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Anatomical segmentation

Thomas Coquet, Michel Lefranc, Louis Chenin, Pascal Foulon, Éric Havet, Johann Peltier
In this anatomy report, we describe the first case of abducens nerve duplication limited to the sphenopetroclival venous gulf and the cavernous sinus. The objective point of division of the two duplicated roots was localized at the gulfar face of the dural porus, just distal to the unique cisternal trunk of the abducens nerve, as it pierced the petroclival dural mater. In the gulfar segment, both roots traveled through a variant of Dorello's canal called the "petrosphenoidal canal" and remained separated through the posterior half of the cavernous sinus...
March 15, 2018: Surgical and Radiologic Anatomy: SRA
Ruobing Huang, Ana Namburete, Alison Noble
We present a general framework for automatic segmentation of fetal brain structures in ultrasound images inspired by recent advances in machine learning. The approach is based on a region descriptor that characterizes the shape and local intensity context of different neurological structures without explicit models. To validate our framework, we present experiments to segment two fetal brain structures of clinical importance that have quite different ultrasonic appearances-the corpus callosum (CC) and the choroid plexus (CP)...
January 2018: Journal of Medical Imaging
Luzia Diegues Silva, Albert Santos, Luciene Barbosa de Sousa, Norma Allemann, Lauro Augusto de Oliveira
PURPOSE: To report the results of high-resolution anterior segment optical coherence tomography of patients implanted with a type 1 Boston keratoprosthesis (KPro). METHODS: The retrospective study cohort included 11 eyes of 11 patients (average age, 58.4 years; range, 34-83 years). All subjects underwent anterior segment optical coherence tomography at a single posteoperative time point. The main outcome measures were retro-backplate and retro-optic membrane formation, thinning and gap formation of the corneal carrier graft (melting), and degree of angle closure...
January 2018: Arquivos Brasileiros de Oftalmologia
Maxime M Vroegindewey, Anne-Sophie Schuurman, Isabella Kardys, Sharda S Anroedh, Rohit M Oemrawsingh, Jurgen Ligthart, Hector M Garcia-Garcia, Robert-Jan M van Geuns, Evelyn Regar, Nicolas M Van Mieghem, Patrick W Serruys, Eric Boersma, Martijn Akkerhuis
AIMS: To examine the relationship between the anatomical SYNTAX score (SXscore), derived from all three coronary arteries, and coronary wall pathology measured by radiofrequency-intravascular ultrasound (RF-IVUS) and near-infrared spectroscopy (NIRS) in a single non-culprit segment. METHODS AND RESULTS: In referred for coronary angiography (N=88) or PCI (N=592) for stable angina or acute coronary syndrome, the SYNTAX score calculator ( was used to determine SXscore before PCI, if applicable...
March 13, 2018: EuroIntervention
Feng Zhao, Matthew Kirby, Anuradha Roy, Yizhong Hu, X Edward Guo, Xiaodu Wang
Understanding the relationship between the microstructure and mechanical function of trabecular bone is critical for prediction and prevention of bone fragility fractures. However, a detailed understanding of the structural design of trabecular microarchitecture is still missing. This study hypothesized that there exists a commonality in the underlying probabilistic distributions of microstructural features of trabecular bones, whereas the microstructural differences among individuals are primarily describe by a set of scalar parameters...
March 10, 2018: Bone
Jarrod O Drew, Mark R Glyde, Giselle L Hosgood, Alex J Hayes
OBJECTIVE:  To evaluate the effect of tibial plateau levelling osteotomy on stifle extensor mechanism load in an ex vivo cruciate-intact canine cadaveric model. STUDY DESIGN:   Ex vivo mechanical testing study. ANIMALS:  Cadaveric canine pelvic limbs ( n  = 6). MATERIALS AND METHODS:  A 21-mm tibial radial osteotomy was performed on pelvic limbs ( n  = 6) prior to being mounted into a load-bearing limb press...
February 2018: Veterinary and Comparative Orthopaedics and Traumatology: V.C.O.T
Maarten Hp Kole, Romain Brette
The axon initial segment (AIS) is a unique domain of the proximal axon serving critical electrical and structural roles including the initiation of action potentials and maintenance of cellular polarity. Recent experimental and theoretical advances demonstrate that the anatomical site for initiation is remarkably diverse. The AIS location varies not only axially, along the axon, but axons also emerge variably from either the soma or proximal dendrites. Here, we review the evidence that the diversity of AIS and axon location has a substantial impact on the electrical properties and speculate that the anatomical heterogeneity of axon locations expands synaptic integration within cell types and improves information processing in neural circuits...
