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E Vacca

Publications and source records attributed to E Vacca.

15 recordsLinked to original sources
PubMed1992

Laryngeal intraepithelial neoplasia (LIN). An analytical morphometric approach.

Laryngeal Intraepithelial Neoplasia (LIN) is graded in 3 levels (LIN Grade I-II-III), corresponding to the classic aspects of mild, moderate and severe dysplasia-in situ carcinoma, on the basis of the number and position of mitoses and of the undifferentiated or atypical cells limited to the basal or extended to the intermediate or the superficial layers of epithelium. In order to reduce the subjective imprecision of these parameters we have applied not only traditional dimensional evaluators but also procedures of analytical morphometry to the nuclear shape. By using the software system S.A.M. (Shape Analytical Morphometry) we have examined fifty nuclei of the basal layer in LIN grade I, II and III, fifty nuclei in normal laryngeal mucosa and fifty nuclei in invasive carcinoma of the larynx (twenty-five cases in all). Normal and dysplastic nuclei did not show any dimensional differences, while the carcinomatous nuclei were significantly larger. An asymmetric distortion of the nuclear contour was noted in the moderate and severe dysplasia, but not in carcinomatous cells. Also the Fourier parameters, increased in severe dysplasia, decreased dramatically in carcinomatous cells which showed nuclei with minor contour irregularities than the normal cells. These findings outline the discriminative power of the analytical morphometry and suggest a possible correlation between nuclear shape and cell biology.

Carcinoma in Situ↗
PubMed1992

Biological image analysis for microscopical diagnosis: the work-station S.A.M. (Shape Analytical Morphometry).

The S.A.M. (Shape Analytical Morphometry) software system and its related work-station give a generalized and easy-to-handle tool to face a classic and intriguing problem in biomedical morphological diagnosis. What is the shape of an object in a microscopic image? How can we understand the relationship between size and shape? According to Holloway: "Measurements such as length, width, height, whether in chords or arcs only describe space, ... and further run into the abyss of allometric correction ... if additional information (shape?) to size is expected, some method of allometric correction must be used." The S.A.M. software system assumes a logic architecture able to separate and to parametrize independently shape characteristics in terms of allometry and local pertubation by analytical procedures (polynomials, parabolic fitting, Fourier analysis) in addition to the classic evaluations of size and density carried out by image analyzers for microscopical diagnosis.

Diagnosis, Computer-Assisted↗
PubMed1992

Multiparametric discrimination of serous ovarian tumors by analytical morphometry.

In order to enhance the discrimination power in the field of serous ovarian tumors, we applied the software system SAM (Shape Analytical Morphometry) to the analytic studies of biological forms. Besides the usual dimensional evaluations (perimeter, area, maximum diameter and shape index), this procedure permits the description of the nuclear form using analytical parameters: 1) extraction of nucleus fundamental curve; that is a functional curve giving the "smoothing" of the original contour by two parametric equations (separately for x and y values as independent variables); 2) evaluation of nuclei contour irregularities by Fourier analysis; 3) evaluation of shape asymmetry by SAE (Shape Asymmetry Evaluator); that is the ratio between the length of a segment of a parabola interpolating the original curve points, and a straight line joining its extremities for a 180 degrees barycentric rotation according 10 degrees steps. All parameters resulted to be independent and were submitted to multivariate discriminant analysis. We studied 180 nuclei from 18 cases of serous ovarian tumors, (6 benign, 6 borderline and 6 malignant tumors). With respect to the dimensional parameters, the application of analytical morphometry permitted us to reduce the minimum percentage error in the discrimination of the different classes. In fact, in the distinctions of benign and malignant nuclei, the minimum percentage error was 13.30%, against the 18.3% error when using dimensional morphometry. Furthermore, in the comparison of malignant and borderline nuclei there was a reduction of error from 23.3% to 22.5%, and in the comparison of benign and borderline nuclei, the error was reduced from 37.5% to 30%.(ABSTRACT TRUNCATED AT 250 WORDS)

Cell Nucleus↗
PubMed1991

Analytical morphies on mid-sagittal craniograms glabella-opisthocranion of Homo erectus and Homo sapiens neanderthalensis: Fourier parameters and synthesis of mean craniograms.

Among mathematic procedures used in morphological description, Fourier analysis was indicated as extremely effective in obtaining numerical representations of shape. In order to fully exploit its potentiality in morphology the worked data have to be referred exclusively to the shape of the investigated object and the application of suitable procedures of dimensional normalization are necessary, moreover the significance of the parameters obtained from the analysis must be referable univocally to the morphological datum. In these conditions the numerical characterization of shapes and the relations detectable from different parameters obtained from the description assume the significance of real "analytical morphies". These statements were verified by performing morphological description and comparison, by means of the Fourier harmonic analysis on two groups of mid-sagittal glabella-opisthocranIon craniograms to point out their possible distinctive analytical characteristics: the first group relates to classical neanderthalian group, the second one is made up of asiatic samples of Homo erectus. Some typical patterns of the obtained parameters were discussed and explained in terms of analytical morphies characterizing the given specimens, the traditional morphological classifications were verified and, above all, a numerical description of these samples was obtained.

Animals↗
PubMed1991

Analytical morphies on mid-sagittal craniograms glabella-opisthocranion of Homo erectus and Homo sapiens neanderthalensis: Fourier parameters and multivariate discriminant analysis.

