Dosimetric Validation of Scans Generated by GAN From Pre-therapeutic MRI in Stereotactic Cerebral Radiotherapy

Dosimetric Validation of Scans Generated by GAN From Pre-therapeutic MRI in Stereotactic Cerebral Radiotherapy (SBRT-IRM)

Stereotactic radiotherapy (SRT) is being widely accepted as a treatment of choice for patients with a small number of brain metastases and an acceptable size, allowing a better target dose conformity resulting in high local control rates and better sparing of organs at risk. Currently, imaging for such a delivery technique requires both a recent magnetic resonance imaging (MRI) brain study for volume definition and a computed tomography (CT) scan for SRT planning. An MRI-only workflow could reduce the risk of misalignment between the two imaging modalities and shorten the delay of planning. Given the absence of a calibrated electronic density on MRI, the investigators aim to assess the equivalence of synthetic CTs generated by a generative adversarial network (GAN) for planning in the brain SRT setting.

Inclusion Criteria:

• age ≥ 18 years old
• SRT treatment for one or more brain metastasis(ses)
• brain MRI and planning CT scans realized less than 14 days prior to the treatment delivery

Exclusion Criteria:

• MRI's field of view (FOV) judged insufficient for tumour(s) and OAR visualization