Radiologic Technology

The purpose of this study was to evaluate the effect of a switch to a filmless image management system on the time required for technologists to produce radiographic images in the emergency department (ED) after controlling for exam difficulty and a variable workload. Time and motion data were collected on patients who had radiographic images taken while being treated in the emergency department over the 3½-year period from April 1997 to November 2000. Event times and demographic data were obtained from the radiology information system, from the hospital information system, from emergency department records, or by observation by research coordinators. Multiple least squares regression analysis identified several independent predictors of the time required for technologists to produce radiographic images. These variables included the level of technologist experience, the number of trauma-alert patient arrivals, and whether a filmless image management system was used (all P < .05). Our regression model explained 22% of the variability in technologist time (R 2 Adjusted, 0.22; F = 24.01; P < .0001). The regression model predicted a time saving of 2 to 3 minutes per patient in the elapsed time from notification of a needed examination until image availability because of the implementation of PACS, a delay of 4 to 6 minutes per patient who were imaged by technologists who spent less than 10% of their work assignments within the ED, and a delay of 18 to 27 minutes in radiology workflow because of the arrival of a trauma alert patient. A filmless system decreased the amount of time required to produce radiographs. The arrival of a trauma alert patient delayed radiology workflow in the ED. Inexperienced technologists require 4 to 6 minutes of additional time per patient to complete the same amount of work accomplished by an experienced technologist.

With the profession of radiology experiencing workforce shortages among radiologists and radiological technologists many radiological groups were beginning to hire ancillary personnel to fill efficiency gaps in practices. Many academic institutions were in the process of considering ...

Data are limited on the role of chronic exposure to lowdose ionizing radiation in the etiology of cancer. In a nationwide cohort of 146,022 U.S. radiologic technologists (73% female), we evaluated mortality risks in relation to work characteristics. Standardized mortality ratios (SMRs) were computed to compare mortality in the total cohort vs. the general population of the United States. Mortality risks were low for all causes (SMR ‫؍‬ 0.76) and for all cancers (SMR ‫؍‬ 0.82) among the radiologic technologists. We also calculated relative risks (RR) for the 90,305 technologists who responded to a baseline mailed questionnaire, using Poisson regression models, adjusted for known risk factors. Risks were higher for all cancers (RR ‫؍‬ 1.28, 95% confidence interval [CI] ‫؍‬ 0.93-1.69) and breast cancer (RR ‫؍‬ 2.92, 95% CI ‫؍‬ 1.22-7.00) among radiologic technologists first employed prior to 1940 compared to those first employed in 1960 or later, and risks declined with more recent calendar year of first employment (p-trend ‫؍‬ 0.04 and 0.002, respectively), irrespective of employment duration. Risk for the combined category of acute lymphocytic, acute myeloid and chronic myeloid leukemias was increased among those first employed prior to 1950 (RR ‫؍‬ 1.64, 95% CI ‫؍‬ 0.42-6.31) compared to those first employed in 1950 or later. Risks rose for breast cancer (p-trend ‫؍‬ 0.018) and for acute lymphocytic, acute myeloid and chronic myeloid leukemias (p-trend ‫؍‬ 0.05) with increasing duration of employment as a radiologic technologist prior to 1950. The elevated mortality risks for breast cancer and for the combined group of acute lymphocytic, acute myeloid and chronic myeloid leukemias are consistent with a radiation etiology given greater occupational exposures to ionizing radiation prior to 1950 than in more recent times.

The diagnosis of subtle slipped capital femoral epiphysis (SCFE), for example in the contralateral asymptomatic hip, may require use of an exactly defined and reproducible lateral view where the slipping angle can be measured. To test a simplified geometrical method and compare it to the conventional method (AP and frogleg views). The two methods were compared in 95 normal children 9-14 years old and 100 children 9-20 years old with SCFE. The slipping angle (SA) measurements had very high reproducibility, and the new method was diagnostically superior to the conventional method ( P&lt;0.05). An exactly defined and reproducible lateral view is recommended for the X-ray diagnosis of SCFE. Nontraumatic SCFE appears to be bilateral in all cases.

GT Herman optimized (on a sufficiently large data set so as to lead to statistically significant results) without outrageous demands on computational resources. In the rest of this section we discuss how the image reconstruction problem arises in a number of bio- medical areas. ...

