Superb microvascular imaging (SMI) findings of splenic artery pseudoaneurysm: a report of two cases.

Splenic artery pseudoaneurysm (SAPA) is a relatively infrequently encountered but clinically important vascular change, because it carries a high risk of rupture that warrants prompt treatment regardless of its size. Thus, sufficient knowledge is indispensable when seeing chronic pancreatitis patients or post-traumatic patients. Here, we report two such cases. The first case was a 52-year-old woman known to have chronic pancreatitis who presented with hematemesis and hemodynamic instability in which X-ray computed tomography (CT) and color Doppler sonography (CDS) had difficulty visualizing slow blood flow in SAPA, but superb microvascular imaging (SMI) clearly demonstrated the slow blood flow in SAPA, prompting our therapeutic decision to perform rapid embolization. The second case was a 51-year-old woman with post-traumatic SAPA in which 3D SMI enabled us to understand more clearly the topographic relationship between multiple SAPAs as compared with conventional US, leading to a decision to provide immediate surgical treatment. SMI was thought to provide a new insight into the US diagnosis of SAPA. When examining patients suspected of having a SAPA, SMI is an indispensable diagnostic tool at present.

Sonographic findings in two cases of lymphangioma of the mesocolon in adults.

Lymphangioma of the mesocolon is very rare. We report two cases of surgically resected and histologically proven mesocolic lymphangioma in adults. In both cases, ultrasound revealed a large cystic mass with multiple thin septa in the lower abdomen. A peculiar finding was the large craniocaudal sliding movement of the mass synchronized with the patient's respiration, which was a clue to the diagnosis of mesenteric lymphangioma. © 2017 Wiley Periodicals, Inc. J Clin Ultrasound 46:78-81, 2018.

Wire-guided biliary cannulation technique does not reduce the risk of post-ERCP pancreatitis: multicenter randomized controlled trial.

AIM: To evaluate the effect of wire-guided biliary cannulation (WGC) on the prevention of post-endoscopic retrograde cholangiopancreatography (ERCP) pancreatitis (PEP). METHODS: We investigated the impact of the WGC technique on the incidence of PEP by comparing the conventional cannulation (CC) technique in selective bile duct cannulation during ERCP with a cross-over design in a prospective multicenter randomized controlled trial and the potential risk factors for PEP. This involved six tertiary referral centers and three university hospitals. A total of 322 patients with indications for ERCP requiring selective biliary cannulation were enrolled from April 2008 to March 2009. RESULTS: One hundred and sixty-three patients were assigned to the WGC group and 159 to the CC group. The incidence of PEP was the same between the groups (6.1% vs 6.3%, P = 0.95). Primary successful biliary cannulation was achieved in 136 patients (83%) in the WGC group and in 138 (87%) in the CC group (P = 0.40). The mean time required for primary successful biliary cannulation was 7.4 ± 8.3 min and 7.2 ± 7.9 min, respectively (P = 0.83). Multivariate analysis demonstrated that accidental guidewire insertions and unintended injections of contrast into the main pancreatic duct were the only independent risk factors for PEP (P = 0.001, relative risk [RR]: 8.70, 95% confidence interval [CI]: 2.46-30.81). CONCLUSION: The WGC technique does not reduce the risk of PEP and also does not improve the success rate of selective bile duct cannulation.

Sonographic detection of an aneurysm of the gastroepiploic artery.

Gastroepiploic artery aneurysm (GEAA) is very rare.1 Furthermore, most GEAA cases are diagnosed after their rupture. We report a case of asymptomatic GEAA. The patient was a 61-year-old man. Sonography (US) revealed a 2-cm anechoic mass in the epigastrium near the anterior abdominal wall. Color Doppler US and contrast-enhanced US showed arterial flow within the mass leading to the diagnosisof visceral artery aneurysm. CT and angiography confirmed the diagnosis of right GEAA, and the aneurysm was treated successfully with embolization. Follow-up US 6 months later confirmed the absence of blood flow within the lesion.

Painful hepatic hemangioma: report of a case with an emphasis on sonographic findings.

Hepatic hemangiomas are usually asymptomatic and very rarely produce abdominal symptoms. We report a painful 10 × 9 cm hemangioma situated at the hepatic surface of segment 6. The lesion showed a heterogeneous internal structure, composed irregularly of hyperechoic and hypoechoic areas, and it also showed weak posterior echo enhancement. Contrast-enhanced US showed the so-called fill-in pattern, leading to the diagnosis of hepatic hemangioma. The patient's abdomen showed no other abnormal findings, which stressed the relationship between the hemangioma and the patient's symptoms. When the diagnosis of hepatic hemangioma is conclusive, surgical therapy is indicated only in patients with severe symptoms. Our patient was considered to be a candidate for enucleation of the lesion. Histopathologically, the lesion included no areas of hemorrhage or necrosis, and the patient's abdominal pain was likely due to distension of the liver capsule. After surgery, the patient was completely free of symptoms, and enucleation was considered to be appropriate.

