How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask DrRalston Your Own Question
DrRalston, Veterinarian
Category: Veterinary
Satisfied Customers: 2207
Experience:  Over twelve years of experience in surgery and internal medicine.
Type Your Veterinary Question Here...
DrRalston is online now
A new question is answered every 9 seconds

I have a mouse and one of its eyes is either swollen or

This answer was rated:

i have a mouse and one of its eyes is either swollen or bulging and slightly cloudy/milky. Other eye is fine and no change in appetite or behavior.
JA: I'm sorry to hear that. What is the mouse's name and age?
Customer: Mousie. Exact age is unknown. We adopted the mouse from my son's preschool a few months ago. I'm guessing the mouse is about a year old
JA: What is the mouse's name?
Customer: Mousie
JA: Is there anything else important you think the Veterinarian should know about Mousie?
Customer: no


Would you be able to post a photo of Mousie's sore eye?

I know that might be incredibly difficult considering the size of the pet and the squirming factor.

Customer: replied 1 month ago.
I can try later this evening, but I am at work right now.
Customer: replied 1 month ago.
Is there anything you think it might be without seeing a photo?

Ok, I understand no problem.

Let me ask just one or two quick questions.

It is just one eye, not both?

Customer: replied 1 month ago.
Just the mouse's right eye. Left eye isn't bulging or cloudy/milky. completely normal.

Ok, that is good. It is less likely to be a systemic illness if only one eye is affected.

Is there any discharge you have noted from the eye, other than watery? Any mucus, white or yellow for example?

And is the mouse sneezing at all or any discharge from the nose?

Customer: replied 1 month ago.
The tear duct area is moist, but as far as I can tell the discharge is not mucus, white or yellow in color. appears clear/watery. I have not noticed any sneezing and there's definitely no discharge from the nose.

What it sounds like it might be to me is a corneal ulcer. These can happen in mice very easily from handling issues, or from items within an enclosure with sharp edges. Even some substrates or bedding can poke the eye.

Sometimes you might be able to see a small puncture or hole. Other times not.

They might start to form tiny small red vessels in 5-7 days that come in and attempt to heal the eye.

It will look a little like that photo.

Customer: replied 1 month ago.
will these tiny red vessels actually heal the eye to the point where there is no vision loss? Is this an injury that requires time to heal or does it require medicated drops or some other treatment?

Sometimes these start as eye infections, especially herpes infections. But those are usually systematic diseases, and are accompanied by other signs, and typically affect both eyes.

A corneal ulcer may heal on it's own given time, and depending on how deep the ulcer or hole is.

Keeping the eye flushed of any debris or mucus if it builds up is important, but hard to do on mice. Artificial tears may be used to flush the eye of debris. A topical neosporin can also be used. Be advised it is NOT the ideal treatment at all, but can help cover that ulcer if present, and provide some relief to the pet.

You are right, medicated drops are usually the way to go, but you will have to get those from a Veterinarian.

And yes, the vessels can heal the eye to the point where there might be NO vision loss. That would depend on the depth of the injury again.

Usually though, there might be a smaller scar where the ulcer once was. It will look more like a white smudge on the cornea, like a dirty smudge on a bathroom mirror.

Larger areas of damage will lead to larger scars. The bigger the scar, the bigger chance of vision difficulty. That's more like looking through dirty glasses. The bigger the dirt spot, the harder to see.

Healing is usually about 7-10 days though. Think of it like a scraped knee. The cornea is skin too.

Customer: replied 1 month ago.
I just noticed this yesterday. Should I wait a couple days to see if it starts to heal or is this like an emergency where i need to try to see a vet?

Again, it's hard to say because I can't tell how severe the eye is right now.

I would say though, that if it is only cloudy, and it is very new, and you can still see the normal structure of the eye, especially if you can see the portion of the eye behind the damage, then it sounds less severe and might heal on it's own without a trip to the Vet.

Doesn't sound like an emergency just yet.

An experimental study demonstrated that twice weekly cage cleaning would reduce the incidence of corneal cloudiness to a very low level. A bacterial product, such as ammonia, is proposed as a significant factor in the pathogenesis of spontaneous corneal opacities in laboratory mice. It just builds up in the environment, and then irritates the eyes. So be sure to be cleaning out that cage really well too.

