The association between renal elasticity evaluated by Real-time tissue elastography and renal fibrosis.

BACKGROUND: The progression of chronic kidney disease (CKD) depends on the extent of fibrosis in the kidneys; however, a renal biopsy is necessary to evaluate the severity of renal fibrosis. Real-time tissue elastography (RTE), which measures heartbeat-induced tissue displacement, can assess the elasticity of organs. Here, we aimed to investigate the correlation between renal elasticity and the extent of fibrosis in renal biopsy samples. METHODS: We investigated 29 consecutive patients who underwent a renal biopsy at Ehime University Hospital from February 2018 to August 2019. Renal fibrosis was categorized into three grades, mild (< 25%), moderate (25-50%), and severe (> 50%), based on the total affected area within the biopsy sample. The association between renal elasticity assessed by RTE and the grade of renal fibrosis was evaluated, and a receiver operating characteristic curve was used to distinguish the severity of renal fibrosis. RESULTS: The mean age and estimated glomerular filtration rate (eGFR) were 58.8 years and 55.2 mL/min/1.73 m2, respectively. The median urine protein-to-creatinine ratio was 1.24 g/gCr. The mean renal elasticity of mild, moderate, and severe renal fibrosis was 3.40, 3.98, and 4.77, respectively. Renal elasticity of native kidneys was significantly positively correlated with the grade of renal fibrosis (ρ = 0.529, P = 0.003). At the cutoff point of 3.81, the area under the curve, sensitivity, and specificity were 0.778, 68.4%, and 81.8%, respectively. CONCLUSION: Real-time tissue elastography is a promising, non-invasive method for assessing renal fibrosis in patients with CKD.

Compliance and problems with the surveillance program for HCC diagnosis.

We conducted a multicenter retrospective study for evaluating the background of and diagnostic opportunity for 651 patients with primary hepatocellular carcinoma (HCC). The etiologies were hepatitis B virus (HBV) in 20.0% of patients, hepatitis C virus (HCV) in 36.3%, and non-B non-C (NBNC) in 43.5%. The characteristics of non-alcoholic NBNC HCC patients included low frequency of liver cirrhosis and high frequency of life style-related diseases. The mean diameter of HCC was approximately 4cm. Most patients were diagnosed using ultrasonography and dynamic computed tomography (CT). However, 18.6% of patients were diagnosed using conventional contrast-enhanced CT. Compliance with the surveillance program for HCC diagnosis was 35.4% in HBV carriers and 49.2% in HCV carriers. The main causes of deviation from the program included undiagnosed HBV and HCV carriers, non-compliance with the surveillance program by physicians, and no medical care for HBV and HCV carriers. For an early diagnosis of HCC, it is essential to improve the diagnoses of HBV and HCV carriers, promote the follow-ups of HBV and HCV carriers in hospitals, re-educate physicians, and identify the risk factors of NBNC HCC.

Interleukin-18 deficiency protects against renal interstitial fibrosis in aldosterone/salt-treated mice.

Interleukin (IL)-18 is a member of the IL-1 family of cytokines and was described originally as an interferon γ-inducing factor. Aldosterone plays a central role in the regulation of sodium and potassium homoeostasis by binding to the mineralocorticoid receptor and contributes to kidney and cardiovascular damage. Aldosterone has been reported to induce IL-18, resulting in cardiac fibrosis with induced IL-18-mediated osteopontin (OPN). We therefore hypothesized that aldosterone-induced renal fibrosis via OPN may be mediated by IL-18. To verify this hypothesis, we compared mice deficient in IL-18 and wild-type (WT) mice in a model of aldosterone/salt-induced hypertension. IL-18(-/-) and C57BL/6 WT mice were used for the uninephrectomized aldosterone/salt hypertensive model, whereas NRK-52E cells (rat kidney epithelial cells) were used in an in vitro model. In the present in vivo study, IL-18 protein expression was localized in medullary tubules in the WT mice, whereas in aldosterone-infused WT mice this expression was up-regulated markedly in the proximal tubules, especially in injured and dilated tubules. This renal damage caused by aldosterone was attenuated significantly by IL-18 knockout with down-regulation of OPN expression. In the present in vitro study, aldosterone directly induced IL-18 gene expression in renal tubular epithelial cells in a concentration- and time-dependent manner. These effects were inhibited completely by spironolactone. IL-18 may be a key mediator of aldosterone-induced renal fibrosis by inducing OPN, thereby exacerbating renal interstitial fibrosis. Inhibition of IL-18 may therefore provide a potential target for therapeutic intervention aimed at preventing the progression of renal injury.

