The role of Cobalt-60 in modern radiation therapy: Dose delivery and image guidance

Abstract

The advances in modern radiation therapy with techniques such as intensity-modulated radiation therapy and image-guided radiation therapy (IMRT and IGRT) have been limited almost exclusively to linear accelerators. Investigations of modern Cobalt-60 (Co-60) radiation delivery in the context of IMRT and IGRT have been very sparse, and have been limited mainly to computer-modeling and treatment-planning exercises. In this paper, we report on the results of experiments using a tomotherapy benchtop apparatus attached to a conventional Co-60 unit. We show that conformal dose delivery is possible and also that Co-60 can be used as the radiation source in megavoltage computed tomography imaging. These results complement our modeling studies of Co-60 tomotherapy and provide a strong motivation for continuing development of modern Cobalt-60 treatment devices.

Experiments in unmanned aerial vehicle/unmanned ground vehicle radiation search

“…2.59 MBq of cobalt‐60 was placed at Location . Cobalt‐60 is an isotope with industrial (Barbour, ), medical radiotherapy (Schreiner et al, ), and food irradiation (Bhat et al, ), applications, among many others. Cobalt‐60 is man‐made isotope; therefore, it represents a threat source that should be distinct from background radiation.…”

Monte Carlo simulation based study of a proposed multileaf collimator for a telecobalt machine

“…Accordingly, 34 central and 2 peripheral leaf pairs with projected leaf width of 1 and 0.5 cm, respectively, were chosen. It was also assumed that the MLC leaves were made up of tungsten alloy of density 18.5 g/cm 3 . The nomenclature recommended in AAPM Report No.…”

“…For example, commercial telecobalt machine is yet to be augmented with a multileaf col-limator (MLC), which is a necessary element for efficient delivery of conventional three-dimensional conformal radiation therapy (3D-CRT) and a basic requirement for the implementation of intensity modulated radiation therapy (IMRT). 2,3 As a result, by the 1990s telecobalt based EXBT had fallen from favor in the developed countries like the United States. 1,4 A few investigators have carried out feasibility studies toward modernizing telecobalt machine as a tomotherapy device.…”

“…1,4 A few investigators have carried out feasibility studies toward modernizing telecobalt machine as a tomotherapy device. 2,3,5 Joshi et al 2 investigated tomotherapy dose distributions for two clinical cases by comparing 60 Co based tomotherapy and a 6 MV linac based tomotherapy. They demonstrated that 60 Co based tomotherapy dose distributions were comparable to 6 MV linac based tomotherapy.…”

“…They demonstrated that 60 Co based tomotherapy dose distributions were comparable to 6 MV linac based tomotherapy. Schreiner et al 3 reported that telecobalt machine can be used as an image guided radiation therapy (IGRT) device. Adams and Warrington 6 executed conformal radiation therapy and IMRT treatment plans created for 60 Co using blocks and compensators for a range of treatment sites and compared them with those created using 6/10 MV photons with a MLC.…”