[Brain Calcification].

Brain calcification can be either physiological or pathological. Pathological calcification occurs due to a wide spectrum of causes, including congenital disorders, infections, endocrine/metabolic diseases, cerebrovascular diseases, and neoplasms. The patient's age, localization of the calcification, and association with other imaging findings are useful for the correct diagnosis. Dural arteriovenous fistulas with cortical venous reflux should be included in the differential diagnosis of subcortical calcification via CT. MRA should be conducted subsequently. We recently reported the clinical and imaging characteristics of calcified brain metastases in 20 patients. Hemorrhage, necrosis, or degeneration were detected within the lesions in six patients. Both T1WI and T2WI showed a hyperintense mass surrounded by a hypointense rim in one patient. Hemorrhagic brain metastases can mimic cerebral cavernous malformations. Cancer metastasis should be considered as a differential diagnosis when calcified or hemorrhagic masses are detected in middle-aged and elderly patients. We recommend conducting MRI with Gd enhancement.

Fatal acute portal vein thrombosis associated with hepatic cysts in a patient with autosomal dominant polycystic kidney disease.

Autosomal dominant polycystic kidney disease (ADPKD) often involves polycystic liver disease (PLD). In severe cases, PLD can develop various complications. However, fatal acute portal vein thrombosis (APVT) associated with PLD has not been reported. A 64-year-old male reported mild consciousness disorder. He had been under maintenance hemodialysis for end-stage renal disease due to ADPKD with PLD. Because of recurring hepatic cyst infections, he had sustained high levels of C-reactive protein. Regarding the mild consciousness disorder, a diagnosis of hepatic encephalopathy was made based on an elevation of serum ammonia without any other abnormal liver function tests. Several days after his admission, hepatobiliary enzymes elevated, and acute liver failure progressed. Enhanced abdominal computed tomography suggested the possibility of complete occlusion of the portal vein by a thrombus. Based on an absence of obvious portosystemic collaterals, a diagnosis of APVT was made. The patient died 19 days after admission. Patients with PLD with repeated cystic infections have been seen to develop liver failure, and APVT formation may be one cause of the rapid progression of fatal liver failure. In conclusion, this is the first paper to report on the involvement of APVT in patients with PLD.

Fusobacterium necrophorum Endocarditis with Liver Abscesses: A Case Report and Review of the Literature.

Fusobacterium necrophorum is a very rare cause of endocarditis. We herein report a case of F. necrophorum endocarditis with liver abscesses in a 51-year-old woman. This is the first reported case of monomicrobial F. necrophorum endocarditis to present in a patient over 50 years old. We also reviewed 10 reported cases, including the present case. Our review indicated that anaerobic bacteria, including Gram-negative anaerobic bacilli such as F. necrophorum, should be considered in the differential diagnosis of infective endocarditis, especially in patients without preexisting organic heart disease.

Dynamic computed tomography findings of malignant intraductal papillary mucinous tumor compared with invasive ductal adenocarcinoma.

PURPOSE: We evaluated the effectiveness of dynamic computed tomography (CT) imaging in differentiating malignant intraductal papillary mucinous tumor (IPMT) with a large mural nodule from invasive ductal adenocarcinoma (IDAC). MATERIALS AND METHODS: Dynamic CT was done in six IPMT and nine IDAC cases. In the IPMT cases, we made a histological map of the tumor. A region of interest (ROI) was established in the mural nodule of the IPMT, in the IDAC, and in the noncancerous portion of the pancreas. The change of density was analyzed statistically during preenhancement and the early and late phases. These results were compared between the IPMT and IDAC cases. RESULTS: Histologically, most of the mural nodule was papillary adenocarcinoma. In the IPMT cases, the postenhancement density of the mural nodule was significantly higher during the early phase than during the late phase. In IDAC cases, the postenhancement density was significantly higher in the late phase than in the early phase. In the early phase, tumor-pancreas density was significantly higher in the IPMT than in the IDAC. In the late phase, tumor-pancreas density was significantly higher in the IDAC than in the IPMT. CONCLUSION: Dynamic CT is useful for differentiating malignant IPMT with a large mural nodule from IDAC.

Comparison of hydroxyapatite and beta tricalcium phosphate as bone substitutes after excision of bone tumors.

Long-term results are reported in 23 patients and short-term results in 30 patients presenting with bone tumors treated by curettage or resection followed by implantation of hydroxyapatite (HA) or highly purified beta-tricalcium phosphate (beta-TCP), respectively. Mean follow-up was 97 and 26 months in cases involving HA implantation and beta-TCP implantation, respectively. Radiographs revealed HA incorporation into host bone in all but two cases; moreover, no obvious evidence of HA biodegradation was observed. A single patient exhibited late deformity following implantation of HA. All grafted beta-TCP was, at least partially, absorbed and replaced by newly formed bone. The mean period required for the disappearance of radiolucent zones between the ceramics and host bone was 17 weeks in HA and 9.7 weeks in beta-TCP. Highly purified beta-TCP appears to be advantageous relative to HA for surgical intervention in bone tumors consequent to the nature of remodeling and superior osteoconductivity.

