I thought people might be interested in our recent experience. My Oliver, who has SM, has always been a bit light sensitive - in strong sunlight or under bright fluorescent lighting he starts squinting and is obviously uncomfortable. Once away from the strong light, he quickly recovers. A couple of weeks ago we spent the day at an obedience show (I have retired Oliver from working, but we still go to help). Although in the shade all day, he had a couple of short comfort walks in the strong sun during the day, and on the way home was definitely a pretty miserable dog. This time he took a day or two to recover - not helped by also getting a separate slight infection in one eye. I took him to the vet, who suggested I rang Oliver's neurologist at ChesterGates in case there was any connection with his SM. The neurologist ruled out a direct connection with his SM but said that the light sensitivity was due to the hydrocephalous caused by Chiari Malformation. Oliver's ventricles have quite sizeable dilation, which is obviously creating pressure at the back of the eyes, and this has been a longstanding symptom of his CM which simply wasn't recognised - just accepted as 'being a bit light sensitive'.
Really, dealing with CM/SM is like trying to fight the many-headed Hydra! You get one thing under control and something else appears. You eliminate one possible symptom - and another one presents. No wonder it's taking time to find causes, genes, better treatments etc - and thank goodness we've got people of the calibre of Clare Rusbridge, Geoff Skerritt, Nick Jeffrey and the rest working on it.
Kate, Oliver (now fine again) and Aled