technetium-tc-99m-medronate and Foreign-Body-Reaction

Necrotic pseudotumor is a complication of metal-on-metal arthroplasty that has been reported with increasing frequency in the last 5 years. It is believed to be the result of a hypersensitivity reaction to metal ions such as nickel, cobalt, or chromium that are released in large quantities from these prostheses. The imaging appearance of a necrotic pseudotumor caused by a metal-on-metal prosthesis, on (18)F-FDG PET/CT or (99m)Tc-MDP bone scan has not been previously described in the literature. Our case demonstrates that a necrotic pseudotumor can be detected incidentally in oncologic patients referred for an (18)F-FDG PET/CT or a (99m)Tc-MDP bone scan, and recognizing this process is vital in preventing further tissue necrosis and patient morbidity, as the offending prosthesis must be promptly removed. The imaging characteristics of a necrotic pseudotumor on PET/CT and bone scan may also mimic a malignant process such as a necrotic sarcoma, and can represent a potential pitfall leading to a false positive diagnosis in an oncologic patient.

Topics: Aged, 80 and over; Arthroplasty, Replacement, Hip; Diagnosis, Differential; Female; Fluorodeoxyglucose F18; Foreign-Body Reaction; Hip Prosthesis; Humans; Metals; Necrosis; Positron-Emission Tomography; Radiopharmaceuticals; Technetium Tc 99m Medronate; Tomography, X-Ray Computed

Topics: Adult; Female; Finger Injuries; Foreign-Body Reaction; Humans; Plant Structures; Punctures; Radionuclide Imaging; Radiopharmaceuticals; Technetium Tc 99m Medronate; Tenosynovitis; Wounds, Penetrating

This paper aims to present the usefulness of the different diagnosis imaging methods (anatomical and functional) in the characterization of bone injury. Any data, however insignificant, is justified and should be specified. In this case, the discrepancy between the vascular and pool phases in the bone scintigraphy with 99mTc-MDP reveals revealed a lesion with an intense reaction secondary to the "foreign body effect", which is not necessarily malignant.

Topics: Adolescent; Diagnosis, Differential; Femoral Neoplasms; Foreign-Body Reaction; Humans; Magnetic Resonance Imaging; Osteoma, Osteoid; Radionuclide Imaging; Radiopharmaceuticals; Technetium Tc 99m Medronate

Three patients with total knee arthroplasties, in which the tibial and patellar articulating surfaces consisted of a polyethylene-carbon fiber composite, demonstrated technetium-99m methylene diphosphonate (MDP) deposition in the intraarticular space, whereas, the gallium-67 citrate images were normal. This was shown to be due to a synovial giant cell foreign body reaction to particulate carbon fiber debris in one patient who required surgical revision of the prosthesis.

Topics: Adult; Aged; Carbon; Carbon Fiber; Female; Foreign-Body Reaction; Gallium Radioisotopes; Humans; Knee Prosthesis; Male; Middle Aged; Plastics; Polyethylenes; Radionuclide Imaging; Technetium Tc 99m Medronate