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Purpose: To evaluate the in vitro stability of tris-acryl gelatin microspheres (TAGMs) in a multipharmaceutical solution as a preliminary step before planned hepatic chemoembolization with TAGMs., Materials and Methods: Half-cm(3) aliquots of 100-300- micro m and 300-500- micro m TAGMs were suspended in 1 mL of normal saline solution (NSS), 1 mL of ethiodized oil, or 1 mL of a standard chemoembolization solution (cisplatin 100 mg, doxorubicin 50 mg, mitomycin 10 mg, ethiodized oil 3 mL, and iodixanol 5 mL). Mixtures were incubated at 37 degrees C for 24 hours and were then examined visually and with use of light microscopy. Solutions containing ethiodized oil required centrifugation for separation. Determination of average sphere diameter after 24-hour chemoembolization incubation was performed after washing in ethanol, washing in acetone, and rinsing in 0.9% aqueous sodium chloride solution., Results: TAGMs in NSS had no gross degradation, were intact on light microscopy, and had no visually perceptible change in average diameter. TAGMs in ethiodized oil alone appeared to dissolve into a cloudy solution; however, centrifugation separated spheres from ethiodized oil as a layer, which was intact on light microscopy. Spheres incubated in the chemoembolization solution were not grossly visible as a result of the deep red color of doxorubicin (which stained the spheres), but were easily seen after centrifugation. There were similar numbers of spheres per field on microscopy with a minimal (but significant) increase in analyzed diameter., Conclusion: TAGMs are stable in a standard chemoembolization solution and may be suitable as a substitute for PVA particles in hepatic chemoembolization.

Purpose: To evaluate the utility of low-dose irradiation as adjunctive treatment for failing dialysis shunts related to stenoses., Materials and Methods: Thirty-one patients with 41 lesions in their dialysis shunts were successfully enrolled for this study. After imaging of the shunt and calculation of venous stenoses, each patient was randomized into one of two segments of the protocol: (i) angioplasty and/or stent placement alone, and (ii) angioplasty and/or stent placement followed by external beam irradiation. All patients with significant venous stenoses (> or =50%) were treated with appropriately sized PTA (percutaneous transluminal angioplasty) and Wallstents. Patients randomized to the external irradiation segment underwent localized irradiation via a Theratron cobalt unit of 7 Gy 0-24 hours and 24-48 hours after intervention. Those patients randomized to the control group received no additional treatment. Clinical follow-up included resumption of successful dialysis with appropriate hemodynamic parameters. Two follow-up shunt images were obtained, follow-up 1 (fu-1) from 90 to 179 days and follow-up 2 (fu-2) from 180 to 365 days. Percentages of significant recurrent stenoses, defined as greater than 50%, were recorded and re-treated as needed., Results: Sixteen of the 31 patients underwent external beam irradiation. There were 21 lesions in the test group that underwent irradiation after intervention, and 20 lesions were treated with intervention alone. There were seven native arteriovenous fistulas and 24 Gore-tex grafts. All stenoses were either venous outflow stenoses (68%) or central stenoses (32%). The authors utilized chi2 analysis to compare restenoses rates between the control and irradiated groups at fu-1 (P<.99) and fu-2 (P<.10)., Conclusions: Although the results show that external beam irradiation has minimal effects on the restenoses of dialysis grafts when used in conjunction with PTA and stent placement, further studies with a larger, more homogenous population are needed to assess the trend of improving patency rates after external beam irradiation.