Liver metastasis 30 years after enucleation of the left eyeball for choroidal melanoma.

Here, we report a case of 70-year-old female with metastatic choroidal melanoma in the liver, which was detected 30 years after enucleation of the left eyeball. At first, two hypovascular tumors (4cm and 1cm in diameter) were detected in the liver as high-density areas on plain computed tomography (CT). They were demonstrated as hyper- and hypo-intensity lesions on T1- and T2-weighted image of magnetic resonance imaging (MRI), respectively, with superparamagnetic iron oxide uptake. During about 2-years follow-up, the larger tumor did not change significantly in size and in the character. However, the smaller one grew up in size and changed its nature to hypervascular and hyper-intensity on T2-weighted image of MRI. These hypervascular tumors increased in number and in size rapidly. The specimens obtained with tumor biopsy revealed epithelioid tumor cells positive for HMB45 immunohistochemical stain with and without brown pigment, and the tumors were diagnosed as melanoma. The patient underwent transcatheter arterial chemoembolization with cisplatin and epirubicin hydrochloride, and subsequent transcatheter arterial infusion chemotherapy with cisplatin, nimustine and dacarbazine. Unfortunately, however, the tumor rapidly progressed and she died. We discuss the imaging of the melanoma metastasized to the liver with the estimation of doubling time (DT) of the tumors.

Detection and characterization of focal liver lesions: a Japanese phase III, multicenter comparison between gadoxetic acid disodium-enhanced magnetic resonance imaging and contrast-enhanced computed tomography predominantly in patients with hepatocellular carcinoma and chronic liver disease.

OBJECTIVES: To prospectively evaluate the safety and efficacy of combined unenhanced and gadoxetic acid disodium (Gd-EOB-DTPA)-enhanced magnetic resonance (MR) imaging compared with unenhanced MR imaging and triphasic contrast-enhanced spiral computed tomography (CT) for the detection and characterization of focal liver lesions. MATERIALS AND METHODS: The study was reviewed and approved by the institutional review board at each of the 15 centers involved in the study, and informed written consent was given by all patients. In total, 178 patients with suspected focal hepatic lesions (based, in most patients, on CT, tumor marker and ultrasound examinations) underwent combined MR imaging with a single, rapid injection of Gd-EOB-DTPA 0.025 mmol/kg, including T1-weighted dynamic and delayed MR images 20 to 40 minutes postinjection. Triphasic contrast-enhanced CT, the comparator examination, was performed within 4 weeks of MR imaging. Standard of references (SOR) were resection histopathology and intraoperative ultrasonography, or combined CT during arterial portography and CT hepatic arteriography; in cases where, although the major lesions were treated, some lesion(s) were not treated, follow-up superparamagnetic iron oxide-enhanced MR imaging was additionally performed. All images were assessed for differences in lesion detection and characterization (specific lesion type) by on-site readers and 3, blinded (off-site) reviewers. All adverse events (AEs) occurring within 72 hours after Gd-EOB-DTPA administration were reported. RESULTS: Overall, 9.6% of patients who received Gd-EOB-DTPA reported 21 drug-related AEs. A total of 151 patients were included in the efficacy analysis. Combined MR imaging showed statistically higher sensitivity in lesion detection (67.5%-79.5%) than unenhanced MR imaging (46.5%-59.1%; P < 0.05 for all). Combined MR imaging also showed higher sensitivity in lesion detection than CT (61.1%-73.0%), with the results being statistically significant (P < 0.05) for on-site readers and 2 of 3 blinded readers. Higher sensitivity in lesion detection with combined MR imaging compared with CT was also clearly demonstrated in the following subgroups: lesions with a diameter

Perinatal magnetic resonance fetal lung volumetry and fetal lung-to-liver signal intensity ratio for predicting short outcome in isolated congenital diaphragmatic hernia and cystic adenomatoid malformation of the lung.

AIM: To evaluate the usefulness of magnetic resonance imaging (MRI) in predicting the risk of lethal pulmonary hypoplasia in fetuses. METHODS: The subjects consisted of 15 fetuses (29-40 weeks' gestation), including fetuses with major malformation diagnosed on prenatal ultrasonography. MRI using a 1.5 T magnet and half-Fourier acquisition single-shot fast spin-echo sequences were applied to all fetuses at 29-36 weeks. Fetal lung-to-liver signal intensity ratio (LLSIR) was calculated by medians of region-of-interest analysis; estimated fetal bodyweight (FBW), by ultrasonography; and estimated fetal lung volume (FLV), by planimetric measurement of total lung volume. FLV/FBW was also calculated. The presence of the pulmonary hypoplasia in neonates was identified based on clinical and anatomico-pathological findings. Differences in LLSIR and FLV/FBW were analyzed for surviving and non-surviving neonates. RESULTS: Ten surviving neonates had a median LLSIR of 3.00, range: 1.60-4.40, while that in seven non-surviving neonates was 2.21, range: 0.70-3.72; no significant difference was found between the groups. Surviving neonates had a median FLV/FBW of 11.4, range: 7.1-15.7, while that in non-surviving neonates was 4.4, range: 3.1-5.7. FLV/FBW in non-surviving neonates was significantly lower than that of the FLV/FBW for surviving fetuses (P<0.05). CONCLUSIONS: Low FLV/FBW may be useful in prenatally predicting mortality in fetuses with pulmonary hypoplasia.

