PURPOSE: To date, the high spatial frequency algorithm (HSFA) which reduces image smoothing and increases spatial resolution has been used for the evaluation of parenchymal lung diseases in thin-section high-resolution CT. In this study, we compared the ultrahigh spatial frequency algorithm (UHSFA) with the high spatial frequency algorithm in the assessment of thin section images of the lung parenchyma. METHODS AND MATERIALS: Three radiologists compared the UHSFA and HSFA on identical CT images in a line-pair resolution phantom, one lung specimen, 2 patients with normal lung and 18 patients with abnormal lung parenchyma. RESULTS: Scanning of a line-pair resolution phantom demonstrated no difference in resolution between two techniques but it showed that outer lines of the line pairs with maximal resolution looked thicker on UHSFA than those on HSFA. Lung parenchymal detail with UHSFA was judged equal or superior to HSFA in 95% of images. Lung parenchymal sharpness was improved with UHSFA in all images. Although UHSFA resulted in an increase in visible noise, observers did not found that image noise interfered with image interpretation. The visual CT attenuation of normal lung parenchyma is minimally increased in images with HSFA. The overall visual preference of the images reconstructed on UHSFA was considered equal to or greater than that of those reconstructed on HSFA in 78% of images. CONCLUSION: The ultrahigh spatial frequency algorithm improved the overall visual quality of the images in pulmonary parenchymal high-resolution CT.
Humans ; Lung Diseases ; Lung* ; Noise

PURPOSE: The chemoembolization with Lipiodol and doxorubicin hydrochloride is used in patients with hepatocellular carcinoma. What condition is the ideal emulsion of Lipiodol and doxorubicin for excellent anticancer effect? METHOD AND MATERIALS: Microscopic evaluation was performed on the emulsions, which were varied with different specific gravities of doxorubicin solutions, degrees in mixing of the emulsion, and amount of Lipiodol. RESULT: 1. Maximal amount of doxorubicin solution was contained in Lipiodol droplets and the release of doxorubicin from the droplets were delayed, when specific gravity of doxorubicin was equal to that of Lipiodol (SG, 1.28). 2. The optimal therapertic ratio of Lipiodol and doxorubicin was 3:2 at least, as in the emulsion less than 3:2, unmixed free forms of doxorubicin solution were increased. 3. The emulsion mixed by pumping 50--100 times had smaller Lipiodol droplets and contained larger amount of doxorubicin solution in the droplets than by pumping 20 times. CONCLUSION: We recommend the emulsion with specific gravity of doxorubicin equal to Lipiodol (SG. 1.28), the ratio of Lipiodol and doxorubicin closo to 3:2, and the mixture prepased with puming 50--100 times.
Carcinoma, Hepatocellular* ; Doxorubicin ; Emulsions ; Ethiodized Oil ; Humans ; Specific Gravity

No abstract available.
Bone Regeneration* ; Bone Substitutes*

No abstract available.
Colon* ; Rectum*

No abstract available.

BACKGROUND: It has been a standard practice in many institutions to combine light general anesthesia with epidural block for abdominal and pelvic surgery. We attempted to prove the effectiveness of prehydration and to find an suitable epidural local anesthetic dose in terms of hemodynamic stability for upper abdominal surgery. METHODS: For preliminary studies, 11 patients scheduled for elective upper abdominal surgery had received general anesthesia immediately after epidural anesthesia. After epidural injection of 10~16 mL of 2% plain lidocaine into the T9~10 intervertebral space, the changes in blood pressure were observed. Thirty-two patients scheduled for elective upper abdominal surgery were divided into two groups. In group A (study group), after prehydration with Hartmann solution (10 mL/kg), 5~7 mL of 2% plain lidocaine was injected into T8~9 or T9~10 intervertebral space and general anesthesia was then induced. Group B (control group) received general anesthesia only. RESULTS: There were no significant differences in hemodynamics between the epidural with general anesthesia and the control group except SVR (systemic vascular resistance). SVR in group A increased in contrast to the group B in which it remained unchanged. CONCLUSIONS: The combined epidural and general anesthesia, using prehydration and 0.5~1 mL/segment of 2% plain lidocaine at the T8~9 or T9~10 intervertebral space was safe without significant hemodynamic changes.
Anesthesia, Epidural ; Anesthesia, General* ; Blood Pressure ; Hemodynamics* ; Humans ; Injections, Epidural ; Lidocaine

Magnetic resonance imaging(MRI)has proved to be a valuable method for evaluation of the head and neck. Unfortunately, metallic devices associated with certain dental fillings and applicances often cause variable artifacts that can obscure normal or pathologic conditions on MR and computed tomography. In this work, we assessed the MR appearance of dental prosthetic materials in vitro and in vivo including precious alloys. Nonprecions alloys, resin, amalgam and titanium alloy, For in vivo studies, these materials were placed in healthy volunteer's mouths and then images were assesed. Analyis of the appearance of shape and extent of artifact,and observed influence of these artifacts on the image interpretation at 0.2 Tesla permanent type MR scanner were valuated. Material used as temporary or permanent filling of crowns such as amalgam. precious alloy and, microfilled resin did not cause artifact on the image. The size of the artifact produced by the nonprecious alloys was influenced by the ferromagnetism of the object and the volume prosthesis, and was related to the scanning sequence. Nonprecious alloys produced minimal local signal distortions, where precious alloys, and dental resin had no effect on the MR image in vivo. These results were mainly from a low field strength MR scanner used in this study.
Alloys ; Artifacts* ; Crowns ; Dental Materials* ; Equidae ; Head ; In Vitro Techniques ; Magnetic Resonance Imaging* ; Magnets ; Methods ; Mouth ; Neck ; Prostheses and Implants ; Resins, Synthetic ; Silicone Elastomers ; Titanium

No abstract available.
Orbit*

No abstract available.
Mediastinum* ; Neuroblastoma*

The anatomical variations of 112 hypophysis and diaphragma sellae in Korean adult cadavers and coronal CT were studied. 1) The hypophysis was classified 4 types based on superior view. 2) The superior surface of the hypophysis was concave(65.9%) in cadavers and flat(55.3%) in CT. 3) The neural lobe was placed on the center of the posterior surface of the anterior lobe(72.3%). 4) The hypophysis was compressed by the internal carotid artery in 9.6%. 5) The mean A-P length, width and height of the hypophysis were 10.4mm, 14.2mm and 4.8mm in cadavers, respectively. The mean width and height in CT were 13.2mm and 5.0mm, respectively. 6) The width of the hypophysis was significantly different between man and woman. 7) The diaphragma sellae was concave or flat. 8) The diaphragmatic line was average 13.9mm in man and 14.6mm in woman. 9) The diaphragmatic foraman was circular or oval and the A-P diameter was greater than transverse one. 10) Type IIb that diaphragma sellae and hypophysis were concave according to Busch(1951) was 40.4%. 11) The empty sella was found in 14.4%.
Adult* ; Cadaver* ; Carotid Artery, Internal ; Female ; Humans ; Pituitary Gland* ; Pituitary Gland, Posterior