https://www.vetsurgeon.org/f/clinical-questions/25306/why-is-this-dog-crashing-into-things I have a client with a yorkie about 5 yo. It walks around fine, no bumping into things and appears to see normally. PLRs are normal and I can&#39;t see anything obvious on it&#39;s retina. However on several occasions now when it has been running it has crasheden-USTelligent Community 10https://www.vetsurgeon.org/thread/172445?ContentTypeID=1Sun, 15 Jan 2017 17:19:51 GMT146601cc-3922-4be7-9974-7e1d4e45a66b:4777777f-0dd0-4c29-b91a-1664449e3bb6a.bardell<p>I&#39;ve got a 3 year old collie who we got as a rescue, not a natural working dog and could be described as nice but dim! Anyway he has done this- run into trees, tried to run through closed door etc so I got the ophthalmologist to check him out. Can&#39;t find anything wrong so suspect is just a bit lacking in the brain cell department <img src="/emoticons/v2/Very_happy_smiley.png" alt="Very happy" /></p><div style="clear:both;"></div>https://www.vetsurgeon.org/thread/172440?ContentTypeID=1Sun, 15 Jan 2017 14:33:43 GMT146601cc-3922-4be7-9974-7e1d4e45a66b:e39678eb-0cb8-4173-9bbc-030f9b29eab2grumpyoldman<p>You can look up the breed and tests available on Laboklin&#39;s web site. Most dogs have some degree of Hypermetropia. It could just be clumsy , maybe better to refer for retinoscopy, and OCT will find things pre, reflectivity changes and vascular attenuation.&nbsp;</p><div style="clear:both;"></div>