Customer: replied 1 month ago.
Gotcha. I've been cleaning cage once a week, including breaking down all components and washing with soap and water. I will clean again tonight and while he's out of his cage I will get a pic of his eyeball. Can I text or email you either later tonight or tomorrow and get some sort of final advice/recommendation? Not sure how this service works...

Occular pain though can be a MAJOR deciding factor in when to take the mouse into the Vet.

If the eye is squinty, it's painful. The degree of squinting may help you determine how bad that pain is.

In lab mice, there are topical pain meds that can be applied, and you can get these from your Vet too.

Sure, feel free to send those pictures tonight or tomorrow. I'll check back in to see if you have left anything new or have questions sometime in the next 24 hours or so? And if you have responded, I'll reply too.

And, if I think of any other helpful information, I'll post it here too.

Customer: replied 1 month ago.
OK. Do I just leave this webpage open? Will I continue to be charged. Or is the charge i've already received cover everything?

No, you just log back on you would e-mail or like a text window.

Our communications stay here where you can get back to them.

You don't need to leave this window open.

Eventually you will probably be asked to leave a rating and then you can feel free to reward or punish at will!

Customer: replied 1 month ago.
OK. Will send pic later.

Sounds good. Enjoy the rest of your day.

Customer: replied 1 month ago.
I have a couple of photos of the mouse's eye.

Hello there. Just checked back in myself. So, you should be able to attach those photos using that little paper clip above this chat window. Hopefully you have that. It's the last box next to a chain link, next to some dots.

You'll click on that, and then click choose file. That should open up your computer. On phones, I am not sure, but you should be able to kind of browse around to attach them.

OR you can definitely contact customer service for better advice on how to post those photos. I'm afraid that's more of an I.T. issue and less of an animal one. *smile*

How is Mousie doing?

Customer: replied 1 month ago.
Idk how to post photos. I clicked on the add files link and uploaded but I guess you don't see them?

Yep, I can see those just fine. Looks like a VERY small panda bear!

First, those are great pictures considering the patient.

I like a lot about this photo. The eye is open and not very squinty. That is a good sign it isn't very painful.

It looks like there is definitely some conjunctivitis in the lower eyelid on the right eye, in the corner closest to the ear. We call that the lateral canthus.

Could be Mousie is rubbing at it, or that there was an original damage or scratch to the lower eyelid that also damaged the cornea itself.

It looks to me like that is corneal edema, the whitish cloud that is hanging out in the cornea. And it doesn't look bad at all. That should resolve over time as soon as the corneal ulcer heals.

It will probably take about 2 weeks to heal due to the size. You will watch for those spidery small red vessels to creep up across the eye to the spot. That's ok. It's normal. But if the whole eye is blood shot, or looks like it is filled with blood, or you feel vision is gone to the eye and it is painful, then it might need to be removed.

I do NOT think that will happen. Not at all. Just letting you know though for information purposes ok?

Yep, and those eyes are big and buggy! Not uncommon at all for a mouse. So, Mousie will be prone to these kind of eye accidents.

Good luck!

BTW, you can still write to me. I think the rating thing I was talking about just popped up right?

DrRalston and other Veterinary Specialists are ready to help you
Customer: replied 1 month ago.
sir. I will rate you ⭐⭐⭐⭐⭐. So, to summarize, it looks like some abrasion damaged his eye, giving him swelling and a corneal ulcer. I should monitor and expect some healing over the course of the next few weeks. Doesn't seem too severe as to require a trip to the vet.
Customer: replied 1 month ago.
Also, just keep his cage clean with healthy food and clean water. He lives alone, so no other mice to worry about. Just tell the kids they can't handle him while his eye is healing.

Exactly! And it really is one of those things where it should look better from day to day, over the next several days.

You're doing great. Don't worry!

You should still be able to get back to this conversation at least for awhile if you wanted to update in the next couple of weeks. If all is well, and life is going as planned, and I don't hear from you, that's great too!

All the best,