It is about nine months since my colleagues and I based at the RNIB low vision centre in London took delivery of a Heidelberg Spectralis OCT (figure 1). Most of us were new to OCT use and, since then, we have developed our skills, improved the quality of data captured, and now routinely scan most patients. Over the coming months, we aim to share this experience and describe some of our successes as well as some of our initial mistakes. Though we have access to some patients with very severe, and sometimes rare, eye disease, we also have seen those without disease and very much want this series to be of value to readers of all levels of experience.
Over the coming months, each case book will focus on one of the following areas:
- Basic operation (figure 2) – the aim of these features will be to highlight some of the common errors made when first using an OCT (many of our initial scans were unusable simply due to a dirty lens), deciding on which of the often daunting choice of scans and displays to use, how to interpret data and how to monitor patients over time. Though we will obviously be using the Spectralis as our illustration, most of the information discussed should be common to most machines.
Figure 2a: What scans should I use?
Figure 2b: How should I save data? - Healthy patient assessment (figure 3) – we will look at a range of examples of healthy or anatomically variable discs and retinas and explain how these may be scanned and interpreted.
Figure 3a: Healthy retinas in a myope
Figure 3b: Asymmetric discs
Figure 3c: 3D image of a disc
Figure 3d: Highly myopic but non-glaucomatous disc - Diseased discs (figure 4) – a look at glaucomatous and abnormal discs, how best to assess them and to monitor them over time.
Figure 4a: Early retinal thinning indicative of possible glaucoma
Fgure 4b: Hemifield asymmetry
Figure 4c: late stage glaucomatous discs
Figure 4d: Advanced glaucoma - Macula assessment (figure 5) – the identification of the very first signs of RPE anomaly and macular degeneration through to advanced maculopathy.
Figure 5a: Early drusen
Figure 5b: Early maculopathy
Figure 5c: Progressing AMD
Figure 5d: Progressing AMD
Figure 5e: Advanced dry
Figure 5f: Wet AMD - Interesting cases (figure 6) – as the series progresses, we will look at some more unusual presentations of retinal disease we have come across.
Figure 6a: High myope with many floaters
Figure 6b: Advanced proliferative diabetic retinopathy
Knowledge Sharing
Once the series is established, we will be happy to publish cases sent in from readers and discuss their findings. We will also access the views of a panel of experts who may be able to offer advice to readers about any queries or concerns they may have about the operation of their OCTs in practice. Look out for details as to how you can participate in the series as the series begins.