Surgical and diagnostic technology

All of the technology on this page is used by and available to Dr Chen at Vision Eye Institute Chatswood. These advanced, state-of-the-art imaging, laser and surgical systems support his cataract and retinal care. Each has a specific job: to measure the eye accurately, to see the retina in detail, or to make surgery more controlled.

Illustration of a modern ophthalmic operating theatre with a surgical console, operating microscope and operating table. — An operating theatre equipped for cataract and retinal surgery. Illustration.

What technology does Dr Chen use to examine the retina?

Dr Chen’s clinic uses ultra-widefield retinal imaging, optical coherence tomography (OCT), OCT angiography (OCTA), ultrasound and visual field testing. Together they show the whole retina, its layers and its blood vessels.

Ultra-widefield retinal image showing almost the whole retina, including the far periphery.

Ultra-widefield retinal imaging (Optos)

Photographs most of the retina in one image, including the far edge where tears and detachments often begin.

Autofluorescence shows stress in the retina’s supporting cells and helps track geographic atrophy and inherited retinal conditions.
Fluorescein angiography shows how blood flows through the retina.

OCT scan: a greyscale cross-section of the macula showing the retinal layers and the central dip of the fovea.

Optical coherence tomography (OCT)

Harmless light waves take cross-section pictures of the retina, a little like an ultrasound scan but with light instead of sound.

OCT angiogram: a fine white network of retinal capillaries around a dark central zone.

OCT angiography (OCTA)

The same scanner maps the retina’s small blood vessels without an injection of dye, which helps with macular degeneration and vein occlusions.

B-scan ultrasound of the eye: a fan-shaped greyscale scan showing the eye wall and optic nerve.

Ultrasound (B-scan)

Looks inside the eye when bleeding or a dense cataract blocks the view, to check whether the retina is attached.

A visual field printout: a circular greyscale map of side vision with the normal blind spot.

Visual field testing

Measures side vision when glaucoma or another condition may also be affecting the eye.

How is the eye measured before cataract or lens surgery?

Your eye is measured with optical biometry, multiple methods of corneal mapping and specular microscopy, so the lens power and surgical plan rest on cross-checked measurements.

Cross-section of the eye with a beam of light along the visual axis from the cornea to the retina, and the axial length marked beneath. — Optical biometry measures the eye along its visual axis, including its length from the cornea to the retina.

Illustration of a colour-coded corneal topography map showing a bow-tie pattern of regular astigmatism. — A corneal map. The bow-tie pattern shows regular astigmatism.

Illustration of an ophthalmic diagnostic instrument with a chin rest and a monitor showing a retinal image, in a bright clinic room. — A diagnostic imaging instrument. Illustration.

Optical biometry (ZEISS IOLMaster 700)

Measures the length and shape of the eye to calculate the power of the lens implant. Its swept-source OCT can measure through dense cataracts, and it shows an image of the centre of the retina to confirm you were looking straight at the target. It also measures the back surface of the cornea, which improves astigmatism planning.

Placido-disc corneal topography

Reads the reflection of illuminated rings from the front of the cornea to map its shape. It also checks the tear film, which must be healthy for accurate measurements.

Scheimpflug corneal tomography

A rotating camera images the cornea in three dimensions, front and back, and measures its thickness. It helps detect keratoconus and plan surgery after laser eye surgery.

Topography with wavefront aberrometry

Measures how light is distorted through the whole eye, separating the cornea from the inside of the eye, and measures pupil size in different lighting. This helps decide who is likely to see well with an extended depth of focus or multifocal lens.

Specular microscopy

Counts the cells lining the back of the cornea. These cells keep the cornea clear, so their health matters before complex or combined surgery.

Anterior segment OCT (AS-OCT)

Optical coherence tomography of the front of the eye, including the drainage angle and the space behind the iris where some lenses sit. It is used for selected eyes, not routinely before cataract surgery.

Retinal acuity meter

Estimates how well the retina could see once a cataract is removed, by projecting letters through clearer parts of the lens. It helps set realistic expectations when a cataract and a retinal condition occur together.

How does Dr Chen make lens calculations as accurate as possible?

Lens power is calculated with latest-generation formulas from several independent measurements, then checked by an experienced, dedicated team in every case, routine or complex.

Step 1

Measure

Several instruments measure the eye independently, so any result that does not fit can be spotted and repeated.

