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1.
Cereb Cortex ; 34(1)2024 01 14.
Artículo en Inglés | MEDLINE | ID: mdl-37950876

RESUMEN

The hippocampus, essential for cognitive and affective processes, develops exponentially with differential trajectories seen in girls and boys, yet less is known about its development during early fetal life until early childhood. In a cross-sectional and longitudinal study, we examined the sex-, age-, and laterality-related developmental trajectories of hippocampal volumes in fetuses, infants, and toddlers associated with age. Third trimester fetuses (27-38 weeks' gestational age), newborns (0-4 weeks' postnatal age), infants (5-50 weeks' postnatal age), and toddlers (2-3 years postnatal age) were scanned with magnetic resonance imaging. A total of 133 datasets (62 female, postmenstrual age [weeks] M = 69.38, SD = 51.39, range = 27.6-195.3) were processed using semiautomatic segmentation methods. Hippocampal volumes increased exponentially during the third trimester and the first year of life, beginning to slow at approximately 2 years. Overall, boys had larger hippocampal volumes than girls. Lateralization differences were evident, with left hippocampal growth beginning to plateau sooner than the right. This period of rapid growth from the third trimester, continuing through the first year of life, may support the development of cognitive and affective function during this period.


Asunto(s)
Hipocampo , Imagen por Resonancia Magnética , Masculino , Embarazo , Humanos , Preescolar , Recién Nacido , Femenino , Estudios Longitudinales , Estudios Transversales , Tercer Trimestre del Embarazo , Edad Gestacional , Hipocampo/diagnóstico por imagen , Imagen por Resonancia Magnética/métodos , Feto
2.
Cereb Cortex ; 33(14): 9144-9153, 2023 07 05.
Artículo en Inglés | MEDLINE | ID: mdl-37259175

RESUMEN

The default mode network is essential for higher-order cognitive processes and is composed of an extensive network of functional and structural connections. Early in fetal life, the default mode network shows strong connectivity with other functional networks; however, the association with structural development is not well understood. In this study, resting-state functional magnetic resonance imaging and anatomical images were acquired in 30 pregnant women with singleton pregnancies. Participants completed 1 or 2 MR imaging sessions, on average 3 weeks apart (43 data sets), between 28- and 39-weeks postconceptional ages. Subcortical volumes were automatically segmented. Activation time courses from resting-state functional magnetic resonance imaging were extracted from the default mode network, medial temporal lobe network, and thalamocortical network. Generalized estimating equations were used to examine the association between functional connectivity strength between default mode network-medial temporal lobe, default mode network-thalamocortical network, and subcortical volumes, respectively. Increased functional connectivity strength in the default mode network-medial temporal lobe network was associated with smaller right hippocampal, left thalamic, and right caudate nucleus volumes, but larger volumes of the left caudate. Increased functional connectivity strength in the default mode network-thalamocortical network was associated with smaller left thalamic volumes. The strong associations seen among the default mode network functional connectivity networks and regionally specific subcortical volume development indicate the emergence of short-range connectivity in the third trimester.


Asunto(s)
Red en Modo Predeterminado , Lóbulo Temporal , Embarazo , Humanos , Femenino , Imagen por Resonancia Magnética/métodos , Hipocampo , Encéfalo/diagnóstico por imagen , Mapeo Encefálico
3.
J Hand Ther ; 2023 Sep 29.
Artículo en Inglés | MEDLINE | ID: mdl-37777446

