Neoteric advancements in TB diagnostics and its future frame

Tuberculosis (TB) is one of the major infectious disease that causes threat to human health and leads to death in most of the cases. Mycobacterium tuberculosis is the causative agent that can affect both pulmonary and extra pulmonary regions of the body. This infection can be presented either as an active or latent form in the patients. Although this disease has been declared curable and preventable by WHO, it still holds its position as a global emergency. Over the past decade many hurdles such as low immunity, co-infections like HIV, autoimmune disorders, poverty, malnutrition and emerging trends in drug resistance patterns are hindering the eradication of this infection. However, many programmes have been launched by WHO with involvement of governments at various level to put a full stop over the disease. Under the Revised National Tuberculosis Control Programme (RNTCP) which was recently renamed as National Tuberculosis Elimination Programme (NTEP), the major focus is on eliminating tuberculosis by the year 2025. The main aim of the programme is to identify feasible quality testing, evaluate through NIKSHYA poshak yozana, restrict through BCG vaccination and assemble with public awareness to eradicate MTB. Numerous novel diagnostic techniques and molecular tools have been developed to elucidate and differentiate report of various suspected and active tuberculosis patients. However, improvements are still required to cut short the duration of the overall process ranging from screening of patients to their successful treatment.

Long-term medical imaging use in children with central nervous system tumors

BACKGROUND

Children with central nervous system (CNS) tumors undergo frequent imaging for diagnosis and follow-up, but few studies have characterized longitudinal imaging patterns. We described medical imaging in children before and after malignant CNS tumor diagnosis.

PROCEDURE

We conducted a retrospective cohort study of children aged 0-20 years diagnosed with CNS tumors between 1996-2016 at six U.S. integrated healthcare systems and Ontario, Canada. We collected computed topography (CT), magnetic resonance imaging (MRI), radiography, ultrasound, nuclear medicine examinations from 12 months before through 10 years after CNS diagnosis censoring six months before death or a subsequent cancer diagnosis, disenrollment from the health system, age 21 years, or December 31, 2016. We calculated imaging rates per child per month stratified by modality, country, diagnosis age, calendar year, time since diagnosis, and tumor grade.

RESULTS

We observed 1,879 children with median four years follow-up post-diagnosis in the U.S. and seven years in Ontario, Canada. During the diagnosis period (±15 days of diagnosis), children averaged 1.10 CTs (95% confidence interval [CI] 1.09-1.13) and 2.14 MRIs (95%CI 2.12-2.16) in the U.S., and 1.67 CTs (95%CI 1.65-1.68) and 1.86 MRIs (95%CI 1.85-1.88) in Ontario. Within one year after diagnosis, 19% of children had ≥5 CTs and 45% had ≥5 MRIs. By nine years after diagnosis, children averaged one MRI and one radiograph per year with little use of other imaging modalities.

CONCLUSIONS

MRI and CT are commonly used for CNS tumor diagnosis, whereas MRI is the primary modality used during surveillance of children with CNS tumors.

Deep Learning Application in Spinal Implant Identification

STUDY DESIGN

Retrospective observational study.

OBJECTIVE

To demonstrate the clinical usefulness of deep learning by identifying previous spinal implants through application of deep learning.

SUMMARY OF BACKGROUND DATA

Deep learning has recently been actively applied to medical images. However, despite many attempts to apply deep learning to medical images, the application has rarely been successful. We aimed to demonstrate the effectiveness and usefulness of deep learning in the medical field. The goal of this study was to demonstrate the clinical usefulness of deep learning by identifying previous spinal implants through application of deep learning.

METHODS

For deep learning algorithm development, radiographs were retrospectively obtained from clinical cases in which the patients had lumbar spine one-segment instrument surgery. A total of 2894 lumbar spine anteroposterior (AP: 1446 cases) and lateral (1448 cases) radiographs were collected. Labeling work was conducted for five different implants. We conducted experiments using three deep learning algorithms. The traditional deep neural network model built by coding the transfer learning algorithm, Google AutoML, and Apple Create ML. Recall (sensitivity) and precision (specificity) were measured after training.

RESULTS

Overall, each model performed well in identifying each pedicle screw implant. In conventional transfer learning, AP radiography showed 97.0% precision and 96.7% recall. Lateral radiography showed 98.7% precision and 98.2% recall. In Google AutoML, AP radiography showed 91.4% precision and 87.4% recall; lateral radiography showed 97.9% precision and 98.4% recall. In Apple Create ML, AP radiography showed 76.0% precision and 73.0% recall; lateral radiography showed 89.0% precision and 87.0% recall. In all deep learning algorithms, precision and recall were higher in lateral than in AP radiography.

CONCLUSION

The deep learning application is effective for spinal implant identification. This demonstrates that clinicians can use ML-based deep learning applications to improve clinical practice and patient care.Level of Evidence: 3.

Phenotypes and personalized medicine in the acute respiratory distress syndrome

Although the acute respiratory distress syndrome (ARDS) is well defined by the development of acute hypoxemia, bilateral infiltrates and non-cardiogenic pulmonary edema, ARDS is heterogeneous in terms of clinical risk factors, physiology of lung injury, microbiology, and biology, potentially explaining why pharmacologic therapies have been mostly unsuccessful in treating ARDS. Identifying phenotypes of ARDS and integrating this information into patient selection for clinical trials may increase the chance for efficacy with new treatments. In this review, we focus on classifying ARDS by the associated clinical disorders, physiological data, and radiographic imaging. We consider biologic phenotypes, including plasma protein biomarkers, gene expression, and common causative microbiologic pathogens. We will also discuss the issue of focusing clinical trials on the patient's phase of lung injury, including prevention, administration of therapy during early acute lung injury, and treatment of established ARDS. A more in depth understanding of the interplay of these variables in ARDS should provide more success in designing and conducting clinical trials and achieving the goal of personalized medicine.

