The results of independent clinical assessment – prospective study of innovative non-invasive absolute intracranial pressure (ICP) value (mmHg) meter were recently published in the journal Neurology (The official journal of the American Academy of Neurology). This is the first prospective comparative clinical study of a non-invasive ICP measurement method that shows accuracy and precision which is acceptable for clinical practice.
All previous non-invasive ICP measurement approaches based on correlation between some measured parameter of some anatomical structure with that of ICP, faced the need of calibration to the individual patient and thus failed to show acceptable accuracy and precision during prospective clinical assessments because of impossibility of patient specific calibration.
The study conducted in Neurology Clinics of Lithuanian University of Health Sciences (Kaunas, Lithuania), with the support of the European Brain-IT Research Group and Southern General Hospital (Glasgow, UK) clinically assessed the non-invasive ICP measurement device based on a specially designed two-depth transcranial Doppler (TCD) technique for simultaneously measuring blood flow velocity in the intracranial and extracranial segments of the ophthalmic artery (OA) while increasingly applying external pressure to the orbit - the same measurement principle as used for non-invasive arterial blood pressure measurement . Non-invasive ABP measurement does not need calibration to the individual patient in the same way as proposed non-invasive ICP absolute value measurement technology.
The clinical assessment, which is a fact of evidence - based medicine, demonstrated the non-invasive ICP meter’s precision and accuracy comparing with “gold standard” invasive cerebrospinal fluid pressure measurement via lumbar puncture. Paired measurement data were obtained from randomly selected neurological patients with different diseases and covering a wide range of different physiological and anatomical variation. The results obtained show for the first time that proposed non-invasive ICP measurement technology provides accurate and precise ICP measurement without the need for patient specific calibration. This is a break through point in attempts to create non-invasive absolute ICP value meter with sufficient accuracy and precision for use in routine clinical care.
“We are standing on a new level of medicine. With this non-invasive intracranial pressure measurement technology clinicians will be able diagnose much wider spectrum of different neurological conditions and researchers will be able to refine in such aspects of disease, that earlier were absolutely impossible. E. g. now we are curing pain of migraine, but do we really know what is happening inside our heads at that moment of migraine attack and why the pain occurs?” says professor A. Ragauskas from Kaunas University of Technology – the inventor of innovative non-invasive ICP measurement technology.
Currently only invasive ICP monitoring technologies are available in brain trauma and neurological disease management requiring lumbar puncture or neurosurgical insertion of an ICP probe into the brain with the risk of inducing additional damage or infection to the brain tissue. In the traumatic brain injury (TBI) population ICP is monitored invasively in order to optimize the treatment of intracranial hypertension which is linked to clinical outcome. However, measurement of ICP invasively does carry some risks, such as an increased incidence of CSF infection which is associated with increased patient morbidity.
Furthermore, the invasiveness of current methods for ICP measurement limits the application of ICP monitoring in the diagnoses of many neurological conditions in which intracranial hypertension is a frequent and treatable adverse event. There are several neurological diseases where non-invasive assessment of intracranial pressure is clinically important but still impossible. Among these are stroke, idiopathic intracranial hypertension, neuroinfections and some neurodegenerative diseases.
Innovative non-invasive absolute ICP value measurement technology turns a complex invasive procedure applied to only the sickest patients in intensive care units into one that is safe, simple and quick – to - perform on neurological patients and patients with mild and minor brain injuries. The largest impact of the new method’s adoption in clinical practice will be on a large patient pool in which ICP measurements are currently avoided, but in which the availability of a clinically reliable ICP estimate would improve the timeliness and sensitivity and specificity of diagnosis and open up novel individual treatment options.
It is of substantial importance for healthcare professionals by improving the healthcare process and for the patients and their families by increased quality adjusted life years. We expect very wide application of the first non-invasive absolute ICP value measurement technology without the need of patient specific calibration in neurology, anesthesiology, transplantology, cardio surgery, sport medicine, aerospace medicine and combat casualty care.
 Ragauskas A, Matijosaitis V, Zakelis R, Petrikonis K, Rastenyte D, Piper I, Daubaris G. Clinical assessment of noninvasive intracranial pressure absolute value measurement method. Neurology. 2012 May 22;78(21):1684-91.