Wyniki wyszukiwania - BazTech

Ograniczanie wyników

2 Polish Journal of Medical Physics and Engineering

Powiadomienia systemowe

Sesja wygasła!

Znaleziono wyników: 2

Liczba wyników na stronie

Wyniki wyszukiwania

Wyszukiwano:
w słowach kluczowych: computed tomography dose index

Sortuj według:

Ogranicz wyniki do:

Assessment of Radiation Doses for Paediatric Head, Chest, and Abdominopelvic Computed Tomography Examinations in a Teaching Hospital in Ghana

Amedzoame Bernard, Brobbey Isaac Frimpong, Djan Bismark, Acquah Isaac Kwesi, Tetteh Mercy Afadzi

Polish Journal of Medical Physics and Engineering

2025

Vol. 31, Iss. 3

256--262

Introduction: With the increasing number of pediatric computed tomography (CT) examinations, there is a need to optimise protocols for children by adopting examination-specific protocols customised to the patient’s age, size, imaging region, and clinical indication. This study aimed to assess the radiation doses in pediatric CT examinations and compare them to international standards. Material and methods: A cross-sectional retrospective study design was adopted to probe patient records at the radiology department of a teaching hospital in Ghana. Thus, scan parameters, volume computed tomography dose index (CTDIvol), dose length product (DLP), as well as demographic data, were recorded from 496 pediatric patients (age 0-15 years) undergoing head, chest, and abdominopelvic CT examinations. Local Diagnostic Reference Levels (LDRLs) were established using the 75th percentile of patient dose values for each protocol and age group. These local levels were then compared with DRLs from other studies. Results: Head CT was the most performed examination (35.0%) compared to chest (32.0%) and abdominopelvic (33.0%). The male group recorded the highest (59.1%) percentage of CT examinations compared to the female group. While LDRL values from this study were generally lower than data from other studies, the CTDIvol and DLP for head scans of patients between 11 and 15 years were found to be higher than the data from other studies. Conclusions: Our study has established LDRLs for standard pediatric CT examinations in the teaching hospital. The LDRLs were generally lower than those reported in other studies, except for head scans in patients aged 11 to 15 years. These findings suggest that there are opportunities for further optimisation of pediatric CT imaging protocols at this facility.

Effective and organ doses from common CT examinations in one general hospital in Tehran, Iran

Khoramian D., Hashemi B.

Polish Journal of Medical Physics and Engineering

2017

Vol. 23, Iss. 3

73--79

Purpose: It is well known that the main portion of artificial sources of ionizing radiation to human results from X-ray imaging techniques. However, reports carried out in various countries have indicated that most of their cumulative doses from artificial sources are due to CT examinations. Hence assessing doses resulted from CT examinations is highly recommended by national and international radiation protection agencies. The aim of this research has been to estimate the effective and organ doses in an average human according to 103 and 60 ICRP tissue weighting factor for six common protocols of Multi-Detector CT (MDCT) machine in a comprehensive training general hospital in Tehran/Iran. Methods: To calculate the patients' effective dose, the CT-Expo2.2 software was used. Organs/tissues and effective doses were determined for about 20 patients (totally 122 patients) for every one of six typical CT protocols of the head, neck, chest, abdomen-pelvis, pelvis and spine exams. In addition, the CT dosimetry index (CTDI) was measured in the standard 16 and 32 cm phantoms by using a calibrated pencil ionization chamber for the six protocols and by taking the average value of CT scan parameters used in the hospital compared with the CTDI values displayed on the console device of the machine. Results: The values of the effective dose based on the ICRP 103 tissue weighting factor were: 0.6, 2.0, 3.2, 4.2, 2.8, and 3.9 mSv and based on the ICRP 60 tissue weighting factor were: 0.9, 1.4, 3, 7.9, 4.8 and 5.1 mSv for the head, neck, chest, abdomen-pelvis, pelvis, spine CT exams respectively. Relative differences between those values were -22, 21, 23, -6, -31 and 16 percent for the head, neck, chest, abdomen-pelvis, pelvis, spine CT exams, respectively. The average value of CTDIv calculated for each protocol was: 27.32 ± 0.9, 18.08 ± 2.0, 7.36 ± 2.6, 8.84 ± 1.7, 9.13 ± 1.5, 10.42 ± 0.8 mGy for the head, neck, chest, abdomen-pelvis and spine CT exams, respectively. Conclusions: The highest organ doses delivered by various CT exams were received by brain (15.5 mSv), thyroid (19.00 mSv), lungs (9.3 mSv) and bladder (9.9 mSv), bladder (10.4 mSv), stomach (10.9 mSv) in the head, neck, chest, and the abdomen-pelvis, pelvis, and spine respectively. Except the neck and spine CT exams showing a higher effective dose compared to that reported in Netherlands, other exams indicated lower values compared to those reported by any other country.