Shuji Nagata

Diffusion-weighted imaging of soft tissue tumors: usefulness of the apparent diffusion coefficient for differential diagnosis.

PurposeWe evaluated the efficacy of using the apparent diffusion coefficient (ADC) to differentiate soft tissue tumors.Materials and methodsWe examined 88 histologically proven tumors (44 benign, 8 intermediate, 36 malignant) using diffusion-weighted magnetic resonance images. Images of the tumors were obtained using a single-shot, spin-echo type echo-planar imaging sequence. The tumors were classified histologically as myxoid or nonmyxoid. We then compared the ADC values of the myxoid and nonmyxoid tumors; the benign and malignant myxoid tumors; and the benign, intermediate, and malignant nonmyxoid tumors.ResultsThe mean ADC value of the myxoid tumors (2.08 ± 0.51 × 10−3 mm2/s) was significantly greater than that of the nonmyxoid tumors (1.13 ± 0.40 × 10−3 mm2/s) (P < 0.001). There was no significant difference in the mean ADC values between benign myxoid tumors (2.10 ± 0.50 × 10−3 mm2/s) and malignant myxoid tumors (2.05 ± 0.58 × 10−3 mm2/s). The mean ADC value of benign nonmyxoid tumors (1.31 ± 0.46 × 10−3 mm2/s) was significantly higher than that of malignant nonmyxoid tumors (0.94 ± 0.25 × 10−3 mm2/s) (P < 0.001).ConclusionThe ADC value might be useful for diagnosing the malignancy of nonmyxoid soft tissue tumors.

CT Image Fusion for 3D Depiction of Anatomic Abnormalities of the Hepatic Hilum

OBJECTIVE The purpose of this article is to show how CT image fusion with 3D reconstruction is used to depict in detail the anatomic structures of the hepatic hilum in the presence of hepatobiliary abnormalities. CONCLUSION CT image fusion is a comprehensive imaging technique for preoperative evaluation of the blood vessels and bile ducts of the hepatic hilum.

Giant cell-rich osteosarcoma of the distal femur : radiographic and magnetic resonance imaging findings

We report a case of giant cell-rich osteosarcoma in the right distal femur of a 32-year-old man. Giant cell-rich osteosarcomas are sometimes difficult to distinguish from giant cell tumors by age, location, magnetic resonance imaging findings, and pathology. Radiography may be useful in the diagnosis of giant cell-rich osteosarcoma.

A case of metastasizing pleomorphic adenoma in the maxillary bone appearing twenty years after initial resection of pleomorphic adenoma of the hard palate

Metastasizing pleomorphic adenoma (MPA) is the inexplicable metastasis of a histologically benign pleomorphic adenoma (PA). Approximately 50 cases have been reported. A 62‐year‐old woman noticed pain in the upper molar area. Her medical history included an operation for PA in the hard palate that was performed 20 years previously. On imaging, four relatively well‐defined lesions were demonstrated in the maxillary bone. She underwent an operation for these lesions. Each lesion revealed the same histological features. Morphological findings displayed typical features of PA. Immunohistochemical staining showed that tumor cells of both primary and metastasizing lesions were positive for pleomorphic adenoma gene (PLAG) 1, which is a sensitive marker for PA. Gene fusions involving PLAG1 were examined by reverse transcription‐polymerase chain reaction. However, no gene rearrangements of PLAG1 were found. We report here on a case of MPA in the maxillary bone, which appeared 20 years after resection of the primary tumor and review the relevant literature.

Ultraselective embolization using a 1.7-Fr catheter and soft bare coil for small intestinal bleeding.

Abstract Objective: We aimed to evaluate the safety and efficacy of embolization using a 1.7-Fr catheter and soft bare coil to treat acute small intestinal bleeding. Material and methods: Subjects were five consecutive patients who experienced onset of melena with small intestinal bleeding and underwent transcatheter arterial embolization with 1.7-Fr catheters and 0.010-inch detachable bare coils (five procedures in total). Technical success, clinical success, relative post-procedural complications, arterial bleeding source and cause, and relationship between coagulopathy and embolization efficacy were examined by capsule endoscopy. Results: We achieved 100% technical and clinical success for the five transcatheter arterial embolizations. All catheterizations of the vasa recta of the bleeding artery (jejunal artery, n = 2; ileal artery, n = 3) were possible with a 1.7-Fr catheter. We achieved high embolization efficacy in two patients with coagulopathy. No rebleeding, intestinal ischemia, or necrosis was observed on follow-up capsule endoscopy. We confirmed that peptic ulcers/ulcer scars were the cause of bleeding for all patients. Conclusion: Embolization with 0.010-inch coils using a 1.7-Fr catheter and catheterization of the vasa recta of bleeding vessels was effective and safe for treating small intestinal bleeding.

Chondrosarcoma arising within a radiation-induced osteochondroma several years following childhood total body irradiation: case report.