Asymptomatic emphysematous cholecystitis.

Emphysematous cholecystitis (EC) is a life-threatening complication of acute cholecystitis. Its clinical manifestations are usually vague, but asymptomatic cases are very rare. We present such a case with an emphasis on sonographic (US) findings. In this case, detection of gas echoes in the gallbladder wall and the surrounding hepatic tissue led us to an appropriate treatment. US is now the technique of first choice for diagnosing gallbladder diseases, and knowledge of US findings encountered in this case can help prevent a hazardous delay in emergent treatment.

Portal gas in a diabetic patient under pharmacotherapy with an alpha-glucosidase inhibitor: report of a case with emphasis on US findings.

Portal gas is relatively rare, and its relation to ischemic bowel diseases has been emphasized. We report the case of a 56-year-old diabetic man under pharmacotherapy with an alpha-glucosidase inhibitor in which portal gas was incidentally detected by ultrasound (US). It showed multiple echo spots moving in the portal vein. Doppler signals confirmed them to be bidirectional and spiky, which immediately led to the diagnosis of portal gas. A change in oral antidiabetic drug caused the portal gas to disappear. We stress the usefulness of US and Doppler US for detecting and diagnosing portal gas. Although detailed analysis of a larger series of diabetic patients under this therapy is needed to draw a definitive conclusion, our observation merits attention. We also briefly review the literature.

Clinical efficacy of contrast-enhanced ultrasonography (CEUS) in the diagnosis of ruptured hepatocellular carcinoma (HCC).

PURPOSE: To evaluate the role of contrast-enhanced ultrasonography (CEUS) in the diagnosis of ruptured hepatocellular carcinoma (HCC). METHODS: CEUS and angiography were performed in ten cases of ruptured HCC. We evaluated whether this technique allowed us to determine the bleeding point by observing an extravasation of contrast media into the ascites. RESULTS: In four of the ten cases, CEUS demonstrated an extravasation of Levovist into ascites. Angiography showed an extravasation of contrast medium in three of these four cases. In three of the remaining six cases, in which CEUS did not show the presence of contrast medium in ascites, angiography demonstrated an extravasation. In eight cases, it yielded cessation of bleeding. In two cases, embolization was not successful. The bleeding point was not determined by CEUS or angiography in one case. CONCLUSION: CEUS allows us to differentiate active bleeding (presence of contrast medium in the ascites) from nonactive bleeding.

Malignant triton tumor in a patient with neurofibromatosis type 1.

We report a case of neurofibromatosis type 1 (NF1) complicated by a malignant triton tumor (MTT), with an emphasis on B-mode sonographic (US) and contrast-enhanced US (CEUS) findings. To the best of our knowledge, this is the first report describing CEUS findings of MTT. The mass was poorly demarcated and composed of an internal echogenic area and an outer hypoechoic zone. CEUS findings showed the outer zone to be strongly enhanced, and the internal area was very poor in blood flow because of necrotic tissues.

Rupture of liver metastasis: report of a case with an emphasis on contrast-enhanced US.

We present a case of liver metastasis from an uterine leiomyosarcoma in which contrast-enhanced ultrasonography (CEUS) helped determine the bleeding point and prevented a delay in devising diagnostic and therapeutic strategies. CEUS allowed us to differentiate active from nonactive bleeding on the basis of presence or absence of contrast extravasation in the ascites. CEUS is the first examination performed when liver tumor rupture is suspected. Reference to the preangiographic CEUS results is expected to provide a road map for angiography.

Portal gas in a patient with acute obstructive cholangitis: report of a case with emphasis on US findings.

Portal gas is relatively rare, and its relationship to ischemic bowel diseases has been emphasized. We report the case of a 70-year-old woman with acute obstructive cholangitis in whom portal gas was detected by ultrasonography (US) but not by computed tomography (CT). The former showed multiple echo spots moving in the portal vein. Doppler signals confirmed them to be bidirectional and spiky, which immediately led to the diagnosis of portal gas. Immediate appropriate antibiotic treatment and biliary drainage yielded the disappearance of the portal gas. We stress the usefulness of US and Doppler US for detecting and diagnosing portal gas. Our observation suggests that when portal gas is detected by US, the possibility of cholangitis should be included in the differential diagnosis.

