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Sample records for growing skull fracture

  1. [Growing skull fracture in childhood. Presentation of 12 cases].

    PubMed

    Mierez, R; Guillén, A; Brell, M; Cardona, E; Claramunt, E; Costa, J M

    2003-06-01

    Growing skull fractures (GSF) are rare complications of head injury (HI) in childhood. This entity consists of a skull fracture with an underlying dural tear that courses with a progressive enlargement of the fracture to produce a cranial defect. The pathophysiology and some aspects of its management are still controversial. In this review we present 12 patients diagnosedd and treated for a GSF at our institution between 1980 and 2002. 11 patients were under the age of 3 years and one patient was 5 years old at the moment of HI. The most common cause of injury was a fall from height. In the initial plain x-rayfilms, 11 patients showed a diastatic skull fracture and one patient only had a linear fracture. At this time, CT scan showed cortical contussion underlying the fracture in every case. The mean time between injury and presentation of GSF was 11.6 weeks. Diagnosis was made by palpation of the cranial defect and confirmed with skull x-rayfilms. The most frecuent location of GSF was in the parietal region. Associated lesions like hydrocephalus, encephalomalacia, lepto-menigeal cysts, brain tissue herniation and ipsilateral ventricular dilatation, were found in the preoperative CT or MRI. All patients underwent a dural repair with pericranium or fascia lata. The cranial defect was covered with local calvarial bone fragments in every case. Only one patient needed a cranioplasty with titanium mesh. Every child with a skull fracture must be followed until the fracture heals. Patients under the age of 3 years with a diastatic fracture and a dural tear, demostrated by TC or MRI, are more prone to develop GSF. In these cases, early repair must be adviced in order to prevent progressive brain damage.

  2. Remote intracranial hemorrhage following surgery for giant orbitofrontal growing skull fracture: A lesson learnt

    PubMed Central

    Baldawa, Sachin

    2016-01-01

    Growing skull fracture is an extremely rare complication of pediatric head injury, especially in infants. Repair of the dural tear early in the course of development of growing skull fracture has been suggested for a better outcome. Surgical repair of large, tense growing skull fractures, especially those in the communication of the ventricles can lead to potentially life-threatening complications. The author reports a rare case of remote intracranial hemorrhage following surgery for large, tense growing skull fracture in a 12-year-old girl and discusses the likely pathogenesis and possible ways to avoid this life-threatening complication. PMID:27606019

  3. Remote intracranial hemorrhage following surgery for giant orbitofrontal growing skull fracture: A lesson learnt.

    PubMed

    Baldawa, Sachin

    2016-01-01

    Growing skull fracture is an extremely rare complication of pediatric head injury, especially in infants. Repair of the dural tear early in the course of development of growing skull fracture has been suggested for a better outcome. Surgical repair of large, tense growing skull fractures, especially those in the communication of the ventricles can lead to potentially life-threatening complications. The author reports a rare case of remote intracranial hemorrhage following surgery for large, tense growing skull fracture in a 12-year-old girl and discusses the likely pathogenesis and possible ways to avoid this life-threatening complication. PMID:27606019

  4. John Howship (1781-1841) and growing skull fracture: historical perspective.

    PubMed

    Bir, Shyamal C; Kalakoti, Piyush; Notarianni, Christina; Nanda, Anil

    2015-10-01

    In the late 18th and early 19th centuries, Dr. John Howship, a pioneering British surgeon, described the clinical features and pathophysiology of various surgical disorders of the human body. His critical contributions to pediatric neurosurgery came in 1816 when he first described the features of an important childhood condition following head trauma, what he referred to as parietal bone absorption. This condition as depicted by Dr. Howship was soon to be christened by later scholars as traumatic cephalhydrocele, traumatic meningocele, leptomeningeal cyst, meningocele spuria, fibrosing osteitis, cerebrocranial erosion, and growing skull fracture. Nevertheless, the basic features of the condition as observed by Dr. Howship were virtually identical to the characteristics of the above-mentioned disorders. This article describes the life and accomplishments of Dr. Howship and his contributions to the current understanding of growing skull fracture.

  5. Infant skull fracture (image)

    MedlinePlus

    Skull fractures may occur with head injuries. Although the skull is both tough and resilient and provides excellent ... or blow can result in fracture of the skull and may be accompanied by injury to the ...

  6. Anisotropic composite human skull model and skull fracture validation against temporo-parietal skull fracture.

    PubMed

    Sahoo, Debasis; Deck, Caroline; Yoganandan, Narayan; Willinger, Rémy

    2013-12-01

    A composite material model for skull, taking into account damage is implemented in the Strasbourg University finite element head model (SUFEHM) in order to enhance the existing skull mechanical constitutive law. The skull behavior is validated in terms of fracture patterns and contact forces by reconstructing 15 experimental cases. The new SUFEHM skull model is capable of reproducing skull fracture precisely. The composite skull model is validated not only for maximum forces, but also for lateral impact against actual force time curves from PMHS for the first time. Skull strain energy is found to be a pertinent parameter to predict the skull fracture and based on statistical (binary logistical regression) analysis it is observed that 50% risk of skull fracture occurred at skull strain energy of 544.0mJ.

  7. Biomechanics of frontal skull fracture.

    PubMed

    Delye, Hans; Verschueren, Peter; Depreitere, Bart; Verpoest, Ignaas; Berckmans, Daniel; Vander Sloten, Jos; Van Der Perre, Georges; Goffin, Jan

    2007-10-01

    The purpose of the present study was to investigate whether an energy failure level applies to the skull fracture mechanics in unembalmed post-mortem human heads under dynamic frontal loading conditions. A double-pendulum model was used to conduct frontal impact tests on specimens from 18 unembalmed post-mortem human subjects. The specimens were isolated at the occipital condyle level, and pre-test computed tomography images were obtained. The specimens were rigidly attached to an aluminum pendulum in an upside down position and obtained a single degree of freedom, allowing motion in the plane of impact. A steel pendulum delivered the impact and was fitted with a flat-surfaced, cylindrical aluminum impactor, which distributed the load to a force sensor. The relative displacement between the two pendulums was used as a measure for the deformation of the specimen in the plane of impact. Three impact velocity conditions were created: low (3.60+/-0.23 m/sec), intermediate (5.21+/-0.04 m/sec), and high (6.95+/-0.04 m/sec) velocity. Computed tomography and dissection techniques were used to detect pathology. If no fracture was detected, repeated tests on the same specimen were performed with higher impact energy until fracture occurred. Peak force, displacement and energy variables were used to describe the biomechanics. Our data suggests the existence of an energy failure level in the range of 22-24 J for dynamic frontal loading of an intact unembalmed head, allowed to move with one degree of freedom. Further experiments, however, are necessary to confirm that this is a definitive energy criterion for skull fracture following impact. PMID:17970621

  8. Automatic analysis of a skull fracture based on image content

    NASA Astrophysics Data System (ADS)

    Shao, Hong; Zhao, Hong

    2003-09-01

    Automatic analysis based on image content is a hotspot with bright future of medical image diagnosis technology research. Analysis of the fracture of skull can help doctors diagnose. In this paper, a new approach is proposed to automatically detect the fracture of skull based on CT image content. First region growing method, whose seeds and growing rules are chosen by k-means clustering dynamically, is applied for image automatic segmentation. The segmented region boundary is found by boundary tracing. Then the shape of the boundary is analyzed, and the circularity measure is taken as description parameter. At last the rules for computer automatic diagnosis of the fracture of the skull are reasoned by entropy function. This method is used to analyze the images from the third ventricles below layer to cerebral cortex top layer. Experimental result shows that the recognition rate is 100% for the 100 images, which are chosen from medical image database randomly and are not included in the training examples. This method integrates color and shape feature, and isn't affected by image size and position. This research achieves high recognition rate and sets a basis for automatic analysis of brain image.

  9. The significance of incomplete skull fracture in the birth injury.

    PubMed

    Oh, Chang Keun; Yoon, Soo Han

    2010-05-01

    Vaginal delivery is accomplished by the force of the labor overcoming the resistance forces of birth canal. During this process, the fetal head passes through the birth canal and the skull receives pressure on the lateral aspect, resulting in molding, the convex shaping of the cranium. Also, the infant's skull is compressed by the mother's pelvic bony structures. These forces may lead to skull fractures and brain injuries. The hypothesis by the authors is that many skull fractures of the newborn present as incomplete fractures. The bony skull of the newborn is histologically primary bone tissue and which is incomplete in its ossification process. During birth the pressure forces upon the newborn's skull is gradual in one direction, rather than a sudden impact, and therefore it is thought that the skull fracture would be an incomplete fracture. However, it is very hard to ascertain the presence of incomplete fractures especially in incompletely ossified skulls with plain X-ray studies, and therefore it is possible that the real incidence of skull fractures in the newborn are higher than reported in the current and past literature. It is also probable that the external forces upon the skull that are sufficient to cause skull fractures, would also lead to significant brain injury more frequently than actually observed, and subsequently contribute to development of many brain disease later in children. The authors of this study propose that very close examination should be conducted to find incomplete fracture, and increased efforts should be made to establish the presence of possible accompanied brain injuries in babies with incomplete skull fracture. The definitive diagnosis and treatment, as well as close follow up of patients with brain injury will assist the clinician in determining the causes of neurological diseases especially in those with previously unknown etiologies, which may be due to birth injuries. Assistance may be also afforded in the early treatment

  10. A new test set-up for skull fracture characterisation.

    PubMed

    Verschueren, P; Delye, H; Depreitere, B; Van Lierde, C; Haex, B; Berckmans, D; Verpoest, I; Goffin, J; Vander Sloten, J; Van der Perre, G

    2007-01-01

    Skull fracture is a frequently observed type of severe head injury. Historically, a variety of impact test set-ups and techniques have been used for investigating skull fracture. The most frequently used are the free-fall technique, the guided fall or drop tower set-up and the piston-driven impactor set-up. This document proposes a new type of set-up for cadaver head impact testing which combines the strengths of the most frequently used techniques and devices. The set-up consists of two pendulums, which allow for a 1 degree of freedom rotational motion. The first pendulum is the impactor and is used to strike the blow. The head is attached to the second pendulum using a polyester resin. Local skull deformation and impact force are measured with a sample frequency of 65 kHz. From these data, absorbed energy until skull fracture is calculated. A set-up evaluation consisting of 14 frontal skull and head impact tests shows an accurate measurement of both force and local skull deformation until fracture of the skull. Simplified mechanical models are used to analyse the different impacting techniques from literature as well as the new proposed set-up. It is concluded that the proposed test set-up is able to accurately calculate the energy absorbed by the skull until fracture with an uncertainty interval of 10%. Second, it is concluded that skull fracture caused by blunt impact occurs before any significant motion of the head. The two-pendulum set-up is the first head impact device to allow a well-controlled measurement environment without altering the skull stress distribution.

  11. [Recurring post-traumatic growing skull fracture].

    PubMed

    San Martín-García, Isabel; Aguilera-Albesa, Sergio; Zazpe-Cenoz, Idoya; Yoldi-Petri, M Eugenia

    2015-04-16

    Introduccion. La fractura craneal evolutiva, tambien llamada absorcion osea postraumatica o quiste leptomeningeo, es una rara complicacion de los traumatismos craneoencefalicos y ocurre de forma casi exclusiva en ninos menores de 3 anos. Caso clinico. Nino de 6 meses que presentaba, dos meses despues de un traumatismo craneal aparentemente banal, persistencia de cefalohematoma temporooccipital izquierdo sin otros signos. El estudio de ecografia transfontanelar revelo un defecto oseo con herniacion cerebral, y la tomografia computarizada y la resonancia magnetica confirmaron, ademas, una fractura evolutiva. Se realizo reseccion del quiste encefalomeningeo, cierre dural y reparacion del defecto oseo con placas y material de lactato. Tres meses despues de la intervencion, presentaba persistencia de coleccion liquida y se confirmo recidiva de la fractura evolutiva. Tras la reintervencion, se coloco casco ortesico para evitar nuevas recidivas. Un ano despues del traumatismo, el paciente continua asintomatico. Conclusiones. Todo nino menor de 3 anos con cefalohematoma postraumatico deberia ser revisado de forma periodica hasta comprobar la resolucion de la coleccion, en particular si presenta fractura craneal. La presencia de un cefalohematoma persistente mas de dos semanas despues de un traumatismo craneoencefalico debe hacernos sospechar un proceso de fractura creciente, y son necesarias la reparacion de la duramadre y una craneoplastia para su tratamiento. La colocacion de material reabsorbible permite su remodelacion con el crecimiento craneal del paciente, pero su fragilidad conlleva riesgo de recidiva. La colocacion de un casco ortesico tras la intervencion podria prevenir complicaciones.

  12. Harvey Cushing's Early Operative Treatment of Skull Base Fractures.

    PubMed

    Pendleton, Courtney; Raza, Shaan M; Gallia, Gary L; Quinones-Hinojosa, Alfredo

    2014-02-01

    Objectives To review Dr. Harvey Cushing's early surgical cases at the Johns Hopkins Hospital, revealing details of his operative approaches to fractures of the skull base. Design Following institutional review board approval and through the courtesy of the Alan Mason Chesney Archives, we reviewed the Johns Hopkins Hospital surgical files. Setting The Johns Hopkins Hospital, 1896 to 1912. Participants A total of 24 patients underwent operative treatment for suspected fractures of the skull base. Main Outcome Measures The main outcome measure was operative approach, postoperative mortality, and condition recorded at the time of discharge. Results Overall, 23 patients underwent operative treatment for suspected skull base fractures. The mechanisms of injury were known for 22 patients and included work-related injuries (41%), falls (23%), vehicle injuries (32%), and other trauma (5%). One patient had no mechanism of injury specified in the file. The outcome at the time of discharge from the hospital was "well" or "improved" in 12 patients (52%). The remaining 11 patients died during their admission. Conclusions Although Cushing's experience with selected skull base pathology has been previously reported, the breadth of his contributions to operative approaches to the skull base has been neglected. PMID:24498586

  13. Cerebral Venous Air Embolism due to a Hidden Skull Fracture Secondary to Head Trauma

    PubMed Central

    Hosaka, Ai; Yamaguchi, Tetsuto; Yamamoto, Fumiko; Shibagaki, Yasuro

    2015-01-01

    Cerebral venous air embolism is sometimes caused by head trauma. One of the paths of air entry is considered a skull fracture. We report a case of cerebral venous air embolism following head trauma. The patient was a 55-year-old man who fell and hit his head. A head computed tomography (CT) scan showed the air in the superior sagittal sinus; however, no skull fractures were detected. Follow-up CT revealed a fracture line in the right temporal bone. Cerebral venous air embolism following head trauma might have occult skull fractures even if CT could not show the skull fractures. PMID:26693366

  14. Cerebral Venous Air Embolism due to a Hidden Skull Fracture Secondary to Head Trauma.

    PubMed

    Hosaka, Ai; Yamaguchi, Tetsuto; Yamamoto, Fumiko; Shibagaki, Yasuro

    2015-01-01

    Cerebral venous air embolism is sometimes caused by head trauma. One of the paths of air entry is considered a skull fracture. We report a case of cerebral venous air embolism following head trauma. The patient was a 55-year-old man who fell and hit his head. A head computed tomography (CT) scan showed the air in the superior sagittal sinus; however, no skull fractures were detected. Follow-up CT revealed a fracture line in the right temporal bone. Cerebral venous air embolism following head trauma might have occult skull fractures even if CT could not show the skull fractures. PMID:26693366

  15. Biomechanical analysis of skull fractures after uncontrolled hanging release.

    PubMed

    Thollon, Lionel; Llari, Maxime; André, Lucile; Adalian, Pascal; Leonetti, Georges; Piercecchi-Marti, Marie-Dominique

    2013-12-10

    In forensic research, biomechanical analyses of falls are widely reported. However, no study on falls consecutive to uncontrolled hanging release, when a hanging body is cut down, has ever been published. In such cases, the presence of cranial trauma can raise interpretation issues, and there may be doubt as to whether the fall was an accident or a crime disguised as suicide. The problem remains as to whether or not a fall after a free hanging release can lead to a skull fracture. To address this question, numerical simulations, post-mortem human subject tests and parametric studies were performed. We first recreated the kinematics and velocity of this atypical fall with post-mortem human subject tests and multibody simulations. We then tested the influence of biological variability on fracture production using a finite element model of the head. Our results show that fall severity depends largely on the direction of the fall. The risk of fracture is highest in the occipital region and with a backward fall. Our study also highlights the frequent occurrence of lower limb trauma in a free hanging release. Most importantly, we show that a fracture is produced in only 3.4% of falls that occur in a 10-90 cm height range. The overall findings of this study provide tools for pathologists and magistrates to decide on the most likely scenario and to justify further forensic investigations if required. PMID:24314523

  16. Biomechanical analysis of skull fractures after uncontrolled hanging release.

    PubMed

    Thollon, Lionel; Llari, Maxime; André, Lucile; Adalian, Pascal; Leonetti, Georges; Piercecchi-Marti, Marie-Dominique

    2013-12-10

    In forensic research, biomechanical analyses of falls are widely reported. However, no study on falls consecutive to uncontrolled hanging release, when a hanging body is cut down, has ever been published. In such cases, the presence of cranial trauma can raise interpretation issues, and there may be doubt as to whether the fall was an accident or a crime disguised as suicide. The problem remains as to whether or not a fall after a free hanging release can lead to a skull fracture. To address this question, numerical simulations, post-mortem human subject tests and parametric studies were performed. We first recreated the kinematics and velocity of this atypical fall with post-mortem human subject tests and multibody simulations. We then tested the influence of biological variability on fracture production using a finite element model of the head. Our results show that fall severity depends largely on the direction of the fall. The risk of fracture is highest in the occipital region and with a backward fall. Our study also highlights the frequent occurrence of lower limb trauma in a free hanging release. Most importantly, we show that a fracture is produced in only 3.4% of falls that occur in a 10-90 cm height range. The overall findings of this study provide tools for pathologists and magistrates to decide on the most likely scenario and to justify further forensic investigations if required.