Preoperative and Postoperative Sitting Radiographs for Adult Spinal Deformity Surgery: Upper Instrumented Vertebra Selection Using Sitting C2 Plumb Line Distance to Prevent Proximal Junctional Kyphosis

STUDY DESIGN

Case-control study from a continuous series.

OBJECTIVES

To study the impact of perioperative sitting radiographs in adult spinal deformity (ASD) patients and determine whether proximal junctional kyphosis (PJK) can be prevented using preoperative sitting radiograph.

SUMMARY OF BACKGROUND DATA

Radiographic analysis of ASD comprises standing whole-spine radiography which cannot evaluate the relaxed posture without head-to-foot compensation.

METHODS

Preoperative and postoperative whole-spine standing and sitting radiographs and proximal mechanical complications in surgically treated spinal disorders with a minimum of 1-year follow-up were studied. Whole-spinal alignment was defined by cervical lordosis (CL), sagittal vertical axis (SVA), T1 slope (T1S), thoracic kyphosis (TK), lumbar lordosis (LL), pelvic incidence (PI), pelvic tilt (PT), sacral slope (SS), and level of kyphotic apex (KA). Proximal mechanical complication was described as a PJK (proximal junctional angle >20°) or reoperation due to proximal junctional failure.

RESULTS

Surgically treated 113 patients were prospectively investigated. Patients were divided into either the ASD (thoracic to ilium posterior corrective fusion), or non-ASD groups. In the ASD group, 10 patients had postoperative PJK, and three revision surgeries were carried out due to PJF with neurological deficit. Comparing standing with sitting positions, CL, TK, and PT became larger, SVA became frontal, LL and SS became smaller, and KA became caudal particularly in the ASD group. Logistic regression analysis demonstrated that the most influenced plumb line for PJK was the upper instrumented vertebra (UIV) to C2 plumb line distance, with a cutoff value of 115 mm for predicting PJK.

CONCLUSION

Our findings highlight the usefulness of sitting spinal alignment evaluation, particularly in ASD patients, with maximum effort of thoracic spine and lower extremity compensation at standing. Mechanical complications such as PJK could be predicted using the distance from the planned UIV to the C2 plumb line in preoperative sitting radiographs.

LEVEL OF EVIDENCE

3.

[Minimally invasive autopsy: the added value of postmortem radiology]

Today, the postmortem is primarily used to evaluate the quality of the care delivered. It is therefore a cause for concern that over past decades the number of postmortems that have been carried out has been declining. One of the reasons for this is the increased attention being paid to the physical integrity of the deceased by physicians and next of kin. However, a large number of studies show that 10-25% of post-mortems reveal a discrepancy between the clinical findings and the results of the postmortem. Postmortem radiological investigations make a minimally-invasive postmortem possible. In a number of cases, the diagnostic value of postmortem radiological investigation approaches that of the postmortem. Various studies show that postmortem radiological investigation has additional value, however, it also entails higher costs and logistical problems. The question is to what extent the Dutch healthcare system is prepared to go to implement this new development?

The Applications of Radiomics in Precision Diagnosis and Treatment of Oncology: Opportunities and Challenges

Medical imaging can assess the tumor and its environment in their entirety, which makes it suitable for monitoring the temporal and spatial characteristics of the tumor. Progress in computational methods, especially in artificial intelligence for medical image process and analysis, has converted these images into quantitative and minable data associated with clinical events in oncology management. This concept was first described as radiomics in 2012. Since then, computer scientists, radiologists, and oncologists have gravitated towards this new tool and exploited advanced methodologies to mine the information behind medical images. On the basis of a great quantity of radiographic images and novel computational technologies, researchers developed and validated radiomic models that may improve the accuracy of diagnoses and therapy response assessments. Here, we review the recent methodological developments in radiomics, including data acquisition, tumor segmentation, feature extraction, and modelling, as well as the rapidly developing deep learning technology. Moreover, we outline the main applications of radiomics in diagnosis, treatment planning and evaluations in the field of oncology with the aim of developing quantitative and personalized medicine. Finally, we discuss the challenges in the field of radiomics and the scope and clinical applicability of these methods.

Translation of morphological and functional musculoskeletal imaging

In an effort to develop quantitative biomarkers for degenerative joint disease and fill the void that exists for diagnosing, monitoring, and assessing the extent of whole joint degeneration, the past decade has been marked by a greatly increased role of noninvasive imaging. This coupled with recent advances in image processing and deep learning opens new possibilities for promising quantitative techniques. The clinical translation of quantitative imaging was previously hampered by tedious non-scalable and subjective image analysis. Osteoarthritis (OA) diagnosis using X-rays can be automated by the use of deep learning models and pilot studies showed feasibility of using similar techniques to reliably segment multiple musculoskeletal tissues and detect and stage the severity of morphological abnormalities in magnetic resonance imaging (MRI). Automation and more advanced feature extraction techniques have applications on larger more heterogeneous samples. Analyses based on voxel based relaxometry have shown local patterns in relaxation time elevations and local correlations with outcome variables. Bone cartilage interactions are also enhanced by the analysis of three-dimensional bone morphology and the potential for the assessment of metabolic activity with simultaneous Positron Emission Tomography (PET)/MR systems. Novel techniques in image processing and deep learning are augmenting imaging to be a source of quantitative and reliable data and new multidimensional analytics allow us to exploit the interactions of data from various sources. In this review, we aim to summarize recent advances in quantitative imaging, the application of image processing and deep learning techniques to study knee and hip OA. ©2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res XX:XX-XX, 2018.

