Author, Institution: Edgaras Misiulis, Lithuanian Energy Institute
Science area, field of science: Technological Sciences, Energetics and Power Engineering, T004
Scientific Supervisor: Dr. Algis Džiugys (Lithuanian Energy Institute, Technological Sciences, Energetics and Power Engineering, T 006).
Dissertation Defence Board of Energetics and Power Engineering Science Field:
Assoc. Prof. Dr. Habil. Algirdas Kaliatka (Lithuanian Energy Institute, Technological Sciences, Energetics and Power Engineering, T 006), chairman,
Dr. Amir Houshang Mahmoudi (Twente University, The Netherlands, Lithuanian Energy Institute, Technological Sciences, Energetics and Power Engineering, T 006),
Assoc. Prof. Dr. Algirdas Maknickas (Vilnius Gediminas Technical University, Technological Sciences, Mechanical Engineering T 009),
Prof. Dr. Arminas Ragauskas (Kaunas University of Technology, Technological Sciences, measurement Engineering, T 010),
Dr. Egidijus Urbonavičius (Lithuanian Energy Institute, Technological Sciences, Energetics and Power Engineering, T 006).
The doctoral dissertation is available at the library of Kaunas University of Technology (K. Donelaičio St. 20, Kaunas) and Lithuanian Energy Institute (Breslaujos g. 3, 44403 Kaunas, Lithuania).
In case of traumatic brain injury, intracranial and central nervous system tumor, infection after cranial surgery etc., where, if applicable, intracranial pressure monitoring is used to reduce health damage and maintain a high quality of life, and to increase the likelihood of survival in the most severe cases, it is important to increase the accuracy of the non-invasive intracranial measurement method, which is based on the peculiarities of the blood flow in the human ophthalmic artery. On this basis, the aim of this study was raised – determine dependencies of the blood flow of the patient-specific compliant ophthalmic artery on additional pressure applied during the non-invasive intracranial pressure measurement by using the numerical method.
To realize the research aim, a method for modeling the patient-specific artery using the state-of-the-art material model of the artery wall was developed, by forming a vector field that models the fibrous structure, which is characteristic to the arterial wall. In the study, the dependencies of the arterial blood flow on the intracranial pressure, measurement distance and the added external pressure, and also dependencies of the systematic deviation of the non-invasive intracranial pressure measurement on the prescribed intracranial pressure and measurement distance according to the differences of cross-sectional areas and average blood flow velocities were determined.
Determined ophthalmic artery blood flow dependencies provide preconditions for the increase of the non-invasive intracranial pressure measurement accuracy, and the resulting numerical model can be used to address problems where the interaction between compliant material and fluid flow needs to be considered.