  17. [A Case of Depressed Skull Fracture Involving only the Inner Table].

    PubMed

    Miyake, Shigeta; Yamamura, Kouji; Abe, Hiroyuki

    2016-07-01

    Depressed skull fracture commonly results from trauma and usually occurs following high-speed impact with a small object. The outer and inner tables of the skull typically break concurrently. We present a case of depressed skull fracture involving only the inner table. The case resulted in a good outcome with only conservative treatment, although the mechanism remained unclear. Fracture models of cadavers have been the main tool for biomechanical investigation, but this classical method cannot accurately measure mechanical factors. We utilized a computer simulation model to assess the human head following skull fracture. This is the first report of an inner table fracture;the fracture mechanism was determined using a simulated computer model. PMID:27384121

  18. [Skull fracture or accessory suture in a child?].

    PubMed

    Burkhard, Katrin; Lange, Lena M; Plenzig, Stefanie; Verhoff, Marcel A; Kölzer, Sarah C

    2016-01-01

    Differentiation between accessory sutures and fractures in the skull of an infant can be difficult. Apart from the regular sutures there is a multitude of variations that may be mistaken for a fracture line. Such variations include for instance the intraparietal suture between the two ossification centers of the parietal bone or the mendosal suture between the supraoccipital and interparietal bone of the occipital squama. The presented case refers to an approximately 20-month-old female child. During autopsy, a discontinuity in the right paramedian posterior cranial fossa parallel to the internal occipital crest with connection to the foramen magnum was observed. The macroscopic findings suggested a fracture line because of its course. However, neither a hemorrhage in the soft tissue nor callus formation was discernible. The discontinuity was preserved with the adjacent parts of the occipital bone for further histological examination. In the report of a cranial CT, which was carried out five days before the child's death, an accessory suture paramedially in the right posterior cranial fossa was described. When the clinical CT records were re-evaluated, a similar discontinuity at the corresponding position on the other side was detected, though of noticeably shorter length. Additionally, the preserved occipital bone fragment including the discontinuity was histologically processed. In the radiological literature, precise (radiological) criteria for differential diagnosis are indicated. A zigzag pattern with sclerotic borders and a bilateral and fairly symmetric occurrence indicate a suture, whereas a sharp lucency with non-sclerotic edges and a unilateral occurrence indicate a fracture. Taking all the findings into account, the depicted discontinuity was regarded as an accessory suture. This case demonstrates that differentiation between a fracture and an accessory suture may be difficult in the autopsy of a child and underlines the importance of a postmortem CT

  19. Fractures of the growing mandible.

    PubMed

    Kushner, George M; Tiwana, Paul S

    2009-03-01

    Oral and maxillofacial surgeons must constantly weigh the risks of surgical intervention for pediatric mandible fractures against the wonderful healing capacity of children. The majority of pediatric mandibular fractures can be managed with closed techniques using short periods of maxillomandibular fixation or training elastics alone. Generally, the use of plate- and screw-type internal fixation is reserved for difficult fractures. This article details general and special considerations for this surgery including: craniofacial growth & development, surgical anatomy, epidemiology evaluation, various fractures, the role rigid internal fixation and the Risdon cable in pediatric maxillofacial trauma. It concludes with suggestions concerning long-term follow-up care in light of the mobility, insurance obstacles, and family dynamics facing the patient population.

  20. Creation of a High-fidelity, Low-cost Pediatric Skull Fracture Ultrasound Phantom.

    PubMed

    Soucy, Zachary P; Mills, Lisa; Rose, John S; Kelley, Kenneth; Ramirez, Francisco; Kuppermann, Nathan

    2015-08-01

    Over the past decade, point-of-care ultrasound has become a common tool used for both procedures and diagnosis. Developing high-fidelity phantoms is critical for training in new and novel point-of-care ultrasound applications. Detecting skull fractures on ultrasound imaging in the younger-than-2-year-old patient is an emerging area of point-of-care ultrasound research. Identifying a skull fracture on ultrasound imaging in this age group requires knowledge of the appearance and location of sutures to distinguish them from fractures. There are currently no commercially available pediatric skull fracture models. We outline a novel approach to building a cost-effective, simple, high-fidelity pediatric skull fracture phantom to meet a unique training requirement.

  1. Fracture pattern interpretation in the skull: differentiating blunt force from ballistics trauma using concentric fractures.

    PubMed

    Hart, Gina O

    2005-11-01

    There have been several anthropological studies on trauma analysis in recent literature, but few studies have focused on the differences between the three mechanisms of trauma (sharp force trauma, blunt force trauma and ballistics trauma). The hypothesis of this study is that blunt force and ballistics fracture patterns in the skull can be differentiated using concentric fractures. Two-hundred and eleven injuries from skulls exhibiting concentric fractures were examined to determine if the mechanism of trauma could be determined by beveling direction. Fractures occurring in buttressed and non-buttressed regions were examined separately. Contingency tables and Pearson's Chi-Square were used to evaluate the relationship between the two variables (the mechanism of trauma and the direction of beveling), while Pearson's r correlation was used to determine the strength of the relationship. Contingency tables and Chi-square tests among the entire sample, the buttressed areas, and the non-buttressed areas led to the null hypothesis (no relationship) to be rejected. Pearson's r correlation indicated that the relationship between the variables studied is greater than chance allocation.

  2. Fracture patterns on the infant porcine skull following severe blunt impact.

    PubMed

    Powell, Brian J; Passalacqua, Nicholas V; Baumer, Timothy G; Fenton, Todd W; Haut, Roger C

    2012-03-01

    The objective of this study was to document patterns of fracture on infant porcine skulls aged 2-28 days (n = 57) because of a single, high energy blunt impact to the parietal bone with rigid (nondeformable) and compliant (deformable) interfaces. Fracture patterns were mapped using Geographic Information System software. For the same generated impact force, the rigid interface produced more fractures than the compliant interface for all ages. This study also showed that this increased level of impact energy versus an earlier study using a lower energy resulted in new sites of fracture initiation and also caused previously defined fractures that propagate into an adjacent bone. Several unique characteristics of bone and diastatic fracture were documented as a function of specimen age, impact energy, and interface. These data describe some baseline characteristics of skull fracture using an animal model that may help guide future studies from forensic case files.

  3. Transfer of children with isolated linear skull fractures: is it worth the cost?

    PubMed

    White, Ian K; Pestereva, Ecaterina; Shaikh, Kashif A; Fulkerson, Daniel H

    2016-05-01

    OBJECTIVE Children with skull fractures are often transferred to hospitals with pediatric neurosurgical capabilities. Historical data suggest that a small percentage of patients with an isolated skull fracture will clinically decline. However, recent papers have suggested that the risk of decline in certain patients is low. There are few data regarding the financial costs associated with transporting patients at low risk for requiring specialty care. In this study, the clinical outcomes and financial costs of transferring of a population of children with isolated skull fractures to a Level 1 pediatric trauma center over a 9-year period were analyzed. METHODS A retrospective review of all children treated for head injury at Riley Hospital for Children (Indianapolis, Indiana) between 2005 and 2013 was performed. Patients with a skull fracture were identified based on ICD-9 codes. Patients with intracranial hematoma, brain parenchymal injury, or multisystem trauma were excluded. Children transferred to Riley Hospital from an outside facility were identified. The clinical and radiographic outcomes were recorded. A cost analysis was performed on patients who were transferred with an isolated, linear, nondisplaced skull fracture. RESULTS Between 2005 and 2013, a total of 619 pediatric patients with isolated skull fractures were transferred. Of these, 438 (70.8%) patients had a linear, nondisplaced skull fracture. Of these 438 patients, 399 (91.1%) were transferred by ambulance and 39 (8.9%) by helicopter. Based on the current ambulance and helicopter fees, a total of $1,834,727 (an average of $4188.90 per patient) was spent on transfer fees alone. No patient required neurosurgical intervention. All patients recovered with symptomatic treatment; no patient suffered late decline or epilepsy. CONCLUSIONS This study found that nearly $2 million was spent solely on transfer fees for 438 pediatric patients with isolated linear skull fractures over a 9-year period. All patients

  4. Delayed Intracerebral Hemorrhage from a Pseudoaneurysm Following a Depressed Skull Fracture

    PubMed Central

    Nazari, Pouya; Wewel, Joshua T.; Dua, Sumeet G.; Chen, Michael

    2016-01-01

    A 26-year-old male presented with delayed intracerebral hemorrhage from a ruptured distal middle cerebral artery pseudoaneurysm that followed a compound depressed skull fracture from years ago. The brain protrusion through the skull defect likely resulted in stretching and subsequent tearing of the arterial wall resulting in the pseudoaneurysm formation. No prior report of such a clinical occurrence exists in the literature. We highlight an unusual but treatable cause for intracerebral hemorrhage following surgery for traumatic brain injury. PMID:26958412

  5. Development of skull fracture criterion based on real-world head trauma simulations using finite element head model.

    PubMed

    Sahoo, Debasis; Deck, Caroline; Yoganandan, Narayan; Willinger, Rémy

    2016-04-01

    The objective of this study was to enhance an existing finite element (FE) head model with composite modeling and a new constitutive law for the skull. The response of the state-of-the-art FE head model was validated in the time domain using data from 15 temporo-parietal impact experiments, conducted with postmortem human surrogates. The new model predicted skull fractures observed in these tests. Further, 70 well-documented head trauma cases were reconstructed. The 15 experiments and 70 real-world head trauma cases were combined to derive skull fracture injury risk curves. The skull internal energy was found to be the best candidate to predict skull failure based on an in depth statistical analysis of different mechanical parameters (force, skull internal energy), head kinematic-based parameter, the head injury criterion (HIC), and skull fracture correlate (SFC). The proposed tolerance limit for 50% risk of skull fracture was associated with 453mJ of internal energy. Statistical analyses were extended for individual impact locations (frontal, occipital and temporo-parietal) and separate injury risk curves were obtained. The 50% risk of skull fracture for each location: frontal: 481mJ, occipital: 457mJ, temporo-parietal: 456mJ of skull internal energy.

  6. Missed clavicle fractures on anterior-posterior views of skull X-rays: a retrospective, observational, and descriptive study

    PubMed Central

    Kim, Jung-Heon; Lee, Jeong-Yong; Cho, Hyung-Rae; Lee, Jong-Seung; Ryu, Jeong-Min

    2015-01-01

    Objective The clavicle is almost always seen in skull X-rays of infants. The objectives of this study were to determine how often the clavicle and clavicle fractures are visible but missed on the skull anterior-posterior view (skull AP) of infants and which factors are associated with missing the diagnosis. Methods We retrospectively studied patients aged 1 year or younger who had a skull AP taken for any injury survey at a single urban, academic hospital between April 1999 and July 2012. Outcomes of interest were the numbers and percentages of visible clavicles; clavicle fractures, including missed ones on skull AP; and the factors associated with missing the diagnosis of a clavicle fracture. Results Both clavicles were visible in 734 patients (89.6%). Of these, 10 patients (1.4%) had confirmed clavicle fractures, and 6 patients (0.8%) had fractures that were missed at presentation. Although we tried to determine the factors that might be associated with missed diagnoses, including age <6 months, male sex, blocking by guardian’s hands, associated skull fractures, and mechanism of injury, none was significantly associated with missed clavicle fractures. Conclusion The clavicles were recognizable on skull X-rays in most cases. Therefore, one should check the clavicles when reading skull X-rays.

  7. Depressed Skull Fractures: A Pattern of Abusive Head Injury in Three Older Children

    ERIC Educational Resources Information Center

    Lee, Anselm C. W.; Ou, Yvonne; Fong, Dawson

    2003-01-01

    Objective: To describe a pattern of abusive head injury in a series of children older than 4 years of age. Methods: A hospital chart review of abused children with skull fractures from 1999 to 2001 was carried out. The clinical features, social background, and subsequent outcome and management are described. Results: An 11-year-old girl and a pair…

  8. An orbital roof and anterior skull base fracture: case report.

    PubMed

    Gennaro, P; Mitro, V; Gabriele, G; Giovannetti, F; Facchini, A

    2012-10-01

    Blow-out fractures usually involve the orbit in the floor or in the medial wall. Anyway, if the roof of the orbit is thin and direct compressive or buckling forces impact the orbit the fracture can involve the upper roof. We describe the case of a blow-out fracture of the orbital roof with enophtalmus and cerebrospinal fluid leak from lacero-contusive subciliar wound

  9. Secondary skull fractures in head wounds inflicted by captive bolt guns: autopsy findings and experimental simulation.

    PubMed

    Perdekamp, Markus Grosse; Kneubuehl, Beat P; Ishikawa, Takaki; Nadjem, Hadi; Kromeier, Jan; Pollak, Stefan; Thierauf, Annette

    2010-11-01

    Apart from one article published by Rabl and Sigrist in 1992 (Rechtsmedizin 2:156-158), there are no further reports on secondary skull fractures in shots from captive bolt guns. Up to now, the pertinent literature places particular emphasis on the absence of indirect lesions away from the impact point, when dealing with the wounding capacity of slaughterer's guns. The recent observation of two suicidal head injuries accompanied by skull fractures far away from the bolt's path gave occasion to experimental studies using simulants (glycerin soap, balls from gelatin) and skull–brain models. As far as ballistic soap was concerned, the dimensions of the bolt's channel were assessed by multi-slice computed tomography before cutting the blocks open. The test shots to gelatin balls and to skull-brain models were documented by means of a high-speed motion camera. As expected, the typical temporary cavity effect of bullets fired from conventional guns could not be observed when captive bolt stunners were discharged. Nevertheless, the visualized transfer of kinetic energy justifies the assumption that the secondary fractures seen in thin parts of the skull were caused by a hydraulic burst effect. PMID:20393855

  10. Secondary skull fractures in head wounds inflicted by captive bolt guns: autopsy findings and experimental simulation.

    PubMed

    Perdekamp, Markus Grosse; Kneubuehl, Beat P; Ishikawa, Takaki; Nadjem, Hadi; Kromeier, Jan; Pollak, Stefan; Thierauf, Annette

    2010-11-01

    Apart from one article published by Rabl and Sigrist in 1992 (Rechtsmedizin 2:156-158), there are no further reports on secondary skull fractures in shots from captive bolt guns. Up to now, the pertinent literature places particular emphasis on the absence of indirect lesions away from the impact point, when dealing with the wounding capacity of slaughterer's guns. The recent observation of two suicidal head injuries accompanied by skull fractures far away from the bolt's path gave occasion to experimental studies using simulants (glycerin soap, balls from gelatin) and skull–brain models. As far as ballistic soap was concerned, the dimensions of the bolt's channel were assessed by multi-slice computed tomography before cutting the blocks open. The test shots to gelatin balls and to skull-brain models were documented by means of a high-speed motion camera. As expected, the typical temporary cavity effect of bullets fired from conventional guns could not be observed when captive bolt stunners were discharged. Nevertheless, the visualized transfer of kinetic energy justifies the assumption that the secondary fractures seen in thin parts of the skull were caused by a hydraulic burst effect.