Renal shear wave velocity by acoustic radiation force impulse did not reflect advanced renal impairment.

AIM: Acoustic radiation force impulse is a noninvasive method for evaluating tissue elasticity on ultrasound. Renal shear wave velocity measured by this technique has not been fully investigated in patients with renal disease. The aim of the present study was to compare renal shear wave velocity in end-stage renal disease patients and that in patients without chronic kidney disease and to investigate influencing factors. METHODS: Renal shear wave velocities were measured in 59 healthy young subjects (control group), 31 subjects without chronic kidney disease (non-CKD group), and 39 end-stage renal disease patients (ESRD group). Each measurement was performed 10 times at both kidneys, and the mean value of eight of 10 measurements, excluding the maximum and minimum values, was compared. RESULTS: Renal shear wave velocity could be measured in all subjects. Renal shear wave velocity in the control group was higher than in the non-CKD group and in the ESRD group, and no difference was found between the non-CKD group and the ESRD group. Age and depth were negatively correlated to the renal shear wave velocity. In multiple regression analysis, age and depth were independent factors for renal shear wave velocity, while renal impairment was not. There was no difference between the non-CKD group and the ESRD group, even when ages were matched and depth was adjusted. CONCLUSION: Renal shear wave velocity was not associated with advanced renal impairment. However, it reflected alteration of renal aging, and this technique may be useful to detect renal impairment in the earlier stages.

The Importance of Walking for Control of Blood Pressure: Proof Using a Telemedicine System.

BACKGROUND: Regular physical activity (PA), including daily walking, reduces the risk of many chronic diseases, especially hypertension. Pedometer is a potential motivational aid for increasing PA. In the present study, we used a telemedicine system and analyzed the relationship between daily walking, calculated by pedometers, and blood pressure (BP). METHODS: BP was measured at home twice a day (morning and evening) using an oscillometric automatic device. Body weight (BW) and percent body fat (%BF) were measured after BP measurement. Daily walking steps (DWS) were calculated by a pedometer. These daily parameters were transmitted through the Internet to a central server computer and sent to the Medical Health Center. RESULTS: Sixty-nine (N = 69) hypertensive patients were included in this study. The mean follow-up period was 378 days. Electronic data from a pedometer (DWS) were associated with reduced BW, body mass index, and %BF. Hypertensive patients were divided into two groups based on the DWS. In the high DWS group, morning systolic BP and diastolic BP and evening systolic BP were reduced after induction of the telemedicine system. CONCLUSION: A telemedicine system confirmed the usefulness of walking to control BP in hypertensive patients.

Carotid hemodynamics is associated with monocyte count determined by serum homocysteine level in patients with essential hypertension.

To examine the association between pulsatility index (PI) in the common carotid artery (CCA) as a marker of vascular resistance and cardiovascular risk factors, including serum homocysteine and inflammation, 67 hypertensive patients were enrolled. PI correlated with homocysteine and interleukin-6, monocyte count, gender, age and BMI, with monocyte count and age being independent determinants for PI. In turn, monocyte count correlated with homocysteine, tumor necrosis factor-alpha, and HDL-cholesterol, BMI, and gender, with HDL-cholesterol and homocysteine being independent determinants for monocyte count. These results indicated monocyte count determined by homocysteine is associated with arterial stiffness in hypertensive patients.

