the standard manual laser procedure such as:
Ease of performance: The new cataract laser procedure is relatively simple and easy to perform even for the medical residents and hence is less dependent on surgical skill and also allows for greater consistency.
Technology: The technology to perform the new laser is called a capsulotomy instead of capsulorhexis (the one used with the traditional, standard laser) is considered highly advanced, accurate and sophisticated.
Method and procedure: As opposed to the manually performed traditional cataract surgery (capsulorhexis) which involves the initial incision, the breakup and removal of the clouded lens from the lens capsule, all these steps can now be done with a special laser guided by 3-D imaging (known as Ocular Coherence Tomography or OCT) or 3D image guided laser which is programmed to achieve the precise cut specified by the cataract surgeon. The main purpose of this special 3D imaging system is to help aim the laser.
Precision and strength: According to the study, the new laser procedure cuts circles in lens capsules that are 12 times more precise than those achieved by the traditional method, as well as leaving edges that are twice as strong in the remaining capsule, which serves as a pocket in which the surgeon places the plastic replacement lens.
Safety: The new laser procedure is considered much safer than the standard procedure. As the laser has already spliced the lens, there is less need to use the ultrasound probe (A 40 percent reduction in the use of ultrasound energy was noted in the study). It must be remembered that the excessive use of ultrasound energy in hard cataracts can sometimes create too much heat and damage the corneal endothelium and other surrounding tissue. Also, as the laser also can create a multi-planar zigzag pattern for the incision in the cornea, it allows the incision to self-seal and decreases the risk of infection.
Quality of vision: It was also found that the new laser procedure produced more improvement in the visual acuity as compared to the traditional approach.
All in all, the new laser procedure for the treatment of cataract could make capsulorhexis less dependent on surgical skill and allow for greater consistency, safety and quality. However, more research and studies are needed to determine if laser-treated patients have better outcomes and also to determine improvements in vision with various types of intraocular lenses. In addition, the new technology requires longer time than the current traditional procedure, and is also more costly. Therefore, more research definitely needs to be done in the near future to fully address and improve these areas as well.