Diagnostic ultrasound-induced membrane damage in phagocytic cells loaded with contrast agent and its relation to Doppler-mode images.

Cell membrane damage induced by diagnostic ultrasound exposure with contrast agent was examined and related to the display of stimulated acoustical emission in Doppler images. Monolayers of mouse macrophage-like cells were cultured on the inside of one window of an exposure chamber. The monolayers were incubated with 5% Optison (Mallinckrodt, Inc., St. Louis, MO) for 15 minutes then rinsed to remove unattached gas bodies. A Spectra Plus scanner (Diasonics GE Medical Systems, Inc., Cincinnati, OH) in B-scan or Doppler-imaging modes exposed the chamber 3.5 cm away in a 37 degrees C water bath. The cells were scored either for uptake of fluorescent Dextran (sonoporation), or for trypan blue dye exclusion (cell death). No significant effect was seen for exposure in any mode without a contrast agent. Significant effects with contrast agent included 5.8% (2.3% standard deviation, SD) fluorescent cells and 33.4% (7.7% SD) trypan blue-stained cells in Doppler-imaging modes, compared to 0.0% and 2.2% (1.7% SD), respectively, in sham exposures. Frames of the power Doppler image were analyzed for pixel brightness to quantify the brief flash in the Doppler window. Although both membrane damage and the flash brightness increased with increasing pressure amplitude, there did not appear to be a direct correlation between the two phenomena.

Technetium-99m autologous phagocyte scanning: a new imaging technique for inflammatory bowel disease.

A method to determine the extent of active inflammatory bowel disease using selective labelling of autologous neutrophils and monocytes by phagocytosis of a technetium-99m (99mTc) stannous oxide colloid is described. Unlike leucocyte scanning techniques using Indium-III (IIIIn), the 99mTc colloid scan uses a cheap, readily available isotope, which specifically labels phagocytes. Scan results in 20 patients with inflammatory bowel disease were compared with barium examinations and colonoscopic appearances. There was close agreement in 15 of 20 patients as to the extent of mucosal disease. In four cases the scan showed more extensive disease than was suggested by barium examination. The scan showed terminal ileal Crohn's disease in three patients in whom the barium studies of the ileum had been reported as normal. In four patients with inactive disease and normal barium examinations no activity was seen on the scans. The 99mTc phagocyte scan is a sensitive, reliable means of determining the extent of active inflammatory bowel disease and can be used to quantify disease activity.

Morphological and functional findings of fixed phagocytes in psoriatics.

Twenty-one psoriatics as well as 24 normal healthy adults were studied by functional bone marrow scintigraphy using Tc-99m-labeled human serum albumin millimicrospheres (Tc-99m-HSA-MM). Functional bone marrow scintigraphy is an in vivo test system for the assessment of various functional properties of fixed phagocytes. Of psoriatics who had no systemic drug treatment, 59% demonstrated peripheral extension of the bone marrow space, indicating hyperplasia of bone marrow phagocytes. This phenomenon could be observed only in one normal subject who was a high-performance sportsman. Of psoriatics treated with aromatic retinoid, 83% (n = 6) demonstrated bone marrow extension, as did 100% (n = 3) of psoriatics with cirrhosis of liver. The "capacity' of bone marrow phagocytes to engulf Tc-99m-HSA-MM ("uptake ratio') was diminished in 34% of nontreated as well as 66% of psoriatics treated with aromatic retinoid. The phagocytic and proteolytic turnover of Tc-99m-HSA-MM in the bone marrow, spleen, and liver was found to e accelerated in 66% of nontreated psoriatics, normal (83%) or accelerated (17%) in psoriatics treated with aromatic retinoid, and considerably delayed in all of the psoriatics with cirrhosis of liver. Functional bone marrow scintigraphy proved to be an appropriate in vivo test system for revealing abnormalities of fixed phagocytes in psoriatics. Furthermore, therapeutic effects as well as the influences of preexisting disorders on different phagocyte populations can be assessed.