The analytical description of complicated morphologies offers the possibility to define patterns of parameters characterizing the investigated groups. These patterns must be considered as morphies useful in performing classification and comparison. Fourier parameters are extremely effective in describing and comparing complex irregular forms and since they are statistically independent we can use them in performing multivariate discriminant analysis. Two groups of mid-sagittal craniograms glabella-opisthocranion of asiatic samples of Homo erectus and of Homo sapiens neanderthalensis were described by means of Fourier harmonic analysis. The discriminatory power of all the obtained parameters (coefficients, amplitudes and phases) was tested. A discriminant function (error % = 0) was obtained using as parameters the first 4 sine/cosine coefficients, the 5th sine, the 6th and the 7th cosine components (11 parameters in all). When the information contained in the coefficient values is being subdivided into the two components of amplitude and phase, the amplitude component is not able to discriminate between the two groups (error % = 25), while the phase values of the first 7 harmonics are able to discriminate them (error % = 0 and distance between centroids = 47).

Animals↗
PubMed1990

[Nuclear morphometry and estrogen receptors in infiltrating ductal carcinoma of the breast].

In this study ten cases of breast infiltrating ductal carcinoma have been considered. In all of them the content of ER has been evaluated by using monoclonal antibodies. Five of them were ER positive and five were ER negative. For the morphometric study ten nuclei of each case have been considered. By using the S.A.M. (Shape Analytical Morphometry) work-station an analytical study of the nuclear shape was performed. The first step was the extraction of fundamental shape which describes the basic shape of original contour without its irregularities. It was obtained by using two parametric equations. The second step was the evaluation of shape asymmetry by S.A.E. (Shape Asymmetry Evaluator). Finally the contour irregularities were evaluated by Fourier analysis. Along with analytical parameters, dimensions (area, perimeter and maximum diameter) were considered too. All obtained data were submitted to univariate statistical analysis (Student's T test) to compare the two groups (ER positive and ER negative tumors). Area, perimeter and maximum diameter were significatively greater in ER negative cases while analytical parameters were not discriminant between the two groups.

Breast Neoplasms↗
PubMed1990

[Vectorial description of the horizontal craniogram].

After the polynomial approximation we used Bezier's algorithm to obtain a vectorial description and to compare the horizontal craniogram morphology of hominid skulls. A minimum number of determinant points chosen on the original curves constitutes the vertices of a closed polygonal. By these points Bezier's interpolation gives new curves very similar to the polynomial curves obtained by the original ones. Each pair of consecutive segments was used to construct a parallelogram and so to have a vector. We applied the procedure on horizontal craniograms of Sts V. Pithecanthropus (erectus) VIII (Sartono), Circeo I (after S. Sergi) and a modern human female skull. Ten vectors for each skull were detected and compared. Some similarities in frontal and posterior regions of P VIII and Circeo I were explained in terms of common morphological solution to the problem of mechanical stability in the skulls with pronounced platycrany under chewing load.

Algorithms↗
PubMed1990

[Quantitative evaluation of the allometric transformation of of biological structures].

Detection and quantification of allometry is a crucial problem in understanding morphological changes, both for systematic and morphogenetic purposes. A section of S.A.M. (Shape Analytical Morphometry) software system was used for this attempt. It consists of the following steps: a) boundary detection; b) starting point detection; c) size normalization; d) extraction of the fundamental shape by Kth order polynomials; e) finding of symmetry evaluator (S.A.E.) by means of a second degree equation. This last procedure gives an arc-chord complex that expresses a vector for allometry where intercept value was for application point, first degree coefficient was for direction and second degree coefficient was for modulus and versus. The main parameters, isometry fraction and allometry fraction may be understood referring them to morphogenetic models.

Algorithms↗
PubMed1989

Differential diagnosis between thyroid follicular adenoma and carcinoma. Analytic morphometric approach.

In this study some nuclear dimensional and analytical parameters were evaluated in order to distinguish follicular atypical adenoma from follicular carcinoma of the thyroid. Eighty nuclei from carcinomas, 80 from adenomas and 80 from normal thyroid were studied. Analytical parameters obtained by the nuclear shape study (by S.A.M. system) as well as dimensional parameters were submitted to univariate statistical analysis. On the ground of our results atypical adenoma could be considered as an intermediate aspect of a progressive change from benign to malignant even if they are closer to normal thyroid than to carcinoma.

Adenocarcinoma↗
PubMed1986

Computer-aided skull/face superimposition.

By use of a special optical device coupled with a TV camera to match a skull and a photograph of a face, superimposition for the purpose of personal identification was performed in controlled situations. A computer-aided method to evaluate the fit of the superimposition has been outlined by means of an original Shape Analytical Morphometry (SAM) software package yielding analytical descriptions by kth-order poly-nominal equations and Fourier harmonic analysis. The match was carried out by using point-cross error and sum of differences for the Fourier set amplitude. A final comprehensive evaluation exhibited marked differences between congruent and noncongruent superimpositions.

Face↗
PubMed1985

[Parameters of analytic morphometry: proposal for a symmetry evaluator].

A morphometrical analytical evaluator of asymmetries of biological structures bonded by a closed curve was suggested. A second degree equation couple was found in order to detect, respectively according X and Y axis, first main asymmetry whereas third degree equation revealed first and second asymmetry for both abscissa and ordinate values. Final evaluator, named S.A.E. (Shape Analytical Evaluator), was computed as arch/cord ratio between function curve and its cord, it was equal to 1 for circles and any ellipse and symmetrical shapes whereas it was of different value for asymmetrical shapes.

Anthropometry↗