The Induction of Hyperthermia in Rabbit Liver by means of Duplex Stainless Steel Thermoseeds

OBJECTIVE: To determine the heating characteristics of needle-shaped duplex stainless steel thermoseeds, and to evaluate their effectiveness in the induction of hyperthermia in rabbit liver. MATERIALS AND METHODS: Thermoseeds of the two different shapes, L-shaped for single doses of hyperthermia and I-shaped for in-vitro study and repeated hyperthermic induction, were prepared. For the in-vitro study, an I-shaped thermoseed 0.23 mm in diameter and 25 mm long was placed inside a plastic tube filled with water. Heat was applied for 30 minutes within an induction magnetic field, and during this time changes in temperature were recorded using three thermocouples. For the in-vivo study, fifteen New Zealand white rabbits were divided into five equal groups. An I-shaped or L-shaped thermoseed was inserted in each rabbit's liver, and then placed within the center of the magnetic induction coil during a 30-minute period of hyperthermia. The rabbits in the first group were sacrificed immediately after hyperthermia was induced once, while those in the other groups were sacrificed at 1, 3, and 7 days, respectively, also after one induction. The remaining three rabbits were sacrificed 4 days after three consecutive daily treatment sessions. The resected segments of liver were subsequently evaluated histopathologically for the extent of coagulation necrosis caused by heating of the thermoseed. RESULTS: The in-vitro study demonstrated that the temperature in the thermoseed, which was 25.9 degree C before heating and 54.8 degree C after heating, rose rapidly at first but progressively less rapidly as time elapsed. Light microscopic examination of the rabbits' livers revealed coagulation necrosis and infiltration by inflammatory cells around the insertion site of the thermoseed. The maximum diameter of coagulation necrosis was 2.81+/-1.68 mm, and this occurred in the rabbits that were sacrificed 7 days after heat induction. CONCLUSION: Needle-shaped duplex stainless steel thermoseeds show temperature-dependent-type heating characteristics, and in rabbit liver, induced coagulation necrosis of surrounding tissues after heat is applied for 30 minutes. These thermoseeds may thus be useful for the induction of interstitial hyperthermia.

Stress Fracture in Posterior Aspect of the Tibia

PURPOSE: To determine correlation between stress fracture of the posterior tibia and flexor digitorum longusmuscle injury caused by athletic or sporting activity during adolescence. MATERIALS AND METHODS: Eleven casesdiagnosed as stress fracture after X-ray and MR imaging of the lower leg were reviewed. With regard to eachfracture, the following features were noted: age, sex, and athletic or sporting activity of the patient, and site.Using MR imaging techniques, axial and sagittal T1 and T2 weighted images were obtained in all cases and T1-GdDTPA images in seven. RESULTS: The activities undertaken were running (n=3), football (n=2), ballet (n=2),taekwando (n=1), badminton (n=1), field hockey (n=1), and basketball (n=1). MR images revealed localized corticalthickness (n=11), linear intramedullary callus showing a low signal on T1 and T2 weighted images (n=9), marrowhyperemia (n=7), and flexor digitorum longus muscle injury showing a high signal on T1-Gd DTPA and T2 weightedimage (n=7). CONCLUSION: Stress fracture of the posterior tibia might be induced by flexor digitorum longusmuscle activity induced by athletic or sporting activities during adoleseence.

