1.Vascular Nature of Liver Abscess Examined with Computed Tomography: Separated Identification of the Four Layers and Difference According to the Various Factors of Abscess.
Jae Chun CHANG ; Hyun Cheol CHO ; Jung Kon KOH
Journal of the Korean Radiological Society 1994;31(2):321-326
PURPOSE: To identify the four layers based on intranodular vascular nature visible in multiphase incremental bolus dynamic CT and to determine any differential points according to various factors of liver abscess with this vascular nature or not. MATERIALS AND METHODS: We categonized 29 cases of confirmed liver abscess into three different groups according to presence of four layers visible in early phase(arterial phase) of CT. Three groups were compared in regard to the results of antiamebic antibody test and bacteriologic study and presense of cholangitic abscess and internal septation. RESULTS: We could separate four layers, innermost hypodense central cavitary lesion, hyperdense granular tissue, hypodense abscess wall and outermost hyperdense compensatory hypervascular zone in 18 cases(62%), only two layers, cavity and wall in six cases(21%), and characteristically we could find three layers without innermost cavitary lesion in five cases(17%). But we couldn't find significant correlations between various clinical factors of liver abscess and our vascular groups. CONCLUSION: Our method of CT could represent four layers based on vascularity in 62% of cases. And also could find the unusual inflammatory mass containing three layer which must be differentiated from other malignant solid mass. But we couldn't find differential point between various clinical factor of liver abscess and imaging diagnosis. We think that with the improvement of hardware such as spiral CT, identification of four layers will be earier and will be very helpful in early detection and proper treatment planning of liver abscess.
Abscess*
;
Diagnosis
;
Liver Abscess*
;
Liver*
;
Tomography, Spiral Computed
2.Influence of Thickness of Empress 2 Ceramic on Fracture Strength.
Jung Woo KOH ; Jae Ho YANG ; Sun Hyung LEE
The Journal of Korean Academy of Prosthodontics 2000;38(4):446-460
All ceramic restorations have had a more limited life expectancy than metal ceramic crowns because of their lower strength. The relatively lower strength has limited the use of all-ceramic crowns to the areas where occlusal loads are lower. Therefore many researches have been done to increase the strength of all-ceramic crowns. IPS Empress 2 is a new type of lithium disilicate glass-ceramic with enhanced physical characteristics which has been in use clinically since 1998. Previous researches reported that the flexural strength of all-ceramic material was greater than 300MPa, and all-ceramic crowns can be used in staining or layering technique. The objective of this study was to investigate the influence of the thickness of IPS Empress 2 ceramic on fracture strength. Both staining technique and layering technique was investigated. Vita VMK was used as control. For all three groups, five specimens each of 0.8mm, 1.0mm, 1.4mm, 1.8mm, and 2.2mm thickness (a total of 75 specimens) were prepared. Control group: Vita VMK Porcelain specimens were prepared with dentine ceramic and liquid glazing was done. Group I: IPS Empress 2 were prepared with staining technique and stained twice and glazed once. Group II : IPS Empress 2 were prepared with layering technique and glazed after wash firing. The thickness and diameter of the specimen were measured and controlled after specimen preparation. Biaxial Flexure Test (ASTM Standard F394-78) was adopted as this test method produces results least affected by the edge condition of the specimens. Fracture strength was measured with Instron Universal Testing Machine. Conclusions are as follow : 1. The fracture strength was increase in order of control group, test group I, test group II. 2. Fracture strength of the group I(Empress 2 Staining) was 65.54 N in 0.8mm, 155.2 N in 1.0mm, 233.5 N in 1.44mm, 434.5 N in 1.8mm, and 600.1 N in 2.2mm. 3. Fracture strength of the group II (Empress 2 Layering) was 190.0 N in 0.8mm, 283.5 N in 1.0mm, 437.2 N in 1.4mm, 732.0 N in 1.8mm, and 1115.0 N in 2.2mm. 4. No statistical difference was found in flexural strengths according to thickness in a specified group(p>0.05).
Ceramics*
;
Crowns
;
Dental Porcelain
;
Dentin
;
Fires
;
Life Expectancy
;
Lithium
3.Comparison of portal CT and indirect portography in hepatic masses.
Jung Kon KOH ; Jae Chang CHANG ; Bok Hwan PARK
Journal of the Korean Radiological Society 1993;29(2):255-261
We compared 87 portographic filling defects detected by portal CT in 64 patients were compared with those obtained by indirect portography. The indirect portography could visualize portogram only in anterior-posterior view. But the portal portal CT could visualize both portogram and hepatogram. We examined the portal CT and indirect portography and compared the accuracy of the both methods to evaluate the limitation and significance of the indirect protography. The mass shape lesions were seen on the portal CT which means portal flow defects of the mass lesions only could not depict totally in indirect portography (0%, 0/41). And the larger defects than real mass lesion were seen in portal CT means mass with associated portal flow defect and find portal vein invasion around the mass in 52% (24/46) of the indirect portography. Among them, only 66% of mass were detected correctly in the indirect portography comparing with mass lesion in portal CT. In summary, indirect portogram could not detect small filling defects which detected in portal CT and could not depict the extent of large filling defects. It also could not visualize correctly the protal flow in non-lesion side of the liver parenchyma.