OBJECTIVE To describe perceptions of patient safety culture (PSC) among US vascular interventional technologists (VIR). METHODS A letter to complete The Hospital Survey on Patient Safety Culture online was distributed in the US to all full-time American Registry of Radiologic Technologists (ARRT)-registered technologists with a primary discipline of cardiac-interventional or vascular interventional (n=3,184). Mean scores on each PSC dimension and overall outcome measures were calculated. RESULTS The response rate was 13.7% (n=437) for the entire universe of ARRT-registered VIR technologists working full-time. Overall, respondents ranked the following dimensions as supporting patient safety within their respective institution: supervisor/manager promotion of patient safety, staffing, hospital handoffs/transitions, and teamwork within units. Neutral perceptions focused on teamwork across hospital units, hospital management&#39;s support for patient safety, and nonpunitive response to ...

Purpose: To scrutinize the positioning accuracy and reproducibility of a commercial hexapod robot treatment table (HRTT) in combination with a commercial cone-beam computed tomography system for image-guided radiotherapy (IGRT). Methods and Materials: The mechanical stability of the X-ray volume imaging (XVI) system was tested in terms of reproducibility and with a focus on the moveable parts, i.e., the influence of kV panel and the source arm on the reproducibility and accuracy of both bone and gray value registration using a head-and-neck phantom. In consecutive measurements the accuracy of the HRTT for translational, rotational, and a combination of translational and rotational corrections was investigated. The operational range of the HRTT was also determined and analyzed. Results: The system performance of the XVI system alone was very stable with mean translational and rotational errors of below 0.2 mm and below 0.2°, respectively. The mean positioning accuracy of the HRTT in combination with the XVI system summarized over all measurements was below 0.3 mm and below 0.3°for translational and rotational corrections, respectively. The gray value match was more accurate than the bone match. Conclusion: The XVI image acquisition and registration procedure were highly reproducible. Both translational and rotational positioning errors can be corrected very precisely with the HRTT. The HRTT is therefore well suited to complement cone-beam computed tomography to take full advantage of position correction in six degrees of freedom for IGRT. The combination of XVI and the HRTT has the potential to improve the accuracy of high-precision treatments. © 2007 Elsevier Inc.

A significant metric in federal mammography quality standards is the phantom image quality assessment. The present work seeks to demonstrate that automated image analyses for American College of Radiology ͑ACR͒ mammographic accreditation phantom ͑MAP͒ images may be performed by a computer with objectivity, once a human acceptance level has been established. Twelve MAP images were generated with different x-ray techniques and digitized. Nineteen medical physicists in diagnostic roles ͑five of which were specially trained in mammography͒ viewed the original film images under similar conditions and provided individual scores for each test object ͑fibrils, microcalcifications, and nodules͒. Fourier domain template matching, used for low-level processing, combined with derivative filters, for intermediate-level processing, provided translation and rotation-independent localization of the test objects in the MAP images. The visibility classification decision was modeled by a Bayesian classifer using threshold contrast. The 50% visibility contrast thresholds established by the trained observers' responses were: fibrils 1.010, microcalcifications 1.156, and nodules 1.016. Using these values as an estimate of human observer performance and given the automated localization of test objects, six images were graded with the computer algorithm. In all but one instance, the algorithm scored the images the same as the diagnostic physicists. In the case where it did not, the margin of disagreement was 10% due to the fact that the human scoring did not allow for half-visible fibrils ͑agreement occurred for the other test objects͒. The implication from this is that an operator-independent, machine-based scoring of MAP images is feasible and could be used as a tool to help eliminate the effect of observer variability within the current system, given proper, consistent digitization is performed. © 1997 American Association of Physicists in Medicine. ͓S0094-2405͑97͒00205-8͔

The picture archiving and communication system (PACS) is an image information system that has become widely installed. For its successful implementation, training has been found indispensable. A review of PACS training thus far shows major emphasis was placed on the use of display workstations. As an integrated system, the PACS is much broader than the display workstations, having many components that need connectivity and customization. With the many potentials of further development, a more comprehensive education program on PACS is called for and a PACS simulator as a standalone training and research tool is deemed necessary. q

The use of computers is increasing in every field of medicine, especially radiology. Filmless radiology departments, speech recognition software, electronic request forms and teleradiology are some of the recent developments that have substantially increased the amount of time a radiologist spends in front of a computer monitor. Computers are also needed for searching literature on the internet, communicating via e-mails, and preparing for lectures and presentations. It is well known that regular computer users can suffer musculoskeletal injuries due to repetitive stress. The role of ergonomics in radiology is to ensure that working conditions are optimized in order to avoid injury and fatigue. Adequate workplace ergonomics can go a long way in increasing productivity, efficiency, and job satisfaction. We review the current literature pertaining to the role of ergonomics in modern-day radiology especially with the development of picture archiving and communication systems (PACS) workstations.