March 10, 2018: Current Opinion in Neurobiology
Lina Xu, Giles Tetteh, Jana Lipkova, Yu Zhao, Hongwei Li, Patrick Christ, Marie Piraud, Andreas Buck, Kuangyu Shi, Bjoern H Menze
The identification of bone lesions is crucial in the diagnostic assessment of multiple myeloma (MM).68 Ga-Pentixafor PET/CT can capture the abnormal molecular expression of CXCR-4 in addition to anatomical changes. However, whole-body detection of dozens of lesions on hybrid imaging is tedious and error prone. It is even more difficult to identify lesions with a large heterogeneity. This study employed deep learning methods to automatically combine characteristics of PET and CT for whole-body MM bone lesion detection in a 3D manner...
2018: Contrast Media & Molecular Imaging
Quinn A Boser, Aïda M Valevicius, Ewen B Lavoie, Craig S Chapman, Patrick M Pilarski, Jacqueline S Hebert, Albert H Vette
Quantifying angular joint kinematics of the upper body is a useful method for assessing upper limb function. Joint angles are commonly obtained via motion capture, tracking markers placed on anatomical landmarks. This method is associated with limitations including administrative burden, soft tissue artifacts, and intra- and inter-tester variability. An alternative method involves the tracking of rigid marker clusters affixed to body segments, calibrated relative to anatomical landmarks or known joint angles...
February 27, 2018: Journal of Biomechanics
Hideki Sudo, Yuichiro Abe, Terufumi Kokabu, Kei Kuroki, Akira Iwata, Norimasa Iwasaki
STUDY DESIGN: Prospective, non-randomized study. OBJECTIVE: To assess surgical outcomes of multilevel facetectomy and rod curvature with simultaneous double-rod rotation technique for anatomical spinal reconstruction in thoracic adolescent idiopathic scoliosis (AIS). SUMMARY OF BACKGROUND DATA: Although some surgical techniques maintain or restore thoracic kyphosis (TK), next-generation strategies for thoracic AIS should include corrections in three anatomical planes...
March 9, 2018: Spine
Juan Sanchis, Albert Ariza-Solé, Emad Abu-Assi, Oriol Alegre, Fernando Alfonso, José Antonio Barrabés, José Antonio Baz, Antonio Carol, Pablo Díez Villanueva, Bruno García Del Blanco, Jaime Elízaga, Eduard Fernandez, Abel García Del Egido, Joan García Picard, Iván Gómez Blázquez, Joan Antoni Gómez Hospital, Rosana Hernández-Antolín, Cinta Llibre, Francisco Marín, David Martí Sánchez, Roberto Martín, Manuel Martínez Sellés, Gema Miñana, María José Morales Gallardo, Julio Núñez, Armando Pérez de Prado, Eduardo Pinar, Marcelo Sanmartín, Alessandro Sionis, Adolfo Villa, Jaume Marrugat, Héctor Bueno
INTRODUCTION AND OBJECTIVES: Although clinical guidelines recommend invasive management in non-ST-segment elevation myocardial infarction (NSTEMI), this strategy is underused in frail elderly patients in the real world. Furthermore, these patients are underrepresented in clinical trials and therefore the evidence is scarce. Our hypothesis is that an invasive strategy will improve prognosis in elderly frail patients with NSTEMI. METHODS: This will be a prospective, multicenter, randomized trial, in which the conservative and invasive strategies will be compared in patients meeting all of the following inclusion criteria: NSTEMI diagnosis, age ≥ 70 years, and frailty defined by a category ≥ 4 in the Clinical Frailty Scale...
March 7, 2018: Revista Española de Cardiología
Heesun Lee, Yeonyee E Yoon, Wonjae Lee, Hong-Mi Choi, Jun-Bean Park, Hack-Lyoung Kim, Hyo Eun Park, Seung-Pyo Lee, Hyung-Kwan Kim, Su-Yeon Choi, Yong-Jin Kim, Goo-Yeong Cho, Joo-Hee Zo, Dae-Won Sohn
BACKGROUND: While coronary computed tomography angiography (CCTA) provides comprehensive anatomic evaluation of coronary artery disease (CAD) with prognostic implications, clinically, the focus is usually placed on presence or absence of functionally significant CAD. Herein, we aimed to suggest a new risk stratification strategy using CCTA in patients with anatomic CAD but without myocardial ischemia on single-photon emission computed tomography (SPECT). METHODS: Consecutive patients (n=798) with CAD on CCTA who underwent SPECT for evaluation of myocardial ischemia were retrospectively evaluated...
March 7, 2018: Journal of Cardiology
Qing Huang, Hui Ding, Xiaodong Wang, Guangzhi Wang
PURPOSE: Liver segmentation from CT images is a fundamental step in trajectory planning for computer-assisted interventional surgery. In this paper, we present a fully automatic procedure using modified graph cuts and feature detection for accurate and fast liver segmentation. METHODS: The initial slice and seeds of graph cuts are automatically determined using an intensity-based method with prior position information. A contrast term based on the similarities and differences of local organs across multi-slices is proposed to enhance the weak boundaries of soft organs and to prevent over-segmentation...