Review of 2-D/3-D Reconstruction Using Statistical Shape and Intensity Models and X-Ray Image Synthesis: Toward a Unified Framework

Patient-specific three-dimensional (3-D) bone models are useful for a number of clinical applications such as surgery planning, postoperative evaluation, as well as implant and prosthesis design. Two-dimensional-to-3-D (2-D/3-D) reconstruction, also known as model-to-modality or atlas-based 2-D/3-D registration, provides a means of obtaining a 3-D model of a patient's bones from their 2-D radiographs when 3-D imaging modalities are not available. The preferred approach for estimating both shape and density information (that would be present in a patient's computed tomography data) for 2-D/3-D reconstruction makes use of digitally reconstructed radiographs and deformable models in an iterative, non-rigid, intensity-based approach. Based on a large number of state-of-the-art 2-D/3-D bone reconstruction methods, a unified mathematical formulation of the problem is proposed in a common conceptual framework, using unambiguous terminology. In addition, shortcomings, recent adaptations, and persisting challenges are discussed along with insights for future research.

Optical and x-ray technology synergies enabling diagnostic and therapeutic applications in medicine

X-ray and optical technologies are the two central pillars for human imaging and therapy. The strengths of x-rays are deep tissue penetration, effective cytotoxicity, and the ability to image with robust projection and computed-tomography methods. The major limitations of x-ray use are the lack of molecular specificity and the carcinogenic risk. In comparison, optical interactions with tissue are strongly scatter dominated, leading to limited tissue penetration, making imaging and therapy largely restricted to superficial or endoscopically directed tissues. However, optical photon energies are comparable with molecular energy levels, thereby providing the strength of intrinsic molecular specificity. Additionally, optical technologies are highly advanced and diversified, being ubiquitously used throughout medicine as the single largest technology sector. Both have dominant spatial localization value, achieved with optical surface scanning or x-ray internal visualization, where one often is used with the other. Therapeutic delivery can also be enhanced by their synergy, where radio-optical and optical-radio interactions can inform about dose or amplify the clinical therapeutic value. An emerging trend is the integration of nanoparticles to serve as molecular intermediates or energy transducers for imaging and therapy, requiring careful design for the interaction either by scintillation or Cherenkov light, and the nanoscale design is impacted by the choices of optical interaction mechanism. The enhancement of optical molecular sensing or sensitization of tissue using x-rays as the energy source is an important emerging field combining x-ray tissue penetration in radiation oncology with the molecular specificity and packaging of optical probes or molecular localization. The ways in which x-rays can enable optical procedures, or optics can enable x-ray procedures, provide a range of new opportunities in both diagnostic and therapeutic medicine. Taken together, these two technologies form the basis for the vast majority of diagnostics and therapeutics in use in clinical medicine.

[Frequency and doses of diagnostic and interventional X‑ray applications : Trends between 2007 and 2014]

BACKGROUND

In Germany, approximately 95% of man-made radiation exposure of the population results from diagnostic and interventional X‑ray procedures. Thus, radiation protection of patients in this field of application is of great importance.

OBJECTIVE

Quantification and evaluation of current data on the frequency and doses of X‑ray procedures as well as temporal trends for the years 2007-2014.

MATERIAL AND METHODS

For outpatients the frequency of X‑ray procedures was estimated using reimbursement data from health insurances and for inpatients by means of hospital statistics. For the years under review, representative values for the effective dose per X‑ray application were determined mainly from data reported by X‑ray departments to the competent authorities.

RESULTS

In 2014 approximately 140 million X‑ray procedures were performed in Germany with some 40% from dental examinations. On average 1.7 procedures per inhabitant and year were almost constantly carried out between 2007 and 2014. Besides dental diagnostics, X‑ray examinations of the skeleton and thorax were performed most frequently. The number of computed tomography (CT) examinations increased by approximately 40%. The increase in magnetic resonance imaging (MRI) was even more pronounced with approximately 55% but overall CT examinations were still performed more often than MRI. The doses per X‑ray procedure were only slightly reduced, despite the various dose reduction approaches established in recent years; therefore, the mean effective dose per inhabitant increased from approximately 1.4 mSv in 2007 to 1.6 mSv in 2014, mainly due to the increasing frequency of CT examinations.

CONCLUSION

The principles of justification and optimization of radiological procedures are to be consistently applied in each individual instance, especially in the case of CT examinations.

The S Sign: A New Radiographic Tool to Aid in the Diagnosis of Slipped Capital Femoral Epiphysis

BACKGROUND

Children with slipped capital femoral epiphysis (SCFE) are often seen by an array of medical professionals prior to diagnosis. Patients with mild slips, slips with knee pain, or bilateral slips can occasionally present a diagnostic challenge that increases the risk of a delay in diagnosis and associated complications.

OBJECTIVES

This study introduces a new radiographic parameter, which we refer to as the S-sign, and analyzes its diagnostic utility on a frog-leg lateral radiograph.

METHODS

Twenty observers reviewed the radiographs from 35 patients with SCFE using Klein's line on anteroposterior pelvis radiographs and the S-sign on frog-leg lateral radiographs to diagnose an SCFE. Analysis included diagnostic outcomes and intraobserver and interobserver reliability.

