Autoimmune pancreatitis is a rare form of chronic pancreatitis characterized by focal or diffuse swelling of the pancreas, irregular narrowing of the main pancreatic duct, hyperglobulinemia, presence of autoantibodies, and marked response to corticosteroid therapy. Patients with autoimmune pancreatitis often have dilatation of the common bile duct without dilatation of the main pancreatic duct. Contrast-enhanced harmonic gray-scale ultrasound has recently been used to evaluate the vascularity of pancreatic mass lesions; it can visualize blood perfusion in pancreatic mass lesions without producing motion artifacts. Patients with pancreatic carcinoma and autoimmune pancreatitis were required to hold their breath from 20 to 50 seconds after administration of Levovist^® (Schering AG, Berlin, Germany) or Sonazoid^® (GE Healthcare, Oslo, Norway) while the vascularity (tumor vessels and tumor enhancement) of the lesion was examined by contrast-enhanced harmonic gray-scale ultrasound (early phase). Lesion enhancement was monitored for about 90 to 180 seconds after the injection with patients holding their breath for several seconds (delayed phase). Although pancreatic carcinoma lesions exhibited some grade of tumor vessels, autoimmune pancreatic lesions showed no apparent tumor vessels in the early phase. Almost all pancreatic carcinoma lesions showed positive enhancement only in the peripheral tumor region; however, autoimmune pancreatitis lesions exhibited enhancement throughout the entire lesion in both the early and delayed phases. Grade of lesion vascularity in the contrast-enhanced harmonic gray-scale ultrasonograms correlated directly with pathologic grade of inflammation and inversely with grade of fibrosis associated with autoimmune pancreatitis lesions. Lesion vascularity had decreased on contrast-enhanced harmonic gray-scale ultrasonograms after steroid therapy. Contrast-enhanced harmonic gray-scale ultrasound was useful in evaluating vascularity of autoimmune pancreatitis lesion and may prove useful in the differential diagnosis between pancreatic carcinoma and autoimmune pancreatitis.

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We explain basic imaging methods and important points concerning transabdominal ultrasonography in patients with pancreaticobiliary diseases. When imaging the intrahepatic bile duct, it is important to recognize that it is adjacent to the portal vein in Glisson′s capsule. Distinguishing between the portal vein and the bile duct is simplified with the use of Doppler ultrasound. It is essential to note dilatation and mass in the intrahepatic bile duct. To detect the lumen of the extrahepatic bile duct next to the portal vein, we repeatedly moved the probe diagonally toward the midline of the abdomen, descending along the axis from the middle of the right costal arch and moving it toward the pelvis. Doppler mode ultrasound is also useful in this procedure. Once the portal vein is located, the extrahepatic duct along it is traced. An alternative method involves imaging from a left lateral decubitus approach to detect the intrapancreatic bile duct, then fixing on it and rotating the probe about 90° to allow detection and following the image of the duct laterally. Pathologic conditions include bile duct dilatation, intraluminal lesions, and changes in the wall of the bile duct. To visualize the gallbladder, first locate the gallbladder bed as a landmark and then follow it to the hepatoduodenal ligament. Particular care is necessary in imaging the neck and fundal portion of the gallbladder, which are easily overlooked. Note the size of the gallbladder and the condition of the lumen and gallbladder wall. The entire pancreas is observed along its long axis using the splenic vein as a landmark. The bifurcation of the splenic vein is seen near the pancreatic tail, but because imaging is often insufficient using wide scanning, depiction from the left intercostals space may be better. The size of the pancreas, condition of the main pancreatic duct, and presence of any dilatation or mass must be carefully noted.

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Ultrasound imaging is now the tool of choice for evaluating and understanding lower urinary tract symptoms (LUTS), particularly those in males. Measurement of postvoid residual urine has been exclusively replaced by ultrasound. Ultrasound imaging of the bladder is essential in the screening of bladder disorders that could possibly present LUTS. Ultrasound-estimated bladder weight is highly promising in evaluating histologic changes in the bladder and diagnosing neurogenic bladder and obstruction of the bladder outlet. Transrectal ultrasound of the prostate is clinically useful in both the diagnosis of benign prostatic hyperplasia and the evaluation of obstruction by measuring the resistive index of prostatic vessels with Doppler imaging. Voiding transrectal ultrasound can be used to evaluate disorders at the bladder neck and clarify the urodynamics of posterior urethra. Its noninvasiveness and ease of application should make ultrasound imaging indispensable in the diagnosis of LUTS.

