In February 2024, Alice Springs optometrist JO MURPHY became the first independent optometrist in the world to purchase a Hyperparallel OCT, representing the next generation of imaging technology invented, developed and manufactured in Melbourne by Cylite. He discusses how the device is giving a new edge to his clinical work.
As a full-scope independent optometrist in Alice Springs, Mr Jo Murphy offers the full gamut of services. Specialty contact lens fitting, myopia management and keratoconus examinations make up a major part of his working week. But space is at a premium and it can be difficult to justify investing in a single modality device that, for instance, only measures axial length or scleral topography.
When Murphy’s OCT overheated not long after purchasing Eyecare Plus Alice Springs from longtime owner Mr Bill Robertson in late 2021, initially this was viewed as a setback. He then discovered it couldn’t be repaired, but his fortunes turned when Teacher’s Health in Brisbane offered him a recently retired OCT from one of its practices.
With a stopgap solution in place, in retrospect, the mishap was an opportunity to pay down some debt and bide his time to invest in a system at the cutting edge of OCT technology.
Murphy first saw the Cylite Hyperparallel OCT (HP-OCT) at O-SHOW22 and was immediately impressed by what a true 3D image of the eye could offer and its potential to perform multiple functions. He visited the Cylite head office in Melbourne later in 2022 to trial a prototype and tour the manufacturing facility.
Cylite started taking orders at O=MEGA23 and with the device now commercially available, Eyecare Plus Alice Springs became the first independent practice to purchase the technology. While it has posterior segment capability, it’s the HP-OCT’s anterior segment imaging that’s turning heads across the global ophthalmic industry.
“It has the potential to replace so many machines; anterior and posterior corneal topography, a scleral topographer and biometry as well as full volumetric anterior and posterior OCT imaging, make it ideal for my practice,” he says.
“While specialty contact lenses are a significant part of my work, it’s also difficult for me to find the space and build a financial case for a machine that offers a standalone modality like scleral profiling. Specialty contact lens practices can justify it, but for me the Cylite HP-OCT is a much better proposition.”
The HP-OCT has quickly cemented its place as one of, if not the, key device in Murphy’s equipment suite. Once the normative retinal database is ready and integrated with the system, he expects it to enter a whole new realm.
Scans can be conducted by an optometric assistant and once the image is pulled up in the consulting room, Murphy has a wealth of information he can slice and cut in any direction, X, Y or Z axis – all without any gaps, holes or B-scan stitching artefacts to deal with. It’s something he hasn’t had access to previously.
This is because the HP-OCT offers an industry-leading 302,400 A-scans per second. It can simultaneously image across a wide area of the eye with minimal motion artefacts.
In turn, in one scan, the system captures a full 3D image of the anterior segment. This supports personalised contact lens fitting with highly accurate and repeatable elevation and curvature maps. A full set of biometric measurements, including axial length, supports myopia management. Plus, the same volumetric imaging technique can also be applied to the posterior segment to produce excellent volumetric retinal images.
“What particularly stood out to me is that, with traditional OCTs, they are scanning with one beam of light, so you need to know what you want to capture. If it’s an epiretinal membrane, for example, you need to know beforehand whether a horizontal or vertical scan is going to best document the wrinkle in that particular retina,” he explains.
“Whereas the HP-OCT incorporates a micro-lens array to split the light source into 1,008 individual beamlets – each of which scan a very small area. But these beamlets are scanning at the same time, which makes it less prone to some of the errors that can occur through movement. The HP-OCT then captures and builds a true 3D volumetric model – and you can decide however you want to view that once the scan has been acquired. This is beneficial from an accuracy and patient flow perspective.”
He’s also been impressed with the coverage of the scan. His HP-OCT anterior lens captures a 16.6 mm X 16.6 mm scan, which he says easily captures all that’s required to assess the anterior segment.
For Murphy, it’s enabled him to visualise diseases unlike before. In fact, it took some adjustment. An example of this is pinguecula or a pterygium, a condition that he previously showed patients with a slit lamp camera.
