Juan A. Juanes

Experimental evidence for improved neuroimaging interpretation using three-dimensional graphic models.

Three‐dimensional (3D) or volumetric visualization is a useful resource for learning about the anatomy of the human brain. However, the effectiveness of 3D spatial visualization has not yet been assessed systematically. This report analyzes whether 3D volumetric visualization helps learners to identify and locate subcortical structures more precisely than classical cross‐sectional images based on a two dimensional (2D) approach. Eighty participants were assigned to each experimental condition: 2D cross‐sectional visualization vs. 3D volumetric visualization. Both groups were matched for age, gender, visual‐spatial ability, and previous knowledge of neuroanatomy. Accuracy in identifying brain structures, execution time, and level of confidence in the response were taken as outcome measures. Moreover, interactive effects between the experimental conditions (2D vs. 3D) and factors such as level of competence (novice vs. expert), image modality (morphological and functional), and difficulty of the structures were analyzed. The percentage of correct answers (hit rate) and level of confidence in responses were significantly higher in the 3D visualization condition than in the 2D. In addition, the response time was significantly lower for the 3D visualization condition in comparison with the 2D. The interaction between the experimental condition (2D vs. 3D) and difficulty was significant, and the 3D condition facilitated the location of difficult images more than the 2D condition. 3D volumetric visualization helps to identify brain structures such as the hippocampus and amygdala, more accurately and rapidly than conventional 2D visualization. This paper discusses the implications of these results with regards to the learning process involved in neuroimaging interpretation. Anat Sci Educ.

Coexistence of NADPH-diaphorase with tyrosine hydroxylase in hypothalamic magnocellular neurons of the rat

The presence and distribution of NADPH-diaphorase (ND) neurons as well as tyrosine hydroxylase-immunoreactive (TH) neurons in the hypothalamus are well established. Previous studies have shown the coexistence of ND with neuroactive substances such as calbindin, somatostatin, vasopressin and oxytocin in neurons of this region of the brain. As the tópographical patterns of distribution of ND and TH coincide in many cases, the aim of this study was to determine the possible coexistence of both substances in the main hypothalamic magnocellular nuclei of the albino rat. Histochemical-immunocytochemical double labelling was employed on the same sections as well as a morphometric study. NADPH-diaphorase and tyrosine hydroxylase neurons were observed in all the nuclei under study (supraoptic, paraventricular and accessory nuclei), although most neurons showing the coexistence of both substances were mainly located in the supraoptic nucleus, isolated neurons with double labelling being found in the magnocellular parts of the paraventricular nucleus and in some of the accessory nuclei. Although both substances have previously been shown to be modified in hypothalamic neurons after osmotic stimuli, the range of functions of ND in the CNS is only beginning to be understood. Further studies are needed to elucidate the functional role that ND/TH neurons play in the nervous system.

Morphological and Volumetric Assessment of Cerebral Ventricular System with 3D Slicer Software

We present a technological process based on the 3D Slicer software for the three-dimensional study of the brain’s ventricular system with teaching purposes. It values the morphology of this complex brain structure, as a whole and in any spatial position, being able to compare it with pathological studies, where its anatomy visibly changes. 3D Slicer was also used to obtain volumetric measurements in order to provide a more comprehensive and detail representation of the ventricular system. We assess the potential this software has for processing high resolution images, taken from Magnetic Resonance and generate the three-dimensional reconstruction of ventricular system.

Augmented reality techniques, using mobile devices, for learning human anatomy

We present a technological tool we developed under a portable environment by taking a specific fixed image from an anatomy atlas and visualizing it as a three dimensional and dynamic model; an enrichment of the anatomical image and an important aid in the student learning process. The system consists of an augmented reality library called Vuforia. After the images were scanned, they were stored in a database. The three dimensional models seen are created with Unity3D and Maya. The system allows Android and iOS platforms. The use of these mobile devices will allow managing the knowledge for students, developing new ways of teaching innovation and improving the quality of the academic process. These applications encourage student learning, promoting a more interactive attention. There is no doubt that smartphones and tablets are an additional teaching resource nowadays, they enrich and facilitate the transmission of educational contents in health science, specifically in the field of Human Anatomy.