The purpose of the study was to determine prevalent conflict management styles chosen by students in nursing and to contrast these styles with those chosen by students in allied health professions. The associations among the level of professional health care education and the style chosen were also determined. A convenience sample of 126 students in a comprehensive university completed the Thomas-Kilmann Conflict Mode Instrument (TKI), which requires respondents to choose behaviors most characteristic of their response to conflict and classifies these behaviors as one of five styles. There was no significant difference between the prevalent conflict management styles chosen by graduate and undergraduate nursing students and those in allied health. Some of the students were already licensed in their discipline; others had not yet taken a licensing exam. Licensure and educational level were not associated with choice of styles. Women and men had similar preferences. The prevalent style for nursing students was compromise, followed by avoidance. In contrast, avoidance, followed by compromise and accommodation, was the prevalent style for allied health students. When compared to the TKI norms, slightly more than one half of all participants chose two or more conflict management styles, commonly avoidance and accommodation at the 75th percentile or above. Only 9.8% of the participants chose collaboration at that level. Implications for nurse educators, researchers, and administrators are discussed. (

Radiologic Education has substantially changed throughout the years and has certain advancements that have left the country catching on. It has transitioned from analog to digital imaging, which considerably left developing countries behind. Consequently, general radiography practices are assumed to differ from the previous years. Employing a sequential explanatory research design, the study looked into the radiologic interns' competencies in specific parameters such as preparation, patient care and management; positioning; and image acquisition and processing. Using a researcher-made questionnaire, 50 radiologic interns from four academic year batches were invited to participate in the study. Interpreted responses are cross-referenced through the interview data that were gathered from 12 participants, equally representing each batch. The study also probed the interns' general learning preference using the VARK questionnaire. Both of the questionnaires underwent Cronbach Alpha Test of Reliability. The data was probed and analyzed using Regression Analysis; to which the research findings gave an inference that the learning preferences positively affect the clinical competencies of the radiologic interns, providing the institution a broader perspective on improving the interns' educative capacity. It also strengthens the Radiologic Technology program, giving importance to the three generated themes: Rehearsals of procedures, Application more than Theories, and Demonstration of Skills.

The purposes of this study were to determine, by state, the requirements for dual-energy X-ray absorptiometry (DXA) operators' training, knowledge of these state requirements, and factors that predicted state and International Society of Clinical Densitometry (ISCD) certification of DXA technologists. Seventeen states required registered technologist (RT) certification or authorized/licensed limited certification for DXA operators, 16 had no certification requirements, 12 required RT certification, and 5 had state-specific requirements. There were 9745 surveys mailed to DXA users including 50% Hologic Inc., 50% GE Lunar, and 100% Norland; 3148 surveys are included in this analysis. Among responders who indicated that their state did not have any certification requirements (n = 1673), 1095 (65.5%) were incorrect; there were requirements. Possession of state and ISCD certification was significantly correlated with the number of patients scanned per week (p ≤ 0.05), the number of technologists employed within a center (p < 0.01), and the subspecialty of the practitioner (p ≤ 0.02). Our study uncovered a lack of uniformity among states with respect to central DXA operator training requirements. Additionally, in those states with requirements, DXA operators were often unaware of these requirements. Uniform national training requirements for central DXA operators to ensure adequate DXA scan quality are urgently needed.

X-ray is being used widely in medical and in other fields of science, engineering, and technology since its invention in the year 1895. Globally, the growing number of general population and the high prevalence of various critical diseases are augmenting the need for X-ray imaging equipment for an accurate diagnosis. Although X-ray tube technology (Coolidge tube) is about 106 years old, it has been still used widely today for medical diagnostic imaging. Various types of X-ray tubes are classified. The indicative list for the standards pertaining to performance and safety of medical electrical equipment and diagnostic X-ray tube assembly includes the following: IEC 60601-1-2/IS 13450-1-2, IEC 60601-
1-3/IS 13450-1-3, IEC 60601-1-6, IEC 60601-1-8, IEC 60601-1-9, IEC 60601-2-28, IEC 60601-2-54, IEC 60522, IEC 60806, IEC 60336, IEC 61267, IEC 61674, IEC 61676, IEC 60613, IEC 60526, IEC 62304, IEC 62366, ISO 13485, ISO 14000, ISO 14971, and ISO 10993-1. The manufacturing processes of the X-ray tube assembly are listed as follows: (step 1) X-ray tube insert parts processing and cleaning; (step 2) X-ray tube insert parts (anode and cathode) assembly processing; (step 3) glass or metal-ceramic envelope processing; (step 4) degassing of X-ray tube insert; (step 5) seasoning of X-ray tube insert; (step 6) X-ray tube assembly processing; (step 7) final testing of X-ray tube assembly; and (step 8) quality control of X-ray tube assembly. As per the recommendations of Atomic Energy Regulatory Board (AERB), Government of India, the accuracy of the applied X-ray tube potential of the general radiography and fluoroscopy, computed tomography, mammography, and dental X-ray machine should be within +/-5, +/-2, +/-1, and +/-5, respectively, of the corresponding measured values.
Linearity of the X-ray tube current (mA or mAs) loading stations (coefficient of linearity (CoL)) of the general radiography and fluoroscopy, computed tomography, mammography, and dental X-ray machine should be within <0.1, +/-0.1, +/-0.1, and <0.1, respectively. The most common causes for the X-ray tube failures include the following: (i) cathode filament burnout, (ii) target micro-cracking, (iii) tube arcing, (iv) slow leaks in the tube, and (v) bearings of rotating anode. Globally, more than 20,000 patents have been filed so far on the innovations of X-ray tube technology