Fusion Imaging Objectively Demonstrates Improved Pancreas Visualization through Manipulation Techniques: A Prospective Interventional Study.

Objective Abdominal ultrasonography (AUS) is used to screen for abdominal diseases owing to its low cost, safety, and accessibility. However, the detection rate of pancreatic disease using AUS is unsatisfactory. We evaluated the visualization area of the pancreas and the efficacy of manipulation techniques for AUS with fusion imaging. Methods Magnetic resonance imaging (MRI) volume data were obtained from 20 healthy volunteers in supine and right lateral positions. The MRI volume data were transferred to an ultrasound machine equipped with a fusion imaging software program. We evaluated the visualization area of the pancreas before and after postural changes using AUS with fusion imaging and assessed the liquid-filled stomach method using 500 ml of de-aerated water in 10 randomly selected volunteers. Patients This study included 20 healthy volunteers (19 men and 1 woman) with a mean age of 33.0 (21-37.5) years old. Results Fusion imaging revealed that the visualization area of the entire pancreas using AUS was 55%, which significantly improved to 75% with a postural change and 90% when using the liquid-filled stomach method (p=0.043). Gastrointestinal gas is the main obstacle for visualization of the pancreas. Conclusion Fusion imaging objectively demonstrated that manipulation techniques can improve pancreatic visualization.

Comparison of the effect of combination therapy with an angiotensin II receptor blocker and either a low-dose diuretic or calcium channel blocker on cardiac hypertrophy in patients with hypertension.

Left ventricular hypertrophy (LVH) regression is an important issue in hypertensive patients. Patients with LVH who had received the angiotensin receptor blocker (ARB) treatment for 8 weeks and had not reached the target blood pressure level were enrolled in the study. Patients were assigned to either losartan (50 mg)/hydrochlorothiazide (HCTZ, 12.5 mg) group or ARB + CCB group (usual dose of ARB and calcium channel blocker, CCB). After 48 weeks, LV mass index was found to be reduced significantly in the losartan/HCTZ group but not in the ARB + CCB group. These results suggest that combination therapy of an ARB and diuretic has greater potential to cause regression compared with an ARB and CCB.

Effect of renal impairment on the pharmacokinetics of memantine.

The effect of renal impairment on the pharmacokinetics of a single oral dose of memantine (10 mg) was determined in Japanese subjects. Subjects were assigned to four groups based on baseline creatinine clearance (CL(CR)): normal renal function (> 80 mL/min, n = 6), and mild (50 to ≤ 80 mL/min, n = 6), moderate (30 to < 50 mL/min, n = 6), and severe renal impairment (5 to < 30 mL/min, n = 7). Mean memantine maximum plasma concentration (C(max)) was similar in the groups (12.66, 17.25, 15.75, and 15.83 ng/mL, respectively), as was mean time to C(max) (6.2, 5.2, 4.3, and 5.4 h, respectively). However, exposure to memantine determined from mean area under the plasma concentration-time curve was 1.62-, 1.97-, and 2.33-times higher in subjects with mild, moderate, and severe renal impairment, respectively, as compared to controls with normal renal function. Mean memantine plasma elimination half-life increased according to increasing renal impairment (61.15, 83.00, 100.13, and 124.31 h, respectively), while mean cumulative urinary recovery of unchanged memantine in 72 h after dosing decreased according to increasing renal impairment (33.68%, 33.47%, 23.60%, and 16.17%, respectively). These results are the same as those in the previous study on caucasian individuals, when compared per body weight. It is suggested that the dose of memantine should be halved in patients with renal impairment.

Relationship between renal hemodynamics and urinary type IV collagen in patients with essential hypertension.

