Exporting Contours to DICOM-RT Structure Set

Subrahmanyam Gorthi,Meritxell Bach Cuadra,Jean-Philippe Thiran

doi:10.54294/yxytcv

Abstract

This paper presents an ITK implementation for exporting the contours of the automated segmentation results to DICOM-RT Structure Set format. The “radiotherapy structure set” (RTSTRUCT) object of the DICOM standard is used for the transfer of patient structures and related data, between the devices found within and outside the radiotherapy department. It mainly contains the information of regions of interest (ROIs) and points of interest (E.g. dose reference points). In many cases, rather than manually drawing these ROIs on the CT images, one can indeed benefit from the automated segmentation algorithms already implemented in ITK. But at present, it is not possible to export the ROIs obtained from ITK to RTSTRUCT format. In order to bridge this gap, we have developed a framework for exporting contour data to RTSTRUCT. We provide here the complete implementation of RTSTRUCT exporter and present the details of the pipeline used. Results on a 3-D CT image of the Head and Neck (H&N) region are presented.

Highlights

“Digital Imaging and Communications in Medicine” (DICOM) is a standard for handling, storing, printing and transmitting information in medical imaging
The purpose of the RTSTRUCT module is to address the requirements for transfer of patient structures and related data defined on CT scanners, virtual simulation workstations, treatment planning systems and similar devices
We present a brief description of each of Patient Study Series Equipment Structure Set (i) Patient (ii) General Study (iii) RT Series (iv) General Equipment (v) Structure Set (vi) regions of interest (ROIs) Contour (vii) RT ROI Observations (viii) SOP Common these modules and mention how their attributes are obtained for creating the RTSTRUCT file: 1Unlike many other DICOM modules

Summary

Introduction

“Digital Imaging and Communications in Medicine” (DICOM) is a standard for handling, storing, printing and transmitting information in medical imaging. This module primarily contains the information of the modality (“RTSTRUCT” in this case) and a series instance user ID that uniquely identifies the series. This ID is created using GDCM [3], a library used by ITK for reading and writing DICOM files. (viii) SOP Common Module: The SOP (Service-Object Pair) Common Module is mandatory for all DICOM “Information Object Definitions” (IOD) It defines the attributes which are required for proper functioning and identification of the associated SOP Instances. We present the implementation details of our RTSTRUCT-exporter

Implementation

Mask to Contour Conversion

RTSTRUCT-Exporter

Example

Conclusions & Future Work