Hepatocellular Carcinoma after Radiofrequency Ablation: Recurrent Pattern and Influenting Factor

PURPOSE: To evaluate patterns of recurrence and factors which influence them in radiofreqency (RF) ablation for the treatment of hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Between May 1999 and March 2000, 69 patients with 82 HCCs underwent RF ablation for complete necrosis. They were diagnosed by tissue biopsy or tumor marker, and the results of triphasic spiral CT. The indications were that nodular lesions were clearly visualized at sonography, less than 5 cm in size and less than four in number, and that patients had no history of previous treatment. Local therapeutic efficacy such as complete necrosis and marginal recurrence, and new lesions were evaluated by means of triphasic spiral CT performed at least six months after the completion of ablation. We then analyzed the correlation between local therapeutic efficacy and various influential factors such as tumor size, whether the tumor was attached to the portal vein, gross morphology, Child-Pugh classification, and alpha- fetoprotein level before the procedure, as well as the correlation between new lesions and influential factors which included the alpha-fetoprotein level before the procedure, Child-Pugh classification, and multiplicity per person. RESULTS: During a mean follow-up period of 8.95 (range, 6-14) months after RF ablation, the rate of complete necrosis and of marginal recurrence was 91% and 12%, respectively. When a tumor was larger and was attached to a large branch of the portal vien, the incidence of incomplete necrosis and marginal recurrence was greater. The occurrence rate of new lesion was 19.4%. When the alpha-fetoprotien level before the procedure was higher and a tumor was multiple in number, new lesions occurred more frequently. CONCLUSION: Sufficient knowledge of patterns of recurrence and the factors which influence them might improve the therapeutic effects of RF ablation in patients with HCC.

The Effect of Embolotherapy for Acute Gastrointestinal Bleeding in Patient with Coagulopathy

PURPOSE: To analyse the causes of coagulopathy and determine the effect of embolotherapy on acute gastrointestinal(GI) bleeding coexisting with coagulopathy. MATERIALS AND METHODS: Between June 1991 and December 1998, 29 patients with acute GI bleeding (M:F =21:8, mean age, 57.8 years) underwent percutaneous embolotherapy and immediate cessation of bleeding was confirmed. The patients were divided into two groups: control (n =16) and those with coagulopathy (n =13), group membership being determined according to the criteria of >+/-2SD of normal prothrombin time (PT) and activated partial thromboplastin time (aPTT) ( PT >23 seconds, aPTT >40 seconds) at the time at which embolization was requested. Embolotherapy was, defined as clinically successful, if the patient was stable for at least three days, without bleeding, after technically successful embolization. The clinical success rate of embolization and the mortality rate were compared between the two groups, and the causes of coagulopathy statistically analysed. RESULTS: The clinical success rate of embolization was 75% (n =12) in the control group, compared with 38.5% (n =5) in the coagulopathic group (p < 0.05), while the mortality rate for the two groups was 6.3% (n =1) and 53.8% (n =7), respectively (p < 0.005). Statistically, massive transfusion and sustained shock before embolization were the causes of coagulopathy (p < 0.05). CONCLUSION: In coagulopathic patients with acute GI bleeding, embolotherapy induces transient bleeding control, but is unlikely to save lives.

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.

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.

Necessity of Site-specific BMD Measurements using Dual X-ray Absorptiometry

PURPOSE: To determine the necessity of site-specific bone mineral density(BMD) measurement and the difference between the BMD of the two femora using DXA in the evaluation of osteoporosis. MATERIALS & METHODS: Total BMD and regional BMD(Lumbar spine, femoral neck, Ward's area, intertrochanter area) were measured on seventy-eight healthy persons without previons diseases, and the statistical significance analyzed. RESULTS: Total BMD did not reliably reflect the site-specific BMD. There was a high correlation between BMD in opposing femora. Correlation coefficients between the femoral neck, Ward's area, trochanter area were 0. 939, 0.874 and 0.916 respectively. CONCLUSION: We conclude that a measuremnt of site-specific BMD is necessory because the total BMD can not reliably predict the regional BMD. The measurement of BMD in one femur can predict the BMD of the contralateral femur. If there is no history of femoral neck disease, unilateral BMD measurement is recommended for femoral evaluation.

