How can I increase the cornea temperature?

[bakunin]

Most days of this year the AC in my workplace was off. Specially in the last months

I wear moisture chamber glasses at work. But even wearing them the AC makes a huge difference. From now on the AC will be working almost everyday here . That means the torture is starting again

I never had damages or erosions in my cornea. My probem is my symptoms: pain, or burning feeling to be more exact.
Well, I've learned that one of my problems is a 'evaporative corneal hyperalgesia' (see the article The Corneal Pain System by Dr. Perry Rosenthal). When my corneas are in a relative high temperature my pain is gone, or at least I have much less pain. Warm compresses, sun in my face and vapor (from tea for example) in my eyes gives me imediate relief.

The question is: how can I keep my corneas warm? Do you know any eyedrop or something else that doesn't 'refresh' the eyes, but, instead, makes the cornea warmer? (Maybe that is one of the reasons all eyedrops make me worse: they are cold.)

Any ideas will be very helpful.

thanks.

[No tears in ATL]

Would increasing body temperature in general help? It could just be placebo, but I feel generally warmer the rest of the day if I exercise vigorously in morning. And somehow, that makes my eyes feel slightly better. Do you get out during lunch? Maybe take a brisk walk then as well.

I am with you on the A/C--though most here would love to come down South where we have a warm, steamy climate, folks just loooooove to crank up that A/C in every building here. 65 degrees is NOT a good working temperature for an office.

[zuzu70]

I never had damages or erosions in my cornea. My probem is my symptoms: pain, or burning feeling to be more exact.
Well, I've learned that one of my problems is a 'evaporative corneal hyperalgesia' (see the article The Corneal Pain System by Dr. Perry Rosenthal). When my corneas are in a relative high temperature my pain is gone, or at least I have much less pain. Warm compresses, sun in my face and vapor (from tea for example) in my eyes gives me imediate relief.

The question is: how can I keep my corneas warm? Do you know any eyedrop or something else that doesn't 'refresh' the eyes, but, instead, makes the cornea warmer? (Maybe that is one of the reasons all eyedrops make me worse: they are cold.)

That is a very interesting observation about corneal temperature. I have noticed the same thing with my eye...the eye feels great when it's warm. Even something like sitting very near a campfire, which you'd think would totally dry out my eye, feels great. I don't have any magic temperature-raising method, but I do tend to keep my artificial tears in my pants pocket and that way they're warm when I apply them. (One note on this...I tend to put more tears in this way because they're body temperature and I can't feel when they first hit my eye, only when they start to run over.) I'm very interested in reading the article you mentioned, because I thought I was the only one that felt that about eye warmth and I thought I was crazy.

[bakunin]

Hi zuzu70,

I don't use artificial tears, but I thought about trying them again the way you said: keeping them on my pants pocket.
You can download the article here: http://www.dryeyezone.com/talk/showt...y-Dr-Rosenthal

[patrick]

I can completely relate to this.
When i am in a warm/hot environment my eyepain immediately disappears!?
Which i think is contradictory,because you'd think an increase of temperature accelerates evaporation.
For instance i do not have eyepain when i am; near an open fire, do some cooking above a hot stove,i am doing some welding on my car and when i drive a really hot car (without ac of course) with the windows closed.
Until now i always thought that the decrease in pain could be caused by the liquification (did i spell that right? guess not) of the lipids in the meibomian glands due to the raised temperature.
It now turns out that this clearly is not the case.
Anyone here who can explain a bit how this decreased pain level can occur in relation to a higher temperature?

Thanks!
Patrick..

[bakunin]

I can completely relate to this.
When i am in a warm/hot environment my eyepain immediately disappears!?
Which i think is contradictory,because you'd think an increase of temperature accelerates evaporation.
For instance i do not have eyepain when i am; near an open fire, do some cooking above a hot stove,i am doing some welding on my car and when i drive a really hot car (without ac of course) with the windows closed.
Until now i always thought that the decrease in pain could be caused by the liquification (did i spell that right? guess not) of the lipids in the meibomian glands due to the raised temperature.
It now turns out that this clearly is not the case.
Anyone here who can explain a bit how this decreased pain level can occur in relation to a higher temperature?

