This year’s exhibition was notable for the rise in the angiography capability (the development of OCT algorithms that allow the analysis of reflected light from blood moving in vessels to visualise vascular patency without the need for fluorescein injections) in the higher specification OCTs along with the arrival of some new models, most familiar and one imported machine new to me altogether.
Topcon UK
Topcon offers a portfolio of OCT machines. There is the tried and trusted 3D OCT-2000 offering the full expected range of scanning functions along with high resolution retinal image capture, and an enhanced version of this offering fluorescein imaging and autofluorescence.
The 3D Maestro, with its easy operation making it a popular choice in community practice as auxiliary staff are able to take high quality images with minimal training, is still popular. I gravitated, however, towards the new DRI Triton (Figure 1).
[GalleryComponent="142"]
I have written about this (Optician 28.08.15) before but it is worth mentioning again a couple of points. Firstly, the machine is the first commercial unit to introduce swept source OCT to the market, the next step on from time domain and then spectral domain OCT.
This means that a longer incident wavelength is used and, as such, a very high resolution image is possible but with detail of the vitreous and the choroidal vasculature like never before (Figure 2).
The machine also offers a wide field scan and is able to show the whole anterior chamber in a single cross section (Figure 3). The penetration of the choroid makes it possible for the Triton to be adapted to run the new SS-Angio algorithm making assessment of vascular anomalies (like the neovascularisation in Figure 4) possible.
Heidelberg Engineering
Many look to Heidelberg for the latest in OCT advances, and indeed this year sees the introduction of its OCT2 software upgrade for the Spectralis (Figure 5). OCT2 increases the number of A-scans from 40,000 to 85,000 per second and this means much better resolution as can be seen in the detail of the optic nerve head and vitreous revealed in Figure 6. Active eye tracking also enhances the image, as can be seen by comparing Figure 7a, taken with standard OCT and Figure 7b with OCT2. OCT2 is also ready to incorporate the OCT angiography software once clinical trials are completed in the near future. Watch this space for launch details.
Haag Streit UK
Haag Streit is the distributor of the OptoVue range of instruments, the company to first introduce spectral domain OCT and OCT angiography to the market. Their iScan (Figure 8 shows me being scanned) is easily adapted to run a complete ‘well-being’ profile (Figure 9 is my report) and is a useful addition to any busy optometric clinic, especially when allied to other health professional health schemes. The AngioVue is, however, my choice of instrument (Figure 10) and, as we have mentioned in several previous articles, is able to easily show four en face views of retinal and subretinal tissues so allowing much greater assessment capability for a wide range of otherwise difficult-to-visualise lesions (Figure 11 shows the angiography view of a choroidal neoplasm).
Carleton Optical
Carleton showed off two OCT machines at Optrafair. The Canon OCT HS 100 boasts all the scanning options one would hope for in a spectral domain unit (look out for our review in the coming weeks). Also present was the new OCT from Optopol, the SOCT Copernicus REVO (Figure 12). With high resolution and also angiographic capabilities, this is a stride forward from the original trusted Copernicus we reviewed some years back and again I am looking forward to getting my hands on one soon.
Birmingham Optical Group
With the Retina Scan Duo OCT (Figure 13), Nidek has produced an excellent all-round machine that can be easily pre-programmed and used by staff with minimal training. It offers all the retinal and anterior scans one would hope for along with high resolution retinal digital imaging (Figure 14) making it a fine choice for community practice. There is now an interesting telemedicine functionality, which we will report on soon, and it is only a matter of time before we hear about angiography developments.
Zeiss
The Zeiss Cirrus is well known in optometric practices and hospital departments and the ease with which the software integrates data with other machines, such as field analysers, makes the system perfect for all-round structure and function assessment. The Cirrus 5000 HD is now able to offer AngioPlex OCT, the Zeiss version of angiography, and this makes vascular assessment within reach of the optometrist (Figure 15 shows choroidal neovascularisation). An interesting new machine is the Primus OCT (Figure 16) which is positioned on a slit lamp table and capable of the standard OCT scans – a useful instrument for those wanting the essentials of OCT capability.
BIB
Newly imported from China where it is currently the leading OCT model, the MOcean 3000 Plus OCT (Figure 17) offers good all round OCT options (Figure 18) in a cost-effective instrument. It includes patented ‘de-noising’ software that allows images to be presented with greater crispness and resolution and, again, I hope to be putting this through its paces in the coming months.
Optos
This company is known for its ultra wide-field imaging systems but has had an excellent spectral domain OCT – the OCT SLO – on its books for some time. I particularly like the fact that this is capable of integrated microperimetry and so able to match structural loss with functional changes.