Authors’ reply to 'Dosimetric of intracranial stereotactic radiosurgery: only ‘an exercise of style’'

We thank Dr. Fiorentino and colleagues for their interest in our article comparing dosimetric treatment plan quality in intracranial stereotactic radiosurgery (SRS) [12]. The purpose of our study was to test whether robotic radiosurgery can create at least equivalent treatment plans when compared to classical SRS with a linear accelerator (linac-SRS). Linac-SRS with conical collimators or a micro-multileaf collimator is widely used and a well-established clinical standard for the treatment of small intracranial target volumes [7, 10]. Treatment plan comparisons allow, if they are carried out properly, reliable statements to be made about the clinical utility of a new irradiation method or new radiation device [9]. Since plan comparisons can generally be carried out using a matched pair analysis, the required number of cases investigated can be kept low. Usually about 10 cases (range 1–15) are used in the literature [1, 3, 5, 6, 8, 9]. Vice versa, methodological requirements for meaningful plan