  11. Skull Radiography

    MedlinePlus

    What you need to know about… Skull Radiography X-ray images of the skull are taken when it is necessary to see the cranium, facial bones or jaw bones. ... Among other things, x-ray exams of the skull can show fractures. Patient Preparation Before the examination, ...

  12. Intersecting fractures of the skull and gunshot wounds. Case report and literature review.

    PubMed

    Viel, Guido; Gehl, Axel; Sperhake, Jan P

    2009-01-01

    When two fracture lines of a solid surface (ice, glass, eggshell, etc.) intersect, it is always possible to tell which one has been made first. Indeed pre-existing damage of the surface arrests all the fracture lines produced by subsequent impacts. This well-known principle (established by Puppe in 1903) has been largely used in glass fracture analysis, but can be applied also to the examination of skull fractures. It can help sequencing blunt force or gunshot injuries determining the direction of fire and differentiating entrance from exit wounds in the absence of specific distinguishing features (i.e., internal/external beveling of the skull or overlying skin indicators). In this context, we report the case of a 76-year-old man who shot himself in the mouth with a Walther PPK 7.65 handgun and highlight the utility of the application of both Puppe's Rule and Multislice Computed Tomography (MSCT) in the examination of gunshot wounds to the skull.

  13. [On the formation of open skull fractures inflicted by cutting objects].

    PubMed

    Shadymov, A B; Rykunov, I A

    2014-01-01

    The objective of the present work was to study the properties of thrusting weapons, the conditions of their action, and the influence on the formation of cranial vault fractures. The lacerated wounds were simulated using an ordinary axe, native skull and isolated cranial vaults, specially designed multilayer polymeric models of bone and other tissues. This approach made it possible to obtain the objective characteristics of a thrusting blow as a medium-speed thrust (7- 20 m/s) with the impact mass commensurate with or exceeding the weight of the affected object. In indispensable condition for such thrust consists of the counteraction of the forces on a hard substrate. The traumatic agent must have the partially limited and maximally convex contact 1 surface (blade) harder than that of the affected object. Moreover, the character of a lacerated fracture strongly depends on the strin-stress properties of the skull.

  14. The validation and application of a finite element human head model for frontal skull fracture analysis.

    PubMed

    Asgharpour, Z; Baumgartner, D; Willinger, R; Graw, M; Peldschus, S

    2014-05-01

    Traumatic head injuries can result from vehicular accidents, sports, falls or assaults. The current advances in computational methods and the detailed finite element models of the human head provide a significant opportunity for biomechanical study of human head injuries. The biomechanical characteristics of the human head through head impact scenarios can be studied in detail by using the finite element models. Skull fracture is one of the most frequent occurring types of head injuries. The purpose of this study is to analyse the experimental head impacts on cadavers by means of the Strasbourg University Finite Element Head Model (SUFEHM). The results of the numerical model and experimental data are compared for validation purpose. The finite element model has also been applied to predict the skull bone fracture in frontal impacts. The head model includes the scalp, the facial bone, the skull, the cerebral spinal fluid, the meninges, the cerebrum and the cerebellum. The model is used to simulate the experimental frontal head impact tests using a cylindrical padded impactor. Results of the computational simulation shows that the model correlated well with a number of experimental data and a global fracture pattern has been predicted well by the model. Therefore the presented numerical model could be used for reconstruction of head impacts in different impact conditions also the forensic application of the head model would provide a tool for investigation of the causes and mechanism of head injuries.

  15. Bi-Coronal Separated Skull Fracture: A Unique and Fatal Type of Traumatic Head Injury in Infancy: A Case Report.

    PubMed

    Lee, Kyungmin; Park, Ki-Su; Park, Seong Hyun; Hwang, Sung Kyoo

    2014-10-01

    The infantile skull is malleable, and its sutures are tightly adhering to the underlying dura and venous sinus. These characteristics, in association with the small amount of total blood volume, can result in a specific fatal type of skull fracture, which is unique to infancy. The authors report a case of this injury, and stress the need to pay attention to the possibility of massive bleeding during operation in infants. A 23-month-old female baby presented with semicomatose mentality after sustaining injuries by falling from a second-floor. Plain skull films showed bi-frontal skull fracture crossing the midline. Computed tomography revealed an acute subdural hematoma along the right convexity with severe brain edema. In the emergency operation, the scalp incision exposed massive bleeding from the fracture site. The bleeding was identified as arising from the lacerated and widely separated sagittal sinus beneath the fracture. The patient entered hypovolemic shock immediately after the scalp incision, and died from severe brain edema two days after the trauma and surgery. This case implies that special care should be paid during the operation of patients that have skull fracture overlying the venous sinus, especially when the fracture line is separated. PMID:27169046

  16. A simple depressed skull fracture in an old man with Paget disease: forensic implications in a rare case.

    PubMed

    Gitto, Lorenzo; Arunkumar, Ponni; Maiese, Aniello; Bolino, Giorgio

    2015-01-01

    Skull fractures occur when forces striking the head exceed the mechanical integrity of the calvarium. A depressed skull fracture is a break in a cranial bone with depression of the bone into the brain. A depressed fracture may be open (compound), with a skin laceration over the fracture, or closed (simple), when the overlying tissue is not disrupted. The association between simple depressed fracture of the skull and elderly is rare. Paget disease of the bone is a chronic disease characterized by the deposition of abnormal bone tissue, more fragile than normal bone. We report a case of a 92-year-old man who was found supine on the floor in his residence, showing multiple signs of trauma. X-rays and computed tomography scans were performed, showing a simple depressed skull fracture on the right occipital-temporal area and even the characteristics of Paget disease of the skull. The first hypothesis was death due to voluntary homicide. A detailed study of clinical reports, laboratory tests, radiograph scans, and post mortem examination data allowed us to reconstruct the event. Death was finally ruled due to a mild passive trauma, suggesting the unlawful killing of a human without criminal intent, meaning involuntary manslaughter.

  17. [Skull fracture and cephalhematoma in a newborn--a case report].

    PubMed

    Zakanj, Zora

    2014-01-01

    Skull fractures and cephalhematoma in newborns belong to the group of birth injuries of the head and neck, accounting for 11.4 to 15% of the total number of birth injuries. We presented a fracture of the parietal bones in a newborn, associated with parietal cephalhematoma. The newborn had transient and mild neurological symptoms: vomiting and changes in muscle tone. Clinical examination confirmed a positive "ping-pong" phenomen, craniogram confirmed the fracture of parietal bones and shown cephalhematoma, as well as ultrasound (US) examinations of the brain showed peri-interventricular bleeding grade II. After the disappearance of all clinical symptoms in a newborn, we observed total bone healing at the end of the second week of life, and good perinatal outcome. Successful recovery from injury contributes to the ability of rapid bone modeling and remodeling, and brain plasticity. Further interdisciplinary monitoring is very important. PMID:25647994

  18. Elevated fracture of skull in pediatric age group: A series of five patients with review of literature

    PubMed Central

    Kumar, Jayendra; Prakash, Anand; Harsh, Viraat; Kumar, Anil

    2016-01-01

    Elevated fractures of skull in pediatric age group are rarely reported in the literature. In view of rarity, we present a series of five cases of elevated skull fracture in pediatric age group. Over a period of 1-year, we operated on five such cases. In this article, we have discussed the mode, mechanism and extent of injury, its clinico-radiological findings, course of the disease, and the management outcome. Four out of five cases improved after surgery and did not suffer any complications. Early recognition and appropriate management of compound elevated fracture in pediatric age group comes with good outcome and prevents unwanted morbidity and mortality. PMID:26889296

  19. Unusual basal skull fracture in a vehicle equipped with an air bag.

    PubMed

    Bandstra, R A; Carbone, L S

    2001-09-01

    A woman who was the lap/shoulder belt-restrained driver of a car equipped with a full-size air bag was involved in an oblique frontal collision with a tractor-trailer combination. She was extremely out of position, i.e., witnessed to be slumped over the steering wheel before impact. This preimpact positioning led to fatal injuries resulting from the inflating air bag. Postmortem examination showed an unusual partial ring fracture of the base of the skull, which to the authors' knowledge has not previously been reported.

  20. Unusual basal skull fracture in a vehicle equipped with an air bag.

    PubMed

    Bandstra, R A; Carbone, L S

    2001-09-01

    A woman who was the lap/shoulder belt-restrained driver of a car equipped with a full-size air bag was involved in an oblique frontal collision with a tractor-trailer combination. She was extremely out of position, i.e., witnessed to be slumped over the steering wheel before impact. This preimpact positioning led to fatal injuries resulting from the inflating air bag. Postmortem examination showed an unusual partial ring fracture of the base of the skull, which to the authors' knowledge has not previously been reported. PMID:11563734

  1. Skull fracture

    MedlinePlus

    ... necessary. Head injuries may be associated with spinal injuries. Do NOT remove protruding objects. Do NOT allow the person to continue with physical activities. Do NOT forget to watch the person closely until medical help ...

  2. Skull fracture and haemorrhage pattern among fatal and nonfatal head injury assault victims – a critical analysis

    PubMed Central

    Chattopadhyay, Saurabh; Tripathi, Chandrabhal

    2010-01-01

    Abstract: Background: The global incidence of fatal head injuries as the result of assault is greater than the number of non-fatal cases. The important factors that determine the outcome in terms of survival of such head injury cases include the type of weapon used, type and site of skull fracture, intra cranial haemorrhage and the brain injury. The present study aims to highlight the role of skull fractures as an indirect indicator of force of impact and the intra cranial haemorrhage by a comparative study of assault victims with fatal and nonfatal head injuries. Methods: 91 head injury cases resulting from assault were studied in the Department of Forensic Medicine, IMS, BHU Varanasi over a period of 2 years from which 18 patients survived and 73 cases had a lethal outcome. Details of the fatal cases were obtained from the police inquest and an autopsy while examination of the surviving patients was done after obtaining an informed consent. The data so obtained were analyzed and presented in the study. Results: Assault with firearms often led to fatality whereas with assault involving blunt weapons the survival rate was higher. Multiple cranial bones were involved in 69.3% cases while comminuted fracture of the skull was common among the fatal cases. Fracture of the base of the skull was noted only in the fatal cases and a combination of subdural and subarachnoid haemorrhage was found in the majority of the fatal cases. Conclusions: The present study shows skull fractures to be an important indicator of severity of trauma in attacks to the head. Multiple bone fracture, comminuted fracture and base fractures may be considered as high risk factors in attempted homicide cases. PMID:21483205

  3. Role of preoperative 3-dimensional computed tomography reconstruction in depressed skull fractures treated with craniectomy: a case report of forensic interest.

    PubMed

    Viel, Guido; Cecchetto, Giovanni; Manara, Renzo; Cecchetto, Attilio; Montisci, Massimo

    2011-06-01

    Patients affected by cranial trauma with depressed skull fractures and increased intracranial pressure generally undergo neurosurgical intervention. Because craniotomy and craniectomy remove skull fragments and generate new fracture lines, they complicate forensic examination and sometimes prevent a clear identification of skull fracture etiology. A 3-dimensional reconstruction based on preoperative computed tomography (CT) scans, giving a picture of the injuries before surgical intervention, can help the forensic examiner in identifying skull fracture origin and the means of production.We report the case of a 41-year-old-man presenting at the emergency department with a depressed skull fracture at the vertex and bilateral subdural hemorrhage. The patient underwent 2 neurosurgical interventions (craniotomy and craniectomy) but died after 40 days of hospitalization in an intensive care unit. At autopsy, the absence of various bone fragments did not allow us to establish if the skull had been stricken by a blunt object or had hit the ground with high kinetic energy. To analyze bone injuries before craniectomy, a 3-dimensional CT reconstruction based on preoperative scans was performed. A comparative analysis between autoptic and radiological data allowed us to differentiate surgical from traumatic injuries. Moreover, based on the shape and size of the depressed skull fracture (measured from the CT reformations), we inferred that the man had been stricken by a cylindric blunt object with a diameter of about 3 cm. PMID:21512384

  4. Comparative analysis of clinical and computed tomography features of basal skull fractures in head injury in southwestern Nigeria

    PubMed Central

    Olabinri, Eunice O.; Ogbole, Godwin I.; Adeleye, Amos O.; Dairo, David M.; Malomo, Adefolarin O.; Ogunseyinde, Ayotunde O.

    2015-01-01

    Background: Basal skull fractures (BSF) in head injury may be missed clinically. Early detection ensures prompt treatment and prevention of complications We compared the clinical and Computed Tomography (CT) features of basal skull fractures in head injured patients in a southwestern Nigerian hospital. Materials and Methods: Head injury patients who had cranial CT at a Southwestern Nigerian hospital were selected. CT images were acquired with a 64-slice Toshiba Aquillion CT scanner using a standard head protocol. The images were evaluated for evidence of skull fractures, and associated complications. The clinical data and CT findings were analyzed. Results: One hundred and thirty patients were evaluated, including 103 (79.2%) males. Their ages ranged between 7 months and 81 years, mean 35 years (SD, 20.3). In 59 patients (45.4%, 59/130) BSF was detected on CT, while 71 (54.6%) had no evidence BSF. Forty-two (71.2%) of the 59 patients detected on CT had clinical suspicion of BSF (P < 0.001) while the remaining 17 (28.8%) were not clinically diagnosed. This equaled a sensitivity of 71.2% and, specificity of 90.1% for clinical determination of BSF in this study. There was no statistically significant difference between clinical and CT diagnosis (P > 0.05). The commonest observed clinical feature in patients with confirmed BSF was otorrhagia (45.8%) and the petrous temporal bone (45.8%) was the most commonly fractured bone. The BSF was caused most commonly by motor bike accidents in 53 (40.8%). The most common associated intracranial injuries were intracerebral haemorrhage (34.6%) and subdural (17.3%) Conclusion: It appears that neurosurgical evaluation is comparatively reliable in evaluating basal skull fractures in this study area even as they are consistently demonstrated by high resolution CT scanners. A clinical suspicion of BSF should warrant a closer detailed CT evaluation and reporting by radiologists. PMID:25883468

  5. [Depressed skull fracture following the use of Mayfield headrest in adult patients: about a case and review of the literature].

    PubMed

    Moutaoukil, Mohamed; Bensghir, Mustapha; Eddik, Soukaina; Jaafari, Abdelhamid; Ahtil, Redouane; Meziane, Mohammed; Haimeur, Charki

    2016-01-01

    Many neurosurgical procedures involve the use of a pin-type headrest to immobilize the patient's head. We report the case of depressed skull fracture in an adult patient secondary to the use of Mayfield headrest. The diagnosis was based on postoperative CT scan of the brain following surgical resection of medulloblastoma. Several factors seem to increase the risk of complications due to Mayfield headrest use. Preventive measures are outlined in our literature review. PMID:27642467

  6. Prediction of skull fracture risk for children 0-9 months old through validated parametric finite element model and cadaver test reconstruction.

    PubMed

    Li, Zhigang; Liu, Weiguo; Zhang, Jinhuan; Hu, Jingwen

    2015-09-01

    Skull fracture is one of the most common pediatric traumas. However, injury assessment tools for predicting pediatric skull fracture risk is not well established mainly due to the lack of cadaver tests. Weber conducted 50 pediatric cadaver drop tests for forensic research on child abuse in the mid-1980s (Experimental studies of skull fractures in infants, Z Rechtsmed. 92: 87-94, 1984; Biomechanical fragility of the infant skull, Z Rechtsmed. 94: 93-101, 1985). To our knowledge, these studies contained the largest sample size among pediatric cadaver tests in the literature. However, the lack of injury measurements limited their direct application in investigating pediatric skull fracture risks. In this study, 50 pediatric cadaver tests from Weber's studies were reconstructed using a parametric pediatric head finite element (FE) model which were morphed into subjects with ages, head sizes/shapes, and skull thickness values that reported in the tests. The skull fracture risk curves for infants from 0 to 9 months old were developed based on the model-predicted head injury measures through logistic regression analysis. It was found that the model-predicted stress responses in the skull (maximal von Mises stress, maximal shear stress, and maximal first principal stress) were better predictors than global kinematic-based injury measures (peak head acceleration and head injury criterion (HIC)) in predicting pediatric skull fracture. This study demonstrated the feasibility of using age- and size/shape-appropriate head FE models to predict pediatric head injuries. Such models can account for the morphological variations among the subjects, which cannot be considered by a single FE human model.

