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Purpose: Technological advancements of Radiation Therapy included IMRT and VMAT. Treatment technologies that are utilizing a huge amount of small field contributions to deliver highly complex, conformal, organ at risk sparing radiation treatments. In the same time the technical ability to perform a considerable range of stereotactic treatments with a Linear Accelerator was established and adopted in many clinics. Small field dosimetry traditionally is the dosimetry discipline with the closest relation of physical properties of radiation and particles and interactions with matter. Detector choice has always been crucial for reliable small field dosimetry, and the best detector is still to be found.

Methods: Following the structure of Radiochromic film dosimetry Recommendations of AAPM Radiation Therapy Committee Task Group 55 the current status of Gafchromic EBT-x dosimetry is reviewed. Furthermore the question is discussed whether improvements in Gafchromic film dosimetry methods of the last years have changed the role of film in small film dosimetry.

Results: Within a lunch breaks time a set of smallest field 2D dose distributions can be acquired with Gafchromic EBT3 film in impressive high detail and resolution with or without commercially available software. Fig. 1 and Fig. 2 give an example, solely utilizing the red color channel without advanced artifact correction algorithms. Absolute dose readings fit in uncertainty ranges published for point based detectors.

Conclusion: Technology advancements in IMRT/VMAT/SBRT/SRS planning and delivery contribute to increasing importance of small field dosimetry. Radiochromic film has a very high spatial resolution and absolute dose measurement capability. New techniques of evaluation overcome the artifacts commonly associated with Radiochromic film dosimetry. A protocol for Radiochromic film based general small field dosimetry or an update on existing recommendations is desirable as basis of feasible results obtained in clinical dosimetry.