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smanimalvet, Veterinarian
Category: Dog Veterinary
Satisfied Customers: 1111
Experience:  Practicing vet with focus on advanced medicine and surgery.
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my dogs one eye is extreemly dilated, while the other is not,

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my dogs one eye is extreemly dilated, while the other is not, they both contract an equal amout from light, but this just brings one to normal and the other to a pin prick, ths has happened before but has gone away, now that it has come back I'm concerned, she is also unusally hyper, that may be unrelated as she is a 4 mo old puppy, but never the less I felt I should mention it

Hi Twiztid-


My name isXXXXX and I hope to help you out a little bit. This is a difficult question to answer as it requires one vital piece of information that really can only be confirmed by seeign the dog and that is, which eye is normal? Is the one realy dilated (called mydriasis) or is the other really constricted (miotic).


There are a number of conditions that can cause both. If one is constricted completely, a lot of times this may be due to trauma of the eye though there are a number of different causes. Can you answer the folowing for me?


1. Is either eye really red or irritated?

2. Does she act painful in or around the eyes?

3. Does either eye have any discharge?

4. Does she appear to be able to see out of both eyes?

5. Does she shy away from light?


With these questions I can help you a little more. I will say this though, I personally don't mess around with eyes too much. Even though it may be nothing serious, vision can be lost in a very short period of time.


I hope this helps and I look forward to your response!

Customer: replied 7 years ago.
no neither eye is red nor do they appear to be painful, her right eye is dilated, while the left is constricted, neither is really the norm, she has no problem with light, and seems to be able to see fine, currently (I just took her out and it is night here) they are back to normal, previousl neither were normal, the constricted one was close at its most dilated, but the dilated one was closer at its most constricted, but once again they have now returned to normal, I should also note that her left pupil reflects red in the light, it has always done so but I have never thought of it as an issue

Excellent...thanks for being so prompt on your reply. It sounds like you may dealing with a little ciliary spasm potentially though without examining I cannot be sure. The ciliary muscles are what causes the eyes to dilate or constrict. A lot of times this is related to trauma to the eye and resolves over the course of 24-48 hours. WIthout examining I cannot be certain of course.


It is promising that there are no other related ocular signs that you are seeing. I would continue to monitor for any of the following signs or symptoms: redness, irritation, excessive blinking, rubbing the eye, yelping, lethargy, inability to remain balanced. If this continues you have to be concerned about some sort of congenital eye problem that should be seen by your local veterinarian.


I hope this helps...let me know if it doesn't!



Dr. Bone

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