RESULTS

The S-sign was more accurate at identifying an SCFE compared with Klein's line (92.4% vs. 79.2%, respectively). Sensitivity and specificity was greater for the S-sign compared with Klein's line (89.0% and 95.2% vs. 68.3% and 89.0%, respectively). A combination of the S-sign and Klein's line yielded a sensitivity of 96.5% and a specificity of 85.0%. The combination of tests was more diagnostic for an SCFE, compared with using the Klein's line, which was statistically significant (p < 0.001).

CONCLUSIONS

With increased awareness of the S-sign and a usage of the combined test, clinicians can more reliably and accurately diagnose an SCFE. Clinicians are more likely to diagnose an SCFE using the combined test, compared with solely relying on Klein's line, which we found to be statistically significant.

Emergency Room Plain Radiograph Imaging Study Indications: An Analysis of Quality and Trends at a Large Academic Medical Center

RATIONALE AND OBJECTIVES

This study aimed to assess the quality of and analyze trends among clinical indications received for emergency room radiograph studies.

MATERIALS AND METHODS

Clinical indications provided by the emergency room and rapid care for consecutive chest, abdominal, and musculoskeletal radiographs were reviewed. Chart review was performed to analyze the provided indications compared to clinical information known to the ordering providers. Chest and abdominal radiograph indications were graded according to symptoms and physical examination signs and relevant past medical history. Musculoskeletal indications were graded according to symptoms, mechanism of injury, and positive physical examination findings. Each study indication was graded on a scale from 0 to 2 according to scales modified from those of prior published studies. Grades were further stratified according to ordering location, time of shift, ordering provider level, and specific anatomy involved.

RESULTS

For chest and abdomen studies, mean scores for symptom and physical examination and provided past medical history grades were 1.16 and 0.36, respectively. There was a trend toward a significant difference in mean medical history grades among ordering provider levels. For musculoskeletal studies, mean scores for symptom, mechanism, and physical examination grades were 1.04, 0.89, and 0.51, respectively. Mean symptom and examination grades for physician extenders were significantly less than those of attendings and residents. Mean symptom and mechanism grades for extremity studies were significantly less than those for spinal studies.

CONCLUSIONS

For plain radiographs ordered through the emergency department, certain critical pieces of study indications tended to be underreported relative to other components. Furthermore, significant differences in select categories were seen among ordering provider levels and anatomic location.

Organ Doses From Diagnostic Medical Radiography-Trends Over Eight Decades (1930 to 2010)

This study provides a retrospective assessment of doses to 13 organs for the most common radiographic examinations conducted between the 1930s and 2010, taking into account typical technical parameters used for radiography during those years. This study is intended to be a resource on changes in medical diagnostic radiation exposure over time with a specific purpose of supporting retrospective epidemiological studies of radiation health risks. The authors derived organ doses to the brain, esophagus, thyroid, red bone marrow, lungs, breast, heart, stomach, liver, colon, urinary bladder, ovaries, and testes based on 14 common radiographic procedures and compared, when possible, with doses reported in the literature. These dose estimates were based on radiographic exposure parameters described in textbooks widely used by radiologic technologists in training from 1939 to 2010. The derived estimated doses presented here are believed to be representative of typical organs for an average-size adult who might be considered to be similar to the reference person. There were large variations in organ doses noted among the different types of radiographic examinations. Doses were highest in organs within the area imaged and next highest in organs in close proximity to the area imaged. Estimated organ doses have declined substantially [overall 22-fold (±38)] over time as a consequence of changes in technology, imaging protocols and protective measures. For some examinations, only slight differences were observed in doses for the decades of the 1960s, 1970s, and 1980s due to minor changes in technical parameters. Substantial dose reductions were observed in the 1990s and 2000s.

[PECULIARITY OF NATIONAL TUBERCULOSIS PROGRAM, JAPAN--Public-Private Mix from the Very Beginning, and Provision of X-ray Apparatus in Most General Practitioner's Clinics]

Modern National Tuberculosis Program (NTP) of Japan started in 1951 when Tuberculosis (TB) Control Law was legislated, and 3 major components were health examination by tuberculin skin test (TST) and miniature X-ray, BCG vaccination and extensive use of modern TB treatment. As to the treatment program, Japan introduced Public-Private Mix (PPM) from the very beginning, and major reasons why PPM was adopted are (1) TB was then highly prevalent (Table 1), (2) TB sanatoria where many specialists are working are located in remote inconvenient places due to stigma against TB, (3) health centers (HCs) in Japan are working exclusively on prophylactic activities, and minor exceptions are treatment of sexually transmitted diseases and artificial pneumothorax for TB cases, however, as it covers on the average 100,000 population, access is not so easy in rural area, (4) Out-patients clinics mainly operated by general practitioners (GPs) are located throughout Japan, and the access is easy. Methods of TB treatment was developing rapidly in early 1950s, however, in 1952, as shown in Table 2, artificial pneumothorax and peritoneum were still used in many cases, and to fix the dosage of refill air, fluoroscopy was needed. Hence, GPs treating TB under TB Control Law had to be equipped with X-ray apparatus. To maintain the quality of TB treatment, "Criteria for TB treatment" was provided and revised taking into consideration the progress in TB treatment. If applied methods of treatment fit with the above criteria, public support is made for the cost of TB treatment. To discuss the applied treatment, TB Advisory Committee was set in each HC, composing of 5 members, director of HC, 2 TB specialists and 2 doctors recommended by the local medical association. In 1953, the first TB prevalence survey using stratified random sampling method was carried out, and the prevalence of TB requiring treatment was estimated at 3.4%, and only 21% of found cases knew their own disease, and more than half of all TB were found above 30 years of age. Based on these results, mass screening was expanded to cover whole population in 1955, and since 1957, cost of mass screening and BCG vaccination was covered 100% by public fund. Unified TB registration system covering whole Japan was introduced in 1961, and in the same year, national government subsidy for the hospitalization of infectious TB cases was raised from 50% to 80%. Hence, Japan succeeded to organize PPM system in TB care, and with 10% annual decline of TB, in 1975, Japan moved into the TB middle prevalence country.