Multiple Bile-duct Hamartoma: Two Case Report

Authors report the radiologic findings of two cases of multiple bile-duct hamartoma in the liver. Ultrasonography and computed tomography of the liver were performed in two female patients. In one patient, ERCP was performed. Ultrasonography and computed tomography showed scattered multiple hypoechoic and low attenuated lesions, measuring up to 2cm in both lobe and ERCP showed communication of these lesions with the biliary system. Multiple bile-duct hamartoma should be included in the differential diagnosis of multiple small cystic lesions in the liver.

MRI of Spinal Tuberculosis

PURPOSE: To assess the characteristic features of MR imaging in the diagnosis of spinal tuberculosis. MATERIALS AND METHODS: We retrospectively reviewed MR imaging of 27 cases with pathologically-proven spinal tuberculosis and analyzed the MR findings including the extent of the lesions on non-contrast T1, proton density, and T2*VI, and the specific contrast enhancement patterns of the lesion on Gd-DTPA enhnced TIWI. RESULTS: The inflammatory lesions showed low signal intensity on T1WI in 25 patients(93%) and high signal intensity on T2*gradient echo image in 25 patients(93%). Bone destruction was noted in 15 patients(55%), disc-space narrowing in 21 patients(77%), paravertebral abscess in 16 patients(59%), subligamentous extension in 23 patients(85%), kyphosis in 8 patients(29%), and spinal canal narrowing in 19 patients(70%). After Gd-DTPA was administrated, rim-enhancement was noted in all patients(100%). CONCLUSION: We conclude that MR imaging is an excellent imaging modality for establishing the diagnosis of spinal tuberculosis as well as delineating the extent of soft tissue involvement. Characteristic peripheral rim enhancement after injection of Gd-DTPA may provide rather specific diagnosis in spinal tuberculosis.

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.

Pulmonary Lymphangitic Carcinomatosis: Correlation with High-Resolution CT Findings with Pulmonary Function Test

PURPOSE: To analyze high-resolution CT findings(HRCT) of pulmonary lymphangitic carcinomtosis(PLC) and to correlated the HRCT findings with the results of pulmonary function test(PFT). MATERIALS AND METHODS: In Twenty eight patients with radiologically and clinically proved PLC, we retrospectively reviewed HRCT scans and PFT(N=12). PLC was classified by extent and distribution of metastatic nodules and interstitial thickenings on HRCT and the findings were correlated with the results of PFT and impairment of PFT according to the degree of FEVl(forced expiratory volume in one second). RESULTS: On the basis of distribution of PLC, HRCT findings showed 20 cases of peripheral type, 3 cases of central type, and 5 cases of mixed type. In the patients with PFT diffuse type was 10 cases and localized type was 2 cases. In diffuse types, the restrictive pattern occurred in 7 cases (p<0.05) and in localized types, restrictive pattern occurred in 2 cases. Marked impairment of vital capacity was shown as restrictive pattern in 7 cases all of which were diffuse type and were consisted of peripheral type in 4 cases and mixed type in 3 cases. CONCLUSION: HRCT findings of lymphangitic carcinomatosis correlated well the type and degree of impairment of PFT. Especially in diffuse type of lymphangitic carcinomatosis, the result of pulmonary function test were prominent restrictive patterns. Marked impairment of pulmonary function occurred in patients with diffuse type and types with peripheral interstitial thickening(periphral and mixed types).

