CPT® Code 77331

The CPT® Code 77331 refers to the process of special dosimetry, which is a specialized method used to measure and report the radiation dose at a specific point within a treatment port. This point is typically outside the standard calculational parameters established by the treatment planning system or the calibration of the treatment device. Special dosimetry is crucial in ensuring that the radiation delivered during treatment is accurately monitored, particularly in areas where conventional methods may not provide sufficient data. The procedure may utilize various advanced techniques, including thermoluminescent dosimetry (TLD), solid-state diode probes, or other specialized dosimetry probes. The results obtained from this study are essential for the radiation oncologist or qualified medical professional to assess the effectiveness of the current treatment plan. The treating physician must provide a detailed request for special dosimetry, which includes a clear statement of the necessity for the study and an explanation of how the findings are anticipated to influence the ongoing treatment strategy.