  7. The oldest anatomical handmade skull of the world c. 1508: 'the ugliness of growing old' attributed to Leonardo da Vinci.

    PubMed

    Missinne, Stefaan J

    2014-06-01

    The author discusses a previously unknown early sixteenth-century renaissance handmade anatomical miniature skull. The small, naturalistic skull made from an agate (calcedonia) stone mixture (mistioni) shows remarkable osteologic details. Dr. Saban was the first to link the skull to Leonardo. The three-dimensional perspective of and the search for the senso comune are discussed. Anatomical errors both in the drawings of Leonardo and this skull are presented. The article ends with the issue of physiognomy, his grotesque faces, the Perspective Communis and his experimenting c. 1508 with the stone mixture and the human skull. Evidence, including the Italian scale based on Crazie and Braccia, chemical analysis leading to a mine in Volterra and Leonardo's search for the soul in the skull are presented. Written references in the inventory of Salai (1524), the inventory of the Villa Riposo (Raffaello Borghini 1584) and Don Ambrogio Mazenta (1635) are reviewed. The author attributes the skull c. 1508 to Leonardo da Vinci.

  8. A device mimicking the biomechanical characteristics of crocodile skull for lumbar fracture reduction.

    PubMed

    Li, Jingmin; Guo, Lihua; Li, Yuancheng; Lei, Zhenkun; Liu, Yuanchang; Shi, Weiping; Li, Tao; Li, Weikang; Liu, Chong

    2016-01-01

    Open surgery is currently the main treatment method for the lumbar burst fracture with neurological deficit but may irreversibly disrupt the lumbar anatomy. The minimally invasive surgery (MIS) techniques have recently gained increasing attention. However, their use is still limited to lumbar burst fractures mainly due to their difficulties in burst fracture reduction and decompression. Here we present a novel bio-inspired MIS device which can be used with an endoscope to reset the bone fragments retropulsed into the spinal canal within the wounded vertebral body. Its head jaw mimics the biomechanical characteristics of a crocodile rostrum to improve the performance in gripping and moving bone pieces in the confined space of a vertebral body. This study may be capable of converting the posterior open surgeries to the MIS procedures, and expands the use of the MIS techniques in the treatment of lumbar burst fractures. PMID:27529133

  9. A history of depressed skull fractures from ancient times to 1800.

    PubMed

    Ganz, Jeremy C; Arndt, Jürgen

    2014-01-01

    The story of managing depressed fractures illustrates how knowledge of proven value does not always get handed down. Celsus was the first to describe sensible management for depressed fractures. As he wrote in Latin this was forgotten. Galen's Greek writings survived forming the basis of management until the sixteenth century. In 1517, Hans von Gersdorff published a formidable illustrated surgical text. One illustration depicts an instrument for elevating depressed bone fragments. It looked dramatic but could not work and its defects were finally defined in the eighteenth century. Ambroise Paré used a bone punch just as we do today, but no later surgeon mentions this, though the instrument was well known. Elements of chance, fashion, emotionally powerful illustrations, and perhaps stubbornness had a profound effect on management delaying rational treatment for centuries.

  10. Basic Imaging of Skull Base Trauma.

    PubMed

    Bobinski, Matthew; Shen, Peter Y; Dublin, Arthur B

    2016-10-01

    Skull base fractures extend through the floor of the anterior, middle, or posterior cranial fossa. They are frequently associated with complex facial fractures and serious complications such as cranial nerve or vascular injury, cerebrospinal fluid leak, or meningitis. Several distinct patterns of skull base fractures have been recognized, each of them associated with different complications. Recognition of, often subtle, skull base fracture is essential to prevent or allow early treatment of these serious complications.

  11. Basic Imaging of Skull Base Trauma.

    PubMed

    Bobinski, Matthew; Shen, Peter Y; Dublin, Arthur B

    2016-10-01

    Skull base fractures extend through the floor of the anterior, middle, or posterior cranial fossa. They are frequently associated with complex facial fractures and serious complications such as cranial nerve or vascular injury, cerebrospinal fluid leak, or meningitis. Several distinct patterns of skull base fractures have been recognized, each of them associated with different complications. Recognition of, often subtle, skull base fracture is essential to prevent or allow early treatment of these serious complications. PMID:27648394

  12. Occurrence and pattern of long bone fractures in growing dogs with normal and osteopenic bones.

    PubMed

    Kumar, K; Mogha, I V; Aithal, H P; Kinjavdekar, P; Singh, G R; Pawde, A M; Kushwaha, R B

    2007-11-01

    A retrospective study was undertaken to record the occurrence and pattern of long bone fractures, and the efficacy of Intramedullary (IM) Steinmann pin fixing in growing dogs. All the records of growing dogs during a 10-year-period were screened to record the cause of trauma, the age and sex of the animal, the bone involved, the type and location of the fracture, the status of fixation, alignment, maintenance of fixation and fracture healing. The results were analysed and comparisons were made between growing dogs with normal and osteopenic bones. Among the 310 cases of fractures recorded, the bones were osteopenic in 91 cases (29%). Minor trauma was the principal cause of fracture in dogs with osteopenia (25%), and indigenous breeds were most commonly affected (38%). Fractures in dogs with osteopenic bones were most commonly recorded in the age group of 2-4 months (53%), whereas fractures in normal dogs were almost equally distributed between 2 and 8 months of age. Male dogs were affected significantly more often in both groups. In osteopenic bones, most fractures were recorded in the femur (56%), and they were distributed equally along the length of the bone. Whereas in normal bones, fractures were almost equally distributed in radius/ulna, femur and tibia, and were more often recorded at the middle and distal third of long bones. Oblique fractures were most common in both groups; however, comminuted fractures were more frequent in normal bones, whereas incomplete fractures were more common in osteopenic bones. Ninety-nine fracture cases treated with IM pinning (66 normal, 33 osteopenic) were evaluated for the status of fracture reduction and healing. In a majority of the cases (61%) with osteopenic bones, the diameter of the pin was relatively smaller than the diameter of the medullary cavity (<70-75%), whereas in 68% of the cases in normal bones the pin diameter was optimum. The status of fracture fixing was satisfactory to good in significantly more

  13. Modeling the Effect of Fluid Flow on a Growing Network of Fractures in a Porous Medium

    NASA Astrophysics Data System (ADS)

    Alhashim, Mohammed; Koch, Donald

    2015-11-01

    The injection of a viscous fluid at high pressure in a geological formation induces the fracturing of pre-existing joints. Assuming a constant solid-matrix stress field, a weak joint saturated with fluid is fractured when the fluid pressure exceeds a critical value that depends on the joint's orientation. In this work, the formation of a network of fractures in a porous medium is modeled. When the average length of the fractures is much smaller than the radius of a cluster of fractured joints, the fluid flow within the network can be described as Darcy flow in a permeable medium consisting of the fracture network. The permeability and porosity of the medium are functions of the number density of activated joints and consequently depend on the fluid pressure. We demonstrate conditions under which these relationships can be derived from percolation theory. Fluid may also be lost from the fracture network by flowing into the permeable rock matrix. The solution of the model shows that the cluster radius grows as a power law with time in two regimes: (1) an intermediate time regime when the network contains many fractures but fluid loss is negligible; and (2) a long time regime when fluid loss dominates. In both regimes, the power law exponent depends on the Euclidean dimension and the injection rate dependence on time.

  14. Skull (image)

    MedlinePlus

    The skull is anterior to the spinal column and is the bony structure that encases the brain. Its purpose ... the facial muscles. The two regions of the skull are the cranial and facial region. The cranial ...

  15. Skull Practice.

    ERIC Educational Resources Information Center

    Slesnick, Irwin L.

    1988-01-01

    Disguises a lesson about skulls with some fun to cause less fear among students. Outlines strategies, questions, and answers for use. Includes a skull mask which can be photocopied and distributed to students as a learning tool and a fun Halloween treat. Also shown is a picture of skull parts. (RT)

  16. Influence of stiffness and shape of contact surface on skull fractures and biomechanical metrics of the human head of different population underlateral impacts.

    PubMed

    Shaoo, Debasis; Deck, Caroline; Yoganandan, Narayan; Willinger, Rémy

    2015-07-01

    The objective of this study was to determine the responses of 5th-percentile female, and 50th- and 95th-percentile male human heads during lateral impacts at different velocities and determine the role of the stiffness and shape of the impacting surface on peak forces and derived skull fracture metrics. A state-of-the-art validated finite element (FE) head model was used to study the influence of different population human heads on skull fracture for lateral impacts. The mass of the FE head model was altered to match the adult size dummies. Numerical simulations of lateral head impacts for 45 cases (15 experiments×3 different population human heads) were performed at velocities ranging from 2.4 to 6.5m/s and three impacting conditions (flat and cylindrical 90D; and flat 40D padding). The entire force-time signals from simulations were compared with experimental mean and upper/lower corridors at each velocity, stiffness (40 and 90 durometer) and shapes (flat and cylindrical) of the impacting surfaces. Average deviation of peak force from the 50th male to 95th male and 5th female were 6.4% and 10.6% considering impacts on the three impactors. These results indicate hierarchy of variables which can be used in injury mitigation efforts.

  17. (Collaboration with the Institut de Physique Nucleaire, Universite de Paris Sud, on use of skull melting techniques to grow ZrO/sub 2/ crystals doped with divalent ions, Orsay, France, March 2--6, 1989): Foreign trip report

    SciTech Connect

    Finch, C.B.

    1989-07-21

    The traveler collaborated with Michel Genet and others at the Institut de Physique Nucleaire to grow CaO-stabilized ZrO/sub 2/ single crystals by the skull technique. This effort was the initial state of a program to produce rare-earth-doped ZrO/sub 2/ single-crystal specimens to be used in spectroscopic studies at both IPN and ORNL. Because of a re-direction in the research priorities at the IPN and the accompanying dearth of funding for this project, this assignment was terminated with the mutual consent of the two institutions.

  18. Solitary plasmocytoma of the skull.

    PubMed

    Gürbüz, Mehmet Sabri; Akmil, Mehmet Ufuk; Akar, Ezgi; Aker, Fügen Vardar

    2013-08-08

    A 63-year-old man presented with a 4-month history of a slowly growing soft mass at his right parieto-occipital region. Neuroradiological examinations revealed an osteolytic extradural tumour of the skull vault. The outer and inner tables of the skull were partially destroyed by the tumour, but the dura was not involved. The tumour and the invaded bone were totally removed and the skull defect was reconstructed using the outer table of the adjacent intact skull. Histopathological examination confirmed plasmocytoma. Laboratory investigations revealed no systemic myelomatosis. It is very important to differentiate solitary plasmocytoma from systemic myelomatosis since their treatment and prognosis are different. Although the prognosis of solitary plasmocytoma is good, regular follow-up examinations are required for any possibility to progress to systemic myelomatosis.

  19. Skull base tumours part I: imaging technique, anatomy and anterior skull base tumours.

    PubMed

    Borges, Alexandra

    2008-06-01

    Advances in cross-sectional imaging, surgical technique and adjuvant treatment have largely contributed to ameliorate the prognosis, lessen the morbidity and mortality of patients with skull base tumours and to the growing medical investment in the management of these patients. Because clinical assessment of the skull base is limited, cross-sectional imaging became indispensable in the diagnosis, treatment planning and follow-up of patients with suspected skull base pathology and the radiologist is increasingly responsible for the fate of these patients. This review will focus on the advances in imaging technique; contribution to patient's management and on the imaging features of the most common tumours affecting the anterior skull base. Emphasis is given to a systematic approach to skull base pathology based upon an anatomic division taking into account the major tissue constituents in each skull base compartment. The most relevant information that should be conveyed to surgeons and radiation oncologists involved in patient's management will be discussed.

  20. Strontium Ranelate Reduces the Fracture Incidence in a Growing Mouse Model of Osteogenesis Imperfecta.

    PubMed

    Shi, Changgui; Hu, Bo; Guo, Lei; Cao, Peng; Tian, Ye; Ma, Jun; Chen, Yuanyuan; Wu, Huiqiao; Hu, Jinquan; Deng, Lianfu; Zhang, Ying; Yuan, Wen

    2016-05-01

    Osteogenesis imperfecta (OI) is a genetic bone dysplasia characterized by brittle bones with increased fracture risk. Although current treatment options to improve bone strength in OI focus on antiresorptive bisphosphonates, controlled clinical trials suggest they have an equivocal effect on reducing fracture risk. Strontium ranelate (SrR) is a promising therapy with a dual mode of action that is capable of simultaneously maintaining bone formation and reducing bone resorption, and may be beneficial for the treatment of OI. In this study, SrR therapy was investigated to assess its effects on fracture frequency and bone mass and strength in an animal model of OI, the oim/oim mouse. Three-week-old oim/oim and wt/wt mice were treated with either SrR or vehicle (Veh) for 11 weeks. After treatment, the average number of fractures sustained by SrR-treated oim/oim mice was significantly reduced compared to Veh-treated oim/oim mice. Micro-computed tomographic (μCT) analyses of femurs showed that both trabecular and cortical bone mass were significantly improved with SrR treatment in both genotypes. SrR significantly inhibited bone resorption, whereas bone formation indices were maintained. Biomechanical testing revealed improved bone structural properties in both oim/oim and wild-type (wt/wt) mice under the treatment, whereas no significant effects on bone brittleness and material quality were observed. In conclusion, SrR was able to effectively reduce fractures in oim/oim mice by improving bone mass and strength and thus represents a potential therapy for the treatment of pediatric OI. © 2015 American Society for Bone and Mineral Research. PMID:26679066

  1. Skull anatomy (image)

    MedlinePlus

    The skull is anterior to the spinal column and is the bony structure that encases the brain. Its purpose ... the facial muscles. The two regions of the skull are the cranial and facial region. The cranial ...

  2. Surgical and Nonsurgical Treatment of Vascular Skull Base Trauma.

    PubMed

    Dahlin, Brian C; Waldau, Ben

    2016-10-01

    Vascular trauma is associated with blunt skull base fractures and penetrating injuries. We review the contemporary management of cranial vascular trauma, including blunt and penetrating cerebrovascular injury as well as refractory epistaxis from facial trauma. PMID:27648396

  3. [Ontogeny and phylogeny of the skull].

    PubMed

    Gawlikowska-Sroka, Aleksandra

    2010-01-01

    Ontogeny of the skull is primarily determined by genetic factors and is modified during development by environmental factors. The shape of the skull and the direction of its development during intrauterine life are determined by the requirements of the growing brain. After birth, the most important role in modifying the shape of the skull is played by large forces from the stomatognathic system. The development of the cranium is fastest during fetal life; at birth, its size is 65% of its final value. After birth, changes in the shape of the skull take place at a slower pace and coincide with eruption of deciduous and permanent teeth, to a lesser degree with formation of the cervical lordosis and other curvatures of the vertebral column. A significant difference has been revealed between times when the skull reaches its final shape and size; adult shape is achieved first. The shape of the human skull has not been constant. Many changes over centuries favored evolution of the neurocranium and involution of the splanchnocranium. They have been provoked by new dietary habits, erect position of the body, alterations and development of the central nervous system, and locomotion type. The dominating features of contemporary man include a reduced splanchnocranium, micrognathia, and retroposition of the mandible. Our studies on medieval and contemporary material have confirmed the narrowing of the face together with shortening and lowering of the skull.

  4. [Anatomy of the skull].

    PubMed

    Pásztor, Emil

    2010-01-01

    The anatomy of the human body based on a special teleological system is one of the greatest miracles of the world. The skull's primary function is the defence of the brain, so every alteration or disease of the brain results in some alteration of the skull. This analogy is to be identified even in the human embryo. Proportions of the 22 bones constituting the skull and of sizes of sutures are not only the result of the phylogeny, but those of the ontogeny as well. E.g. the age of the skeletons in archaeological findings could be identified according to these facts. Present paper outlines the ontogeny and development of the tissues of the skull, of the structure of the bone-tissue, of the changes of the size of the skull and of its parts during the different periods of human life, reflecting to the aesthetics of the skull as well. "Only the human scull can give me an impression of beauty. In spite of all genetical colseness, a skull of a chimpanzee cannot impress me aesthetically"--author confesses. In the second part of the treatise those authors are listed, who contributed to the perfection of our knowledge regarding the skull. First of all the great founder of modern anatomy, Andreas Vesalius, then Pierre Paul Broca, Jacob Benignus Winslow are mentioned here. The most important Hungarian contributors were as follow: Sámuel Rácz, Pál Bugát or--the former assistant of Broca--Aurél Török. A widely used tool for measurement of the size of the skull, the craniometer was invented by the latter. The members of the family Lenhossék have had also important results in this field of research, while descriptive anatomy of the skull was completed by microsopical anatomy thanks the activity of Géza Mihálkovits. PMID:21661257

  5. [Anatomy of the skull].

