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Stefania Seidenari

Publications and source records attributed to Stefania Seidenari.

35 records · Page 2Linked to original sources
PubMed2004

Is JPEG compression of videomicroscopic images compatible with telediagnosis? Comparison between diagnostic performance and pattern recognition on uncompressed TIFF images and JPEG compressed ones.

Early melanoma diagnosis is an important goal for dermatologists. Polarized light systems are increasingly employed for dermatoscopic diagnosis of melanocytic lesions. For the purpose of teledermoscopy, whose importance is increasingly growing for consultation and teaching purposes, it is of utmost importance to establish whether, after compression, polarized light images maintain their informativeness. The aim of our study was to check the effects of compression on melanocytic lesion images acquired by means of a digital videomicroscope on the identification of morphological details of the image and on diagnostic accuracy. A total of 170 50-fold-magnified pigmented skin lesion images, acquired in Tagged Image File Format (TIFF) by a digital videomicroscope, were compressed using Joint Photographic Experts Group (JPEG) algorithms (compression factor 30). Two experts in videomicroscopy evaluated both original and compressed images twice by describing single lesion features and expressing a diagnosis. Reproducibility in the assessment of dermoscopic parameters and observer performance were studied by kappa statistics and Receiver Operating Characteristic (ROC) analysis. Both intra- and interobserver reproducibility in the assessment of morphological details were higher when TIFF images were considered, indicating a better image quality. Nonetheless, there was no significant difference in the diagnostic accuracy between uncompressed images and compressed ones, although the intraobserver reproducibility in the diagnostic judgement was higher for uncompressed images. Despite loss in image details, factor 30 compressed videomicroscopic images enable a good diagnostic accuracy.

Algorithms↗
PubMed2004

Automated description of colours in polarized-light surface microscopy images of melanocytic lesions.

The aim of this study was to develop a computerized method for the identification and description of colour areas in melanocytic lesion images based on an approach mimicking the human perception of colours. A colour palette comprising six colour groups (black, dark brown, light brown, blue-grey, red and white) was created by selecting single colour components within melanocytic lesion images acquired using a digital videomicroscope, and was implemented in the image analysis program. For each colour region, the area, the distance from the lesion centroid, the spread, the colour area distribution in the internal and the external part of the lesion, and asymmetries were assessed on 604 melanocytic lesion images in our image database. Black, white and blue-grey colour areas were detected more frequently in melanomas compared with naevi. Moreover, significant differences in colour descriptors were observed for each colour group, showing that colour areas are more unevenly distributed in melanomas compared with naevi. Using a discriminant analysis approach, the extension of dark, white and blue-grey areas and some descriptors of the distribution of the colour areas were identified as the most relevant colour parameters for differentiating between benign and malignant lesions. In conclusion, our automatic procedure breaks down the image into the colour areas used in the clinical examination process, and also supplies a description of their extension and distribution, with parameters that correlate with the clinical concepts of regularity and homogeneity.

Automation↗
PubMed2004

Reproducibility of atopy patch tests with Dermatophagoides: a study on 85 patients with atopic dermatitis.

Atopy patch tests (APTs) are considered a useful addition to standard testing procedures for the identification of allergens triggering the appearance of eczema in patients with atopic dermatitis (AD). The aim of the study was to evaluate the reproducibility of APTs with house dust mites by simultaneously patch testing AD patients. 85 subjects affected by AD, 36 males and 48 females, aged from 1 to 52 years, were patch tested with Dermatophagoides mix (D. pteron/D. farinae) 20% pet. In our patients, the percentage of agreement between the frequency of positive and negative responses to Dermatophagoides mix was 96.7%. Reproducibility was highly satisfactory, as evaluated by k-value (0.953). As regards the agreement in the intensity of APT responses to Dermatophagoides mix between the right and left sides, we found that reproducibility was also highly satisfactory (k = 0.851). In conclusion, for Dermatophagoides APTs, the agreement rate was similar to that of standard patch tests, and therefore APTs may be considered sufficiently reproducible to be employed as a diagnostic testing procedure.

Adolescent↗
PubMed2004

Noninvasive imaging of skin tumors.