Dose surveys and DRLs: critical look and way forward

The main purpose of dose surveys has been to detect and bring down wide variation in radiation doses for any particular radiological examination and to avoid doses that are on higher side. Diagnostic reference levels (DRLs) have been used for over two decades as an aid in this objective. With very limited success that has been achieved through DRL, the author has recently described a new term 'acceptable quality dose' (AQD) that is aimed at optimisation within the DRL, is facility initiated and takes into account all three important parameters-image quality, dose and patient's body build. It is hoped that AQD will be found easy to establish, will be a useful tool to achieve optimisation in the facilities and will serve as the standard dose.

Hospitalization for cancer among radiologists in Taiwan

BACKGROUND

Population aging and the incremental use of high-tech instruments increase the demand for radiological examinations and treatments in medical services. The exposure of radiologists and other medical workers to medical treatment radiation may thus be increased.

OBJECTIVES

The aim of the study was to explore the average number of cancer hospitalizations and use of hospitalization as cancer treatment for radiologists compared with that for family medicine physicians, as well as the trends in the annual average number of cancer hospitalizations among radiologists.

METHODS

Research data were obtained from the 2000-2010 Taiwan National Health Insurance Research Database. These samples collected for this study were unbalanced panel data.

RESULTS

The average number of cancer hospitalizations for radiologists from 2000 to 2010 ranged between 3.67 and 28.26‰. After controlling the effects of gender, age, hospital accreditation level and year using generalized estimating equations with a binomial distribution and logit link function, our study found that radiologists had non significant higher risk of cancer hospitalizations compared with family medicine physicians. However, the average number of cancer hospitalizations for radiologists showed an annual decline from 2000 to 2010.

CONCLUSIONS

Compared with family medicine physicians, radiologists had non significant higher risk of cancer hospitalizations. The data period examined in this study was only 11 years. Considering the numerous new radiological procedures currently in use in modern medical treatments, the health status of medical radiation workers should be continuously monitored in the future.

Assessing Lower Limb Alignment: Comparison of Standard Knee Xray vs Long Leg View

BACKGROUND

High tibial osteotomy (HTO) is a well-established and commonly utilized technique in medial knee osteoarthritis secondary to varus malalignment. Accurate measurement of the preoperative limb alignment, and the amount of correction required are essential when planning limb realignment surgery. The hip-knee-ankle angle (HKA) measured on a full length weightbearing (FLWB) X-ray in the standing position is considered the gold standard, since it allows for reliable and accurate measurement of the mechanical axis of the whole lower extremity. In general practice, alignment is often evaluated on standard anteroposterior weightbearing (APWB) X-rays, as the angle between the femur and tibial anatomic axis (TFa). It is, therefore, of value to establish if measuring the anatomical axis from limited APWB is an effective measure of knee alignment especially in patients undergoing osteotomy about the knee.

METHODS

Three independent observers measured preoperative and postoperative FTa with standard method (FTa1) and with circles method (FTa2) on APWB X-ray and the HKA on FLWB X-ray at three different time-points separated by a two-week period. Intra-observer and inter-observer reliabilities and the comparison and relationship between anatomical and mechanical alignment were calculated.

RESULTS

Intra- and interclass coefficients for all the three methods indicated excellent reliability, having all the values above 0.80. Using the mean of paired t-student test, the comparison of HKA versus TFa1 and TFa2 showed a statistically significant difference (p<.0001) both for the pre-operative and post-operative sets of values. The correlation between the HKA and FTal was found poor for the preoperative set (R=0.26) and fair for the postoperative one (R=0.53), while the new circles method showed a higher correlation in both the preoperative (R=0.71) and postoperative sets (R=0.79).

CONCLUSIONS

Intra-observer reliability was high for HKA, FTal and FTa2 on APWB x-rays in the pre- and post-operative setting. Inter-rater reliability was higher for HKA and TFa2 compared to FTal. The femoro-tibial angle as measured on APWB with the traditional method (FTal) has a weak correlation with the HKA, and based on these findings, should not be used in everyday practice. The FTa2 showed better correlation with the HKA, although not excellent.

LEVEL OF EVIDENCE

Level III, Retrospective study.

Estimation of the collective dose in the Portuguese population due to medical procedures in 2010

In a wide range of medical fields, technological advancements have led to an increase in the average collective dose in national populations worldwide. Periodic estimations of the average collective population dose due to medical exposure is, therefore of utmost importance, and is now mandatory in countries within the European Union (article 12 of EURATOM directive 97/43). Presented in this work is a report on the estimation of the collective dose in the Portuguese population due to nuclear medicine diagnostic procedures and the Top 20 diagnostic radiology examinations, which represent the 20 exams that contribute the most to the total collective dose in diagnostic radiology and interventional procedures in Europe. This work involved the collaboration of a multidisciplinary taskforce comprising representatives of all major Portuguese stakeholders (universities, research institutions, public and private healthcare providers, administrative services of the National Healthcare System, scientific and professional associations and private service providers). This allowed us to gather a comprehensive amount of data necessary for a robust estimation of the collective effective dose to the Portuguese population. The methodology used for data collection and dose estimation was based on European Commission recommendations, as this work was performed in the framework of the European wide Dose Datamed II project. This is the first study estimating the collective dose for the population in Portugal, considering such a wide national coverage and range of procedures and consisting of important baseline reference data. The taskforce intends to continue developing periodic collective dose estimations in the future. The estimated annual average effective dose for the Portuguese population was of 0.080±0.017 mSv caput(-1) for nuclear medicine exams and of 0.96±0.68 mSv caput(-1) for the Top 20 diagnostic radiology exams.

