  The lack of radiotherapy linear accelerators (LINACs) in Low- and Middle-
Income Countries (LMICs) has been recognised as a major barrier to providing
quality cancer care in these regions, along with a shortfall in the number of
highly qualified personnel. It is expected that additional challenges will be
faced in operating precise, high tech radiotherapy equipment in these
environments, and anecdotal evidence suggests that LINACs have greater downtime
and higher failure rates of components than their counterparts in High-Income
Countries. To guide future developments such as the design of a LINAC tailored
for use in LMIC environments, it is important to take a data-driven approach to
any re-engineering of the technology. However, no detailed statistical data on
LINAC downtime and failure modes has been previously collected or presented in
the literature. This work presents the first known comparative analysis of
failure modes and downtime of current generation LINACs in radiotherapy
centres, with the aim of determining any correlations between LINAC environment
and performance. Logbooks kept by radiotherapy personnel on the operation of
their LINAC were obtained and analysed from centres in Oxford (UK), Abuja,
Benin, Enugu, Lagos, Sokoto (Nigeria) and Gaborone (Botswana). By
deconstructing the LINAC into 12 different subsystems, it is found that the
vacuum subsystem only fails in the LMIC centres and the failure rate in an LMIC
environment is more than twice as large in 6 of the 12 subsystems compared to
the High Income Country (HIC). Additionally, it is shown that despite
accounting for only 3.4% of total number of faults, the LINAC faults which take
more than an hour to repair account for 74.6% of the total downtime. The
results of this study inform future attempts to mitigate the problems affecting
LINACs in LMIC environments.
