An Nd:YAG laser optimized for use in the both the anterior segment and the posterior segment i.e. vitreous chamber, is recommended for use in Laser Floater Treatment. In order to visualize the floater and target accordingly, the laser’s light source must be positioned in the same optical axis as the ophthalmologist’s visual axis. Most conventional YAG lasers, in contrast, use a lower angle of illuminating light. Whilst these lasers are well suited to use in the anterior part of the eye, they are ill equipped for use in the vitreous chamber and thereby make it difficult for the ophthalmologist to visualize (and treat) floaters.
It is important to note that the laser energy applied during Laser Floater Treatment does not simply break the floater into smaller pieces. Instead, the laser energy converts the floater material to a gas, which is then reabsorbed into the eye.
Using a laser lens placed on the patient’s eye, the YAG laser is focused onto the front surface of the floater. This laser emits a short 3 nanosecond (0.000000003 seconds) burst of energy, which creates a small plasma-state “bubble”. (Plasma, which is the fourth state of matter following 1. Solid, 2. Liquid, and 3. Gas, occurs when the electrons are pulled away from their usual location, creating a high-energy state of the matter.) This process converts the treated floater material into a small gas bubble.
Unlike LASIK vision correction, which attempts to improve visual acuity, Laser Floater Treatment aims to improve a quality of vision. You are probably already familiar with the eye charts used to compare and record visual acuity. The most common is the Snellen Chart: a series of letters or letters and numbers, with the largest at the top. As you read down the chart, the letters gradually become smaller. This test evaluates a patient’s central vision. There are other aspects of vision, such as peripheral and color sensitivity, which are harder to quantify and test.
In most post-treatment cases, there is often no improvement in recorded (Snellen Chart) visual acuity. The optics of the eye do not change following Laser Floater Treatment. Instead, the procedure aims to remove the visual hindrance caused by the presence of floaters, thereby contributing to a significant improvement in a quality of vision.
On average, most patients can expect a 60-90% improvement in the mass and/or amount of floaters following Laser Floater Treatment. Every eye is different and there are a number of variables that affect the outcome of treatment. Some floaters, for example, are located too close to the retina and cannot be safely treated.
It is also important to note the majority of patients will need to undergo two or three treatment sessions in order to achieve a satisfactory result.
The number of floaters to be treated depends on the type of floater(s) and the laser energy required to treat the floater(s) (that is, to convert the floater material into a gas). During treatment, your ophthalmologist will monitor the level of laser energy used for each shot, as well as the total amount of energy delivered to the eye during treatment. In order to ensure safe, effective treatment with minimal patient discomfort, if these energy levels fall outside a pre-determined range then any remaining floaters will need to be treated in a subsequent treatment session.
In the majority of cases, floaters are situated in the vitreous humor. However, in young patients floaters can be found in the Premacular Bursa area. The Premacular Bursa is an anatomical space found between the vitreous humor and the retina. These floaters are microscopic in size, yet appear to be quite large to the patient because of their proximity to the retina. Unfortunately, the microscopic size of these floaters and their location makes them difficult to both visualize and treat.