Earticle

As developing the medical treatment image portion with the change of these times, PACS, which is able to digitalize image portion data, has a lot of data-based image data. Applying this PACS, we would like to settle down RNSXI(real-name shooting X-ray of inspector) system. We interviewed with PACS's operators of university hospitals which is using PACS in Seoul about the present conditions whether using of RNSXI or not. And we inquired the RNSXI equipments, applying PACS database, and Interface conditions undertook to do in our hospital. All university hospitals in Seoul are set up the PACS system. But no hospital use the RNSXI. In our hospital, we can check inspector' name or initials who exposure x-ray with the PACS Viewer by looking over equipments(CR, DR, US, MG, MR, CT) and Interface of the DICOM Header data. However, some equipments like RF and Angio can not check inspector' name or initials. Under the Film/System environment, RNSXI system has been used frequently like that inspector's signature or initial added to a patient data. Though the digital medical treatment was developed, RNSXI system was declined. It is necessary to using RNSXI system in order to improving radiologists' rights, even if it is not under the application of the medical treatment image laws. If RNSXI system use, radiologists should specialize in their major and the Repeat rate should be reduced. In environment of PACS, RNSXI system can be used by linking both the equipments and the Interface with a production enterprise of PACS. Therefore RNSXI system applying the PACS datebase should settle down in our medical system for being provided lots of data.

We have evaluated and compared of gradient echo and spin echo EPI for compensating about deeply distortion aspect in case of post-operation patients in magnetic resonance image. A total of 100 patients were performed on 3.0 T(GE Signa Excite E2, USA) with 8ch head coil. As a result of analysis, The SNRs of whiter and gray matter areas were 36.74 ± 06 and 39.96 ± 09 in the gradient echo EPI, the SNRs which white and gray matter areas were slightly higher than gradient echo EPI(P<0.005, paired student t-test). It was 46.24 ± 11 and 51.38 ± 13 in gradient and spin echo EPI, respectively. The signal intensity in the whiter and gray matter areas also were 87.33 ± 15.24 and 140.66 土 13.45 in the gradient echo EPI techniques, The signal intensity of gradient echo EPI showed higher values compared to spin echo EPI. Otherwise, gradient echo EPI technique is distortion enough to operation wound and edge of the image, while spin echo EPI technique did not appear almost. In this point, the spin echo EPI technique, after surgical operation according to patient state beside gradient echo EPI techniques that signalbeside gradient echo EPI techniques that signal intensity is high and patient's case which image distortion is serious by metal etc, will be provide the useful information in adults and pediatric patients.

The purpose to recognize change of average pixel value of acquisition image by control panel's density and right set up method of speed(sensitivity) and exposure dose(mAs) change that dose in purpose digital flatpanel- detector. X-ray generator DHF—158H2(Hitachi，Japan). Detector CXDI 40G(Canon, Japan), 12 : 1 grid and exposure ray 135 kVp, 250 mA, 10 ms. focus-detector distance 180 cm and used ABC mode. DICDM reflex analysis program used image J that is digital reflex analysis program that offer in United States America National Health Center(National Institutes of Health : NIH) phantom used chest phantom(Anthromorphic : Flukebrome.inedical USA). An experiment chest phantom that consist by formation equivalence material use because density value(-3~+3) in X-ray control panel and seep that is speed step(slow, medium, fast) each control experimentalize, image analysis reflex neted through an experiment using image j each image compare. These was change in dose according to slow, medium, fast and density's change in an experiment result. According to detector sensitivity and density condition set, dose was relationship dissimilarity 500% from 200%. The dose came highest when is density +3 to slow, and dose more increases gray scale’s extent could know that rise. Could know whether how equipment set is important through this experiment, cause of disease which change by digital radiography system forward is thought to increase more, it is considered that suitable education by this and continuous interest about equipment need absolutely.