RESUMEN

BACKGROUND: Hand dexterity is an important clinical marker after hand surgery as it can greatly impact one's ability to perform their day-to-day activities. With the increased focus on remote patient monitoring after hand surgery, new technologies are required to remotely monitor hand dexterity. PURPOSE: The purpose of this study is to identify dexterity outcomes using the web application "DIGITS" and compare these outcomes to the nine-hole-pegboard test (NHPT). STUDY DESIGN: Cross-sectional observational study. METHODS: This was a two-part study with a pilot of our remote dexterity design using DIGITS followed by a validation study comparing DIGITS to a gold-standard metric of dexterity, NHPT. The pilot study recruited 42 healthy subjects between the ages of 18-65 to perform a remote finger tapping exercise using DIGITS. The second part of the study included 50 subjects between the ages of 18-65. Participants completed a demographic questionnaire and then completed three finger tapping sequences for 20 seconds using DIGITS and three trials of the NHPT with each hand. Correlational analyses were done to compare the DIGITS dexterity test with the NHPT. RESULTS: Four outcome measures to assess dexterity were identified, which included (1) total sequences completed in 20 seconds, (2) time to complete 10 sequences, (3) average frequency per sequence, and (3) sequence accuracy. Significant negative correlations were found with the NHPT and total sequences completed in 20 seconds in both dominant and non-dominant hand trials. Additionally, significant negative correlations were found between the NHPT and the time to complete 10 sequences and average frequency in the non-dominant hand trials. CONCLUSIONS: This study shows promising results for the use of DIGITS as a remote measure of hand dexterity. The total number of sequences completed significantly correlates with the NHPT and should be further explored in representative patient populations.

4.
Am J Perinatol ; 39(12): 1299-1307, 2022 09.
Artículo en Inglés | MEDLINE | ID: mdl-33374023

RESUMEN

OBJECTIVE: This study aimed to determine whether there are differences in the lateral ventricular volumes, measured by three-dimensional ultrasound (3D US) depending on the posture of the neonate (right and left lateral decubitus). STUDY DESIGN: This was a prospective analysis of the lateral ventricular volumes of preterm neonates recruited from Victoria Hospital, London, Ontario (June 2018-November 2019). A total of 24 premature neonates were recruited. The first cohort of 18 unstable premature neonates were imaged with 3D US in their current sides providing 15 right-sided and 16 left-sided 3D US images. The neonates in the second cohort of six relatively stable infants were imaged after positioning in each lateral decubitus position for 30 minutes, resulting in 40 3D US images obtained from 20 posture change sessions. The images were segmented and the ventricle volumes in each lateral posture were compared with determine whether the posture of the head influenced the volume of the upper and lower ventricle. RESULTS: For the first cohort who did not have their posture changed, the mean of the right and left ventricle volumes were 23.81 ± 15.51 and 21.61 ± 16.19 cm3, respectively, for the 15 images obtained in a right lateral posture and 13.96 ± 8.69 and 14.92 ± 8.77 cm3, respectively, for the 16 images obtained in the left lateral posture. Similarly, for the second cohort who had their posture changed, the mean of right and left ventricle volumes were 20.92 ± 17.3 and 32.74 ± 32.33 cm3, respectively, after 30 minutes in the right lateral posture, and 21.25 ± 18.4 and 32.65 ± 31.58 cm3, respectively, after 30 minutes in the left lateral posture. Our results failed to show a statistically significant difference in ventricular volumes dependence on posture. CONCLUSION: Head positioned to any lateral side for 30 minutes does not have any effect on the lateral ventricular volumes of neonates. KEY POINTS: · Three-dimensional cranial ultrasound can measure neonatal ventricle volume.. · Ventricle volume in each lateral ventricle may be affected by posture of the neonate.. · The 30 minutes in any lateral posture is not sufficient to create volume difference in lateral ventricles..


Asunto(s)
Ventrículos Cerebrales , Imagenología Tridimensional , Ventrículos Cerebrales/diagnóstico por imagen , Ecoencefalografía , Humanos , Imagenología Tridimensional/métodos , Lactante , Recién Nacido , Ventrículos Laterales/diagnóstico por imagen , Ultrasonografía/métodos
5.
J Magn Reson Imaging ; 52(1): 139-145, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-31951084

