Myopia, commonly known as nearsightedness, is a vision condition where close objects appear clear, but distant objects look blurry. This occurs when the eyeball grows too long from front to back, or when the cornea, the clear front surface of the eye, has too much curvature. Light entering the eye then focuses in front of the retina instead of directly on it, causing blurred distance vision. While standard glasses or contact lenses can correct this blur, specific medical devices are designed to slow down the progression of myopia in children and adolescents.
Specialized Contact Lenses for Myopia Management
Specialized contact lenses offer a way to manage myopia progression by altering how light focuses on the retina. One approach involves orthokeratology, or Ortho-K, which uses gas-permeable contact lenses worn overnight. These lenses gently reshape the cornea while a person sleeps, flattening its central curve to correct vision temporarily. When the lenses are removed in the morning, the cornea retains its new shape, allowing for clear vision throughout the day without glasses or contacts. This reshaping also creates a specific peripheral light focus that signals the eye to slow its elongation.
Another type of specialized contact lens is multifocal soft contact lenses, which are worn during the day. These lenses feature different zones of optical power across their surface. A central zone corrects distance vision, while surrounding zones introduce a controlled amount of blur in the peripheral vision. This specific optical design, often referred to as peripheral defocus, is thought to reduce the signal for the eye to grow longer, thereby slowing myopia progression. These daily-wear lenses provide clear central vision while working to manage the underlying cause of increasing nearsightedness.
Advanced Technology Spectacle Lenses
Advanced technology spectacle lenses provide an alternative for myopia management, differing significantly from standard single-vision glasses. These lenses incorporate unique optical designs to influence how light enters the eye and focuses on the retina. Unlike traditional lenses that correct central vision uniformly, these specialized glasses aim to manage the growth of the eye. They achieve this by creating specific light patterns on the peripheral retina, which can signal the eye to slow its elongation.
One common design, known as Defocus Incorporated Multiple Segments (D.I.M.S.) technology, features a central optical zone for clear distance vision. This central zone is surrounded by hundreds of small, non-corrective lenslets that create a constant level of peripheral defocus. Similarly, Highly Aspherical Lenslet Target (H.A.L.T.) technology also employs a central clear zone for sharp vision. Around this central area, a series of highly aspherical lenslets are precisely arranged to generate a volume of light that falls in front of the retina in the periphery. Both D.I.M.S. and H.A.L.T. lenses provide clear central vision and a specific peripheral light focus, which is believed to reduce the stimulus for the eye to grow longer.
At-Home Light Therapy Systems
At-home light therapy systems represent an emerging category in myopia management, focusing on the use of specific light wavelengths to influence eye growth. These systems typically involve devices that emit low-intensity red light. Users engage in brief, repeated sessions, often lasting a few minutes each day, where they look directly into the light source. The proposed mechanism for these systems involves the stimulation of the choroid, a vascular layer of the eye that provides nutrients to the retina.
The specific wavelengths of red light, commonly around 650 nanometers, are thought to enhance the thickness and blood flow within the choroid. An increased choroidal thickness is often associated with slower eye elongation, which is the primary cause of myopia progression. While research is ongoing to fully understand the long-term effectiveness and optimal treatment parameters, initial studies suggest that these light therapy systems may offer a non-invasive method to help slow the progression of myopia. As a newer technology, their availability and regulatory approval can vary by region.
The Process for Obtaining Myopia Devices
Obtaining myopia management devices involves a structured process that begins with professional consultation and assessment. The first step requires a comprehensive eye examination by an optometrist or ophthalmologist specializing in myopia management. During this visit, the eye care professional evaluates the child’s current vision, eye health, and the rate of myopia progression to determine the most suitable treatment option, discussing various device options tailored to individual needs and lifestyle.
Following the initial assessment, a specific fitting process is undertaken for the chosen device, whether it be specialized contact lenses or advanced spectacle lenses. For contact lenses like Ortho-K, this involves precise measurements of the corneal curvature to ensure a custom fit. Spectacle lenses also require accurate measurements to align the specialized optical zones correctly with the wearer’s gaze. Regular follow-up appointments are typically scheduled every few months to monitor the effectiveness of the device, assess eye health, and make any necessary adjustments to the prescription or device type.