Step 2

Calculate

Lens power is calculated with latest-generation formulas, including specialised methods for eyes that have had previous surgery.

Step 3

Check

Vision Eye Institute is a long-established cataract and refractive surgery practice, and its team has decades of combined experience in lens calculations. Every calculation is checked.

Which eyes need extra care with lens calculations?

Previous LASIK, PRK or other laser vision correction
Previous radial keratotomy
Keratoconus and other irregular corneas
Very high short-sightedness
Very high long-sightedness
Intraocular lens exchange

Which lasers are used in Dr Chen’s clinic?

Dr Chen’s clinic has a pattern scanning retinal laser, a YAG laser and a selective laser trabeculoplasty (SLT) laser.

Illustration of the retina during laser treatment, with a neat grid pattern of small laser spots in the peripheral retina. — Pattern scanning laser places spots in a planned pattern.

Pattern scanning retinal laser

Delivers short pulses in patterns rather than single spots. Treatment is quicker and usually more comfortable than older single-spot laser, with less spread of heat into surrounding tissue.

YAG laser

Clears cloudiness behind a lens implant, makes a small drainage opening in the iris when needed, and is used for YAG laser vitreolysis in selected floaters.

Selective laser trabeculoplasty (SLT)

Lowers eye pressure in open-angle glaucoma.

What technology is used during cataract surgery?

Cataract surgery in Dr Chen’s day surgery uses ZEISS CALLISTO eye digital guidance, the Alcon UNITY Vitreoretinal Cataract System (VCS), a femtosecond laser for selected patients and a high-resolution operating microscope.

Illustration of an eye with a cataract in the operating microscope. Digital guides show the incision sites, a 5.0 mm circle for the capsule opening and a dotted red toric lens axis line at 20 degrees. — Digital guidance in the operating microscope: guides for the incisions, the capsule opening and the toric lens axis. Illustration.

Illustration of the Alcon UNITY Vitreoretinal Cataract System (VCS): a white and navy surgical console with a large touchscreen. — The Alcon UNITY Vitreoretinal Cataract System (VCS), used for both cataract and retinal surgery.

Digital guidance (ZEISS CALLISTO eye)

A reference image of your eye is taken when it is measured. In theatre, the system recognises your eye and overlays guides in the microscope: where to place the incisions, the size and position of the capsule opening, and the exact alignment of a toric lens. No ink marks are needed.

Alcon UNITY Vitreoretinal Cataract System (VCS)

The system that removes the cataract.

Intelligent Fluidics measures pressure and flow in the eye continuously and adjusts in real time.
Intelligent Sentry senses sudden changes in flow and responds within moments to keep the front of the eye stable.
4D phaco uses a gentle multi-directional ultrasound movement to break up the cataract efficiently.
Thermal Sentry monitors heat at the incision and adjusts the ultrasound to protect the cornea.

Femtosecond laser

For selected patients, a laser creates the incisions and a round capsule opening and softens the cataract before it is removed.

Femtosecond laser cataract surgery

Operating microscope

A high-resolution surgical microscope with coaxial illumination gives a bright, stable red reflex, the orange glow that shows the lens capsule clearly.

What technology is used during retinal surgery?

Retinal surgery (vitrectomy) uses the Alcon UNITY Vitreoretinal Cataract System (VCS) with a cutter that works at up to 30,000 cuts per minute, stitchless 23, 25 or 27 gauge instruments, ZEISS RESIGHT wide-angle viewing and laser, freezing, dye and gas or oil treatments inside the eye.

Cross-section of the eye during vitrectomy: a fine cutter and a light pipe enter through small ports in the white of the eye behind the lens, with an infusion line, removing vitreous gel. — Instruments enter through tiny ports in the white of the eye, behind the lens.

Alcon UNITY Vitreoretinal Cataract System (VCS)

Dr Chen’s vitrectomy platform. Its HyperVit cutter works at up to 30,000 cuts per minute. Faster cutting means each cut takes a smaller bite of the vitreous gel, which is designed to reduce pulling on the retina. The system controls pressure inside the eye throughout, and the same system is used for cataract surgery.

Small-gauge, stitchless surgery

Instruments pass through tiny self-sealing openings of 23, 25 or 27 gauge, about 0.6 to 0.4 mm across. Stitches are rarely needed.

Wide-angle viewing (ZEISS RESIGHT)

Lets Dr Chen see to the far edge of the retina during surgery, where tears are found and treated.