In this article, the authors review different approaches to the diagnosis of skin tumors using noninvasive diagnostic tools, which are becoming increasingly reliable and, as a consequence, increasingly popular among physicians and patients. Especially in the realm of pigmented skin lesions, dermoscopy and sonography may add useful information to the clinical constellation, improving the diagnostic performance for early diagnosis of melanoma and for differentiating various melanocytic and nonmelanocytic pigmented lesions. More recently, confocal scanning laser microscopy was introduced as a novel technique that enables the in vivo study of the skin at a nearly histologic resolution, being of diagnostic value in various skin disorders, including basal cell carcinoma and pigmented skin lesions. These modalities have various other potential applications besides diagnosis, including lesion's selection for biopsy, determination of appropriate therapeutic modalities, verification of treatment efficacy, and decision of surgical margins. Finally, a hint to the use of cytodiagnosis for basal cell carcinoma is provided.

Basal Cell Carcinoma↗
PubMed2004

Automated extraction and description of dark areas in surface microscopy melanocytic lesion images.

BACKGROUND: Identification of dark areas inside a melanocytic lesion (ML) is of great importance for melanoma diagnosis, both during clinical examination and employing programs for automated image analysis. OBJECTIVE: The aim of our study was to compare two different methods for the automated identification and description of dark areas in epiluminescence microscopy images of MLs and to evaluate their diagnostic capability. METHODS: Two methods for the automated extraction of 'absolute' (ADAs) and 'relative' dark areas (RDAs) and a set of parameters for their description were developed and tested on 339 images of MLs acquired by means of a polarized-light videomicroscope. RESULTS: Significant differences in dark area distribution between melanomas and nevi were observed employing both methods, permitting a good discrimination of MLs (diagnostic accuracy = 74.6 and 71.2% for ADAs and RDAs, respectively). CONCLUSIONS: Both methods for the automated identification of dark areas are useful for melanoma diagnosis and can be implemented in programs for image analysis.

Diagnosis, Differential↗
PubMed2003

Preoperative melanoma thickness determination by 20-MHz sonography and digital videomicroscopy in combination.

OBJECTIVE: To identify accurately thick melanomas preoperatively by means of a combined approach based on sonography and clinical-videomicroscopic evaluation. DESIGN: Ultrasonographic thickness measurement, obtained by means of a 20-MHz B-scanner, and identification of clinical and videomicroscopic variables useful in distinguishing between thick and thin melanomas were performed on a training set of 40 melanomas. An algorithm based on echographic, clinical, and videomicroscopic criteria was constructed to develop a method for preoperative evaluation of melanoma thickness and was validated on a test set of 48 melanomas. SETTING: University medical department. PATIENTS: Eighty-eight patients affected by primary cutaneous melanoma. MAIN OUTCOME MEASURES: Sensitivity and specificity of the algorithm, with the use of sonographic, clinical, and videomicroscopic data, in thick melanoma identification. RESULTS: Echographic thickness was calculated for each lesion. On the training set, 2 clinical and 7 videomicroscopic features were identified for distinction between thick and thin melanomas: nonpalpability, central pigment network, central brown globules, and blotches were characteristic of thin melanomas; clinical regression, localized peripheral pigment network, veil, grayish polygonal areas, and blood vessels were characteristic of thick ones. A coefficient was attributed to each variable and a score was obtained for each lesion. The algorithm, developed for preoperative thickness prediction, was validated on the test set, enabling the distinction of thick melanomas with an 86.7% sensitivity and a 100% specificity. CONCLUSION: The correct classification of all thin melanomas as such renders this approach suitable in clinical practice.

Algorithms↗
PubMed2003

Dermoscopy of pigmented skin lesions: results of a consensus meeting via the Internet.

