There are two realms of information when assessing ocular health: the structure of the various components of the eye and the functioning of the visual system. Like many things in life, there are many variations on what a normal eye can look like – sometimes healthy eyes can appear entirely unhealthy. On the other hand, ocular pathology can sometimes be subtle and difficult to detect. At times only the best in analytic instrumentation can make the distinction between normal and diseased eyes. Because technology matters, Beartooth Vision Center offers the best to our patients in both structural and functional testing.
This is an important distinction between primary care private optometric practices such as ours and the abundance of retail and store – based optometry offices in Billings. Square footage matters: Retail optometry exists so the chain store can sell eyeglasses. Because of this, commercial stores do not dedicate valuable floor space to primary care diagnostic instrumentation that is deemed by them to be unnecessary. At Beartooth Vision Center, we consider leading edge technology vital to the quality of care we provide our patients.
We recommend the Daytona as part of our annual eye examinations. We also use it to trouble shoot when our patients have symptoms of vitreous or retinal problems. Based on what we see with the Daytona, we are able to “zoom in” on the problem with other scanning diagnostic laser technology if needed. (See Heidelberg OCT below). – Dr. Currence
Following is a quote from the Optos web site about the Daytona instrument:
“From the 200 degree view of the retina in one image, captured in less than one second to the multiple imaging modalities available, the Daytona brings the benefits of ultra-widefield Optomap images to your practice, inside a compact design … Daytona is capable of on-the-fly, ultra-widefield imaging in color, red- free, and auto fluorescence, providing views of deeper structures of the retina … Daytona was engineered with patient comfort in mind. Our ergonomic design encourages a neutral body posture and simple positioning of the eye.” Learn More >>>
Heidelberg Spectralis Ocular Coherence Tomographer (OCT) with Multicolor
We decided on a Heidelberg Spectralis OCT because it is a combination of 2 diagnostic confocal scanning lasers which work together to provide unparalleled clarity, precision, and ease of use for both the patient and the operator of the instrument, as well as the ability to scan exactly the same place in the eye when monitoring for small and microscopic changes over time. This is essential for the diagnosis and monitoring of conditions such as glaucoma and macular degeneration. The Multicolor scanning laser image is a very detailed picture of the retina that can be broken down into 3 retinal layers. Our OCT has excellent analytical software for clinical decision making and we also benefit from software updates that further expand the capabilities of this remarkable instrument. – Dr. Currence
Following is a quote from the Heidelberg web site:
Multi-modality imaging with SPECTRALIS® is helping drive the development of novel therapeutics and changing the course of patient management in eye care. Using an upgradeable platform approach, SPECTRALIS has enhanced the role of spectral domain OCT by integrating it with confocal scanning laser ophthalmoscopy (cSLO). The combination of these two technologies has enabled new imaging capabilities, such as TruTrack™ active eye tracking, and BluePeak™ blue laser autofluorescence, providing clinicians with unique views of the structure and function of the eye.
Enhanced anatomical details, 1 micron measurable change1 and automatic rescan at follow-up are the direct benefits of TruTrack™ active eye tracking and simultaneous dual-beam imaging. These two technologies are at the core of the SPECTRALIS product platform. Enhanced image detail comes from Heidelberg Noise Reduction™, which improves images like Dolby® noise reduction improves recorded sound. Measuring change with 1 micron reproducibility is possible with AutoRescan™, which automatically places follow-up scans in precisely the same location, bypassing operator variability. This precision is the product of 20 years of proven HRT technology, which paved the way for the dual-beam approach to imaging. Learn More>>>
Heidelberg Spectralis Ocular Coherence Tomographer Angiography (OCTA)
Diopsys NOVA VEP and pERG
The Visual Evoked Potential (VEP) test measures the total speed of the electricity in the visual system. Although it varies somewhat, a healthy eye and optic nerve take about 100 miliseconds (1/10 second) for the biological electricity to reach the brain. This is about 5 ½ miles per hour. The amount of electricity produced varies significantly over this brief amount of time, with peaks and valleys on the Diopsys printout much like the variations of an EKG.
