Radiation medicine最新文献

Purpose: Our purpose was to investigate the frequency of intraarticular gas in the glenohumeral joint and sternoclavicular joint, along with the influence of the patient's arm position.

Materials and methods: Multidetector-row computed tomography (MDCT) scan on a total of 104 healthy subjects was investigated retrospectively. Raised-arm and lowered-arm positions were used sequentially, and the presence of intraarticular gas was investigated.

Results: While the arms were in a raised position, intraarticular gas was observed in the glenohumeral joint about 9% of all subjects and in the sternoclavicular joint about 20% of all subjects. Intraarticular gas in the most subjects disappeared when the arms were lowered.

Conclusion: When scanning with the arms in a raised position, intraarticular gas was seen in the glenohumeral and/or and sternoclavicular joint, and disappeared in most cases when the body position was changed. Such intraarticular gas is thought to result from traction of the limbs and is considered clinically insignificant.

Purpose: The purpose of this prospective study was to perform quantitative multidetector computed tomography (MDCT) analysis of pulmonary solid nodules using three parameters (long-short ratio, compactness, and intranodular CT number) and to evaluate the usefulness of each parameter in the differentiation of the nodules.

Materials and methods: Seventy solitary pulmonary nodules with a long axis length of 5-30 mm were examined using one multidetector CT (MDCT) system and one three-dimensional (3D) system, and the findings regarding the three parameters were statistically analyzed among five diseases (hamartoma, organizing pneumonia, adenocarcinoma, squamous cell carcinoma, and metastasis).

Results: The long-short ratio of the pulmonary nodule showed no significant differences among five diseases. The compactness showed significant differences (P < 0.05) in five pairs of diseases. Intranodular CT number showed significant differences (P < 0.05) in three pairs of diseases.

Conclusion: Our results are insufficient for the complete differentiation of pulmonary solid nodules. However, among the three parameters, compactness and intranodular CT number contribute somewhat to the differentiation of pulmonary nodules.

The patient was a 77-year-old man with sudden-onset chest and back pain. Computed tomography angiography (CTA) from the abdomen to the proximal thigh showed an aortic aneurysmal dissection (AAD) and a left deep femoral artery (DFA) aneurysm. The AAD was conservatively managed as there was no sign of increase. The left DFA aneurysm was surgically resected to avoid complications such as rupture, thromboembolism, and limb ischemia. On follow-up CTA obtained 3 weeks later, a spontaneous AVF in a varicose vein of the right DFA was noted. There were no symptoms associated with the AVF, and he was conservatively managed. However, the varicose vein gradually increased, and he underwent successful transarterial catheter embolization (TAE) with metal coils without any complications. After vascular repair of the aneurysm and the AVF of the right DFA, there was no sign of recurrence.

Pleomorphic adenoma is a very rare benign tumor of the breast. Only 70 cases have been reported in the world literature. Recently, we encountered a case of pleomorphic adenoma of the breast and thus present here the mammographic and ultrasonographic findings with the pathology of this rare breast tumor. The patient was a 76-year-old Japanese woman with a right breast mass. The mammography showed a 1.5-cm, lobulated high-density mass with partially ill-defined margins. Ultrasonography revealed an irregularly shaped mass with partially ill defined borders, hypoechoic and heterogeneous internal echoes, and posterior acoustic enhancement. These findings suggested an invasive carcinoma. Awareness of this type of tumor will help in correct diagnosis, in spite of the rarity of this disease.

We present a case of retroperitoneal well-differentiated inflammatory liposarcoma that was extremely difficult to diagnose preoperatively. Computed tomography and magnetic resonance images showed a 5-cm homogeneous soft-tissue mass with a decreased apparent diffusion coefficient and without fat component in the retroperitoneum. Minimal fat stranding was detected around the mass. The preoperative working diagnosis was malignant lymphoma or inflammatory pseudotumor, whereas the final diagnosis after surgery was well-differentiated inflammatory liposarcoma. As a result, only a large component of lymphoid infiltration was recognized as a tumor preoperatively, and minimal fat stranding represented a component of lipoma-like liposarcoma. In this entity, a lipomatous component could easily be missed on radiologic imaging because of the conspicuity of lymphoid infiltration. We should consider the possibility of this variant when we evaluate a retroperitoneal tumor.

Purpose: Our purpose was to determine the optimal antenna spacing to achieve large ablative zones without indentations when microwave ablation is performed with simultaneous activation of two or three antennas.

Materials and methods: Microwave ablation was performed with single-antenna activation and simultaneous activation of two or three antennas with a spacing of 1.5, 2.0, 2.5, or 3.0 cm in explanted bovine livers. Microwave energy was applied for 10 min with a power of 45 W. The shapes and sizes of the ablative zones created were recorded and compared.

Results: The shape of the ablative zone was ellipsoid in the axial plane (along the antenna axis) and spherical in the transverse plane (perpendicular to the antenna axis) in single-antenna ablation. The ablative zones were spherical or ellipsoid in both the axial and transverse planes in two-and three-antenna ablation with an antenna spacing of 2.0 cm or less. Indentations were observed between the ablative zones created by the antennas when the spacing was 2.5 cm or more, reducing the minimum transverse diameter. When two-or three-antenna ablation was performed with a spacing of 2.0 cm or less, the axial and minimum transverse diameters were significantly larger than in single-antenna ablation. The largest volume (almost two or three times the single-activation volume) was achieved in two-or three-antenna ablation with an antenna spacing of 2.0 cm.

Conclusion: We found that simultaneous microwave ablation using multiple microwave antennas creates large ablative zones without indentations when multiple antennas are activated with an antenna spacing of 2.0 cm or less.

Abdominal wall hematoma is an uncommon cause of acute abdominal pain. We report a case of internal oblique hematoma caused by rupture of the subcostal artery in a 57-year-old woman. Ultrasonography (US) showed a hypoechoic mass in the right lateral abdominal wall. Contrast-enhanced computed tomography (CT) showed a large soft tissue mass with extravasation of contrast medium located in the right internal oblique muscle. Angiography showed contrast extravasation from the subcostal artery, and transcatheter arterial embolization was performed successfully.