Differentiation of Adenomyoma from Localized Adenocarcinoma of the Ampulla of Vater Using Multidetector CT

Purpose@#To determine the multidetector CT (MDCT) findings that differentiate adenomyoma of the ampulla of Vater (AOV) from localized adenocarcinoma of the AOV. @*Materials and Methods@#Sixteen and 30 patients with adenomyoma and localized adenocarcinoma of the AOV, respectively, were evaluated using MDCT. We analyzed the size and attenuation value and presence of uniform enhancement of the lesions, diameters of the extrahepatic bile duct (EHD) and main pancreatic duct, presence of regional lymph node enlargement, and laboratory findings. We determined the independent findings for differentiating adenomyoma from localized adenocarcinoma of the AOV using multivariate analysis. @*Results@#The size of the lesion and diameter of the EHD were significantly smaller for adenomyoma than those for localized adenocarcinoma of the AOV (all p < 0.001). In multivariate analyses, a lesion size of ≤ 1.3 cm, an EHD diameter of ≤ 1.3 cm, and an alanine transaminase level of ≤ 31 IU/L significantly differentiated adenomyoma from localized adenocarcinoma of the AOV. When all of these three findings were met, the specificity for adenomyoma of the AOV was 93.3%. @*Conclusion@#MDCT imaging may facilitate the differential diagnosis of adenomyoma and localized adenocarcinoma of the AOV based on the size of the lesion and diameter of the EHD.

Differentiation of Adenomyoma from Localized Adenocarcinoma of the Ampulla of Vater Using Multidetector CT

Purpose@#To determine the multidetector CT (MDCT) findings that differentiate adenomyoma of the ampulla of Vater (AOV) from localized adenocarcinoma of the AOV. @*Materials and Methods@#Sixteen and 30 patients with adenomyoma and localized adenocarcinoma of the AOV, respectively, were evaluated using MDCT. We analyzed the size and attenuation value and presence of uniform enhancement of the lesions, diameters of the extrahepatic bile duct (EHD) and main pancreatic duct, presence of regional lymph node enlargement, and laboratory findings. We determined the independent findings for differentiating adenomyoma from localized adenocarcinoma of the AOV using multivariate analysis. @*Results@#The size of the lesion and diameter of the EHD were significantly smaller for adenomyoma than those for localized adenocarcinoma of the AOV (all p < 0.001). In multivariate analyses, a lesion size of ≤ 1.3 cm, an EHD diameter of ≤ 1.3 cm, and an alanine transaminase level of ≤ 31 IU/L significantly differentiated adenomyoma from localized adenocarcinoma of the AOV. When all of these three findings were met, the specificity for adenomyoma of the AOV was 93.3%. @*Conclusion@#MDCT imaging may facilitate the differential diagnosis of adenomyoma and localized adenocarcinoma of the AOV based on the size of the lesion and diameter of the EHD.

Successful Endovascular Treatment of an Infected Aortic Aneurysm Induced by Klebsiella pneumoniae

Aortic aneurysms infected by Klebsiella pneumoniae are rarely seen. We describe a 50-year-old man with infected aortic aneurysm that was successfully treated with endovascular aneurysm repair (EVAR). Diagnosis was confirmed using blood culture and computed tomography (CT). Intravenous antibiotics were immediately administered, with improvements in clinical findings and negative blood cultures before the procedure. Twenty-four months after the procedure, the patient was stable and serial CT revealed regression of the infected aortic aneurysm. Therefore, after controlling bacteremia and fever with targeted antibiotic therapy, EVAR can be considered as an alternative for patients who have serious comorbidities and are ineligible for conventional surgery.