RESUMEN

BACKGROUND: Functional MRI (fMRI) is a noninvasive method to investigate the neural correlates of brain development. Insight into the rapidly developing brain in utero is limited, and fetal fMRI can be used to gain a greater understanding of the developmental process. Fetal brain fMRI is typically limited to resting-state fMRI due to the difficulty to instruct or provide a stimulus to the fetus. Previous studies have employed auditory task fMRI with an external sound stimulus directly on the abdomen of the mother; however, this practice has since been deemed unsafe for the developing fetus. PURPOSE: To investigate a reliable and safe paradigm to study the development of fetal brain networks, we postulated that an internal task, such as the mother's singing, as the auditory stimulus would result in activation in the fetal primary auditory cortex. STUDY TYPE: Cohort. POPULATION: Pregnant women with singleton pregnancies (n = 9; 33-38 weeks gestational age). FIELD STRENGTH/SEQUENCE: All subjects underwent two task-based block design blood oxygen level-dependent (BOLD) at 1.5T or 3T. ASSESSMENT: Each volume was assessed for fetal motion and manually reoriented and realigned to correct for fetal motion. Once the motion was corrected, a gestational age-matched parcellated atlas with regions of interest overlaid onto the activation map was used to determine which regions in the brain had activation during task phases. STATISTICAL TESTS: First Level Analysis. MRI data were analyzed using SPM 12 as a task fMRI. RESULTS: Eight subjects had activation on the right Heschl's gyrus; six fetuses demonstrated activation on the left when exposed to the internal acoustic stimulus. Additionally, activation was found on the right and left middle cingulate cortex (MCC) and the left putamen. DATA CONCLUSION: Maternal singing can be used as an internal stimulus to activate the auditory network and Heschl's gyrus during fetal fMRI. Level of Evidence 2 Technical Efficacy Stage 2 J. Magn. Reson. Imaging 2020;52:139-145.


Asunto(s)
Corteza Auditiva , Encéfalo , Feto , Estimulación Acústica , Corteza Auditiva/diagnóstico por imagen , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Femenino , Feto/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética , Embarazo
6.
Childs Nerv Syst ; 36(3): 569-575, 2020 03.
Artículo en Inglés | MEDLINE | ID: mdl-31468133

RESUMEN

OBJECTIVE: The aim of this study is to investigate whether ventricular volume in posthemorrhagic ventricle dilatation impacts neurodevelopmental outcome. Infants were scanned with 3D cranial ultrasound in the first few months of life, and their neurodevelopmental outcome at 4, 8, 12, and 24 months corrected age (CA) was examined. METHODS: Forty-nine infants who suffered an intraventricular hemorrhage (IVH) were enrolled in the study. Subjects were scanned multiple times during their stay in the neonatal intensive care unit. Images were manually segmented to measure total volume of the lateral ventricles, and the highest volume was taken. Infants with a volume ≤ 20 cc were considered low-volume (n = 33), and infants with a volume ≥ 40 cc were considered high-volume (n = 12). Developmental outcome was assessed at 4, 8, and 12 months CA with the Alberta Infant Motor Scale (AIMS) and Infant Neurological International Battery (Infanib), and at 24 months CA with the Bayley Scales of Infant Development 3e (BSID III). RESULTS: Infants in the low-volume group had higher scores on the Infanib at 4 months CA, and on both the AIMS and Infanib at 8 and 12 months CA, even after controlling for gestational age, birth weight, and worst grade of IVH. We observed a trend where low-volume infants also scored higher on the cognitive and gross-motor subtests of the BSID III at 24 months CA. CONCLUSION: Our results show that ventricular volume affects neurodevelopmental outcome in infants with IVH. This finding could guide the timing of future interventions, as earlier intervention may decrease the likelihood of adverse neurodevelopmental outcome.


Asunto(s)
Enfermedades del Prematuro , Recien Nacido Prematuro , Hemorragia Cerebral , Niño , Ecoencefalografía , Edad Gestacional , Humanos , Lactante , Recién Nacido
7.
BMC Med Res Methodol ; 17(1): 43, 2017 03 17.
Artículo en Inglés | MEDLINE | ID: mdl-28302050

RESUMEN

BACKGROUND: With the increasing implementation of web-based, mobile health interventions in clinical trials, it is crucial for researchers to address the security and privacy concerns of patient information according to high ethical standards. The full process of meeting these standards is often made more complicated due to the use of internet-based technology and smartphones for treatment, telecommunication, and data collection; however, this process is not well-documented in the literature. RESULTS: The Smart Heart Trial is a single-arm feasibility study that is currently assessing the effects of a web-based, mobile lifestyle intervention for overweight and obese children and youth with congenital heart disease in Southwestern Ontario. Participants receive telephone counseling regarding nutrition and fitness; and complete goal-setting activities on a web-based application. This paper provides a detailed overview of the challenges the study faced in meeting the high standards of our Research Ethics Board, specifically regarding patient privacy. CONCLUSION: We outline our solutions, successes, limitations, and lessons learned to inform future similar studies; and model much needed transparency in ensuring high quality security and protection of patient privacy when using web-based and mobile devices for telecommunication and data collection in clinical research.