Forensic human identification in the United States and Canada: a review of the law, admissible techniques, and the legal implications of their application in forensic cases

Forensic human identification techniques are successful if they lead to positive personal identification. However, the strongest personal identification is of no use in the prosecution--or vindication--of an accused if the associated evidence and testimony is ruled inadmissible in a court of law. This review examines the U.S. and Canadian legal rulings regarding the admissibility of expert evidence and testimony, and subsequently explores four established methods of human identification (i.e., DNA profiling, forensic anthropology, forensic radiography, forensic odontology) and one complementary technique useful in determining identity, and the legal implications of their application in forensic cases.

Effective dose delivered by conventional radiology to Aosta Valley population between 2002 and 2009

OBJECTIVE

Medical diagnostic procedures can be considered the main man-made source of ionising radiation exposure for the population. Conventional radiography still represents the largest contribution to examination frequency. The present work evaluates procedure frequency and effective dose from the majority of conventional radiology examinations performed at the Radiological Department of Aosta Hospital from 2002 to 2009.

METHOD

Effective dose to the patient was evaluated by means of the software PCXMC. Data provided by the radiological information system allowed us to obtain collective effective and per caput dose.

RESULTS

The biggest contributors to per caput effective dose from conventional radiology are vertebral column, abdomen, chest, pelvis and (limited to females) breast. Vertebral column, pelvis and breast procedures show a significant dose increment in the period of the study. The mean effective dose per inhabitant from conventional radiology increased from 0.131 mSv in 2002 to 0.156 mSv in 2009. Combining these figures with those from our study of effective dose from CT (0.55 mSv in 2002 to 1.03 mSv in 2009), the total mean effective dose per inhabitant increased from 0.68 mSv to 1.19 mSv. The contribution of CT increased from 81% to 87% of the total. In contrast, conventional radiology accounts for 85% of the total number of procedures, but only 13% of the effective dose.

CONCLUSION

The study has demonstrated that conventional radiography still represents the biggest contributor to examination frequency in Aosta Valley in 2009. However, the frequency of the main procedures did not change significantly between 2002 and 2009.

Exposure of the Swiss population by medical x-rays: 2008 review

Nationwide surveys on radiation dose to the population from medical radiology are recommended in order to follow the trends in population exposure and ensure radiation protection.The last survey in Switzerland was conducted in 1998,and the annual effective dose from medical radiology was estimated to be 1 mSv y j(-1) per capita. The purpose of this work was to follow the trends in diagnostic radiology between 1998 and 2008 in Switzerland and determine the contribution of different modalities and types of examinations to the collective effective dose from medical x-rays. For this reason, an online database(www.raddose.ch) was developed. All healthcare providers who hold a license to run an x-ray unit in the country were invited to participate in the survey. More than 225 examinations, covering eight radiological modalities, were included in the survey. The average effective dose for each examination was reassessed. Data from about 3,500 users were collected (42% response rate). The survey showed that the annual effective dose was 1.2 mSv/capita in 2008. The most frequent examinations are conventional and dental radiographies (88%). The contribution of computed tomography was only 6% in terms of examination frequency but 68% in terms of effective dose. The comparison with other countries showed that the effective dose per capita in Switzerland was in the same range as in other countries with similar healthcare systems, although the annual number of examinations performed in Switzerland was higher.

Forensic radiography: an overview

Perhaps the first instance of forensic radiography occurred in the 1890s when Professor AW Wright of Yale University tested Wilhelm Roentgen's newly discovered x-ray photography on a deceased rabbit. Of interest were small, round objects inside the rabbit that appeared as dark spots on the positive film. The objects were extracted and identified as bullets, thereby helping to determine the cause of the rabbit's death. In the years since Roentgen's discovery, the use of radiography and other medical imaging specialties to aid in investigating civil and criminal matters has increased as investigators realize how radiologic technology can yield information that otherwise is unavailable. Radiologic technologists can play a key role in forensic investigations.

Nationwide surveys of chest, abdomen, lumbosacral spine radiography, and upper gastrointestinal fluoroscopy: a summary of findings

This paper reports findings from Nationwide Evaluation of X-ray Trends surveys conducted in 2001, 2002, and 2003 of clinical facilities that perform routine radiographic examinations of the adult chest, abdomen, lumbosacral spine, and upper gastrointestinal fluoroscopic examinations. Randomly identified clinical facilities were surveyed in approximately 40 participating states. For the surveyed radiographic exams, additional facilities that use computed radiography or digital radiography were surveyed to ensure adequate sample sizes for determining comparative statistics. State radiation control personnel performed site visits and collected data on patient exposure, radiographic/fluoroscopic technique factors, image quality, and quality-control and quality-assurance practices. Results of the NEXT surveys are compared with those of previous surveys conducted in 1964 and 1970 by the U.S. Public Health Service and the Food and Drug Administration. An estimated 155 million routine adult chest exams were performed in 2001. Average patient entrance skin air kerma from chest radiography at facilities using digital-based imaging modalities was found to be significantly higher (p < 0.001), but not so for routine abdomen or lumbosacral spine radiography. Digital-based imaging showed a substantial reduction in patient exposure for the radiographic portion of the routine upper gastrointestinal fluoroscopy exam. Long-term trends in surveyed diagnostic examinations show that average patient exposures are at their lowest levels. Of concern is the observation that a substantial fraction of surveyed non-hospital sites indicated they do not regularly have a medical physics survey conducted on their radiographic equipment. These facilities are likely unaware of the radiation doses they administer to their patients.