Morphometric changes of specific located vasopressin-reacting parvicellular neurons in the paraventricular nucleus of the rat after adrenalectomy.

The morphological-morphometric consequences of bilateral adrenalectomy on vasopressin-reacting neurons of the paraventricular nucleus of the rat hypothalamus were analyzed. Bilateral adrenalectomy led to a dramatic increase in the cellular area as well as the number of immunoreactive cells (when compared to those obtained in normal colchicine-treated animals) in the neurons located in the anterior, medial and periventricular parvicellular subdivisions of the paraventricular nucleus. By contrast, no changes were observed in either the dorsal or lateral parvicellular subdivisions or in any of the magnocellular subdivisions of the paraventricular nucleus.

Computer Applications in Health Science Education

In recent years, computer application development has experienced exponential growth, not only in the number of publications but also in the scope or contexts that have benefited from its use. In health science training, and medicine specifically, the gradual incorporation of technological developments has transformed the teaching and learning process, resulting in true “educational technology”. The goal of this paper is to review the main features involved in these applications and highlight the main lines of research for the future. The results of peer reviewed literature published recently indicate the following features shared by the key technological developments in the field of health science education: first, development of simulation and visualization systems for a more complete and realistic representation of learning material over traditional paper format; second, portability and versatility of the applications, adapted for an increasing number of devices and operative systems; third, increasing focus on open source applications such as Massive Open Online Course (MOOC).

Digital Environment for Movement Control in Surgical Skill Training

Intelligent environments are increasingly becoming useful scenarios for handling computers. Technological devices are practical tools for learning and acquiring clinical skills as part of the medical training process. Within the framework of the advanced user interface, we present a technological application using Leap Motion, to enhance interaction with the user in the process of a laparoscopic surgical intervention and integrate the navigation through augmented reality images using manual gestures. Thus, we intend to achieve a more natural interaction with the objects that participate in a surgical intervention, which are augmented and related to the user’s hand movements.

Glial fibrillary acidic protein-like immunoreactive ependymal elements in the third ventricle of the rat : a study at different stages of development

Using the peroxidase-antiperoxidase method a study was made of the cells immunoreactive to glial fibrillary acidic protein (GFAP) anti-serum in the ependyma of the third ventricle of the rat at different stages of growth. Most of the ependymal cells of the third ventricle were seen to be unreactive to this protein; however, it was sometimes possible to observe some GFAP-immunoreactive ependymocytes and occasionally other immunoreactive cellular types, such as tanycytes and supraependymal cells. Despite this, the most frequent localization of the elements immunoreactive to the protein adopted the shape of an immunoreactive subependymal band situated parallel to the ventricular wall. As the weights of the animals increased an increase in the elements immunoreactive to this protein could be observed in all the zones considered, there being no differences between the male and female animals.

Analysis of the oculus rift device as a technological resource in medical training through clinical practice

We present a virtual environment for three-dimensional visualization of a hospital operating room, through stereoscopic rendering, using the Oculus Rift headset with a wide field of vision. The application developed allows immersion into an artificial situation where the user can perceive the virtual experience created by the system as real. The system enables the training and familiarization with the different operating room devices and monitors, as well as with the equipment installed. Therefore, an effective training is accomplished as practice for the real situation the user will face.

Computed anatomical modelling of the optic pathway and oculomotor system using magnetic resonance imaging

This study presents a computer-based tool for three-dimensional (3D) visualization of the optic pathway and oculomotor system using 3D high-resolution magnetic resonance imaging (MRI) datasets from a healthy subject. The 3D models were built as wireframe grids co-registered with MRI sections. First, 3D anatomical models were generated of the visual pathway from the eyeball to the primary visual cortex and of the cranial oculomotor nerves from the brain stem to the extrinsic eye muscles. Second, a graphical user interface allowed individual and group visualization, translation, rotation and zooming of the 3D models in different spatial positions simultaneously with MRI orthogonal cut planes. Educational and clinical applications are also discussed.