I suspect a high percentage of those who consult you about diminishing sight are among the 1 million people in the UK who live in a world of vivid, silent, visual hallucinations. However, unless prompted, very few will confide about the images which disturb or frighten their daily lives, for fear that they are caused by a mental health condition. It is up to the optometrist to ask the question or warn a patient whose sight is at risk.
As I am sure you know, CBS occurs when a patient has lost over 60% of sight, at which point the messages from the retina to the visual cortex slow or stop – but the brain does not. It fires up and creates its own images. What is seen depends on which part of the brain is firing at that moment.
The UK leads the world in research, the funding for most of which has been sourced by Esme’s Umbrella. Dr Dominic Ffytche at King’s College London is the sole, globally-acknowledged expert and first researcher in CBS and his work has dispelled many myths. We know now that CBS occurs following loss of sight from any of the eye diseases (not just macular degeneration), or from cancer, accident, stroke, diabetes or another condition which damages the optic nerve; that it is not just a condition of the elderly – children are just as likely to develop the condition; and that it does not disappear after 18 months.
Not everyone dislikes what they see, but the frequency of the CBS episodes negatively affects quality of life. Two quotes stay in my mind – one from someone who said to me ‘It is like a gardening documentary – but I can’t switch it off’ and another who said ‘It is like watching a horror movie that I would never have chosen to watch – and I cannot switch it off’.
Not being able to differentiate between what is real and what is not causes people to become housebound and falling over, whilst avoiding the sudden appearance of a tiger, flames or gushing water is common. For some people, the nature of what they see is so disturbing that suicidal thoughts are harboured.
The loneliness felt by people living with CBS is about being isolated in a world of uninvited images. Imagine how more isolated someone would be who had not received a warning. Forewarned is forearmed and it has been proved that the outcome is much better when the patient can recognise the first hallucination for what it is and not think – wrongly – that it heralds a mental health condition.
At the same time as warning patients, it is useful to explain that isolation, stress and fever exacerbate the episodes of CBS and this was confirmed by the experiences of patients during lock-down. Worryingly, we also had reports that the images seen were much more frightening.
It is also worth checking the medication being taken by the patient – including eye drops – because one of the side effects (not always included on the packet) can be hallucinations. Changing to an alternative brand might help. Otherwise, the patient experiences a ‘double whammy’ of images.
Far too few GPs and hospital doctors are aware of CBS, so should your patients be referred, please send the information from Esme’s Umbrella with them, so that there is not an unnecessary ushering down the mental health route.
Now that Esme’s Umbrella has persuaded the WHO to give a coding to CBS in ICD 11, the next step is to ensure that CBS is included in specialist ophthalmology services through NHS commissioning. As optometrists are now the ‘GPs for Eyes’, I would be hugely grateful for your help.
I launched Esme’s Umbrella at the House of Commons in 2015 in memory of my mother, for whom CBS destroyed any quality of life she had in her final years. Her optometrist had never heard of CBS, but that was in 2009 and I know the situation is very different now. The fact that over 500 people chose to attend this year’s CBS Patient Information event online shows that, at last, the CBS community’s voice is no longer a whisper. Thanks are due to the many optometrists who have given me and my campaign so much support. With your help, this perplexing condition has come out of the shadows.
Further information
W: www.charlesbonnetsyndrome.uk
E: esmesumbrella@gmail.com
T: 020 7391 3299 (the helpline is answered for Esme’s Umbrella by the Eye Health Team at the RNIB)