The pattern Electroretinogram (pERG) test targets the electrical activity at the retina and ganglion cell layer of the retina – typically 2 to 8 microvolts. It is used to help detect, measure and track the impact of retinal conditions such as Wet and Dry Macular Degeneration and medicine toxicities on the electrical component of the visual system, as well as to diagnose and monitor the effects of glaucoma.
Eyes that are diseased because of electrical problems have a Diopsys VEP and pERG printouts that looks significantly different than a printout from healthy eyes. Electrical production problems (macular degeneration or other retinal conditions) or optic nerve transmission problems (such as glaucoma, optic atrophy, or Multiple Sclerosis) diminish the amount and speed of the electricity throughout the entire eye and at the retinal level as well.
The Diopsys NOVA VEP and PERG instrument is a game changer in our ability to detect and treat certain eye problems at their earliest stages when the subtle electrical functioning of the eye is just beginning to go downhill. The Diopsys instrument is the perfect functional compliment to the OCT scanning laser technology. It provides sound objective measures of how well eyes are working and allows the measurement of decreased ocular functioning in the same early time frames as the structural damage that are measured with our Heidelberg OCT. The combination of these two technologies will hopefully result in a more complete understanding of disease processes within the eye and earlier treatment intervention, as well as determining if those treatments are effective.
Following is a quote from the Diopsys web site:
The Diopsys® NOVA-LX Vision Testing System is a part of the Diopsys® NOVA-VEP suite of tests which use a technology called Visual Evoked Potential (VEP) to objectively measure the functional responses of the entire visual pathway from the anterior segment of the eye to the visual cortex. By using VEP, the device provides quantitative information to support the interpretation and management of eye and vision deficits, and reports and documents the results of practitioner intervention for tracking patients’ response. It is easy to use, non-invasive, and provides a quick qualitative analysis of the VEP waveform and easy quantitative analysis of the amplitude (strength) and latency (speed) values.
Eye care specialists may test children six months of age and older, patients with a degenerative process such as glaucoma or multiple sclerosis (MS), or patients following a neurological event like traumatic brain injury (TBI) or stroke in order to help the clinician detect visual deficits such as optic nerve disorders, amblyopia, and other neuro-visual disorders.
The Diopsys® NOVA-ERG Vision Testing System is an office-based pattern electroretinography (pERG) module – a part of the Diopsys® NOVA suite of tests. The pERG is an evoked potential test that measures the function of the retina. Patients view a screen with alternating checkerboard patterns to elicit a pERG response. Pattern electroretinography helps doctors gain objective information about the performance of the inner retinal cells of the eye, especially in an area of the retina called the macula. This information can help optometrists and ophthalmologists diagnose and monitor vision disorders like glaucoma, macular degeneration and diabetic maculopathies.
“The Diopsys® NOVA-ERG is an important addition to the Diopsys® NOVA suite of tests. In one sitting, an eye care specialist can objectively measure the function of the patient’s retina while also measuring the function of the entire vision system, from the eye to the visual cortex,” said Dr. Alberto González, Diopsys Research Director, “This will help doctors objectively distinguish between retinal and cortical pathway issues.” Learn More>>>
Humphrey and Heidelberg Visual Field Analysers
Our Humphrey and Heidelberg Engineering visual field analysers are the gold standard for measuring the peripheral visual field. In healthy eyes, the peripheral vision (also known as “side vision”) remains the same in size throughout life. There are medical conditions such as glaucoma, stroke, and space – occupying lesions inside the brain which can cause complete or partial loss of sensitivity of the peripheral vision called an absolute (complete) or relative (partial) scotomas. We have used both of these instruments to detect significant medical problems and both will continue to be valuable diagnostic tools at Beartooth Vision Center. – Dr. Currence
Following is a quote from the Humphrey web site:
Validated by more than 25 years of research, design and clinical experience, the Humphrey Field Analysers is the accepted standard of care in glaucoma diagnosis and management. With over 65,000 installed units worldwide, the Humphrey Field Analysers is the premier automated visual field perimeter.