Cystic teratoma of the diaphragm which mimicked soft tissue lipoma.

We report a case of cystic teratoma of the diaphragm that was considered to be a soft tissue lipoma by the preoperative examination. A magnetic resonance imaging revealed an 8 x 8 cm well-demarcated, homogeneous mass. On T1- and T2-weighted imaging, the mass was isointense to fat. On the fat-suppressed imaging, the signal from the mass was reduced to the same degree as subcutaneous fat. We performed marginal excision. The tumor contained a large number of hairs and oily liquid; and it was connected to the diaphragm.

Imaging of benign hypervascular hepatocellular nodules in alcoholic liver cirrhosis: differentiation from hypervascular hepatocellular carcinoma.

OBJECTIVES: To retrospectively describe imaging analyses of benign hypervascular hyperplastic liver nodules (HHN) that resulted from alcoholic liver cirrhosis and to examine the possibility of imaging differentiation between these nodules and hypervascular hepatocellular carcinoma (HCC). METHODS: Ten histopathologically confirmed HHN arise in alcoholic liver cirrhosis, and 9 HCC were examined. Magnetic resonance imaging (MRI) (10 HHN and 9 HCC), superparamagnetic iron oxide-enhanced T2-weighted MRI (6 HHN and 4 HCC), and dual-phase computed tomography hepatic arteriography (5 HHN and 6 HCC) were performed, respectively. RESULTS: On T1-weighted magnetic resonance images, 7 HHNs showed hyperintensity and 3 showed iso- to hypointensity, and all HCCs showed hypointensity compared with surrounding liver. On T2-weighted magnetic resonance images, 2 HHNs showed hyperintensity and 8 showed iso- to hypointensity. In contrast, 1 HCC showed hypointensity and 8 showed hyperintensity. On superparamagnetic iron oxide-enhanced T2 MRI, all HHNs showed iso- to hypointensity, and all HCCs showed hyperintensity. All HHN and HCCs subjected to dual-phase computed tomography hepatic arteriography showed enhancement on early-phase images and coronalike enhancement on late-phase images. CONCLUSIONS: Imaging findings of highly-well differentiated HCCs possibly overlap with HHN. So, for correct diagnosis of HHN, at first, we should suspect HHN based on clinical findings and MRI findings, and then perform core needle biopsy to verify the radiological diagnosis.

Heterogeneous hepatic enhancement on CT angiography in idiopathic portal hypertension.

BACKGROUND: Idiopathic portal hypertension is an uncommon condition characterized by presinusoidal portal perfusion disturbance without known causes. METHODS: In the present study, portal and arterial perfusion dynamics were evaluated in two cases with idiopathic portal hypertension using computed tomography during arterial portography and hepatic arteriography. Ten cases with liver cirrhosis were also studied as a reference. RESULTS: In cases with idiopathic portal hypertension, portal perfusion was conspicuously heterogeneous and decreased especially at the periphery of the liver where arterial perfusion was reciprocally increased. When the spatial heterogeneity of an enhancement of the liver was quantified using a densitometric analysis of computed tomography during hepatic arteriography images, the densities at the periphery were higher and varied more than those of the inner areas in cases with idiopathic portal hypertension. In contrast, the densities did not vary between the periphery and the inner areas at the cases with liver cirrhosis. CONCLUSIONS: The heterogeneous increase of arterial perfusion in periphery of the liver may be an important feature of idiopathic portal hypertension.

Clinical and imaging features of distended scapulothoracic bursitis: spontaneously regressed pseudotumoral lesion.

OBJECTIVE: To describe clinical and imaging findings of distended scapulothoracic bursitis without scapular snapping, which is often confused with a soft tissue tumor. METHODS: Nine patients (6 male, 3 female; age range: 50-73 years; mean age = 67 years) with distended scapulothoracic bursitis diagnosed by clinical and magnetic resonance (MR) imaging findings were studied. The results of a histologic examination were available in 1 case. RESULTS: All patients presented with painless palpable masses below the scapula, and the initial diagnoses were soft tissue tumors. On MR images, the lesions were 5.5 to 12 cm in maximum diameter (mean = 7.7 cm) and well-demarcated cystic masses situated in the subscapular region between the serratus anterior and the chest wall. There was no solid portion on the cyst walls. The findings of hemorrhage within the bursae were present in all cases. Every mass regressed in size spontaneously after a few to several weeks, and no lesions revealed any malignant findings of sarcomas. CONCLUSIONS: Distended scapulothoracic bursae without scapular snapping resemble soft tissue tumors. They have some specific MR findings; therefore, precise recognition of these findings is important to avoid misdiagnoses and unnecessary treatments.