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Digital Images (digital + image)
Terms modified by Digital Images Selected AbstractsAutomated Digital Image Based Measurement of Boundary Fractal Dimension for Complex NanoparticlesPARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 1 2003Ramitha Wettimuny Abstract There is a growing realization that complex nanoparticles produced by combustion reaction, precipitation, and spray technology using supercritical fluids, are fractally structured. The boundary fractal dimension is linked to the flow, packing and consolidation dynamics of nanopowders. It also contains information on the formation dynamics of the nanoparticles produced by various methods. Extraction of the fractal dimension information embodied in the nanoparticle's fractal structure is hampered by the lack of automated characterization algorithms for processing images of particles. This paper describes an efficient algorithm for analyzing digitized images of fractally structured nanoparticles and presents a computer program that automates the procedure using digital image processing techniques. The program functionality is demonstrated and discussed using digital images of typical pigment, ceramic and pharmaceutical powders. [source] A Simple Tool for Teaching Flap Design with Digital ImagesDERMATOLOGIC SURGERY, Issue 12 2001Daniel Berg MD Background. Defects created by excision or Mohs micrographic surgery must be analyzed and surgical options including flaps must be considered. Teaching flap design to dermatology trainees is often done at the bedside of the patient with the trainee describing or marking a proposed flap. Open discussion of the options in this way is sometimes unnerving for the patient. Blackboard discussions or drawings are limited in their realism. Objective. To describe a rapid, simple method using commonly available software to allow a trainee to draw and redraw a proposed flap on a digital image of the defect without the time and cost of printing. Methods. We describe a feature in the widely used presentation program Microsoft PowerPoint which can be used to draw on an imported digital image in various colors. Results. A digital photograph taken at the bedside can quickly be loaded into PowerPoint and viewed as a full-screen picture on a computer. Using an electronic pen, multiple lines can be drawn and erased on the picture, allowing surgical planning and teaching away from the bedside. Conclusion. Design and analysis of potential incision lines for a flap can be done quickly using a digital image and commonly available software, allowing a new option for teaching flap design. [source] Effectiveness of HERO 642 versus Hedström files for removing gutta-percha fillings in curved root canals: an ex vivo studyINTERNATIONAL ENDODONTIC JOURNAL, Issue 11 2009B. Ayd Abstract Aim, To compare the effectiveness of gutta-percha removal and the maintenance of canal anatomy when using the HERO 642 system or Hedström files (H-files) in mandibular molar teeth. Methodology, The root canals of 40 mandibular molar teeth were instrumented using H-files and filled with gutta-percha and sealer. After 1 year in storage, the roots were sectioned horizontally to provide apical, middle and coronal root thirds. Sections were photographed, and an individual muffle was produced for each tooth. Teeth were randomly divided into four groups (n = 10) and the gutta-percha removed using either the HERO 642 system or H-files, with or without solvent. Digital images of the root canals were then re-taken. Root thirds were inspected for lateral perforations, and the percentage of the residual canal filling was determined on postoperative images. Transportation and centring ratio were calculated using preoperative and postoperative images of the cross-sections of root thirds. Results, H-files groups were associated with less filling material than the HERO 642 system (H-files,HERO 642 P = 0.056, H-files,HERO 642+solvent P = 0.041, H-files + solvent,HERO 642 P = 0.018, H-files + solvent,HERO 642 + solvent P = 0.016). The percentage of residual filling material was similar in the apical thirds, and the contribution of solvent to canal debridement was not statistically significant (P > 0.05). Perforation occurred mesiobuccally in 48% of specimens in the apical sections of mesial roots. There were no significant differences for centring ratio, transportation and perforation rate between groups. Conclusions, H-files left less gutta-percha overall; however, there was no difference in the apical third. The effect of solvent was not remarkable. Both instrument systems created a large number of perforations. [source] Review of the UK NEQAS (H) digital morphology pilot scheme for continuing professional development accessed via the internetINTERNATIONAL JOURNAL OF LABORATORY HEMATOLOGY, Issue 5 2008M. L. BRERETON Summary UK NEQAS (H) developed and instigated a pilot scheme for digital morphology, which was accessed by participants over the internet in order to assess the viability of using high quality images as an educational tool for continuing professional development. The pilot scheme was trialled over a 2-year period with eight releases totalling 16 morphology cases. Digital images allowed participating individuals to examine and comment on exactly the same cells and compare their findings with those of other participants, consensus data from traditional glass slide surveys and expert opinion. Feedback from participants on their experience was then relayed back to the development team by UK NEQAS (H) in order to drive the educational format and to ensure that any new scheme would meet the requirements of the users. [source] Digital photography: A primer for pathologistsJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 2 2004Roger S. Riley Abstract The computer and the digital camera provide a unique means for improving hematology education, research, and patient service. High quality photographic images of gross specimens can be rapidly and conveniently acquired with a high-resolution digital camera, and specialized digital cameras have been developed for photomicroscopy. Digital cameras utilize charge-coupled devices (CCD) or Complementary Metal Oxide Semiconductor (CMOS) image sensors to measure light energy and additional circuitry to convert the measured information into a digital signal. Since digital cameras do not utilize photographic film, images are immediately available for incorporation into web sites or digital publications, printing, transfer to other individuals by email, or other applications. Several excellent digital still cameras are now available for