Conversion of teaching file cases from film to digital format: a comparison between use of a diagnostic-quality digitizer and use of a flatbed scanner with transparency adapter

Preserving the value of legacy film-based teaching files in pediatric radiology

Senior pediatric radiologists who have spent a major portion of their careers interpreting conventional film-screen radiographic studies have collected a wealth of hard-copy teaching material that is at risk of becoming obsolete. The teaching value and usefulness of analog film teaching files can be preserved using available hardware and standard software. The final product can be made available in a high-quality digital format to students, trainees and faculty without complicated search-and-retrieval methodology. This paper describes a relatively simple and low-cost procedure to preserve and use this source of wisdom and experience. It also emphasizes the role that such a resource can play as part of a comprehensive educational program.

Chest radiograph findings in children aged 2-59 months hospitalised with community-acquired pneumonia, prior to the introduction of pneumococcal conjugate vaccine in India: a prospective multisite observational study

OBJECTIVES

The current study was a hospital-based surveillance of cases hospitalised with WHO-defined community-acquired pneumonia in children aged 2-59 months, to assess the radiological abnormalities in chest X-rays and to identify the demographic and clinical correlates of specific radiological abnormalities, in residents of prespecified districts of Uttar Pradesh and Bihar, India.

DESIGN

Prospective, active, hospital-based surveillance.

SETTING

Multisite study conducted in a network of 117 secondary/tertiary care hospitals in four districts of Uttar Pradesh and Bihar, India.

PARTICIPANTS

Included were children aged 2-59 months, hospitalised with community-acquired pneumonia, residing in the project district, with duration of illness <14 days and who had not been hospitalised elsewhere for this episode nor had been recruited previously.

MAIN OUTCOME MEASURE

Concordant radiological abnormalities in the chest X-rays.

RESULTS

From January 2015 to April 2017, 3214 cases were recruited and in 99.40% (3195/3214) chest X-rays were available, among which 88.54% (2829/3195) were interpretable. Relevant radiological abnormalities were found in 34.53% (977/2829, 95% CI 32.78 to 36.28). These were primary end point pneumonia alone or with other infiltrates in 22.44% (635/2829, 95% CI 20.90% to 23.98%) and other infiltrates in 12.09% (342/2829; 95% CI 10.88% to 13.29%). There was a statistically significant interdistrict variation in radiological abnormalities. Statistically significantly higher proportion of abnormal chest X-rays were found in girls, those with weight-for-age z-score ≤-3SD, longer duration of fever, pallor and with exposure to biomass fuel.

CONCLUSIONS

Among hospitalised cases of community-acquired pneumonia, almost one-third children had abnormal chest radiographs, which were higher in females, malnourished children and those with longer illnesses; and an intra-district variation was observed.

Development of standard digital images for pneumoconiosis

We developed the standard digital images (SDIs) to be used in the classification and recognition of pneumoconiosis. From July 3, 2006 through August 31, 2007, 531 retired male workers exposed to inorganic dust were examined by digital (DR) and analog radiography (AR) on the same day, after being approved by our institutional review board and obtaining informed consent from all participants. All images were twice classified according to the International Labour Office (ILO) 2000 guidelines with reference to ILO standard analog radiographs (SARs) by four chest radiologists. After consensus reading on 349 digital images matched with the first selected analog images, 120 digital images were selected as the SDIs that considered the distribution of pneumoconiosis findings. Images with profusion category 0/1, 1, 2, and 3 were 12, 50, 40, and 15, respectively, and a large opacity were in 43 images (A = 20, B = 22, C = 1). Among pleural abnormality, costophrenic angle obliteration, pleural plaque and thickening were in 11 (9.2%), 31 (25.8%), and 9 (7.5%) images, respectively. Twenty-one of 29 symbols were present except cp, ef, ho, id, me, pa, ra, and rp. A set of 120 SDIs had more various pneumoconiosis findings than ILO SARs that were developed from adequate methods. It can be used as digital reference images for the recognition and classification of pneumoconiosis.