BACKGROUND: There is a need for better standardization of the dermoscopic terminology in assessing pigmented skin lesions. OBJECTIVE: The virtual Consensus Net Meeting on Dermoscopy was organized to investigate reproducibility and validity of the various features and diagnostic algorithms. METHODS: Dermoscopic images of 108 lesions were evaluated via the Internet by 40 experienced dermoscopists using a 2-step diagnostic procedure. The first-step algorithm distinguished melanocytic versus nonmelanocytic lesions. The second step in the diagnostic procedure used 4 algorithms (pattern analysis, ABCD rule, Menzies method, and 7-point checklist) to distinguish melanoma versus benign melanocytic lesions. kappa Values, log odds ratios, sensitivity, specificity, and positive likelihood ratios were estimated for all diagnostic algorithms and dermoscopic features. RESULTS: Interobserver agreement was fair to good for all diagnostic methods, but it was poor for the majority of dermoscopic criteria. Intraobserver agreement was good to excellent for all algorithms and features considered. Pattern analysis allowed the best diagnostic performance (positive likelihood ratio: 5.1), whereas alternative algorithms revealed comparable sensitivity but less specificity. Interobserver agreement on management decisions made by dermoscopy was fairly good (mean kappa value: 0.53). CONCLUSION: The virtual Consensus Net Meeting on Dermoscopy represents a valid tool for better standardization of the dermoscopic terminology and, moreover, opens up a new territory for diagnosing and managing pigmented skin lesions.

Algorithms↗
PubMed2003

Polarized light-surface microscopy for description and classification of small and medium-sized congenital melanocytic naevi.

Owing to a lack of well-defined clinical criteria for identifying congenital lesions, the diagnosis of small and medium-sized congenital melanocytic naevi is always uncertain. Our aim was to describe the features of small congenital melanocytic naevi, as observed by digital videomicroscopy, with the purpose of identifying single patterns characteristic of small congenital melanocytic naevi or different morphological subgroups. We could then perform a classification based on their macroscopic and surface microscopic aspects. Digital images referring to 154 small congenital melanocytic naevi and to 150 acquired naevi were examined for pattern analysis. New features characterizing small congenital melanocytic naevi, such as target network, target globules, target vessels and focal thickening of network lines, were identified, and a subdivision of small congenital melanocytic naevi into different subgroups was performed. Discriminant analysis enabled the distinction between congenital and common naevi with a sensitivity of 82.5% and a specificity of 64%. Small congenital melanocytic naevi can be described and classified by digital videomicroscopy and pattern analysis. The most important discriminant features are target network, small globules, follicles and vessels. This classification may represent a useful tool in the follow-up of small congenital melanocytic naevi.

Adolescent↗
PubMed2003

A new algorithm for border description of polarized light surface microscopic images of pigmented skin lesions.

The aim of this study was to provide mathematical descriptors for the border of pigmented skin lesion images and to assess their efficacy for distinction among different lesion groups. New descriptors such as lesion slope and lesion slope regularity are introduced and mathematically defined. A new algorithm based on the Catmull-Rom spline method and the computation of the gray-level gradient of points extracted by interpolation of normal direction on spline points was employed. The efficacy of these new descriptors was tested on a data set of 510 pigmented skin lesions, composed by 85 melanomas and 425 nevi, by employing statistical methods for discrimination between the two populations.

Algorithms↗
PubMed2002

Hand dermatitis as an unsuspected presentation of textile dye contact sensitivity.

The aim of this study was to evaluate disperse dye sensitization in patients with hand dermatitis. From January 1996 to December 2000, we identified 130 patients with hand dermatitis reacting to one of the 7 dyes included in our standard series. In 82 subjects the dermatitis was localized to the hands alone, whereas 48 patients had lesions both on the hands and on other skin sites. Disperse Blue dyes, and Disperse Orange 3 were the most common sensitizers. Among the 13 subjects allergic to disperse dyes alone, we found 3 cases of occupational allergic contact dermatitis, 1 child with atopic dermatitis worsening after the use of synthetic fibre garments, 4 subjects affected by clothing dermatitis, and 5 individuals occupationally exposed to irritants with a dermatitis involving the hands alone. In the latter, the hands may represent a 'locus minoris resistentiae', and both induction and elicitation of contact sensitization could be caused by impaired barrier function at a skin site repeatedly exposed to sensitizing garments.

Adolescent↗
PubMedDate not supplied

Sensitization to propolis in 1255 children undergoing patch testing.