This study attempts to propose an appropriate method of using digital medical imaging equipments, by studying the effects of automatic exposure control(AEC), grid ratio and the change of radiography distance on the patient dose and detector acquisition dose during the procedure of acquiring image through a digital medical imaging detector. The change of dose following the change of grid ratio's exposure and radiography distance was measured, by using an abdominal phantom organized with tissue equivalent materials in an amorphous silicon thin film transistor detecter installed with AEC. The case to use grid ratio 12 : 1, focal distance 180cm to radiography distance 110cm in AEC, the patient dose increased rather when we used grid ration 10 : 1, focal distance 110cm. When AEC was not used, the dose necessary for image acquisi仕on decreased as the grid ratio became higher and the distance became further, but detector acquisition dose was not reduced when it applied AEC. When purchasing digital medical imaging equipments, optional items such as AEC and grid shall be accurately selected to satisfy the use of the eqxiipments. Radiography errors made by radiation technologist and unnecessary patient dose can be reduced by selecting equipments with a radiography distance marker equipment when it did not apply AEC. These equipments can also be helpful in maintaining high imaging quality, one of the merits of digital detectors.

To evaluate the accuracy and extent in the localization of cerebral motor cortex activation using a gradient- echo echo planar imaging(GE-EPI) compared to spin-echo echo planar imaging(SE-EPI) on 3T MR imaging. Functional MR imaging of cerebral motor cortex activation was examined in GE-EPI and SE-EPI in five healthy male volunteers. A right finger movement was accomplished with a paradigm of 6 task and rest periods and the cross-correlation was used for a statistical mapping algorithm. We evaluated any sorts of differences of the time series and the signal intensity changes between the rest and task periods obtained with two techniques. The qualitative analysis was distributed with activation sites of large veins and small veins by using two techniques and was found that both the techniques were clinically useful for delineating large veins and small veins in fMRI. Signal intensity change of the rest and activation periods provided similar activations in both methods(GE-EPI : 0.93±0.11, SE-EPI : 0.80±0.15) but 仕le signal intensity in GE-EPI(133.95±15.76) was larger than in SE-EPI(74.5± 18.90). The average SNRs of EPI raw data were higher at SMA in SE-EPI(48.54±12.37) than GE-EPI(41.4±12.54) and at Ml in SE-EPI(43.24±11.77) than GE_EPI(38.27±6.53). The localization of activation voxds of the GE-EPI showed a larger vein but the SE-EPI generally showed small vein. Then the analysis results of the two techniques were used for a statistical paired student t-test. SE-EPI was found clinically useful for localizing the cerebral motor cortex activation on 3.0T, but showed a little different activation patterns compared to a GE-EPI. In conclusion, SE-EPI may be feasible and can detect true cortical activation from capillaries and GE-EPI can obtain the large veins in the motor cortex activation on 3T MR imaging.

In angiography, the global standard agreements of DICOM is lossless. But it brings on overload and takes too much store space in DICOM sever. Because of all those things we transmit images which is classified in subjective way. But this cause data loss and would be lead doctors to make wrong reading. As a result of that we try to transmit continued image(raw data) to reduce those mistakes. We got angiography images from the equipment(Allura FD20-Philips). And compressed it in two different methodsdossless & lossy fair), and then transmitted them to PACS system. We compared the quality of QC phantom images that are compressed by different compress method and compared spatial resolution of each images after CD copy. Then compared each image's data volume(lossless & lossy fair). We measured spatial resolution of each image. All of them had indicated 401p/mm. We measured spatial resolution of each image after CD copy. We got also same conclusion (401p/mm). The volume of continued image(raw data) was 127.8MB(360.5 sheets on average) compressed in lossless and 29.5MB(360.5 sheets) compressed in lossy fair. In case of classified image, it was 47.35MB(133.7 sheets) in lossless and 4.5MB(133.7 sheets) in lossy fair. In case of angiography the diagnosis is based on continued image(raw data). But we transmit classified image. Because transmitting continued image causes some problems in PACS system especially transmission and store field. We transmit classified image compressed in lossless But it is subjective and would be different depend on radiologist, therefore it would make doctors do wrong reading when patients transfer another hospital. So we suggest that transmit continued image(raw data) compressed in lossy fair. It reduces about 60% of data volume compared with classified image. And the image quality is same after CD copy.