Computed Tomographic Findings of the Carcinoma of the Ampulla of Vater

OBJECTIVE:The purpose of this study is to evaluate the CT findings of the carcinoma of the ampulla of Vater and to differentiate from other periampullary carcinoma including the carcinoma of the distal common bile duct and pancreas head. MATERIALS AND METHODS: We retrospectively reviewed the CT findings of 13 cases of the carcinoma of the ampulla of Vater, 20 cases of the carcinoma of the distal common bile duct and 20 cases of the carcinoma of the pancreas head confirmed by pathology. Five millimeter consecutive settings of CT scan were performed in all cases on ampulla level with supine position. The CT findings were retrospectively evaluated in view of common bile duct dilatation, pattern of termination of bile duct, pancreatic duct dilatation, protruding mass in duodenal lumen, and regional lymph node metastasis. RESULTS: All case of the carcinoma of the ampulla of Vater(13/13) and distal common bile duct(20/20) showed common bile duct dilatation with abrupt termination. Among the 10 cases of the carcinoma of the pancreas head with common bile duct dilatation, five cases each had is abrupt termination(5/20) and gradual stenosis of bile duct(5/20). Five cases of the carcinoma of the ampulla of Vater(5/13) and four cases of the carcinoma of distal common bile duct(4/20) showed pancreatic duct dilatation and all cases of the carcinoma of pancreas head show pancreatic duct dialtation(20/20). Twenty cases of the carcinoma of the ampulla of Vater showed protruding mass in the medial wall of the second portion of the duodenum(12/13) but only one case of the carcinoma of the distal common bile duct(I/20) and five cases of the carcinoma of the pancreas head (5/20) had protruding mass in the duodenal lumen. Only one case of the carcinoma of the ampulla of Vater showed(1/13) regional lymph node metastasis but three cases of the carcinoma of the distal common bile duct(3/20) and 18 cases of the carcinoma of the pancreas head(18/20) showed regional lymph node metastasis. CONCLUSION: Common bile duct dilatation with abrupt termination, protruding mass in the duodenal lumen and rare lymph node metastasis in CT may suggest the carcinoma of the ampulla of Vater.

Differential Diagnosis of Degenerative Vertebral Endplate Changes and Diskitis in MRI

OBJECTIVE: The purpose of this study was to determine differential findings between Type I degenerative endplate changes and diskitis on MR images. MATERIALS AND METHODS: MR images(T1, T2 weighted or Gradient echo) of L-spine in twelve patients with a Type I degenerative endplate change and nine patients with diskitis were reviewed for the morphologic and signal intensity changes of intervertebral disc, vertebral endplate and vertebral body. RESULTS: involvement of the marrow of one side of intervertebral disk was noted in 33%(4/12) of Type I endplate changes, and 11%(1/9) of diskitis. Decreased signal intensity of intervertebral disc was seen in 92% (11/12) of Type I endplate changes, and 11%(1/9) of diskitis on T2 weighted or Gradient echo image. Loss of intranuclear cleft signal was noted in 17%(2/12) of Type I endplate changes, and 78%(7/9) of diskitis. Even disc space narrowing was seen in all cases of Type I endplate changes, but uneven narrowing was seen in 44%(4/9) of diskitis. Only partial cortical disruption was noted in 42%(5/12) of Type I endplate changes, while partial or total cortical disruption was noted in 89%(8/9) of diskitis. The extent of marrow involvement more than 2/3 was noted in 8%(1/12) of Type I endplate changes, but 56%(5/9) of diskitis. The margin of signal intensity change was well defined in 33%(4/12) of Type I endplate changes, but that of diskitis was ill defined in all cases(9/9). Gadolinium enhancement was homogeneous in all cases(5/5) of Type I endplate changes, and 63%(5/8) of diskiris. CONCLUSION: We conclude that involvement of one side of endplate, decreased signal intensity of intervertebral disc on T2 weighted or gradient echo image, even narrowing of disc space, lesser extent of marrow involvement, well defined margin and homogeneous enhancement pattern are the findings of Type I degenerative endplate changes on MR images.

