Intracranial bypass for giant aneurysms treatment assessed by computational fluid dynamics (CFD) analysis.

Unruptured giant intracranial aneurysms (GIA) are those with diameters of 25 mm or greater. As aneurysm size is correlated with rupture risk, GIA natural history is poor. Parent artery occlusion or trapping plus bypass revascularization should be considered to encourage intra-aneurysmal thrombosis when other treatment options are contraindicated.

Computational fluid dynamics; a new diagnostic tool in giant intracerebral aneurysm treatment.

Giant intracerebral aneurysms (GIA) comprise up to 5 % of all intracranial aneurysms. The indirect surgical strategy, which leaves the GIA untouched but reverses the blood flow by performing a bypass in combination with proximal parent artery occlusion is a useful method to achieve spontaneous aneurysm occlusion. The goal of this study was to assess the utility of computational fluid dynamics (CFD) in preoperative GIA treatment planning.

Numerical flow experiment for assessing predictors for cerebrovascular accidents in patients with PHACES syndrome.

There is an increased risk of cerebrovascular accidents (CVA) in individuals with PHACES, yet the precise causes are not well understood. In this analysis, we aimed to examine the role of arteriopathy in PHACES syndrome as a potential contributor to CVA. We analyzed clinical and radiological data from 282 patients with suspected PHACES syndrome.

Inhaled drug airflow patterns and particles deposition in the paediatric respiratory tract.

Purpose: The effectiveness of inhaled drugs is strictly related to areas reachable by drug particles. Unless particles reach the desired part of the bronchial tree, their influence might not meet the expectations. Consequently, the disease progress might not be stopped or even slowed down.

A two-stage model of an arteriovenous fistula maturation process.

Purpose: An arteriovenous fistula has been a widely accepted vascular access for hemodialysis, however, a fistula maturation process is still not fully understood. In the short period of time, right after vein and artery shunting, the physical and biological changes take place mainly in the venous wall. A two-stage modeling method of arteriovenous fistula maturation process was proposed and presented.

Methods for determination of stagnation in pneumatic ventricular assist devices.

Background: A pneumatic paediatric ventricular assist device developed at the Foundation of Cardiac Surgery Development, Zabrze, equipped with valves based on J. Moll's design, with later modifications introduced at the Institute of Turbomachinery, Lodz University of Technology, was tested numerically and experimentally. The main aim of those investigations was to detect stagnation zones within the ventricular assist device and indicate advantages and limitations of both approaches.

Experimental investigations of the aerated polymethylmethacrylate-based vertebral cement flow in capillaries.

Introduction: A constant growth in the population suffering from osteoporotic vertebral weakening is observed. As a result, vertebroplasty procedures become more and more common. Unfortunately, they may be associated with several complications occurring during bone cement injection, including its leakage or overheating of tissues.

Particle image velocimetry tests on pediatric 45-cc and 30-cc ventricle assist devices: effects of heart rate on VAD operation.

Background: This study investigated flow analysis inside pediatric ventricle assist devices (VADs) designed and manufactured at the Foundation for Cardiac Surgery Development (FRK), Zabrze, Poland. The main goal of the experiment was to define the minimal heart rate admissible in clinical practice.

Methods: The flow was directed by mechanical, single-disc valves developed at the Lodz University of Technology, Institute of Turbomachinery in Lodz, Poland.

Numerical investigations of the unsteady blood flow in the end-to-side arteriovenous fistula for hemodialysis.

Purpose: The aim of this study was to investigate the blood flow in the end-to-side arteriovenous (a-v) fistula, taking into account its pulsating nature and the patient-specific geometry of blood vessels. Computational Fluid Dynamics (CFD) methods were used for this analysis.

Methods: DICOM images of the fistula, obtained from the angio-computed tomography, were a source of the data applied to develop a 3D geometrical model of the fistula.

Simulations of the blood flow in the arterio-venous fistula for haemodialysis.

The Ciminio-Brescia arterio-venous fistula is a preferred vascular access for haemodialysis, but it is often associated with the development of vascular complications, due to changes in hemodynamic conditions. Computational fluid dynamics methods were involved to carry out seven simulations of the blood flow through the fistula for the patient specific (geometrical) case and various boundary conditions. The geometrical data, obtained from the angio-computed tomography, were used to create a 3-dimensional CAD model of the fistula.

Numerical simulations of the blood flow in the patient-specific arterial cerebral circle region.

The Cerebral Circle Region, also known as the Circle of Willis (CoW), is a loop of arteries that form arterial connections between supply arteries to distribute blood throughout the cerebral mass. Among the population, only 25% to 50% have a complete system of arteries forming the CoW. 3D time-varying simulations for three different patient-specific artery anatomies of CoW were performed in order to gain a better insight into the phenomena existing in the cerebral blood flow.

Numerical simulations of the blood flow through vertebral arteries.

Vertebral arteries are two arteries whose structure and location in human body result in development of special flow conditions. For some of the arteries, one can observe a significant difference between flow rates in the left and the right arteries during ultrasonography diagnosis. Usually the reason of such a difference was connected with pathology of the artery in which a smaller flow rate was detected.