A computer model of adaptive segmentation of two-dimensional visual objects was developed, based on neurophysiological and psychophysiological principles. The model imitates several stages of visual information processing. At the first stage, a preliminary assessment of the image is performed using a brightness pattern analyzer. At the second stage, control parameters are formed on the bases of the initial assessment. A defined control vector is synthesized for each type of starting image, which allows adaptive processing; this initiates two parallel mechanisms of primary image description: one contains the outlines of images and the sharp boundaries between their fragments, and the second contains areas of uniform intensity. The control parameter vector is applied to these two descriptions to analyze their brightnesses and spatial characteristics, and this is used as the basis for forming the regime for subsequent processing, which includes a set of processing operators whose parameters are tuned for each fragment of the image. The primary phasic and tonic descriptions are then used to extract individual fragments of the image (i.e., discrimination of figures from the background) and to form the final presentation. The resulting descriptions complement each other, creating a basis for quantitative measurements of image characteristics and allowing various signs needed for image classification to be formed. The computer program for adaptive image segmentation was tested using a large number of different two-dimensional half-tone objects, the purposes of these exercises including segmentation and measurement of objects in morphometric and cytometric studies.
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Biomed Phys Eng Express
January 2025
National School of Electronics and Telecommunication of Sfax, Sfax rte mahdia, sfax, sfax, 3012, TUNISIA.
Deep learning has emerged as a powerful tool in medical imaging, particularly for corneal topographic map classification. However, the scarcity of labeled data poses a significant challenge to achieving robust performance. This study investigates the impact of various data augmentation strategies on enhancing the performance of a customized convolutional neural network model for corneal topographic map classification.
View Article and Find Full Text PDFGac Med Mex
January 2025
Laboratorio de Reprogramación Celular y Enfermedades Crónico-Degenerativas, Department of Physiology, Universidad Nacional Autónoma de México, Mexico City, Mexico.
Progressive supranuclear palsy (PSP) is a rare, atypical parkinsonism, characterized by the presence of intracerebral tau protein aggregates and determined by a wide spectrum of clinical features. The definitive diagnosis is postmortem and is identified through the presence of neuronal death, gliosis, and aggregates of the tau protein presented in the form of neurofibrillary tangles (MNF) with a globose appearance in regions such as the subthalamic nucleus, the substantia nigra, and the globus pallidus The findings in ancillary imaging studies, as well as fluids biomarkers, are not sufficient to support diagnosis of PSP but are used to rule out similar pathologies because there are still no specific or validated biomarkers for this disease. The current treatment of PSP is focused on reducing symptoms, although emerging therapies seek to counteract its pathophysiological mechanisms.
View Article and Find Full Text PDFJ Neurosurg Case Lessons
January 2025
Neurosurgery Department, Palmetto General Hospital, Hialeah, Florida.
Background: Astroblastoma is an extremely rare tumor of the central nervous system, and its origin and validity as a different entity are still being debated. Because of its rarity and similarities to other glial neoplasms, it is often misdiagnosed, impacting treatment and outcomes.
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J Neurosurg Case Lessons
January 2025
Department of Neurosurgery, Kanto Rosai Hospital, Kanagawa, Japan.
Background: The presence of significant tortuosity in access routes to aneurysms can interfere with catheter guidance and manipulation and significantly impact treatment strategies.
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J Neurosurg Case Lessons
January 2025
Department of Neurological Surgery, Cooper University Health Care, Camden, New Jersey.
Background: External ventricular drains (EVDs) provide an invaluable diagnostic method for accessing cerebrospinal fluid and therapeutically treating elevated intracranial pressure. Although complications including hemorrhage and infection have been well documented, the formation of iatrogenic pseudoaneurysms following EVD placement has rarely been reported. The authors present a case of this exceedingly rare complication of iatrogenic pseudoaneurysm formation following EVD placement.
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