A word that puts fear into everybody’s heart… But, what is it?
Basically, it’s an increased pressure within the eyeball. There is a natural circulation of fluid within the eye and when the drainage area is blocked by whatever means, the pressure builds up causing pain and damages the light-sensitive cells at the back of the eye – the retina – causing blindness.
One of the first signs you might see would be if the eye looks sore and the white seems red. The eye can also look a bit blue/grey. It’s not unusual that your Dandie will shy away when you want to pat them on the head. The eye can remain painful and although there are treatments available that will bring the pressure down, unfortunately the condition is such that the eye may need to be removed if the treatment is not completely controlling the condition or the pain.
There has been a lot of work done, initially by the specialists in Finland and subsequently by the Animal Health Trust with James Oliver and Cathryn Mellersh (now the genetics unit at Cambridge vet school). The hope was that they could find a common pattern in the Dandie gene that was easily identifiable and that a genetic test could be produced such as with primary lens luxation in the Jack Russell terrier. However, many samples later, it became obvious that this wasn’t a straightforward situation… All Dandies (both pet and show) are advised to be tested by a veterinary ophthalmology. They will usually put in drops, then examine the eyes with an ophthalmoscope and a slit lamp (a bit like our own eye examinations). They will check pressures then put a special lens on the front of the eye called a gonioscopy lens and this will let them check the drainage angles, which are graded as below:
- 0 = Unaffected
– normal iridocorneal angle and unlikely to develop primary glaucoma
- 1 = 1–25 per cent of drainage angle affected
– still unlikely to develop primary glaucoma
- 2 = 26–75 per cent of angle affected, meaning moderately affected and low risk
– seek breed specific advice
- 3 = 75 per cent of drainage angle affected
– severely affected and highest risk of developing disease
Not all dogs with a grade 3 will develop glaucoma but at least if you know what the grade is the pressures can be monitored and any changes that are seen can be checked with a degree of urgency.
On questioning the experts re breeding from grade 2, the advice was to not breed early and to use a grade 0 who is not young either, as this is a later onset progressive disease. The hope is that careful pre-mating can monitor this.
Routine checks should be done every three years for Scottish Dandie owners living in the central belt. Edinburgh vet school now has a big contingent of very experienced ophthalmologists that assess eyes, and the BVA have a list of ophthalmologists that can carry out eye tests in the UK .
So, on discussion with the investigating professionals, they have put out a request to us all. If any Dandie is diagnosed with this problem, they would very much like to have a sample of their Dandie’s DNA. Sampling kits can be sent to either your vet to take a swab, or you can do it yourself if you are happy to do so and then send it to the genetics investigation team.
There are advances in gene investigation all the time and an answer will hopefully be on the horizon soon.
I can be contacted for kits by e-mailling to firstname.lastname@example.org