    PubMed

    Pásztor, Emil

    2010-01-01

    The anatomy of the human body based on a special teleological system is one of the greatest miracles of the world. The skull's primary function is the defence of the brain, so every alteration or disease of the brain results in some alteration of the skull. This analogy is to be identified even in the human embryo. Proportions of the 22 bones constituting the skull and of sizes of sutures are not only the result of the phylogeny, but those of the ontogeny as well. E.g. the age of the skeletons in archaeological findings could be identified according to these facts. Present paper outlines the ontogeny and development of the tissues of the skull, of the structure of the bone-tissue, of the changes of the size of the skull and of its parts during the different periods of human life, reflecting to the aesthetics of the skull as well. "Only the human scull can give me an impression of beauty. In spite of all genetical colseness, a skull of a chimpanzee cannot impress me aesthetically"--author confesses. In the second part of the treatise those authors are listed, who contributed to the perfection of our knowledge regarding the skull. First of all the great founder of modern anatomy, Andreas Vesalius, then Pierre Paul Broca, Jacob Benignus Winslow are mentioned here. The most important Hungarian contributors were as follow: Sámuel Rácz, Pál Bugát or--the former assistant of Broca--Aurél Török. A widely used tool for measurement of the size of the skull, the craniometer was invented by the latter. The members of the family Lenhossék have had also important results in this field of research, while descriptive anatomy of the skull was completed by microsopical anatomy thanks the activity of Géza Mihálkovits.

  6. Skull Base Anatomy.

    PubMed

    Patel, Chirag R; Fernandez-Miranda, Juan C; Wang, Wei-Hsin; Wang, Eric W

    2016-02-01

    The anatomy of the skull base is complex with multiple neurovascular structures in a small space. Understanding all of the intricate relationships begins with understanding the anatomy of the sphenoid bone. The cavernous sinus contains the carotid artery and some of its branches; cranial nerves III, IV, VI, and V1; and transmits venous blood from multiple sources. The anterior skull base extends to the frontal sinus and is important to understand for sinus surgery and sinonasal malignancies. The clivus protects the brainstem and posterior cranial fossa. A thorough appreciation of the anatomy of these various areas allows for endoscopic endonasal approaches to the skull base.

  7. The Royal Book by Haly Abbas from the 10th century: one of the earliest illustrations of the surgical approach to skull fractures.

    PubMed

    Aciduman, Ahmet; Arda, Berna; Kahya, Esin; Belen, Deniz

    2010-12-01

    Haly Abbas was one of the pioneering physicians and surgeons of the Eastern world in the 10th century who influenced the Western world by his monumental work, The Royal Book. The book was first partly translated into Latin by Constantinus Africanus in the 11th century without citing the author's name. Haly Abbas was recognized in Europe after full translation of The Royal Book by Stephen of Antioch in 1127. The Royal Book has been accepted as an early source of jerrah-names (surgical books) in the Eastern world. The chapters regarding cranial fractures in Haly Abbas' work include unique management strategies for his period with essential quotations from Paul of Aegina's work Epitome. Both authors preferred free bone flap craniotomy in cranial fractures. Although Paul of Aegina, a Byzantine physician and surgeon, was a connection between ancient traditions and Islamic interpretation, Haly Abbas seemed to play a bridging role between the Roman-Byzantine and the School of Salerno in Europe.

  8. Fractures

    PubMed Central

    Hall, Michael C.

    1963-01-01

    Recent studies on the epidemiology and repair of fractures are reviewed. The type and severity of the fracture bears a relation to the age, sex and occupation of the patient. Bone tissue after fracture shows a process of inflammation and repair common to all members of the connective tissue family, but it repairs with specific tissue. Cartilage forms when the oxygen supply is outgrown. After a fracture, the vascular bed enlarges. The major blood supply to healing tissue is from medullary vessels and destruction of them will cause necrosis of the inner two-thirds of the cortex. Callus rapidly mineralizes, but full mineralization is achieved slowly; increased mineral metabolism lasts several years after fracture. PMID:13952119

  9. Fractures

    MedlinePlus

    ... commonly happen because of car accidents, falls, or sports injuries. Other causes are low bone density and osteoporosis, which cause weakening of the bones. Overuse can cause stress fractures, which are very small cracks in the ...

  10. Conservative Approach to Unilateral Condylar Fracture in a Growing Patient: A 2.5-Year Follow Up

    PubMed Central

    Tuna, Elif Bahar; Dündar, Aysun; Çankaya, Abdülkadir Burak; Gençay, Koray

    2012-01-01

    Condylar fractures in children are especially important because of the risk of a mandibular growth-center being affected in the condylar head, which can lead to growth retardation and facial asymmetry. The purpose of this article is to follow up the two and half year clinical and radiological evaluation of the conservative treatment of a 10 year-old patient, who had a unilateral green-stick type fracture. The patient presented with painful facial swelling localized over the left condylar region, limited mouth-opening and mandibular deviation to the left. Panoramic radiography and computed tomography confirmed the diagnosis of incomplete fracture on the left condyle with one side of the bone fractured and the other bent. Closed reduction was chosen to allow for initial fibrous union of the fracture segments and remodeling with a normal functional stimulus. A non-rigid mandibular splint was applied in order to remove the direct pressure on the fracture side of the mandible. Clinical and radiologic examination after 30 months revealed uneventful healing with reduction of the condylar head and remodeling of the condylar process following conservative treatment. PMID:22276078

  11. Skull Base Tumors

    NASA Astrophysics Data System (ADS)

    Schulz-Ertner, Daniela

    In skull base tumors associated with a low radiosensitivity for conventional radiotherapy (RT), irradiation with proton or carbon ion beams facilitates a safe and accurate application of high tumor doses due to the favorable beam localization properties of these particle beams. Cranial nerves, the brain stem and normal brain tissue can at the same time be optimally spared.

  12. Anterior skull base oncocytoma.

    PubMed

    López, Fernando; Vivanco, Blanca; Suárez, Carlos; Llorente, José L

    2013-03-01

    Oncocytic neoplasms are tumors composed of oncocytes (ie, epithelial cells with a large cytoplasm that is rich in mitochondria). Most cases are benign and originate from the salivary glands. Although there have been a few reported cases of oncocytomas being found in the sinonasal tract, most if not all cases seem not to involve the anterior skull base. We report a rare case of oncocytoma involving the anterior skull base occurring in a 44-year-old male patient. Preoperative carotid angiography and selective embolization was performed. The patient underwent an expanded endoscopic endonasal anterior craniofacial resection, which allowed complete resection of the tumor, with a low morbidity. The pathological diagnosis was oncocytoma. At 36 months after the initial treatment, the patient is free of disease. Based on our literature search, this may be the first such reported case. A brief review of the available literature examining the known body of knowledge regarding these neoplasms is presented.

  13. Blunt force trauma to skull with various instruments.

    PubMed

    Sulaiman, Nur Amirah; Osman, Khairul; Hamzah, Noor Hazfalinda; Amir, Sri Pawita Albakri

    2014-04-01

    Deaths due to blunt force trauma to the head as a result of assault are some of the most common cases encountered by the practicing forensic pathologist. Previous studies have shown inflicting injury to the head region is one of the most effective methods of murder. The important factors that determine severity of trauma include the type of weapon used, type and site of skull fracture, intracranial haemorrhage and severity of brain injury. The aim of this study was to determine the characteristics of blunt force trauma to the skull produced by different instruments. Nine adult monkeys (Macaca fascicularis) skulls were used as models. Commonly found blunt objects comprising of Warrington hammer, hockey stick and open face helmet were used in this study. A machine calibrated force generator was used to hold the blunt object in place and to hit the skulls at forces of 12.5N and 25N. Resultant traumatic effects and fractures (linear, depressed, basilar, comminuted, and distastic) were analyzed according to type of blunt object used; surface area of contact and absolute force (N/cm(2)) delivered. Results showed that all investigated instruments were capable of producing similar injuries. The severity of trauma was not related to the surface area of contact with the blunt objects. However, only high absolute forces produced comminuted fractures. These findings were observational, as the samples were too small for statistical conclusions.

  14. Congenital depression of the skull in a neonate.

    PubMed

    Tayeh, Christelle; Bali, Bassel; Milad, Nadine; Najjar, Marwan

    2016-01-01

    Congenital depression of the fetal skull is a rare condition. We discuss the case of a 14-days-old male infant, born at term by elective non-complicated caesarean section presenting with a left temporoparietal skull depression. A CT scan was performed which showed no associated fracture. A conservative approach was followed since the infant showed no signs of neurological deficit. Similar cases have been managed successfully in other reports using a conservative approach, with the condition being often self-resolving over the course of a few months. PMID:27605196

  15. Reconstruction of Skull Base Defects.

    PubMed

    Klatt-Cromwell, Cristine N; Thorp, Brian D; Del Signore, Anthony G; Ebert, Charles S; Ewend, Matthew G; Zanation, Adam M

    2016-02-01

    "Endoscopic endonasal skull base surgery has dramatically changed and expanded over recent years due to significant advancements in instrumentation, techniques, and anatomic understanding. With these advances, the need for more robust skull base reconstructive techniques was vital. In this article, reconstructive options ranging from acellular grafts to vascular flaps are described, including the strengths, weaknesses, and common uses."

  16. Skull x-ray

    MedlinePlus

    ... results may be due to: Fracture Tumor Breakdown ( erosion ) or calcium loss of the bone Movement of ... Absence seizure Alzheimer disease Dementia Ear infection - chronic Erosion Friedreich ataxia Hydrocephalus Increased intracranial pressure Malocclusion of ...

  17. Endoscopic Skull Base Surgery

    PubMed Central

    Senior, Brent A

    2008-01-01

    Endoscopic skull base surgery has undergone rapid advancement in the past decade moving from pituitary surgery to suprasellar lesions and now to a myriad of lesions extending from the cribriform plate to C2 and laterally out to the infratemporal fossa and petrous apex. Evolution of several technological advances as well as advances in understanding of endoscopic anatomy and the development of surgical techniques both in resection and reconstruction have fostered this capability. Management of benign disease via endoscopic methods is largely accepted now but more data is needed before the controversy on the role of endoscopic management of malignant disease is decided. Continued advances in surgical technique, navigation systems, endoscopic imaging technology, and robotics assure continued brisk evolution in this expanding field. PMID:19434274

  18. 21 CFR 882.4750 - Skull punch.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Skull punch. 882.4750 Section 882.4750 Food and... NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4750 Skull punch. (a) Identification. A skull punch is a device used to punch holes through a patient's skull to allow fixation of cranioplasty plates...

  19. 21 CFR 882.4750 - Skull punch.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Skull punch. 882.4750 Section 882.4750 Food and... NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4750 Skull punch. (a) Identification. A skull punch is a device used to punch holes through a patient's skull to allow fixation of cranioplasty plates...

  20. 21 CFR 882.4750 - Skull punch.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Skull punch. 882.4750 Section 882.4750 Food and... NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4750 Skull punch. (a) Identification. A skull punch is a device used to punch holes through a patient's skull to allow fixation of cranioplasty plates...

  1. 21 CFR 882.4750 - Skull punch.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Skull punch. 882.4750 Section 882.4750 Food and... NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4750 Skull punch. (a) Identification. A skull punch is a device used to punch holes through a patient's skull to allow fixation of cranioplasty plates...

  2. 21 CFR 882.4750 - Skull punch.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Skull punch. 882.4750 Section 882.4750 Food and... NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4750 Skull punch. (a) Identification. A skull punch is a device used to punch holes through a patient's skull to allow fixation of cranioplasty plates...

  3. Effect of skull flexural properties on brain response during dynamic head loading - biomed 2013.

    PubMed

    Harrigan, T P; Roberts, J C; Ward, E E; Carneal, C M; Merkle, A C

    2013-01-01

    The skull-brain complex is typically modeled as an integrated structure, similar to a fluid-filled shell. Under dynamic loads, the interaction of the skull and the underlying brain, cerebrospinal fluid, and other tissue produces the pressure and strain histories that are the basis for many theories meant to describe the genesis of traumatic brain injury. In addition, local bone strains are of interest for predicting skull fracture in blunt trauma. However, the role of skull flexure in the intracranial pressure response to blunt trauma is complex. Since the relative time scales for pressure and flexural wave transmission across the skull are not easily separated, it is difficult to separate out the relative roles of the mechanical components in this system. This study uses a finite element model of the head, which is validated for pressure transmission to the brain, to assess the influence of skull table flexural stiffness on pressure in the brain and on strain within the skull. In a Human Head Finite Element Model, the skull component was modified by attaching shell elements to the inner and outer surfaces of the existing solid elements that modeled the skull. The shell elements were given the properties of bone, and the existing solid elements were decreased so that the overall stiffness along the surface of the skull was unchanged, but the skull table bending stiffness increased by a factor of 2.4. Blunt impact loads were applied to the frontal bone centrally, using LS-Dyna. The intracranial pressure predictions and the strain predictions in the skull were compared for models with and without surface shell elements, showing that the pressures in the mid-anterior and mid-posterior of the brain were very similar, but the strains in the skull under the loads and adjacent to the loads were decreased 15% with stiffer flexural properties. Pressure equilibration to nearly hydrostatic distributions occurred, indicating that the important frequency components for typical

  4. Imaging of skull base tumours.

    PubMed

    Thust, Stefanie Catherine; Yousry, Tarek

    2016-01-01

    The skull base is a highly complex and difficult to access anatomical region, which constitutes a relatively common site for neoplasms. Imaging plays a central role in establishing the differential diagnosis, to determine the anatomic tumour spread and for operative planning. All skull base imaging should be performed using thin-section multiplanar imaging, whereby CT and MRI can be considered complimentary. An interdisciplinary team approach is central to improve the outcome of these challenging tumours.

  5. A biomechanical evaluation of skull-brain surrogates to blunt high-rate impacts to postmortem human subjects.

    PubMed

    Raymond, David E; Bir, Cynthia A

    2015-03-01

    The field of forensic injury biomechanics is an emerging field. Biomechanically validated tools may assist interdisciplinary teams of investigators in assessing mechanisms of blunt head trauma resulting in skull fractures. The objective of this study is to assess the biofidelity of spherical, frangible skull-brain (SB) surrogates. Blunt impacts were conducted at 20 m/s, using an instrumented 103 g rigid impactor, to the temporo-parietal region of four defleshed cephalic postmortem human subjects (PMHS). Force-deformation response, fracture tolerance, and fracture patterns were recorded for comparison to spherical skull-brain surrogates. Three brain substitutes were assessed: 10% gelatin, lead shot with Styrofoam and water. Force-deformation response of the skull-brain surrogates was similar to defleshed PMHS up to the point of fracture; however, none of the surrogates fractured at tolerance levels comparable to the PMHS. Fracture patterns of the skull-brain surrogates were linear and radiating, while PMHS fractures were all depressed, comminuted. PMID:25572885

  6. Imaging of skull base lesions.

    PubMed

    Kelly, Hillary R; Curtin, Hugh D

    2016-01-01

    Skull base imaging requires a thorough knowledge of the complex anatomy of this region, including the numerous fissures and foramina and the major neurovascular structures that traverse them. Computed tomography (CT) and magnetic resonance imaging (MRI) play complementary roles in imaging of the skull base. MR is the preferred modality for evaluation of the soft tissues, the cranial nerves, and the medullary spaces of bone, while CT is preferred for demonstrating thin cortical bone structure. The anatomic location and origin of a lesion as well as the specific CT and MR findings can often narrow the differential diagnosis to a short list of possibilities. However, the primary role of the imaging specialist in evaluating the skull base is usually to define the extent of the lesion and determine its relationship to vital neurovascular structures. Technologic advances in imaging and radiation therapy, as well as surgical technique, have allowed for more aggressive approaches and improved outcomes, further emphasizing the importance of precise preoperative mapping of skull base lesions via imaging. Tumors arising from and affecting the cranial nerves at the skull base are considered here. PMID:27432686

  7. Imaging of skull base lesions.

    PubMed

    Kelly, Hillary R; Curtin, Hugh D

    2016-01-01

    Skull base imaging requires a thorough knowledge of the complex anatomy of this region, including the numerous fissures and foramina and the major neurovascular structures that traverse them. Computed tomography (CT) and magnetic resonance imaging (MRI) play complementary roles in imaging of the skull base. MR is the preferred modality for evaluation of the soft tissues, the cranial nerves, and the medullary spaces of bone, while CT is preferred for demonstrating thin cortical bone structure. The anatomic location and origin of a lesion as well as the specific CT and MR findings can often narrow the differential diagnosis to a short list of possibilities. However, the primary role of the imaging specialist in evaluating the skull base is usually to define the extent of the lesion and determine its relationship to vital neurovascular structures. Technologic advances in imaging and radiation therapy, as well as surgical technique, have allowed for more aggressive approaches and improved outcomes, further emphasizing the importance of precise preoperative mapping of skull base lesions via imaging. Tumors arising from and affecting the cranial nerves at the skull base are considered here.