Contrast-enhanced sonographic findings in a case of hepatobiliary cystadenoma with intracystic bleeding.

Intracystic slow bleeding is very difficult to diagnose using conventional sonography; consequently, a new sonographic technique has been sought. We present a histologically proven hepatobiliary cystadenoma with intracystic bleeding in which contrast-enhanced sonography (CEUS) showed microbubbles oozing from the cyst wall into the cystic cavity 10 minutes after intravenous injection of contrast medium. CEUS is an important diagnostic tool for diagnosing liver tumors, but the CEUS finding of slow intracystic bleeding has not been reported. Our observation suggests that this technique may be a new diagnostic tool for this purpose.

Analysis of refractive artifacts by reconstructed three-dimensional ultrasound imaging.

PURPOSE: Refractive artifacts are frequently encountered in clinical settings, and they have been analyzed on the basis of conventional two-dimensional (2-D) ultrasound (US) images, but this method is restricted to monoplane data and is limited by its inability to assess the three-dimensional (3-D) structure of refractive artifacts. The aim of this study was to evaluate the role of reconstructed 3-D US images in the analysis of refractive artifacts. METHODS: The following representative refractive artifacts were analyzed on the basis of reconstructed 3-D US images: (a) a distorted image of a fine tube behind a cyst (balloon); (b) a deformed image of the bottom of a balloon; and (c) a duplication artifact due to the acoustic lens effect. RESULTS: (a) A tube was imaged as a fine echogenic line with two points of sudden interruption, unlike a curved needle, which was imaged without interruption. (b) 3-D US allowed us to visualize the mode of deformity in the image of the bottom of a fluid-filled balloon in a water bath. When the acoustic velocity in the fluid was greater than that in the surrounding water, the bottom of the balloon appeared to be shrunken. When the acoustic velocity in the fluid was less than that in the surrounding water, the bottom of the balloon appeared to be swollen. (c) When we placed two pieces of white chicken meat in front of a fine needle, the needle was duplicated in the resulting image. In this case, the needle appeared to be vague and fuzzy. In this case, 3-D US did not add further information to the 2-D images. CONCLUSIONS: Our study suggests that reconstructed 3-D US images provide a better understanding of the mode of refractive artifacts than do 2-D US images.

Analysis of posterior echoes using reconstructed vertical ultrasound images.

PURPOSE: To evaluate the role of vertical images reconstructed using 3-D data in the analysis of posterior echoes. METHODS: Reconstructed vertical images of US phantoms with the following artifacts were retrieved and analyzed: acoustic shadowing (clean and dirty); posterior echo enhancement (with/without lateral shadowing); and reverberation artifacts (clean and dirty). RESULTS: For acoustic shadowing, a stone and posterior clean acoustic shadowing were imaged as an echogenic mass or an echogenic ring containing a central echo-free area. However, the stone and dirty acoustic shadowing were imaged as an echogenic mass or an echogenic mass consisting of many fine echo spots disseminated throughout the whole mass. For posterior echo enhancement, when lateral shadowing is present, the cyst and posterior echo enhancement are imaged as a round anechoic mass or a triple circle consisting of a thin anechoic outer rim, an echogenic ring, and an anechoic center. However, when lateral shadowing is absent, they are imaged as a round anechoic mass or a double circle consisting of an echogenic outer rim and an anechoic center. For clean reverberation artifacts and dirty reverberation artifacts, vertical images of clean reverberation artifacts consist of either a homogeneous echogenic area or an absent signal. However, vertical images of dirty reverberation artifacts consist of a homogeneous echogenic area and an area consisting of fine echo spots. CONCLUSION: Our study suggests that reconstructed, previously unattainable, vertical plane images help us better understand the mode of posterior echoes.

Hepatic cyst with intracystic bleeding: contrast-enhanced sonographic findings.

Intracystic bleeding is a relatively rare complication of hepatic cysts, which is very difficult to diagnose by conventional sonography (US). Hence, a new US technique has been sought for this purpose. We present the case of a hepatic cyst with intracystic bleeding in which contrast-enhanced US showed microbubbles oozing from the cyst wall into the cystic cavity. Contrast-enhanced US is now an important diagnostic tool for diagnosing liver tumors, but contrast-enhanced US findings relating to intracystic bleeding have not been reported. Our observations suggest that this technique may be a useful new diagnostic tool for this purpose.