less than $2,500 that capture high quality images comprised of more than 6 megapixels. These images are essentially indistinguishable from conventional film images when viewed on a quality color monitor or printed on a quality color or black and white printer at sizes up to 11×14 inches. Several recent dedicated digital photomicroscopy cameras provide an ultrahigh quality image output of more than 12 megapixels and have low noise circuit designs permitting the direct capture of darkfield and fluorescence images. There are many applications of digital images of pathologic specimens. Since pathology is a visual science, the inclusion of quality digital images into lectures, teaching handouts, and electronic documents is essential. A few institutions have gone beyond the basic application of digital images to developing large electronic hematology atlases, animated, audio-enhanced learning experiences, multidisciplinary Internet conferences, and other innovative applications. Digital images of single microscopic fields (single frame images) are the most widely utilized in hematology education at this time, but single images of many adjacent microscopic fields can be stitched together to prepare "zoomable" panoramas that encompass a large part of a microscope slide and closely simulate observation through a real microscope. With further advances in computer speed and Internet streaming technology, the virtual microscope could easily replace the real microscope in pathology education. Later in this decade, interactive immersive computer experiences may completely revolutionize hematology education and make the conventional lecture and laboratory format obsolete. Patient care is enhanced by the transmission of digital images to other individuals for consultation and education, and by the inclusion of these images in patient care documents. In research laboratories, digital cameras are widely used to document experimental results and to obtain experimental data. J. Clin. Lab. Anal. 18:91,128, 2004. © 2004 Wiley-Liss, Inc. [source] TOOTH WHITENING IN CHILDRENJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 6 2005K.J. Donly ABSTRACT Objective: This clinical study evaluated the efficacy and tolerability of tooth whitening in children and adolescents, using a marketed, tray- based tooth-whitening system and a disposable polyethylene strip system. Materials and Methods: A study population of 106 children and adolescents, ages 11 to 18 years, participated in this study. There were 61 girls and 45 boys, with a mean age of 14.7 years. Subjects were divided into two experimental treatment groups, the groups being balanced with respect to demographic characteristics and baseline tooth color. All subjects had to have all permanent anterior teeth erupted, a baseline Vita shade (Vita Zahnfabrik, Bad Säckingen, Germany) score of A2 or darker, and the desire to whiten their teeth. One experimental group included 71 subjects who used a 6.5% hydrogen peroxide strip system (Crest Whitestrips Professional Strength, Procter & Gamble, Mason, OH, USA) for 30 minutes twice daily. The other experimental group included 35 subjects who used a 10% carbamide peroxide tray system (Opalescence, Ultradent Products, South Jordan, UT, USA) overnight. Subjects who had previously vital bleached their teeth, exhibited apparent caries or periodontal problems, had orthodontic appliances or anterior restorations, or reported dentin hypersensitivity were excluded. The study population was treated in two separate cohorts, by two independent investigations, to minimize the effects of examiner bias. Digital images were collected for all subjects at baseline, 2 weeks, and 4 weeks, with the maxillary and mandibular arches being treated separately for 4-week intervals. An oral examination was conducted at baseline and at all recall intervals. Subjects reported any adverse events in interviews. Color change was calculated from digital images where L* indicated lightness, a* redness, and b* yellowness. Comparisons between the two experimental groups were made using a two-sided analysis of covariance with a 5% significance level. Results: Both experimental systems exhibited significant (p < .001) tooth-whitening improvement relative to the baseline. Color change was greater in the maxillary teeth than in the mandibular teeth for both systems evaluated. The color change for maxillary teeth was not significantly different between the two systems evaluated; however, the tray system demonstrated significantly (p < .05) greater toothwhitening effectiveness for the mandibular teeth. Both treatment regimens were well tolerated. Minor tooth sensitivity and oral irritation were the most commonly reported adverse events, being reported by 49% of the subjects assigned to the strip group and 43% of the subjects in the tray group. All reported that adverse events were relieved immediately upon discontinuance of product use. Conclusion: The 6.5% hydrogen peroxide gel strips and the 10% carbamide peroxide gel delivered overnight in customized trays effectively whitened teeth, and both treatment regimens were well tolerated. [source] CLINICAL TRIALS ON THE USE OF WHITENING STRIPS IN CHILDREN AND ADOLESCENTSJOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 6 2005K.J. Donly ABSTRACT Objective: This article reported the cumulative findings from three controlled, randomized clinical trials evaluating the efficacy and tolerability of tooth whitening in children and adolescents using disposable polyethylene strip systems. Materials and Methods: The study population included 132 children and adolescents, ages 10 to 18 years. (Please note that 71 of these subjects were identified in the previous review.) Fifty-three percent of the subjects were female and 47% were male, with a mean age of 14.4 years. Subjects were divided into experimental treatment groups by balancing groups with respect to demographic characteristics and baseline tooth colors. Subiects were treated with either 5.3% or 6.5% hydrogen peroxide gel polyethylene strips. All subjects had to have all permanent anterior teeth erupted, a baseline Vita shade (Vita Zahnfabrik, Bad Säckingen, Germany) score of A2 or darker, and a desire that their teeth be whitened. One study included subjects who had previously received comprehensive orthodontic treatment. Digital images were collected for all subjects at baseline, 2 weeks, and 4 weeks. Oral examinations and interviews were conducted at each appointment to evaluate adverse events. Color change was calculated from the digital images in the same manner previously described. Results: The 5.3% and 6.5% hydrogen peroxide strips