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3.
5.
Sci Rep ; 12(1): 8617, 2022 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-35597795

RESUMEN

The objective of this study was to characterize head biomechanics of video-recorded falls involving young children in a licensed childcare setting. Children 12 to < 36 months of age were observed using video monitoring during daily activities in a childcare setting (in classrooms and outdoor playground) to capture fall events. Sensors (SIM G) incorporated into headbands worn by the children were used to obtain head accelerations and velocities during falls. The SIM G device was activated when linear acceleration was ≥ 12 g. 174 video-recorded falls activated the SIM G device; these falls involved 31 children (mean age = 21.6 months ± 5.6 SD). Fall heights ranged from 0.1 to 1.2 m. Across falls, max linear head acceleration was 50.2 g, max rotational head acceleration was 5388 rad/s2, max linear head velocity was 3.8 m/s and max rotational head velocity was 21.6 rad/s. Falls with head impact had significantly higher biomechanical measures. There was no correlation between head acceleration and fall height. No serious injuries resulted from falls-only 1 child had a minor injury. In conclusion, wearable sensors enabled characterization of head biomechanics during video-recorded falls involving young children in a childcare setting. Falls in this setting did not result in serious injury.


Asunto(s)
Aceleración , Cuidado del Niño , Fenómenos Biomecánicos , Estatura , Niño , Preescolar , Cabeza , Humanos , Lactante
6.
Proc Natl Acad Sci U S A ; 119(19): e2121660119, 2022 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-35503912

RESUMEN

SignificanceIn visually active animals, eye, head, and body movements are coordinated to direct gaze. Given their distinct mechanics, how does the nervous system weight their contribution? By combining experiments in flying flies with control theory, we show that flies implement an elegant solution to this problem: the lower inertia head is recruited for higher-frequency visual tasks and is sensitive to motion acceleration, whereas the higher inertia body is recruited for lower-frequency visual tasks and is sensitive to motion velocity. This complementary division of labor within the nervous system exhibits two hallmarks of optimality: an increase in task performance accompanied with a decrease in mechanical energy expenditure. Our model recapitulates classic primate head-eye coordination responses, suggesting convergent mechanisms across phyla.


Asunto(s)
Movimientos de la Cabeza , Cabeza , Animales , Movimientos Oculares , Retroalimentación , Cabeza/fisiología , Movimientos de la Cabeza/fisiología , Movimiento (Física)
7.
Neuroimaging Clin N Am ; 32(2): 271-277, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35526955

RESUMEN

Computed tomography (CT) artifacts are aberrations that usually degrade the image quality of CT images, but occasionally provide insights regarding actual imaging findings. The presence of artifacts can be attributed to various sources, including patient, scanner, and postprocessing factors. Artifacts can lead to diagnostic errors by obscuring findings or by being misinterpreted as actual lesions. This article reviews various types of CT artifacts that can be encountered in the head and neck region and explain how these artifacts may be mitigated. While we cannot fully eliminate the occurrence of CT artifacts, building an awareness of their cause provides reading physicians the tools to detect and read through their presence. Further, this knowledge may be applied to contribute to protocol adjustments to improve a site's overall imaging practice.


Asunto(s)
Artefactos , Tomografía Computarizada por Rayos X , Cabeza/diagnóstico por imagen , Humanos , Cuello/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos
8.
Neuroimaging Clin N Am ; 32(2): 279-286, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35526956

RESUMEN

MR Imaging artifacts are features appearing in MR images that are not present in the original anatomy. MR imaging artifacts can be patient-related, hardware-related, or signal-processing-related and affect diagnostic quality or mimic pathology. It is necessary to take MR imaging artifacts into consideration when interpreting images. A basic knowledge of MR imaging physics and the potential origin of MR imaging artifacts can help to find solutions to eliminate or reduce the influence of artifacts on image quality by adjusting acquisition parameters appropriately for a better diagnosis.


Asunto(s)
Artefactos , Imagen por Resonancia Magnética , Cabeza/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Cuello
9.
Neuroimaging Clin N Am ; 32(2): 299-313, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35526958

RESUMEN

Surgical procedures and radiation therapy can have recognizable features on diagnostic imaging that should be recognized by the radiologist. Although it is a good practice to reference the surgical and clinical notes regarding any procedures that may have been performed in the head and neck, this information is not always available. Selected examples of posttreatment findings and potential mimics are described and depicted in the following sections.


Asunto(s)
Neoplasias de Cabeza y Cuello , Diagnóstico por Imagen , Cabeza/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/radioterapia , Neoplasias de Cabeza y Cuello/cirugía , Humanos , Cuello/diagnóstico por imagen
10.
Neuroimaging Clin N Am ; 32(2): 315-326, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35526959

RESUMEN

A wide variety of foreign bodies can be encountered on head and neck imaging. These foreign bodies might include comestible foreign bodies, retained foreign bodies from trauma, and surgically implanted devices. The imaging features of these items are reviewed in this article.