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The newer diagnostic ultrasound equipments such as a color Doppler equipment and/or a harmonic imaging equipment require higher pressure ultrasound than the conventional B-mode imaging systems. We investigated the temperature rise in soft tissue caused by ultrasound irradiation using a simulation program for a single disk transducer and a phased array focused transducer . The simulation program consisted of two codes capable of estimating the temperature distribution in various media. First, the sound pressure distribution in media was calculated by the finite-difference time-domain (FDTD) method. There are two types of FDTD codes, i.e., for a fluid model and an elastic model, to calculate the pressure in soft tissue and the stress in bone. The common heat conduction equation (HCE) method was used to calculate the thermal conduction profile generated by absorption of ultrasound. It is very important to show that this simulation program would be able to confirm the exact temperature distribution in the media. This paper describes a comparison between two-dimensional FDTD-HCE simulation and measurement of the temperature rise in soft tissue phantom with mimic bone to show the validity of this method. Agar and acrylic plates were used for the sham soft tissue and human bone. The main focus of the study was the reflection effect from the mimic bone when the absorption coefficient of the agar phantom was about 0.5dB/cm/MHz, which is the typical absorption value of soft tissue. The measuring results without mimic bone agreed well with the simulation results. The measuring results with bone, however, did not agree with the simulation near the bone surface. It was clearly seen that the reflected waves increased the temperature in front of the bone.

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Purpose: Venous ultrasonography and measurement of D-dimers were performed to evaluate their efficacies in the diagnosis of deep venous thrombosis in patients undergoing routine urologic surgery. Materials and Methods: The subjects in this study were 56 patients who underwent urologic surgery at our hospital between January 2005 and March 2006. We performed ultrasonographic examination and measurement of D-dimers before and after the surgery. Thirty-nine of the 56 patients underwent transurethral surgery, and seventeen underwent open urologic surgery. We carried out ultrasonographic examination for the detection of deep venous thrombosis from the bilateral iliac veins to the calf muscle veins. Results and discussion: None of the patients had any evidence of deep venous thrombosis either before or after the operations. As for the D-dimer levels, there were no transurethral surgery patients who had D-dimer levels in the positive range; however, six of the 17 patients who underwent open urological surgery showed D-dimer levels in the positive range. Conclusion: In cases undergoing transurethral surgery, routine venous ultrasonography may not be needed if serum D-dimer concentrations can be measured after the operation.

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The patient was a 64-year-old woman under treatment for hypertension who suddenly experienced abdominal pain on October 14, 2005. Oral medication was administered, but her pain persisted, and after 1 week, she presented herself at our hospital. Contrast-enhanced abdominal CT showed an isolated dissection of the superior mesenteric artery (SMA) 7 to 8 cm from its origin and having a true but severely narrowed lumen and a thrombotic false lumen. Ischemia of the small intestine was considered. The ultrasonographic findings coincided with those of the contrast-enhanced abdominal CT scan. Because the patient was in a generally good state of health and her blood flow was maintained, she was managed with such conservative treatment as fasting. On the 8th day of hospitalization, small vessels, branching from the trunk of the superior mesenteric artery, which were not originally depicted in ultrasound images, had emerged. On the 13th day, the number of these side branches was found to have increased. These ultrasonographic changes were consistent with improvement in the symptoms and ischemic images noted in the small intestine demonstrated by contrast-enhanced abdominal CT. The false lumen was no longer observable 4 months later. Both ultrasonography and contrast-enhanced abdominal CT were useful in diagnosing and observing the clinical course of this case of dissection of the superior mesenteric artery. Of the two modalities, ultrasonography offered special advantages, including dynamic visualization of vascular flow from various angles and sparing the patient exposure to radiation.

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