technetium-tc-99m-exametazime and Foot-Diseases

This article provides a brief overview of the current state of hybrid single-photon emission computed tomography/computer tomography (SPECT/CT) imaging in musculoskeletal infections. SPECT/CT imaging, compared with conventional planar study and SPECT alone, provides improved anatomic localization of infection and more accurate delineation of the extent of infection. This article emphasizes three clinical aspects where SPECT/CT is found to be most useful: differentiating between soft tissue and bone infections, assessing suspected infected sites with underlying structural bone alterations, and defining infective focus when complex anatomy is involved. The accurate assessment of site of infection is vital for selecting the most appropriate therapeutic strategy. Other advantages of SPECT/CT imaging such as reducing the inconvenience of combination planar studies, providing additional CT information, and increasing interobserver agreement are also discussed.

Topics: Bone Diseases; Child; Foot Diseases; Gallium Radioisotopes; Humans; Indium Radioisotopes; Infections; Musculoskeletal Diseases; Postoperative Complications; Soft Tissue Infections; Spinal Diseases; Technetium Tc 99m Exametazime; Technetium Tc 99m Medronate; Tomography, Emission-Computed, Single-Photon; Tomography, X-Ray Computed; Wounds and Injuries

Liposomes are phospholipid nanoparticles used for targeted drug delivery. This study aimed to determine whether intravenous liposomes accumulate in lamellar tissue during laminitis development in horses so as to assess their potential for targeted lamellar drug delivery. Polyethylene-glycol (PEG) coated liposomes were prepared according to the film hydration method and labelled using (99m)Tc-hexamethyl-propylene-amine-oxime. Six horses received 10 g/kg oligofructose via nasogastric tube to induce laminitis, and four control horses received water via nasogastric tube. All horses received 300 µmol (99m)Tc-PEG-liposomes (5.5 GBq) plus 5.5 µmol/kg PEG-liposomes by slow intravenous infusion. Scintigraphic imaging was performed at 0, 6 and 12 h post-infusion. Technetium-99m liposome uptake was measured in regions of interest over the hoof, fetlock and metacarpus. At the study end-point horses were euthanased, tissue samples collected and tissue liposome levels were calculated as the percentage of the injected dose of (99m)Tc-liposomes per kilogram of tissue. Data were analysed non-parametrically. All horses receiving oligofructose developed clinical and histological signs of laminitis. Technetium-99m liposome uptake in the hoof increased with time in laminitis horses (P = 0.04), but decreased with time in control horses (P = 0.01). Technetium-99m liposome levels in lamellar tissue from laminitis horses were 3.2-fold higher than controls (P = 0.02) and were also higher in laminitis vs. control skin, muscle, jejunum, colon, and kidney (P < 0.05). Liposomes accumulated in lamellar tissue during oligofructose-induced laminitis development and demonstrated potential for targeted lamellar drug delivery in acute laminitis. This study provides further evidence that lamellar inflammation occurs during laminitis development. Liposome accumulation also occurred in the skin, muscle, jejunum, colon and kidneys, suggesting systemic inflammation in this model.

Topics: Animals; Foot Diseases; Hoof and Claw; Horse Diseases; Horses; Inflammation; Liposomes; Male; Oligosaccharides; Polyethylene Glycols; Radiopharmaceuticals; Technetium Tc 99m Exametazime

Early diagnosis of osteomyelitis is helpful for a successful conservative treatment. The value of bone scanning combined with granulocytes labeled with hexamethylpropylene amine oxime (HMPAO) granulocyte-Tc99m (GN) radionuclide imaging (combined [RI]) with magnetic resonance imaging (MRI) for the diagnosis of osteomyelitis was assessed in 24 diabetic patients with foot ulcers. Evidence of osteomyelitis was based on the presence of at least one of the following criteria: (1) clinical bone involvement, (2) radiological bone involvement, (3) both positive combined RI and MRI, and (4) evidence of clinical bone involvement during the follow-up period. Thirteen patients had osteomyelitis. Seven patients had clinical bone involvement (sensitivity, 54%), five had radiological bone involvement (sensitivity, 38%), and 10 had positive combined RI for osteomyelitis (sensitivity, 77%). MRI demonstrated a higher sensitivity (100%). The specificity for combined RI and MRI was 82%. These results lead to a new diagnostic strategy for the early detection of minimal or localized osteomyelitis to avoid amputations. MRI is most appropriate following a negative x-ray in determining whether to treat osteomyelitis, since a negative MRI result rules out osteomyelitis. Antibiotic therapy should be used in the case of a positive MRI result, but Charcot joint disease can lead to false-positive MRI results. In this case, combined RI should be performed.

Topics: Aged; Bone Marrow; Diabetes Complications; Female; Foot Diseases; Humans; Magnetic Resonance Imaging; Male; Middle Aged; Osteomyelitis; Radionuclide Imaging; Radiopharmaceuticals; Sensitivity and Specificity; Technetium Tc 99m Exametazime; Time Factors; Treatment Outcome

Topics: Adult; Bacterial Infections; Foot Diseases; Humans; Leukocytes; Lymph Nodes; Male; Middle Aged; Organotechnetium Compounds; Oximes; Radionuclide Imaging; Technetium Tc 99m Exametazime

Topics: Animals; Female; Foot Diseases; Horse Diseases; Horses; Lameness, Animal; Leukocytes; Male; Organotechnetium Compounds; Oximes; Pilot Projects; Radionuclide Imaging; Sepsis; Technetium Tc 99m Exametazime; Tendinopathy