Current and Future Clinical Applications of High-Intensity Focused Ultrasound (HIFU) for Pancreatic Cancer

High-intensity focused ultrasound (HIFU) is a novel therapeutic modality that permits noninvasive treatment of various benign and malignant solid tumors, including prostatic cancer, uterine fibroids, hepatic tumors, renal tumors, breast cancers, and pancreatic cancers. Several preclinical and clinical studies have investigated the safety and efficacy of HIFU for treating solid tumors, including pancreatic cancer. The results of nonrandomized studies of HIFU therapy in patients with pancreatic cancer have suggested that HIFU treatment can effectively alleviate cancer-related pain without any significant complications. This noninvasive method of delivering ultrasound energy into the body has recently been evolving from a method for purely thermal ablation to harnessing the mechanical effects of HIFU to induce a systemic immune response and to enhance targeted drug delivery. This review provides a brief overview of HIFU, describes current clinical applications of HIFU for pancreatic cancer, and discusses future applications and challenges.

Arterivenous Fistula Complicated by Popliteal Venous Access for Endovascular Thrombolytic Therapy of Deep Vein Thrombosis

We report a case of an iatrogenic arteriovenous fistula complicated by catheter-directed thrombolytic therapy in a patient with acute deep vein thrombosis of a lower extremity. To the best of our knowledge, this is the first report of an arteriovenous fistula between the sural artery and popliteal vein in that situation. As the vessels have a close anatomical relationship, the arteriovenous fistula seems to be a potential complication after endovascular thrombolytic therapy of acute deep vein thrombosis.

Evaluation of Deep Vein Thrombosis with Multidetector Row CT after Orthopedic Arthroplasty: a Prospective Study for Comparison with Doppler Sonography

OBJECTIVE: This prospective study evaluated the ability of indirect 16-row multidetector CT venography, in comparison with Doppler sonography, to detect deep vein thrombosis after total hip or knee replacement. MATERIALS AND METHODS: Sixty-two patients had undergone orthopedic replacement surgery on a total of 30 hip joints and 54 knee joints. The CT venography (scan delay time: 180 seconds; slice thickness/increment: 2/1.5 mm) and Doppler sonography were performed 8 to 40 days after surgery. We measured the z-axis length of the beam hardening artifact that degraded the image quality so that the presence of deep vein thrombosis couldn't be evaluated on the axial CT images. The incidence and location of deep vein thrombosis was analyzed. The diagnostic performance of the CT venograms was evaluated and compared with that of Doppler sonography as a standard of reference. RESULTS: The z-axis length (mean +/- standard deviation) of the beam hardening artifact was 4.5 +/- 0.8 cm in the arthroplastic knees and 3.9 +/- 2.9 cm in the arthroplastic hips. Deep vein thrombosis (DVT) was found in the popliteal or calf veins on Doppler sonography in 30 (48%) of the 62 patients. The CT venography has a sensitivity, specificity, positive predictive value, negative predictive value and accuracy of 90%, 97%, 96%, 91% and 94%, respectively. CONCLUSION: The ability of CT venography to detect DVT was comparable to that of Doppler sonography despite of beam hardening artifact. Therefore, CT venography is feasible to use as an alternative modality for evaluating post-arthroplasty patients.

Lipoblastoma of Mediastinum: A case report / 대한흉부외과학회지

Lipoblastoma is a rare benign tumor that usually originates in children from the embryonic lipid cells of the extremities. This condition shows an early childhood occurrence, a benign nature without metastasis, a cellular composition of mainly mature lipid cells and an ability to differentiate into a simple lipoma. We have experienced a 15 month old girl who had developed a lipoblastoma in the right anterior mediastinum. Surgical resection was carried out without complications. Her postoperative course was uneventful. She has been well 6 months after the operation.

Pleomorphic Hyalinizing Angiectatic Tumor of the Chest Wall: A case report / 대한흉부외과학회지

Pleomorphic hyalinizing angiectatic tumor (PHAT) is a rare, low grade soft tissue neoplasm of an unknown histogenesis. It is characterized by sheets of mitotically inactive oval and pleomorphic cells, mono- and multi-nucleated giant cells, intranuclear cytoplasmic inclusions and prominent clusters of thin-walled ectatic vessels with perivascular hyalinization. We have experienced a 50 years old male patient who had a palpable mass in his right anterior lower chest wall. The mass was excised and it was confirmed as PHAT. He has been well 2 years postoperatively without recurrence.

