Darkened Eye Orbit

The inside corner, or orbit, of one of my cats eyes has become darkened. Is this anything I need to be concerned with? He is a long-haired domestic around 5-6 years old. Below are some comparisons of his healthy right orbit and the darkened left orbit. Healthy Right Orbit: Darkened Left Orbit: Darkened Left Orbit (better lighting): Thank you for any help you can provide. Matt

Hello - I just want to check that we are seeing the same thing here as we are using slightly different terminology.  People refer to the bony outside rim of the eyesocket- and sometimes the surrounding skull bone - as the orbit.   In the picture, I think I can see some darker colouring to the fur, which looks darkest at the medial canthus, but I think you are telling me that it extends just below the lower eyelid as well or even right around the eye - is that correct?

If so, what appears to be happening is an increase in tears or discharge, from your description on the left side - is that correct?

I suspect that it would be caused by epiphora - a posh word for overflowing tears on that side.  The reasons can include a foreign body or increased exposure to dust on that side; something having scratched the eye's surface on the wetter side;  irritation caused by central heating, particularly if the patient sleeps with one particular eye against the bedding; infectious disease incliding respiratory viruses  (would usually affect both sides) blockage within the tear-duct (often inflammation) causing overflow; a inward growing eyelid (entropion); other eyelid abnormalities (extropion);  hairs from the face tickling the globe; allergy; changes to the pressure within the globe; unveitis and so on.  Eye changes can be emergencies and if not, can become so; it is generally reccommended that they are seen - or at least triaged - early.  There is nothing you have said that makes be panic, but eyes can change very fast, to the extent that many clinics have an 'if its an eye, treat as an emergency until proven otherwise' policy.  I hope that something there is useful.

I apologize, it appears that I have mis-used the term orbit. You are correct, it is the medial canthus area that I am referring to. I don't believe the area around the eyeball itself is much different from the other eye. So you believe that this is a discharge, would that mean that we are talking about some kind of infection? Any idea why it would be a darker color? Thanks.

I now see your further response. Thank you for the explanation!

For extropion please read 'ectropion,' the spell-check may have got over-excited there.  Regarding the eye, please have your vet triage it in order that you are seen in timing appropriate to the problem.  Wishing  you and your cat all the best - we'd love to hear how you get on.

Our replies keep missing each other - thank you for clarifying and best of luck!