used for 30 minutes twice a day yielded significant tooth whitening (p < .0001) after 14 days. For the primary whitening parameter, ,b*, continued treatment during the 14- to 28-day period resulted in significant additional reduction in yellowness (p < .0001). Subjects treated with 6.5% hydrogen peroxide strips experienced significantly (p < .03) greater reduction in yellowness (approximately 0.8 ,b* units) compared with those who used the 5.3 hydrogen peroxide strips. The hydrogen peroxide strips were tolerated well in all of these studies, with minor tooth sensitivity and oral irritation being the primary complaints. Eighteen subjects (14%) reported oral irritation, whereas 30 subjects (23%) reported tooth sensitivity. All adverse events were relieved upon discontinuance of product use. Conclusion: The 5.3% and 6.5% hydrogen peroxide gel strips used for 30 minutes twice a day effectively whitened teeth, and both regimens were well tolerated. [source] Effect of Light Intensity on Color Performance of False Clownfish, Amphiprion ocellaris CuvierJOURNAL OF THE WORLD AQUACULTURE SOCIETY, Issue 3 2009Inayah Yasir Color performance of false clownfish, Amphiprion ocellaris Cuvier, was examined under three levels of light intensity (20,50 , 600,850 , and 2700,3500 lx) for 5 wk. The experiment was conducted in nine rectangular glass aquaria (25 × 25 × 20 cm) with three replicates. Each aquarium was stocked with 36 fish, and 3 fish were randomly sampled from each aquarium every other week. Digital images were taken weekly on each individual fish after it was anesthetized in MS-222. The color performance in hue, saturation, and brightness was quantified using image analysis. In addition to the whole-body analysis, each fish image was divided into ventral and dorsal parts to assess the body position-dependent effect. Furthermore, color differences between dorsal fin, anal fin, ventral fin, and caudal fin were also quantified. The whole body was brighter at low light than at medium or at high light intensity. Irrespective of light intensity, the dorsal side was more orange but less bright than the ventral side. Brighter light strengthened overall orange color on fish fins. The dorsal fin and ventral fins appeared more orange than the anal and caudal fins regardless of light intensity and exposure duration. Similar to body color, low light also led to brighter fins, especially for caudal and dorsal fins. Our results indicate that ambient light could regulate fish color performance but could not change the pigment dominance by ,-carotene. Light intensity is unlikely to change the contrast between dorsal and ventral sides, but dim light tends to make fish body brighter, and bright light strengthens orange color on fins. [source] Computer-aided calibration for visual estimation of vegetation coverJOURNAL OF VEGETATION SCIENCE, Issue 6 2009Åsa Gallegos Torell Abstract Question: What precision and accuracy of visual cover estimations can be achieved after repeated calibration with images of vegetation in which the true cover is known, and what factors influence the results? Methods: Digital images were created, in which the true cover of vegetation was digitally calculated. Fifteen observers made repeated estimates with immediate feedback on the true cover. The effects on precision and accuracy through time were evaluated with repeated proficiency tests. In a field trial, cover estimates, before and after calibration, were compared with point frequency data. Results: Even a short time of calibration greatly improves precision and accuracy of the estimates, and can also reduce the influence of different backgrounds, aggregation patterns and experience. Experienced observers had a stronger tendency to underestimate the cover of narrow-leaved grasses before calibration. The field trial showed positive effects of computer-based calibration on precision, in that it led to considerably less between-observer variation for one of the two species groups. Conclusions: Computer-aided calibration of vegetation cover estimation is simple, self-explanatory and time-efficient, and might possibly reduce biases and drifts in estimate levels over time. Such calibration can also reduce between-observer variation in field estimates, at least for some species. However, the effects of calibration on estimations in the field must be further evaluated, especially for multilayered vegetation. [source] Censusing and monitoring black rhino (Diceros bicornis) using an objective spoor (footprint) identification techniqueJOURNAL OF ZOOLOGY, Issue 1 2001Zoë C. Jewell Abstract An objective, non-invasive technique was developed for identifying individual black rhino from their footprints (spoor). Digital images were taken of left hind spoor from tracks (spoor pathways) of 15 known black rhino in Hwange National Park, Zimbabwe. Thirteen landmark points were manually placed on the spoor image and from them, using customized software, a total of 77 measurements (lengths and angles) were generated. These were subjected to discriminant and canonical analyses. Discriminant analysis of spoor measurements from all 15 known animals, employing the 30 measurements with the highest F -ratio values, gave very close agreement between assigned and predicted classification of spoor. For individual spoor, the accuracy of being assigned to the correct group varied from 87% to 95%. For individual tracks, the accuracy level was 88%. Canonical analyses were based on the centroid plot method, which does not require pre-assigned grouping of spoor or tracks. The first two canonical variables were used to generate a centroid plot with 95% confidence ellipses in the test space. The presence or absence of overlap between the ellipses of track pairs allowed the classification of the tracks. Using a new ,reference centroid value' technique, the level of accuracy was high (94%) when individual tracks were compared against whole sets (total number of spoor for each rhino) but low (35%) when tracks were compared against each other. Since tracks with fewer spoor were more likely to be misclassified, track sizes were then artificially increased by summing smaller tracks for the same rhino. The modified tracks in a pairwise comparison gave an accuracy of 93%. The advantages, limitations and practical applications of the spoor identification technique are discussed in relation to censusing and monitoring black rhino populations. [source] Evaluation of Digital Image Discretization Error in Droplet Shape Measurement Using SimulationPARTICLE & PARTICLE SYSTEMS CHARACTERIZATION, Issue 5-6 2009Sina Ghaemi Abstract Droplet shape measurement using image based