Credentialing for radiology

Patients expect to receive safe, predictable and high-quality care delivered by competent professionals. Thus, it has become important to provide specific training in existing and new modalities and prove on-going clinical expertise. Hospital credentialing is the process by which the competence of a doctor is determined by the hospital management. In Australia, radiologists participate in a mandatory program of continuing professional development and are also required to maintain a logbook of procedures. The Conjoint Committee for the Recognition of Training in Peripheral Endovascular Therapy has been established to advise the respective subspecialty groups on the requirements for accreditation. This article examines some of the issues the committee has considered in preparing the criteria to assist institutions for the purposes of credentialing and gives an Australian perspective on future trends.

Automatic detection of lung nodule from computer tomography images

Lung nodule refers to lung tissue abnormalities that may become cancerous. An automated system that detects nodules of common sizes within lung images is developed. It consists of acquisition, pre-processing, background removal, nodule detection, and false positives reduction. The system can assist expert radiologists in their decision making.

Automatic extraction of abnormal regions from lung images

A system that could automatically extract abnormal lung regions may assist expert radiologists in verifying lung tissue abnormalities. This paper presents an automated lung nodule detection system consisting of five components: acquisition, pre-processing, background removal, detection, and false positives reduction. The system employs a combination of an ensemble classification and clustering methods. The performance of the developed system is compared against some existing counterparts. Based 011 the experimental results, the proposed system achieved a sensitivity of 100% and a false-positives/slice of 0.67 for 30 tested CT images.

Random forest based lung nodule classification aided by clustering

An automated lung nodule detection system can help spot lung abnormalities in CT lung images. Lung nodule detection can be achieved using template-based, segmentation-based, and classification-based methods. The existing systems that include a classification component in their structures have demonstrated better performances than their counterparts. Ensemble learners combine decisions of multiple classifiers to form an integrated output. To improve the performance of automated lung nodule detection, an ensemble classification aided by clustering (CAC) method is proposed. The method takes advantage of the random forest algorithm and offers a structure for a hybrid random forest based lung nodule classification aided by clustering. Several experiments are carried out involving the proposed method as well as two other existing methods. The parameters of the classifiers are varied to identify the best performing classifiers. The experiments are conducted using lung scans of 32 patients including 5721 images within which nodule locations are marked by expert radiologists. Overall, the best sensitivity of 98.33% and specificity of 97.11% have been recorded for proposed system. Also, a high receiver operating characteristic (ROC) A_z of 0.9786 has been achieved.

Central venous dialysis : an Australian survey

Aim: To explore the current central venous dialysis catheter (CVDC) nursing care practices in Australia. Method: A survey of dialysis units in Australia. Results: 66% return rate (48/73) Internal jugular is the main insertion site (75%) and the majority are tunneled (85%). Insertion was performed most commonly by radiologists (34%) followed by intensivists (24%) with one center reporting insertion by nursing staff. CVDCs were most commonly inserted in radiology (54%), followed by theatre (33%). Dressings were attended weekly (55%) or on dialysis days (45%). Chlorhexidine was the antiseptic solution of choice (54%) followed by povidine-iodine (37%). In 21% of centres Mupirocin was routinely applied in addition to the antiseptic solution. Transparent dressings were overwhelmingly favoured however most centres recommended alternatives related to patient need. 21% of units reported enrolled nurses undertaking dressings. All units reported the use of sterile gloves and sterile dressing packs. 10% reported different routine care for tunneled and non-tunneled. 40% of the units collected data on infection rates per catheter days. General opinion (39%) was identified as the reason to base CVDC protocols while descriptive studies (25%), RCTs (23%) and guidelines (18%) were also reported. Conclusion: There are significant variations in the Australian nursing practice related to the care of CVDCs. Although there is still practice based on general opinion there is evidence that changes in practice in the past 8 years may be associated with knowledge derived from research.

Automated detection of lung nodules in computed tomography images: a review

Lung nodules refer to a range of lung abnormalities the detection of which can facilitate early treatment for lung patients. Lung nodules can be detected by radiologists through examining lung images. Automated detection systems that locate nodules of various sizes within lung images can assist radiologists in their decision making. This paper presents a study of the existing methods on automated lung nodule detection. It introduces a generic structure for lung nodule detection that can be used to represent and describe the existing methods. The structure consists of a number of components including: acquisition, pre-processing, lung segmentation, nodule detection, and false positives reduction. The paper describes the algorithms used to realise each component in different systems. It also provides a comparison of the performance of the existing approaches.