Thanks!
Patrick..

Yes, patrick.

In the article I linked above Perry Rosenthal explains why.

15% of the cornea nerves have thermosreceptors. In normal people they are triggered by the lowering temperature due to tear evaporation, sending pain signals (a way to say: hey, you need to blink or close your eyes).
Rosenthal calls evaporative corneal hyperalgesia when they are more sensitive than usual (due to inflammation for example).

Quoting the authors:

How Does the Cornea Monitor Tear Evaporation?
Maintaining the integrity of the optical tear layer during waking hours is a constant battle with evaporation. In this context, it can be argued that tear evaporation is the cornea’s foremost noxious threat. In order to maintain stable, acute vision, it is necessary for the cornea to signal the need for more tears just prior to degradation of the optical tear layer. How does the cornea sense the optimal timing for this pre-emptive action? The most plausible mechanism involves a recently identified class of cold corneal thermoreceptors (TRMP8) that are exquisitely sensitive to dynamic downward shifts in temperature
(...)
When working in harmony, the activation thresholds of corneal receptors are putatively set to levels appropriate for maintaining the integrity of the tear layer over a range of evaporative environments without triggering conscious symptoms or excessive blinking. Nevertheless, their sensitivity is not static. Inflammatory mediators released from damaged tissue and recruited immune cells increase the expression and lower the activation thresholds of nociceptive transducers. The resulting increased sensitivity and responsiveness to noxious stimuli define the state of hyperalgesia. Hypersensitivity to tear evaporation (corneal evaporative hyperalgesia) is the most common type of corneal hyperalgesia, as identified by the suppression of these symptoms when tear evaporation is blocked by a scleral lens (personal observations).
(...)
These findings suggest that the products of ongoing nociceptor activity can themselves lower the activation thresholds of the corneal receptors, thereby creating a positive feedback loop that results in the state of corneal hyperalgesia including hypersensitivity to tear evaporation.
(...)
Otherwise unexplained dry eye-like symptoms are assumed to be due to accelerated tear evaporation caused by MGD. However, it has been reported that 21% of patients whose dry eye symptoms are not reflected by external signs do not have MGD, whereas many patients with significant MGD are asymptomatic. These findings suggest that the link between MGD and chronic corneal symptoms is more complex than hitherto believed and may be governed by other factors– in particular, the sensitivity of responsive corneal nociceptors.
(...)
The observation that small incremental lowering of corneal temperature evokes sensations of discomfort in human subjects supports the notion that increased sensitivity of the cold receptors can account for symptoms of ECH.

The bad news: there is no 'official' treatment for that. Scleral lenses or thickening the tear layer (drops and plugs) are recomended. But I would like to think about a way to keep the corneas warm, or treating the inflammation, or rising the body temperature.

[patrick]

Thanks!
That's a thorough explanation.
Just read it for the first time,but i have to admit that it will take me at least two or more times reading before i fully understand the whole drift of this explanation. The text is clear enough,but my english is not all that i'm afraid.

I will react more detailed when i fully understand everything you wrote

Besides plugging the tearducts and using eyedrops could a nsaid based eyedrop be helpful to get some pain relief?

Patrick..

[bakunin]

Thanks!
That's a thorough explanation.
Just read it for the first time,but i have to admit that it will take me at least two or more times reading before i fully understand the whole drift of this explanation. The text is clear enough,but my english is not all that i'm afraid.

I will react more detailed when i fully understand everything you wrote

Besides plugging the tearducts and using eyedrops could a nsaid based eyedrop be helpful to get some pain relief?

Patrick..

I don't patrick. But I used one, prescribed by a doctor, twice a day for 5 days and I felt no difference (well I felt no difference with restasis and artificial tears either).

I think it is easier to understand reading the article than reading those quotes. I had to read carefully to get the point either. But it was the explanation I needed to understand what is happening in my eyes. It fits with my symptoms and the relief I feel in a hot or warm environment.

[avee]

Same here - during hot days the oils are flowing and my eyes are lubricated without any drops, no inflammation. As soon as the weather turns normal they become red and dry and develop inflammation.