Doses to skin during dynamic perfusion computed tomography of the liver.

Many new computed tomography (CT) techniques have been introduced during the recent years, one of them being CT-assisted dynamic perfusion imaging (perfusion CT, PCT). Many concerns were raised when first cases of deterministic radiation effects were reported. This paper shows how radiochromic films can be utilised as passive dosemeters for use in PCT. Radiochromic dosemeters undergo a colour change directly and do not require chemical processing. Prior to their use, they need to be calibrated. Films are placed on top and on the right side of the patient and exposed during the procedure. Readout is performed using a densitometer. Results show that average local skin doses are 0.51±0.07 and 0.42±0.04 Gy on top and on the lateral side of the patient, respectively. Results of the patient dosimetry (local skin doses) are consistent. This is due to the fact that each patient had the same CT protocol used for imaging (120 kV, 60 mA and C(vol) of 247.75 mGy). Radiochromic films designed for interventional radiology can be effectively used for local skin dose measurements in perfusion CT. Dose values obtained are below the threshold needed for deterministic effects (erythema, hair loss, etc.). These effects might happen if inappropriate CT protocol is used; one that is usually used for routine imaging.

Evaluation of bone remodelling parameters after one year treatment with alendronate in postmenopausal women with osteoporosis.

Antiresorptive agents are widely used to treat osteoporosis. Both reduction in bone turnover and increase in BMD may be necessary to decrease the fracture risk. The aim of the study was to evaluate the effects of aledronate on bone turnover markers and bone mineral density in postmenopausal women with osteoporosis. The study involved a group of 56 postmenopausal women with osteoporosis treated with alendronate (70 mg) weekly at the Institute of Nuclear Medicine Clinical Center University of Sarajevo during a 12-months period. Bone mineral density (BMD) at lumbar spine and proximal femur and bone turnover markers (serum ß-CrossLaps, urinary N-telopeptides of type I collagen (NTx), total serum alkaline phosphatase (AP) and serum osteocalcin) were measured at baseline and after 12 months of the treatment with aledronate. BMD values significantly increased both at lumbar spine by 13.46% and proximal femur by 21.96% during the study period (-3.12±0.24 vs. -2.7±0.19 and -2.55±0.2 vs. -1.99±0.19 respectively; p<0.001). Bone turnover markers significantly decreased during the study period; C-terminal telopeptides of type I collagen fragment (ß-CrossLaps) 49.0% (0.51±0.05 vs.0.26±0.028 ng/mL), NTX 33.4% (48.3±4.9 vs.32.15±3.25 nMBCE/mM Cr), AP 24.3% (81.1±5.2 to 61.43±5.2 IU/L) and serum osteocalcin by 29.7% (34.3±2.65 to 24.1±1.36 ng/mL)(p<0.001). Alendronate treatment increased BMD and reduced the level of bone turnover markers. Therefore, the treatment with aledronate during 12 months period can be recommended in postmenopausal women with osteoporosis.

Patient doses in interventional cardiology in Bosnia and Herzegovina: first results.

Cardiologists at the Cardiac Centre of the Clinical Centre of Sarajevo University performed invasive cardiology procedures in one room equipped with a Siemens Coroskop (Siemens Healthcare, Erlangen, Germany) unit with the possibility of digital cine imaging. The number of procedures performed with this unit is 1126 per year. The number of adults performing only diagnostic procedures is 816, therapeutic procedures 62 and both diagnostic and therapeutic 228. Twenty diagnostic examinations but no therapeutic procedure are performed on children per year. The workload is increasing year by year, with an average increase of 26 % per year. The X-ray system does not have a kerma area product (KAP) meter installed; therefore an external KAP meter was mounted on the X-ray tube. Gafchromic dosimetry films (International Specialty Products, Wayne, USA) were placed under the patient to record the skin dose distribution. The peak skin dose (PSD) was calculated from the maximum optical density of the dosimetry films. Dose measurements were performed on 51 patients undergoing therapeutic procedures (percutaneous transluminal coronary angioplasty and stent placement). Two patients received doses (KAP) larger than 100 Gycm(2). The PSD was higher than 1 Gy in 3 out of 16 evaluations, and one of these patients received a skin dose >2 Gy. No deterministic skin effects were recorded. The dosimetry results are similar to results reported in other countries. Invasive cardiac procedures deliver high doses to the skin that could cause deterministic effects (erythema). Physicians performing these procedures should be aware of these risks. More efforts should be put into the training of cardiologists in radiation protection.

[Thyroid scintigraphy as diagnostic method evaluation of thyroid diseases]. / Scintigrafija stitne zlijezde kao dijagnosticka metoda u evaluaciji oboljenja stitne slijezde.

The thyroid is one of the largest endocrine glands in the body. It may enlarge substanially during pregnancy and when affected by a variety of diseases. The thyroid gland produces hormones, that regulates all metabolic processes and affect the growth and rate of functioning of many other systems in the body. Studies of the endocrine system are among the original procedures in nuclear medicine. Thyroid scintigraphy and radiotracer uptake studies remain an important part of the practice of nuclear medicine. Scintigraphy reveales functional and anatomy changes in status of thyroid gland. A systematic and complete interpretation of the thyroid scintigrams requires assessments of thyroid size and configuration and identification and description of focal abnormalities, including hot and cold nodules and extratyroidal activity in the neck or mediastinum.

Screening of pulmonary embolism by ventilation / perfusion tomography-SPECT and comparation with planar scintigraphy--our experiences.

UNLABELLED: Pulmonary embolism (PE) affects up to 1 per 1000 people every year and is one of the commonest preventable causes of death among hospital inpatients. Laboratory chemical test alone cannot confirm or exclude PE but are used together with the clinical test probability for risk stratification. Ventilation/ perfusion tomographic imaging may be the best practical way to accomplish on this larger scale. The aim of this study was to screen the pulmonary embolism by ventilation/perfusion tomography V/P SPECT. We also compared V/P SPECT with planar scintigraphy. RESULTS: A total of 40 patients with clinically suspected pulmonary embolism were examined. Fifteen patients (37.5%) considered to have perfusion defect with preserved ventilation using ventilation/ perfusion tomography-SPECT. In this group five patients (33%) had multiple perfusion defects (RoPer = 16 poens, RoVent = o poens). Correlation coefficient has been sign among visual analysis and quantitative analysis (C = 0.510). In 25 patients (62.5%) we have found normal ventilation/ perfusion scintigraphy. On the planar scintigraphy PE with high probability was considered in five (26.6%) patients. Intermediate and low probability was considered in seven patients with planar ventilation/ perfusion scintigraphy. Sub-segmental perfusion defect with preserved ventilation we have found in two patients (13%). On the planar scintigraphy the same defect was unclear. CONCLUSIONS: Ventilation/ Perfusion tomography-SPECT is clinically relevant in the diagnosis of pulmonary embolism, and may help reduce the number of non-diagnostic scintigraphy results. On the planar perfusion scintigraphy patients tended to have fewer perfusion defects corresponding pulmonary embolism.

Lymphoscintigraphy and radiation--occupational exposure during sentinel node assay.

Ionizing radiation has many practical applications, but it is also, as it is well known, dangerous to human health. The purpose of this study was to estimate the dose and exposure for medical staff involved in sentinel node assay and to determine how safe this assay really is. The theoretical method was used for calculation. Three groups of medical staff were selected: nuclear medicine specialist, nuclear medicine technologist and a surgeon. The results obtained show that the most exposed staff member is nuclear medicine specialist and that dose received by the surgeon is smaller then the dose limit.