Technique of Magnetic Resonance Imaging Assisted Simulation Based on Direct Coronal Imaging for Treatment Planning of Supradiaphragmatic Malignant Lymphoma

TLDR: As imaging technology has evolved dramatically during the past two decades with the introduction of computed tomography (CT), ultrasound, digital subtraction angiography, and magnetic resonance imaging (MRI), the role of imaging has changed — becoming the most important tool in the localization procedure for malignant lymphoma nowadays.

Abstract: In radiotherapy of malignant lymphoma radiotherapy has been delivered using opposed AP/PA large fields on linear accelerators for more than 20 years (Hoppe 1987; Wannenmacher et al. 1978). A basic precondition for treatment planning has always been the adequate localization of lymphoma, lymph node bearing areas, and organs at risk, which may have to be shielded by individual blocking. The procedure of localization is performed based on clinical, pathological, and imaging information. As imaging technology has evolved dramatically during the past two decades with the introduction of computed tomography (CT), ultrasound, digital subtraction angiography, and magnetic resonance imaging (MRI), the role of imaging has changed — becoming the most important tool in the localization procedure for malignant lymphoma nowadays. Nevertheless, the most widespread basic procedure for treatment planning in malignant lymphoma remains fluoroscopic imaging on the therapy simulator (Hoppe 1987; Timothy et al. 1989; Wannenmacher et al. 1978). Tumor, target volume, and organs at risk are defined on the X-ray simulation film based on information about the localization of tumor and target which must be “translated” from transverse cross-sectional, parallel projected imaging (mostly CT) onto the centrally projected coronal X-ray images, the simulation films. This rather complicated translation procedure entails many uncertainties, in particular a considerable risk of mislocalization.