Digitalização de filmes radiográficos com costura de imagens

OBJETIVO: Propor um método reprodutível, de fácil utilização e de baixo custo para a digitalização de filmes radiográficos de todos os tamanhos padrões, concentrando nossos esforços em filmes radiográficos de tórax. MATERIAIS E MÉTODOS: O objetivo de baixo custo ditou o uso de um escâner A4 com adaptador de transparência, bem como um software de costura de imagens otimizado, que tira proveito da geometria do escâner e área de captura constante, bem como o conhecimento das dimensões dos filmes radiográficos padrões. RESULTADOS: O resultado final do método proposto é uma imagem de alta resolução com bom contraste e sem artefatos de costura perceptíveis. CONCLUSÃO: O método de digitalização proposto usando um escâner A4 possibilita reprodutibilidade, excelente qualidade de imagem e alto grau de certeza na identificação de lesões.

Comparison of digitized and conventional radiographic images for assessment of hip joint conformation in dogs

OBJECTIVE

To determine agreement between assessments of canine hip joint conformation provided by board-certified radiologists after evaluation of digitized and conventional radiographic images.

SAMPLE POPULATION

200 pelvic radiographs previously evaluated by radiologists using the Orthopedic Foundation for Animals standard grading system for canine hip joint conformation.

PROCEDURES

Each of 20 board-certified radiologists evaluated conventional and digitized pelvic radiographs from each of 200 dogs for hip joint conformation. A weighted kappa coefficient and intraclass correlation were used to determine agreement between assessments derived from digitized radiographic images and conventional radiographs and between the original Orthopedic Foundation for Animals conformation ratings and assessments derived from each image format.

RESULTS

Overall, agreement between assessments derived from the digitized images and conventional radiographs was good, with all but 1 radiologist attaining a weighted kappa coefficient > 0.61. Intraclass correlation for each radiologist ranged from 0.75 to 0.98 (95% confidence interval, 0.67 to 0.984). On comparison of conformation assessments, 95.7% of those derived from conventional radiographs and digitized images were within 1 grade. On comparison of digitized radiographic conformation assessments and conformation ratings, 94.2% were within 1 grade. On comparison of conventional radiographic conformation assessments and conformation ratings, 92.3% were within 1 grade.

CONCLUSIONS AND CLINICAL RELEVANCE

The use of digitized radiographic images does not appear to impact the radiographic assessments of canine hip joint conformation made by consultant radiologists. Compared with conventional radiographs, the use of digitized radiographic images decreases storage space requirements and enables more rapid reporting of assessment results for individual dogs.

In vitro perception of low-contrast features in digital, film, and digitized dental radiographs: a receiver operating characteristic analysis

OBJECTIVE

To compare experimentally the image quality of charged-coupled device (CCD)-based digital, flatbed scanner digitized, and dental film radiographs.

STUDY DESIGN

High-contrast standardized radiographs of an aluminum step wedge containing boreholes were obtained on dental radiographic film (F) and a CCD receptor (D). Digitization (S) was done with a flatbed scanner. Each radiograph was separated into 23 single images, 18 of which showed a dark spot. Thirty observers indicated their confidence on the visibility of the spots for a receiver operating characteristic (ROC) analysis.

RESULTS

Mean Az values (area beneath the ROC curves) differed significantly (P < .05), being highest for D (Az = 0.76), followed by F (Az = 0.71) and S (Az = 0.60). Mean sensitivity of S (0.45) was significantly (P = .000) lower than for D (0.66) and F (0.67).

CONCLUSION

The difference between modality D and F was small. However, the inferior performance of S images, particularly in dark regions, could be clinically relevant.

Digital camera resolution and proximal caries detection

OBJECTIVES

To evaluate the diagnostic accuracy of proximal caries detection from digitized film images captured by a digital camera at different resolution settings.

METHODS

Twenty-five periapical radiographs of 50 premolar and 25 molar teeth were photographed using a digital camera, Sony Cyber-shot, DSC-S75 at three different resolution settings: 640 x 480, 1280 x 960 and 1600 x 1200. Seventy-five digital images were transferred to a computer, saved and opened using ACDSee software. In addition, a PowerPoint slide was made from each digital image. Five observers scored three groups of images (the films, the displayed 1:1 digital images on the ACDSee software, and the PowerPoint slides) for the existence of proximal caries using a 5-point confidence scale, and the depth of caries on a 4-point scale. Ground sections of the teeth were used as the gold standard. Az values under the receiver operating characteristic (ROC) curve of each group of images and at different resolutions were compared using the Friedman and Wilcoxon signed rank tests. Mean different values between the lesions' depth interpreted by the observers and that of the gold standard were analysed.

