Estimation of patient skin dose in fluoroscopy: summary of a joint report by AAPM TG357 and EFOMP

Abstract

Background: Physicians use fixed C-arm fluoroscopy equipment with many interventional radiological and cardiological procedures. The associated effective dose to a patient is generally considered low risk, as the benefit-risk ratio is almost certainly highly favorable. However, X-ray-induced skin injuries may occur due to high absorbed patient skin doses from complex fluoroscopically guided interventions (FGI). Suitable action levels for patient-specific follow-up could improve the clinical practice.There is a need for a refined metric regarding follow-up of X-ray-induced patient injuries and the knowledge gap regarding skin dose-related patient information from fluoroscopy devices must be filled. The most useful metric to indicate a risk of erythema, epilation or greater skin injury that also includes actionable information is the peak skin dose, that is, the largest dose to a region of skin. Materials and Methods: The report is based on a comprehensive review of best practices and methods to estimate peak skin dose found in the scientific literature and situates the importance of the Digital Imaging and Communication in Medicine (DICOM) standard detailing pertinent information contained in the Radiation Dose Structured Report (RDSR) and DICOM image headers for FGI devices. Furthermore, the expertise of the task group members and consultants have been used to bridge and discuss different methods and associated available DICOM information for peak skin dose estimation.

Statement of the Italian Association of Medical Physics (AIFM) task group on radiation dose monitoring systems

“…In addition to the data obtained from the modalities, the RDMS can provide several derived dosimetric quantities, such as the effective dose, the equivalent dose to organs [ 6 ], the size specific dose estimation (SSDE) [ 21 , 22 ], the entrance dose, and the peak skin dose [ 23 – 25 ]. It can also provide patient anthropometric indicators used in dosimetric assessments such as water equivalent diameter (WED) and patient effective diameter [ 21 , 22 ].…”

AAPM Medical Physics Practice Guideline 12.a: Fluoroscopy dose management

“…The details of estimating PSD from dose indices are outside the scope of this document and have been described elsewhere. 26 , 27 Due to the various assumptions and inherent uncertainties involved, PSD estimates are unlikely to be better than ±50% accurate. 11 This uncertainty should be included in any estimate and QMPs should always include a range of possible values in addition to the likely PSD value.…”

“…PSD estimates required by policy, regulation or accreditation standard, or requested from a licensed provider, must be documented in the patient medical record. The details of estimating PSD from dose indices are outside the scope of this document and have been described elsewhere 26,27 . Due to the various assumptions and inherent uncertainties involved, PSD estimates are unlikely to be better than ±50% accurate 11 .…”

“…Radiation fields should be assumed to be overlapping unless evidence suggests otherwise. Readers are again referred to Jones and Pasciak 26 and AAPM TG 357 for more detailed discussion of performing PSD estimates 27 . In cases where radiation use did not meet recognized practice parameters, an RCA, including the QMP and members of hospital executive administration, must be performed as described by TJC 46…”

Notifications and alerts in patient dose values for computed tomography and fluoroscopy-guided interventional procedures

“…Particularly relevant are alerts for skin dose values exceeding the thresholds, to properly manage follow-up processes. Validated methods for evaluation of this metric are necessary [15,16].…”