Two-year results of a randomized placebo-controlled trial of vertebroplasty for acute osteoporotic vertebral fractures

We previously reported the results of a randomized controlled trial that found no benefit of vertebroplasty over a sham procedure for acute osteoporotic vertebral fractures up to 6 months. We report here the 12-month and 24-month clinical outcomes of this trial. Eligible participants (n = 78) were randomly assigned to receive either vertebroplasty (n = 38) or a sham procedure (n = 40). Randomization was stratified by treatment center, sex, and symptom duration (<6 weeks or ≥6 weeks). Participants, investigators (except the treating radiologists), and outcome assessors were blinded to group assignments. Enrolment occurred between April 2004 and October 2008 with follow-up completed October 2010. The primary outcome was overall pain measured on a scale of 0 (no pain) to 10 (maximal imaginable pain). Secondary outcomes included pain at rest and at night, disability, quality of life, perceived recovery, and adverse events, including incident clinically apparent vertebral fractures. At 12 and 24 months, complete data were available for 67 (86%) and 57 (73%) participants, respectively. At 12 months participants in the active group improved by 2.4 ± 2.7 (mean ± SD) units in overall pain compared with 1.9 ± 2.8 units in the sham group, adjusted between-group mean difference (MD) 0.3 (95% confidence interval [CI], –0.9 to 1.5), whereas at 24 months participants in the active group had improved by 3.0 ± 3.1 units compared with 1.9 ± 3.0 units in the sham group, MD 1.1 (95% CI, –0.3 to 2.4). No significant between-group differences were observed for any of the secondary efficacy outcomes at 12 or 24 months. There were no between-group differences in incident clinical vertebral fractures up to 24 months (active: n = 14, sham: n = 13), although the study had inadequate power for this outcome. These results provide further evidence that the use of this treatment in routine care is unsupported.

New vertebral fractures after vertebroplasty: 2-year results from a randomised controlled trial

Summary: A randomised controlled trial of vertebroplasty (VP) versus placebo assessed the effect of VP on the risk of further vertebral fractures. While no statistically significant between-group differences for new or progressed fracture risk at 12 and 24 months were observed, we observed a consistent trend towards higher risk of any type of fracture in the group undergoing VP. Our analysis was underpowered, and further adequately powered studies are needed to be able to draw firm conclusions about further vertebral risk with vertebroplasty. Purpose: This study seeks to assess the effect of VP on the risk of further radiologically apparent vertebral fracture within two years of the procedure. Methods: We conducted a randomised placebo-controlled trial of VP in people with acute osteoporotic vertebral fracture. Eligible participants were randomly assigned to VP (n = 38) or placebo (n = 40). Cement volume and leakage were recorded for the VP group. Plain thoracolumbar radiographs were taken at baseline, 12 and 24 months. Two independent radiologists assessed these for new and progressed fractures at the same, adjacent and non-adjacent levels. Results: At 12 and 24 months, radiographs were available for 45 (58 %) and 47 (60 %) participants, respectively. There were no between-group differences for new or progressed fractures: 32 and 40 in the VP group after 12 and 24 months compared with 21 and 33 in the placebo group (hazard ratio (HR) 1.80, 95 % confidence interval (CI) 0.82 to 3.94). Similar results were seen when considering only adjacent (HR (95 % CI) 2.30 (0.57 to 9.29)) and non-adjacent (HR (95 % CI) 1.45 (0.55 to 3.81) levels. In all comparisons, there was a consistent trend towards higher risk of any type of fracture in the group undergoing VP. Within the VP group, fracture risk was unrelated to total (HR (95 % CI) 0.91 (0.71 to 1.17)) or relative (HR (95 % CI) 1.31 (0.15 to 11.48)) cement volume or cement leakage (HR (95 % CI) 1.20 (0.63 to 2.31)). Conclusion: For patients undergoing VP, our study did not demonstrate significant increases in subsequent fracture risk beyond that experienced by those with vertebral fractures who did not undergo the procedure. However, because of the non-significant numerical increases observed, studies with adequate power are needed to draw definite conclusions about fracture risk.

Application of wavelets to the evaluation of phantom images for mammography quality control

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Evaluation of simulated external root resorptions with digital radiography and digital subtraction radiography

Introduction: Root resorption can cause damage in orthodontic patients. Digital subtraction radiography (DSR) is a useful resource for the detection of mineral losses. The purpose of this study was to compare the efficacy of digital radiography (DR) and DSR in detecting simulated external root resorption. Examiner agreement between the 2 techniques was also evaluated. Methods: Root resorptions of various sizes were simulated on the apical and lingual aspects of 49 teeth from 9 dry human mandibles. The teeth were radiographed in standardized conditions. The radiographs were registered with Regeemy Image Registration and Mosaicking (version 0.2.43-RCB, DPI-INPE, Sao Jose dos Campos, São Paulo, Brazil) and subtracted with Image Tool (University of Texas Health Science Center at San Antonio). The subtracted images and the digital radiographs were evaluated by 3 oral radiologists. Results: No statistically significant differences were found for the methods in the detection of apical root resorptions, independently from lesion size, and of lingual resorptions of 1.2 mm or greater. DSR was significantly better than DR for detection of lingual resorptions up to 1 mm. Resorptions less than 0.5 mm were not precisely detected by either method. DSR provided better intraexaminer and interexaminer agreement than did DR. Conclusions: Both methods are precise for detection of apical root resorptions as small as 0.5 mm and lingual resorptions of 1 mm or more. However, DSR frequently performed better than did DR. (Am J Orthod Dentofacial Orthop 2011;139:324-33)