MR Imaging in a Child with Scurvy: a Case Report

Scurvy is very rare disease in industrialized societies. Nevertheless, it still exists in higher risk groups including economically disadvantaged populations with poor nutrition, such as the elderly and chronic alcoholics. The incidence of scurvy in the pediatric population is very low. This study reports a case of scurvy in a 5-year-old girl with cerebral palsy and developmental delay based on MRI findings.

MR Imaging of Mucinous Carcinoma of the Breast Associated with Ductal Carcinoma In Situ: Case Report

A mucinous carcinoma of the breast is an uncommon carcinoma containing mucin that is associated with a mucocele-like tumor or other malignant tumors. We report the MR imagingfindings of two cases, a mucinous carcinoma and ductal carcinoma in situ (DCIS), associated with mucocele-like tumor. The mucinous carcinoma showed a gradually enhancing kinetic pattern on the dynamic MR and high signal intensity on the T2-weighted images. The MR findings were indistinguishable from a common benign mass of the breast.

MR Imaging of Mucinous Carcinoma of the Breast Associated with Ductal Carcinoma In Situ: Case Report

A mucinous carcinoma of the breast is an uncommon carcinoma containing mucin that is associated with a mucocele-like tumor or other malignant tumors. We report the MR imagingfindings of two cases, a mucinous carcinoma and ductal carcinoma in situ (DCIS), associated with mucocele-like tumor. The mucinous carcinoma showed a gradually enhancing kinetic pattern on the dynamic MR and high signal intensity on the T2-weighted images. The MR findings were indistinguishable from a common benign mass of the breast.

MR Findings of Synovial Sarcoma with Intraosseous Involvement: Case Report

Synovial sarcoma is rare soft tissue tumor mesenchymal origin. Osseous involvement of synovial sarco-ma is rare. A 24-year-old man presented with pain and swelling of the lower extremity. MRI of the lower extremity demonstrated a large mass encircling tibia with osseous involvement. Surgical excision of the mass was done and the mass was diagnosed as biphasic synovial sarcoma with bone marrow involvement. We also discuss the other imaging findings of synovial sarcoma on MRI.

Rectal Teratoma coexistent with an Ovarian Teratoma: A Case Report

We report a case of rectal teratoma coexistent with an ovarian teratoma. To our knowledge, this is the first radiologic report of rectal teratoma. Computed tomography (CT) showed a sharply demarcated cystic and fatty mass with amorphous calcification in the rectum. A double-contrast barium study showed a well-defined intraluminal rectal mass without mucosal destruction. Imaging findings of rectal teratoma allow for correct preoperative diagnosis. CT was helpful in differentiating rectal teratoma from other rectal lesions.

A Case of Prader-Willi Syndrome with Bilateral Hutch Diverticula Associated with Vesicoureteral Reflux

Our patient is the first reported case of Prader-Willi syndrome(PWS) with bilateral Hutch's diverticula. We believe that hypotonia in PWS is associated with multiple bladder diverticula and vesicoureteral reflux. We conclude that PWS can be considered a possible associated syndrome in patients with multiple bladder diverticula.

Usefulness of Helical CT in the Diagnosis of Strangulation in Small Bowel Obstruction

PURPOSE: We wished to evaluate the usefulness of helical CT for the diagnosis of strangulation of the dilated small bowels. MATERIALS AND METHODS: The CT scans of 31 patients with small bowel obstruction from various causes were reviewed retrospectively. Thirteen of these patients were confirmed as small bowel strangulation by surgery and pathology. Fourteen patients underwent surgery, but they had no strangulation. Three patients were reduced by using a nasogastric tube and one infant with intussusception was reduced by air reduction. The following CT findings of strangulation were evaluated: reduced bowel wall enhancement by visual assessment and measuring the HU, ascites, thickening of bowel wall, abnormal mesenteric vessel location and whirlpool appearance, and mesenteric venous engorgement. For the precise evaluation of reduced bowel wall enhancement, the HUs were measured by 1 mm2 of ROI, and the differences of HUs between the well enhanced bowel and poorly enhanced bowel were compared. RESULTS: For the diagnosis of strangulation, measurement of HU of the bowel wall could improve the sensitivity from 69% to 100%. The specificity of both methods, by visual assessment and measurement of HU, was 94%. Ascites had a sensitivity of 69% and specificity of 44%. Thickening of bowel wall had a sensitivity of 38% and specificity of 78%. Abnormal mesenteric vessel location and whirlpool appearance had a sensitivity of 38% and specificity of 83%. Mesenteric venous engorgement had a sensitivity of 31% and specificity of 72%. CONCLUSION:Measurement of HU of the bowel wall after contrast enhancement can be a useful method in the differential diagnosis between the strangulated and non-strangulated bowels in patients with small bowel obstruction.