Humans
;
Liver
;
Portal Vein
;
Portography*
4.NO2- and ATP synthesis in the EMT-6 cell stimulated by mercury chloride.
Gyung Jae OH ; Dai Ha KOH ; Jung Ho YOUM
Korean Journal of Preventive Medicine 1996;29(3):495-506
Effect of Mercury chloride on the synthesis of NO2- and ATP were observed in EMT-6 cells which were culture with cytokines(IL-1alpha and IFN-gamma) and various concentrations of mercury chloride from 0.05 to 0.08 M. Viability of EMT-6 cells were observed above 90% in almost groups. There were not significant differences in the viability between mercury supplemented groups and control group. It suggests viability of EMT-6 cells were not influenced by these concentrations of mercury chloride. Results of the synthesis of nitrite showed significant time and group effect. There is a significant interaction effect between concentration of mercury chloride and culture time. The effect of various concentration of mercury chloride is not the same for all levels of culture time. There were significant differences in the synthesis of nitrite between mercury chloride supplemented groups and control group, and the synthesis of nitrite in EMT-6 cell by the supplement of mercury chloride was significantly decreased in a dose-dependent manner. Results of the synthesis of ATP showed a significant group effect, and the time main effect and the Group x Time interaction were also significant. There were significant differences in the synthesis of ATP between mercury chloride supplemented groups and control group, and the synthesis of ATP in EMT-6 cell by the supplement of mercury chloride was significantly decreased in a dose-dependent manner. These results suggest that the disorder of cell mediated immunity by mercury chloride could be related to the inhibition of nitric oxide synthesis which will be caused by the decreased synthesis of ATP.
Adenosine Triphosphate*
;
Immunity, Cellular
;
Nitric Oxide
5.Biomechanical evaluation of dental implants with different surfaces: Removal torque and resonance frequency analysis in rabbits.
Jung Woo KOH ; Jae Ho YANG ; Jung Suk HAN ; Jai Bong LEE ; Sung Hun KIM
The Journal of Advanced Prosthodontics 2009;1(2):107-112
STATEMENT OF PROBLEM: Macroscopic and especially microscopic properties of implant surfaces play a major role in the osseous healing of dental implants. Dental implants with modified surfaces have shown stronger osseointegration than implants which are only turned (machined). Advanced surface modification techniques such as anodic oxidation and Ca-P application have been developed to achieve faster and stronger bonding between the host bone and the implant. PURPOSE: The purpose of this study was to investigate the effect of surface treatment of titanium dental implant on implant stability after insertion using the rabbit tibia model. MATERIAL AND METHODS: Three test groups were prepared: sandblasted, large-grit and acid-etched (SLA) implants, anodic oxidized implants, and anodized implants with Ca-P immersion. The turned implants served as control. Twenty rabbits received 80 implants in the tibia. Resonance frequencies were measured at the time of implant insertion, 2 weeks and 4 weeks of healing. Removal torque values (RTV) were measured 2 and 4 weeks after insertion. RESULTS: The implant stability quotient (ISQ) values of implants for resonance frequency analysis (RFA) increased significantly (P < .05) during 2 weeks of healing period although there were no significant differences among the test and control groups (P > .05). The test and control implants also showed significantly higher ISQ values during 4 weeks of healing period (P < .05). No significant differences, however, were found among all the groups. All the groups showed no significant differences in ISQ values between 2 and 4 weeks after implant insertion (P > .05). The SLA, anodized and Ca-P immersed implants showed higher RTVs at 2 and 4 weeks of healing than the machined one (P < .05). However, there was no significant difference among the experimental groups. CONCLUSION: The surface-modified implants appear to provide superior implant stability to the turned one. Under the limitation of this study, however, we suggest that neither anodic oxidation nor Ca-P immersion techniques have any advantage over the conventional SLA technique with respect to implant stability.
Dental Implants
;
Imidazoles
;
Immersion
;
Nitro Compounds
;
Osseointegration
;
Rabbits
;
Tibia
;
Titanium
;
Torque
6.Evaluation of hepatic masses by angio-CT.
Jae Chun CHANG ; Jung Kon KOH ; Bok Hwan PARK ; Chang Mo GU ; Sang Young KIM
Journal of the Korean Radiological Society 1992;28(4):593-600
Authors performed angio-CT(portal &/or arterial CT) in 35 patients with various hepatic masses. We obtained portal CT in 32 and arterial CT in 13 patients. The contrast material was injected into superior mesenteric artery for portal CT and into hepatic artery for arterial CT after transfemoral cathetrization of these arteries. We concluded that portal CT was superior to other imaging modalities highly sensitive in detecting hepatic masses, especially, early hepatocellular carcinomas, daughter nodules, and subclinical metastatic hepatic malignancy, With this method, detection rate of early hepatocelluar carcinomas improved 62% in number of patients and 90% in number of masses. Detection rate of subclinical hepatic metastases improve 60% each in number of patients and in number of masses. It was also useful for the detection of portal vein invasion. Arterial CT was useful in differential of masses and in defining the characteristics of entire or part of the masses because this method revealed hemodynamic patterns more definitely.