techniques can be conducted using shape parameters which consist of a number of geometric features of a droplet image. The accuracy of calculating these shape parameters and their capability in revealing shape deviation is considerably affected by the discretization of the image with a camera CCD. In this paper, a simulation of digital images is conducted to investigate the error caused by image discretization. The effect of this error on calculating area, perimeter, and also a selected number of shape parameters are investigated. Digital images of circular and elliptical discs at different image/pixel size ratio and locations relative to the pixel grid have been generated to simulate the projected view. Results show that the shape parameters demonstrate different levels of sensitivity to the desirable factor of shape deviation and the undesirable factor of image discretization. A "clearance factor" has been suggested and used to rank the shape parameters based on their compensation between sensitivity to shape deviation and image discretization. [source] Brief communication: Facial fluctuating asymmetry as a marker of sex differences of the response to phenotypic stressesAMERICAN JOURNAL OF PHYSICAL ANTHROPOLOGY, Issue 2 2010Özener Abstract Fluctuating asymmetry (FA) is thought to increase as a result of environmental perturbations during development. A number of studies involving measures of health and developmental stability other than FA have discussed the presumed increased buffering in females relative to males. But, there is little evidence in the literature on FA to support this hypothesis. This research was conducted to determine the level of difference in terms of facial FA between sexes under different environmental conditions. Group 1 included final year students from three high schools in Yenimahalle, a slum district of Ankara (males: N = 163, mean age = 17.55, sd = 0.50; females: N = 141, mean age = 17.48, sd = 0.38). Group 2 included students with higher socioeconomic background and was composed of final year students from three different private schools located in Cankaya (N = 171, mean age = 17.44, sd = 0.26; females: N = 152, mean age = 17.38, sd = 0.31). Digital images were used to assess the degree of facial asymmetry as measured from eight paired traits and calculated as a composite score. The study shows that the male students had higher facial asymmetry than the female students. However, the present difference reaches a significant level in the low-socioeconomic status group. As a result, it could be inferred that differences in developmental stability between sexes might emerge under stressful conditions. Am J Phys Anthropol 143:321,324, 2010. © 2010 Wiley-Liss, Inc. [source] Atypical Fetal Prostate Development is Associated with Ipsilateral Hypoplasia of the Wolffian Ducts in the ACI RatTHE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 5 2010Luke E. Hofkamp Abstract For over a half century, the ACI (August × Copenhagen) rat has been a primary model for studying renal agenesis and ipsilateral hypoplasia (IHP) of the Wolffian-derived structures (WDS). Because the ACI rat is also used as a model for prostate research, it is important to examine the relationship of IHP and urogenital sinus (UGS) development. The prostate is dependent on androgens for proper growth and differentiation. Alteration in androgen production and/or delivery to the UGS has the potential to perturbate normal development. In this study, we investigate whether the ipsilateral loss of the WDS is associated with altered prostate development. Digital images of serial-sectioned fetal ACI rat UGS were used to create three-dimensional (3-D) surface-rendered models of the developing prostate, seminal vesicle, vas deferens, and utricle on gestational day 21. The number and volume of prostate ducts developing from the UGS were calculated from the 3-D model data. Animals exhibiting IHP had a significant decrease in total fetal prostate volume (40%; P < 0.005) with significant regional specific differences when compared with normal male ACI rats. Anatomical and histological differences in the utricle, abnormal histology of the ipsilateral testes, and a truncation of the ipsilateral Wolffian ductal mesenchyme were also seen in the animals with IHP. Additional research is needed to further understand the mechanisms and consequences of IHP on prostate growth and development. Alterations to normal prenatal development of the male accessory sex organs can have important consequences for the growth and morphology of the adult gland. Anat Rec, 2010. © 2010 Wiley-Liss, Inc. [source] Quantification of Angiogenesis in Otosclerosis,THE LARYNGOSCOPE, Issue 5 2005Robert W. Jyung MD Abstract Objectives/Hypothesis: The determinants of clinical versus histologic otosclerosis are unknown, but angiogenesis is associated with active disease. We hypothesized that quantification of angiogenesis in otosclerotic human temporal bones could reveal significant differences between clinical and histologic cases. Study Design: We reviewed all otosclerosis specimens meeting criteria from the temporal bone collection of the Massachusetts Eye and Ear Infirmary and 10 normal controls. Methods: Digital images were taken at predilection sites, followed by computer-assisted analysis. Canalicular area (CA), the aggregate of vascular spaces within bone, microvessel density (MVD), area, and depth were the main measures. Evidence of a direct connection between local vessels and the vasculature of the otosclerotic focus was also recorded for each specimen. Results: The average area (mm2) and depth (number of sections containing otosclerosis) of clinical lesions was significantly greater than histologic lesions. Total microvessel counts were significantly greater in clinical versus histologic lesions, and both clinical and histologic lesions contained significantly greater numbers of microvessels than the normal otic capsule. CA was also significantly higher in clinical lesions. MVD was slightly but not significantly higher in clinical lesions. Importantly, a direct connection between named vessels and the otosclerotic vasculature was significantly more frequent in clinical lesions. Conclusions: Computer-assisted quantification revealed significantly greater measures of angiogenesis in clinical versus histologic otosclerosis. Direct connection to adjacent vessels may support angiogenesis in this disease. Sustained angiogenesis may be an important determinant of clinical otosclerosis. [source] Aortic and ventricular dilation and myocardial reduction in gestation day 17 ICR mouse fetuses of diabetic mothersBIRTH DEFECTS