Preliminary results of a new approach for three-dimensional reconstruction of Dynamic AngioThermography (DATG) images based on the inversion of heat equation.

Dynamic AngioThermography (DATG) is a contact-plate technique capable of producing a digital representation of breast vascularity. The inception and growth of a tumor are associated with neoangenesis, which may result in a demonstrable alteration in the regional blood flow, while in normal health conditions the vascularity remains unchanged throughout life. DATG, if included in the clinical evaluation for breast cancer, could potentially improve the accuracy of the diagnosis of this disease. Conventional DATG is limited, however, in that it is a projection (i.e. two-dimensional) imaging technique that does not provide any information on the depth and its effect on the pattern of the perfusion revealed by this technique. In fact, the blood pattern is detected by projecting temperature signals on the plate, thus acquiring a digital two-dimensional image. In this article we propose a new approach for extracting information on depth through the inversion of the Fourier heat equation. The idea is to extract the information along the third axis while acquiring and analyzing the temporal sequence during the process of image formation. The method implemented has been tested on a dedicated "electric phantom" and in one in vivo experiment. In spite of the limits of these preliminary tests, the experimental results have shown that this method makes it possible to obtain a 3D representation of the vascularity. Although it appears to be promising, further validation and characterization of our technique are required.

Dental status and 3D reconstruction of the malocclusion of the famous singer Farinelli (1705-1782).

The famous castrato singer Carlo Broschi, better known as Farinelli (1705-1782), was exhumed by our research group in July 2006 to study his skeletal remains and reconstruct his osteobiography. He was castrated before puberty to preserve his high voice into adulthood. The osteological study has revealed several skeletal features probably related to the effects of castration (Hyperostosis frontalis interna, long limb bones, persistence of epiphyseal lines, osteoporosis) (Belcastro et al., 2011). Here we present the study of the teeth and maxilla-mandibular region using classic and tomographic morphological methods. Considering the subject's age and the period during which he lived, his oral health conditions were good. On the basis of the very pronounced anomalous vestibular buccal wear, a overbite visualized by 3D reconstruction, was hypothesized. This facial disharmony is of particular interest when considering Farinelli's extraordinary singing qualities and stage presence.

An SVM classifier to separate false signals from microcalcifications in digital mammograms.

In this paper we investigate the feasibility of using an SVM (support vector machine) classifier in our automatic system for the detection of clustered microcalcifications in digital mammograms. SVM is a technique for pattern recognition which relies on the statistical learning theory. It minimizes a function of two terms: the number of misclassified vectors of the training set and a term regarding the generalization classifier capability. We compare the SVM classifier with an MLP (multi-layer perceptron) in the false-positive reduction phase of our detection scheme: a detected signal is considered either microcalcification or false signal, according to the value of a set of its features. The SVM classifier gets slightly better results than the MLP one (Az value of 0.963 against 0.958) in the presence of a high number of training data; the improvement becomes much more evident (Az value of 0.952 against 0.918) in training sets of reduced size. Finally, the setting of the SVM classifier is much easier than the MLP one.

Are barrier creams actually effective?

This article reviews the current information surrounding the efficacy of barrier creams as a protective measure against contact dermatitis. The principles of the proposed effects of barrier creams on the skin and the experimental and clinical data regarding their efficacy in the prevention of irritant and allergic contact dermatitis are discussed.

Delayed type hypersensitivity to intralesional triamcinolone acetonide.

Corticosteroids are the most widely used class of drugs in dermatology. In the past, allergic contact dermatitis to topical corticosteriods was rarely reported. In this article, we present a case of delayed type hypersensitivity to triamcinolone acetonide.

Allergic contact and photoallergic contact dermatitis to plant and pesticide allergens.

BACKGROUND: The panel of patch test allergens used for the evaluation of patients with suspected photoallergy typically does not include plant and pesticide allergens. The prevalence of allergic contact dermatitis and photoallergic contact dermatitis to plant and pesticide allergens was determined for this subgroup of patients. OBSERVATION: Positive reactions were detected in 12 of 26 patients who were tested with our photoallergen series: 5 with allergic contact dermatitis, 5 with photoallergic contact dermatitis, and 2 with both. Four of the 12 patients had positive patch and photo-patch test reactions to plant allergens, pesticide allergens, or both. The positive patch test reactions were to the plants Taraxacum officinale (dandelion) and Tanacetum vulgare (tansy) and to the pesticides folpet and captafol. Positive photo-patch test reactions were to the pesticides folpet and captan. The histories of the patients suggested that 2 or 3 of the 4 patients had clinically relevant reactions. In the other 8 patients, positive reactions to the patch and photo-patch tests included fragrances, sunscreens, and antibacterial agents. CONCLUSION: Plant and pesticide allergens should be included in the patch and photo-patch test series used for the evaluation of patients with suspected photoallergy.

Six-hour versus 48-hour patch testing with varying concentrations of potassium dichromate.

