Quality control in cone-beam computed tomography (CBCT) EFOMP-ESTRO-IAEA protocol (summary report)

Abstract

The aim of the guideline presented in this article is to unify the test parameters for image quality evaluation and radiation output in all types of cone-beam computed tomography (CBCT) systems. The applications of CBCT spread over dental and interventional radiology, guided surgery and radiotherapy. The chosen tests provide the means to objectively evaluate the performance and monitor the constancy of the imaging chain. Experience from all involved associations has been collected to achieve a consensus that is rigorous and helpful for the practice. The guideline recommends to assess image quality in terms of uniformity, geometrical precision, voxel density values (or Hounsfield units where available), noise, low contrast resolution and spatial resolution measurements. These tests usually require the use of a phantom and evaluation software. Radiation output can be determined with a kerma-area product meter attached to the tube case. Alternatively, a solid state dosimeter attached to the flat panel and a simple geometric relationship can be used to calculate the dose to the isocentre. Summary tables including action levels and recommended frequencies for each test, as well as relevant references, are provided. If the radiation output or image quality deviates from expected values, or exceeds documented action levels for a given system, a more in depth system analysis (using conventional tests) and corrective maintenance work may be required.

An overview of deep learning in the field of dentistry

“…For example, collecting and learning data on a machine-by-machine basis is difficult because models learned on one machine do not apply to other machines. Although attempts have been made to develop guidelines in Europe, Germany, and England regarding the image quality of CBCT, no international standard has yet been established 41. Therefore, in order for 3-dimensional diagnosis using deep learning to be practical, an international standard for the quality of CBCT images needs to be established in the near future.…”

Correlation of objective image quality and working length measurements in different CBCT machines: An ex vivo study

“…Obviously, a clinician will expect high-quality images when deriving treatment plans or diagnosis from them. From a technical perspective, CBCT image quality can be determined using objective image quality parameters such as noise, contrast and spatial resolution 14,15 . Since MTF relates spatial resolution to contrast and CNR provides a good estimate of the noise level, the image quality parameters used for this study should sufficiently summarize the objective quality of the CBCT images.…”

“…These different characteristics affect image quality, dose ranges 13 and probably the interpretation of the images as well. The latter is the reason why quality control standards or CBCT have been set up 14 or suggested by expert groups 15 . On the other hand, it is not an effortless task to establish a direct link between objective image quality and a specific diagnostic task.…”

Cumulative Inaccuracies in Implementation of Additive Manufacturing Through Medical Imaging, 3D Thresholding, and 3D Modeling: A Case Study for an End-Use Implant

“…To this end, it differs from the conventional manufacturing methodologies, i.e., subtractive and formative manufacturing. AM has been widely implemented in the medical industry [4], and it has gained clearance for more than 80 AM medical devices such as maxillofacial implants and a knee joint systems [40], the QA program proposed by the SEDENTEXCT Project [41], and the EFOMP CBCT QA Protocol [42]. The standardized QA Phantoms including the European project-based [41], commercial [43], and low-cost alternatives [44] enable the assessment of accuracy and quality of the CT systems [40].…”