[INTRODUCTION - Modern radical radiotherapy can be an effective alternative of radical prostatectomy in low risk patients with prostate tumor. Our objective was to demonstrate the feasibility of transperineal MR-guided prostate interventions in an open MR unit and to present our early clinical experiences on canines. METHODS AND MATERIALS - The procedures were performed on 5 canines in an open-configuration 0.35T MR scanner. For interventions an MR compatible custom-made device was used. The canines were placed in the right lateral decubitus position. Template reconstruction, trajectory planning, target and OAR delineation were based on T2 FSE images. For image guidance and target confirmation, fast spoiled gradient-echo (FSPGR) sequence was used. MR compatible coaxial needles were inserted through the perineum to the base of the prostate. After satisfactory position was confirmed, brachytherapy catheters were placed through the coaxial needles, which were then removed. RESULTS - Mean and standard deviation of the needle displacements was 2.2 mm±1.2 mm, with a median of 2 mm. 96% of the errors were less than 4.0 mm. Implantation induced prostate motion was measured with a mean of 10.3 and 2.3 mm in cranio-caudal and transverse directions. Significant movement was only observed during the first 4 needle insertions. The average time needed for each step was: anesthesia 15 minutes, setup and positioning 15 minutes, initial imaging 15 minutes, template registration and projection 15 minutes, contouring, trajectory planning, insertion of 10 needles 60 minutes. CONCLUSION - Based on our canine model experiences our method seems to be a promising approach for performing feasible, accurate, reliable and high-quality prostate MR guidance within a reasonable time span. We plan to introduce MR-guided biopsy and brachytherapy in human patients in the near future.]

[INTRODUCTION - The multidetector CT-technology made the application of perfusion CT-examination in the diagnosis of vascular brain damages possible in recently. The purpose of this study was to introduce the method and to assess the importance of computed tomography brain perfusion in emergency patient care and early diagnosis of brain ischemia. PATIENTS AND METHODS - We perform brain perfusion examinations with a 2 slice multidetector computer tomography (General Electric Highspeed NX/i, 2004) in our hospital. We examined the results of native and perfusion CT of 27 patients who underwent CT brain perfusion examination during emergency patient care in our department between 2004 January and 2006 December. We also examined if the patients got systemic thrombolysation and the patients’ condition after therapy. RESULTS - The perfusion software can make quantitative colour maps of parameters (CBF, CBV, MTT) and can visualize mean value and percentil decrease of measuring parameters. There were 18 positive and 8 negative CTbrain perfusion examinations in the examined period. One examination was technically unvaluable. CONCLUSION - By measuring blood flow's decrease the CT-brain perfusion examination can separate the reversible and irreversible damage of brain parenchyma. The examination protocol of brain vascular damages are native CT-scan, postcontrast perfusion CT-examination and CTangiography by the recommendation of international literature. Despite the multidetector CT-s and CT-perfusion technic is available for years, the CT-brain perfusion examination is not a routine process in the emergency patient care in our country.]