Patient Data Privacy in ORUse Framework

Bachelor IDP by: Kristina Bayer und Peter Maximilian Hirschbeck
Advisor: Prof. Nassir Navab
Supervision by: Asli Okur
Due date: 2012/07/01

Abstract

In clinical studies, there is an overload of medical data, which needs to be treated cautiously due to patient data privacy issues. Although the patients sign documents to confirm that the medical/personal data related to their disease might be distributed to 3rd persons such as different departments of the hospital, it still needs to made sure that the critical parts are at least pseudo-anonymized, meaning that at least the names are kept secret and only the responsible physicians for the study can map the names to the study IDs of the patients for quality assurance.

In Klinikum rechts der Isar, TU München, there is currently a clinical study started called "SLN3D", where the nuclear medicine, gynecology departments from the medical side and the CAMP chair from the technical side are involved in. In this study, 150 patients are planned to be recruited, where the Freehand SPECT (fhSPECT) system developed by the CAMP chair and the company SurgicEye GmbH is to be used intraoperatively in SLNB procedures of breast cancer patients. For this study, the medical data such as preoperative nuclear imaging like SPECT/CT, scintigraphy and fhSPECT are to be saved in addition to the intraoperative fhSPECT. All of these different modalities have different format and characteristics, which should be analyzed and investigated for proper anonymization and saving. In case of preoperative fhSPECT, the screenshots generated by the system even involves the faces of the patients, which needs to be considered, as well.

For evaluation of intra-operative imaging devices, an extensible and flexible data gathering and evaluation framework called ORUse has been developed in the CAMP chair. The first device modeled in this framework is the Freehand SPECT system, which is mentioned above. Until now, only the automatic output of the Freehand SPECT system is included in the model, with no effect of patient characteristics and additional available information. However, involving the preoperative data inside the framework would provide a great platform for further investigations such as to analyze the surgeries based on different parameters much faster and more intuitively. In order to do this, the data should be pseudo-anonymized beforehand.

The goal of this interdisciplinary project is to develop an application, which will be used later for fast (pseudo-)anonymization of multiple acquisitions involving different modalities, datatypes or requirements such as scintigraphy, SPECT/CT and Freehand SPECT by the study investigators. The programming environment will be C# and Visual Studio. This tool then will be used to upload and integrate the preoperative medical imaging data inside the ORUse framework.

Project Outline

1. Introduction

• Getting familiar with the DICOM standard and medical data
• Getting familiar with C# and Visual Studio
• Analysis of available 3rd-party DICOM libraries for C#
• Analysis of the provided data and tags by different devices for critical parts for patient data privacy (e.g. name)
• Attending several surgeries in Klinikum rechts der Isar with Freehand SPECT system

2. Implementation

• (Pseudo-)Anonymization of the DICOM Tags of the imaging data based on the description in ethics documents of the clinical study "SLN3D"
• Display of the DICOM slices inside the application as graphic objects
• Removal of hard-coded names from the summary scintigraphy images (DICOM)
• Auto suggestion of the place of the hard-coded name based on the used device (readable from the DICOM-Tags)
• XML-based initialization and configuration
• Blurring of patient faces in sequential screenshots of pre-operative Freehand SPECT data

3. Evaluation

• Testing the tool with experimental data
• Anonymization of 10 real patient data using the developed tool

4. Documentation and Presentation