RESULTS

Films showed the highest Az values. Only the 1280 x 960 images on the ACDSee software showed no significant difference of the Az value from the films (P=0.28). The digital images from three resolution settings on the PowerPoint slides showed no significant differences, either among each other or between them and the films. For caries depth, the 1280 x 960 images showed lower values of mean difference in enamel lesions compared with the other two resolution groups.

CONCLUSIONS

This study showed that in order to digitize conventional films, it was not necessary to use the highest camera resolution setting to achieve high diagnostic accuracy for proximal caries detection. The 1280 x 960 resolution setting of the digital camera demonstrated comparable diagnostic accuracy with film and was adequate for digitizing radiographs for caries detection.

Digitizing and consolidating mammograms and other images for teaching applications

RATIONALE AND OBJECTIVES

Most mammograms are obtained using screen-film technique and must be digitized for teaching purposes. Digitizing mammograms poses special problems because of high contrast and multiple views. We describe the equipment and process for digitizing and consolidating mammograms for teaching purposes. These techniques can be applied to any type of images where consolidation may be helpful.

MATERIALS AND METHODS

Mammograms are digitized using a high optical density scanner. After the window and levels are adjusted, a four-view mammogram may be consolidated into a single image if desired.

RESULTS

The high contrast of film screen mammograms is managed by using a high optical density scanner. Consolidation of image sets, such as a four-view mammogram, allows images to be easily inserted into text, slide, or poster documents.

CONCLUSIONS

Digitizing mammograms for teaching purposes is facilitated by use of a high optical density scanner and consolidation of image sets into single images. The techniques described are also useful for other areas of radiology in which display of multiple images or modalities is desirable.

COMPARISON OF DIGITIZED AND DIRECT VIEWED (ANALOG) RADIOGRAPHIC IMAGES FOR DETECTION OF PULMONARY NODULES

The purpose of this study was to compare direct (analog) viewing of thoracic radiographs with digitized images obtained with a radiographic scanner and seven digital cameras for detection of pulmonary nodules. Direct viewing of the analog radiographs was significantly better than all digitized methods (P<0.01). Significant variations exist between the radiographic scanner and the digital cameras. The scanner (Kodak LS75) was significantly better than the Kodak DC 4800 and the Sony DSC-707 cameras (P<0.05). The Nikon 995, Canon EOS-D30, and Ricoh i500 were significantly better than the Sony DSC-707 (P<0.05). There was no significant difference between the Kodak DC 3800, Kodak DC 4800, and the Sony DSC-707. For pairwise comparison of raters (when evaluating the radiographs individually compared with the consensus), the raters matched the consensus rating from 85% to 92% with no significant difference between raters.

Reinventing the apprenticeship: the hot seat in the digital era

RATIONALE AND OBJECTIVES

Describe new interactive digital teaching methods for medical student education in radiology and evaluate student responses.

MATERIALS AND METHODS

Third- and fourth-year medical students on radiology clerkship were taught using either film-based "hot seat" format, digital "hot seat," or didactic slide-based format. Digital hot seat included direct projection of full-resolution images and use of digital tablet for annotation. Students completed surveys commenting on each method.

RESULTS

Before 2003-2004, comments were available from general course surveys. Only positive responses were made regarding digital hot seat format. Dedicated surveys of teaching methods since July 2003 (23 students) showed 100% gave high ratings to digital hot seat methods (1 or 2 on a scale from 1 to 5), citing easier visibility of findings and ability to draw on images as positive features. Fifty-two percent rated film hot seat method <3, with limited visibility as the main complaint. Didactic slide teaching was rated <3 by 74%. Eighty-three percent chose digital hot seat as their favorite format overall.

CONCLUSIONS

Students overwhelmingly favor digital hot seat teaching over film-based or didactic slide presentations. Digital hot seat methods preserve the best features of case-based interactive teaching while improving visibility of findings.