“I thought slit lamp photos were a good way to demonstrate how sun exposure is affecting the front of their eye. But since bringing it up on the HP-OCT image, it seems to have had a more profound impact. Several patients who have ignored my advice for years are now taking sun protection seriously and buying sunglasses with side protection,” he says.
“I’ve found myself referring to an eye model a lot less. Instead, I’m using a single Cylite scan of their own eye where I can show the apex of their cornea through to the back of their crystalline lens. This has been fantastic for explaining diseases and their treatments.”
An elevated level of service
Murphy has spent the last decade working as an optometrist in Central Australia. When he is not working in Alice Springs, he’s often visiting far flung communities performing outreach work, flying the plane himself as a licensed pilot.
Often in these settings, he’s making clinical decisions with traditional equipment, some that may have even become redundant for the modern optometrist. The irony isn’t lost on him that, upon returning to Eyecare Plus Alice Springs, he now has access to one of the latest and unique OCTs on the market.
“The best way we can provide an excellent service is to use all of the tools at our disposal. Sometimes that’s an HP-OCT, widefield camera, meibography or your trusty retinoscope,” he says. “At the end of the day, if you’re trying to make a decision on whether someone requires further assessment, and especially if they are travelling long distances, you want to obtain the most information as possible, so investing in technology is a no brainer.”
The data estimates as many as 1:200 (others are as high as 1:2,000) people have keratoconus, and Murphy believes this prevalence rate matches with his practice.
The HP-OCT, and its ability to capture highly accurate measurements of the topography of each optical surface within the anterior segment, especially shines in these cases. For mild to moderate keratoconus, he believes the system will prove valuable in detection but also monitoring for progression and potential referral for collagen cross linking. In advanced keratoconus, the HP-OCT has excelled because it is tear film independent and is not subject to ring jam like the previous placido disc topographer Murphy used.
“Previously with keratoconus, we had to scan the eye with a corneal topographer, and then move them to our standard OCT, but this was only able to image about six millimetres at a time and just in single line scans. Now we can obtain all of this, plus more, in one scan,” he says.
“I’m hoping that it also leads to more accurate contact lens fitting in keratoconus, with less chair time. I’m still using it in more of a traditional sense, where I might be performing a baseline scan and putting a trial lens on the eye and assessing the post-lens tear film to make modifications to the lens. Previously this would require at least five different scans on the OCT per contact lens. Now I can capture the entire post lens-tear film in a single scan. But there is the potential for this type of technology to enable us to build a lens shape that’s more highly individualised, once the work has been done to link with the lens labs.”
The HP-OCT is also set to offer advantages in myopia management. In 2023, Cylite signed an agreement to integrate PreMO myopia app into its software developed by Professor James Wolffsohn and colleagues at Aston and Ulster universities, helping clinicians to predict myopia onset and progression in their patients, including growth curves.
While Murphy has only used the Cylite to obtain baseline axial length measurements for myopes, he believes the software will inform discussions with parents on the need for treatment and, in future, monitoring its effectiveness.
“Again, it was hard to justify the capital expense or floor space of a machine that measures axial length alone, but to have it incorporated into an existing machine is ideal for our practice,” he says.
User experience
To support its hardware, Cylite has also developed software called Focus. For the practitioner, this is the user interface, and something the company knows it will be closely judged on.
With the bulk of Cylite’s efforts focused on the hardware, it is now beginning to roll out gradually improved software to improve the user experience and to add new features. Murphy has viewed the newest version – in final stages of certification – that he anticipates having shortly with “greatly increased capability”.
“When you consider this machine is capturing a 3D volumetric scan of the eye using OCT technology, the options for what metrics can be extracted and compared over time are seemingly endless,” he says.
“The software developers are conscious of being able to provide a machine with customisable features so that individual practitioners or researchers can extract certain metrics that are useful to them, while also making the interface user friendly. I think they have done this really well and I am excited to see what future development of the software will bring.”
Reference: https://www.insightnews.com.au/first-in-line-for-the-hp-oct/