Malignant degeneration arising in radiation-induced osteochondromas is extremely rare. We report a case of a 34-year-old man with a chondrosarcoma arising from an osteochondroma of the left posterior eighth rib that developed following total body irradiation received as part of the conditioning regimen prior to bone marrow transplantation at age 8. To our knowledge, this is only the fourth reported case of a chondrosarcoma arising within a radiation-induced osteochondroma and the first case occurring following childhood total body irradiation.

Internal Coil Packing for Mesh Occlusion Device

1. Stavropoulos SW, Ge BH, Mondschein JI, Shlansky-Goldberg RD, Sudheendra D, Trerotola SO. Retrieval of tip-embedded inferior vena cava filters by using the endobronchial forceps technique: experience at a single institution. Radiology 2015; 275:900–907. 2. Aytemir K, Yorgun H, Canpolat U, et al. Initial experience with the TightRail Rotating Mechanical Dilator Sheath for transvenous lead extraction. Europace 2016; 18:1043–1048. 3. Kuo WT, Tong RT, Hwang GL, et al. High-risk retrieval of adherent and chronically implanted IVC filters: techniques for removal and management of thrombotic complications. J Vasc Interv Radiol 2009; 20:1548–1556.

Infantile hemangioma of the liver in an adult: A case report and review of the literature

Infantile hemangioma (IH), a representative vascular liver tumor, usually occurs in infancy or early childhood but rarely in adults. In this study, we describe a case of IH in a 47-year-old female and we also review the literature. A plain computed tomography (CT) image revealed five hypoattenuating masses in the liver. A dynamic study revealed the masses appeared to be well-enhanced in the arterial phase, and were considered to be high-flow hemangiomas. The tumors appeared as hypointense tumors on the T1-weighted images and as hyperintensities on fat-suppression T2-weighted images. Following the administration of gadolinium ethoxybenzyl diethylenetriamine pentaacetic acid (Gd-EOB-DTPA), tumors appeared to be well-enhanced in the arterial phase. In the portal phase, tumors demonstrated isointensity compared with the surrounding liver parenchyma, and hypointensity in the equilibrium and hepatobiliary phases. The apparent diffusion coefficient (ADC) values ranged from 2.0 to 2.4x10(-3) mm2/sec. Microscopically, the tumors were composed of numerous capillary-like small vessels lined with plump endothelial cells, arranged in a single layer without mitoses, and small bile ducts were trapped and scattered within the tumor. These findings were considered to be characteristic of IH. To the best of our knowledge, this case is the third report on IH in adults.

Mature Cystic Teratoma With an Element of Hepatocellular Carcinoma in Anterior Mediastinum: Magnetic Resonance-Pathologic Correlation

A teratoma is a germ cell tumor (GCT) commonly composed of somatic tissues derived from at least 2 of the 3 germ layers, that is, ectoderm, endoderm, and mesoderm. Teratomas account for <10% of all mediastinal masses.1 The frequency of a mature teratoma in mediastinal masses is ∼6% (27/445)2, whereas the presence of hepatic tissues in a mature teratoma is extremely rare.3 Recently, 2 GCTs with hepatocellular carcinoma (HCC) components were reported: one was a testicular teratoma,4 and the other was a germinoma in the brain.5 To the best of our knowledge, this is the first report of a mature cystic teratoma with an element of HCC arising in the anterior mediastinum.

The Value of MRI and Clinical Features in Differentiating Between Cellular and Fibrous Solitary Fibrous Tumors.

OBJECTIVE The purpose of this study is to evaluate the usefulness of MRI in differentiating between fibrous and cellular solitary fibrous tumors (SFTs). MATERIALS AND METHODS This retrospective study included 17 patients with histopathologically confirmed SFTs, including 10 patients with fibrous SFTs and seven patients with cellular SFTs. We evaluated the differences between fibrous and cellular SFTs with regard to clinical data and MRI findings, such as tumor margin definition, signal intensity, heterogeneity on T1- and T2-weighted images, presence of capsules, intratumoral cystic changes, flow signal void, perilesional edema, enhancement pattern on dynamic contrast-enhanced MRI (DCE-MRI), and mean apparent diffusion coefficient (ADC) values. RESULTS Statistically significant differences in fibrous and cellular SFTs were noted with respect to signal intensity on T2-weighted images (p = 0.044, by Fisher exact test) and enhancement patterns on DCE-MRI (p = 0.005, by Fisher exact test). Specifically, on T2-weighted images, five of the fibrous SFTs had high signal intensity, and the other five had signal isointensity, whereas all seven cellular SFTs had high signal intensity. On DCE-MRI, fibrous SFTs tended to show a gradual increase in enhancement, whereas cellular SFTs showed a rapid initial enhancement pattern. The mean (± SD) ADC value for cellular SFTs was 1.39 ± 0.35 × 10-3 mm2/s, whereas that for fibrous SFTs was 1.37 ± 0.48 × 10-3 mm2/s, with no statistically significant difference noted between the two (p = 0.755, by Fisher exact test). CONCLUSION Fibrous SFTs have nonspecific findings with regard to signal intensity on T2-weighted MR images and enhancement patterns on DCE-MRI, whereas cellular SFTs show high signal intensity on T2-weighted images and rapid initial enhancement on DCE-MRI.