Urinary type IV collagen excretion (uT4C) in diabetic patients is higher than in normal subjects. In this study, we investigated the relationship between uT4C and renal hemodynamics in 42 patients with essential hypertension. The renal resistive index (RI) is calculated from blood flow velocities measured using pulsed-wave in interlobar arteries. There was a significant correlation between uT4C to creatinine ratio (uT4C/uCr) and age, hemoglobin A1c (HbA1c), and RI. A stepwise regression analysis showed that RI was independently associated with uT4C/uCr. These results indicated that uT4C may be a marker of renovascular stiffness due to glomerulosclerosis in patients with essential hypertension.

[Ultrastructure of glomerular podocyts in the incipient phase of minimal change nephrotic syndrome with thin basement membrane disease].

An 80-year-old woman was referred to the Division of Nephrology at Ehime University Hospital because of leg edema in December 2010. She had been treated with 300 mg of tocopherol for scleroderma since 2007 and treated with 9 mg of prednisolone (PSL) for autoimmune hearing loss since 2010. Due to the occurrence of mild hematuria (5-9/HPF), proteinuria (0.9 g/day) and an increased serum creatinine level (1.31 mg/dL), a renal biopsy was performed. Light microscopy (LM) showed minor abnormality in the glomeruli, and immunohistology showed the absence of deposits of immunoglobulins and complements. Electron microscopy (EM) showed a thin glomerular basement membrane with a limited level of podocyte abnormalities. Due to the findings of intimal thickening of interlobular arteries and subcapsular accumulation of global sclerosis on LM, she was diagnosed with nephrosclerosis and thin basement membrane disease. Four weeks later, her leg edema had increased considerably and urinary protein had increased to 12.4 g/day. The second biopsy showed similar findings in LM and IF as the first biopsy, but EM revealed diffuse foot process effacement. She was diagnosed with minimal change nephrotic syndrome (MCNS) and treated with methylprednisolone pulse therapy followed by 40 mg of oral PSL. Her urinary protein had completely disappeared 6 weeks later. Complete remission with PSL treatment indicates that urinary protein at first renal biopsy was due to MCNS. Our case exhibited podocyte features in the incipient phase of human MCNS.

A Case of Esophagojejunal Variceal Rupture after Total Gastrectomy and Esophagojejunostomy Successfully Treated with Percutaneous Transhepatic Obliteration under Dual-balloon Occlusion of Feeding and Draining Veins.

We present the case of a man in his 60s with bleeding esophagojejunal varices occurring after gastrectomy for gastric carcinoma. Percutaneous transhepatic portography depicted the esophagojejunal varices originated from the jejunal vein and drained into the azygos vein. A 5-French occlusion balloon catheter was wedged into the jejunal vein and a 3-French occlusion balloon catheter into one drainage channel of the esophagojejunal varices via the azygos vein. Selective antegrade jejunal venography under dual-balloon occlusion revealed entire esophagojejunal varices with good stagnated and well-opacified contrast medium. Subsequently, 12 mL of 5% ethanolamine oleate-contrast medium mixture was slowly injected into the esophagojejunal varices. He was discharged without complications one week after the procedure, and abdominal computed tomography demonstrated the disappearance of the esophagojejunal varices six months after the procedure.

Mechanistic insights into intramembrane proteolysis by E. coli site-2 protease homolog RseP.

Site-2 proteases are a conserved family of intramembrane proteases that cleave transmembrane substrates to regulate signal transduction and maintain proteostasis. Here, we elucidated crystal structures of inhibitor-bound forms of bacterial site-2 proteases including Escherichia coli RseP. Structure-based chemical modification and cross-linking experiments indicated that the RseP domains surrounding the active center undergo conformational changes to expose the substrate-binding site, suggesting that RseP has a gating mechanism to regulate substrate entry. Furthermore, mutational analysis suggests that a conserved electrostatic linkage between the transmembrane and peripheral membrane-associated domains mediates the conformational changes. In vivo cleavage assays also support that the substrate transmembrane helix is unwound by strand addition to the intramembrane ß sheet of RseP and is clamped by a conserved asparagine residue at the active center for efficient cleavage. This mechanism underlying the substrate binding, i.e., unwinding and clamping, appears common across distinct families of intramembrane proteases that cleave transmembrane segments.

