^99mTechnetium scintiphotography in arthritis I. technic and interpretation

Abstract

A technic for visualization of inflamed joints using intravenously injected technetium-99m as pertechnetate and an Anger (scintillation) camera for detection will be described. Contrast between inflamed and normal tissue was usually greatest in the first few minutes after isotope injection, presumably, at the time of maximal difference in concentration of 99mTc between blood and extravascular tissue. Inflamed joints with moderate to large effusions were often visualized best 1-2 hr after injection. The extensive binding of pertechnetate by plasma and joint fluid proteins found in equilibrium dialysis experiments was evoked as an explanation of this phenomenon.Technetium-99m ("9mTc) scheme for 99M0 is given in Fig 1.4 Many clinical uses of 99mTc have been developed, including joint scans.6-7 A technic for the visualization of diseased joints using 9 s m T~ and a scintillation (Anger) camera is the subject of this report. The data are interpreted in terms of isotope kinetics. MATERIALS AND METHODSSubjects. T h e optimal time of exposure was determined after scintiphotographs of the hands and wrists of 6 patients without joint disease had demonstrated a nearly uniform distribution of radioactivity (Fig 2). The "normals" were individuals receiving intravenous pertechnetate-99m for other diagnostic studies such as brain tumor localization. The hand, "wrist" and knee joints of patients with classical rheumatoid arthritis (RA) were then examined serially. Serial frontal images (ie, patella to collimator) were obtained of an inflamed knee containing a large effusion in patient E.M.Podtfonlng. Five mc lomTc, as sodium pertechnetate (NaTcO,) , were given intravenously. The

Isotope Studies in Normal and Diseased Knee Joints: 99mTc Uptake Related to Clinical Assessment and to Synovial Perfusion Measured by the 133Xe Clearance Technique

“…The 9 9 m T~ uptake obtained in unoperated and in synovectomized patients with rheumatoid arthritis differ significantly. Assuming that the 9 9 m T~ uptake at 15 min reflects vascularity of synovium and of peri-articular tissues (McCarty et al, 1970a) these isotope studies agree with the nature of the pathology of the respective diseases. Thus it could be anticipated that a high count-rate would be found in 'inflammatory' as opposed to 'degenerative' arthritis.…”

“…Although other radioactive isotopes have been used in articular scanning studies (Danielsson, Dymling & Heripret, 1963;Fellander & Lindberg, 1966;Holopainen & Rekonen, 1966;Bauer, 1968;Kettunen & Rekonen, 1968;Bauer & Smith, 1969) radioactive technetium offers the particular advantage of low radiation hazard (Editorial, 1968 ;McCarty, Polcyn, Collins & Gottschalk, 1970a). This hazard may be reduced even further by the use of external directional counting of very low doses (c 50 pCi) as in the present study.…”

Biochemistry of articular cartilage. Nature of proteoglycans and collagen of articular cartilage and their role in ageing and in osteoarthrosis.

“…Silberberg, Silberberg, Vogel, and Wettstein (1961) monitored the fibrillar development in the joint cartilage of mice by electron microscopy. Collins, and Gottschalk (1970) found that it was albumin-bound, but we were unable to prove this ourselves. There was no evidence that drugs displaced technetium from protein binding.…”

Avoiding False‐Positive Joint Scans by the Use of Labeled Albumins

“…It appears, therefore, that the degree of joint inflammation is another factor affecting the localization of pertechnetate. McCarty et a1 (10) have reported that most joints affected by active rheumatoid arthritis were well visualized a few minutes after injection of pertechnetate. They also reported that the knee joints of some of these patients were visualized best 1-2 hours after injection.…”