February 22, 2018: Computers in Biology and Medicine
Hester F Shieh, C Jason Smithers, Thomas E Hamilton, David Zurakowski, Gary A Visner, Michael A Manfredi, Russell W Jennings, Christopher W Baird
OBJECTIVE: Posterior descending aortopexy can relieve posterior intrusion of the left mainstem bronchus that may limit the effectiveness of posterior tracheobronchopexy. We review outcomes of patients undergoing both descending aortopexy and posterior tracheopexy for severe tracheobronchomalacia with posterior intrusion and left mainstem compression to determine if there were resolution of clinical symptoms and bronchoscopic evidence of improvement in airway collapse. METHODS: All patients who underwent both descending aortopexy and posterior tracheopexy from October 2012 to October 2016 were retrospectively reviewed...
March 7, 2018: Seminars in Thoracic and Cardiovascular Surgery
Nina Alexeeva, Yuta Tamberg, Natalia Shunatova
Sea spiders form a small, enigmatic group of recent chelicerates, with an unusual bodyplan, oligosegmented larvae and a postembryonic development that is punctuated by many moults. To date, only a few papers examined the anatomical and ultrastructural modifications of the larvae and various instars. Here we traced both internal and external events of the whole postembryonic development in Nymphon brevirostre HODGE 1863 using histology, SEM, TEM and confocal microscopy. During postembryonic development, larvae of this species undergo massive reorganization: spinning apparatus and chelar glands disappear; larval legs redifferentiate; three new segments and abdomen are formed with their corresponding internal organs and appendages; circulatory and reproductive systems develop anew and the digestive and the nervous systems change dramatically...
March 7, 2018: Arthropod Structure & Development
Richard Boyle, Reza Ehsanian, Alireza Mofrad, Yekaterina Popova, Joseph Varelas
The utricle provides the vestibular reflex pathways with the sensory codes of inertial acceleration of self motion and head orientation with respect to gravity to control balance and equilibrium. Here we present an anatomical description of this structure in the adult oyster toadfish, and establish a morphological basis for interpretation of subsequent functional studies. Light, scanning and transmission electron microscopy techniques were applied to visualize the sensory epithelium at varying levels of detail, its neural innervation and its synaptic organization...
March 10, 2018: Journal of Comparative Neurology
A Burssens, J Peeters, M Peiffer, R Marien, T Lenaerts, G Vandeputte, J Victor
PURPOSE: The exact radiographic assessment of the hindfoot alignment remains challenging. This is reflected in the different measurement methods available. Weightbearing CT (WBCT) has been demonstrated to be more accurate in hindfoot measurements. However, current measurements are still performed in 2D. This study wants to assess the use of computed methods to convert the former uniplanar hindfoot measurements obtained after WBCT towards a 3D setting. METHODS: Forty-eight patients, mean age of 39...
March 9, 2018: International Journal of Computer Assisted Radiology and Surgery
Jesper D Nielsen, Kristoffer H Madsen, Oula Puonti, Hartwig R Siebner, Christian Bauer, Camilla Gøbel Madsen, Guilherme B Saturnino, Axel Thielscher
Anatomically realistic volume conductor models of the human head are important for accurate forward modeling of the electric field during transcranial brain stimulation (TBS), electro- (EEG) and magnetoencephalography (MEG). In particular, the skull compartment exerts a strong influence on the field distribution due to its low conductivity, suggesting the need to represent its geometry accurately. However, automatic skull reconstruction from structural magnetic resonance (MR) images is difficult, as compact bone has a very low signal in magnetic resonance imaging (MRI)...
March 5, 2018: NeuroImage
Neil P Reddy, Sung Wan Ham, Fred A Weaver, Vincent L Rowe, Kenneth R Ziegler, Sukgu M Han
Endovascular aneurysm repair has become the first-line treatment modality for infrarenal aortic aneurysms. However, obtaining successful long-term results frequently require re-interventions. Particularly, delayed type 1a endoleaks pose a challenging problem, as they are often associated with proximal extension of the aneurysmal process to juxta or para-renal aortic segments. We describe two remedial techniques to repair delayed type 1a endoleak by extending the seal zone to the suprarenal aorta, while incorporating the renal arteries...
March 5, 2018: Annals of Vascular Surgery
Evan M Masutani, Francisco Contijoch, Espoir Kyubwa, Joseph Cheng, Marcus T Alley, Shreyas Vasanawala, Albert Hsiao
PURPOSE: To develop a rapid segmentation-free method to visualize and compute wall shear stress (WSS) throughout the aorta using 4D Flow MRI data. WSS is the drag force-per-area the vessel endothelium exerts on luminal blood; abnormal levels of WSS are associated with cardiovascular pathologies. Previous methods for computing WSS are bottlenecked by labor-intensive manual segmentation of vessel boundaries. A rapid automated segmentation-free method for computing WSS is presented. THEORY AND METHODS: Shear stress is the dot-product of the viscous stress tensor and the inward normal vector...
March 7, 2018: Magnetic Resonance in Medicine: Official Journal of the Society of Magnetic Resonance in Medicine
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