A ten-year tracer study of Radiologic Technology graduates of Lyceum of the Philippines University SY 1997-2007 using a survey-structured questionnaire was conducted to examine retrospective contribution of their education to their current work. The objectives of the study included the determination of graduates' job-placement profile; how relevant are school-related factors like curriculum, instruction, faculty; student services; organization and administration, physical plant, facilities and laboratories to the job placement; the determination of what skills developed while at school are considered useful in meeting the demands of their present work and the formulation of a program that will enhance the relevance of the college curriculum and services. A total of 97/122 (80%) graduates responded where 78% (76/97) are certified licensed radiographers. All respondents were employed on a full-time basis aligned to the program. The following were found to be very relevant in meeting the demands of their jobs: curriculum, instruction, competencies of the faculty, student services, organization and administrative services.Furthermore, the intellectual, communication and interpersonal skills, competencies, and workrelated values they learned and developed while at school as well as the performance in written and oral assessment of the employers were considered the most important contributing factors in seeking employment after graduation.

For many years, P6 vials have been used for the distribution of a wide range of diagnostic and therapeutic radioactive solutions. The activity measurements were performed in this geometry and, in time, the UK calibration system for nuclear medicine was based on this container as a standard. However, one major supplier of radiopharmaceuticals has replaced the P6 vial with the 10R Type 1+ Schott vial. As the dimensions of the new vial are different from those of the P6 vial and the responses of radionuclide calibrators are known to be container dependent, the need for re-calibration became apparent. Preliminary measurements made on some typical radionuclide calibrators for 125 I solution indicated a difference in response of about 10% between the two vials.

Dynamic, flat-panel, solid-state, x-ray image detectors for use in digital fluoroscopy and fluorography emerged at the turn of the millennium. This new generation of dynamic detectors utilize a thin layer of x-ray absorptive material superimposed upon an electronic active matrix array fabricated in a film of hydrogenated amorphous silicon (a-Si:H). Dynamic solid-state detectors come in two basic designs, the indirect-conversion (x-ray scintillator based) and the direct-conversion (x-ray photoconductor based). This review explains the underlying principles and enabling technologies associated with these detector designs, and evaluates their physical imaging characteristics, comparing their performance against the long established x-ray image intensifier television (TV) system. Solid-state detectors afford a number of physical imaging benefits compared with the latter. These include zero geometrical distortion and vignetting, immunity from blooming at exposure highlights and negligible contrast loss (due to internal scatter). They also exhibit a wider dynamic range and maintain higher spatial resolution when imaging over larger fields of view. The detective quantum efficiency of indirect-conversion, dynamic, solid-state detectors is superior to that of both x-ray image intensifier TV systems and direct-conversion detectors. Dynamic solid-state detectors are playing a burgeoning role in fluoroscopy-guided diagnosis and intervention, leading to the displacement of x-ray image intensifier TV-based systems. Future trends in dynamic, solid-state, digital fluoroscopy detectors are also briefly considered. These include the growth in associated three-dimensional (3D) visualization techniques and potential improvements in dynamic detector design.

There appears to be a decline in the clinical competence of students during their internship. This study aims to determine the clinical competencies of Radiologic Technology Interns of Batch 2018-2019 on Radiological Science Modalities and propose an enhancement program based on the findings of the study. A descriptive method using the Clinical Evaluation Tool was employed to elicit data on 34 respondents who were chosen through purposive sampling technique. Clinical competencies data were collected from the Clinical Coordinator of Davao Doctors College Radiologic Technology Program.Results showed that majority of the respondents were female (71%) while all of the respondents rotated in five Radiological Science Modalities.The overall clinical competency on Computed Tomography, Magnetic Resonance Imaging, Nuclear Medicine, Radiation Therapy and Ultrasound was low. Test of difference revealed that there is no significant difference in the clinical competencies of respondents when grouped according to sex (p>0.05) but there is significant difference in the clinical competencies when grouped according to Radiological Science Modalities (p<0.05). Results also showed that there is no significant difference in the overall clinical competency on Computed Tomography, Nuclear Medicine, Radiation Therapy, and Ultrasound when respondents are grouped according to sex (p>0.05) butthere is significant difference in the overall clinical competency on Magnetic Resonance Imaging when respondents are grouped according to sex (p<0.05). Based on the findings of the study, a proposed enhancement program on all Radiological Science Modalities was developed.