Measurement of Renal Cortical Thickness Using Spiral CT in Early Diabetic Nephropathy

PURPOSE: To compare the ratio of renal cortical thickness to renal parenchymal thickness in early diabetic nephropathy and in normal control group. MATERIALS AND METHODS: We performed spiral CT in 17 patients suffering from diabetic nephropathy without renal failure or renal atrophy. The normal control group consisted of 19 persons who were normal on renal function test and did not show any abnormality of the kidney. Renal cortical and parenchymal thicknesses were measured at renal hilum level perpendicular to the renal surface by electronic caliper on contrast-enhanced transverse scan demonstrating the cortical nephrogram phase. Using student's test, the difference in renal parenchymal and cortical thickness between the two groups was tested for statistical significance. RESULTS: There was no significant difference in renal parenchymal thickness between the two groups(P>0.05) ; the patient group had a thicker renal cortex than the normal control group however (P<0.05). The ratio of renal cortical thickness to parenchymal thickness in early diabetic nephropathy patients(Rt.:0.041+/-0.051, Lt.:0.382+/-0.053) was significantly higher than in the normal control group (Rt.:0.331+/-0.067, Lt.:0.323+/-0.064). CONCLUSION: The kidney of early diabetic nephropathy patients had a thicker renal cortex than normal kidney.

Measurement of Renal Cortical Thickness Using Spiral CT in Early Diabetic Nephropathy

PURPOSE: To compare the ratio of renal cortical thickness to renal parenchymal thickness in early diabetic nephropathy and in normal control group. MATERIALS AND METHODS: We performed spiral CT in 17 patients suffering from diabetic nephropathy without renal failure or renal atrophy. The normal control group consisted of 19 persons who were normal on renal function test and did not show any abnormality of the kidney. Renal cortical and parenchymal thicknesses were measured at renal hilum level perpendicular to the renal surface by electronic caliper on contrast-enhanced transverse scan demonstrating the cortical nephrogram phase. Using student's test, the difference in renal parenchymal and cortical thickness between the two groups was tested for statistical significance. RESULTS: There was no significant difference in renal parenchymal thickness between the two groups(P>0.05) ; the patient group had a thicker renal cortex than the normal control group however (P<0.05). The ratio of renal cortical thickness to parenchymal thickness in early diabetic nephropathy patients(Rt.:0.041+/-0.051, Lt.:0.382+/-0.053) was significantly higher than in the normal control group (Rt.:0.331+/-0.067, Lt.:0.323+/-0.064). CONCLUSION: The kidney of early diabetic nephropathy patients had a thicker renal cortex than normal kidney.

Treatment of Single Nodular Hepatocellular Carcinoma Using Combination Methods of Percutaneous Ethanol Injection Therapy and Subsequent Transcatheter Arterial Chemoembolization

PURPOSE: To evaluate the usefulness of combination therapy composed of percutaneous ethanol injection treatment and subsequent transarterial chemoembolization in the treatment of single nodular hepatocellular carcinoma(HCC). MATERIALS AND METHODS: A total of eight patients with single nodule hepatocellur carcinoma (+/-5cm)were treated with a combination of initial percutaneous ethonol injection therapy(PEIT) and, a week later, transcatether arterial embolization(TAE). CT was performed 3 weeks after TAE to assess whether or not lipidol uptake had occurred. If lipiodol was accumulated in the nodule, the necrotic rate of the tumor was calculated by the following equation: (initially observed tumor volume - volume of nodule in which lipidol uptake occurred)x100/Initially observed tumor volume. Follow-up CT scan was performed every third or fourth month to evaluate tumor growth or recurrence. RESULTS: A nodule in which lipidol uptake occurred was seen in four of the eight patients; in one of these, a tumor-confirmed by angiogaphic examination and laboratory data-recurred twelve months later. The mean necrotic rate of a tumor treated PEIT alone was 83%(range, 37%-100%). CONCLUSION: Although limited in numbers of cases we studied, use of combination therapy composed of PEIT and subsequent TAE, appears to be effective in achieving the high rate of tumor necrosis as well as in the evaluation of the tumor during follow-up.