Differentiation of Recurrent Rectal Cancer and Postoperative Fibrosis: Preliminary Report by Proton MR Spectroscopy

PURPOSE: To know the differences of proton MR spectroscopic features between recurrent rectal cancer and fibrosis in post-operative period, and to evaluate the possibility to discriminate recurrent rectal cancer from post-operative fibrosis by analysis of proton MR spectra. MATERIALS AND METHODS: We evaluated the proton MR spectra from 25 soft tissue masses in perirectal area that developed in post-operative period after operation for the resection of rectal cancer. Our series included 11 cases of recurrent rectal cancer and 14 of fibrotic mass. All cases of recurrent rectal cancer and post-operative fibrosis were confirmed by biopsy. We evaluated the spectra with an attention to the differences of pattern of the curves between recurrent rectal cancer and post-operative fibrosis. The ratio of peak area of all peaks at 1.6 -4.1ppm to lipid (0.9 - 1.6ppm) [P (1.6 -4.1ppm)/P (0.9 -1.6ppm)] was calculated in recurrent rectal cancer and post-operative fibrosis groups, and compared the results between these groups. We also evaluated the sensitivity and specificity for discriminating recurrent rectal cancer from post-operative fibrosis by analysis of 1 H-MRS. RESULTS: Proton MR spectra of post-operative fibrosis showed significantly diminished amount of lipids compared with that of recurrent rectal cancer. The ratio of P (1.6 -4.1ppm)/P (0.9 -1.6ppm) in post-operative fibrosis was much higher than that of recurrent rectal cancer with statistical significance (p < .05) due to decreased peak area of lipids. Mean (standard deviations of P (1.6 -4.1ppm)/P (0.9 -1.6ppm) in post-operative fibrosis and recurrent rectal cancer group were 2.71 +/-1.48 and 0.29 +/- 0.11, respectively. With a cut-off value of 0.6 for discriminating recurrent rectal cancer from post-operative fibrosis, both the sensitivity and specificity were 100% (11/11, and 14/14). CONCLUSION: Recurrent rectal cancer and post-operative fibrosis can be distinguished from each other by analysis of proton MR spectroscopic features, and 1 H-MRS can be a new method for differential diagnosis between recurrent rectal cancer and post-operative fibrosis.

CT Findings of Primary Torsion of the Greater Omentum with Segmental Infarction: Case Report

Herein, we report on a case of primary torsion of the greater omentum with segmental infarction, which should provide useful information for the preoperative diagnosis of future such cases. Primary torsion of the greater omentum with omental infarction is a rare condition. There are only a few radiological reports of secondary torsion of the greater omentum caused by the hernial sac. During surgical exploration, infarction of the greater omentum was identified, due to the observation of omental torsion without any underlying cause. We describe a patient with characteristic computed tomography (CT) findings of primary omental torsion with segmental infarction, which correlated with the operative and pathologic results.

A Clinical Analysis of Surgery in the Elderly Patients with Acute Abdomen

PURPOSE: In surgical treatment for the elderly patients with the acute abdomen, the high morbidity and mortality rate become a serious problem because of the difficulty of the initial diagnosis. This study, therefore, aims at analyzing the clinical presentation of the elderly patients with the acute abdomen in order to reduce the high mortality rate for the elderly patients. METHODS: This study included 114 elderly patients who underwent the emergency operation due to the acute abdomen from May 2000 to May 2002. The age of the elderly patients was over 65 years old. The clinical characteristics of these patients were investigated retrospectively in this study. RESULTS: The most two common diseases were the acute appendicitis(25.4%) and the acute cholecystitis (21.9%) for the elderly patients. Then comes the intestinal obstruction, the gastrointestinal cancer, the colonic diverticulitis, and the gastrointestinal vascular disease in that order. The accuracy of the initial diagnosis was 79%, but the correlation between the accuracy and age significantly decreased as the age of the elderly patients increased. The postoperative complication rate was 26.3%, and the most common cause of the complications was the postoperative infection. The postoperative mortality rate was 11.4%, and the common causes of the death were the sepsis(61.5%), the postoperative bleeding, the acute renal failure, and the cardiovascular disease in order of frequency. It was found that there was a significant correlation between the complication rate and old age(p=0.021). In addition, there was a significant correla- tion between the mortality rate and old age p=0.012). CONCLUSION: In this study, it was found that the acute appendicitis and the cholecystitis were the common diseases for the elderly patients with the acute abdomen. The accuracy of the initial diagnosis was 79%; however, it decreased with the aging process. For aged people, that caused the increase of the complication and the mortality rate. It thus appears that elderly patients with the acute abdomen should be treated carefully and systematically.

