ZEISS’s ultra-widefield retinal camera is finding a home in optometry practices and ophthalmology clinics across the country. Insight explores how it’s being used in both settings, underpinned by advanced software.
In 2003, after moving from Ireland to Australia with his young family, optometrist Dr David Shanahan opened a boutique practice in Fremantle, Western Australia, a location he continues to occupy today under the name David Shanahan Optometrists.
He kitted out his rooms with the best equipment, with a retinal camera being a top wish list item when they became available around 2006. A couple of models have served him well over the years, but nothing has come close to the resolution and widefield view he can obtain with the ZEISS Clarus 500.
Since becoming available in 2018, the instrument has developed into a must-have device in independent optometry practices across the country. It’s a staple in ophthalmology clinics too, where specialists are making highly informed clinical decisions thanks to its availability on the ZEISS Retina Workplace, powered by Forum.
At David Shanahan Optometrists, the Clarus 500 was installed in 2019 as part of a broader investment in a suite of ZEISS devices and software.
Dr Shanahan says ultra widefield imaging is becoming increasingly commonplace in optometry, knowing that indications of disease are often located in the far periphery of the retina.
One of the big advantages with the Clarus 500 instrument, according to its manufacturer, is that it allows clinicians to use colour to their diagnostic advantage.
The device generates images that closely resemble the colouration of the fundus as seen during clinical examination, aiding the diagnosis and documentation of ocular disease, and instilling confidence when evaluating the optic disc, nevi and lesions where colour is important.
Dr Shanahan agrees, but for him one of the most useful functions is the use of IR Preview that allows the user to optimise alignment, intervene with lid and lash, and remove artifacts before capturing an image.
He says it’s akin to a live infrared image that allows the optometrist to assess the retina and identify the target area in “excellent quality” before acquiring the image.
Routinely, each patient’s retina is examined with the slit lamp before jumping on to the Clarus 500 for review in IR Preview and an image is taken, undilated. For patients with suspicious retinal pathology, a more thorough examination takes place on the slit lamp with a retinal lens, and they are dilated before having their eye scanned in multiple positions.
The technology can produce a 133-degree widefield image, which can then be automatically merged to achieve a 200-degree ultra-widefield of view.
“One thing that concerned me with some other retinal cameras was they would provide an oval-shaped image, which is horizontally wide and vertically narrower. When you’re looking for retinal detachments, you’re especially interested in those in the superior retina, they’re the ones you don’t want to miss, and the Clarus is great for that.
“The big reason everyone’s interested in ultra-widefield imaging is that it allows us to photograph a suspect area that you see with your retinal lens or slit lamp, allowing us to document those the lesions in the peripheral retina.
“And sometimes the Clarus has detected retinal detachments in the peripheral retina that weren’t visible on the slit lamp.”
That’s happened a few times, with a notable case involving a patient who is a medical specialist. It couldn’t be seen on the slit lamp but was clearly defined with the IR Preview function before being scanned. A sectional OCT scan over the lesion confirmed the retina was elevated and he was referred and subsequently received laser treatment.
A big part of that diagnosis was the use of the Blue Channel function. Although this is designed to increase visibility of the anterior retinal layers, allowing easier visualisation of the retinal nerve fibre layer and epiretinal membranes, Dr Shanahan has found it serves another purpose in his practice.
“Something that’s not really spoken about is that it’s great for detecting retinal detachments and retinal holes, helping diagnose if a retinal hole is old or new, or if there’s an area of elevated detached retina around the hole,” he says.
“It’s proved useful for detecting and diagnosing how serious a retinal lesion is. Is it just a hole that’s not leaking, or is it a hole with a whole area of retina surrounding it that’s elevated and detaching?”
To ensure he got the most out of his ZEISS equipment, Dr Shanahan went the extra mile and invested in the company’s Forum data management software. It works to provide seamless data integration of various diagnostic devices.
“It puts all the patient data in one place, and it’s easier to share with specialists we refer to; it’s a software that many ophthalmologists have.”
Piecing the patient puzzle
One of those ophthalmologists is Dr Michael Karpa.
The owner and sole ophthalmologist of Best Practice Eyecare, in Caloundra, Queensland, says Forum has been a game-changer for his high-volume clinic that sees a lot of glaucoma, medical retina, and dry eye cases.
After all, one of the biggest challenges for busy ophthalmologists today is not only capturing images and data, but finding ways to compile these into meaningful analyses that balance efficient workflow with an exceptional patient experience.
Dr Karpa has a suite of ZEISS equipment that feeds into the Forum software, one of them being the Clarus 700 that he installed as soon as it became available in Australia.
“Every single piece of patient data I capture, whether it’s from the Clarus 700 or my other ZEISS equipment like the OCTs, visual field machines or slit lamp, it all comes into Forum in a single location. It’s seamless, efficient and patients love it when you’re able to show them what’s going on.
“I’m avoiding the need to run around and check results on different machines, and can make much better and informed clinical decisions.”
Forum is the software powering the ZEISS Retina Workplace. It allows ophthalmologists like Dr Karpa to elevate their practice with software that can align ultra-widefield fundus images with OCT angiography images — all on one screen within seconds.
For example, on the platform users can navigate multiple analyses at the same time; they can review synchronised data such as OCT macular cubes registered with OCT raster scans and fundus images. Pathological changes can also be tracked over time with one click, by comparing three exams on a single screen.
History charts can record treatment decisions over time to help assess effectiveness.
That allows Dr Karpa to track subtle changes in pathology as well as view, compare and annotate images. It’s comprehensive, yet efficient.
After conducting a trial on two leading ultra-widefield systems, access to ZEISS software was a major factor in Dr Karpa’s decision, but not the only one.
The Clarus 700 hardware stood out for two big reasons. Even though his staff were more familiar with another piece of technology, he says they found the Clarus 700 simpler to use from the get-go.
“It gives off a bright flash that patients don’t always like, but other than that we have no difficulty getting them positioned perfectly to acquire an image.
“You can get out to 200 degrees, it does take a few shots, however the image quality is superior – there’s really no comparison. The colour is as close as you can get to the real thing, but it’s the definition that impresses me the most.”
That high-resolution, ultra-widefield image can be captured down to seven microns.
While each patient has a retinal scan to establish a baseline regardless of their case, imaging of the optic nerve head in glaucoma, monitoring of macular degeneration, including geographic atrophy (GA), choroidal nevi, peripheral lesions, lattice retinal tears, and checking the stability of retinoschisis are all common pathologies where the Clarus 700 becomes indispensable.
“It’s also an excellent record for diabetic maculopathy retinopathy; it’s much better than any description I can write.
“Fundus autofluorescence is something we use all time, which is helpful to monitor disease in the retina without any visible changes, and is also useful for monitoring of GA.
“We also perform a lot of fluorescent angiograms (fundus fluorescein angiography) here, and we find the blue channel very easy to use for this.”
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