RESEARCH, Issue 6 2007J. Claudio Gutierrez Abstract BACKGROUND: Maternal diabetes mellitus is associated with increased fetal teratogenesis, including cardiovascular defects. Information regarding cardiovascular changes in late-gestation fetal mice, related to maternal hyperglycemia, is not present in the literature. METHODS: Late-gestation fetal heart and great vessel morphology were analyzed in fetuses from control and diabetic mice. Female ICR mice were injected with streptozocin (200 mg/kg IP) prior to mating to induce diabetes (n = 8). Nonhyperglycemic females were used as controls (n = 8). At day 17 of gestation, females were euthanized and one fetus was arbitrarily selected per litter to analyze the heart and great vessels. Six additional fetuses from different litters, showing external malformations (spina bifida and/or exencephaly), were also evaluated from the diabetic group. Fetal thoraxes were processed using routine histopathologic techniques, and 7-,m transversal sections were stained with hematoxylin-eosin. Digital images of sections were made and analyzed using NIH Image J software to compare regional cardiac development. Student's t tests for means were performed to determine differences between groups (p < .05). RESULTS: Maternal hyperglycemia caused a dilation of late-gestation fetal ventricular chambers, a reduction of total ventricular myocardial area, and an increase in transversal ascending thoracic aortic area. Three of six fetuses that displayed external malformations showed an overt cardiac defect, beyond the ventricular and myocardial changes. CONCLUSIONS: Maternal hyperglycemia altered morphology of the late-gestation fetal mouse heart. Postnatal persistence or consequences of late-gestation heart chamber dilation and myocardial reduction are not yet known. Birth Defects Research (Part A) 2007. © 2007 Wiley-Liss, [source] Digital images in museums: Digital desires: What are museums up to?BULLETIN OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE & TECHNOLOGY (ELECTRONIC), Issue 4 2008Layna White Editor of Special Section First page of article [source] Digital images in museums: Doing the DAM: Digital asset management at the Metropolitan Museum of ArtBULLETIN OF THE AMERICAN SOCIETY FOR INFORMATION SCIENCE & TECHNOLOGY (ELECTRONIC), Issue 4 2008Shyam Oberoi First page of article [source] Improving the reproducibility of diagnosing micrometastases and isolated tumor cells,CANCER, Issue 2 2005Gábor Cserni M.D., Ph.D. Abstract BACKGROUND The latest edition of the tumor-lymph node-metastasis (TNM) classification of malignant tumors distinguishes between isolated tumor cells (pN0) and micrometastases (pN1mi). The reproducibility of these categories has not been assessed previously. METHODS Digital images from 50 cases with low-volume lymph node involvement from axillary sentinel lymph nodes were circulated twice for evaluation (Evaluation Rounds 1 and 2) among the members of the European Working Group for Breast Screening Pathology, and the members were asked to categorize lesions as micrometastasis, isolated tumor cells, or something else and to classify each case into a pathologic lymph node (pN) category of the pathologic TNM system. Methods for improving the low reproducibility of the categorizations were discussed between the two evaluation rounds. , Statistics were used for the assessment of interobserver variability. RESULTS The , value for the consistency of categorizing low-volume lymph node load into micrometastasis, isolated tumor cells, or neither of those changed from 0.39 to 0.49 between Evaluation Rounds 1 and 2, but it was slightly lower for the pN categories (0.35 and 0.44, respectively). Interpretation of the definitions of isolated tumor cells (especially with respect to their localization within the lymph node), lack of guidance on how to measure them if they were multiple, and lack of any definitions for multiple simultaneous foci of lymph node involvement were listed among the causes of discordant diagnoses. CONCLUSIONS The results of the current study indicated that the definitions available have minor contradictions and do not permit a reproducible distinction between micrometastases and isolated tumor cells. Refinement of these definitions, therefore, is required. One refinement that may improve reproducibility is suggested in this report. Cancer 2005. © 2004 American Cancer Society. [source] A Simple Tool for Teaching Flap Design with Digital ImagesDERMATOLOGIC SURGERY, Issue 12 2001Daniel Berg MD Background. Defects created by excision or Mohs micrographic surgery must be analyzed and surgical options including flaps must be considered. Teaching flap design to dermatology trainees is often done at the bedside of the patient with the trainee describing or marking a proposed flap. Open discussion of the options in this way is sometimes unnerving for the patient. Blackboard discussions or drawings are limited in their realism. Objective. To describe a rapid, simple method using commonly available software to allow a trainee to draw and redraw a proposed flap on a digital image of the defect without the time and cost of printing. Methods. We describe a feature in the widely used presentation program Microsoft PowerPoint which can be used to draw on an imported digital image in various colors. Results. A digital photograph taken at the bedside can quickly be loaded into PowerPoint and viewed as a full-screen picture on a computer. Using an electronic pen, multiple lines can be drawn and erased on the picture, allowing surgical planning and teaching away from the bedside. Conclusion. Design and analysis of potential incision lines for a flap can be done quickly using a digital image and commonly available software, allowing a new option for teaching flap design. [source] An in vitro comparison of three thermal gutta percha systemsINTERNATIONAL ENDODONTIC JOURNAL, Issue 4 2001M. P. Horrocks Aim,The aim of this study was to compare the ability of three contemporary obturation techniques to resist microleakage, using root canals prepared in extracted single rooted teeth by a standardized method. Methodology,The shaping technique involved the use of tapered nickel titanium rotary files to create a uniform 0.08-mm/mm taper. Six groups were compared, two representing control groups, a third group being obturated with a warm vertical condensation technique, a fourth group by an injection thermoplasticized system, a fifth group with a thermomechanical compaction method and a sixth group using cold lateral condensation. A zinc oxide/eugenol sealer was used as the sealant in all the obturation procedures. Forty-six extracted teeth were