This study examines the possibility of using patch contact times shorter in duration than the standard 48 hours. Using varying concentrations of potassium dichromate (K2Cr2O7), this study analyzed results from two sets of patches applied to the backs of 11 subjects for durations of 6 and 48 hours, respectively. Results showed that after the 48-hour application period, all subjects reacted to K2Cr2O7 at some concentration. For the patches applied for 6 hours, 7 of the 11 subjects (64%) reacted to K2Cr2O7 at some concentration. Minimum elicitation thresholds (METs), the lowest concentration at which a reaction was observed, were established for both the 6-hour and 48-hour application times. The ratio of an individual's 6-hour MET to their 48-hour MET was calculated to evaluate the feasibility of patch testing with a higher concentration of an allergen for a shorter time period. Although the results clearly indicated that a higher concentration of allergen is required in order to elicit a reaction at 6 versus 48 hours, a fair amount of interindividual variability is exhibited by these 6-hour to 48-hour MET ratios. This observed variability would seem to preclude the use of 6-hour duration patch contact times for routine patch testing with K2Cr2O7.

Utility of a standard allergen series alone in the evaluation of allergic contact dermatitis: a retrospective study of 732 patients.

BACKGROUND: Patch testing remains the standard for the diagnosis of allergic contact dermatitis. The validity and usefulness of a standard patch test allergen series has not been addressed adequately by previous studies. OBJECTIVE: We sought to examine the utility of the standard allergen series as a sole screening tool in the diagnosis of allergic contact dermatitis. METHODS: The charts of 732 patients referred for patch testing were reviewed for positive patch test results. The group of patients with positive reactions was stratified into two groups based on the clinical relevance of their reactions. These groups were subsequently analyzed to determine whether the reactions were to part of the standard series of allergens or to part of a supplementary group. RESULTS: Of patients tested, 50% had a positive patch test. Of those, 221 (30%) had reactions deemed clinically relevant. Only 23% of patients with positive patch tests reacted to an allergen(s) in the standard series exclusively. When adjusted for clinical relevance, only 15.7% of patients were completely evaluated with the standard series of 20 allergens. CONCLUSION: The standard allergen series of 20 allergens available in the United States is limited as a screening tool when used alone in the evaluation of patients with allergic contact dermatitis.

What is new in clinical research in contact dermatitis.

The field of cutaneous allergy has enjoyed dynamic research advances in epidemiology and clinical contact dermatitis. Studies regarding outcomes analysis, validity, predictive value, and sensitivity have allowed clinicians to better understand the importance of patch test results. In the clinical arena, new and clinically relevant allergens are being discovered, such as corticosteroids, metals, preservatives, surfactants, and glues. Continued epidemiologic surveillance of new allergens will enable manufacturers to develop safer products for patients to use.

Iatrogenic contact dermatitis to proparacaine: an ophthalmic topical anesthetic.

Allergic contact dermatitis to a topical ophthalmic anesthetic, proparacaine, is reported in a patient with refractory glaucoma. His ophthalmologist routinely used a preparation containing this anesthetic, which is an uncommon sensitizer, for measuring the patient's intraocular pressure. That the patient did not apply the medication himself resulted in added difficulty in discovering the iatrogenically induced contact allergy. Avoidance of this anesthetic resulted in resolution of the patient's recurrent bouts of periocular dermatitis and conjunctivitis. The importance of testing patients suspected of having contact allergy to all medications to which they are exposed is emphasized.

Allergic contact dermatitis from color film developers: clinical and histologic features.

We evaluated two patients with allergic contact dermatitis that resulted from exposure to color film developers. A lichenoid eruption developed in one patient, whereas an eruption more characteristic of an acute spongiotic dermatitis developed in the second patient. Histologic findings in the first case were those of a "lichenoid dermatitis" but with features distinct from classic lichen planus. The biopsy specimens from the second patient showed a subacute spongiotic process with a bandlike infiltrate suggestive of an evolving lichenoid process. Contact allergy to color developers may result in eruptions similar to lichen planus. This process appears to evolve from an acute spongiotic dermatitis in its early phase to a lichenoid dermatitis in fully developed and more chronic forms. Although the histologic features are those of a "lichenoid" dermatitis, some features, such as the presence of spongiosis, eosinophils, and a less intense inflammatory infiltrate, may enable distinction between lichenoid allergic contact dermatitis and true lichen planus. In addition, clinicopathologic correlation with patch test results should permit accurate diagnosis in most cases.

American Academy of Dermatology Patch Testing Survey: use and effectiveness of this procedure.

The results of an American Academy of Dermatology (AAD)-sponsored survey on the use and effectiveness of patch testing are presented. Academy members' responses indicate that 27% do not patch test at all. Reasons given for not testing included (1) the patient history was adequate for diagnosis, (2) patch testing was too time-consuming, and (3) reimbursement was not sufficient. Dermatologists in residency training programs who responded to a similar survey are testing frequently and report a high degree of positivity and relevancy among tests applied. Recommendations are presented with a focus toward increasing interest in patch testing among the membership.

Alstroemeria. A new and potent allergen for florists.

Alstroemeria (Peruvian or Inca lily) has found particular favor because of its beauty and durability. However, it may induce a dermatitis so severe that workers have to change jobs. The dermatitis is chronic, with fissuring at the tips of the fingers bilaterally. Itching is often a less prominent symptom. Preventative measures are of little benefit, and many floral shops are vanishing the plant.