Asunto(s)
Seguridad Computacional/estadística & datos numéricos , Confidencialidad/ética , Cardiopatías Congénitas/terapia , Líneas Directas/estadística & datos numéricos , Internet/estadística & datos numéricos , Obesidad/terapia , Telemedicina/métodos , Adolescente , Niño , Ensayos Clínicos como Asunto/métodos , Recolección de Datos , Humanos , Ontario , Teléfono Inteligente/estadística & datos numéricos , Telemedicina/ética
8.
Can J Surg ; 58(2): 87-91, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-25799245

RESUMEN

BACKGROUND: Recognition of tissue planes during surgery appears to be a skill acquired with experience. We conducted a pilot study to test this hypothesis using a novel method for evaluating this skill in a simulated environment. METHODS: Twelve surgeons of varying levels of experience were shown 16 captured images from a mesorectal excision. For each image, they were asked to draw the ideal dissection plane with a stylus on a tablet computer. We used a novel metric for comparing agreement between lines to determine the level of precision observed between junior and senior trainees and consultant surgeons and measure the accuracy of junior and senior trainees compared with consultant surgeons. RESULTS: We observed significant differences in precision for 9 of 16 images; 7 of these followed the predicted stepwise pattern associated with level of experience. Using consultant surgeons as the reference standard, we observed significant differences in accuracy between senior and junior trainees for 11 images, with senior trainees being more accurate in 10 of them. Only 2 images failed to contribute significant findings to our analysis. CONCLUSION: The findings of this pilot evaluation of a novel method for measuring a surgeon's ability to recognize tissue planes in a simulated model show that skill improves with experience. Further evaluation of this method will reveal its utility as an assessment tool and possibly as a training instrument.


Asunto(s)
Competencia Clínica , Procedimientos Quirúrgicos del Sistema Digestivo , Disección , Cirugía General , Humanos , Proyectos Piloto , Percepción Visual
9.
Child Neuropsychol ; : 1-28, 2024 Feb 14.
Artículo en Inglés | MEDLINE | ID: mdl-38353096

RESUMEN

Infantile hydrocephalus considerably impacts neurodevelopment, warranting attention to potential long-term consequences on visuomotor functions. The current study investigated the impact of infantile hydrocephalus on functional connectivity within the posterior cortex. Fourteen patients, who were treated for infantile hydrocephalus, were matched for age and sex with 14 typically-developing controls. Both groups had a mean age of 9 years old. Resting-state functional MRI was used to conduct a functional connectivity analysis within the visuomotor integration network, including the inferior frontal occipital fasciculus, superior longitudinal fasciculus, and frontal aslant tract. Patients had reduced functional connectivity in visuomotor pathways compared to typically-developing children with notable impact on the left and right fusiform gyrus and precuneus. Children with infantile hydrocephalus also performed significantly lower in tasks involving visuomotor integration, visual processing, visuospatial skills, motor coordination, and fine motor manipulation. This study enhances our understanding of the multifaceted impact of infantile hydrocephalus on both neural connectivity and considering behavioral outcomes.