Transcatheter Arterial Embolization with N-Butyl Cyanoacrylate for Profunda Femoris Artery Pseudoaneurysms Caused by Femur Shaft Fractures: Two Case Reports

Pseudoaneurysm formation in the profunda femoris artery (PFA) is a rare complication of femur shaft fractures or, more usually, a consequence of operative repair. Over the past few years, percutaneous transcatheter arterial embolization (TAE) has increasingly been considered the most effective treatment for pseudoaneurysms of the PFA. We report two cases with pseudoaneurysms of the PFA that were caused by femur shaft fractures and were successfully treated using TAE with n-butyl cyanoacrylate (NBCA). When a pseudoaneurysm of the PFA occurs due to a femur shaft fracture, early recognition and prompt radiologic intervention may prevent severe vascular injury without the need for additional surgery. The advent of TAE using NBCA enables minimally invasive treatment to be undertaken and it is effective for managing pseudoaneurysms of the PFA.

Primary hepatic peripheral T-cell lymphoma mimicking hepatocellular carcinoma: a case report

Peripheral T-cell lymphomas (PTCLs) are aggressive neoplasms which may involve the liver. The imaging manifestations of hepatic lymphoma are highly variable and show overlapping appearances of numerous other hepatic diseases. As the management and prognosis of lymphoma differ markedly from those of other malignant diseases, prompt diagnosis and early effective treatment are very important. Here, we report an atypical case of primary PTCL not otherwise specified involving the liver that exhibited a solitary hepatic mass mimicking hepatocellular carcinoma (HCC) on CT. Liver biopsy is not commonly recommended in highly suspicious cases of HCC. However, in a patient without risk factors for HCC, consideration of other diagnostic possibilities is required and needle biopsy may be a more rational choice. An imaging approach, based on a careful review of clinical and laboratory findings is essential to prevent false-positive diagnosis of HCC and subsequent invasive treatment.

MR Imaging of Primary Retroperitoneal Mucinous Cystadenocarcinoma in Pregnant Woman

Primary retroperitoneal mucinous cystadenocarcinoma is a very rare malignancy. To date, 51 cases have been reported, including 3 in pregnant women. Herein, we report magnetic resonance findings of a 31-year-old Korean woman (15 weeks and 3 days pregnant) with primary retroperitoneal mucinous cystadenocarcinoma. On abdominal magnetic resonance imaging (MRI), a mass was identified in the retroperitoneal area with a nodular lesion showing heterogeneous signal intensity and focal wall thickening on T1- and T2-weighted images. Exploratory laparotomy and tumor excision were performed. Histological examination revealed primary retroperitoneal mucinous cystadenocarcinoma. The patient subsequently underwent total hysterectomy, bilateral salpingo-oophorectomy, and omentectomy for metastatic mucinous cystadenocarcinoma of both ovaries 15 months after her initial surgery.

Unilateral Hydronephrosis and Hydroureter by Foreign Body in Urinary Bladder: A Case Report

Foreign bodies inserted through the urethra are often found in the urinary bladder. We presently report the first case of hydronephrosis and hydroureter due to direct compression in the urinary bladder by silicon, which had been introduced by the patient himself 2 yr prior to presentation with severe right flank pain. Computed tomography indicated a convoluted, high-attenuation mass in the urinary bladder; unilateral hydronephrosis and hydroureter were also present due to direct compression by the mass. The foreign body was removed using a cystoscope. This foreign body was proven to be silicon.

The Treatment of a Giant Mediastinal Bronchial Artery Aneurysm by Transarterial Coil Embolization: A Case Report

Cases of bronchial artery aneurysms (BAAs) are rare; to the best of our knowledge, only 50 cases have been reported in the literature to date. BAAs require optimal treatment due to the possibility of life-threatening hemorrhaging if the aneurysm was to rupture. BAAs are usually treated by surgical resection of the aneurysmal artery. However, when the patient is unstable due to massive or recurrent hemoptysis, a bronchial artery embolization is a useful alternative treatment method. We report a case of a giant mediastinal bronchial artery aneurysm that was treated by coil embolization.