Arteries
;
Carcinoma, Hepatocellular
;
Hemodynamics
;
Hepatic Artery
;
Humans
;
Mesenteric Artery, Superior
;
Methods
;
Neoplasm Metastasis
;
Nuclear Family
;
Portal Vein
7.Clinical Results of Modified Ab Externo and One-Knot Technique.
Journal of the Korean Ophthalmological Society 2012;53(12):1783-1788
PURPOSE: To introduce a more efficient and time-saving scleral fixation technique for a posterior chamber foldable intraocular lens and to report the clinical results. METHODS: A foldable acrylic 3-Piece IOL was sutured to the sclera via a small corneal incision. The guiding hollow needle was not used, which differs from other ab externo techniques. Instead, the curved long needle was directly pulled out through the cornea. The scleral flap was not used to bury the scleral suture knot; Instead, the scleral suture knot was translocated at the temporal area. RESULTS: A total of 30 cases were studied retrospectively. The mean follow-up period was 2 years. The IOL was correctly positioned in all cases. There were no major complications, such as endophthalmitis or suture erosion through the conjunctiva. CONCLUSIONS: Based on the authors' experience, the modified ab externo and one-knot technique is a faster and easier technique than the conventional ab externo technique.
Cornea
;
Endophthalmitis
;
Follow-Up Studies
;
Lenses, Intraocular
;
Needles
;
Retrospective Studies
;
Sclera
;
Sutures
8.Clinical Results of Modified Ab Externo and One-Knot Technique.
Journal of the Korean Ophthalmological Society 2012;53(12):1783-1788
PURPOSE: To introduce a more efficient and time-saving scleral fixation technique for a posterior chamber foldable intraocular lens and to report the clinical results. METHODS: A foldable acrylic 3-Piece IOL was sutured to the sclera via a small corneal incision. The guiding hollow needle was not used, which differs from other ab externo techniques. Instead, the curved long needle was directly pulled out through the cornea. The scleral flap was not used to bury the scleral suture knot; Instead, the scleral suture knot was translocated at the temporal area. RESULTS: A total of 30 cases were studied retrospectively. The mean follow-up period was 2 years. The IOL was correctly positioned in all cases. There were no major complications, such as endophthalmitis or suture erosion through the conjunctiva. CONCLUSIONS: Based on the authors' experience, the modified ab externo and one-knot technique is a faster and easier technique than the conventional ab externo technique.
Cornea
;
Endophthalmitis
;
Follow-Up Studies
;
Lenses, Intraocular
;
Needles
;
Retrospective Studies
;
Sclera
;
Sutures
9.Coexisting Adenocarcinoma and Epithelioid Leiomyosarcoma of Stomach: A case report.
Jung Youn KIM ; Jae Soo KOH ; Kyung Ja CHO ; Ja June JANG
Korean Journal of Pathology 1995;29(4):521-523
We report a case of malignant tumor of the stomach showing both carcinoma and sarcoma components in a 47 year-old woman. The resected stomach revealed two tumors which were in different location. The one mass was a 2 x I cm, poorly demarcated tumor at the body, along the lesser curvature and the other was a 6 x 7 cm, well demarcated polypoid tumor with a central depression at cardia of the posterior stomach wall. The tumor at the body was a poorly differentiated adenocarcinoma which showed strong reactivity for CEA. The tumor at the cardia was composed of epithelioid or spindle shaped cells with abundant eosinophilic cytoplasm and revealed 5-6 mitoses per ten high power field. The tumor at the cardia was diagnosed as epithelioid leiomyosarcoma and showed reactivity for vimentin but none for actin, desmin,keratin, and CEA. This is different from the usual carcinosarcoma.
Female
;
Humans
;
Adenocarcinoma
10.A Case of Neurocutaneous Melanosis in a 46-year Old Man.
Sung Eun CHANG ; Hwa Jung LEE ; Jae Hee SEO ; Jai Kyoung KOH
Annals of Dermatology 1997;9(4):293-297
Neurocutaneous melanosis is a very rare congenital syndrome characterized by the presence of large or multiple congenital melanocytic nevi and benign or malignant melanotic tumors of the central nervous system. We report herein a case of neurocutaneous melanosis with leptomeningeal melanosis and a malignant melanoma of the right temporal lobe in a 46-year old man. The case is exceptional as regards the late onset of symptoms and death. Even without a malignant melanoma, the symptomatic neurocutaneous melanosis has a fatal course. The syndrome is rare but lethal, so the dermatologist should be aware of this syndrome when evaluating the patients with large or numerous congenital melanocytic nevi so as to watch for the usual signs of increased intracranial pressure and to take prompt palliative measures.
Central Nervous System
;
Humans
;
Intracranial Pressure
;
Melanoma
;
Melanosis*
;
Nevus, Pigmented
;
Temporal Lobe