A Clinical Analysis of Surgery in the Elderly Patients with Acute Abdomen

PURPOSE: In surgical treatment for the elderly patients with the acute abdomen, the high morbidity and mortality rate become a serious problem because of the difficulty of the initial diagnosis. This study, therefore, aims at analyzing the clinical presentation of the elderly patients with the acute abdomen in order to reduce the high mortality rate for the elderly patients. METHODS: This study included 114 elderly patients who underwent the emergency operation due to the acute abdomen from May 2000 to May 2002. The age of the elderly patients was over 65 years old. The clinical characteristics of these patients were investigated retrospectively in this study. RESULTS: The most two common diseases were the acute appendicitis(25.4%) and the acute cholecystitis (21.9%) for the elderly patients. Then comes the intestinal obstruction, the gastrointestinal cancer, the colonic diverticulitis, and the gastrointestinal vascular disease in that order. The accuracy of the initial diagnosis was 79%, but the correlation between the accuracy and age significantly decreased as the age of the elderly patients increased. The postoperative complication rate was 26.3%, and the most common cause of the complications was the postoperative infection. The postoperative mortality rate was 11.4%, and the common causes of the death were the sepsis(61.5%), the postoperative bleeding, the acute renal failure, and the cardiovascular disease in order of frequency. It was found that there was a significant correlation between the complication rate and old age(p=0.021). In addition, there was a significant correla- tion between the mortality rate and old age p=0.012). CONCLUSION: In this study, it was found that the acute appendicitis and the cholecystitis were the common diseases for the elderly patients with the acute abdomen. The accuracy of the initial diagnosis was 79%; however, it decreased with the aging process. For aged people, that caused the increase of the complication and the mortality rate. It thus appears that elderly patients with the acute abdomen should be treated carefully and systematically.

Postnatal Development of the Atlas and Axis: CT Study

PURPOSE: To evaluate normal postnatal development of the atlas and axis by means of CT scanning. MATERIALS AND METHODS: We prospectively analyzed CT scans of the developing atlas and axis of 200 normal children aged less than 14, investigating the CT appearance of these regions with particular attention to two synchondroses related to the atlas and four synchondroses and one ossification center related to the axis. Fusion varying was categorized as either low (grade1-5) or high (grade4-5), according to the varying degrees of fusion at each synchondrosis or ossification center. RESULTS: Neurocentral synchondrosis of the atlas was low grade in all children less than five, and high grade in all aged nine or more, while posterior synchonrosis of the atlas was low grade in 97% of children less than three and high grade in 99% aged three or more. As for the axis, neurocentral synchondrosis was low grade in all children less than three, and high grade in 97% of children aged five or more. PS of the axis was low grade in both children less than 6 months, and high grade in all aged two years or more. Dentocentral synchondrosis of the axis was low grade in 93% of children less than three and high grade in 96% of those aged at least five. Intradental axial synchondrosis was high grade in all children. Fusion of the terminal ossicle with the remainder of the dens was low in all children less than five and high in 97% of those aged nine or more. CONCLUSION: CT can help determine the parameters of normal postnatal development of the atlas and axis. A knowledge of normal ossification patterns of these regions may help provide an understanding of developmental anomalies and also help prevent confusion with fractures.

The Usefulness of MR Imaging of the Temporal Bone in the Evaluation of Patients with Facial and Audiovestibular Dysfunction