Osteopontin deficiency protects against aldosterone-induced inflammation, oxidative stress, and interstitial fibrosis in the kidney.

Osteopontin (OPN) has been implicated in the pathology of several renal conditions. Recently, we demonstrated in vitro that aldosterone has important roles in collagen synthesis by inducing OPN (Irita J, Okura T, Kurata M, Miyoshi K, Fukuoka T, Higaki J. Hypertension 51: 507-513, 2008). The aim of the present study was to clarify the roles of OPN in aldosterone-mediated renal fibrosis by infusing aldosterone into either wild-type (WT) or OPN knockout mice (OPN(-/-)). We used uninephrectomized mice treated with aldosterone and high salt to exacerbate renal fibrosis. After 4 wk of treatment with aldosterone, we showed similar increases in systolic blood pressure in both strains of mice. Urine albumin excretion was greater in aldosterone-infused WT mice than in aldosterone-infused OPN(-/-) mice. Immunohistochemical analysis showed high levels of OPN expression in aldosterone-infused WT mice. Interstitial fibrosis and inflammatory infiltrations were increased in aldosterone-infused WT mice compared with either vehicle-infused WT or aldosterone-infused OPN(-/-) mice. These changes were ameliorated markedly by eplerenone treatment in aldosterone-infused WT mice. Aldosterone-infused WT mice also had increased expression of NADPH oxidase subunits compared with aldosterone-infused OPN(-/-) mice. We observed a marked increase in oxidative stress markers in aldosterone-infused WT mice compared with aldosterone-infused OPN(-/-) mice. These results indicate that OPN is a promoter of aldosterone-induced inflammation, oxidative stress, and interstitial fibrosis in the kidney and suggest that inhibition of OPN may be a potential therapeutic target for prevention of renal injury.

The association between ear involvement and clinical features and prognosis in ANCA-associated vasculitis.

OBJECTIVE: The concept of otitis media with ANCA-associated vasculitis (OMAAV) was recently proposed by the study group of the Japan Otological Society. However, little is known about the effect of ear involvement on the clinical features and prognosis of AAV. We investigate this issue in this study. METHODS: We retrospectively examined 36 patients diagnosed with OMAAV and 44 patients diagnosed with AAV without ear involvement (non-OMAAV) at Ehime University Hospital from 2013 to 2018. We collected serological findings including ANCA type and titer, C-reactive protein (CRP), serum creatinine level, organ involved at initial diagnosis, treatment, remission, disease relapse, and mortality from medical records. We investigated whether clinical features and outcomes differed between the OMAAV and non-OMAAV groups. RESULTS: Age, ANCA titer, and CRP at initial diagnosis were not significantly different between the two groups, and the rate of intravenous cyclophosphamide (IVCY) use also did not differ. The proportions of patients with concurrent eye involvement, facial palsy (FP), and hypertrophic pachymeningitis (HCP) were significantly higher in the OMAAV than in the non-OMAAV group (p = 0.005, 0.005 and 0.049, respectively), while both renal and peripheral nerve involvement were significantly less common in OMAAV patients (p = 0.04). Among the 30 patients with renal involvement, serum creatinine level at diagnosis was significantly lower in the OMAAV group (p = 0.04). The mortality rate was 8.3% in OMAAV and 6.8% in non-OMAAV cases, but this difference was not significant. The rate of relapse was 33.3% in OMAAV and 13.6% in non-OMAAV cases; this difference was significant (p = 0.04). CONCLUSIONS: Serological measurements of disease activity did not differ between the groups. Eye involvement, FP, and HCP, however, were significantly more common in AAV with ear involvement. In addition, renal involvement was less common and renal impairment was milder in AAV with ear involvement. These findings can be considered clinical features. The relapse rate was significantly higher in AAV with ear involvement.

