Pseudonormal Corticomedullary Differentiation of the Kidney Assessed on T1-weighted Imaging for Chronic Kidney Disease Patients with Cirrhosis.

PURPOSE: We investigated whether corticomedullary differentiation (CMD) increased to a pseudonormal appearance on T1-weighted magnetic resonance (MR) images in patients with chronic kidney disease (CKD) with cirrhosis compared with patients with CKD without chronic liver disease. METHODS: We assessed CMD on T1-weighted MR images of 32 patients with CKD with liver cirrhosis and 32 age-matched patients with CKD without liver cirrhosis, grading CMD visualization as good, moderate, or poor. We calculated quantitative CMD by the ratio of the signal intensity of the cortex to that of the medulla. RESULTS: The proportions of patients in each of the good, moderate, and poor groups differed significantly between those with and without liver cirrhosis (P = 0.048). In patients with CKD with liver cirrhosis, the estimated glomerular filtration rate (eGFR) differed between those with poor CMD and those with good or moderate CMD (P < 0.01) but not between those with good and those with moderate CMD. In patients with CKD without cirrhosis, the eGFR differed significantly among the good, moderate, and poor CMD groups (P < 0.05). We observed no significant correlation between CMD and eGFR in patients with and without cirrhosis (P < 0.05, r = 0.62). CONCLUSION: CMD of the kidney had a pseudonormal appearance on T1-weighted MR imaging in patients with CKD with cirrhosis.

Hepatosplenic and muscular sarcoidosis: characterization with MR imaging.

Sarcoidosis is a multisystem disorder of unknown etiology that involves multiple organs. Computed tomography is the first-line imaging modality for diagnosing sarcoidosis because of its capacity to detect hilar lymphadenopathy and pulmonary lesions. Magnetic resonance (MR) imaging provides good soft tissue contrast that is useful for detecting sarcoidosis in some body parts, including skeletal muscle. Signal intensity on pre- and postcontrast T(1)- and T(2)-weighted imaging may reflect disease activity and the pathological appearance of sarcoidosis. In this review, we demonstrate these conventional MR imaging findings of hepatosplenic and muscular sarcoidosis and describe the usefulness of diffusion-weighted imaging for detecting sarcoidosis.

Assessment of renal impairment by non-contrast-enhanced conventional magnetic resonance imaging: comparison with 99mTc-DTPA renography.

PURPOSE: The aim of this study was to determine whether non-contrast-enhanced magnetic resonance imaging (MRI) can detect three levels of renal impairment by evaluating the differences and agreement with (99m)Tc-diethylenetriamine pentaacetic acid (DTPA) renography. MATERIALS AND METHODS: A total of 28 patients with kidney disease were enrolled in the study. MRI findings, including visual corticomedullary differentiation (CMD) on T1- and T2-weighted imaging (T1WI, T2WI), cortical irregularity, the number of renal cysts, and the volume of the kidney, were evaluated for individual kidneys and pairs of kidneys. The differences and agreement between MRI findings and the three levels of renal impairment based on the glomerular filtration rate (GFR) measured using (99m)Tc-DTPA renography were analyzed. RESULTS: All MRI findings except the number of renal cysts in pairs of kidneys were consistent with the patient's classification. The agreement between the patient's classifications based on GFR and that based on the visual CMD on T1WI and T2WI was almost perfect or substantial in both individual kidneys and pairs of kidneys. CONCLUSION: Non-contrast-enhanced MRI was capable of distinguishing three levels of renal function, including serious renal impairment.

Comparative study of transcatheter renal arterial embolization with and without closed renal circuit: pharmacokinetic and histologic assessment in pigs.

PURPOSE: To assess the degree of renal necrosis and the leakage of absolute ethanol by using two methods: transcatheter renal artery embolization (TAE) and TAE performed with a closed renal circuit (CRC) (TAE/CRC), both performed by using ethanol and iodized oil, in a pig model. MATERIALS AND METHODS: All animal experiments were conducted in accordance with our university guidelines for animal care and experimentation. Fourteen pigs were classified in two groups: standard TAE and TAE/CRC groups. In the TAE/CRC group, the renal artery and vein were occluded with balloon catheters; in the TAE group, only the renal artery was occluded. An emulsion of absolute ethanol (0.5 mL per kilogram of body weight) and iodized oil (emulsion ratio, 4:1) was injected in the renal artery in both groups. In the TAE/CRC group, we aspirated the blood containing the emulsion via the renal vein during arterial infusion. We measured the ethanol concentrations of the systemic circulation. Four days after embolization, the kidneys in both groups were removed and histopathologic examination was performed and results were compared. RESULTS: The mean systemic ethanol concentration was less than 0.1 mg/mL in the TAE/CRC group and 0.28 mg/mL +/- 0.15 (standard deviation) in the TAE group (P < .002). In both groups, about 90% of the kidney was shown histopathologically to have undergone coagulation necrosis (no significant difference). The frequency of venous thrombus formation was significantly lower (P = .009) in the TAE/CRC group. CONCLUSION: TAE/CRC dramatically reduces ethanol leakage to the systemic circulation without a decrease in embolization effect in the normal swine kidney, and it also reduces the likelihood of venous thrombus formation.

A left ventricular lipoma diagnosed on three-dimensional electrocardiogram-gated cardiac computed tomography.

Cardiac lipomas are extremely rare primary benign cardiac tumors. We describe a patient with a chief complaint of ventricular tachycardia associated with a lipoma arising in the left ventricular myocardium. The cardiac lipoma was qualitatively evaluated and its location was accurately determined noninvasively with the use of three-dimensional images reconstructed from data acquired by electrocardiogram-gated cardiac computed tomography (CT). Our experience suggests that high-resolution three-dimensional CT imaging may facilitate the determination of strategies for surgical treatment.

Serial assessment of the development of inflammatory abdominal aortic aneurysm from ordinary atherosclerotic abdominal aortic aneurysm using multidetector-row computed tomographic angiography.

Inflammatory abdominal aortic aneurysm (AAA) is an aortic aneurysm of unknown etiology characterized by a thickened aneurysmal wall, perianeurysmal and retroperitoneal fibrosis, and adhesions to adjacent organs. We encountered a case of inflammatory AAA, which developed from an ordinary atherosclerotic AAA over a period of 14 months, with a rapid increase of 48 mm in the maximum diameter of the aneurysm over 12 days. This report describes the evaluation of the serial change by 16-channel multidetector-row computed tomographic (MDCT) angiography.