[Imagery and orthodontics: trends, present and future]

From the first dental image in 1895 and the first image of the head in 1896 by Otto Walkhoff to 3D modern cephalic assessment there has been a continuous evolution in imaging techniques. Digital cephalic volume data processing allows 2D and 3D reformations in accordance with morphologic, topographic and biodimensional anatomic needs. In France, Jacques Treil demonstrated its application in cephalometry through his CT scan research. The transcription of European Directives to national laws leads to rigorous radioprotection measures. The worldwide spread of cone beam technique devoted specifically to dentomaxillofacial imaging should now reduce the reluctance of orthodontists to provide radiological examinations to children by significantly reducing radiation exposure. This is certainly the technique of the future.

Update on the diagnostic radiology employment market: findings through 2006-2007

PURPOSE

To describe the employment market for diagnostic radiologists in 2006-2007, with attention to differences among subspecialties.

METHODS

The authors conducted the most recent in a series of annual surveys of vacancies in academic departments and obtained data from the placement service of the American College of Radiology (ACR), its Professional Bureau, during its operation at the annual meeting of the Radiological Society of North America. The two data series were correlated. The percentage of academic vacancies in each subspecialty was compared with the percentage of academic radiologists in that subspecialty.

RESULTS

Job listings per job seeker at the placement service, which serves both community and academic positions, were 0.72 for 2007 compared with approximately 1.1 to 1.2 for 2003 to 2006 and variation from 0.25 to 3.8 in the preceding decade. The correlation of the two data series was 0.84 (P = .08) for the 5 years for which both are available. Particularly high ratios of academic vacancies to academic radiologists were found for interventional radiology and breast imaging; particularly low ratios were found for neuroradiology and nuclear radiology.

CONCLUSIONS

The job market remains very much intermediate between the highs and lows that have occurred since 1990, but finding highly desirable jobs is likely to be somewhat more difficult, and filling vacancies somewhat easier, in 2007 than in the past few years. Interventional radiology and breast imaging are the subspecialties in which academic positions are most difficult to fill; neuroradiology and nuclear radiology seem to be at the opposite end of the spectrum. The same differences across subspecialties are probably found in community practice, given the strong correlation of the two data series.

Characterization of radiologists' search strategies for lung nodule detection: slice-based versus volumetric displays

The goal of this study was to assess whether radiologists' search paths for lung nodule detection in chest computed tomography (CT) between different rendering and display schemes have reliable properties that can be exploited as an indicator of ergonomic efficiency for the purpose of comparing different display paradigms. Eight radiologists retrospectively viewed 30 lung cancer screening CT exams, containing a total of 91 nodules, in each of three display modes [i.e., slice-by-slice, orthogonal maximum intensity projection (MIP) and stereoscopic] for the purpose of detecting and classifying lung nodules. Radiologists' search patterns in the axial direction were recorded and analyzed along with the location, size, and shape for each detected feature, and the likelihood that the feature is an actual nodule. Nodule detection performance was analyzed by employing free-response receiver operating characteristic methods. Search paths were clearly different between slice-by-slice displays and volumetric displays but, aside from training and novelty effects, not between MIP and stereographic displays. Novelty and training effects were associated with the stereographic display mode, as evidenced by differences between the beginning and end of the study. The stereo display provided higher detection and classification performance with less interpretation time compared to other display modes tested in the study; however, the differences were not statistically significant. Our preliminary results indicate a potential role for the use of radiologists' search paths in evaluating the relative ergonomic efficiencies of different display paradigms, but systematic training and practice is necessary to eliminate training curve and novelty effects before search strategies can be meaningfully compared.

Do emergency medicine physicians perform ultrasound and conventional radiography in the emergency department? Recent trends from 1993 to 2001

PURPOSE

To examine trends in emergency medicine physicians' participation in diagnostic ultrasound and conventional radiography from 1993 to 2001.

METHODS AND MATERIALS

The nationwide Medicare Part B Physician/Supplier Procedure Summary Master Files for 1993 and 1996 through 2001 were examined to determine the total number of ultrasound and conventional radiography examinations performed in emergency departments, except for ophthalmic ultrasound and supervision or interpretation claims. Ultrasound examinations were categorized as general, vascular, breast, echocardiography, and obstetrical. Conventional x-ray examinations were categorized as chest, skeletal, abdomen, and gastrointestinal fluoroscopy. The total volume and overall share of the two modalities and nine aforementioned categories were calculated for each year for radiologists, emergency medicine physicians, other nonradiologists, and multispecialty groups using the Medicare provider and location-of-service codes.

