It has been quite some time since our last blog post due to a great deal going on at BMC! Alongside some new product releases, we recently made a few adjustments and updates to our ophthalmic imaging instrument, the Adaptive Optics Scanning Laser Ophthalmoscope (AOSLO) which we are releasing early next year.
This next-generation instrument allows in vivo retinal imaging on a cellular level and is currently undergoing beta testing at the Beetham Eye Institute at Joslin Diabetes Center, led by Dr. Jennifer Sun and her team. There it is being used to directly quantify features such as cone density, microaneurysm size and measure blood flow through the microvasculature in the retina. By pairing a Scanning Laser Ophthalmoscope (SLO) with advanced Adaptive Optics, it offers the advantage of imaging the retina at a resolution 2-3 times that of a standard SLO.
The AOSLO is also capable of measuring various properties of retinal cone physiology. Due to its enhanced imaging and software, it enables evaluation of the following attributes:
- Cone Density
- Nearest Neighbor Distance
- Voronoi Tessellation Tile Area
- Effective Radius
- Packing Factor
The AOSLO’s ability to measure such features allows early stage detection of visual decline due to diabetes. This can be identified by the decrease in cone regularity, cone mosaic changes, cone reflectance and a decrease regularity of cone spacing. This function of the AOSLO can help determine early treatment plans for patients and generate further investigative studies.
When testing out the AOSLO at Joslin, we found something very interesting out about our CEO, Paul Bierden. The pictures below depict his own retina, discovering that he has a microaneurysm! This was unexpected news, since normally it would be undetectable by any other retinal imaging systems. 30% of the microaneurysms imaged using the AOSLO at Joslin were not visible in fundus photos. The AOSLO is able to accomplish this by evaluating the vascular and neural retinal planes in vivo with cell-scale resolution. The pictures below also point out the microaneurysm attributes that can be measured. They are:
- Presence of lumen clot
- Wall reflectivity
Lastly, the AOSLO is able to measure small-vessel blood flow. This is done with the help of its enhanced imaging qualities, instrument optimization and post-processing software. By stopping a horizontal scan over a blood vessel, it can measure the blood velocity by tracking the moving erythrocytes over a scanning line. With this information, researchers can produce a blood velocity profile for retinal vessels. See the video below to see how it’s done!
If you have any interest in using the AOSLO, let us know! Please give us a call and let us know about your research. We are accepting orders for the new instrument and are open to collaborative grant applications to secure funding. If you are interested in seeing the AOSLO in action, we are setting up appointments now for the next few months. We hope to hear from you soon!
We received notice yesterday that an Adaptive Optics Optical Coherence Tomography device for retinal imaging built by Lawrence Livermore National Labs won a 2010 R&D 100 Award!
Why do I mention this?
Because our Multi-DM is a central wavefront correcting component in the system. For those of you looking for nitty-gritty details, this is a single-deformable mirror system with a Badal optometer used for low-order corrections. The DM is 140 actuators with an aperture of 3.3mm x 3.3mm and stroke of 1.5 microns (wondering what these terms mean? Refer to this previous post for definitions and our website here for more on the mirror model). Check out the other award-winning inventions at the link below.
Congrats, guys and we’re looking forward to the awards dinner later this year!
Picture: Retina in 3D shown with 3-micron resolution, smaller than most eye cells.
Link for more information: https://publicaffairs.llnl.gov/news/news_releases/2010/NR-10-07-02.html
Update: We're on TV! Check out the video below from ABC 7 News in San Francisco:
This year at the Association for Research in Vision and Ophthalmology (ARVO) Annual Meeting, there were some notable differences from past years. There was a shift in focus in the use of adaptive optics from talking about the technology to making discoveries. Here are the two major indicators:
Adaptive Optics is leaving the Title Page
In past years, there has been amazing research produced from the labs the likes of Roorda, Burns and Williams. But, you'll have to admit that for many of these studies the big "wow" in using adaptive optics for imaging the eye has been the technological innovation and the impressive science and not necessarily the clinical applications. One indicator of this change is the fact that until this year, most of the papers presented at ARVO which used adaptive optics contained the term "adaptive optics" in the title and not just the abstract. This year, that number dwindled significantly as the main focus shifted away from coolness factor. Whether it be new discoveries of cone structure properties with subjects which have genetic mutations or realizations about different types of color blindness, it is now the science and the promise of clinical applications that is center stage and not the technology.
Posters and presentations are showing fewer optical layouts
I spent three days last week at ARVO reaching out to the community and listening in on what is new and interesting. I found it difficult to figure out which mirror was used in any given experiment. This is simply due to the fact that most of the presentations and posters did not specifically call out what equipment was used in their research. As much as this made my job a little more difficult, I welcome this progression. It means that AO is becoming just another piece of equipment rather than a unique addition.
I welcome you to visit the ARVO site and type "adaptive optics" into the keyword finder. There, you'll discover all of the interesting research that is going on in the industry related to our mirrors. The main takeaways that I had from the show:
Precision+stroke = success
The removal of higher-order aberrations is most often paramount in obtaining high-quality images. However, while low-order aberrations can be removed with fixed optics, increased stroke is key to convenience and in some cases, performance. To that end, more and more woofer-tweeter systems (using two deformable mirrors: one long-stroke, low precision and the other short-stroke, high precision) are being used to obtain great images. Check out the upcoming June issue of Photonics Spectra for a byline article on the topic.
Two-photon: The next frontier in vision science?
While there were very few groups using this two-photon fluorescent microscopy, this is a discipline that I found very interesting and I think it could be a new avenue beyond scanning laser ophthalmoscopy (SLO) and optical coherence tomography (OCT) for retinal imaging.
Until recently, the only way to image a large region of the eye and gain any perspective on where you were imaging was to use a fundus image and take the small-area images from the AO imaging system and line them up with key features: Not an easy task. This year, Steve Burns unveiled his newest instrument where he was able to scan over multiple areas using an adaptive optics SLO and create a composite wide-field image of the retina. While this task is equally difficult, it offers a new exciting approach to this process and holds promise for advances in imaging the retina.
A major area of research using adaptive optics is retinal imaging. And, with that interest, BMC has been fortunate to participate in the advancement the field by improving imaging techniques through the use of deformable mirrors. We have been directly or indirectly involved in many types of research.
In this post we will focus on our recent project in collaboration with Dr. Steve Burns at the University of Indiana to build an AO SLO system for use in a clinical setting. This project began as a National Eye Institute grant and has developed into a company endeavor to include our technology in a commercially available instrument that can be used for the early detection of such eye diseases as Diabetic Retinopathy and Age-related Macular Degeneration (AMD). Dr. Burns is putting the final touches on a device for use by clinicians. Pictures of the demonstrated ability to image retinal vasculature through the use of AO and the latest version of the instrument (with graduate student Zhangyi Zhong for size reference) are shown below. Also check out our Facebook page to view a video of the instrument in action: http://bit.ly/9w2y9x
Individual Nerve Fibers can be seen Crossing over a Superficial Blood Vessel:
Vessels down to the smallest Capillaries can be imaged:
We are currently accepting applications for the use of this device for research on the early detection of eye diseases and enabling treatment to slow down or prevent the spread of disease. Please contact us if you are interested in using this instrument as we are anxious to enable new research that can help to stop the progression of debilitating eye diseases.
We will be sure to keep the imaging community updated on the progress of this research and offer glimpses into what is being discovered using the instrument and what it means for eye care in the future.