  8. The skull of Chios: trepanation in Hippocratic medicine.

    PubMed

    Tsermoulas, Georgios; Aidonis, Asterios; Flint, Graham

    2014-08-01

    Cranial trepanation is the oldest neurosurgical operation and its roots date back to prehistory. For many centuries, religion and mysticism were strongly linked to the cause of diseases, and trepanation was associated with superstitions such as releasing evil spirits from inside the skull. The Hippocratic treatise "On injuries of the head" was therefore a revolutionary work, as it presented a systematic approach to the management of cranial trauma, one that was devoid of spiritual elements. Unfortunately, there are only a limited number of skeletal findings that confirm that the practice of trepanation was performed as part of Hippocratic medicine. In this historical vignette, the authors present a trepanned skull that was found in Chios, Greece, as evidence of the procedure having been performed in accordance with the Hippocratic teaching. The skull bears a parietal bur hole in association with a linear fracture, and it is clear that the patient survived the procedure. In this analysis, the authors examine the application of the original Hippocratic teaching to the skull of Chios. The rationalization of trepanation was clearly a significant achievement in the evolution of neurosurgery.

  9. The skull of Chios: trepanation in Hippocratic medicine.

    PubMed

    Tsermoulas, Georgios; Aidonis, Asterios; Flint, Graham

    2014-08-01

    Cranial trepanation is the oldest neurosurgical operation and its roots date back to prehistory. For many centuries, religion and mysticism were strongly linked to the cause of diseases, and trepanation was associated with superstitions such as releasing evil spirits from inside the skull. The Hippocratic treatise "On injuries of the head" was therefore a revolutionary work, as it presented a systematic approach to the management of cranial trauma, one that was devoid of spiritual elements. Unfortunately, there are only a limited number of skeletal findings that confirm that the practice of trepanation was performed as part of Hippocratic medicine. In this historical vignette, the authors present a trepanned skull that was found in Chios, Greece, as evidence of the procedure having been performed in accordance with the Hippocratic teaching. The skull bears a parietal bur hole in association with a linear fracture, and it is clear that the patient survived the procedure. In this analysis, the authors examine the application of the original Hippocratic teaching to the skull of Chios. The rationalization of trepanation was clearly a significant achievement in the evolution of neurosurgery. PMID:24857244

  10. Submental intubation in maxillofacial fracture: a case report

    PubMed Central

    2016-01-01

    It can be challenging to create a safe airway in maxilla facial fracture and some skull surgeries. In this case study, the patient experienced jaw fractures that disturbed the dental occlusion and associated fracture of the base of the skull. Neither nasal nor oral intubation was possible based on the side effects of tracheotomy; therefore, submental intubation was applied successfully. The procedure and results are presented in the text. PMID:27429940

  11. Missile injuries of the anterior skull base.

    PubMed

    Bhatoe, Harjinder Singh

    2004-02-01

    Missile injuries of the anterior skull base usually occur during war or war-like situations. These injuries may be isolated or associated with multiple traumatic injuries. We report 23 such cases managed during military conflicts and peacekeeping operations. All were adult males. Four of these patients sustained bullet injuries; the rest were injured from shrapnel. Eighteen patients had injury to the visual apparatus with permanent blindness. Proptosis was seen in 16, cerebrospinal fluid (CSF) leak from the wound in seven, and CSF orbitorrhea in three patients. Sixteen had irreparable injury to the eye necessitating evisceration/enucleation, and two had retrobulbar optic nerve injury. Three patients were comatose [Glasgow Coma Scale (GCS) 3/15], and 14 had altered sensorium. Six patients were fully conscious. All were investigated by computed tomography (CT), which revealed injury to the eyeball and skull base, orbital fracture, frontal hematoma, contusion, and pneumocephalus. Seventeen patients underwent emergency surgery, and six patients were initially managed conservatively. Neurosurgical management consisted of making bifrontal flaps, craniotomy/craniectomy, debridement, and repair of the base with fascia lata. Reconstruction of the orbital rim was required in three cases. All were managed postoperatively with cerebral decongestants and antibiotics in anti-meningitic dosages. There was one death in the postoperative period; outcome was good in 16 and moderate in four patients. Twelve patients had retained intracranial splinters; three of these developed recurrent suppurative meningitis. Of the six patients initially managed conservatively, three were subsequently operated for CSF rhinorrhea. Gross communition, dural loss, and injury to the frontal scalp often preclude the use of pericranial repair of the skull base. Fascia lata is extremely useful for reconstruction and repair. Anterior cranial fossa injury probably carries a better prognosis; however, there

  12. Derivation of the mammalian skull vault

    PubMed Central

    MORRISS-KAY, GILLIAN M.

    2001-01-01

    This review describes the evolutionary history of the mammalian skull vault as a basis for understanding its complex structure. Current information on the developmental tissue origins of the skull vault bones (mesoderm and neural crest) is assessed for mammals and other tetrapods. This information is discussed in the context of evolutionary changes in the proportions of the skull vault bones at the sarcopterygian-tetrapod transition. The dual tissue origin of the skull vault is considered in relation to the molecular mechanisms underlying osteogenic cell proliferation and differentiation in the sutural growth centres and in the proportionate contributions of different sutures to skull growth. PMID:11523816

  13. High-resolution interferometric imaging of stress propagation in pediatric and adult skulls

    NASA Astrophysics Data System (ADS)

    Conerty, Michelle D.; Castracane, James; Clow, Lawrence P., Jr.; Koltai, Peter J.; Mouzakes, Jason

    1997-05-01

    Variations based on bone growth and development make stress and fracture propagation differ greatly in pediatric skulls as compared to adult skulls. Differentiating the stress propagation between the pediatric and adult skulls can improve diagnostic prediction when presented with direct frontal impact on a pediatric skull, a fairly common occurrence in the clinical environment. Critical diagnostic information can be learned from an in depth study of stress propagation as a function of impact force at critical locations on the periorbital region of the human skull. The Division of Pediatric Otolaryngology at Albany Medical College and InterScience, Inc. are utilizing electronic speckle pattern interferometry detection (ESPI) and high resolution imaging to evaluate and compare stress propagation in pediatric and adult skulls. A dual detection ESPI system was developed which integrates a medium resolution (2/3') CCD capable of real-time image processing, with a high resolution, megapixel detector capable of limited real time acquisition and image processing in software. Options to allow for high speed detection include integrating a custom, high performance image intensifier with the megapixel detector leg to be used as a high speed gate. The dual optical layout will allow for continuous and pulsed ESPI evaluation of calibrated impacts at specific landmarks on the skull. The goal of this work is to produce a full quantitative analysis of the stress propagation in pediatric versus adult skulls for a better understanding of bone dynamics. The work presented below concentrates on the development of the dual detection ESPI system and initial results achieved with an adult cadaver skull.

  14. Synthesis of Refractory Materials by Skull Melting Technique

    NASA Astrophysics Data System (ADS)

    Osiko, Vyacheslav V.; Borik, Mikhail A.; Lomonova, Elena E.

    This chapter discusses methods of growing refractory oxide single crystals and synthesis of refractory glasses by skull melting technique in a cold crucible. It shows the advantages of radiofrequency (RF) heating of dielectric materials in a cold crucible and points out some specific problems regarding the process of growing crystals by directional crystallization from the melt and by pulling on a seed from the melt. The distinctive features of the method of directional crystallization from the melt are discussed in detail on the example of technology of materials based on zirconia, i.e., cubic single crystals and partly stabilized single crystals. It is shown that the size and quality of crystals are functions of the process conditions, such as thermal conditions under crystallization, growth rate, and chemical composition. We provide an overview of research on the structure, phase composition, and physicochemical properties of crystals based on zirconia. The optical, mechanical, and electric properties of these crystals make them suitable for a number of technical and industrial applications in optics, electronics, materials processing, and medicine. In this chapter, we also consider some problems regarding the synthesis of refractory glasses by skull melting technique. The physicochemical and optical properties of glasses are given and their practical applications in technology are discussed. We note that one of the better developed and most promising applications of skull melting technique is the immobilization of liquid and solid waste (also radioactive waste) into solid-state materials by vitrification.

  15. Imaging of skull base: Pictorial essay

    PubMed Central

    Raut, Abhijit A; Naphade, Prashant S; Chawla, Ashish

    2012-01-01

    The skull base anatomy is complex. Numerous vital neurovascular structures pass through multiple channels and foramina located in the base skull. With the advent of computerized tomography (CT) and magnetic resonance imaging (MRI), accurate preoperative lesion localization and evaluation of its relationship with adjacent neurovascular structures is possible. It is imperative that the radiologist and skull base surgeons are familiar with this complex anatomy for localizing the skull base lesion, reaching appropriate differential diagnosis, and deciding the optimal surgical approach. CT and MRI are complementary to each other and are often used together for the demonstration of the full disease extent. This article focuses on the radiological anatomy of the skull base and discusses few of the common pathologies affecting the skull base. PMID:23833423

  16. Analysis of six Vietnamese trophy skulls.

    PubMed

    Sledzik, P S; Ousley, S

    1991-03-01

    This report presents morphologic, metric, and contextual information on six documented trophy skull specimens confiscated from U.S. servicemen during the Vietnam War. Additional information on the history and occurrence of trophy skull collecting is provided. This sample, consisting mostly of young Vietnamese males, exhibits graffiti, painting, and other evidence of postmortem decorative modification. Identification of trophy skulls is important to medicolegal and anthropological researchers in distinguishing trophy remains from archaeological and forensic specimens.

  17. Diagnosis of Depression in Adolescents Following Traumatic Fracture: A Retrospective Analysis

    PubMed Central

    Irvine, James N.; Madaan, Vishal

    2012-01-01

    Objective: To assess how frequently adolescents are clinically diagnosed with depression following hospitalization for traumatic fracture, with the assumption that a retrospective approach would yield lower rates of depression compared to those reported previously in prospective studies. We hypothesized that depression would be less common among adolescents whose injuries were primarily limited to fractures of the appendicular skeleton, vertebral column, and/or thoracic cage compared to those sustaining concomitant spinal cord and/or brain injuries and those suffering from facial/skull fractures. Method: A patient population of 1,121 adolescents, aged 12 to 19 years, who were hospitalized overnight at the University of Virginia (UVA) Health System, Charlottesville, for fractures between 2000 and 2009, was generated using the health system’s Clinical Data Repository. The number of these adolescents who received a new diagnosis of depression (per ICD-9 codes) at the UVA Health System within the first year following their injury was determined. Results: By the end of the first year, 37 of 913 adolescents (4.1%) who had at least 1 follow-up visit after their fracture were diagnosed with depression. When patients with a concomitant spinal cord injury and those with a facial/skull fracture with or without an associated brain injury were excluded, this percentage dropped to 3.2% and 1.1%, respectively. Conclusions: The results support our initial hypothesis that the percentage of adolescents diagnosed with depression following a traumatic fracture determined retrospectively would be lower than the percentages previously reported in related prospective studies. This finding adds to the growing concern that depression in youth is underdiagnosed, even among youth who have contact with health care providers. When compared to our own retrospectively determined data, the much higher rates of depression reported in several prospective studies indicate that more proactive

  18. Taiwan: growing, growing, gone.

    PubMed

    Hanson, R

    1979-10-01

    Accommodation between Taiwan and the People's Republic of China may not be inconceivable as trade contacts (though officially disallowed) grow. Because of Taiwan's well-established success and the pressing need in China to industrialize, it appears, however, that such an accommodation will occur only after China becomes more like Taiwan. Taiwan owes its success, first, to land reform and then, in the 1960s, to steady industrialization. Besides broad controls over money supply and capital designed to ward off inflationary pressures when needed, and the grand outlines for development, another factor in the island's economic success is that the government has interfered little with private enterprise. The economy has an underpinning of small to medium size businesses. There are more than 10,000 trading companies. This diverse foundation has given the economy as a whole a flexible buffer on which more sophisticated industires can be formed. PMID:12278253

  19. Skull base tumours Part II. Central skull base tumours and intrinsic tumours of the bony skull base.

    PubMed

    Borges, Alexandra

    2008-06-01

    With the advances of cross-sectional imaging radiologists gained an increasing responsibility in the management of patients with skull base pathology. As this anatomic area is hidden to clinical exam, surgeons and radiation oncologists have to rely on imaging studies to plan the most adequate treatment. To fulfil these endeavour radiologists need to be knowledgeable about skull base anatomy, about the main treatment options available, their indications and contra-indications and needs to be aware of the wide gamut of pathologies seen in this anatomic region. This article will provide a radiologists' friendly approach to the central skull base and will review the most common central skull base tumours and tumours intrinsic to the bony skull base.

  20. Skull base chondroblastoma: a case report.

    PubMed

    Moorthy, R K; Daniel, R T; Rajshekhar, V; Chacko, G

    2002-12-01

    Chondroblastoma is a rare tumor of the skull. Temporal bone is the commonest site of involvement in the skull. We present a thirty one year old man who presented with painless swelling over the left temporal bone, which was near totally excised after preoperative embolization. Management of this unusual tumor and its complications are discussed. PMID:12577121

  1. Nose fracture

    MedlinePlus

    Fracture of the nose; Broken nose; Nasal fracture; Nasal bone fracture; Nasal septal fracture ... A fractured nose is the most common fracture of the face. It ... with other fractures of the face. Sometimes a blunt injury can ...

  2. Epidemiology of fragility fractures.

    PubMed

    Friedman, Susan M; Mendelson, Daniel Ari

    2014-05-01

    As the world population of older adults-in particular those over age 85-increases, the incidence of fragility fractures will also increase. It is predicted that the worldwide incidence of hip fractures will grow to 6.3 million yearly by 2050. Fractures result in significant financial and personal costs. Older adults who sustain fractures are at risk for functional decline and mortality, both as a function of fractures and their complications and of the frailty of the patients who sustain fractures. Identifying individuals at high risk provides an opportunity for both primary and secondary prevention.

  3. High-speed documented experimental gunshot to a skull-brain model and radiologic virtual autopsy.

    PubMed

    Thali, Michael J; Kneubuehl, Beat P; Vock, Peter; Allmen, Gabriel v; Dirnhofer, Richard

    2002-09-01

    The authors documented and evaluated experimental gunshots to a skull-brain model with high-speed photography and subsequent radiographic examination for comparison of the morphologic findings in the model. The artificial skull was a polyurethane ball constructed in layers, with a porous diploe sandwiched between a tabula externa and a tabula interna. The brain itself was simulated with gelatin 10% at 4 degrees C, a material well known in wound ballistics. Gunshots were fired at the model from a distance of 10 m and documented with high-speed photography (up to 50 million frames/sec). Subsequently, a complete examination of the artificial skull was performed, including spiral computed tomography (with two-dimensional and three-dimensional reconstructions) and classic skull autopsy. The high-speed photographs clearly showed the dynamic development of the skull fracture system from an external perspective. The subsequent radiographic examination of the entire head volume created two-dimensional reformations in any plane and three-dimensional reconstructions of the gunshot injury of the polyurethane skull-brain model, especially the wound channel and the fracture system. Thanks to the model and high-speed photographs, the dynamic development of the morphology of a gunshot wound could be documented and studied. The data from computed tomography, using two-dimensional and three-dimensional postprocessing with a perspective view, were very similar to those from classic head autopsy, but derived in a hands-off and nondestructive manner. This examination method leads the way to radiographic digital autopsy or virtual autopsy.

