Soo-Youn Ham

Atypical Radiological Manifestation of Pulmonary Metastatic Calcification

Metastatic pulmonary calcification refers to calcium deposition in the normal pulmonary parenchyma and this deposition is secondary to abnormal calcium metabolism. The most common radiologic manifestation consists of poorly-defined nodular opacities that are mainly seen in the upper lung zone. We present here a case of metastatic pulmonary calcification that manifested as atypical, dense, calcium deposition in airspaces within the previously existing consolidation in the bilateral lower lobes, and this process was accelerated by pneumoniacomplicated sepsis in a patient with hypercalcemia that was due to hyperparathyroidism.

Comparison between coronal reformatted images and direct coronal CT images of the swine lung specimen: assessment of image quality with 64-detector row CT

The aims of this study were to compare the image quality of coronal multiplanar reconstruction (MPR) images from axial spiral images with that of direct coronal spiral and sequential images, and to estimate and analyse the effect of an incremental change on the image quality using 64-detector row CT. 12 swine lungs were used. Five kinds of images from each lung specimen were obtained using 64-detector row CT. All images were analysed by categories and grades, and the direct coronal sequential images were used as the reference standard for the image quality. Statistical analysis was performed for the following categories: (i) inter-observer reliability, (ii) interaction between the observers and images, (iii) image analysis, (iv) anatomical structural analysis of each observer, (v) stair-step artefact and (vi) background noise. The overall image quality and the image quality of all anatomical structures of coronal MPR images with 0.67 mm slice increments were inferior to the image quality of the other images; this difference was statistically significant (p<0.05). Stair-step artefact was detected on coronal MPR images, and was more prominent on coronal MPR images with 0.67 mm slice increments than on coronal MPR images with 0.34 mm slice increments. The most severe background noise was detected on the direct coronal sequential images, but there was no significant difference between the direct coronal sequential images and the direct coronal spiral images. Background noise was least prominent on coronal MPR images with 0.67 mm slice increments. The increment process is important for improving the image quality of MPR images even when using 64-detector row CT. Coronal MPR images with 0.34 mm slice increments using 64-detector row CT showed a similar image quality to that obtained from the direct coronal images, and can be used instead. This means that the coronal MPR images obtained with 64-detector row CT could be as useful for evaluating the lung parenchyma as the axial high-resolution CT images.

P3-052: How to evaluation of the completeness of cryotherapy in an attempt to quantify initial treatment success

How to evaluation of the completeness of cryotherapy in an attempt to quantify initial treatment success Kang, Moon Chul1 Lee, Sung Ho1 Kim, Kwang Taik1 Ham, Soo-Youn2 Cho, Sung Bum2 1 Department of Cardiothroacic Surgery, Anam Hospital, Korea University, Seoul, Korea 2 Department of Radiology, Anam Hospital, Korea University, Seoul, Korea Background: Immediate evaluation is possible for the percutaneous CT-guided cryosurgery by estimation of Hounsfield units, the size of formed ice-ball, and the percentage of tumor area covered by ice-ball. But, this method is not useful for the patient underwent fluoroscopyguided or video-assisted thoracosopic cryosurgery. And, the majority of the lesions are turned into cavitary lesion or necrotic area in the early postoperative periods. So, the aim of this study is to identify the methods and ideal time for the evaluation of the completeness of cryotherapy in an attempt to quantify initial treatment success. Methods: 52 pulmonary tumors in 34 consecutive patients (29 men and 5 women, median age 63 years, age range; 25-80 years) were treated by cryosurgery. Of the 52 pulmonary masses, 29 masses were primary lung cancers, and 23 masses were metastatic lung cancers. Cryosurgery was performed under computed tomographic, fluoroscopic or video-assisted thoracoscopic guidance. Cryoablation was performed as one or two cycles of 20-minute freeze followed by 5-minute thaw. Follow up chest CT scanning was taken at postoperative 1 month, 3 months and 6 months. We measured the area and Hounsfield units of the mass with computed tomography. And we compare the measured value respectively. Results: The measured area of the mass is ranged from 141.8mm2 to 3996.8mm2 preoperatively (postoperative 1 month; 66.8-8481.8mm2, 3 months; 32.6-4841.7mm2, 6 months; 45.6-4572.2mm2). The Hounsfield unit is ranged from 32 to 98 preoperatively (postoperative 1 month; 871, 3 months; 24-68, 6 months; 26-98). And, the decrease of the Hounsfield unit of 1 month showed good correlation of the reduction of the area of mass at postoperative 6 months (p-value=0.14). On the contrary, between the change of the Hounsfield unit and the change of the area of mass at 3 months or 6 months showed no correlation statistically. Conclusion: Postoperative computed tomographic scanning with measurement of Hounsfield unit at postoperative 1 month may be useful for the evaluation of the completeness of cryotherapy in an attempt to quantify initial treatment success.