A Congenital Cystic Adenomatoid Malformation with Intact Pulmonary Vascularities

Congenital cystic adenomatoid malformation (CCAM) is a rare pulmonary disease. It is thought to represent the abnormal proliferation of immature alveoli and other mesenchymal components secondary to abrupt halting of terminal alveolus formation after 16 weeks of gestation. Radiographic parameters such as size, number, and content are variable. On grayscale ultrasound, anechoic, thin-walled cysts are usually noted in pleural or cardiodiaphragmatic locations. To our knowledge, there has been no report of a CCAM showing normal pulmonary vascularities. We report a case of CCAM with normal pulmonary vascularities found within the hypodense lesions on dynamic chest CT.

Complications Following Radiofrequency Ablation of the Porcine Liver through Portal Vein Penetration: Radiological Findings

PURPOSE: To evaluate complications after radiofrequency ablation (RFA) of the porcine liver through portal vein penetration. MATERIALS AND METHODS: Twelve pigs were divided into two groups. In group I (n=11) animals, the portal veins were directly penetrated with an electrode, and in the group II (n=16) animals, the portal veins were located within the expected ablation area. For the group I pigs, RFA were performed for seven minutes after complete portal vein passing of the exposed tip. Gray-scale and Doppler ultrasonography, and CT were performed before and after RFA on the procedure day, and on day two. If any complications were found, the same studies were performed at day seven. We analyzed the presence and extent of thrombotic occlusion, the vascular stricture, the arterioportal shunt, and the presence of an intra-abdominal hemorrhage. We applied Fisher's exact test to compare the complication rate between the two groups;, a value was considered statistically significant if the p-value was less than 0.05. RESULTS: In the group I animals (n=11), three had complete thrombotic occlusion of the portal vein. Among these three animals,, one had a segmental infarction, and one animal showed a partial occlusion. In the group II animals (n=16), complications were not identified. Statistical analysis revealed the complication rate of group I was significantly higher than that of group II (p=.019). CONCLUSION: The portal vein occlusion rate was significantly higher in the portal vein penetrating group than in the non-penetrating group.

Computed Tomographic Appearance of the Anterior Diaphragm: Evaluation with 64-slice MDCT

PURPOSE: To re-evaluate the appearance of the anterior diaphragm by the use of MDCT. MATERIALS AND METHODS: We performed a retrospective review of 81 consecutive patients that underwent chest CT by using 64 channel MDCT. We classified the anterior diaphragm as three types (types 1-3) based on 5 mm axial scans: a line behind the xiphoid, a discontinuity and opening anteriorly, and the presence of broad and poorly defined bands. We also classified the anterior diaphragm as three types (types A-C) using 2 mm sagittal reformation images, based on the shape of the anterior diaphragmatic fibers traveling from the base of the pericardium to the xiphoid: a downward slope, an upward slope, and a flat shape, and compared the two groups using a correlation determined by statistical analysis. RESULTS: We could classify the appearance of the anterior diaphragm for all cases on the axial scans and sagittal reformation images. The number of types 1, 2, 3 on the axial scans was 30.9%, 38.3%, and 30.9% and the number of types A, B, C on the sagittal reformation images was 33.3%, 22.2%, and 44.4%, respectively. Type A was seen for 92% of type 1 cases, type C was seen for 88% of type 3 cases, and type B was seen for 54.8% of type 2 cases. The types seen between the axial and sagittal reformation images showed a significant agreement (r=0.868, p < 0.01). CONCLUSION: The shape of the anterior diaphragm correlated with the relationship between the base of the pericardium and the xiphoid.