Examination of human remains in archaeological contexts presents significant challenges. They are frequently located within sites of religious and cultural significance and this, coupled with their often-fragile nature, necessitates their examination in situ. These sites may also be in remote locations which present major logistical challenges. The strategies developed to overcome these challenges have implications for the management of post-mortem imaging examinations following mass casualty events in remote areas. This paper presents the paleoimaging and bioarchaeological analysis of 36 mummies within the burial chambers of the mother church of Saint Nicholas of Bari in Gangi, Sicily. Research questions included assessments of the state of external and internal preservation, age at death, mummification method, presence of pathologies and trauma, and the nature of the wax masks. Circumstances dictated that examination of the mummies should take place within the burial chamber and within a short time-frame. Methodology employed macroscopic examination and a multimodal imaging approach including photography, endoscopy, XRF, and two portable digital radiography stations. The methodological design adopted improved efficiency and efficacy. The use of two digital radiography stations for separate AP and lateral survey radiographs greatly improved throughput and minimized lifting and handling of the remains. All examinations (602 radiographs) were completed within under 15 hours. The methodology is an efficient model for studies in similar bioarchaeological and forensic situations and for the examination of the victims of mass casualty events in remote locations.

This study aimed to determine the employability of Radiologic Technology graduates from 2013 to 2015. Descriptive type of research was utilized in the study. Results showed that there are 93.8 percent of the BSRT graduates are gainfully employed locally with regular or permanent status. Majority of them landed a job one (1) to 2 years. Career challenge and relevance of course completed to job assignment are the reasons of the graduates for accepting and staying on the job. Communication and critical thinking skills are considered very useful in most BSRT graduates in meeting the demands of their present job. The value of hard work contributed very much to the job placement of most Radiologic Technology graduate-respondents followed by leadership, perseverance, honesty and love for truth and courage (3.64). Courses in Natural science are considered the number one (1) useful aspect for their employment in terms of General Education while Human Anatomy & Physiology and Radiographic Anatomy & Physiology are considered two of the most relevant professional courses to their present employment.

Traditionally, a practicum facilitated the integration of on-campus learning and practical workplace training. Over the past 3 decades, an educative practicum has evolved that promotes clinical reasoning, including analytical and evaluative abilities, through reflective practice. Anecdotal evidence indicates that the delivery of clinical education within medical radiation science entry-level programs continues to vacillate between traditional practicums and the new reflective practicums. To review the literature about clinical education within the medical radiation sciences and identify key principles for practitioners seeking to reflect upon and improve their approach to teaching and supporting students in the clinical environment. A search of 3 major journal databases, Internet searches, and hand searches of reference lists were conducted to identify literature about clinical education in the medical radiation sciences from January 1, 2000, to December 31, 2012. Twenty-two studies...

A ten-year tracer study of Radiologic
Technology graduates of Lyceum of the Philippines
University SY 1997-2007 using a survey-structured
questionnaire was conducted to examine retrospective
contribution  of  their  education  to  their  current
work.  The  objectives  of  the  study  included  the
determination  of  graduates’  job-placement  profile;
how relevant are school-related factors like curriculum,
instruction,  faculty;  student  services;  organization
and  administration,  physical  plant,  facilities  and
laboratories to the job placement; the determination of
what skills developed while at school are considered
useful in meeting the demands of their present work
and the formulation of a program that will enhance
the relevance of the college curriculum and services.
A total of 97/122 (80%) graduates responded where
78%  (76/97)  are  certified  licensed  radiographers.
All respondents were employed on a full-time basis aligned to the program. The following were found to
be very relevant in meeting the demands of their jobs:
curriculum, instruction, competencies of the faculty,
student  services,  organization  and  administrative
services.Furthermore, the intellectual, communication
and  interpersonal  skills,  competencies,  and  work-
related values they learned and developed while at
school as well as the performance in written and oral
assessment of the employers were considered the most
important contributing factors in seeking employment
after graduation.