To investigate the frequency and the features of contact sensitization to propolis in children, we patch tested 1255 consecutive children suspected of allergic contact dermatitis with propolis 20% petrolatum over an 8-year period (1995-2002). Positive responses were observed in 5.9% of patch-tested subjects, with a significantly higher frequency in boys than in girls. The dermatitis was localized mainly on the face, hands and limbs. A significant linear increase in the annual frequency of propolis allergy was noted. Confirming literature data, a significant association with balsam of Peru sensitivity was present in children reacting to propolis, linked to the presence of common constituents in the 2 substances. In conclusion, based on our data, we suggest that propolis should not be used in topical products for children because of its high sensitization rate at the paediatric age.

Allergens↗
PubMedDate not supplied

Contact sensitization in 1094 children undergoing patch testing over a 7-year period.

Contact sensitization in children is frequent. However, because exposure to sensitizing agents varies rapidly, it is of utmost importance to perform a periodic evaluation of patch test results. Our purpose was to compare our data on contact sensitization in children during the past 7 years to our previous 1988-1994 findings, in order to identify emerging allergens and update our pediatric series. From 1995 to 2001, 1094 consecutive children were examined. Of these, 997 patients were patch tested with our pediatric series, which includes 30 allergens, whereas 97 underwent patch testing with 46 allergens. A total of 570 children proved allergic (52.1%). The highest sensitization rate was observed in children under 3 years of age. No differences between atopic dermatitis patients and nonatopic ones were observed in the sensitization rate. Neomycin, nickel, wool alcohols, thimerosal, and ammoniated mercury gave most of the positive responses. With respect to 1988-1995 data, allergy to substances such as neomycin, nickel, wool alcohols, thimerosal, ammoniated mercury, propolis, potassium dichromate, and thiuram mix proved more frequent. In conclusion, as sensitization rates to different allergens show great variations over time, periodic evaluations of patch test results in children is necessary in order to update the test trays.

Allergens↗
PubMedDate not supplied

Patch testing with egg represents a useful integration to diagnosis of egg allergy in children with atopic dermatitis.

Our aim was to investigate atopy patch and skin prick test reactions to egg in 85 children with atopic dermatitis, and to evaluate their relevance by performing repeated open challenges with egg. Thirty-one percent of our patients showed an eczematous response to the challenge. Positive reactions to atopy patch and skin prick tests were recorded in 37% and 19%, respectively. Atopy patch test sensitivity proved significantly higher than that of skin prick test (79.6% vs. 46.2%), whereas specificity was lower (81.4% vs. 93.2%). Our data suggest that combined skin prick and patch testing improves screening for egg allergy in affected children, identifying 92% of those who were challenge positive among our patients.

Adolescent↗
PubMedDate not supplied

Skin cancer day in Italy: method of referral to open access clinics and tumor prevalence in the examined population.

Education campaigns to encourage self-examination coupled with rapid access to specialized dermatological clinics is considered the key strategy in the realization of early detection of cutaneous melanoma and non-melanoma skin cancer (NMSC). An alternative to an initial visit to the family doctor is open access to a skin cancer clinic at the decision of the individual. This approach has been followed mainly in countries with high melanoma incidence where the majority of the population is of northern European origin. However, the efficacy of this system has not been well established because there are few studies involving systematic follow up of individuals with positive screening through pathological confirmation of the diagnosis. We report the follow up data focussed on melanoma and NMSC detection rates in more than 1,000 subjects examined at numerous 1-day, open access clinics on the occasion of the Italian nation-wide "Skin Cancer Day" campaign promoted by the Federation of Italian Dermatological Societies. Total body skin examination was performed on all subjects, and surgical excision of a lesion was recommended in 41 of the 1042 subjects (3.9 %). Histologic diagnosis, available for 39/41 lesions, evidenced 3 superficial spreading melanomas (1 in situ, one "thin" lesion, ie. 0.30 mm in thickness, and one "thick" lesion, with a thickness of 4.53 mm) and 6 NMSC (5 BCC and 1 SCC). Thus, the prevalence of skin cancer (melanoma and NMSC) in this group was 0.8 % (9/1042), and the prevalence of melanoma was 3/1042, 0.2 %, rather similar to that found in populations of northern European origin. Open access to skin cancer clinics may represent an alternative approach to melanoma prevention also in southern European populations. Increased public awareness regarding skin cancer probably represents the main effect of this type of campaign.

Adult↗