Utility of ultrasonography for predicting indications for tolvaptan in patients with autosomal dominant polycystic kidney disease.

PURPOSE: Tolvaptan is the first approved treatment for autosomal dominant polycystic kidney disease (ADPKD) that targets a mechanism directly contributing to the development and growth of renal cysts. We investigated the ability of ultrasonography to predict total kidney volume (TKV) of 750 mL or more, which is an indication for tolvaptan therapy in patients with ADPKD. METHODS: A total of 46 patients with ADPKD were evaluated. The most statistically appropriate measurement based on ultrasonography for predicting TKV determined by computed tomography (CT) was assessed. RESULTS: TKV determined by CT was 796.8 (508.8-1,560.3) mL. The median length, anteroposterior distance, and mediolateral distance determined using ultrasonography were 15.7 cm, 7.6 cm, and 7.6 cm in the left kidney, and 13.4 cm, 6.9 cm, and 7.2 cm in the right kidney, respectively. Multivariate regression analysis showed that total kidney length (left and right) [variance inflation factor (VIF), 9.349] and total mediolateral distance (left and right) (VIF, 3.988) were independently associated with TKV. The correlation (r) between the logarithm of TKV determined by CT and total mediolateral distance determined using ultrasonography was 0.915 (p < 0.001). The linear regression equation was log (total kidney volume) = 1.833 + 0.075 × total mediolateral distance (left and right) based on ultrasonography. The area under the receiver operating characteristic curve for total mediolateral distance determined using ultrasonography to predict TKV of 750 mL or more was 0.989. Using the total mediolateral distance cut-off value of 14.2 cm, the sensitivity and specificity were 96.0% and 100.0%, respectively. CONCLUSION: Total mediolateral distance determined using ultrasonography can predict TKV in patients with ADPKD.

Multiple Inflammatory Pseudotumors of the Liver Demonstrating Spontaneous Regression: A Case Report.

Inflammatory pseudotumor (IPT) of the liver is a rare benign disease. IPTs generally develop as solitary nodules, and cases with multiple lesions are uncommon. We herein report a case of multiple IPTs of the liver that spontaneously regressed. A 70-year-old woman with a 10-year history of primary biliary cholangitis and rheumatoid arthritis visited our hospital to receive a periodic medical examination. Abdominal ultrasonography revealed multiple hypoechoic lesions, with a maximum size of 33 mm, in the liver. Contrast-enhanced computed tomography revealed low-attenuation areas in the liver with mild peripheral enhancement at the arterial and portal phases. We first suspected metastatic liver tumors, but fluorodeoxyglucose positron emission tomography, magnetic resonance imaging and contrast-enhanced ultrasonography suggested the tumors to be inconsistent with malignant nodules. A percutaneous biopsy showed shedding of liver cells and abundant fibrosis with infiltration of inflammatory cells. Given these findings, we diagnosed the multiple tumors as IPTs. After careful observation for two months, the tumors almost vanished spontaneously. Physicians should avoid a hasty diagnosis of multiple tumors based solely on a few clinical findings, and a careful assessment with various imaging modalities should be conducted.

A New Ultrasonographic "Fluttering Sign" for Hepatic Hemangioma.

The aim of the study described here was to clarify the diagnostic value of the fluttering sign, a new sign that characterizes hepatic hemangiomas in gray-scale ultrasonography (US). It refers to a phenomenon in which the speckled echogenicity inside the hemangioma changes continuously and seems to be moving. A total of 172 hemangiomas diagnosed with contrast-enhanced US were evaluated. The fluttering sign was found in 123 of 172 hemangiomas (71.5%). Its prevalence was significantly higher than that of the marginal strong echo (89/172, 51.7%, p < 0.001), posterior acoustic enhancement (103/172, 59.9%, p = 0.031) and chameleon sign (100/172, 58.1%, p = 0.013). In addition, the fluttering sign was observed significantly more frequently in mixed or hypo-echoic tumors than in hyper-echoic tumors (p < 0.001), relatively large tumors (p < 0.001) and tumors that were less than 5 cm from the body surface (p = 0.015). The fluttering sign in gray-scale US has great potential to be a new complementary sign for the diagnosis of hemangioma.

New malignant grading system for hepatocellular carcinoma using the Sonazoid contrast agent for ultrasonography.

BACKGROUND: The ultrasonography contrast agent Sonazoid provides parenchyma-specific contrast imaging (Kupffer imaging) based on its accumulation in Kupffer cells. This agent also facilitates imaging of the fine vascular architecture in tumors through maximum intensity projection (MIP). We examined the clinical utility of the malignancy grading system for hepatocellular carcinoma (HCC) using a combination of 2 different contrast-enhanced ultrasonography images. METHODS: We studied 121 histologically confirmed cases of HCC (well-differentiated, 45; moderately differentiated, 70; poorly differentiated, 6). The results of Kupffer imaging were classified as (1) iso-echoic pattern or (2) hypo-echoic pattern. The MIP patterns produced were classified into one of the following categories: fine, tumor vessels were not clearly visualized and only fine vessels were visualized; vascular, tumor vessels were visualized clearly; irregular, tumor vessels were thick and irregular. Based on the combined assessment of Kupffer imaging and the MIP pattern, the samples were classified into 4 grades: Grade 1 (iso-fine/vascular), Grade 2 (hypo-fine), Grade 3 (hypo-vascular), and Grade 4 (hypo-irregular). RESULTS: The distribution of moderately and poorly differentiated HCCs was as follows: Grade 1, 4 % (1/24); Grade 2, 52 % (15/29); Grade 3, 85 % (44/52); and Grade 4, 100 % (16/16). The grading system also predicted portal vein invasion in 72 resected HCCs: Grade 1, 0 % (0/4); Grade 2, 13 % (1/8); Grade 3, 23 % (11/48); and Grade 4, 67 % (8/12). CONCLUSIONS: This new malignant grading system is useful for estimation of histological differentiation and portal vein invasion of HCC.