MR Imaging of Meniscal Tears' Correlation with History of Trauma

PURPOSE: The medial meniscus is injured much more than the lateral meniscus. Because the medial meniscus is much larger in diameter, is thinner in its periphery and narrower in body than the lateral meniscus, and does not attach to either cruciate ligament. We evaluated correlations with sites of tear and history of trauma. METHODS AND MATERIALS: We reviewed retrospectively in 43 patients with meniscal tears on MRI(51 cases) and correlated them with history of trauma. RESULTS: The most common site of injury was the posterior horn of the medial meniscus(32/51), but high incidence of lateral meniscal tear compared with previous reports was seen. In the cases which had history of trauma, the posterior horn of medial meniscus was most commonly injured(26/34) and 5 meniscal tears were combined with meniscal tear in the other site. The tear in the anterior horn of the medial meniscus was seen only in a patient which had history of trauma and combined with meniscal tear in the other site. But in the meniscal tears without definite history of trauma, the incidence of meniscal tear was different from the meniscal tear with history of trauma. The incidence of lateral meniscal tear(11/17) was highter than medial meniscal tear and the posterior horn of lateral meniscus was commonly injured. CONCLUSION: We concluded that the medial meniscus was commonly injured, especially posterior horn, but in the cases which had no definite history of trauma, the lateral meniscus was commonly ipjured. An awareness of prevalent site of meniscal injuries may be helpful in the diagnostic interpretation of MR imaging of knee.

Peripheral Arterial Thrombolysis by Modified Pulse-Spray Method

PURPOSE: The purposes of this study were to evaluate the efficacy of thrombolysis and to find optimal dose of urokinase and injection time by modified pulse-spray method with multiside-hole catheter in patients of arterriosclerosis obliterans of lower limbs. MATERIALS AND METHODS: Over a 2 month period, 5 cases of peripheral arterial occlusion of lower limbs were treated with 0.7--1.3 million unit of urokinase by modified pulse spray method. With antegrade puncture at the site of superficial femoral artery, the tip of modified pig tail catheter was initially placed approximately 2cm proximal to the distal end of the clot. The procedure started with the use of initial bolus dose of UK(100,000U) of lacing, and then small pulses of highly concentrated urokinase, which are forcefully sprayed throughout the thrombus at a rate of 20,000U/min. After the initial rapid period of deposition, the concentration of UK was reduced to 4,000U/min for residual thrombus. RESULTS: Complete clot lysis were achieved in 3 of 5 occlusions. Mean duration for completion of lysis was 140 min(40-180min) and initial recanalization of artery required 45min(20-90min). Total required dose of UK was 1,120,000U and mean dose for initial recanalization was 660,000U. No significant complications occurred except distal vasospasm in one case. CONCLUSION: Modified pulse spray method using ultrahigh and high dose urokinase is safe, reguires less time and has cost effectiveness in the management of peripheral arterial thrombolysis. Further study is warranted.

Peripheral Lung Mass Attached to The Pleural Diagnostic Effectiveness of Ultrasonically Guided Biopsy

PURPOSE: To evaluate the usefulness of real-time ultrasound-guided biopsy as an aid in diagnosing pleural attached lung lesions. MATERIALS AND METHODS: Over a 2-year period (March 1992 through February 1994), 52 US-guided diagnostic biopsies were performed in 50 patients with peripheral lung lesions in contact with chest wall. 15 cases were performed with gun biospy and 37 cases with fine needles. Final diagnosis was confirmed by surgery and clinical follow-up. RESULTS: In 44 of 52 cases(84.6%), we obtained histologic or cytologic material by US-guided biopsy. Diagnostic accuracy and tissue type specific accuracy for malignancy were 83.9%(26/31) and 67.7% (21/31), respectively. Eighteen case% were reported to be benign and one of them was proven to be metastatic lesion. We could not find any complications such as hemoptysis or pneumothorax. CONCLUSION: Ultrasound-guided biopsy is a simple, safe and accurate diagnostic procedure for evaluation of peripheral lung lesion attached to the pleura.

Renal cell carcinomas first detected by Tc-MDP bone scan / 대한핵의학회잡지

No abstract available.