10.
Brain Res Bull ; 206: 110847, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38103800

RESUMEN

OBJECTIVE: The objective of this study was to use probabilistic tractography in combination with white matter microstructure metrics to characterize differences in white matter networks between shunt-treated pediatric hydrocephalus patients relative to healthy controls. We were also able to explore the relationship between these white matter networks and postoperative ventricle volume. METHODS: Network-based statistics was used in combination with whole-brain probabilistic tractography to determine dysregulated white matter networks in a sample of patients with pediatric hydrocephalus (n = 8), relative to controls (n = 36). Metrics such as streamline count (SC), as well as the mean of the fractional anisotropy along a tract, axial diffusivity (AD), mean diffusivity (MD), and radial diffusivity (RD) were assessed. In networks that were found to be significantly different for patients with hydrocephalus, tracts were evaluated to assess their relationship with postoperative lateral ventricle volume. RESULTS: Patients with pediatric hydrocephalus had various networks that were either upregulated or downregulated relative to controls across all white matter measures. Predominately, network dysregulation occurred in tracts involving structures located outside of the frontal lobe. Furthermore tracts with values suggesting decreased white matter integrity were not only found between subcortical structures, but also cortical structures. While there were various tracts with white matter metrics that were initially predicted by lateral ventricle volume, only two tracts remained significant following multiple comparisons. CONCLUSIONS: This cross-sectional study in pediatric patients with hydrocephalus and healthy controls demonstrated using whole-brain probabilistic tractography that there are various networks with dysregulated white matter integrity in hydrocephalus patients relative to controls. These dysregulated networks have tracts connecting structures throughout the brain, and the regions were predominately located centrally and posteriorly. Postoperative ventricle volume did not predict the white matter integrity of many tracts. Future studies with larger sample sizes are needed to further understand these results.


Asunto(s)
Hidrocefalia , Sustancia Blanca , Humanos , Niño , Sustancia Blanca/diagnóstico por imagen , Estudios Transversales , Imagen de Difusión Tensora/métodos , Encéfalo/diagnóstico por imagen , Encéfalo/cirugía , Hidrocefalia/diagnóstico por imagen , Hidrocefalia/cirugía
11.
Front Neurosci ; 18: 1405363, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38887369

RESUMEN

Introduction: Registration to a standardized template (i.e. "normalization") is a critical step when performing neuroimaging studies. We present a comparative study involving the evaluation of general-purpose registration algorithms for pediatric patients with shunt treated hydrocephalus. Our sample dataset presents a number of intersecting challenges for registration, representing the potentially large deformations to both brain structures and overall brain shape, artifacts from shunts, and morphological differences corresponding to age. The current study assesses the normalization accuracy of shunt-treated hydrocephalus patients using freely available neuroimaging registration tools. Methods: Anatomical neuroimages from eight pediatric patients with shunt-treated hydrocephalus were normalized. Four non-linear registration algorithms were assessed in addition to the preprocessing steps of skull-stripping and bias-correction. Registration accuracy was assessed using the Dice Coefficient (DC) and Hausdorff Distance (HD) in subcortical and cortical regions. Results: A total of 592 registrations were performed. On average, normalizations performed using the brain extracted and bias-corrected images had a higher DC and lower HD compared to full head/ non-biased corrected images. The most accurate registration was achieved using SyN by ANTs with skull-stripped and bias corrected images. Without preprocessing, the DARTEL Toolbox was able to produce normalized images with comparable accuracy. The use of a pediatric template as an intermediate registration did not improve normalization. Discussion: Using structural neuroimages from patients with shunt-treated pediatric hydrocephalus, it was demonstrated that there are tools which perform well after specified pre-processing steps were taken. Overall, these results provide insight to the performance of registration programs that can be used for normalization of brains with complex pathologies.

12.
Healthc Technol Lett ; 11(2-3): 117-125, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38638489

RESUMEN

This paper describes a methodology for the assessment of training simulator-based computer-assisted intervention skills on an AR/VR-guided procedure making use of CT axial slice views for a neurosurgical procedure: external ventricular drain (EVD) placement. The task requires that trainees scroll through a stack of axial slices and form a mental representation of the anatomical structures in order to subsequently target the ventricles to insert an EVD. The process of observing the 2D CT image slices in order to build a mental representation of the 3D anatomical structures is the skill being taught, along with the cognitive control of the subsequent targeting, by planned motor actions, of the EVD tip to the ventricular system to drain cerebrospinal fluid (CSF). Convergence is established towards the validity of this assessment methodology by examining two objective measures of spatial reasoning, along with one subjective expert ranking methodology, and comparing these to AR/VR guidance. These measures have two components: the speed and accuracy of the targeting, which are used to derive the performance metric. Results of these correlations are presented for a population of PGY1 residents attending the Canadian Neurosurgical "Rookie Bootcamp" in 2019.