Sebagian besar infeksi virus penyebab pilek seperti common cold dapat menyebabkan suatu sumbatan pada rongga hidung yang akan hilang dalam beberapa hari. Namun jika terjadi peradangan pada bagian sinusnya maka akan muncul gejala lainnya. Sinus atau sering pula disebut dengan sinus paranasalis adalah rongga udara yang terdapat pada bagian padat dari tulang tenggkorak disekitar wajah yang berfungsi untuk memperingan tulang tenggkorak. Rongga ini berjumlah empat pasang di kiri dan kanan.

Abdominal aortic aneurysm (AAA) is a significant disease affecting the circulatory system. Risk factors include smoking, hypertension, sex, and a possible hereditary predisposition. AAAs remain asymptomatic for years, and various imaging methods are used in their detection, diagnosis, and treatment. This article reviews the anatomy and physiology of the aorta as well as the signs and symptoms, pathophysiology, epidemiology, and risk factors for the development of AAA. The use of ultrasonography and other imaging modalities for pre- and post-treatment is discussed, as is endovascular aortic repair.

A knowledge of photon energy spectra emitted from X-ray tubes in radiology is crucial for many research domains in the medical field. Since spectrometry is difficult because of high photon fluence rates, a convenient solution is to use computational models. This paper describes the use of six computer codes based on semiempirical or empirical models. The use of the codes was assessed, notably by comparing theoretical half value layers and air kerma with measurements on five different X-ray tubes used in a research hospital. It was found that three out of the six computer codes give relative spectra very close to those produced by X-ray units equipped with constant potential generators: the mean difference between measured and modelled half value layer was less than 3% with a standard deviation of 3.6% whatever the tube and the applied voltage. Absolute output is less accurate: for four computer codes, the mean difference between the measured and modelled air kerma was between 18% and 36%, with a standard deviation of 9% whatever the tube (except for the single phase generator) and the applied voltage. One of the codes gives a good output and beam quality for X-ray units equipped with 100% ripple voltage generators. The use of computational codes as described in this paper provides a means of modelling relative diagnostic X-ray spectra, the usefulness of the tube output data depending on the accuracy required by the end user.

Background
Computed tomography (CT) examinations account for a significant portion of individuals’ increasing exposure to medical radiation. Automatic exposure control (AEC) was introduced in CT scanners to decrease patient doses while maintaining appropriate image quality.

Objective
To identify areas for AEC optimization and suggest practical optimization methods.

Methods
A literature review was conducted to assess current knowledge regarding tube current modulation and AEC in CT from peer-reviewed journals and publications from national and international organizations involved in medical imaging and radiation protection.

Results
Four important aspects of AEC use were identified: interaction of user-selectable parameters with AEC, patient positioning and AEC, specific challenges with patient size groups and how to select appropriate input value.

Conclusion
AEC is a useful tool for dose optimization but dose savings are not guaranteed unless the equipment is used properly. Further research is required into optimal use of AEC, particularly for pediatric examinations.

This study aimed to determine the employability of Radiologic Technology graduates from 2013 to 2015. Descriptive type of research was utilized in the study. Results showed that there are 93.8 percent of the BSRT graduates are gainfully employed locally with regular or permanent status. Majority of them landed a job one (1) to 2 years. Career challenge and relevance of course completed to job assignment are the reasons of the graduates for accepting and staying on the job. Communication and critical thinking skills are considered very useful in most BSRT graduates in meeting the demands of their present job. The value of hard work contributed very much to the job placement of most Radiologic Technology graduate-respondents followed by leadership, perseverance, honesty and love for truth and courage (3.64). Courses in Natural science are considered the number one (1) useful aspect for their employment in terms of General Education while Human Anatomy & Physiology and Radiographic Anatomy & Physiology are considered two of the most relevant professional courses to their present employment.

Purpose: To present treatment planning case studies for several treatment sites for which volumetric modulated arc therapy (VMAT) could have a positive impact; and to share an initial clinical experience with VMAT for stereotactic body radiotherapy (SBRT). Methods and Materials: Four case studies are presented to show the potential benefit of VMAT compared with conformal and intensity-modulated radiotherapy (IMRT) techniques in pediatric cancer, bone marrow-sparing whole-abdominopelvic irradiation (WAPI), and SBRT of the lung and spine. Details of clinical implementation of VMAT for SBRT are presented. The VMAT plans are compared with conventional techniques in terms of dosimetric quality and delivery efficiency. Results: Volumetric modulated arc therapy reduced the treatment time of spine SBRT by 37% and improved isodose conformality. Conformal and VMAT techniques for lung SBRT had similar dosimetric quality, but VMAT had improved target coverage and took 59% less time to deliver, although monitor units were increased by 5%. In a complex pediatric pelvic example, VMAT reduced treatment time by 78% and monitor units by 25% compared with IMRT. A double-isocenter VMAT technique for WAPI can spare bone marrow while maintaining good delivery efficiency. Conclusions: Volumetric modulated arc therapy is a new technology that may benefit different patient populations, including pediatric cancer patients and those undergoing concurrent chemotherapy and WAPI. Volumetric modulated arc therapy has been used and shown to be beneficial for significantly improving delivery efficiency of lung and spine SBRT. Ó

