Bone echinococcosis with hip localization: A case report with evaluation of imaging features

ABSTRACT: Hydatid disease (HD) is a zoonotic parasitic disease caused by the larvae of Echinococcus. Bone echinococcosis is rare, accounting for 0.5% to 4% of all echinococcosis. We describe a particular case of pelvic echinoccosis. A 29-year-old man initially presents with pain in his left hip for several years. After an accidental fall from a tree, he suffered a fracture of the left acetabulum. X-rays and CT scans showed an osteolytic area of the acetabulum with bony cortical interruption. MR imaging demonstrated extensive area of osteostructural alteration of the iliac wing and the left acetabulum due to multiple cysts with enhancement of the walls after administration of Gadolinium-based contrast agents. A CT-guided biopsy of an osteolytic area was performed with diagnosis of echinococcus cyst. He underwent albendazole therapy and subsequently echinococcus cyst exeresis, bone curettage, and left hip arthroplasty. Twenty-two months after surgery, CT scan showed recurrence of disease. After 4 years and 6 months of chronic therapy CT scan showed an increase in size of the cyst at the site of the disease recurrence. Five years and 4 months after the first operation, a new cyst exeresis and pelvic bone curettage with implant retention was performed. This case report demonstrates that hydatid cysts should be considered as a possible cause for non-specific pelvic pain, especially in endemic locations

Calculations to support JET neutron yield calibration: Modelling of neutron emission from a compact DT neutron generator

At the Joint European Torus (JET) the ex-vessel fission chambers and in-vessel activation detectors are used as the neutron production rate and neutron yield monitors respectively. In order to ensure that these detectors produce accurate measurements they need to be experimentally calibrated. A new calibration of neutron detectors to 14 MeV neutrons, resulting from deuterium–tritium (DT) plasmas, is planned at JET using a compact accelerator based neutron generator (NG) in which a D/T beam impinges on a solid target containing T/D, producing neutrons by DT fusion reactions. This paper presents the analysis that was performed to model the neutron source characteristics in terms of energy spectrum, angle–energy distribution and the effect of the neutron generator geometry. Different codes capable of simulating the accelerator based DT neutron sources are compared and sensitivities to uncertainties in the generator's internal structure analysed. The analysis was performed to support preparation to the experimental measurements performed to characterize the NG as a calibration source. Further extensive neutronics analyses, performed with this model of the NG, will be needed to support the neutron calibration experiments and take into account various differences between the calibration experiment and experiments using the plasma as a source of neutrons