13.
J Child Neurol ; 39(1-2): 66-76, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38387869

RESUMEN

This study investigates structural alterations of the corpus callosum in children diagnosed with infantile hydrocephalus. We aim to assess both macrostructural (volume) and microstructural (diffusion tensor imaging metrics) facets of the corpus callosum, providing insights into the nature and extent of alterations associated with this condition. Eighteen patients with infantile hydrocephalus (mean age = 9 years) and 18 age- and sex-matched typically developing healthy children participated in the study. Structural magnetic resonance imaging and diffusion tensor imaging were used to assess corpus callosum volume and microstructure, respectively. Our findings reveal significant alterations in corpus callosum volume, particularly in the posterior area, as well as distinct microstructural disparities, notably pronounced in these same segments. These results highlight the intricate interplay between macrostructural and microstructural aspects in understanding the impact of infantile hydrocephalus. Examining these structural alterations provides an understanding into the mechanisms underlying the effects of infantile hydrocephalus on corpus callosum integrity, given its pivotal role in interhemispheric communication. This knowledge offers a more nuanced perspective on neurologic disorders and underscores the significance of investigating the corpus callosum's health in such contexts.


Asunto(s)
Cuerpo Calloso , Imagen de Difusión Tensora , Hidrocefalia , Imagen por Resonancia Magnética , Humanos , Cuerpo Calloso/diagnóstico por imagen , Cuerpo Calloso/patología , Hidrocefalia/diagnóstico por imagen , Hidrocefalia/patología , Masculino , Femenino , Imagen de Difusión Tensora/métodos , Niño , Imagen por Resonancia Magnética/métodos , Preescolar , Lactante , Procesamiento de Imagen Asistido por Computador
14.
ScientificWorldJournal ; 2013: 350623, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-24174913

RESUMEN

The intraindividual variability (IIV) of cognitive performance has been shown to increase with aging. While brain research has generally focused on mean performance, little is known about neural correlates of cognitive IIV. Nevertheless, some studies suggest that IIV relates more strongly than mean level of performance to the quality of white matter (WM). Our study aims to explore the relation between WM integrity and cognitive IIV by combining functional (fMRI) and structural (diffusion tensor imaging, DTI) imaging. Twelve young adults (aged 18-30 years) and thirteen older adults (61-82 years) underwent a battery of neuropsychological tasks, along with fMRI and DTI imaging. Their behavioral data were analyzed and correlated with the imaging data at WM regions of interest defined on the basis of (1) the fMRI-activated areas and (2) the Johns Hopkins University (JHU) WM tractography atlas. For both methods, fractional anisotropy, along with the mean, radial, and axial diffusivity parameters, was computed. In accord with previous studies, our results showed that the DTI parameters were more related to IIV than to mean performance. Results also indicated that age differences in the DTI parameters were more pronounced in the regions activated primarily by young adults during a choice reaction-time task than in those also activated in older adults.


Asunto(s)
Envejecimiento/fisiología , Encéfalo/fisiología , Encéfalo/ultraestructura , Cognición/fisiología , Fibras Nerviosas Mielínicas/ultraestructura , Desempeño Psicomotor/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Individualidad , Masculino , Persona de Mediana Edad , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Adulto Joven
15.
Stud Health Technol Inform ; 184: 324-9, 2013.
Artículo en Inglés | MEDLINE | ID: mdl-23400179

RESUMEN

Neuroanatomy is one of the most challenging sections of anatomy to learn, partially related to the intricate relation of multiple 3D structures. As part of the medical student curriculum, it is usually taught in 2D using illustrations and plastinated brain section, since the number of hours devoted to anatomy have dropped in the curriculum, making the dissection of brain too time-consuming to be done. In this study we are analyzing the role of innate spatial ability of novices in learning some basic structures and placing them back in a 3D volumetric brain. Two tasks are performed after a short training session: the first one is to localize the ventricular tip as would be required during a temporal lobectomy, and the second task requires that the subject 'reconstruct' 3D anatomical structures within the context of our 3D brain model. We report our findings on the performance scores obtained from a population of subjects of differing backgrounds and spatial abilities.