Renal resistance index is a marker of future renal dysfunction in patients with essential hypertension.

AIM: In patients with essential hypertension (EHT), the intrarenal resistance index (RI) has been shown to be related to the severity of target organ damage (TOD). Cystatin C is has been reported to be related to TOD in EHT. The aim of the present study was to clarify whether the RI predicts future renal function assessed by cystatin C levels in EHT. METHODS: One-hundred and twelve patients participated. RI and cystatin C were measured at baseline, and 12 months later, cystatin C was measured again. RESULTS: The patients were divided into 2 groups according to RI value: the low RI group (RI<0.7) and the high RI group (RI> or =0.7). After 12 months, cystatin C levels were significantly elevated in the high RI group, whereas the levels remained unchanged in the low RI group. Stepwise regression analysis using the baseline values of RI, age, pulse pressure, HbA1c, cystatin C, log-transformed (ln) C-reactive protein and ln urinary albumin/creatinine as covariates, showed baseline RI was the only independent determinant of the time-related changes in cystatin C levels. CONCLUSION: This finding suggests that the renal RI may be a marker of future renal dysfunction in EHT.

Undercarboxylated osteocalcin is a biomarker of carotid calcification in patients with essential hypertension.

The development of vascular calcification is an active, highly regulated process with similarities to bone formation. Osteocalcin (OC), a vitamin K-dependent protein expressed by osteoblasts, contains 3 gamma-carboxyglutamic acid residues derived from the vitamin K-dependent posttranslational modification of glutamic acid residues. Circulating undercarboxylated OC (ucOC) is increased in vitamin K deficiency and serum ucOC is reported to be a clinical marker of vitamin K status. Vitamin K deficiency is associated with vascular calcification as well as osteoporosis. We evaluated the relationship between ucOC and carotid artery calcification in 92 patients with essential hypertension. Ultrasound of the common carotid artery was performed to identify vascular calcification and subjects were divided into 2 groups: a calcification (+) group and a calcification (-) group. Serum creatinine and ucOC levels were higher in the calcification (+) group than in the calcification (-) group and serum ucOC correlated with serum creatinine. To identify the independent determinant factor for carotid artery calcification, we applied both ucOC and estimated glomerular filtration rate as independent factors in logistic regression analysis. Serum ucOC was an independent determinant of carotid calcification, suggesting that circulating ucOC may be an important biomarker of carotid artery calcification.

Association between cystatin C and inflammation in patients with essential hypertension.

BACKGROUND: Serum cystatin C is not only a marker of renal function but also acts as an independent risk factor for cardiovascular damage, heart failure, and death. It is known that the initiation and progression of these cardiovascular events contributes to renal dysfunction and chronic inflammation. In this study, we investigated the relationship between cystatin C and proinflammatory cytokines. METHODS: Eighty-eight patients with essential hypertension participated in the study, which involved measuring proinflammatory cytokines, tumor necrosis factor (TNF)-α, interleukin (IL)-6, and C reactive protein (CRP). RESULTS: Positive correlations were detected between cystatin C and estimated glomerular filtration rate (eGFR) (r = -0.503, p < 0.001), systolic blood pressure (r = -0.246, p = 0.034), and pulse pressure (r = -0.295, p = 0.010). In contrast, serum creatinine correlated only with eGFR (r = -0.755, p < 0.001) and eGFR correlated only with age (r = -0.339, p = 0.001) and not with the other clinical parameters, whereas cystatin C also correlated with log natural (ln) IL-6 (r = -0.247, p = 0.033) and ln TNF-α (r = -0.405, p < 0.001) but not with CRP (r = -0.188, p = 0.108). In contrast, plasma creatinine and eGFR did not correlate with any of these proinflammatory cytokines. Stepwise regression analysis showed that ln TNF-α, eGFR and pulse pressure were independent determinants of serum cystatin C concentration. CONCLUSION: This study showed that cystatin C is a marker of inflammation as well as renal function.