Morphological Variation of the Kidney Secondary to Junctional Parenchyma on Ultrasound

PURPOSE: To evaluate the prevalance of morphological variation of the kidney secondary to junctional parenchyma, as well as to analyze the ultrasonographic features of junctional parenchyma. MATERIALS AND METHODS: Two hundred and eighty two kidneys of 141 patient without clinical or radiologic evidence of renal disease were prospectively analysed using ultrasound. In all patients, ultrasonograms were obtained in sagittal, coronal and transaxial planes. The kidney was considered to have morphological variation if the ulrasonogram demonstrated junctional parenchymal defect or line ; those showing such variation were classified as one of three types :continuous, discontinuous, or junctional parenchymal line or defect without junctional parenchyma. The prevalance and ultrasonographic features of the kidneys were evaluated. RESULTS: Morphological variation was noted in 71 cases(25%). the continuous type accounted for 54% of these, the discontinuous type for 38%, and junctional parenchymal defect or line without junctional parenchyma for 8%. In all cases, junctional parenchyma was located approximately at the junction of the upper and middle third of the kidny, and had the same echogenecity as the renal cortex. CONCLUSION: An understanding of the morphological variation of the kidney resulting from junctional renal parenchyma would be helpful in differentiating pseudo tumor from true renal neoplasm.

Role of Double-Phase Spiral CT for T Staging of Gastric Cancer: Radiologic-Pathologic Correlation

URPOSE: To evalvate the role of double-phase spiral CT for T staging of gastric cancers with radiologic-pathologic correlation. MATERIALS AND METHODS: Double-phase spiral CT images of 44 patients of gastriccancers proved by pathologic examination were retrospectively evaluated. We retrospectively classified spiral CTimages of gastric cancers ; classification was from S 0 to S 4 and was based on the degree of change in three multilayered patterns shown in normal gastric wall and whether or not tumor cells had invaded perigastric fattissue. Pathologic classification was based on the T staging of TNM classification for gastric cancers, and wethen correlated these results. RESULTS: In group S1, all of three cases(100%) were proved to be T1 and in groupS2, five(45.5%) of 11 cases were T2. Of five cases with S3 CT findings, three(60%) were proved to be T3s andtwo(40%) were T2. Of 22 cases with S4 CT findings, 19(86.4%) were T3p. Overall sensitivity, specificity, and accuracy were 60.3%, 88. 5%, and 86.9%, respectively. In 35 (79.5%) of the total of 44 cases, the lesions were more enhanced on venous than on arterial phase. CONCLUSION: The accuracy of double-phase spiral CT for T staging of gastric cancers was 86.9%, and in contrast to previous results for conventional or dynamic CT, this level of accuracy was thought to be relatively high. In conclusion, double-phase spiral CT images of gastric cancers were helpful in the diagnosis of T staging.

Intratumoral Gas Formation of HCC after Trancatheter Arterial Chemoembolization (TACE)

PURPOSE: To determine the factors predisposing to the intratumoral gas formation after TACE in the treatment of HCC. MATERIALS AND METHODS: A total of 176 pathologically or clinically proven patients with HCC on whom CT scan had been performed in 2 weeks to 3months after TACE were reviewed. The patients were classified in two groups; intratumoral gas-forming group(n=18) and non-gas forming group(n=158). Chi-square (X2) test was applied to analyze the factors influencing to gas formation. The radiological factors studied were the morphologic type and location of HCC, presence or absence of tumor capsule on CT, the degree of tumor vascularities, presence or absence of portal vein thrombosis, presence or absence of arterioportal shunt, and TACE catheterization method on angiegraphic examination and the duration of post-TAE fever. RESULT: Intratumoral gas foramtion after TACE occurred significantly in tumors with peripheral location or capsule on CT tumors with less vascularity or peripheral arterioportal shunt on angiegraphic examination, and TACE with selective catheterization method(p0.05). The average duration of fever sustained after TACE was longer in gas-forming group than those in non-gas forming group (p<0.05). CONCLUSION: TACE of HCC with weak collaterals or with peripherd prevent recanalization from collaterals has tendency to intratumoral gas form-his and prolonged fever duration.

Xeromammographic breast parenchymal patterns and their relationship to breast cancer

No abstract available.