  4. Estimation of skull table thickness with clinical CT and validation with microCT.

    PubMed

    Lillie, Elizabeth M; Urban, Jillian E; Weaver, Ashley A; Powers, Alexander K; Stitzel, Joel D

    2015-01-01

    Brain injuries resulting from motor vehicle crashes (MVC) are extremely common yet the details of the mechanism of injury remain to be well characterized. Skull deformation is believed to be a contributing factor to some types of traumatic brain injury (TBI). Understanding biomechanical contributors to skull deformation would provide further insight into the mechanism of head injury resulting from blunt trauma. In particular, skull thickness is thought be a very important factor governing deformation of the skull and its propensity for fracture. Current computed tomography (CT) technology is limited in its ability to accurately measure cortical thickness using standard techniques. A method to evaluate cortical thickness using cortical density measured from CT data has been developed previously. This effort validates this technique for measurement of skull table thickness in clinical head CT scans using two postmortem human specimens. Bone samples were harvested from the skulls of two cadavers and scanned with microCT to evaluate the accuracy of the estimated cortical thickness measured from clinical CT. Clinical scans were collected at 0.488 and 0.625 mm in plane resolution with 0.625 mm thickness. The overall cortical thickness error was determined to be 0.078 ± 0.58 mm for cortical samples thinner than 4 mm. It was determined that 91.3% of these differences fell within the scanner resolution. Color maps of clinical CT thickness estimations are comparable to color maps of microCT thickness measurements, indicating good quantitative agreement. These data confirm that the cortical density algorithm successfully estimates skull table thickness from clinical CT scans. The application of this technique to clinical CT scans enables evaluation of cortical thickness in population-based studies.

  5. Early medical skull surgery for treatment of post-traumatic osteomyelitis 5,000 years ago.

    PubMed

    Petrone, Pierpaolo; Niola, Massimo; Di Lorenzo, Pierpaolo; Paternoster, Mariano; Graziano, Vincenzo; Quaremba, Giuseppe; Buccelli, Claudio

    2015-01-01

    Here we describe the findings of a unique example of the early techniques adopted in neurosurgery around 5000 years ago, consisting in a double well healed skull trephination associated with a post-cranial traumatic event occurring intra vitam to a young male from the Early Chalcolithic cemetery of Pontecagnano (South Italy, ca. 4,900 - 4,500 cal BP). Morphological, X-ray and 3D-CT scan skull-cap evaluation revealed that the main orifice was produced by scraping, obtained by clockwise rotary motion of a right-handed surgeon facing the patient, while the partial trephination was carried out by using a stone point as a drilling tool. In both cases, bone regrowth is indicative of the individual's prolonged postoperative survival and his near-complete recovery. The right femur shows a poorly healed mid-shaft fracture presumably induced by a high energy injury, and a resulting chronic osteomyelitis, affecting both femurs by hematogenous spread of the infection. Our observations on the visual and radiological features of skull and femur lesions, along with evidence on the timing of experimental bone regrowth vs. healing of lower limb fractures associated to long-term bone infections now suggest that this young man underwent a double skull trephination in order to alleviate his extremely painful condition induced by chronic osteomyelitis, which is thought to have been the cause of death.

  6. Early Medical Skull Surgery for Treatment of Post-Traumatic Osteomyelitis 5,000 Years Ago

    PubMed Central

    Petrone, Pierpaolo; Niola, Massimo; Di Lorenzo, Pierpaolo; Paternoster, Mariano; Graziano, Vincenzo; Quaremba, Giuseppe; Buccelli, Claudio

    2015-01-01

    Here we describe the findings of a unique example of the early techniques adopted in neurosurgery around 5000 years ago, consisting in a double well healed skull trephination associated with a post-cranial traumatic event occurring intra vitam to a young male from the Early Chalcolithic cemetery of Pontecagnano (South Italy, ca. 4,900 - 4,500 cal BP). Morphological, X-ray and 3D-CT scan skull-cap evaluation revealed that the main orifice was produced by scraping, obtained by clockwise rotary motion of a right-handed surgeon facing the patient, while the partial trephination was carried out by using a stone point as a drilling tool. In both cases, bone regrowth is indicative of the individual's prolonged postoperative survival and his near-complete recovery. The right femur shows a poorly healed mid-shaft fracture presumably induced by a high energy injury, and a resulting chronic osteomyelitis, affecting both femurs by hematogenous spread of the infection. Our observations on the visual and radiological features of skull and femur lesions, along with evidence on the timing of experimental bone regrowth vs. healing of lower limb fractures associated to long-term bone infections now suggest that this young man underwent a double skull trephination in order to alleviate his extremely painful condition induced by chronic osteomyelitis, which is thought to have been the cause of death. PMID:26018014

  7. Broadband acoustic properties of a murine skull

    NASA Astrophysics Data System (ADS)

    Estrada, Héctor; Rebling, Johannes; Turner, Jake; Razansky, Daniel

    2016-03-01

    It has been well recognized that the presence of a skull imposes harsh restrictions on the use of ultrasound and optoacoustic techniques in the study, treatment and modulation of the brain function. We propose a rigorous modeling and experimental methodology for estimating the insertion loss and the elastic constants of the skull over a wide range of frequencies and incidence angles. A point-source-like excitation of ultrawideband acoustic radiation was induced via the absorption of nanosecond duration laser pulses by a 20 μm diameter microsphere. The acoustic waves transmitted through the skull are recorded by a broadband, spherically focused ultrasound transducer. A coregistered pulse-echo ultrasound scan is subsequently performed to provide accurate skull geometry to be fed into an acoustic transmission model represented in an angular spectrum domain. The modeling predictions were validated by measurements taken from a glass cover-slip and ex vivo adult mouse skulls. The flexible semi-analytical formulation of the model allows for seamless extension to other transducer geometries and diverse experimental scenarios involving broadband acoustic transmission through locally flat solid structures. It is anticipated that accurate quantification and modeling of the skull transmission effects would ultimately allow for skull aberration correction in a broad variety of applications employing transcranial detection or transmission of high frequency ultrasound.

  8. Broadband acoustic properties of a murine skull.

    PubMed

    Estrada, Héctor; Rebling, Johannes; Turner, Jake; Razansky, Daniel

    2016-03-01

    It has been well recognized that the presence of a skull imposes harsh restrictions on the use of ultrasound and optoacoustic techniques in the study, treatment and modulation of the brain function. We propose a rigorous modeling and experimental methodology for estimating the insertion loss and the elastic constants of the skull over a wide range of frequencies and incidence angles. A point-source-like excitation of ultrawideband acoustic radiation was induced via the absorption of nanosecond duration laser pulses by a 20 μm diameter microsphere. The acoustic waves transmitted through the skull are recorded by a broadband, spherically focused ultrasound transducer. A coregistered pulse-echo ultrasound scan is subsequently performed to provide accurate skull geometry to be fed into an acoustic transmission model represented in an angular spectrum domain. The modeling predictions were validated by measurements taken from a glass cover-slip and ex vivo adult mouse skulls. The flexible semi-analytical formulation of the model allows for seamless extension to other transducer geometries and diverse experimental scenarios involving broadband acoustic transmission through locally flat solid structures. It is anticipated that accurate quantification and modeling of the skull transmission effects would ultimately allow for skull aberration correction in a broad variety of applications employing transcranial detection or transmission of high frequency ultrasound.

  9. Management of osteomyelitis of the skull base

    SciTech Connect

    Benecke, J.E. Jr. )

    1989-12-01

    Osteomyelitis of the skull base is the most severe form of malignant otitis externa. As a result of having treated 13 patients with skull base osteomyelitis over a 4-year period, we have developed a method of staging and monitoring this malady using gallium and technetium scanning techniques. Stage I is localized to soft tissues, stage II is limited osteomyelitis, and stage III represents extensive skull base osteomyelitis. All stages are treated with appropriate antipseudomonal antibiotics. The duration of therapy depends upon the clearing of inflammation as shown on the gallium scan. Each case must be looked at independently and not subjected to an arbitrary treatment protocol.

  10. Primary Intraosseous Cavernous Hemangioma in the Skull.

    PubMed

    Yang, Yi; Guan, Jian; Ma, Wenbin; Li, Yongning; Xing, Bing; Ren, Zuyuan; Su, Changbao; Wang, Renzhi

    2016-03-01

    Primary intraosseous cavernous hemangiomas (PICHs) are benign vascular tumors that may involve any part of the body. PICH occurs more frequently in the spine and less commonly in skull. The earliest description in the English literature was in 1845 by Toynbee, who reported a vascular tumor arising in the confines of the parietal bone. Skull PICHs do not always have typical radiologic features and should always be considered in the differential diagnosis of malignant skull lesions. We now reviewed and analyzed related literatures in detail with reporting a rare case of PICH in the left front bone that was surgically resected. PMID:26986133

  11. Primary Intraosseous Cavernous Hemangioma in the Skull

    PubMed Central

    Yang, Yi; Guan, Jian; Ma, Wenbin; Li, Yongning; Xing, Bing; Ren, Zuyuan; Su, Changbao; Wang, Renzhi

    2016-01-01

    Abstract Primary intraosseous cavernous hemangiomas (PICHs) are benign vascular tumors that may involve any part of the body. PICH occurs more frequently in the spine and less commonly in skull. The earliest description in the English literature was in 1845 by Toynbee, who reported a vascular tumor arising in the confines of the parietal bone. Skull PICHs do not always have typical radiologic features and should always be considered in the differential diagnosis of malignant skull lesions. We now reviewed and analyzed related literatures in detail with reporting a rare case of PICH in the left front bone that was surgically resected. PMID:26986133

  12. The genetics of canine skull shape variation.

    PubMed

    Schoenebeck, Jeffrey J; Ostrander, Elaine A

    2013-02-01

    A dog's craniofacial diversity is the result of continual human intervention in natural selection, a process that began tens of thousands of years ago. To date, we know little of the genetic underpinnings and developmental mechanisms that make dog skulls so morphologically plastic. In this Perspectives, we discuss the origins of dog skull shapes in terms of history and biology and highlight recent advances in understanding the genetics of canine skull shapes. Of particular interest are those molecular genetic changes that are associated with the development of distinct breeds.

  13. 21 CFR 882.4030 - Skull plate anvil.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Skull plate anvil. 882.4030 Section 882.4030 Food... DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4030 Skull plate anvil. (a) Identification. A skull plate anvil is a device used to form alterable skull plates in the proper shape to...

  14. 21 CFR 882.4460 - Neurosurgical head holder (skull clamp).

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Neurosurgical head holder (skull clamp). 882.4460... holder (skull clamp). (a) Identification. A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures....

  15. 21 CFR 882.4030 - Skull plate anvil.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Skull plate anvil. 882.4030 Section 882.4030 Food... DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4030 Skull plate anvil. (a) Identification. A skull plate anvil is a device used to form alterable skull plates in the proper shape to...

  16. 21 CFR 882.4460 - Neurosurgical head holder (skull clamp).

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Neurosurgical head holder (skull clamp). 882.4460... holder (skull clamp). (a) Identification. A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures....

  17. 21 CFR 882.4460 - Neurosurgical head holder (skull clamp).

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Neurosurgical head holder (skull clamp). 882.4460... holder (skull clamp). (a) Identification. A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures....

  18. 21 CFR 882.4030 - Skull plate anvil.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Skull plate anvil. 882.4030 Section 882.4030 Food... DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4030 Skull plate anvil. (a) Identification. A skull plate anvil is a device used to form alterable skull plates in the proper shape to...

  19. 21 CFR 882.4030 - Skull plate anvil.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Skull plate anvil. 882.4030 Section 882.4030 Food... DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4030 Skull plate anvil. (a) Identification. A skull plate anvil is a device used to form alterable skull plates in the proper shape to...

  20. 21 CFR 882.4030 - Skull plate anvil.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Skull plate anvil. 882.4030 Section 882.4030 Food... DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4030 Skull plate anvil. (a) Identification. A skull plate anvil is a device used to form alterable skull plates in the proper shape to...

  1. 21 CFR 882.4460 - Neurosurgical head holder (skull clamp).

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Neurosurgical head holder (skull clamp). 882.4460... holder (skull clamp). (a) Identification. A neurosurgical head holder (skull clamp) is a device used to clamp the patient's skull to hold head and neck in a particular position during surgical procedures....

  2. Neurosurgery: Skull Base Craniofacial Trauma.

    PubMed

    Donald, Paul J

    2016-10-01

    Much of craniofacial trauma involves the frontal sinuses. Because of its response to injury, the frontal sinus mucosa has an innate ability to develop mucoceles, and if infected, mucopyocoeles. This article presents a therapeutic algorithm for all forms of craniofacial trauma with concentration on the most severe injury-the through and through fracture and its surgical remediation. PMID:27648398

  3. The Skull of Phyllomedusa sauvagii (Anura, Hylidae).

    PubMed

    Ruiz-Monachesi, Mario R; Lavilla, Esteban O; Montero, Ricardo

    2016-05-01

    The hylid genus Phyllomedusa comprises charismatic frogs commonly known as monkey, leaf or green frogs, and is the most diverse genus of the subfamily Phyllomedusinae, including about 31 species. Although there is some information about the anatomy of these frogs, little is known about the osteology. Here the adult skull of Phyllomedusa sauvagii, both articulated and disarticulated, is described and the intraspecific variation is reported. Additionally, cartilage associated with the adult skull, such as the nasal capsules, auditory apparatus, and hyobranchial apparatus, are included in the analysis. Further examination of disarticulated bones reveals their remarkable complexity, specifically in the sphenethmoid and of the oocipital region. The description of disarticulated bones is useful for the identification of fossil remains as well as providing morphological characteristics that are phylogenetically informative. When comparing the skull morphology with the available information of other species of the genus, Phyllomesusa sauvagii skull resembles more that of P. vaillantii and P. venusta than P. atelopoides. PMID:26916578

  4. Unilateral compressive optic neuropathy due to skull hyperostosis secondary to nutritional vitamin A deficiency.

    PubMed

    Zayed, Mohammed G; Hickman, Simon J; Batty, Ruth; McCloskey, Eugene V; Pepper, Irene M

    2015-01-01

    We report a 17-year-old boy who presented with a chronic left unilateral optic neuropathy. Computerized tomography and magnetic resonance imaging demonstrated compression of the left optic nerve due to skull hyperostosis. He was found to be profoundly vitamin A deficient secondary to an unusual diet consisting predominantly of potato chips and crisps. Skull hyperostosis with cranial neuropathies and other neurological abnormalities has been described in growing animals fed vitamin A deficient diets but has not been previously reported in humans. PMID:26136803

  5. Intracranial pressure and skull remodeling

    PubMed Central

    McCulley, Timothy J.; Jordan Piluek, W.; Chang, Jessica

    2014-01-01

    In this article we review bony changes resulting from alterations in intracranial pressure (ICP) and the implications for ophthalmologists and the patients for whom we care. Before addressing ophthalmic implications, we will begin with a brief overview of bone remodeling. Bony changes seen with chronic intracranial hypotension and hypertension will be discussed. The primary objective of this review was to bring attention to bony changes seen with chronic intracranial hypotension. Intracranial hypotension skull remodeling can result in enophthalmos. In advanced disease enophthalmos develops to a degree that is truly disfiguring. The most common finding for which subjects are referred is ocular surface disease, related to loss of contact between the eyelids and the cornea. Other abnormalities seen include abnormal ocular motility and optic atrophy. Recognition of such changes is important to allow for diagnosis and treatment prior to advanced clinical deterioration. Routine radiographic assessment of bony changes may allow for the identification of patient with abnormal ICP prior to the development of clinically significant disease. PMID:25859141

  6. First nimravid skull from Asia.

    PubMed

    Averianov, Alexander; Obraztsova, Ekaterina; Danilov, Igor; Skutschas, Pavel; Jin, Jianhua

