Human skull poses a significant barrier for the propagation of ultrasound waves. Development of methods enabling more efficient ultrasound transmission into and from the brain is therefore critical for the advancement of ultrasound-mediated transcranial imaging or actuation techniques. We report on the first observation of guided acoustic waves in the near field of an ex vivo human skull specimen in the frequency range between 0.2 and 1.5MHz. In contrast to what was previously observed for guided wave propagation in thin rodent skulls, the guided wave observed in a higher-frequency regime corresponds to a quasi-Rayleigh wave, confined mostly to the cortical bone layer. The newly discovered near-field properties of the human skull are expected to facilitate the development of more efficient diagnostic and therapeutic techniques based on transcranial ultrasound.
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http://dx.doi.org/10.1016/j.ultrasmedbio.2018.05.019 | DOI Listing |
Am J Case Rep
January 2025
Department of Neonatology, The Fifth Affiliated Hospital of Zunyi Medical University, Zhuhai, Guangdong, China.
BACKGROUND Cleidocranial dysplasia (CCD) is a rare (1: 1 000 000) autosomal dominant congenital skeletal dysplasia characterized by widely patent calvarial sutures, clavicular hypoplasia, supernumerary teeth, and short stature. Only a minority of the cases are diagnosed early after birth. We present another case of proven CCD presenting with typical neonatal phenotype to promote awareness of this rare disorder.
View Article and Find Full Text PDFPituitary
January 2025
Department of Neurosurgery, Mayo Clinic, Jacksonville, FL, USA.
Purpose: Pituitary adenomas, despite their histologically benign nature, can severely impact patients' quality of life due to hormone hypersecretion. Invasion of the medial wall of the cavernous sinus (MWCS) by these tumors complicates surgical outcomes, lowering biochemical remission rates and increasing recurrence. This study aims to share our institutional experience with the selective resection of the MWCS in endoscopic pituitary surgery.
View Article and Find Full Text PDFAm J Orthod Dentofacial Orthop
February 2025
Department of Orthodontics, Faculty of Dentistry, Çanakkale Onsekiz Mart University, Çanakkale, Turkey.
Introduction: This study aimed to assess the precision of an open-source, clinician-trained, and user-friendly convolutional neural network-based model for automatically segmenting the mandible.
Methods: A total of 55 cone-beam computed tomography scans that met the inclusion criteria were collected and divided into test and training groups. The MONAI (Medical Open Network for Artificial Intelligence) Label active learning tool extension was used to train the automatic model.
J Cereb Blood Flow Metab
January 2025
KG Jebsen Centre for Brain Fluid Research, University of Oslo, Oslo, Norway.
A potential two-way passage of cells and substances between the brain and skull bone marrow may open for new insights into neurological disease. The arachnoid membrane was traditionally considered to restrict cells and larger molecules in CSF from entering the dura and bone marrow directly. However, new data on exchange between brain and skull bone marrow have recently emerged.
View Article and Find Full Text PDFClin Oral Investig
January 2025
Department of Restorative Dentistry, Dental Materials, and Endodontics, Bauru School of Dentistry, University of São Paulo, Rua Siqueira Campos, 180, Centro, Vitória da Conquista, Bauru, São Paulo, BA, ZIP: 45.000-455, Brazil.
Objective: This study investigated the associations among endodontic instruments, ultrasonic tips and various final irrigation protocols for removing intracanal and intratubular biofilms in long oval canals.
Methodology: One hundred mandibular premolars inoculated with Enterococcus faecalis were divided into two groups: the control group (CG: n = 10), which received no treatment; and the test groups (n = 30), which included saline (SS), sodium hypochlorite (2.5% NaOCl) and chlorhexidine (2% CHX).
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