used in the study, three teeth in each control group and 10 teeth in each of the remaining four groups. Microleakage was compared using dye leakage with Indian ink. Penetration of the dye at the gutta percha/dentine interface was visualized after the root had been rendered transparent. Dye leakage was then measured from four aspects with the use of a stereomicroscope and export of a digital image to a software package, to facilitate accurate assessment of dye penetration. Two parameters were measured for each sample, the mean dye penetration and maximum dye penetration. Results,The mean values for linear dye leakage in the thermomechanical compaction group was 0.53 mm, the warm vertical condensation group was 0.73 mm, the injection thermoplasticized group was 0.15 mm and the cold lateral condensation group was 0.53 mm. There was no statistical difference between the means of the different groups (P > 0.05). The mean of the maximum values for dye leakage in the thermomechanical compaction group was 0.65 mm, the warm vertical condensation group was 1.02 mm, the injection-thermoplasticized group was 0.28 mm and the cold lateral condensation group was 0.74 mm. There was no statistical difference between the means of the different groups (P > 0.05). Conclusions,Within the conditions of this study, there was no statistical difference between the different groups with respect to either mean or maximum dye leakage. [source] Interval type-2 fuzzy logic for edges detection in digital imagesINTERNATIONAL JOURNAL OF INTELLIGENT SYSTEMS, Issue 11 2009Olivia Mendoza Edges detection in a digital image is the first step in an image recognition system. In this paper, we show an efficient edges detector using an interval type-2 fuzzy inference system (FIS-2). The FIS-2 uses as input the original images after applying Sobel filters and attenuation filters, then the fuzzy rules infer normalized values for the edges images, especially useful to enhance the performance of neural networks. To illustrate the results, we built frequency histograms of some images and compare the results of the FIS-2 edge's detector with the gradient magnitude method and a type-1 fuzzy inference system (FIS-1). The FIS-2 results are better than the gradient magnitude and FIS-1, because the edges preserve more detail of the original images, and the backgrounds are more homogeneous than with FIS-1 and the gradient's magnitude method. © 2009 Wiley Periodicals, Inc. [source] Application of image-guided biopsy for impalpable breast lesions in Chinese womenANZ JOURNAL OF SURGERY, Issue 1-2 2003Flora H. F. Tsang Background: Screening for breast cancer has resulted in an increasing number of mammographically detected lesions that require further management. The Advanced Breast Biopsy Instrumentation system is a recently added biopsy technique for the management of such lesions. The present paper will review the authors' experience in the use of this procedure in Chinese patients whose breast volume was smaller than that of Caucasians. Methods: Ninety-three patients were listed for the procedure and 78 (84%) underwent the procedure successfully. Ninety-two lesions were biopsied. Advanced Breast Biopsy Instrumentation (ABBI) was performed for clustered microcalcifications or abnormal mass/density. Minimally Invasive Breast Biopsy (MIBB), a suction-assisted core biopsy device, was employed for more scattered lesions. For small volume breasts, it may be required to bring the hand through the aperture to get the targeted lesions onto the digital image or, in the case of ABBI, to excise just beyond the deep margin of the lesion rather than the recommended depth. Results: The ABBI was performed for 43 (46.7%) lesions and MIBB for 49 (53.3%) lesions. Nine (9.8%) were diagnosed to have ductal carcinoma in situ, two (2.2%) had ductal carcinoma in situ with microinvasion and eight (8.7%) had invasive ductal carcinoma. All the malignant lesions required further management. In addition, 19 (20.7%) were found to have atypical hyperplasia. Patients' satisfaction and cosmetic outcome are good. Conclusion: The ABBI and MIBB procedures can be applied satisfactorily for biopsy of mammographic lesions with good cosmetic outcome in Chinese patients. [source] An evaluation of the role of a store-and-forward teledermatology system in skin cancer diagnosis and managementCLINICAL & EXPERIMENTAL DERMATOLOGY, Issue 3 2005R. Mahendran Summary There is currently much interest in the potential role of telemedicine in improving the delivery of dermatological care in the UK. The two teledermatology systems available at present are divided into live video and store-and-forward technology. We investigated the value of a store-and-forward teledermatology system in the diagnosis and management of lesions suspicious of skin cancer. A total of 163 store-and-forward referrals of patients with one lesion each were assessed independently by a Consultant and a third-year trainee dermatologist. The accuracy of diagnosis and appropriateness of management from these assessments was compared to a subsequent face-to-face consultation with the Consultant. Analysis of the Consultants' diagnoses showed that 48% were identical for teledermatology and conventional face-to-face consultations. A further 17% of teledermatology diagnoses included the actual clinical diagnosis as a possibility but 20% were either incorrect or a diagnosis could not be made. In the remaining 15% of cases the digital image was of insufficient quality for assessment. Of the trainee's reports, 44% were identical to the clinical diagnoses and another 20% included the clinical diagnosis as a possibility. The management plan was appropriate in 55% of the total teledermatology referrals assessed by the Consultants and in 52% assessed by the trainee when compared with the conventional consultation. This study illustrates that the store-and forward type telemedicine system has limited diagnostic accuracy for skin lesions. However, our results suggest that store-and-forward teledermatology may be suitable and safe for screening out clearly benign lesions but the study casts doubt on its efficiency. [source] Marginal Bone Level around Implants Assessed in Digital and Film Radiographs: In Vivo Study in the DogCLINICAL IMPLANT DENTISTRY AND RELATED RESEARCH, Issue 1 2000Eva Borg DDS ABSTRACT Background: One of the objectives of postoperative radiographic examinations of implants is to evaluate the marginal bone height and its changes over time. Purpose: The purpose of this study was to assess the influence of digital image processing on measurements of the marginal bone level around implants. Material and