Hidradenitis Suppurativa Presenting with a Posterior Neck Mass: A Case Report

Hidradenitis suppurativa is a rare disorder that is characterized by recurrent chronic skin infections and the formation of sinus tracts and considerable scaring. A 37-year-old man presented with a hard posterior neck mass. Multiple pus-producing sinuses were detected in the skin covering the mass. MRI demonstrated an ill-defined, soft tissue mass with multiple variable sized cystic lesions. The soft tissue mass measured 12x10x4 cm in the subcutaneous fat layer, it contained multifocal cystic lesions that revealed higher signal intensity on both the T1- and T2-weighted images, as compared with the adjacent neck muscles. The mass was not enhanced on the post-contrast T1 weighted images. Some of the cystic lesions extended to the skin. The mass was removed surgically and confirmed to be hidradenitis suppurativa.

A Case of Simple Type Caroli's Disease Confined to Right Lobe of the Liver / 대한소화기학회지

Caroli's disease is a rare congenital hepatobiliary disease characterized by multifocal segmental dilatation of intrahepatic bile ducts affecting all or parts of the liver. Two forms of Caroli's disease are described, the pure form and that associated with periportal fibrosis. The disease may diffusely affect the liver or be localized to one lobe or segment. Less than 20% of all reported cases of Caroli's disease are monolobar type. We report a case of simple type Caroli's disease confined to right lobe of the liver in a 22 year old man. He was admitted due to right upper abdominal pain and diagnosed by magnetic resonance cholangiopancreatography. He was treated with right hepatic lobectomy and recovered completely.

Differentiation of Benign and Malignant Thyroid Nodules: Sonographic Analysis and a New Scoring System

PURPOSE: To analyze the synthetically created sonographic features of thyroid nodules, we present here a new scoring system for the sonographic features that are suggestive of malignant thyroid nodules. We also evaluated the accuracy and clinical significance of this system. MATERIALS AND METHODS: In this study, we included 725 thyroid nodules of 405 patients that were pathologically proven by USG-guided percutaneous fine-needle aspiration biopsy (FNAB) or surgery. Two radiologists analyzed the sonographic features according to the internal content, margin, echogenecity, shape and calcification. We scored from 0 point to 2 point for each feature, and then we calculated the total scores and classified them as three groups according to the total score such as low risk (0-3), intermediate risk (4-6) or high risk (7-10). We demonstrated the difference of the frequency and the positive predictive value among the three groups by using the Chi-square test (p<0.005). RESULTS: For 725 nodules, 654 (90.2%) were benign and 71 (9.8%) were malignant. For 589 nodules classified as low risk, 10 (1.7%) were malignant. For 102 nodules classified as intermediate risk, 32 (31.4%) were malignant. For 34 nodules classified as high risk, 29 (85.8%) were malignant. There was a statistically significant difference in the frequency and positive predictive value of malignancy among the three groups (p<0.001). CONCLUSION: There was a statistically significant difference in the frequency and positive predictive value of malignancy among the three groups for the new scoring system presented in this study to analyze the synthetically sonographic features of thyroid nodules. So, we think that sonography can be helpful for making the differentiation between benign and malignant nodules. When we find thyroid nodules on sonography, we can reduce the unnecessary FNAB and we can diagnose malignant nodules at an earlier stage.

A Case of Rectal Gastrointestinal Stromal Tumor (GIST) Presenting with Hematochezia / 대한소화기내시경학회지

Gastrointestinal stromal tumors (GIST) are the most common mesenchymal neoplasms affecting the gastrointestinal tract. The main sites for GIST are the stomach and small intestine but they can also occur in the rectum, albeit rarely. We report a 58-year-old woman who presented with hematochezia. Endoscopically, a submucosal tumor with mucosal ulceration was located approximately 2 cm from the anal verge. The pelvic CT and MRI scanning findings demonstrated a large low-density lesion with intraluminal growth from the lower rectum and an absence of tumor infiltrations to other organs. The patient underwent an abdominoperineal resection of the rectum. A histopathological examination showed fascicular proliferation of spindle shaped cells. The mitotic rate was more than 30 mitotic figures per 50 high-power fields. A immunohistochemical examination revealed most of the tumor cells to be positive for the c-kit protein, CD34 and SMA (alpha-smooth muscle action). The tumor was diagnosed as a GIST of the rectum.