Following is a quote from the Heidelberg Engineering Web Site:
Visual field testing remains the main diagnostic tool to provide information about a patient’s visual function, quality of vision and quality of life. Functional testing supports clinicians in early disease detection, staging of disease or trend analysis I progressive glaucoma. HEP 2 – in – 1 perimetry offers the most appropriate test for each stage of disease. It offers the right stimulus to your patient at the appropriate stage of disease.
Reichert Ocular Response Analyzer G3
The addition of the Reichert Ocular Response Analyzer G3 provides our office the ability to understand even better the nuances and dynamics of glaucoma. Corneal hysteresis is a measure of the behavior of the eye in that it measures how a cornea responds to an outside pressure. It is essentially a measure of the elasticity of an eye. Some eyes are very elastic (like a balloon) and can absorb a higher internal pressure with no damage. Other eyes are far more rigid (like a glass bottle) and are much more likely to have damage with a higher pressure inside. The Reichert Ocular Response Analyzer G3 is a very good predictor of who is at risk of developing glaucoma and also how well our glaucoma patients are responding to their medications. – Dr. Currence
The Ocular Response Analyzer® is uniquely positioned as the only tonometer that can measure corneal hysteresis, a superior predictor of glaucoma progression. Corneal hysteresis is an indication of the biomechanical properties of the cornea differing from thickness or topography, which are geometrical attributes. “Corneal hysteresis measurements were significantly associated with risk of glaucoma progression. Eyes with lower corneal hysteresis had faster rates of visual field loss than those with higher hysteresis. Reichert’s automatic, non-linear pressure ramp customizes the air pulse, in real time, for each eye being measured. This patented feature enables the softest possible air pulse, ensuring maximum patient comfort. – as quoted on the Reichert website.
Marco / Nidek OPD-Scan III
The Marco / Nidek OPD-Scan III instrument has brought waveform technology to Beartooth Vision Center. This instrument measures a wealth of information about the patient’s refractive status, including corneal topography (contour mapping of the clear tissue on the front of the eye), a person’s glare and blur simulations, and an aberrometer which measures the higher order aberrations (HOA’s) of the eye. For the first time in the United States, we have added the fitting software from the Waveform contact lens company to our OPD-Scan III to create a powerful problem-solving device for many of our patients who have special visual needs. The Waveform company manufactures highly precise custom wavefront guided soft contact lenses and multifocal contact lenses. With the fitting of Waveform contact lenses, Beartooth Vision Center has entered the cutting edge area of correction of higher order aberrations (HOA’s). There are about 80 different types of HOA’s. These are imperfections of light that occur as light goes through the pupil and different interfaces of the eye on the way to the retina in the back of the eye. Traditional glasses and contact lenses do not correct this blur that everyone has to one extent or the other.
The amount and impact of HOA’s vary widely from person to person. Some people have fewer HOA’s, with little effect on their vision. Other people have significant HOA – related visual problems, including glare and reduced clarity in low light and at night. People with degenerative corneal conditions (such as Keratoconus and Pellucid Marginal Degeneration) can experience significant distortion and blur of their vision under any lighting conditions – even with traditional glasses or contact lenses – due to an extreme amount of HOA’s from the corneal irregularities. With the incorporation of a precise “HOA fingerprint” custom soft contact lens correction compensated to align perfectly with the position and fit of the contact on the cornea, Waveform custom soft contacts can be life changing. These contact lenses are truly unique and custom made for our patients. Waveform contact lenses can provide far better visual clarity for these people, as well offering an alternative vision correction for people with very high prescriptions that create significant visual distortion with conventional lens technology. – Dr. Currence
Following is a quote from the Waveform web site:
Over the past 15 years, new high-tolerance objective measuring technology called “wavefront aberrometry” has been developed. Conventional eye exams measure low order (2nd order) optical aberration—sphere, cylinder and axis and, in the case of a presbyope, the addition power. Through advancements in LASIK surgery, wavefront aberrometry was developed to optimize the visual outcome. Wavefront aberrometry is an advanced 21st century optical measuring technology that measures 28 levels of aberrations within the human eye, called Zernike coefficients. Only one of these levels—2nd order aberrations—are measured in conventional subjective refractions today. An aberrometer is capable of taking advanced, objective and complex optical measurements of the human eye in seconds, compared to the typical 15 minute subjective eye exam.
