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Copyright of Czech Radiology / Ceska Radiologie is the property of Czech Medical Association of JE Purkyne and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Czech Radiology / Ceska Radiologie is the property of Czech Medical Association of JE Purkyne and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Czech Radiology / Ceska Radiologie is the property of Czech Medical Association of JE Purkyne and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Czech Radiology / Ceska Radiologie is the property of Czech Medical Association of JE Purkyne and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective: Phase contrast sequence may be used to measure the flux of blood in vessels. The result might be, however, corrupted by many errors including partial volume effect (PVE), region of interest (ROI) contouring, and noise. In this study we aim to quantify the error and if possible to suggest a proper strategy to minimize it. Methods: Water flux was measured using a plastic flow phantom and changing the flow rate and spatial resolution which affects the PVE error. Signal-to-noise ratio (SNR) of magnitude images was used to estimate error caused by noise and a comparison to a statistical error from several measurements was made. Water flux in vitro and flux through aortal valve and sinotubular junction in vivo was also measured with undersized and oversized ROIs. Results: The PVE subsides as spatial resolution improves and as the difference between magnitude signal from flowing and static tissue decreases. The error of flow through aortal valve was estimated to be 0.45%. Noise affects random error (estimation 0.05%) less then flow fluctuations (0.25%). The ROI size underestimation may lead to a severe underestimation of flow (over 10%) and a small underestimation in the case of aortal valve flow to a mild overestimation (5%). In general, an overestimation of ROI size is also erroneous (6%), although not as severe as underestimation. Conclusion: The most relevant source of error out of the three sources examined is ROI contouring with overestimation being recommended over underestimation. The error resulting from the PVE is small compared to ROI contouring error. The error caused by noise is negligible compared to flow fluctuation. [ABSTRACT FROM AUTHOR]

This article contributes to 30. years anniversary of the first installation of the very first Czechoslovak magnetic resonance system (MR). It makes an effort to map some important local and global mile stones over three decade's long exciting way of clinical and scientific application of this amazing method. Albeit the contribution has not typical educative character it explains some basic physical relations which considerably formed the effort and the development of all parts of MR system. Therefore also this article is structured to cover the development of all MR components in historical context. But not to staying only in history the next important aspect is to bring a survey about today's modern capabilities of MR systems as well as to introduce new perspectives for future years. [ABSTRACT FROM AUTHOR]