A Case of Primary Pancreatic T-cell Lymphoma

Primary pancreatic lymphoma is a rare extranodal manifestation of any histopathologic subtype of non-Hodgkin's lymphoma that predominantly involves the pancreas, and it comprises less than 0.5% of all pancreatic malignancies. Histopathologically, most primary pancreatic lymphomas are the B-cell phenotypes, and T-cell lymphomas are extremely rare. We describe here the ultrasonography and computed tomography (CT) findings of a pathologically confirmed pancreatic T-cell lymphoma in a 37-year-old female patient. Ultrasonography showed diffuse pancreatic enlargement and a slightly bulging mass in the head and tail of pancreas that had markedly heterogeneous echogeneity. The lesion abutted onto the adjacent vessels, but there was no evidence of luminal narrowing or obstruction. The CT scan showed diffuse enlargement of the pancreas and the bulging contoured mass at the pancreatic head and tail with inhomogeneous enhancement, including multiple hypodense areas. It also showed the patent peripancreatic vessels and multiple LN enlargements around the pancreas.

A Case of Primary Pancreatic T-cell Lymphoma

Primary pancreatic lymphoma is a rare extranodal manifestation of any histopathologic subtype of non-Hodgkin's lymphoma that predominantly involves the pancreas, and it comprises less than 0.5% of all pancreatic malignancies. Histopathologically, most primary pancreatic lymphomas are the B-cell phenotypes, and T-cell lymphomas are extremely rare. We describe here the ultrasonography and computed tomography (CT) findings of a pathologically confirmed pancreatic T-cell lymphoma in a 37-year-old female patient. Ultrasonography showed diffuse pancreatic enlargement and a slightly bulging mass in the head and tail of pancreas that had markedly heterogeneous echogeneity. The lesion abutted onto the adjacent vessels, but there was no evidence of luminal narrowing or obstruction. The CT scan showed diffuse enlargement of the pancreas and the bulging contoured mass at the pancreatic head and tail with inhomogeneous enhancement, including multiple hypodense areas. It also showed the patent peripancreatic vessels and multiple LN enlargements around the pancreas.

Anatomic Landmarks of Fluoroscopy Guided Puncture of the Pulseless Femoral Artery

PURPOSE: We wanted to improve puncturing the pulseless femoral artery by evaluating the anatomic landmarks that suggest the course of the femoral artery on fluoroscopy. MATERIALS AND METHODS: We analyzed 37 hemipelvis spot images that were centered on the arterial sheath after puncture of the femoral artery. The inguinal angles were measured between the inguinal line connecting the anterior superior iliac spine and the symphysis pubis, and the line of the arterial sheath. Inguinal ligament ratios were measured as the distance from the symphysis pubis to the arterial sheath to the length of the inguinal ligament on the inguinal line. The femoral head ratios were measured as the distance from the medial margin of the femur head to the arterial sheath to the transverse length of the femur head. RESULTS: The mean inguinal angle was 66.5degree (+/-7.8degree) and the mean inguinal ligament ratio was 0.42 (+/-0.03). The mean femoral head ratio was 0.08 (+/-0.18). In comparing the men and women, there was no significant difference in the inguinal angle and the femoral head ratio, but the inguinal distance ratio was larger in women (men: 0.41+/-0.033, women: 0.44+/-0.031, p < 0.05). CONCLUSION: The femoral artery generally courses just lateral to the medial margin of the femur head (femoral head ratio: 0.08) and the medial 40% of the inguinal ligament (inguinal ligament ratio: 0.42). So, consideration of these relations may be helpful for puncturing the pulseless femoral artery.

