ABSTRACT
Organ doses are important quantities in assessing the radiation risk. In the case of children, estimation of this risk is of particular concern due to their significant radiosensitivity and the greater health detriment. The purpose of this study is to estimate the organ doses to paediatric patients undergoing barium meal and micturating cystourethrography examinations by clinical measurements and Monte Carlo simulation. In clinical measurements, dose-area products (DAPs) were assessed during examination of 50 patients undergoing barium meal and 90 patients undergoing cystourethrography examinations, separated equally within three age categories: namely newborn, 1 year and 5 years old. Monte Carlo simulation of photon transport in male and female mathematical phantoms was applied using the MCNP5 code in order to estimate the equivalent organ doses. Regarding the micturating cystourethrography examinations, the organs receiving considerable amounts of radiation doses were the urinary bladder (1.87, 2.43 and 4.7 mSv, the first, second and third value in the parentheses corresponds to neonatal, 1 year old and 5 year old patients, respectively), the large intestines (1.54, 1.8, 3.1 mSv), the small intestines (1.34, 1.56, 2.78 mSv), the stomach (1.46, 1.02, 2.01 mSv) and the gall bladder (1.46, 1.66, 2.18 mSv), depending upon the age of the child. Organs receiving considerable amounts of radiation during barium meal examinations were the stomach (9.81, 9.92, 11.5 mSv), the gall bladder (3.05, 5.74, 7.15 mSv), the rib bones (9.82, 10.1, 11.1 mSv) and the pancreas (5.8, 5.93, 6.65 mSv), depending upon the age of the child. DAPs to organ/effective doses conversion factors were derived for each age and examination in order to be compared with other studies.
Subject(s)
Barium , Digestive System/diagnostic imaging , Monte Carlo Method , Urinary Bladder Diseases/diagnostic imaging , Urography/methods , Barium/administration & dosage , Body Burden , Child, Preschool , Computer Simulation , Contrast Media/administration & dosage , Digestive System/pathology , Female , Fluoroscopy/methods , Fluoroscopy/standards , Humans , Infant , Infant, Newborn , Male , Organ Specificity , Radiation Dosage , Radiation Protection , Urethra/diagnostic imaging , Urethra/pathology , Urinary Bladder/diagnostic imaging , Urinary Bladder/pathology , Urinary Bladder Diseases/pathology , Urography/standardsABSTRACT
The radiation exposures of children undergoing full spine radiography were investigated in two pediatric hospitals in Greece. Entrance surface kerma (Ka,e) was assessed by thermoluminescence dosimetry and patient's effective dose (E) was estimated by Monte Carlo simulation. All required information regarding patient age and sex, the irradiation geometry, the x-ray spectra, and other exposure parameters (tube voltage and current) were registered as well. Values of Ka,e were measured to range from 0.22 mGy to 2.12 mGy, while E was estimated to range from 0.03 mSv to 0.47 mSv. In general, all values were greater in one of the two hospitals, as higher tube currents and exposure times were used in the examinations because of the difference in radiographers' training and practice. Moreover, dose to red bone marrow was found to be between 0.01 to 0.23 mSv and dose to breast ranged between 0.02 and 1.05 mSv depending on the age, projection, and hospital. These values are comparable with literature sources.
Subject(s)
Computer Simulation , Hospitals, Pediatric , Monte Carlo Method , Radiation Dosage , Radiometry , Scoliosis/diagnostic imaging , X-Rays , Body Burden , Bone Marrow/diagnostic imaging , Breast/radiation effects , Child , Child, Preschool , Greece , Humans , Radiography , Radiometry/adverse effects , Radiometry/methods , Radiometry/statistics & numerical data , Risk AssessmentABSTRACT
This is a double-blind study in which 14 randomly selected patients treated for lung cancer by irradiation, were receiving indomethacin, while 14 patients treated also by irradiation served as controls. The purpose of the study was to investigate a possible protective effect of the drug in irradiation esophagitis. The esophagus was included in the irradiation field in all patients. Histologic findings of esophagitis were not different in the two groups. However, endoscopic esophagitis and symptomatology were milder in the patients who received indomethacin.
Subject(s)
Esophagitis/prevention & control , Indomethacin/therapeutic use , Lung Neoplasms/radiotherapy , Radiation Injuries/prevention & control , Radiotherapy/adverse effects , Clinical Trials as Topic , Double-Blind Method , Esophagitis/etiology , Female , Humans , Male , Middle Aged , Random AllocationABSTRACT
In thalassaemia major, extramedullary haematopoiesis in the form of tumour-like masses, usually occurs in the posterior mediastinum. We present three cases in which such masses were found at the anterior part of the ribs. The radiological signs of this latter location, which is the second most common after the mediastinum, are described.