The relationship between osteopontin and adiponectin in patients with essential hypertension.

The renin angiotensin aldosterone system (RAAS) induces inflammation and accelerates atherosclerosis, contributes to both pro- and anti-inflammatory cytokines. Osteopontin (OPN) is known as a pro-inflammatory cytokine and adiponectin is known as an anti-inflammatory cytokine. C-reactive protein (CRP) not only reflects an inflammatory state but also leads to inflammation. Previous studies clarified that OPN and adiponectin were regulated by RAAS. In this study, we hypothesized that plasma OPN level relates to serum adiponectin level in patients with essential hypertension (EHT). Sixty-two patients (32 females) with EHT were enrolled in this study. They were evaluated for conventional risk factors for atherosclerosis, further plasma aldosterone, plasma OPN, serum adiponectin, and CRP levels were assayed. There were significant gender differences in creatinine, total cholesterol, high-density lipoprotein (HDL) cholesterol, low-denisty lipoprotein(LDL) cholesterol, log transformed (ln) adiponectin and ln CRP. Osteopontin was correlated positively with aldosterone and ln CRP (r = 0.277, p = 0.029, r = 0.278, p = 0.029, respectively), negatively with adiponectin (r = -0.346, p = 0.006). Ln adiponectin was correlated positively with HDL cholesterol (r = 0.373, p = 0.003) and negatively with gender (male as 1), creatinine, triglyceride, aldosterone, and ln CRP (r = -0.55, p < 0.001, r = -0.279, p = 0.028, r = -0.406, p = 0.001, r = -0.307, p < 0.015, r = -0.289, p = 0.023, respectively). Stepwise regression analysis showed that adiponectin was an independent predictor of OPN ß= -0.0339, p = 0.004). Our results suggest that OPN and adiponectin are related to each other underlying the mechanisms of RAAS and inflammation.

Preablation three-dimensional ultrasonography can predict therapeutic effect and local tumor progression after radiofrequency ablation for hepatocellular carcinoma.

PURPOSE: To assess the agreement between ablative margin (AM) predicted by preablation three-dimensional ultrasonography (3D-US) and AM measured on postablation computed tomography (CT)/magnetic resonance (MR) images. METHODS: Sixty patients with 73 hepatocellular carcinoma nodules were enrolled. 3D-US data were collected immediately after puncture by the electrode before ablation. The maximum distance from the electrode to the edge of the tumor in the plane perpendicular to the electrode (C-plane) was defined as "a" and the diameter of the ablation zone as "b". We classified predicted AM into "0.5b - a" ≥0 mm as AM(+) or <0 mm as AM(-), and "0.5b - a" ≥3 mm or <3 mm. RESULTS: Forty-eight nodules (66 %) were visualized in the C-plane. There was an agreement between the predicted and measured AMs for 39 (81 %) of the 48 nodules. Local tumor progression was observed in 3 (7%) of 43 nodules with predicted AM(+) and in 2 (40 %) of 5 nodules with predicted AM(-) but was not observed in any of 21 nodules with predicted AM ≥ 3 mm. The local tumor progression rate was significantly lower for nodules with predicted AM(+) compared with predicted AM(-)(p = 0.03), and for nodules with predicted AM ≥ 3 mm compared with predicted AM < 3 mm (p = 0.04). Local progression was detected in 2 (4.7 %) of 42 nodules with a sufficient AM (≥0 mm) on postablation CT/MR images and in 5 (83.3 %) of 6 nodules with an insufficient AM (<0 mm); the difference in progression rate was significant (p = 0.0008). CONCLUSION: 3D-US allows prediction of the AM before radiofrequency ablation.