Ultrasound-Guided Fine-Needle Aspiration Biopsy of Multiple Thyroid Nodules

PURPOSE: To standardize the number of nodules which necessitates ultrasound-guided, fine-needle, aspiration biopsy in patients who have multiple thyroid nodules with the same sonographic characteristics as each other. MATERIALS and METHODS: From February, 2002 to March, 2004, among patients whose diagnosis was confirmed by ultrasound-guided, fine-needle, aspiration biopsy, 545 nodules of 203 patients were found in sonography with more than two thyroid nodules. Each thyroid gland nodule was classified on a score from 0 to 2 points on the basis of the following 5 characteristics: internal content, margin, echogenicity, shape and calcification in sonography. When the score of all characteristics was the same, by deciding on nodules with the same sonographic char-acteristics and with the score of at least one characteristic being different, we divided the nodules with different sonographic characteristics in a patient. By methods such as given in the preceding descriptions, patients with multiple thyroid nodules were separated into two groups: one in which all nodules had the same sonographic characteristics and another in which nodules have at least one different sonographic characteristic. Then, each pathologic result was searched for the same case and different case in each patient group. RESULTS: Among the 203 patients who were diagnosed with multiple thyroid nodules in ultrasonography, 79 patients (38.9%) had nodules with the same ultrasonographic characteristics and 124 patients (61.1%) had nodules with at least one different ultrasonographic characteristic. All 79 patients' nodules with the same ultrasono-graphic characteristics in each patient showed the same pathologic result in all cases (100.0%) and there was no case showing a different pathologic result. Otherwise, among the 124 patients' nodules with different ultrasono-graphic characteristics, each patient showed the same pathologic result in 111 (89.5%) and different pathologic result in 13 (10.5%). CONCLUSION: In patients who have multiple thyroid nodules, if a patient's nodules have the same sonographic characteristics, we can perform ultrasound-guided, fine-needle, aspiration biopsy about only one nodule and if a patient's nodules have different sonographic characteristics from each other, we must perform the biopsy for all nodules.

A Middle Cerebral Artery Occlusion Model in Rabbits: Development with Endovascular Interventional Techniques and Evaluation by Magnetic Resonance Imaging

PURPOSE: The aim of this study was to develop a new middle cerebral artery occlusion (MCAO) model in rabbits using a less invasive, endovascular interventional technique. The new animal model's technical feasibility and its success in producing lesions was evaluated using magnetic resonance imaging (MRI). MATERIALS AND METHODS: Ten rabbits were used to develop the MCAO models using a transfemoral catheter-based technique. After catheterization of the common carotid artery, a microcatheter was introduced coaxially through the catheter to cannulate the internal carotid artery and to embolize the MCA with polyvinyl alcohol particles. We evaluated how successful we were in selecting the vessels, catheterization, embolization, and also evaluated how many of the animals survived until the end of experiment. Diffusion-weighted imaging (DWI) and T2-weighted imaging (T2WI) were performed in one-hour intervals to monitor the ischemic lesion for a total of six hours following successful occlusion of the target artery. The relative volume of the lesion was calculated as a hemispheric lesion volume (HLV, %). The signals of the lesion and contralateral normal brain (control) were measured in each image at every time point. Lesion-to-control signal-intensity ratio (SIR) of DWI, and T2WI were obtained together with relative apparent diffusion coefficient (rADC). RESULTS: Catheterization and embolization of the internal carotid artery were successful in all 10 rabbits, which showed relevant lesions on MRI. All rabbits survived until the end of the experiment. The HLV (mean+/-standard deviation) was 35.7+/-14.6%. The relative ADC was 0.80+/-0.13. The lesion signals on DWI and T2WI showed a gradual increase as time passed, while the ADC value of the lesion gradually decreased (p<0.0001). CONCLUSION: The rabbit MCAO model using an endovascular interventional technique is technically feasible, and provides a reproducible lesion in the target arterial territory. MRI successfully revealed a typical finding of acute cerebral infarction. This model is also believed to be suitable for the MRI investigation of acute cerebral ischemia.