Abstract:
Purpose: This study investigates the influence of blood perfusion variability within a tumour and
the surrounding healthy tissue during nanoparticle-assisted thermal therapy. It seeks to define
ideal therapeutic parameters for a wide range of perfusion rates to attain the desired thermal
damage. Material and methods: Pennes’ bioheat model and the Arrhenius model are used
to evaluate the thermal damage for a two-dimensional tumour surrounded by healthy tissue.
A wide range of tumour perfusion rates were modelled, ranging from moderate to high
perfusion in both a homogenously and a heterogeneously perfused tumour. Results: For low
perfusion rates, a temporal variation in blood perfusion does not critically influence the thermal
damage. For moderately and highly perfused tumours, temporal variation in blood perfusion
extends the thermal damage zone by 25–52% compared to a constant perfusion rate. For the
tumour size and perfusion conditions under consideration, the ideal therapeutic parameters
were found to be irradiation intensity of 1 W/cm2
, and irradiation duration of 105–150 s, for
a nanoparticle volume fraction of 0.001%. Conclusions: It is concluded for low perfusion rates
that due to shorter therapeutic duration, nanoparticle-assisted thermal therapy is relatively
insensitive to changes in the perfusion rate during the therapy. For moderately and highly
perfused tumours, a constant perfusion under-predicts the real thermal damage zone.
This study concludes that for moderately and highly perfused tumours the spatial as well as
temporal blood perfusion dynamics should be carefully accounted for to get a realistic estimate
of thermal damage zone.
