How do you clean Icare tonometer probes for personal reuse?
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11 hours ago

There is a similar question here: How do you manage probes for the Icare tonometer for personal use?

However, that question focuses on whether or not personal Icare users can reuse probes and generally how that process is managed. My current question is specifically about the best way to clean the probes, having already decided I will reuse my probes (on myself only, of course).

I would like to know the detailed recommendations for cleaning Icare probes (and probe tubes) please.

tonometer-maintenance icare self-tonometry • 100 views
Entering edit mode
11 hours ago
david 2.5k

Simple answer: gently swish the probes in isopropyl alcohol and dry with canned compressed air. Periodically clean the probe tube/probe base too, using the same supplies. More details follow:


Most of us use isopropyl alcohol and canned compressed air for cleaning the Icare parts (probes and probe tube). You may also need a small glass bowl or other container.

I use a can of compressed air that you can purchase from a camera or electronics shop (or even an office supply store). It generally comes with a plastic tube that optionally attaches to the nozzle. (That tube is important if you use my drying method below.) Alternatively, a cordless air duster might work.

The purpose of the compressed air is to both achieve better cleaning results and to dry the parts to prevent corrosion from happening.

I have used both 70% isopropyl alcohol (available at any corner drug store) and 97% (not as easy to find in USA). I have not found a higher concentration in the USA, but in other countries FitEyes member have stated that they use better than 99% pure isopropyl alcohol.

The less pure isopropyl alcohol varieties contain water. This can cause probes to rust if you leave them in the isopropyl alcohol for an extended period of time, or you don't dry them (e.g., with compressed air). However, in my experience, if 70% isopropyl alcohol is all you can find, it will work well. Just make sure you blow dry the part with compressed air.

I did try hydrogen peroxide once for cleaning probes and it ruined them -- it caused corrosion.

Cleaning Procedures


  • probe container: the plastic tube with cap that new probes are sold in. (I won't call it a tube to avoid confusion with the probe tube. I will just call it the "container.")
  • probe: the disposable item that freely slides in and out of the Icare tonometer and is used to make the measurement
  • probe tube: the component inside the tonometer that the probe moves inside. It's a metal shaft or tube. It comes out of the tonometer only when you remove the cover. See the Icare manual.

Cleaning probes

I generally clean more than one probe at a time.

Put the probe(s) into a small glass bowl with some isopropyl alcohol. Swish them around gently. (Don't leave them in the isopropyl alcohol for hours. A few minutes is sufficient, I think.)

Dry the probes. I guess you could lay the probes out on a paper towel and gently blow them dry with compressed air, being careful not to blow them away.

However, one method I have come up with is drying them inside the probe containers. I slide the probe, still wet from the isopropyl alcohol, into the container, head first. Then I point the long air tube of the canned compressed air into the container (usually encompassing the end of the probe shaft) and blow dry everything. If you don't put the air tube into the plastic container, you will blow the probe out and probably damage it or even lose it. If you use this method, the air tube must go into the end of the container when you blow.

Cleaning probe tubes

Here's how I clean my probe tubes:

  1. swish the probe tube in isopropyl alcohol
  2. use compressed air to blow dry the inside (and outside) of the tube

You should use cleaned (or new) probes after you clean the probe tube. Don't use dirty probes in your newly cleaned probe tube.

Cleaning the Icare probe tube is critical to proper operation and it needs to be cleaned frequently. A slightly dirty probe tube affects the accuracy of the Icare tonometer. Cleaning it once a week is probably ideal, but if you see any decrease in your ability to obtain acceptable measurements, clean the probe tube.

Some FitEyes members have suggested cleaning the inside of the probe tube with a small nylon brush might be much better than just using alcohol and compressed air, as mentioned above. If you want to try that, you could use these steps:

  1. swish the probe tube in isopropyl alcohol
  2. brush the inside of the tube while it is wetted with alcohol
  3. use compressed air to blow dry the inside of the tube

Here are some of the nylon brush types I have looked at:

  • 5 pc. Mini Nylon Brush Set
  • Tattoo Tip and Tube Cleaning Brush 6 Pc Set
  • Nylon Brush Set for Cleaning Airbrushes, Spray Guns
  • Hummingbird Feeder Bushes
Entering edit mode

Do you have a link to buy sterile compressed air online? I've searched and have not found anything

Entering edit mode

I picked mine up in a local office supply store, but I bought enough to last several years. I just learned that there is a policy now dictating that this type of product must contain a bitterant to discourage inhalant abuse. I do not see the sterile compressed air available online. Maybe one of the cordless air dusters that are getting popular would be a better alternative.


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