Clinical and MRI investigation of temporomandibular joint in major depressed patients

Objective: The aim of the present study was to describe the clinical and MRI findings of the temporomandibular joint (TMJ) in patients with major depressive disorders (MDDs) of the non-psychotic type.Methods: 40 patients (80 TMJs) who were diagnosed as having MDDs were selected for this study. The clinical examination of the TMJs was conducted according to the research diagnostic criteria and temporomandibular disorders (TMDs). The MRIs were obtained bilaterally in each patient with axial, parasagittal and paracoronal sections within a real-time dynamic sequence. Two trained oral radiologists assessed all images. For statistical analyses, Fisher's exact test and chi(2) test were applied (alpha = 0.05).Results: Migraine was reported in 52.5% of subjects. Considering disc position, statistically significant differences between opening patterns with and without alteration (p = 0.00) and between present and absent joint noises (p = 0.00) were found. Regarding muscular pain, patients with and without abnormalities in disc function and patients with and without abnormalities in disc position were not statistically significant (p = 0.42 and p = 0.40, respectively). Significant differences between mandibular pathway with and without abnormalities (p=0.00) and between present and absent joint noises (p=0.00) were observed.Conclusion: Based on the preliminary results observed by clinical and MRI examination of the TMJ, no direct relationship could be determined between MDDs and TMDs. Dentomaxillofacial Radiology (2012) 41, 316-322. doi: 10.1259/dmfr/27328352

Comparação dos tempos de geração e digitação de laudos radiológicos entre um sistema eletrônico baseado em voz sobre IP (VoIP) e um sistema tradicional baseado em papel

OBJETIVO: Comparar os tempos de geração e digitação de laudos radiológicos entre um sistema eletrônico baseado na tecnologia de voz sobre o protocolo de internet (VoIP) e o sistema tradicional, em que o radiologista escreve o laudo à mão. MATERIAIS E MÉTODOS: Foi necessário modelar, construir e implantar o sistema eletrônico proposto, capaz de gravar o laudo em formato de áudio digital, e compará-lo com o tradicional já existente. Por meio de formulários, radiologistas e digitadores anotaram os tempos de geração e digitação dos laudos nos dois sistemas. RESULTADOS: Comparadas as médias dos tempos entre os sistemas, o eletrônico apresentou redução de 20% (p = 0,0410) do tempo médio de geração do laudo em comparação com o sistema tradicional. O tradicional foi mais eficiente em relação ao tempo de digitação, uma vez que a média de tempo do eletrônico foi três vezes maior (p < 0,0001). CONCLUSÃO: Os resultados mostraram diferença estatisticamente significante entre os sistemas comparados, sendo que o eletrônico foi mais eficiente do que o tradicional em relação ao tempo de geração dos laudos, porém, em relação ao tempo de digitação, o tradicional apresentou melhores resultados.

Influence of image filters on the reproducibility of measurements of alveolar bone loss

The reproducibility of measurements of alveolar bone loss on radiographs may be a problem on epidemiologic studies, as they are based on comparisons of the diagnosis of various examiners. The aim of the present research paper was to assess the inter- and intra-examiner reproducibility of measurements of the interproximal alveolar bone loss on non-manipulated digital radiographs and after the application of image filters. Five Oral Radiologists measured the distance between the cementoenamel junction (CEJ) to the alveolar crest or to the deepest point of the bony defect on 12 interproximal digital radiographs of molars and bicuspids of a dry human skull. The digital manipulation and the linear measurements were obtained with the Trophy Windows software (Throphy®). For each image, six different versions were created: 1) non-manipulated; 2) bright-contrast adjustment; 3) negative; 4) negative with brightness-contrast adjustment; 5) pseudo-colored; 6) pseudo-colored with brightness-contrast adjustment. In order to prevent interpretation bias because of the repetition of measurements, the examiners measured the radiographs in a random sequence. The two-way ANOVA test at 5% level of significance to compare the means of readings of the same operator with each filter indicated p<0.05 for the majority of operators, while the comparison between the mean values of operators using the same filter indicated p>0.05 for all filters. Based on the results, we concluded that linear measurements of interproximal alveolar bone loss on digital radiographs are highly reproducible among examiners. Nevertheless, the application of image filters significantly influenced the degree of intra-examiner reproducibility. Some filters even reduced the reproducibility of intra-examiner readings.

Otimização de imagens de mamografia computadorizada

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)