Non-invasive
The only stimulus is room air at a controlled pressure.
In-office procedures · Diagnostic device
Corneal Esthesiometer Brill Measure corneal sensation without touching the cornea.
Brill's Corneal Esthesiometer is a portable, non-invasive instrument that tests corneal sensitivity using metered puffs of air. It is designed to help catch a loss of corneal sensation, support earlier treatment and track whether treatment is working.
5Stimulus steps
2.5 to 10 mbarAir pressure range
600 gWeight in the hand
10 yearsExpected service life
From air puff to a sensitivity reading
Air is delivered to the cornea at five set pressures. The patient says when they feel it, and the first level they notice is the measure of corneal sensitivity.
No contact
The instrument never touches the cornea, so patients with infectious corneal disease can still be tested.
Guided positioning
A built-in camera and two infrared LEDs meet at one point on the cornea when the distance is right.
Consistent between examiners
In a multicenter study of 91 subjects, differences within and between observers were not statistically significant.
Renedo Laguna et al. 2025Inside the Brill system
A compact hand-held unit that also mounts on the slit lamp.
- Five stimulus steps
- Hand-held or on the slit lamp
- Rechargeable, with a charging dock
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Two ways to hold it
Use it one-handed with your thumb on the controls, or fit it to a standard slit lamp.
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Rear display
Shows the live eye image, the chosen stimulus level and the pressure delivered, in millibars.
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Wired remote
Changes the stimulus level and triggers each air pulse.
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Calibration-free
The digitally compensated pressure sensor is calibrated at the factory, so there is no calibration or routine upkeep.
Running the test
No anesthetic is used. Begin at the lowest pressure and go up one step at a time until the patient feels the air.
Get ready
Have the patient sit upright, glasses off, blinking and breathing as usual. Lens wearers should leave lenses out for 24 hours or more. A puff on the back of the hand shows the patient what it feels like.
Line it up
Hold the unit upright or mount it on the slit lamp, then adjust the distance until the two LEDs meet as one point on the cornea.
Test
Begin at level 1 and fire once the shoot button glows steady green. Raise the level one step at a time until the patient feels the pulse.
Specifications and safety information
Technical specifications
| Model | 002 |
|---|---|
| Stimulus levels | 5 |
| Pressure range | Approximately 2.5 to 10 mbar |
| Display unit | Millibars (mbar) |
| Esthesiometer dimensions | 56 mm W x 203 mm H x 135 mm L |
| Esthesiometer weight | 600 g |
| Charging dock | 70 mm W x 114 mm H x 123 mm L, 560 g |
| Battery | 2 lithium-ion cells in series, 3.6 V each; replace approximately every 2 years |
| Operating conditions | 10 to 35 °C, 30% to 90% relative humidity |
| Equipment lifespan | 10 years |
| In the case | Esthesiometer, charging dock, power adaptor, remote control, instructions for use |
| Guarantee | 2 years from invoice date |
Indications for use
Corneal Esthesiometer Brill is a non-invasive device designed to assess the corneal sensitivity of the human eye by healthcare professionals (ophthalmologists and eye health staff) for aid in diagnosis of impairment of corneal sensation. It can detect an alteration in corneal sensitivity and help healthcare professionals determine whether current treatment is effective.
Contraindications
- There are no contraindications when used as intended by the manufacturer.
- In post-surgery scenarios, use is determined by the ophthalmologist.
- Use only on patients who can communicate whether they feel the air pulse.
Warnings and precautions
- For use by qualified healthcare personnel only.
- The esthesiometer must not come into contact with the patient's eyes.
- Use upright with the nozzle facing forward, never tilted upwards or downwards.
- Do not use anesthesia on the eye. It is not necessary for the examination and can alter the results.
- Do not use the device if it is wet or if ambient humidity is over 90%.
- Do not use near flammable substances.
- Interference is possible within 1 m of a device generating high-intensity electromagnetic emissions, such as a mobile phone.
Questions doctors ask about the Brill esthesiometer
What does corneal esthesiometry tell me?
How sensitive the cornea is to a stimulus. The corneal epithelium has more free nerve endings than any other tissue in the body, most of them supplied by the ophthalmic branch of the trigeminal nerve.
What can change corneal sensitivity?
Dry eye disease, contact lens wear, diabetic keratopathy, herpes simplex keratitis, neurotrophic keratopathy, keratoconus, Fuchs' endothelial corneal dystrophy, and procedures such as LASIK, LASEK and corneal cross-linking.
What happens to corneal sensation in dry eye?
Early on, nerve density and sensitivity can both rise. As the disease advances, nerve density can drop and the cornea can become less sensitive.
Is an anesthetic needed?
No. The exam does not need one, and an anesthetic can skew the result.
How does it relate to the Cochet-Bonnet esthesiometer?
Its pressure levels were modeled on Cochet-Bonnet values. A comparison study found good agreement and a similar range in healthy and dry eyes, though readings from the two are not interchangeable.
Can I buy it from Vision Rescue?
No. Brill Engines sells the esthesiometer directly and handles purchasing and training.
Clinical studies
Test corneal sensation with nothing touching the eye
A portable, non-contact esthesiometer with five stimulus steps that works in the hand or on the slit lamp.
Corneal Esthesiometer Brill is a trademark of Brill Engines. Read the complete manufacturer instructions for use, including every warning, precaution and contraindication, before use. Individual results vary.