RESULTS

The total volume of ultrasound examinations performed in emergency departments increased from 134,533 in 1993 to 355,889 in 2001 (+164.5%). Emergency medicine physicians performed 760 (0.6%) of the examinations in 1993 and 1160 (0.3%) in 2001. Radiologists performed 87,377 (64.9%) in 1993 and 257,479 (72.3%) in 2001, other nonradiologists (primarily cardiologists performing echocardiography and vascular surgeons performing vascular ultrasound) performed 40,501 (30.1%) in 1993 and 76,649 (21.5%) in 2001, and multispecialty groups performed 5895 (4.4%) in 1993 and 20,601 (5.8%) in 2001. The total volume of conventional radiography examinations increased from 5,120,608 in 1993 to 8,054,771 (+57.3%) in 2001. Emergency medicine physicians performed 243,705 examinations (4.8%) in 1993 and 167,968 (2.1%) in 2001, radiologists performed 4,558,933 (89.0%) and 7,478,659 (92.8%), other nonradiologists performed 113,848 (2.2%) and 99,627 (1.2%), and multispecialty groups performed 204,122 (4.0%) and 308,517 (3.8%). The largest volume of examinations performed by radiologists and emergency medicine physicians in emergency departments in 2001 was in chest radiography, with radiologists performing 3,765,209 and emergency medicine physicians performing 98,851. The largest volume for other nonradiologists in emergency departments in 2001 was in echocardiography; they performed 53,943 of these examinations.

CONCLUSION

Emergency medicine physicians perform a very small percentage of all ultrasound and conventional x-ray examinations performed in emergency departments, with their share decreasing over the 8-year period. The fact that the participation of emergency medicine physicians in ultrasound imaging and conventional radiography in emergency departments is limited and has been decreasing makes their claim of substantial participation highly questionable.

Vehicles, containers, railway wagons

PURPOSE

Findings shall be shown which have been obtained employing X-rays, accelerator rays and gamma rays for control.

MATERIAL AND METHOD

The observations have been made with transmission imaging, backscatter imaging, and with the combination of transmission with backscatter imaging. The images come from the manufacturers and from personal collections.

RESULTS

One has to look for the extra spaces room, which are often hidden and for the objects themselves.

CONCLUSION

Weapons, explosive, cigarettes, drugs and other contraband can be found. The smugglers react to possible controls with X-rays. The controls of the future will combine different technologies.

Search by X-rays applied technology

X-rays and gamma-rays are part of different methods of imaging for control purpose. The main and most widely used method is conventional fluoroscopy with transmission images. Dual energy imaging, backscatter imaging and computed tomography allow visualizing of interesting items or of single layers without superposition; these methods have been developed recently or have been adapted to imaging for security reasons. Dual energy uses the specific absorption characteristics of a substance. Spectroscopy permits the identification of substances in packages or luggage, without direct access. Industry offers technical solutions which combine different methods. Comparing the different methods, one has to conclude that the disadvantage of the transmission image is due to superimposition, which limits the recognition of searched items. The combination with other methods increases the reliability of recognition. Future will bring more controls for security reasons and in consequence, more "control imaging" by X-rays. Imaging for security reasons will be combined with pattern recognition; politicians will answer the demand for security and impose more controls.

Luggage and shipped goods

PURPOSE

Control of luggage and shipped goods are frequently carried out. The possibilities of X-ray technology shall be demonstrated.

MATERIALS AND METHODS

There are different imaging techniques. The main concepts are transmission imaging, backscatter imaging, computed tomography, and dual energy imaging and the combination of different methods The images come from manufacturers and personal collections.

RESULTS

The search concerns mainly, weapons, explosives, and drugs; furthermore animals, and stolen goods, Special problems offer the control of letters and the detection of Improvised Explosive Devices (IED).

CONCLUSION

One has to expect that controls will increase and that imaging with X-rays will have their part. Pattern recognition software will be used for analysis enforced by economy and by demand for higher efficiency - man and computer will produce more security than man alone.

Search for persons

X-rays and gamma-rays are used to detect hidden persons in vehicles, containers, and railway wagons. They are produced with accelerators, X-ray tubes, cobalt 60 and caesium 137. Fan beams adjusted to a line of digital detectors produce the image. The resolution is sufficient to recognise a human being. The recognition of persons with transmission images is limited by superimposition; backscatter imaging produces clearer images but of one single layer only. The future will bring new applications of search for persons with X-rays. Crimes and terrorist attacks will induce added demand for security, where search with X-rays and gamma-rays will keep its important role or even increase it.

X-ray security scanners for personnel and vehicle control: dose quantities and dose values

After the security related occurrences in the past few years, there is an increasing need for airport security and border controls. In the combat against terror and smuggling, X-rays are used for the screening of persons and vehicles. The exposure of humans to ionising radiation raises the question of justification. To solve this question, reliable and traceable dose values are needed. A research project of the German Federal Ministry for the Environment, Nature Conservation and Nuclear Safety was initiated. Its task is to measure the ambient dose equivalent, H*(10), and the personal dose equivalent, H(p)(10), for typical types of personnel and vehicle X-ray scanners, using the transmission and/or backscatter method. In the following, the measuring quantities which are to be used for these investigations will be discussed and the measuring instruments will be presented. Furthermore, the experimental set-up is described. For the personnel X-ray scanners investigated, the obtained dose values are in the range from 0.07 to 6 microSv. These values will be compared to the dose values of the natural environmental radiation and some exposures in the field of medicine.

Shift in imaging modalities of gastrointestinal tract through 25 years and its impact on patient ionizing radiation doses

We wanted to explore the shift in modalities when diagnosing the gastrointestinal tract through the last three decades and see how this has influenced on the radiation doses given to this patient population. Activity reports from a central hospital in the years of 1979-2003 have been reviewed. The x-ray based modalities have decreased, while there has been a marked increase in colonoscopies, gastroscopies, ultrasound, and magnetic resonance cholangiopancreatography. This has caused a reduction in collective effective radiation dose of 54%.