Methods: Implants in beagle dogs, used to study the development of peri-implantitis and subsequent healing following treatment, were monitored with conventional radiography and a digital image plate system. Five observers measured the distance between a reference point and the bone level. Measurements in conventional radiographs were made with the use of an x-ray viewer (2X) and a magnifying lens (7X). For the digital images, the system's built-in measuring function was used together with five image processing techniques: edge enhancement (matrixes set on 5 and 25), inverted grey scale, single color highlight, and color intensity mapping together with the brightness and contrast control. From the time of maximum breakdown and the end of the experiment, histologic values were available. Results: Differences between techniques and observers increased toward the end of the healing period. Measurements made at maximum breakdown did not differ significantly from the histologic value. Measurements made after healing all methods, except that using edge enhancement and a 25 × 25 kernel, differed significantly from the histologic value by underestimating the bone level. Conclusions: Measurements of bone level around implants from digital radiographs are as accurate and precise as those from film images. In particular cases, the use of specific image processing algorithms may improve both accuracy and precision. After healing, the histologic specimens showed an incomplete bone fill in the crater with a remaining thin layer of connective tissue in contact with the fixture, and in such situations, the morphology of the bone will give a more complicated diagnostic task. [source] 3D Image Segmentation of Aggregates from Laser ProfilingCOMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING, Issue 4 2003Hyoungkwan Kim Automated scanners of different designs use cameras or lasers to obtain digital images of groups of aggregate particles. To accurately determine particle size and shape parameters, each particle region in the image must be isolated and processed individually. Here, a method for segmenting a particle image acquired from laser profiling is developed using a Canny edge detector and a watershed transformation. Canny edges with rigorous and liberal threshold values are used to outline particle boundaries on a binary image and to check the validity of watersheds, respectively. To find appropriate regional minima in the watershed transformation, a varying search window method is used, where the number of neighboring pixels being compared with the pixel of interest is determined from the height value of the pixel. Test results with this method are promising. When implemented in automated systems that are designed to rapidly assess size and shape characteristics of stone particles, this technique can not only reduce the amount of time required for aggregate preparation, but also increase the accuracy of analysis results. [source] Heart changes in 17-day-old fetuses of diabetic ICR (Institute of Cancer Research) mothers: Improvement with maternal immune stimulationCONGENITAL ANOMALIES, Issue 1 2009Juan Claudio Gutierrez ABSTRACT Maternal diabetes mellitus is associated with increased fetal teratogenesis, including cardiovascular defects. Non-specific maternal immune stimulation with Freund's complete adjuvant (FCA) or interferon gamma (IFN,) has been associated with protection against birth malformations. Using a diabetic mouse model, late-gestation fetal heart and great vessel morphology were analyzed. Four groups of mice were used: non-diabetic females as a control group, hyperglycemic females induced by streptozotocin as a diabetic group, and diabetic females injected either with FCA or IFN,. At day 17 of gestation, females were euthanized and one fetus was arbitrarily selected per litter for fixation and sectioning. Treatment-induced changes in cardiac development were assessed from digital images of serial sections taken at standardized levels in the thorax. One-way parametric and non-parametric ANOVA and ordinal logistic regression were performed to compare the difference among groups (P < 0.05). Maternal hyperglycemia altered morphology of the late-gestation fetal mouse heart by causing ventricular chamber dilation, sectional myocardial reduction, and an increase in transversal aortic area. FCA protected the fetal heart from cavitary dilation in diabetic mothers. FCA and IFN, protected the fetal heart against reduction of myocardial area, and ascending thoracic aorta dilation. Consequences of late gestation heart chamber dilation and myocardial reduction are not yet known. Maternal immune stimulation partially protected against these developmental defects by mechanisms that remain unclear. [source] Acquired Melanocytic Lesions and the Decision to Excise: Role of Color Variegation and Distribution as Assessed by DermoscopyDERMATOLOGIC SURGERY, Issue 2 2005Stefania Seidenari MD Background Because melanoma may sometimes be difficult to differentiate from nevi with clinical atypia, many benign lesions also undergo surgical removal. Objective To assess color type and distribution in dermoscopic melanocytic lesion images and to analyze the influence of color parameters on the diagnostic process and the decision to excise. Methods Overall, 603 images, referring to 112 melanomas and 491 nevi, were retrospectively subdivided into four groups: "clearly benign,""follow-up,""dermoscopic atypical nevi," and "dermoscopic melanomas," according to their dermoscopic aspects. The frequency of color type, number, and asymmetry were evaluated on digital images. Results With respect to lesions not eligible for excision according to dermoscopy (but excised for cosmetic reasons), those excised with a suspicion of malignancy showed a higher number of colors, whose distribution was also more asymmetric. Moreover, the frequency of the presence of black and blue-gray progressively increased from clearly benign lesions to atypical nevi and dermoscopic melanomas. Conclusion In dermoscopic images, color parameters are essential elements for the diagnosis of atypical nevus, which can be differentiated from both a clearly benign lesion and a melanoma. Furthermore, pigmentation asymmetry and the presence of blue-gray represent the main color features, which should lead to the decision to excise. THIS STUDY WAS PARTIALLY SUPPORTED BY A GRANT FROM MINISTERO ISTRUZIONE UNIVERSITÇ E RICERCA. [source] Telepathology as an Aid in Mohs Micrographic SurgeryDERMATOLOGIC SURGERY, Issue 6 2004Suresh Chandra MB Background. Mohs surgeons are occasionally confronted by challenging pathology ideally requiring the