The purpose of this study was to present the variation of clinical target volume (CTV) with different computed tomography (CT) slice thicknesses and the impact of CT slice thickness on 3-dimensional (3D) conformal radiotherapy treatment planning. Fifty patients with brain tumors were selected and CT scans with 2.5-, 5-, and 10-mm slice thicknesses were performed with non-ionic contrast enhancement. The patients were selected with tumor volume ranging from 2.54 cc to 222 cc. Three-dimensional treatment planning was performed for all three CT datasets. The target coverage and the isocenter shift between the treatment plans for different slice thickness were correlated with the tumor volume. An important observation from our study revealed that for volume < 25 cc, most of the cases were underdosed by 18% with 5-mm slice thickness and 27% with 10-mm slickness. For volume > 25 cc, the target underdosage was less than 6.7% for 5-mm slice thickness and 8% for 10-mm slice thickness. For 3D conformal radiotherapy treatment planning (3DCRT), a CT slice thickness of 2.5 mm is optimum for tumor volume < 25 cc, and 5 mm is optimum for tumor volume > 25 cc.

Radionuclides are used in nuclear medicine in a variety of diagnostic and therapeutic procedures. A knowledge of the radiation dose received by dierent organs in the body is essential to an evaluation of the risks and bene®ts of any procedure. In this paper, current methods for internal dosimetry are reviewed, as they are applied in nuclear medicine. Particularly, the Medical Internal Radiation Dose (MIRD) system for dosimetry is explained, and many of its published resources discussed. Available models representing individuals of dierent age and gender, including those representing the pregnant woman are described; current trends in establishing models for individual patients are also evaluated. The proper design of kinetic studies for establishing radiation doses for radiopharmaceuticals is discussed. An overview of how to use information obtained in a dosimetry study, including that of the eective dose equivalent (ICRP 30) and eective dose (ICRP 60), is given. Current trends and issues in internal dosimetry, including the calculation of patient-speci®c doses and in the use of small scale and microdosimetry techniques, are also reviewed. # : S 0 9 6 9 -8 0 4 3 ( 9 8 ) 0 0 0 2 3 -2 Applied Radiation and Isotopes PERGAMON * To whom all correspondence should be addressed. per unit time, integrating this over time gives the total number of disintegrations.

Boron neutron capture therapy (BNCT) is a form of radiation therapy mediated by the short-range (less than 10 fim) energetic alpha ( 4 He) and lithium-7 ( 7 Li) ionizing particles that result from the prompt disintegration by slow neutrons of the stable-(nonradioactive) nucleus boron-10 ( 10 B). Recent advances in radiobiological and toxicological evaluation of tumour-affirutive boron-containing drugs and in optimization of the energies of neutrons in the incident beam have spurred interest in BNCT. This article presents a history of BNCT that emphasizes studies in the USA. A new dosimetric analysis of the 1959-1961 clinical trials of BNCT at Brookhaven National Laboratory is also presented. This analysis yields an acute radiation dose tolerance limit estimate of -10 Gy-Eq to the capillary endothelium of human basal ganglia from BNCT. (Gy-Eq: Gray-equivalent, or relative biological effectiveness of a radiation component multiplied by the physical dose of the component (Gy), summed over the component kinds of radiation.)

Purpose: To develop a method for treatment planning and optimization of magnetic resonance imaging (MRI)assisted gynecologic brachytherapy that includes biologically weighted total dose constraints. Methods and Materials: The applied algorithm is based on the linear-quadratic model and includes dose, dose rate, and fractionation of the whole radiotherapy setting, consisting of external beam therapy plus high-dose-rate (HDR), low-dose-rate (LDR) or pulsed-dose rate (PDR) brachytherapy. Biologically effective doses (BED) are converted to more familiar isoeffective (equivalent) doses in 2-Gy fractions. For individual treatment planning of each brachytherapy fraction, the algorithm calculates the physical dose per brachytherapy fraction that corresponds to a predefined isoeffective total dose constraint. Achieved target dose and sparing of organs at risk of already delivered brachytherapy fractions are incorporated. Results: Since implementation for use in clinical routine in 2001, MRI assisted treatment plans of 216 gynecologic patients (161 HDR, 55 PDR brachytherapy) were prospectively optimized taking into account isoeffective dose-volume histogram-based total dose constraints for high-risk clinical target volume (HR CTV) and organs at risk (bladder, rectum, sigmoid). The algorithm is implemented in a spreadsheet and the procedure is fast and efficient. An uncertainty analysis of the isoeffective total doses based on variations of tissue parameters shows that confidence intervals are larger for PDR compared with HDR brachytherapy. For common treatment schedules, overall uncertainties of high-risk clinical target volume and organs at risk are within 8 Gy, except for the bladder when using the PDR technique. Conclusion: The presented method to respect total dose constraints is reliable and efficient and an essential tool when aiming to increase local control and minimize side effects. Ó 2007 Elsevier Inc.

