ABSTRACT
A simplified scintigraphic technique for the assessment of sacroiliitis is described. It is based on the fact that an inflamed joint shows increased perfusion activity after administration of sodium pertechnetate. The sacroiliac joints are located by injection of a small amount of bone-seeking activity. Thereafter the pertechnetate activity is injected and the bone-seeking activity subtracted. The perfusion (pertechnetate) activity of the sacro-iliac joints is related to the activity of the large vessels of the thigh. Normal values have been established based on a study of 39 healthy controls. The method has been applied to 2 groups of patients with clinical sacroiliitis, one with and one without radiographical signs of sacroiliitis. The patients with radiographically verified sacroiliitis showed significantly higher values than the controls. The technique offers a high specificity and a high positive predictive value.
Subject(s)
Arthritis/diagnostic imaging , Sacroiliac Joint/diagnostic imaging , Sodium Pertechnetate Tc 99m , Adolescent , Adult , Aged , Arthritis/metabolism , Female , Humans , Male , Middle Aged , Radionuclide Imaging , Reference Values , Retrospective Studies , Sacroiliac Joint/metabolism , Sodium Pertechnetate Tc 99m/pharmacokinetics , Time FactorsABSTRACT
The thermographic appearance of the sacro-iliac joints in health and in active inflammation has been established on the basis of 72 thermographic examinations of healthy volunteers and 82 examinations of patients with clinically and radiographically active disease. In the latter group a certain number of cases showed increased heat over the sacro-iliac joints. In addition to the heat patterns described, the main conclusion of the study is a certain variability of the normal thermal pattern, a basic experience of which is necessary for the optimal interpretation of a thermogram in suspected sacro-iliitis. Despite this variability, it is possible to recognize a standard heat pattern from which most heat patterns can be derived with more or less quantitative variations. One factor affecting the thermal pattern in a fairly constant way is the amount of subcutaneous fat.
Subject(s)
Back , Sacroiliac Joint , Thermography , Adipose Tissue , Adult , Female , Hot Temperature , Humans , Inflammation/diagnosis , Inflammation/diagnostic imaging , Male , Middle Aged , Radionuclide ImagingABSTRACT
A technique for combined quantitative bone and pertechnetate (perfusion) scintigraphy of the sacro-iliac joints is described. The method is based on localization of the joints in the image obtained after the injection of a small dose of bone-seeking technetiated methyldiphosphonate. This image is later subtracted from the image obtained after the injection of pertechnetate. This combination of methods is believed to constitute a more accurate way of localizing the sacro-iliac joints than the previously used method, based on fluoroscopy. A minor comparison between these two ways of localising the joints is reported too. It is possible that the combination of quantitative bone and pertechnetate scintigraphy will improve the overall sensitivity of the scintigraphic method.
Subject(s)
Sacroiliac Joint/diagnostic imaging , Adult , Bone and Bones/diagnostic imaging , Female , Follow-Up Studies , Humans , Male , Middle Aged , Sodium Pertechnetate Tc 99m , Technetium Tc 99m Medronate , Tomography, Emission-Computed/methodsABSTRACT
Single Photon Emission Computed Tomography (SPECT) has been used to examine the spine in a prospective long-term study with the aim of assessing the value of bone scintigraphy in the detection and diagnosis of ankylosing spondylitis (AS). Sites of increased uptake of 99Tcm-MDP were observed in three of the eleven patients examined so far. By carefully optimising the SPECT system (rotating gamma camera), as well as the examination procedure, with respect to high spatial resolution, it was possible to relate these sites precisely to anatomical sites in sectional images of the spine. The advantages of SPECT are demonstrated in all three cases in which the areas of increased uptake in sagittal and transverse sections can be related to specific anatomical sites of the spine characteristically affected by AS. The findings in each of these cases are quite distinct from those of a normal case and correlate with the radiographic appearances. It is concluded that SPECT will make it easier to observe, localise and evaluate regions of increased uptake in patients with AS compared with conventional scintigraphy.
