Viktor Till

Current diagnostic trends in radiology

Since the discovery of X-rays by Wilhelm Conrad Röentgen at the end of the 19th century, diagnostic imaging techniques have been continously improved by technological advances, bringing radiological diagnosis into the very center of modern medicine. Nowadays, it is hard to imagine therapy planning without previous radiological examination. Great advances in the field of computer technology have been accompanied by development of radiological techniques, and today they include not only morphological and anatomical, but also dynamic, functional and molecular imaging. This paper is an overview of new and improved radiological techniques and their implementation.

Dynamic magnetic resonance imaging of the cerebrospinal fluid flow within the cerebral aqueduct by different FISIP 2D sequences

Background/Aim. A vast majority of current radiogical techniques, such as computerized tomography (CT) and magnetic resonance imaging (MRI) have great potential of visualization and delineation of cerebrospinal fluid spaces morphology within cerebral aqueduct. The aim of this study was to determine the possibilities of two differently acquired FISP (Fast Imaging with Steady State Precession) 2D MR sequences in the estimation of the pulsatile cerebrospinal fluid (CSF) flow intensity through the normal cerebral aqueduct. Methods. Sixty eight volunteers underwent brain MRI on 1.5T MR imager with additionally performed ECG retrospectively gated FISP 2D sequences (first one, as the part of the standard software package, with following technical parameters: TR 40, TE 12, FA 17, Matrix: 192 × 256, Acq 1, and the second one, experimentally developed by our investigation team: TR 30, TE 12, FA 70, Matrix: 192 × 256, Acq 1) respectively at two fixed slice positions - midsagittal and perpendicular to cerebral aqueduct, displayed and evaluated by multiplegated images in a closed-loop cinematographic (CINE) format. Results. Normal brain morphology with preserved patency of the cerebral aqueduct in all of 68 healthy volunteers was demonstrated on MRI examination. Cerebrospinal fluid flow within the cerebral aqueduct was distinguishable on both CINE MRI studies in midsagittal plane, but the estimation of intraaqueductal CSF flow in perpendicular plane was possible on CINE MRI studies acquired with experimentally improved FISP 2D (TR 30, FA 70) sequence only. Conclusion. Due to the changes of technical parameters CINE MRI study acquired with FISP 2D (TR 30, FA 70) in perpendicular plane demonstrated significantly higher capability in the estimation of the CSF pulsation intensity within the cerebral aqueduct. .

Duplex doppler ultrasonography in the diagnosis of deep venous thrombosis of the lower extremities

INTRODUCTION The aim of this study was to investigate the role of duplex Doppler ultrasonography in diagnosis of deep venous thrombosis (DVT) of the lower extremities. MATERIAL AND METHODS During a 2-year period, 860 patients were examined by duplex Doppler sonography. Among these, 619 (72%) were women and 241 (28%) men, with the age-range of 16-91; (mean 56,2) years. Siemens Versa Pro colour doppler was used, with 7MHz transducers. Findings were categorized into four categories: 1. deep venous thrombosis (DVT); 2. pathology predominantly related to superficial veins without DVT; 3. pathology of superficial and deep veins; 4. normal findings. RESULTS 185 (21%) patients had DVT, 366 (42.5%) patients had predominant pathology of superficial veins: postthrombotic syndrome, superficial thrombophlebitis and varicose veins. 128 (14.9%) patients had pathology of superficial and deep veins. Normal findings were found in 181 (21.1%) patients. COCNCLUSIONS: Various vascular and nonvascular diseases may mimic deep venous thrombosis, and that is why US should be used whenever possible to avoid unnecessary anticoagulant therapy.

Dynamic simulation and Doppler Ultrasonography validation of blood flow behavior in Abdominal Aortic Aneurysm

Criteria for rupture prediction of Abdominal Aortic Aneurysm (AAA) are based only on the diameter of AAA. This method does not consider complex hemodynamic forces exerted on AAA wall. The methodology used in our study combines Computer-Aided Design (CAD) with Computational Fluid Dynamics (CFD). Three-dimensional vascular structures reconstructions were based on Computed Tomography (CT) images and CAD. CFD theory was used for mathematical modeling and simulations. In this way, dynamic behavior of blood flow in bounded three-dimensional space was described. Doppler Ultrasonography (US) was used for model results validation. All simulations were based on medical investigation of 4 patients (male older than 65years) with diagnosed AAA. Good correspondence between computed velocities in AAA and measured values with Doppler US (Patient 1 0.60m·s-1 versus 0.61m·s-1, Patient 2 0.80m·s-1 versus 0.80m·s-1, Patient 3 0.75m·s-1 versus 0.78m·s-1, Patient 4 0.50m·s-1 versus 0.49m·s-1) was noticed. The good agreement between measured and simulated velocities validates our methodology and the other data available from simulations (eg. von Misses stress) could be used to provide useful information about the possibility of AAA rupture.

Lower back pain - silent symptom of chronic infrarenal abdominal aneurysm rupture

INTRODUCTION The rupture of infrarenal abdominal aortic aneurysm is a surgical emergency condition with a high rate of mortality before the patients arrive at hospital. The signs and symptoms of abdominal aortic aneurysm rupture into the retroperitoneal cavity are pulsatile mass, abdominal pain, hypotension and shock, but sometimes silent symptoms also hide a dangerous and life threatening condition, such as chronic aneurysm rupture of abdominal aorta into the retroperitoneal cavity. CASE REPORT We present a patient having had the lower back pain for 4 months, which had been recognized and treated as lumbar ischialgia but which was eventually diagnosed to be chronic infrarenal abdominal aortic aneurysm rupture by computed tomography angiography. The surgical intervention was successful and the patient was discharged from hospital after 6 days without any clinical complications. Preoperative imaging by computed tomography angiography of ruptured abdominal aortic aneurysm is highly sensitive for detection of several specific signs for rupture. This condition leads to urgent vascular surgery.

Stent graft infixation after venous dislodgement in a patient with femoral posttraumatic arteriovenous fistula.

INTRODUCTION An arteriovenous fistula (AVF) is an abnormal connection between an artery and a vein which may result from traumatic injury or may occur as congenital abnormality. Stent graft repair through arteriovenous fistula could lead to complications. CASE REPORT Endovascular stent graft repair in a 23-year-old patient with posttraumatic superficial femoral arteriovenous fistula was performed to cover a fistula. During the procedure the device migrated through the fistula into the femoral vein. Due to eventual risk of migration to the heart, a prompt decision was made to fix the stent graft with three puncture needles in the common femoral vein region under fluoroscopy guidance. The vascular surgeon was called to perform open surgery. CONCLUSIONS The presented way of treating this rare complication in an extreme and uncommon situation is very efficient, safe and inexpensive.