Glaucoma are eye diseases that damage the optic nerve and can cause the optic nerve to die in the long term. In our eyes there is a constant exchange of aqueous humor – new is produced and old is disposed. However, if the amount of newly produced aqueous humor is larger than that of the draining liquid, the intraocular pressure increases and so does the risk of damage to the eye.
At the beginning, the disease is genally not noticable for patients – the disease is often only noticed when many optic nerves have already died and the visual field is reduced – in many cases, patients have already lost more than one third of their vision before the damage to the optic nerve is noticed.
To prevent the spread of glaucoma, the intraocular pressure must be returned to the normal range and maintained there. For the treatment, drugs are available in form of eye drops. In the case of a more advanced disease, surgical intervention is used. The right therapy must be chosen during treatment. This requires the doctor to know how high the pressure in the eye is and what time course it takes.
However, the measurement methods provide only a small data basis and therefore no reliable information. As a rule, measurements are carried out in the doctor's office and there are therefore long intervals between examinations. In addition, there is a high probability that harmful high values, which can occur several times in the course of a day, will not be detected. The risk of making the wrong therapy decision is increased many times over.
Eyemate for Non-Contact Pressure Measurement
There is an easier way: The Fraunhofer Institute for Microelectronic Circuits and Systems IMS in Duisburg (IMS) and Implandata Ophthalmic Products (IOP) together developed Eyemate – a microsensor system with which the patients can perform non-contact pressure measurement in the eye themselves. A sensor implanted in the eye measures the pressure and temperature. The values are recorded, digitized, and passed on with a hand-held reader that the patient simply holds in front of his eye.
Pressure and temperature in the eye can be measured precisely at any time – within seconds. This provides doctors with a high database for creating the right therapy. The measurement results can be transferred to a cloud memory. This allows the attending physician to access patient data at any time to check the course of the disease and, if necessary, to adjust the therapy directly – without the patient having to come to the practice.
With an app for the smartphone, patients can also access their data directly and follow the course of intraocular pressure and react if the pressure is too high. The more frequently the patient uses the reader, the more meaningful the measured values are and the more individually the therapy can be coordinated.
Sensor System with CE Approval
The intraocular pressure sensor was developed by the Fraunhofer IMS in Duisburg as a semiconductor circuit. It is a passive microsensor activated by the reader. In a clinical study at several hospitals in Germany, the intraocular pressure sensor was successfully validated. In addition, Implandata received CE approval for the sensor system in mid-2017.
According to the Fraunhofer IMS, the study has shown that the reduced barrier increases the motivation of patients to take regular measurements, but that in particular the therapy can be personalizedand the necessary therapy adjustments can be made by the ophthalmologist at an early stage. In addition, irreversible loss of vision can be avoided.