Radiopacity of tantalum-loaded acrylic bone cement

Abstract

Radiopacifying agents are commonly added to bone cements to enhance the visibility of the cement in radiography. The radiopacifiers usually employed may, however, have undesired effects on the mechanical properties of the cement. A potentially new radiopacifier is tantalum, which in the present work was evaluated in terms of radiopacity. Bone cements containing different percentages of tantalum were compared with plain bone cement as well as with formulations containing different percentages of the commonly used radiopacifier barium sulphate. The radiopacity was assessed quantitatively and qualitatively, by measuring with a digital densitometer the optical density of the cement on X-ray films, and consulting the expertise of ten orthopaedic surgeons. It was found that tantalum does present radiopacity, but not as high as barium sulphate under the specific conditions applied to this study.

A Review of PMMA Bone Cement and Intra-Cardiac Embolism

“…Unfortunately, some detrimental effects of these radiopaque agents on the mechanical behavior of PMMA have been observed [61]. Hernandez et al showed that a PMMA cement with 10% w/w barium sulfate has a similar viscosity-time curve but a much earlier onset of viscosity rise compared to the same cement with no radiopacifier [62]. This highlights the effect of varying the radiopacifier composition on the viscosity of the cement, thus the injection behavior of that cement suspension.…”

Calcium phosphate cements with strontium halides as radiopacifiers

“…It is known from the literature that the radiopacity is also related to the K-edge transition energy of the elements contained in the material as well as the energy applied: a maximum attenuation is achieved when the energy of the X-rays matches the K-edge transition energy; in addition, most X-rays have an energy between 1/3-1/2 of the applied voltage. 8 The elements bromide, strontium, zirconium, iodine, and barium have K-edge energies of 13.5, 16.1, 18.0, 33.2, and 37.5 keV, respectively, whereas the applied peak voltage was 72 keV, which is a typical peak voltage used in clinics. The attenuating effect of an element decreases substantially with the applied voltage right before and right after the K-edge transition energy, which explains the variability in the radiopacity.…”

“…In addition, a higher radiopacity is also expected when the K-edge transition energy of the element matches 1/3-1/2 of the applied peak kilovoltage. 8 The ASTM F640 standard 9 suggests methods to measure the radiopacity of a material for medical applications. Materials that do not have enough intrinsic radiopacity, for example, acrylic bone cements, are normally modified with inorganic radiopaque agents to improve their radiopacity.…”

Cement leakage in a symptomatic vertebral hemangioma: a case report and review of the literature

“…Nevertheless, for some authors this technique has not been helpful with regard to the prevention of cement spillage and therefore has been abandoned [11]. Since nowadays vertebroplasty has become a widespread technique, several other methods have been proposed for minimizing the risk of cement leakage: the use of tantalum-impregnated polymethylmethacrylate in very small (2-cc) amounts [12], the use of cement in a doughy rather than liquid consistency [13], injection with minimal-constant pressure [14], the placement of large needles well anteriorly into the vertebral body through both pedicles and finally the new technique of balloon kyphoplasty [15] which effectively prevents posterior extrusion of cement while allowing at the same time some expansion of the collapsed vertebra.…”