Dose Assessment in Radiotherapy of Head and Neck Cancer after Metal Artifact Reduction in Neusoft-Philips Corporation CT Scanner: A Clinical Study

Azam  Abedini; Kourosh  Ebrahimnejad Gorji; Naser  Ghaemian; Sakineh  Soleimani Varaki; Mohammad  Davoudi; Alaba  Tolulope Agbele; Ali  Shabestani Monfared

doi:10.18502/fbt.v10i1.11510

Azam Abedini Student Research Committee, Babol University of Medical Sciences, Babol, Iran
Kourosh Ebrahimnejad Gorji Department of Medical Physics Radiobiology and Radiation Protection, School of Medicine, Babol University of Medical Sciences, Babol, Iran
Naser Ghaemian Department of Pediatric Radiology, Babol University of Medical Sciences, Babol, Iran
Sakineh Soleimani Varaki Radiation Oncologist, Babol University of Medical Sciences, Babol, Iran
Mohammad Davoudi Department of Medical Imaging Center, Babol University of Medical Sciences, Babol, Iran
Alaba Tolulope Agbele Department of Medical Physics, Tehran University of Medical Sciences, Tehran, Iran
Ali Shabestani Monfared Cancer Research Center, Health Research Institute, Babol University of Medical Sciences, Babol, Iran

DOI: https://doi.org/10.18502/fbt.v10i1.11510

Keywords: Computed Tomography; Radiotherapy; Metal Artifacts; Head and Neck Tumors; Dose.

Abstract

Purpose: Metal artifacts cause to increase in the uncorrected dose evaluation during radiotherapy planning. This study aimed to evaluate the probable difference of the dose parameters calculated by the Treatment Planning System (TPS) in radiotherapy of head and neck cancer before and after metal artifact correction in Neusoft-Philips Corporation Computed Tomography (CT) images.

Materials and Methods: In the present study, the radiotherapy planning of the head and neck cancer from thirty patients was first performed on the CT default images with dental implants. The same processes were applied after performing a body standard metal kernel on the CT images to reduce the metal artifacts. The Gross Tumor Volume (GTV) and Organ At Risks (OARs) were contoured on the CT slices. The dosimetric parameters (mean, minimum, and maximum) for the GTV and OARs (eyes and spinal cord) were obtained for both sets of CT images (defaults and filtered). Wilcoxon signed-rank test was used to calculate the probability dose variations between the two sets.

Results: There are significant differences in several dose parameters between the default and filtered CT images (P-value < 0.05). These dosimetric parameters are related to the GTV (mean dose), spinal cord (minimum and mean doses), right eye (maximum dose), as well as left eye (mean dose). The average range of dose differences between the default and filtered images was obtained; 1.12%-3.11% for the GTV as well as 0.22%-12.05% for the OARs.

Conclusion: Based on the results, the body standard metal kernel can cause a significant difference in several dosimetric parameters of GTV and OARs during the radiotherapy of head and neck cancer. Therefore, it is recommended to make a metal artifact correction on CT images for accurate dose calculation before designing a treatment plan.