Optical aberrations are defined as anything that causes light to bend and can change significantly as the pupil dilates under low light conditions, such as at night. This is why many people are happy with their vision during daylight hours and then are uncomfortable and complain about their vision at night. The important optical aberrations that affect vision are:
- 2nd Order optical aberrations – currently measured in all eye exams providing sphere, cylinder and axis corrections
- 3rd and 4th Order optical aberrations – high order aberrations currently not measured in today’s eye exams but can account for up to 20% of the eye’s refractive error.
- 5th and 6th Order optical aberrations –also high order aberrations not currently measured in today’s eye exam. These aberrations are of less significance clinically, however they manifest in reduced vision for a small percentage of eyes.
Uncorrected high order aberrations (HOA’s) can lead to poor nighttime vision, a reduction in depth of focus for reading, glare around lights at night and reduced color perception. All of these HOA’s manifest in varying degrees for each individual patient. Pupil size is a significant contributor to the manifestation of high order aberrations. As the pupil increases in size, more peripheral light enters the eye. As a result, a blur circle is created instead of a point focus on the retina. As the blur circle increases in size and shape, visual clarity is diminished. This is why even some patients with 20/20 vision can complain of visual discomfort.
Wavefront aberrometry has been commercially available for over 10 years. Its primary use, when originally introduced into the optical industry, was to provide optical measurements that could aid the refractive surgeon improve the vision outcome for LASIK. The aberrometer shines a perfectly shaped wave of light into the eye and captures reflections distorted based on the eye’s surface contours. Thus, it generates a map of the optical system of the eye, which can be used to prescribe a solution, correcting the patient’s specific vision problem.
Over the past four or five years, this technology has greatly improved optometrists and ophthalmologists’ ability to develop more precise and specific prescriptions. By using the wavefront aberrometer, they have helped many patients achieve a much higher standard of vision.
WaveForm has developed two technologies that utilize advanced wavefront aberrometry measurements to improve the eye exam experience called “Optimized WaveFont Refraction,” the patient and eye doctor can provide a customized correction of each individual’s low and high order optical aberrations through the manufacture of wavefront-guided soft contact lenses.
WaveForm’s wavefront-guided contact lens technology and optimized wavefront refraction for eyeglass lenses address the problem of uncorrected high order aberrations in different ways.
- For WaveForm’s wavefront-based objective eye exams, the optimized wavefront refraction incorporates all low and high order aberrations to produce an optimal low order prescription in seconds. Since the eye moves behind the eyeglass lens, it is virtually impossible to correct for the optical fingerprint on the surface of eyeglass lenses.
- In the case of WaveForm’s wavefront-guided contact lens technology, the individual optical fingerprint is generated on the surface of the soft contact lenses and placed directly on the eye’s surface, thereby fully correcting this unique optical fingerprint.
Beartooth Vision Center glasses lenses are made in Helena, Montana. Summit Optical is a small privately owned lab that makes glasses lenses for private optometric practices located primarily in Montana. Summit Lab has consistently done superior quality work in a prompt fashion and has an in house state – of – the art antireflective lens coating facility that applies the top rated glare reduction coating in the industry. Their work is superior.