The problem of simultaneously exposing large numbers of culture flasks at nominally equivalent incident power densities and with good thermal control is considered, and the radial transmission line (RTL) is proposed as a solution. The electromagnetic design of this structure is discussed, and an extensively bench-tested realization is described. Referred to 1 W of net forward power, the following specific absorption rate (SAR) data were obtained: at 835.62 MHz, 16.0 Ϯ 2.5 mW/kg (mean ϮSD) with range (11-22); at 2450 MHz, 245 Ϯ 50 mW/kg with range (130 -323). Radio-frequency interference from an RTL driven at roughly 100 W is so low as to be compatible with a cellular base station only 500 m distant. To avoid potential confounding by temperature differences among as many as 144 T-75 flasks distributed over 9 RTLs (six irradiates and three shams), temperature within all flasks was controlled to 37.0 Ϯ 0.3 ºC. Experience with over two years of trouble-free operation suggests that the RTL offers a robust, logistically friendly, and environmentally satisfactory solution to the problem of large-scale in vitro experiments in bioelectromagnetics. Bioelectromagnetics 20: 65-80, 1999.

A practical method to determine the heating and cooling curves of x-ray tube assemblies with rotating anode x-ray tube is proposed. Available procedures to obtain these curves as described in the literature are performed during operation of the equipment, and the precision of the method depends on the knowledge of the total energy applied in the system. In the present work we describe procedures which use a calorimetric system and do not require the operation of the x-ray equipment. The method was applied successfully to a x-ray tube assembly that was under test in our laboratory.

A Monte Carlo computer program has been developed for the study of anti-scatter grids used in diagnostic radiology. The program estimates the scatter from soft tissue phantoms representative of either adult or paediatric examinations and uses dose increase, signal-to-noise ratio improvement and contrast improvement factors to study grid performance. It has been used to quantify the advantage of replacing grids with aluminium covers and interspaces by grids using materials of low atomic number for these components. Two approaches are used. First, the aluminium and low atomic number alternatives are compared for five grid ratios at fixed strip density and width and for tube potentials of 50, 70, 100 and 150 kV. Second, 44 commercially available grids are compared for three different imaging situations (lumbar spine, chest and paediatric). The results demonstrate that grids made with carbon fibre cover and cotton fibre interspace result in greater improvements in contrast and signal-to-noise ratio, and lower dose increase factors, than do grids made with aluminium. The dose reduction varies with irradiation conditions and is generally larger at lower tube potentials, higher grid ratios and lower strip densities. A typical reduction in mean absorbed dose in the patient is 30% in an adult lumbar spine (AP view) at 70 kV with a grid with 36 strips per centimetre and ratio 12.

Objective: To compare the properties of a new speed group F intra-oral X-ray ®lm with those of three well established types both from groups D and E, and evaluate the impact of six commercially available processing solutions. Methods: Four types of dental X-ray ®lm, Flow (Flow X-ray, West Hempstead, NY, USA), speed group F, Ektaspeed Plus (Eastman Kodak, Rochester NY, USA) and M2 Comfort (AgfaGevaert, Morstel, Belgium), both speed group E, and Ultra-speed (Eastman Kodak), speed group D, were exposed under standardised conditions and processed in six dierent processing solutions. Base plus fog density, characteristic curves, ®lm density, speed, average gradient, contrast and latitude and spatial resolution were calculated. Results: The choice of processing chemistry aected radiographic characteristics including speed grouping. The new F ®lm was consistently the fastest. M2 Comfort could achieve F speed and Ultra-speed achieved E speed using Automat XR chemicals. The speed of Ektaspeed Plus was independent of the automatic processing solution used. Ultra-Speed ®lm had the lowest base plus fog density and the widest latitude. Film contrast was similar irrespective of the ®lm and solution combination. Conclusions: The choice of processing chemistry can aect radiographic characteristics. The new F ®lm reduces patient exposure by one-half compared with E speed ®lm with no detriment to image quality.