How is the retina treated during surgery?

Curved and illuminated laser probes seal retinal tears. Diathermy controls bleeding. Freezing treatment (cryotherapy) and a head-mounted laser treat tears far forward.

Dyes, heavy liquids, gas and oil

A specialised dual dye makes fine membranes visible for peeling. Heavy liquids, gas and silicone oil flatten and support the retina.

Gas and oil after vitrectomy

What options are there for complex lens problems?

Dr Chen can offer any intraocular lens commercially available in Australia, piggyback lenses, custom-made high-, low- and negative-power lenses, and specialised instruments for lens exchange and scleral fixation.

Every lens available in Australia

Dr Chen is not tied to any single manufacturer, so the advice is tailored to your eye.

Lens choices

Piggyback and custom lenses

Piggyback lenses such as the Sulcoflex and 1stQ AddOn can sit in front of an existing implant. Custom-made lenses suit eyes outside the standard range: high-power lenses for very long-sighted eyes, and low-power or negative-power lenses for very high short-sightedness (myopia). Dr Chen has extensive experience in cataract surgery for very short-sighted eyes and regularly uses custom-made lenses made to each patient’s measurements.

Lens exchange and fixation

Specialised microsurgical forceps handle and remove lens implants. Dedicated equipment supports the stitchless Yamane technique and sutured scleral fixation.

IOL exchange and complex cataract

Why is it useful that the clinic and day surgery share a building?

Dr Chen’s clinic (level 3) and the day surgery (level 4) share one building, so assessment, surgery and follow-up happen in one place, and urgent surgery can sometimes happen very soon after assessment.

Cutaway illustration of two floors: the day surgery on level 4 with an operating theatre and recovery area, and Dr Chen’s clinic on level 3 with consultation, imaging and waiting areas, joined by a lift. — Dr Chen’s clinic on level 3 and the day surgery on level 4, joined by a lift. Illustration.

Quicker access to surgery when it is urgentFor some urgent problems, such as certain retinal detachments, Dr Chen may be able to operate soon after your assessment, occasionally on the same day. This depends on theatre, anaesthetic and nursing availability, so it cannot be guaranteed, but being in the same building makes it possible more often.
One place for your whole journeyConsultations, scans, surgery and follow-up visits happen at the same address.
Your information stays togetherThe measurements used to plan your operation are taken by the same team, in the same building, as the surgery.
Simpler arrangementsOne team coordinates your clinic appointments and your surgery booking.
Easier for family and carersOne familiar place to drop you off and collect you. Chatswood station is a short walk away, with parking across the road at Chatswood Chase.
Prompt review if something worries youDr Chen works one floor away, so a concern after surgery can be reviewed quickly.
Familiar surroundingsMany people find surgery less daunting in a place, and with a team, they already know.

Dr Chen also operates at Chatswood Private Hospital.

Common questions about the technology

Is all of this technology available in Dr Chen’s practice?

Yes. All of the technology on this page is used by and available to Dr Chen at Vision Eye Institute Chatswood.

What does OCT stand for?

OCT stands for optical coherence tomography. It uses harmless light waves to take detailed cross-section pictures of the retina, a little like an ultrasound scan but with light instead of sound. OCT angiography (OCTA) uses the same scanner to map the retina’s small blood vessels without an injection of dye.

What is the Alcon UNITY VCS?

The Alcon UNITY Vitreoretinal Cataract System (VCS) is the surgical system Dr Chen uses for both cataract and retinal surgery. It controls pressure inside the eye in real time, and its vitreous cutter works at up to 30,000 cuts per minute.

Can surgery happen on the same day as my assessment?

Sometimes, for urgent problems such as certain retinal detachments. The clinic and day surgery are in the same building, but same-day surgery depends on theatre, anaesthetic and nursing availability and cannot be guaranteed.

Does advanced technology guarantee a better result?

No. Good equipment supports careful surgery, but results depend on the eye, the condition and surgical judgement. Dr Chen will explain what is realistic for your eye.

Where can I read more about this equipment?

The manufacturers publish technical information for readers who want more detail. Dr Chen will explain which of these are relevant to your eye at your consultation.

Need urgent eye care?

For new flashes, suddenly increased floaters, a shadow or curtain, or sudden loss of vision, see the urgent assessment advice.

Clinic appointments: (02) 9424 9999

Urgent assessment advice Request an appointment with Dr Chen