The Topcon 3D OCT Mach 2

Chris McMahon
Gold Coast, QLD

When it came to equipping my third practice, the issue was not whether or not to get an OCT, but which OCT to get. Having had OCTs in both my other practices for the past 2 years, I would now find practising without one very inconvenient. It’s like having a retinal specialist in the room with you. In fact, it was a retinal specialist who recommended the Topcon 3D OCT Mach2 to me.
Our patients have also come to expect this level of technology and sophistication in our practices. The OCTs have been great practice builders.
There are major advantages in having an OCT in terms of quantifying things that previously I had to rely purely on appearance, such as nerve fibre layers and their thicknesses, the integrity of the retinal pigment epithelium, the presence of choroidal neovascular membranes and retinal thicknesses at the macula.
I wanted to upgrade to Spectral/Fourier domain technology - this means the instrument records interferometric information with a spectrometer setup rather than with moving mirrors. This results in greater scan speeds (20 000 A scans/ second) and vastly superior image quality. The Topcon 3D OCT has an axial resolution of 5 microns and lateral resolution of 20 microns. 2 dimensional cross sectional scans take just 0.03 seconds. This eliminates any eye movement artefact.
 I also wanted a non mydriatic digital retinal camera. Topcon is in the unique position that it is the only OCT on the market that combines an OCT using Fourier/Spectral domain technology with a retinal camera which produces quality 45 degree fundal images. These can be viewed in full colour or red free.  There is also a mosaic function which can be used in combination with OCT RNFL and RPE scan images.
As I have my support staff performing full pretest routines on all patients, including OCT scans, ease of image capture was high on my list of priorities in choosing the OCT for my new practice.
Image capture for the Topcon3D OCT is based on the simple image alignment utilised in their fundus cameras.  Auto Z- ing is achieved by simply pressing a button next to the joy stick. Image capture is initiated by simply pressing the button on top of the joy stick – no having to deal with a mouse and a joy stick at the same time – something support staff ,in particular, find difficult to master with other OCTs.  This makes teaching someone how to use the Topcon 3D OCT very easy – even my 12 year old son was able to capture good quality images after a few minutes of tuition!
Having a fundus camera combined with an OCT within the one instrument, meant I could save a lot of space in the pretest area. It also meant lining the patient up with only the one instrument rather than two – this saves a lot of time. The unique combination also meant only having to buy one instrument. This saved me money as well. 
In terms of the OCT capabilities, the Topcon 3D OCT has a wide scanning area capability (8.2mm x 3mm) allowing the optic nerve head and the macula to be covered in a single scan. A display depth of 2.3 mm means greater flexibility with optic disc scans. Scans are qualified by age matched data analysis. Fixation targets are changeable and moveable to aid with peripheral scans and low vision patients.
Capturing 3D images of the retina is the most exciting part of current OCTs. The Topcon instrument not only allows all retinal layers to be visualised, but each can be peeled back, moved and cropped, allowing any lesion of interest to be viewed in even greater detail.
One of the greatest advantages of combining a fundus camera with an OCT is that both colour fundus image and OCT image are clearly presented next to one another on the same screen – allowing direct comparison of both images for the lesion or retinal area in question.
Another aspect of the Topcon 3D OCT that I particularly like is its ability to scan, and hence compare, exactly the same area of retina on subsequent visits. You can mark any point and review this anytime in a 3D scan, 2D scan or fundus image.  It also allows you to display subsequent images side by side. This makes following retinal changes very easy. A calliper function allows measurement of such lesions.
A feature not advertised by Topcon, is its ability to view the anterior chamber in cross section. I have found this very useful for viewing narrow anterior chamber angles.
All captured images can be networked to any peripheral computer for viewing in other rooms. Images and reports are also easily exported for e mail or can be printed to share with colleagues.
The quality and array of OCT images produced by the Topcon 3D OCT, the ability to compare subsequent OCT images of exactly the area of retina and the fact that both OCT and fundal images could be captured with the one simple motion, ultimately led me to choosing this instrument. It does all it promises and I have been very happy the Topcon 3D OCT Mach 2.