Diagnóstico por la Imagen de las Lesiones Focales de la Calota. Comparación de Modelos Estadísticos y Redes Neuronales
by Estanislao Arana
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(free download) Synopsis
This thesis is dedicated to assess the accuracy of logistic regression (LR) and artificial neural networks (ANN) in the diagnosis of calvarial lesions using computed tomography
(CT). The importance of the different features needed for the diagnosis
in both models is also analyzed. The models were developed using patients
with calvarial lesions as the only known disease were enrolled. All patients
were studied with plain films and CT. Other imaging thecniques were used
when available. The clinical and CT data were used for developing LR and
ANN models. Both models were tested with the jacknife (leave-one-out) method.
The best ANNs were obtained varying iterations and hidden neurons by selecting
the one with higher area under the receiver operating characteristic curve
(ROC). The final results of each model were compared by means of area under
ROC curves. There was no statistically significant difference between LR
and ANN in differentiating benign and malingnant lesions. In characterizing
every histologic diagnoses, ANN was statistically superior to LR (p<0.001).
ANNs were demonstrated adequate to diagnose the most common lesions in
the cranial vault and to help the radiologist with misleading and infrequent
appearances. ANN discover hidden interactions among variables that are
missed in the statistical analysis.