advice of a dermatopathologist. The Internet transmission of digital images of the pathology (telepathology) allows for such opinions to be easily and rapidly obtained. Objective. The objective was to obtain images utilizing a digital camera focused directly through one microscope eyepiece with subsequent e-mail to a pathologist for an immediate opinion. Methods. The particular area of interest on the slide is selected. The lens of the digital camera is placed directly on one eyepiece of the microscope and using the zoom and autofocus options of the camera a sharp image is obtained. The camera flash must be disabled. The images are immediately downloaded to computer and e-mailed to the pathologist for an opinion. Results. Three case reports illustrate that the pathologist is able to offer suggestions on a diagnosis with a high degree of confidence using the e-mailed images. Conclusion. Digital camera technology now allows for images to be taken directly through an eyepiece of the microscope. These images can be almost instantaneously e-mailed to a pathologist anywhere in the world for an immediate opinion. The technique provides for greater surety where doubt exists about the pathology during Mohs surgery. [source] A comparative evaluation of digital imaging, retinal photography and optometrist examination in screening for diabetic retinopathyDIABETIC MEDICINE, Issue 7 2003J. A. Olson Abstract Aims To compare the respective performances of digital retinal imaging, fundus photography and slit-lamp biomicroscopy performed by trained optometrists, in screening for diabetic retinopathy. To assess the potential contribution of automated digital image analysis to a screening programme. Methods A group of 586 patients recruited from a diabetic clinic underwent three or four mydriatic screening methods for retinal examination. The respective performances of digital imaging (n = 586; graded manually), colour slides (n = 586; graded manually), and slit-lamp examination by specially trained optometrists (n = 485), were evaluated against a reference standard of slit-lamp biomicroscopy by ophthalmologists with a special interest in medical retina. The performance of automated grading of the digital images by computer was also assessed. Results Slit-lamp examination by optometrists for referable diabetic retinopathy achieved a sensitivity of 73% (52,88) and a specificity of 90% (87,93). Using two-field imaging, manual grading of red-free digital images achieved a sensitivity of 93% (82,98) and a specificity of 87% (84,90), and for colour slides, a sensitivity of 96% (87,100) and a specificity of 89% (86,91). Almost identical results were achieved for both methods with single macular field imaging. Digital imaging had a lower technical failure rate (4.4% of patients) than colour slide photography (11.9%). Applying an automated grading protocol to the digital images detected any retinopathy, with a sensitivity of 83% (77,89) and a specificity of 71% (66,75) and diabetic macular oedema with a sensitivity of 76% (53,92) and a specificity of 85% (82,88). Conclusions Both manual grading methods produced similar results whether using a one- or two-field protocol. Technical failures rates, and hence need for recall, were lower with digital imaging. One-field grading of fundus photographs appeared to be as effective as two-field. The optometrists achieved the lowest sensitivities but reported no technical failures. Automated grading of retinal images can improve efficiency of resource utilization in diabetic retinopathy screening. Diabet. Med. 20, 528,534 (2003) [source] Testing automated liquid-based cytology samples with a manual liquid-based cytology method using residual cell suspensions from 500 ThinPrep casesDIAGNOSTIC CYTOPATHOLOGY, Issue 6 2006John A. Maksem M.D. Abstract We report a technical improvement upon a previously disclosed manual liquid-based cytology (MLBC) method; and, we use the improved method to prepare slides from residual ThinPrep specimens in order to see how often ThinPrep diagnoses correspond to diagnoses derived from exhaustive examination of their parent sample suspensions. Residual cell suspensions from 500 ThinPrep cases comprising (1) 20 low-grade squamous intraepithelial lesions (LSILs); (2) 200 high risk (HR) negatives and 20 ASC-US; and (3) 260 screening cytology specimens were studied. Institutional review committee guidelines allowed us to know diagnoses by groups of specimens, but did not allow us to know individual patient diagnoses, so we could not perform case-by-case matched outcome-comparisons. Cells were concentrated by conventional centrifugation and sedimented into a polymer gel that was then vortex-mixed and converted into a viscous cell-rich suspension. The cell suspension was smeared between two clean glass slides, which were air-dried and stained with the Papanicolaou stain. Two study-sets were created, comprising one slide from each case. Each of the two study sets was examined by two cytopathologists, and discordant diagnoses were adjudicated. Because of the ambiguity involved in the "atypical" (ASC-US, ASC-H, AGC) diagnosis categories, only outcomes at the level of LSIL or greater were recorded. All MLBC SILs were digitally imaged and abnormal slides plus digital images were sent to the laboratory that provided the residual automated liquid-based cytology (ALBC) suspensions. The final diagnoses were confirmed by the laboratory that provided the residual ALBC specimens. MLBC slides of the 20 LSIL cases afforded 2 high-grade squamous intraepithelial lesions (HSILs) and 18 LSILs. Those of the 200 HR-Negatives showed 3 HSILs and 30 LSILs; and those of the 20 HR-ASC-US showed 3 HSILs and 9 LSILs. MLBC slides of the 260 screening cytology specimens showed 1 Carcinoma, 3 HSILs and 20 LSILs; affording 3 HSILs and 14 LSILs more than originally diagnosed. The MLBC method of this report is useful for preparing cell suspensions for cytological examination. Our analytical method was exhaustive and used nearly all of the cell material that was provided to us for analysis; therefore, we conclude that this approach is useful for determining how well ALBC instruments represent their parent sample suspensions. It appears that "rare events" may be overlooked when limited sample aliquots are analyzed by ALBC instruments, and this probably accounts for our increased discovery of SILs by the MLBC method. Also, SILs often present as aggregates of cohesive cells which, if overlooked or ineffectively transferred to ALBC slides, would not be diagnosed. Diagn. Cytopathol. 2006;34:391,396. © 2006 Wiley-Liss, Inc. [source] | |||||||||||||||||||||||||||||||||||||||||||