Asunto(s)
Encéfalo/anatomía & histología , Instrucción por Computador/métodos , Imagenología Tridimensional/métodos , Modelos Anatómicos , Neuroanatomía/educación , Percepción Espacial/fisiología , Interfaz Usuario-Computador , Simulación por Computador , Evaluación Educacional , Humanos
16.
J Imaging ; 9(2)2023 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-36826939

RESUMEN

This paper presents a discussion about the fundamental principles of Analysis of Augmented and Virtual Reality (AR/VR) Systems for Medical Imaging and Computer-Assisted Interventions. The three key concepts of Analysis (Verification, Evaluation, and Validation) are introduced, illustrated with examples of systems using AR/VR, and defined. The concepts of system specifications, measurement accuracy, uncertainty, and observer variability are defined and related to the analysis principles. The concepts are illustrated with examples of AR/VR working systems.

17.
Medicine (Baltimore) ; 102(11): e33209, 2023 Mar 17.
Artículo en Inglés | MEDLINE | ID: mdl-36930081

RESUMEN

Endovascular surgical procedures require visual-spatial coordination in workspaces with restricted motions and temporally limited imaging. The development of the skills needed for these procedures can be facilitated by 3D simulator-based training. Cerebral angiography (CA) has lagged behind in this training approach due to the lack of validated, realistic training models, relying strictly on clinical case exposure frequency ("number of hours logged") as a means of assessing proficiency. The ANGIO Mentor visual-haptic simulator is regarded as an effective training tool, however, this simulator has not been tested thoroughly in its ability to train interventional skills. In particular, the details of the aneurysm coiling process during simulation-based training have not been assessed. In this study, 12 novice medical students were given simulation-based diagnostic CA training until a procedural plateau in performance, established in our previous work. Subsequently, they were trained using video tutorials and written instructions to identify, measure and intervene with cerebral aneurysms using endovascular coils. Over the span of 6 sessions, participants were assessed on their procedural task time, coiling quantity and quality, and perforation rates. Prior to commencing the study, participant spatial ability was assessed using a mental rotation test (MRT) and used as a comparative baseline for the performance analysis. We found that all individuals were able to perform the procedure faster after 6 sessions, reducing their average time from 42 to 24 minutes. Coil success rate improved over from 82% to 88% and coil packing rate remained consistent at 30% throughout testing. High perforation rate seen at the start of the study showed a trend of decreasing over the latter sessions, however, over half of aneurysms were still being perforated by the novice participants. No change in aneurysm coiling quality was found, with a slight decrease in number of parent artery coil protrusions. High MRT individuals were better able to establish necessary tools prior to coiling, however, no other MRT-specific changes were seen. This work identifies the utility of simulation-based CA training in identifying the particular difficulties trainees experience in learning procedural skills, including prevention of perforations, proper positioning and success of coils within the aneurysm.


Asunto(s)
Procedimientos Endovasculares , Aneurisma Intracraneal , Entrenamiento Simulado , Humanos , Aneurisma Intracraneal/terapia , Aneurisma Intracraneal/cirugía , Entrenamiento Simulado/métodos , Aprendizaje , Evaluación Educacional , Competencia Clínica
18.
Life (Basel) ; 13(7)2023 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-37511962