OBJECTIVE: To evaluate the clinical utility of MR imaging of the temporal bone in patients with facial and audiovestibular dysfunction with particular emphasis on the importance of contrast enhancement. MATERIALS AND METHODS: We retrospectively reviewed the MR images of 179 patients [72 men, 107 women; average age, 44 (range, 1-77) years] who presented with peripheral facial palsy (n=15), audiometrically proven sensorineural hearing loss (n=104), vertigo (n=109), or tinnitus (n=92). Positive MR imaging findings possibly responsible for the patients' clinical manifestations were categorized according to the anatomic sites and presumed etiologies of the lesions. We also assessed the utility of contrast-enhanced MR imaging by analyzing its contribution to the demonstration of lesions which would otherwise not have been apparent. All MR images were interpreted by two neuroradiologists, who reached their conclusions by consensus. RESULTS: MR images demonstrated positive findings, thought to account for the presenting symptoms, in 78 (44%) of 179 patients, including 15 (100%) of 15 with peripheral facial palsy, 43 (41%) of 104 with sensorineural hearing loss, 40 (37%) of 109 with vertigo, and 39 (42%) of 92 with tinnitus. Thirty (38%) of those 78 patients had lesions that could be confidently recognized only at contrastenhanced MR imaging. CONCLUSION: Even though its use led to positive findings in less than half of these patients, MR imaging of the temporal bone is a useful diagnostic procedure in the evaluation of those with facial and audiovestibular dysfunction. Because it was only at contrast-enhanced MR imaging that a significant number of patients showed positive imaging findings which explained their clinical manifestations, the use of contrast material is highly recommended.

Usefulness of Dynamic Gadolinium-enhanced MR Imaging in Staging of Bladder Cancer

PURPOSE: To evaluate the usefulness of dynamic gadolinium-enhanced MR imaging in the staging of bladder cancer. MATERIALS AND METHODS: Twenty-four patients with histologically proven bladder cancer underwent MR imaging before tumor resection. Pre contrast axial or sagittal T1- and T2-weighted images were obtained in all patients. In 12, dynamic MR imaging was performed using the 3D-EFGRE technique in the axial plane. Images were obtained 30, 90, and 180 sec after a rapid hand injection of Gd-DTPA. T1W1, T2W1, and Gd-enhanced dynamic images were compared on the basis of lesion conspicuity and correlated with histologic specimens. The signal intensity ratio (SIR) of bladder tumors, muscle, and perivesical fat during each phase, and the contrast-to-noise ratio (CNR) of lesion-to-muscle and lesion-to-fat were determined. RESULTS: The accuracy of tumor staging using both T1WI and T2WI was 38% (9/24), and the accuracy of dynamic gadolinium enhanced MR imaging was 58% (7/12). The difference was statistically significant (p<0.05). The SIR of tumors was highest during the capillary phase, and decreased during the venous phase. During all phases i t was significantl y higher than that of bladder muscle and perivesi cal fat ( P < 0.05). The CNR of tumor-to-muscle and tumor-to-perivesical fat increased abruptly during the arterial phase, was highest during the capillary phase and decreased slightly during the venous phase. CONCLUSION: Dynamic gadolinium enhanced MR imaging improves the diagnostic accuracy of both T1WI and T2WI in the preoperative staging of bladder cancer and can be useful in the management and estimation of prognosis. For evalvation of the staging of bladder cancer, the capillary phase is optimal.

Usefulness of Dynamic Gadolinium-enhanced MR Imaging in Staging of Bladder Cancer

PURPOSE: To evaluate the usefulness of dynamic gadolinium-enhanced MR imaging in the staging of bladder cancer. MATERIALS AND METHODS: Twenty-four patients with histologically proven bladder cancer underwent MR imaging before tumor resection. Pre contrast axial or sagittal T1- and T2-weighted images were obtained in all patients. In 12, dynamic MR imaging was performed using the 3D-EFGRE technique in the axial plane. Images were obtained 30, 90, and 180 sec after a rapid hand injection of Gd-DTPA. T1W1, T2W1, and Gd-enhanced dynamic images were compared on the basis of lesion conspicuity and correlated with histologic specimens. The signal intensity ratio (SIR) of bladder tumors, muscle, and perivesical fat during each phase, and the contrast-to-noise ratio (CNR) of lesion-to-muscle and lesion-to-fat were determined. RESULTS: The accuracy of tumor staging using both T1WI and T2WI was 38% (9/24), and the accuracy of dynamic gadolinium enhanced MR imaging was 58% (7/12). The difference was statistically significant (p<0.05). The SIR of tumors was highest during the capillary phase, and decreased during the venous phase. During all phases i t was significantl y higher than that of bladder muscle and perivesi cal fat ( P < 0.05). The CNR of tumor-to-muscle and tumor-to-perivesical fat increased abruptly during the arterial phase, was highest during the capillary phase and decreased slightly during the venous phase. CONCLUSION: Dynamic gadolinium enhanced MR imaging improves the diagnostic accuracy of both T1WI and T2WI in the preoperative staging of bladder cancer and can be useful in the management and estimation of prognosis. For evalvation of the staging of bladder cancer, the capillary phase is optimal.