The changes of CT number in various organs according to hematocrite level

The computed tomography (CT) number is closely related to hematocrit level according to many of the previous reports. We measured the CT number in various organs, such as the frontal white matter, basal ganglia, occipital white matter, cerebrospinal fluid, liver, abdominal aorta, spleen, kidney, and psoas muscle. We correlated the CT numbers of the organs with hematocrit levels which were graded into 10% increments (20.0-29.9%, 30.0-39.9%, 40.0-49.9%). Thus the change of CT numbers in various organs according to the hematocrit level was analyzed. The increased CT numbers according to the 10% increment of hematocrit in the frontal white matter, basal ganglia, occipital white matter, liver, abdominal aorta, spleen, and psoas muscle were 1.3, 1.5, 1.6, 3.3, 5.3, 3.8, 2.4 respectively. Even though the CT numbers of the cerebrospinal fluid and kidney were not influenced by hematocrit level the CT numbers in most of the there organs postitively correlated with hematocrit level. Therefore, it was concluded that in the differential diagnosis using CT numbers, the hematocrit level of patient must be taken into consideration.

Effects of major blood components on CT number: an experimental study

The study was undertaken to evaluate the effect of major blood components on the CT number. The CT numbers according to the various levels of hematocrit, total protein and cholesterol were checked and analysed by the dilution of pack cell, plasma and 184 complete blood cell count samples under same scanning conditions. In case of normal protein and cholesterol level(33 samples), the CT number was increased about 5.5 hounsfield unit according to 10% increase of hematocrit level: and In case of normal hematocrit and cholesterol level(39 samles), the CT number was increased about 3.5 hounsfield unit according to 1gm% increase of protein level. CT number changes were not predictable according to the changes of cholesterol level(34 samples). From these results, we concluded that major blood components should be considered in the CT number analysis of tissue.

MR findings of paranasal sinus mucocele report of 3 cases

The signal intensity of paranasal sinus mucocele is highly variable, ranging from high to low on both T1 weighted and T2 weighted sequence, This variation is likely due to the combined effects of decreased free water concentration, cross-linking and polymerization of the macromolecular mucus glycoprotein, and increased viscosity. We have experienced three cases of the paranasal sinus mucocele with different signal intensity on Magnetic Resonance Imaging. We describe MR characteristics of the paranasal sinus mucocele and compare with MR characteristics for other paranasal sinus disease.

Reevaluation of the “falx sign”

Visualization of falx cerebri on non-enhanced CT of children with severe head injuries (the falx sign) has been regarded as an evidence of subarachnoid hemorrhage. On the contrary, other authors have reported reverse results. To evaluate clinical significance of the falx sign, authors studied frequency of visualization and CT number of falx cerebri and dural sinuses in 65 children with head injury and 65 children without head injury examined by cranial CT at the Dep. of Radiology, St. Paul's Hospital, Catholic Medical College from March to Sept. 1981. All patients with head trauma were studied within 1 week of the traumatic event. Visualization of falx cerebri was observed at slice in the region of lateral ventricle and slice near to vertex respectively. On the slice in the region of lateral ventricle, falx cerebri was identified in 82% of all of the children examined, of which 92%showed partial visualization of falx cerebri and remaining 8% totally. On the slice near to vertex, falx cerebri was identified in 92% of all the children examined, of which 38% showed partial visualization of falx cerebri and remaining 62% totally. In head trauma group, frequency of visualization of falx cerebri was 78% on the slice in the region of lateral ventricle and 89% on the slice near to vertex; in non-traumatic group, frequency of visualization of falx cerebri was 86% and 94% respectively. The highest numerical value of the falx densities averaged 47 Hounflieds (range, 32-63) in non-traumataic group, averaged 49 Housfields (range, 32-69) in head trauma group. All or a portion of the superior sagittal sinus was visualized in 59% of all of the cases studied, 50% in head trauma group, and 69% in nontraumatic group. The straight sinus was identified in 45% of all of the cases studied, 39% in head trauma group, and 51% in non-traumatic group. In conclusion, there was no distinction between head trauma and non-traumatic group in visualization of falx cerebri and dural sinuses, and we could frequently identify the falx density in normal. Also we could find that frequency for visualization of falx cerebri and drual sinuses increased as the age increased.