RESUMEN

BACKGROUND: As pediatric BOLD Signal Variability (SV) analysis is relatively novel, there is a need to provide a foundational framework that gives researchers an entry point into engaging with the topic. This begins with clarifying the definition of BOLD signal variability by identifying and categorizing the various metrics utilized to measure BOLD SV. METHODS: A systematic review of the literature was conducted. Inclusion criteria were restricted to studies utilizing any metric of BOLD SV and with individuals younger than 18 in the study population. The definition of BOLD SV was any measure of intra-individual variability in the BOLD signal. Five databases were searched: Psychinfo, Healthstar, MEDLINE, Embase, and Scopus. RESULTS: A total of 17 observational studies, including male (n = 1796) and female (n = 1324) pediatric participants were included. Eight studies quantified variability as the amount of deviation from the average BOLD signal, seven used complexity-based metrics, three used correlation measures of variability, and one used the structure of the hemodynamic response function. In this study, 10 methods of quantifying signal variability were identified. Associations and trends in BOLD SV were commonly found with age, factors specific to mental and/or neurological disorders such as attention deficit disorder, epilepsy, psychotic symptoms, and performance on psychological and behavioral tasks. CONCLUSIONS: BOLD SV is a potential biomarker of neurodevelopmental and neurological conditions and symptom severity in mental disorders for defined pediatric populations. Studies that establish clinical trends and identify the mechanisms underlying BOLD SV with a low risk of bias are needed before clinical applications can be utilized by physicians.

19.
Front Robot AI ; 10: 1273631, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-38269073

RESUMEN

Smart haptic gloves are a new technology emerging in Virtual Reality (VR) with a promise to enhance sensory feedback in VR. This paper presents one of the first attempts to explore its application to surgical training for neurosurgery trainees using VR-based surgery simulators. We develop and evaluate a surgical simulator for External Ventricular Drain Placement (EVD), a common procedure in the field of neurosurgery. Haptic gloves are used in combination with a VR environment to augment the experience of burr hole placement, and flexible catheter manipulation. The simulator was integrated into the training curriculum at the 2022 Canadian Neurosurgery Rookie Bootcamp. Thirty neurosurgery residents used the simulator where objective performance metrics and subjective experience scores were acquired. We provide the details of the simulator development, as well as the user study results and draw conclusions on the benefits added by the haptic gloves and future directions.

20.
J Neurosurg Pediatr ; 31(4): 321-328, 2023 04 01.
Artículo en Inglés | MEDLINE | ID: mdl-36670532

RESUMEN

OBJECTIVE: Some neonates born prematurely with intraventricular hemorrhage develop posthemorrhagic hydrocephalus and require lifelong treatment to divert the flow of CSF. Early prediction of the eventual need for a ventriculoperitoneal shunt (VPS) is difficult, and early discussions with families are based on statistics and the grade of hemorrhage. The authors hypothesize that change in ventricular volume during ventricular taps that is measured with repeated 3D ultrasound (3D US) imaging of the lateral ventricles could be used to assess the risk of the future requirement of a VPS. METHODS: A total of 92 neonates with intraventricular hemorrhage who were treated in the NICU were recruited between April 2012 and November 2019. Only patients who required ventricular taps (VTs) were included in this study, resulting in the analysis of 19 patients with a total of 61 VTs. Among them, 14 patients were treated with a VPS, and in 5 patients the hydrocephalus resolved spontaneously. Parameters studied were total ventricular volume measured with 3D US, ventricular volume change after VT, the ratio between volume reduction and tap amount, the difference between tap amount and volume reduction after tap, the average tap amount, the average number of days between taps, pre-tap head circumference, and reduction in head circumference after tap. RESULTS: Statistically significant differences were found in ventricular volume reduction after tap (p = 0.007), the ratio between volume reduction and tap amount (p = 0.03), the difference between tap amount and volume reduction after tap (p = 0.05), and the interval of days between taps (p = 0.0115). CONCLUSIONS: Measuring with 3D US before and after VT can be a useful tool for quantifying ventricular volume. The findings in this study showed that neonates who experience a large reduction of ventricular volume after VT are more likely to be treated with a shunt than are neonates who experience a small reduction.


Asunto(s)
Hidrocefalia , Derivación Ventriculoperitoneal , Recién Nacido , Humanos , Derivación Ventriculoperitoneal/efectos adversos , Hidrocefalia/diagnóstico por imagen , Hidrocefalia/etiología , Hidrocefalia/cirugía , Hemorragia Cerebral/complicaciones , Hemorragia Cerebral/diagnóstico por imagen , Ultrasonografía , Drenaje , Estudios Retrospectivos
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