Blog 15 April 2021

The original developer of the rebound tonometer

iCare HOME2 Tonometer

Since their launch in 2003, iCare’s patented tonometers that use unique rebound technology have grown to become the market leaders in handheld tonometry, thanks to a range of innovative features that give them a winning advantage over other tonometers in the market.

Before iCare’s patented rebound tonometer revolutionized the world of tonometry, traditional methods to measure intraocular pressure (IOP) posed quite a few challenges. The conventional applanation method requires anesthetics and a high level of expertise from the user. Non-contact tonometers often require the patient to remain still for a long period of time for an accurate measurement. In 2003, iCare introduced a pathbreaking tonometer that incorporated a unique rebound technology that resolved these issues. Today, iCare’s rebound tonometers are the market leaders in hand-held tonometry. The unique, quick, and easy technology for measuring intraocular pressure (IOP) has made them one of the most popular choices among eyecare health workers and patients worldwide.

Unique rebound technology makes measurement easy, quick, and accurate

The rebound technology’s working principle is based on measuring the movement of the probe during contact with the cornea. The key components are a lightweight, single-use probe, a driving coil, which moves the probe and a measuring coil, which measures the movement. The probe makes quick contact with the cornea and rebounds back. For high accuracy and to eliminate variation, the measurement is repeated six times. Once six successful measurements have been completed, the device analyses the measurements and displays the final result, together with the measurement quality indication.

The innovative rebound technology gives iCare’s tonometers a winning advantage over other handheld tonometers in the market. The key benefit is the ease of use. It is very simple, and anyone can take measurements within minutes of using the device. Measurement takes less than one minute to complete from start to finish. This makes iCare rebound technology the most user- and
patient-friendly method of measuring IOP.

iCare’s tonometers put safety and comfort of the patient first

Rebound technology in tonometry was developed by Dr Antti Kontiola, the then CEO and Product Development Director of Tiolat Oy (now Icare Finland Oy) in the mid-’90s. When he worked as a physician in a health center, he encountered a dementia patient who could not remain still for an IOP measurement. He also heard about a child patient who experienced long-term arrhythmia after anesthesia was used to measure IOP. That’s when he set out to create the first prototype of a rebound tonometer to address these problems.

Today, iCare is one of the most versatile tonometers since it requires no anesthetics – the measurement is fast and comfortable for the patient and very accurate. In addition, there is no applanation, which means the cornea is not harmed in any way. The patient doesn’t feel the measurement at all, so anesthetic drops are not needed. The gentle measurement technique also enables measurements soon after surgery. Other hand-held tonometers in the market either need anesthesia or fluorescein dye, use the air puff method which causes applanation, or are bulky and difficult to align correctly.

Patients contributing to glaucoma care with iCare technology

The gentle, easy and accurate rebound measurement technology has enabled iCare to develop the world’s first tonometer for patient use. The iCare HOME2 self-tonometer guides the patient to make the IOP measurement easily and accurately every time. Measurements by the patient at home enable the acquisition of diurnal, real-world IOP information. This helps the doctor in glaucoma management: from finding the optimal medication and instillation schedule to assessing the need for and effectiveness of surgery. Patient motivation for medication compliance can also improve.

Disposable probes provide added hygiene and safety

Another unique feature of iCare tonometers is that they use disposable probes, eliminating the risk of cross contamination between patients. iCare tonometers are extremely useful in the current Covid-19 situation. When used according to instructions, the tonometer is safe and does not spread micro aerosol particles as the air puff tonometers do, for example. In addition, the iCare measurement is so gentle and fast that it does not spread the eye’s tear film during the measurement.