A single measurement with (51)Cr-tagged red cells or (125)I-labeled human serum albumin in the prediction of fractional and whole blood volumes: an assessment of the limitations.

This study investigated variations in the prediction of blood volumes from a single measurement of red cell volume (RCV) with (51)Cr or plasma volume (PV) with (125)I human serum albumin (HSA). In 111 subjects, fractional and whole blood volumes were estimated from separate direct measurements of RCV and PV. The f ratio (body to venous hematocrit) was also determined.

The dependence of patient dose on factors relating to the technique and complexity of Interventional Cardiology procedures.

Dose-area product (DAP) measurements were conducted for 168 coronary angiography (CA) and 89 single vessel percutaneous transluminal coronary angioplasty (PTCA) to examine the factors influencing patient dose beyond the X-ray exposure parameters. It was found that for CA, the DAP increases with the number of catheters used and with the number of vessels with stenosis. DAP values for patients with a prior bypass surgery, were higher compared to those without such a medical record to surgery.

The variation of intrinsic spatial resolution across the UFOV of scintillation cameras.

The aim of the present study was to investigate in detail the variation of the intrinsic spatial resolution across the useful field of view (UFOV) of gamma-cameras and to explore whether this variation could lead to observable effects in clinical images. Two gamma-cameras were used, without their collimators, to acquire 560 (99m)Tc point source images at different points across their UFOVs, in order to measure the intrinsic spatial resolution at each point. Possible clinical effects of the resolution variation were examined on images of a thyroid phantom using a LEHR collimator, acquired at different locations on the UFOV and at various distances from the collimator.

Translation and validation of the Depression Outcomes Module (DOM) in Greece.

In Greece, as in other countries, major depressive disorder is underdiagnosed. Its severity, implications and outcomes are often not adequately evaluated. The Depression Outcomes Module (DOM) was developed in order to meet the need for a global assessment of this disorder.

Quality control and diagnostic reference levels in intraoral dental radiographic facilities.

Objectives: A quality control program in intraoral radiographic equipment was conducted aiming to verify compliance with the latest legal requirements and to measure radiation dose in order to contribute to the establishment of appropriate diagnostic reference levels.

Methods: This study was performed in 191 intraoral radiographic facilities in Northern Greece. The quality control program included visual inspection of the unit, registration of its characteristics, measurement and calculation of several radiological parameters, including entrance surface dose, and overall compliance with legislation requirements.

Skin doses to patients undergoing coronary angiography in a Greek hospital.

In this study, the skin dose (SD) to patients undergoing coronary angiography (CA) were measured with thermoluminescence dosemeters (TLD) attached to various anatomical locations on the patient's skin during 93 CA procedures in a Greek hospital. The dose-area product (DAP) for every radiological projection was also measured for each procedure. The SD values were measured to be in the range 2.

Radiation doses to patients undergoing barium meal and barium enema examinations.

The radiation doses received by patients during 41 barium meal (BM) and 42 barium enema (BE) examinations in two Greek hospitals are presented. Radiation dose was measured in terms of the dose area product (DAP). The effective dose and doses to certain organs were estimated using the ODS-60 software.

Radiation exposure to cardiologists performing interventional cardiology procedures.

Medical doctors, who practice interventional cardiology, receive a noticeable radiation dose. In this study, we measured the radiation dose to 9 cardiologists during 144 procedures (72 coronary angiographies and 70 percutaneus translumined coronary angioplasties) in two Greek hospitals. Absorbed doses were measured with TLD placed underneath and over the lead apron at the thyroid protective collar.

A contribution to the establishment of diagnostic reference levels in CT.

CT has become the major source of population exposure to diagnostic X-rays. CT dose index (CTDI) and dose-length product (DLP) have been proposed as the appropriate dose quantities for the establishment of diagnostic reference levels for optimizing patient exposure. Dose measurements on 27 CT scanners in Northern Greece involving six routine CT examinations have been performed in order to compare their performance with the currently proposed European reference dose values and to produce a preliminary set of data for the establishment of local diagnostic reference levels.

Radiation doses to patients undergoing coronary angiography and percutaneous transluminal coronary angioplasty.

A detailed study of radiation doses received by 168 patients who underwent coronary angiography (CAG) and 102 patients who underwent percutaneous transluminal coronary angioplasty (PTCA) in two Greek hospitals is presented. Radiation dose was measured in terms of dose-area product (DAP). The contribution of fluoroscopy and cineradiography to the total DAP was examined separately for each radiological projection used in both procedures.

Prevalence of migraine in schoolchildren and some clinical comparisons between migraine with and without aura.

Objectives: To determine the prevalence of migraine and its association with age, gender, and social class and to find out whether or not the headache and nonheadache characteristics differ between children with migraine, with and without aura, using the diagnostic criteria of the International Headache Society for childhood migraine.

Design: Population-based study in two stages comprising an initial screening questionnaire followed by telephone interviews of children with symptoms.

Setting: Eighteen kindergarten and 39 primary and secondary schools in Thessaloniki and its semiurban areas.

Dosimetric considerations in mammography.

The aim of this study was to measure the absorbed dose to seven organs other than the breast in mammography in order to calculate their contribution to the effective dose. The absorbed dose to these organs was measured using a lucite upper body anthropomorphic phantom containing thermoluminescent dosimeters (TLD) at appropriate locations, exposed as in a mammographic examination. In addition, the dependence of the absorbed dose on kVp, mAs and breast thickness was examined.