Asunto(s)
Cuerpos Extraños , Cuello , Diagnóstico por Imagen , Cuerpos Extraños/diagnóstico por imagen , Cuerpos Extraños/cirugía , Cabeza/diagnóstico por imagen , Humanos , Cuello/diagnóstico por imagen
11.
Neuroimaging Clin N Am ; 32(2): 391-412, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35526964

RESUMEN

The vasculature of the neck, comprised of arteries and veins, provides for the supply and return of blood to and from the brain, and to structures of the neck and face. Knowledge of normal appearance and anatomy, and anatomic variants, may help one distinguish between normal and pathologic processes in the neck, which may affect diagnosis or choice of surgical approach. Other related structures that are important to recognize include the thoracic duct and carotid body. In this article examples of mostly computed tomography and MR imaging of normal anatomy and some of these variants are shown.


Asunto(s)
Cabeza , Cuello , Cabeza/anatomía & histología , Cabeza/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Cuello/anatomía & histología , Cuello/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos
12.
Neuroimaging Clin N Am ; 32(2): 433-445, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35526966

RESUMEN

Children present with a spectrum of head and neck pathologies that differ from those found in the adult population, with specific image findings and clinical characteristics. This article reviews the imaging protocols, pearls and pitfalls, and mimics of pediatric head and neck lesions, stressing the combination of key radiological findings, clinical presentation, and anatomic localization necessary to correctly interpret the imaging.


Asunto(s)
Neoplasias de Cabeza y Cuello , Adulto , Niño , Cabeza/diagnóstico por imagen , Neoplasias de Cabeza y Cuello/diagnóstico por imagen , Humanos , Imagen por Resonancia Magnética/métodos , Cuello/diagnóstico por imagen
16.
Neurol India ; 70(2): 475-477, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35532606
17.
JAMA ; 327(18): 1748, 2022 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-35536279
18.
Zhongguo Yi Xue Ke Xue Yuan Xue Bao ; 44(2): 181-187, 2022 Apr.
Artículo en Chino | MEDLINE | ID: mdl-35538751

RESUMEN

Objective To investigate the clinical and magnetic resonance imaging(MRI) manifestations of Rosai-Dorfman disease(RDD) in central nervous system. Method The clinical and MRI data of 5 cases of RDD in central nervous system confirmed by pathology in the PLA General Hospital were analyzed retrospectively. Results The 5 cases included 4 males and 1 female,aged(39.8±21.7) years on average.Among them,4 cases were located in the intracranial area and 1 case in the thoracic spinal canal.The lesion showed isointense signal on T1 weighted image and iso,slight-hypo,and slight-hyperintense signals on T2 weighted image,and it presented intensively homogeneous enhancement in contrast-enhanced MRI.Two cases showed compressed brain area with edema around the left parietal and left frontotemporal dura,thickening and enhancement in the adjacent dura,and dural tail sign.Three cases presented bone destruction in adjacent diploe and thoracic vertebrae.One case showcased slight-hypo perfusion of the left parietal dura in arterial spin labeling. Conclusions RDD lesion usually appears as iso,slight hypo and slight hyper-intense signals on T2 weighted image and presents intensively homogeneous enhancement in contrast-enhanced MRI.The disease may involve the adjacent bone and the lesion shows slight hypo-perfusion on perfusion images.The MRI manifestations of RDD are characteristic,which are helpful for preoperative diagnosis and evaluation of RDD.


Asunto(s)
Histiocitosis Sinusal , Sistema Nervioso Central/patología , Femenino , Cabeza , Histiocitosis Sinusal/diagnóstico por imagen , Histiocitosis Sinusal/patología , Humanos , Imagen por Resonancia Magnética/métodos , Masculino , Estudios Retrospectivos
19.
Nat Neurosci ; 25(5): 532-534, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35501381
20.
Adv Exp Med Biol ; 1364: 411-422, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35508886

RESUMEN

Skull bone is the main obstacle for transcranial ultrasound therapy and imaging applications. Most efforts in characterizing ultrasonic properties of the skull have been limited to a narrow frequency range and normal incidence. On the other hand, acoustic guided waves in plates have been used in non-destructive evaluation of materials and also to assess the strength of long bones. Recent work has likewise revealed the existence of skull-guided waves (SGWs) in mice and humans when performing measurements over a broad range of frequencies and incidence angles. Here we provide an overview on the recent progress in our understanding on the propagation of SGWs, describe the measurement techniques used to detect SGWs, the experimental observations, and the accompanying modeling efforts. Finally, the outstanding challenges to harness SGWs in applications such as transcranial therapy, imaging, and cranial bone assessment are discussed.


Asunto(s)
Cráneo , Terapia por Ultrasonido , Animales , Cabeza , Ratones , Cráneo/diagnóstico por imagen , Sonido
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