Neurometer - scientific background applicability
Diabetes is one of the most significant public health problems worldwide, affecting the quality of life of hundreds of millions of people worldwide. In 2014, almost 422 million people were affected by some form of diabetes (WHO, 2016) and it was responsible for more than 1.5 million deaths.
Unfortunately, in our country, diabetes is a widespread disease. According to a 2019 survey, around 1.1 million adults and more than 500 children were living with diabetes (KSH, 2019).
Although diabetes is now considered to be a well-treatable disease, complications of the disease can lead to various impairments in the different organ systems. One of the most common of these complications is diabetic neuropathy, which covers the nerve damage caused by diabetes.
There are basically four types: peripheral, autonomic, proximal and focal neuropathy. Of these types, peripheral neuropathy affects more than 40% of patients with diabetes (Pfannkuche et al., 2020). Symptoms range widely from pain, numbness and numbness starting in the toes, toes, toes, and arms, to pain, numbness and numbness in the hands, to muscle weakness over time.
However, it can be said that these symptoms are mostly preceded by reduced sensitivity of the sensory nerves in the limbs. As a consequence, the patient often does not notice minor injuries or wounds, which can often become infected or even ulcerated due to the slower wound healing observed as a result of the high hyperglycaemia. Lower limb diseases such as infection, ulceration and tissue necrosis affect almost 6% of diabetic patients (Zhang et al, 2017), and around 1.5% of these patients undergo amputation (Lazzaini et al, 2015).
A comprehensive study in Hungary showed that amputations were performed fifteen times more often in people with diabetes than in people without
diabetes (Kolossváry et al, 2015; Kolossváry et al, 2016, Makai, 2021).
A significant proportion of these amputations could be prevented if limb loss were diagnosed early. Several methods are widely used to assess limb sensation itself. The simplest of these is the use of a calibrated tuning fork to assess the state of the sensory nerves. Another simple test is the so-called monofilament test, in which a special nylon filament is used to touch the area of the limb under test. Although these tests are simple to perform, they are less accurate and rather subjective. Another way of testing for peripheral neuropathy is to assess the indirect state of the nerves by examining the function of the sweat glands in the skin. Although this method is much more objective than the diagnostic procedures described above, it only gives an indirect picture of the state of the peripheral nerves. In contrast to these methods, the MDE Neurometer is a ready-to-use, electrodiagnostic test that can assess the state of the sensory nerves and provide an objective CPT (Current Perception Treshold) value.
The Neurometer, unlike the devices previously described, allows separate testing of type C (small unmyelinated), type Aδ (medium myelinated) and type Aβ (large myelinated) sensory nerve fibres. Each nerve fibre type can be stimulated frequency-specifically with different mA current ranges. Thus, based on the patient's feedback, the device determines the CPT value that is not yet associated with pain sensation on the nerve fibre.
Perfusional neuropathy is often a concomitant symptom of other diseases, for which the Neurometer can also be a useful diagnostic tool to assess the status of peripheral nerve pathways and monitor possible changes. Damage to sensory nerve fibres type C has been observed in several chronic inflammatory diseases, such as chronic renal failure (Arnold et al., 2016), and peripheral neuropathy is a common accompanying symptom of neurodegenerative diseases. The peripheral nerve pathways of patients with Alzheimer's disease are also frequently damaged by lesions caused by amyloid oligomers (Fukumoto et al., 2010). In addition to chronic diseases, more than 36% of patients infected by the COVID-19 virus, which has caused the greatest public health crisis in recent times, have neurological symptoms, with sub-acute peripheral neuropathy being very common. Thus, the Neurometer may be a useful tool to assess the neurological status of patients with post-COVID syndrome.
The use of the device itself is simple and after a short training it can be easily integrated into routine examinations. The device requires no maintenance or recalibration, as all systems come factory calibrated, with minimal need for servicing.
The test parameters are set and controlled, and patient data is recorded via a computer and tablet connected to the device. The results of all the tests performed on a given patient can be retrieved retrospectively, making the device a great help in monitoring the patient's condition and assessing the effectiveness of the therapy used.
