Summer Course in Medical Physics 2024 IndoQCT and IndoseCT for CT Image Quality and Dosimetry Measurements

IndoseCT is software to calculate and manage the radiation dose of a patient undergoing CT examination. It does not only calculate the radiation output dose of CT machines (in terms of CTDIvol), but also the individual dose received by each patient (in terms of SSDE) either based on the effective diameter (Deff) or water-equivalent diameter (Dw). This software can also calculate radiation output and patient dose for CT equipped with TCM technique. IndoseCT has been recorded in the Letter of Registration of Creation, Ministry of Law and Human Rights (Kementerian Hukum dan HAM), Republic of Indonesia, Number 000217029, on August 12, 2020.

Until 2011, CT doses had been characterized by the CTDIvol, whereas that metric is only able to quantify CT radiation output. The CTDIvol value is influenced by almost all input parameters, such as tube voltage (kVp), tube current (mA), rotation time (s), pitch, collimation width, and others. It was noted, since its introduction, that CTDIvol was not meant to indicate the radiation dose received by the patient. This is because the dose within each scanner is influenced by not only the radiation output from the CT machine but also by the characteristics of the patient undergoing the examination, such as the size of the patient and the composition of the body part being examined. To quantify a patient’s radiation dose, a new metric of SSDE was introduced.

IndoseCT software estimates the radiation dose directly for each patient using the patient’s image or by entering patient data manually. IndoseCT can also be used for the estimation of organ dose and effective dose. The effective dose is the dose commonly used to estimate the risk of developing cancer in the future from CT examinations. IndoseCT is also equipped with tools to store patient dosimetry data in a database. From this database, the software can analyze patient dosimetry data and easily display its graphs so that it becomes useful information for dose optimization for the use of ionizing radiation for stakeholders, whether for medical physicists, radiology doctors, hospital management, or regulatory agencies.

About  IndoQCT

IndoQCT is software for automatically measuring CT image quality. IndoQCT can measure many CT quality parameters (either manually or automatically), including CT number (accuracy, uniformity, homogeneity, and linearity), image noise (tolerance, uniformity, and NPS), spatial resolution (visual, MTF based on point, MTF based on edge, and TTF), slice thickness, low-contrast resolution (visual, contrast-to noiseration (CNR), LCD statistical calculations), CT alignment, gantry tilt, distance accuracy, and distance between slice accuracy. IndoQCT can measure CT quality parameters from several types of phantoms available in the market, such as AAPM CT performance phantom, ACR CT accreditation phantom, CatPhan phantom, and phantoms supplied by CT vendors (GE, Siemens, Philips, and Toshiba). Moreover, several CT quality parameters can be measured directly from patient clinical images, such as CT number, image noise, LCD, spatial resolution, and alignment.