    2016-01-01

    Maofelis cantonensis gen. and sp. nov. is described based on a complete cranium from the middle-upper Eocene Youganwo Formation of Maoming Basin, Guangdong Province, China. The new taxon has characters diagnostic for Nimravidae such as a short cat-like skull, short palate, ventral surface of petrosal dorsal to that of basioccipital, serrations on the distal carina of canine, reduced anterior premolars, and absence of posterior molars (M2-3). It is plesiomorphic nimravid taxon similar to Nimravidae indet. from Quercy (France) in having the glenoid pedicle and mastoid process without ventral projections, a planar basicranium in which the lateral rim is not ventrally buttressed, and P1 present. The upper canine is less flattened than in other Nimravidae. Maofelis cantonensis gen. and sp. nov. exemplifies the earliest stage of development of sabertooth specialization characteristic of Nimravidae. This taxon, together with other middle-late Eocene nimravid records in South Asia, suggests origin and initial diversification of Nimravidae in Asia. We propose that this group dispersed to North America in the late Eocene and to Europe in the early Oligocene. The subsequent Oligocene diversification of Nimravidae took place in North America and Europe, while in Asia this group declined in the Oligocene, likely because of the earlier development of open habitats on that continent. PMID:27161785

  7. First nimravid skull from Asia

    PubMed Central

    Averianov, Alexander; Obraztsova, Ekaterina; Danilov, Igor; Skutschas, Pavel; Jin, Jianhua

    2016-01-01

    Maofelis cantonensis gen. and sp. nov. is described based on a complete cranium from the middle-upper Eocene Youganwo Formation of Maoming Basin, Guangdong Province, China. The new taxon has characters diagnostic for Nimravidae such as a short cat-like skull, short palate, ventral surface of petrosal dorsal to that of basioccipital, serrations on the distal carina of canine, reduced anterior premolars, and absence of posterior molars (M2-3). It is plesiomorphic nimravid taxon similar to Nimravidae indet. from Quercy (France) in having the glenoid pedicle and mastoid process without ventral projections, a planar basicranium in which the lateral rim is not ventrally buttressed, and P1 present. The upper canine is less flattened than in other Nimravidae. Maofelis cantonensis gen. and sp. nov. exemplifies the earliest stage of development of sabertooth specialization characteristic of Nimravidae. This taxon, together with other middle-late Eocene nimravid records in South Asia, suggests origin and initial diversification of Nimravidae in Asia. We propose that this group dispersed to North America in the late Eocene and to Europe in the early Oligocene. The subsequent Oligocene diversification of Nimravidae took place in North America and Europe, while in Asia this group declined in the Oligocene, likely because of the earlier development of open habitats on that continent. PMID:27161785

  8. Emergency skull radiography: the effect of restrictive criteria on skull radiography and CT use

    SciTech Connect

    Baker, S.R.; Gaylord, G.M.; Lantos, G.; Tabaddor, K.; Gallagher, E.J.

    1985-08-01

    A prospective study was performed to determine the effect of restrictive criteria on the use of emergency skull radiography and computed tomography (CT) of the head. Emergency skull radiography required the completion of a special requisition form. Emergency CT of the head was done at the request of senior consultants and was available on a full-time basis. Over 1 year, 2758 skull studies were performed, a decrease of 39.1% when compared with the year before restrictive criteria were instituted, during which 4587 skull examinations were done. In the same period, the number of emergency CT scans of the head increased by 45.7%, from 471 in the control year to 686 in the experimental year. With the use of restrictive criteria, a net savings of $164,000 was achieved. Our results suggest that the use of restrictive criteria is a cost-effective means of limiting skull radiography when CT of the head is readily available.

  9. [A case of multiple trauma with sinking skull, whose life was saved by consistent team medical treatment].

    PubMed

    Iwata, Teruo; Iwamoto, Kensou; Miyazaki, Yuuya; Harayama, Nobuya; Nagato, Masaru; Nihei, Syunichi; Tanigawa, Takahisa; Aibara, Keiji; Kamochi, Masayuki; Nakano, Yoshiteru; Sozen, Takumi; Nishizawa, Shigeru

    2007-06-01

    A 54 year old man was brought to our hospital by ambulance. He had been injured by falling heavy steel. An examination was performed, and he was diag nosed as having sinking skull, acute extradural hematoma, trauma of the righ eye, right eye laceration, injury of the optic canal (right blind), and multipl fractures. Open fractures were observed in the right ring finger and little finger Simple fractures were observed in the zygomatic bone nasal bone and maxillary bone. An emergency operation (external skeletal fixation, taxis of the skull and maxillary bone, extradural hematoma depletion, suture of right eyelid) was performed. His life was saved by consistent team treatment from preoperation t postoperation. He was discharged from our hospital on foot at 45 days after th operation.

  10. Functional Relationship between Skull Form and Feeding Mechanics in Sphenodon, and Implications for Diapsid Skull Development

    PubMed Central

    Curtis, Neil; Jones, Marc E. H.; Shi, Junfen; O'Higgins, Paul; Evans, Susan E.; Fagan, Michael J.

    2011-01-01

    The vertebrate skull evolved to protect the brain and sense organs, but with the appearance of jaws and associated forces there was a remarkable structural diversification. This suggests that the evolution of skull form may be linked to these forces, but an important area of debate is whether bone in the skull is minimised with respect to these forces, or whether skulls are mechanically “over-designed” and constrained by phylogeny and development. Mechanical analysis of diapsid reptile skulls could shed light on this longstanding debate. Compared to those of mammals, the skulls of many extant and extinct diapsids comprise an open framework of fenestrae (window-like openings) separated by bony struts (e.g., lizards, tuatara, dinosaurs and crocodiles), a cranial form thought to be strongly linked to feeding forces. We investigated this link by utilising the powerful engineering approach of multibody dynamics analysis to predict the physiological forces acting on the skull of the diapsid reptile Sphenodon. We then ran a series of structural finite element analyses to assess the correlation between bone strain and skull form. With comprehensive loading we found that the distribution of peak von Mises strains was particularly uniform throughout the skull, although specific regions were dominated by tensile strains while others were dominated by compressive strains. Our analyses suggest that the frame-like skulls of diapsid reptiles are probably optimally formed (mechanically ideal: sufficient strength with the minimal amount of bone) with respect to functional forces; they are efficient in terms of having minimal bone volume, minimal weight, and also minimal energy demands in maintenance. PMID:22216358

  11. Posttraumatic skull films: who needs them

    SciTech Connect

    Freed, H.A.

    1986-03-01

    An effort has been under way for years to make the ordering of skull films in trauma more medically rational. Because the vast majority of skull films have no significant impact on patient management, effort had centered on increasing the yield by limiting radiographs to those who have one or more ''high-yield criteria.'' The publically promulgated high-yield criteria, however, were insufficiently sensitive to pick up some rare occult injuries. Emphasis recently has shifted to low-yield findings (scalp laceration, scalp hematoma, dizziness, headache, and asymptomatic). Although by common practice the presence of one or more of these low-yield findings often results in a skull film, omitting them appears to be extremely safe provided that the patient has no other clinically suspicious findings. Additionally, skull films are no longer the procedure of choice in patients with a neurosurgical emergency. A patient management strategy reflecting recent research is soon to be released with the FDA Skull Panel's final report.

  12. The 'Skull from Bangkok': a skull of a betel quid chewer in the anthropological collection of Rudolf Virchow (Berlin).

    PubMed

    Reichart, Peter A; Creutz, Ulrich; Scheifele, Christian

    2006-08-01

    This report describes the 'Skull from Bangkok', collected by Rudolf Virchow (Berlin, Germany) in the late 19th century. The skull is part of an extensive anthropological collection of skeletons and skulls from all over the world. The skull was probably brought to Berlin during the years 1882-1883. An inscription on the frontal bone gives the name of the skull: 'Skull from Bangkok'. The few remaining teeth of the maxilla show brown black stains because of betel quid chewing. In the collection, there is an extensive number of skulls from South- and Southeast Asia with similar betel stains. Virchow himself was aware of this habit and has described some of the skulls in detail often mentioning the black stains because of betel quid chewing. The Skull from Bangkok is a proof that betel quid chewing was prevalent in Siam of the late 19th century.

  13. Tumors of the anterior skull base.

    PubMed

    Ivan, Michael E; Han, Seunggu J; Aghi, Manish K

    2014-04-01

    A variety of histologic tumor types are present in the anterior skull base. Primary tumors of this area may be derived from the bone, paranasal sinuses, nasopharynx, dura, cranial nerves, pituitary gland and brain. Symptoms are caused mostly through mass effect but, if the tumor becomes aggressive, also through invasion. Selection of surgical approaches to the anterior skull base is based upon balancing risk reduction with maximizing extent of resection. Here we review a spectrum of neoplastic entities found in the anterior skull base in adults and discuss clinical and radiographic presentation, treatment options, and outcomes. Surgical resection remains the mainstay in treatment of these tumors, particularly in the hands of experienced surgeons exercising proper patient and case selection. PMID:24564556

  14. [Injury by skull osteolytic secundary syphilis].

    PubMed

    Alessandro, Lucas; Camporro, Julieta Piar; Arakaki, Naomi; Orellana, Nora; Mora, Claudia Andrea

    2016-04-01

    Bone involvement of syphilis can be observed in tertiary and congenital syphilis. It is infrequent during the secondary stage. The skull is the most affected bone in secondary syphilis, and its most frequent form of presentation is proliferative osteitis. If the skull is affected, headache is usual and can be as intense as in meningitis. Osteolyitic lesions may be seen in complimentary imaging studies, with a moth eaten aspect. These lesions raise concern over a number of differential diagnoses, among which are infectious, inflammatory and neoplastic diseases. The definitive diagnosis is made by bone biopsy of the compromised bone. Molecular techniques in the affected tissues increases diagnostic performance. There is no standardized treatment protocol for syphilis since there are no guidelines available. We report a case of a 19 year old female, presenting with a unique osteolytic lesion in the skull due to secondary syphilis. PMID:27315003

  15. Influences of skull segmentation inaccuracies on EEG source analysis.

    PubMed

    Lanfer, B; Scherg, M; Dannhauer, M; Knösche, T R; Burger, M; Wolters, C H

    2012-08-01

    The low-conducting human skull is known to have an especially large influence on electroencephalography (EEG) source analysis. Because of difficulties segmenting the complex skull geometry out of magnetic resonance images, volume conductor models for EEG source analysis might contain inaccuracies and simplifications regarding the geometry of the skull. The computer simulation study presented here investigated the influences of a variety of skull geometry deficiencies on EEG forward simulations and source reconstruction from EEG data. Reference EEG data was simulated in a detailed and anatomically plausible reference model. Test models were derived from the reference model representing a variety of skull geometry inaccuracies and simplifications. These included erroneous skull holes, local errors in skull thickness, modeling cavities as bone, downward extension of the model and simplifying the inferior skull or the inferior skull and scalp as layers of constant thickness. The reference EEG data was compared to forward simulations in the test models, and source reconstruction in the test models was performed on the simulated reference data. The finite element method with high-resolution meshes was employed for all forward simulations. It was found that large skull geometry inaccuracies close to the source space, for example, when cutting the model directly below the skull, led to errors of 20mm and more for extended source space regions. Local defects, for example, erroneous skull holes, caused non-negligible errors only in the vicinity of the defect. The study design allowed a comparison of influence size, and guidelines for modeling the skull geometry were concluded.

  16. Which Fractures Are Most Attributable to Osteoporosis?

    PubMed Central

    Warriner, Amy H.; Patkar, Nivedita M.; Curtis, Jeffrey R.; Delzell, Elizabeth; Gary, Lisa; Kilgore, Meredith; Saag, Kenneth G.

    2014-01-01

    Background Determining anatomic sites and circumstances under which a fracture may be a consequence of osteoporosis is a topic of ongoing debate and controversy that is important to both clinicians and researchers. Methods We conducted a systematic literature review and generated an evidence report on fracture risk based on specific anatomic bone sites as well as fracture diagnosis codes. Using the RAND/UCLA appropriateness process, we convened a multi-disciplinary panel of 11 experts who rated fractures according to their likelihood of being due to osteoporosis based on the evidence report. Fracture sites (as determined by ICD-CM codes) were stratified by four clinical risk factor categories based on age, sex, race/ethnicity (African- American and Caucasian) and presence or absence of trauma. Results Consistent with current clinical experience, the fractures rated most likely due to osteoporosis were the femoral neck, pathologic fractures of the vertebrae, and lumbar and thoracic vertebral fractures. The fractures rated least likely due to osteoporosis were open proximal humerus fractures, skull, and facial bones. The expert panel rated open fractures of the arm (except proximal humerus) and fractures of the tibia/fibula, patella, ribs, and sacrum as being highly likely due to osteoporosis in older Caucasian women but a lower likelihood in younger African American men. Conclusion Osteoporosis attribution scores for all fracture sites were determined by a multidisciplinary expert panel to provide an evidence-based continuum of the likelihood of a fracture being associated with osteoporosis. PMID:21130353

  17. Synthesis of refractory-oxide materials by skull melting

    SciTech Connect

    Herrick, C.C.; Behrens, R.G.

    1983-01-01

    Skull melting is a cold-crucible technique for obtaining high-purity melts of refractory materials, particularly oxides. This technique has been used to synthesize high-purity minerals and to prepare single crystals of uraninite (UO/sub 2/) and thorianite (ThO/sub 2/) directly from the melt. A description of the crystal-growing technique is discussed. Los Alamos is also interested in developing the skull-melting technique to zone-refine spent UO/sub 2/ nuclear reactor fuel pins. Since metallic fission products and actinides will behave as solute impurities in a UO/sub 2/ solvent, the success of the zone-refining process will depend on the distribution of the impurities between molten and solid UO/sub 2/. An effective distribution coefficient for Y/sub 2/O/sub 3/ segregated between molten and solid UO/sub 2/ was experimentally determined by zone melting. An effective distribution coefficient of k = 0.75 +- 0.05 was obtained, in good agreement with an equilibrium value of k/sub 0/ = 0.6, estimated from the Y/sub 2/O/sub 3/-UO/sub 2/ phase diagram.

  18. CT of Normal Developmental and Variant Anatomy of the Pediatric Skull: Distinguishing Trauma from Normality.

    PubMed

    Idriz, Sanjin; Patel, Jaymin H; Ameli Renani, Seyed; Allan, Rosemary; Vlahos, Ioannis

    2015-01-01

    The use of computed tomography (CT) in clinical practice has been increasing rapidly, with the number of CT examinations performed in adults and children rising by 10% per year in England. Because the radiology community strives to reduce the radiation dose associated with pediatric examinations, external factors, including guidelines for pediatric head injury, are raising expectations for use of cranial CT in the pediatric population. Thus, radiologists are increasingly likely to encounter pediatric head CT examinations in daily practice. The variable appearance of cranial sutures at different ages can be confusing for inexperienced readers of radiologic images. The evolution of multidetector CT with thin-section acquisition increases the clarity of some of these sutures, which may be misinterpreted as fractures. Familiarity with the normal anatomy of the pediatric skull, how it changes with age, and normal variants can assist in translating the increased resolution of multidetector CT into more accurate detection of fractures and confident determination of normality, thereby reducing prolonged hospitalization of children with normal developmental structures that have been misinterpreted as fractures. More important, the potential morbidity and mortality related to false-negative interpretation of fractures as normal sutures may be avoided. The authors describe the normal anatomy of all standard pediatric sutures, common variants, and sutural mimics, thereby providing an accurate and safe framework for CT evaluation of skull trauma in pediatric patients.

  19. Embryonic skulls of titanosaur sauropod dinosaurs.

    PubMed

    Chiappe, L M; Salgado, L; Coria, R A

    2001-09-28

    Little is known about the cranial anatomy of the taxonomically diverse and geographically widespread titanosaurs, a paucity that has hindered inferences about the genealogical history and evolutionary development of the latest sauropod dinosaurs. Newly discovered fossil eggs containing embryonic remains from the Late Cretaceous of Argentina provide the first articulated skulls of titanosaur dinosaurs. The nearly complete fetal skulls shed light on the evolution of some of the most notable cranial features of sauropod dinosaurs, including the retraction of the external nares, the forward rotation of the braincase, and the abbreviation of the infraorbital region. PMID:11577234

  20. Augmented reality-assisted skull base surgery.

    PubMed

    Cabrilo, I; Sarrafzadeh, A; Bijlenga, P; Landis, B N; Schaller, K

    2014-12-01

    Neuronavigation is widely considered as a valuable tool during skull base surgery. Advances in neuronavigation technology, with the integration of augmented reality, present advantages over traditional point-based neuronavigation. However, this development has not yet made its way into routine surgical practice, possibly due to a lack of acquaintance with these systems. In this report, we illustrate the usefulness and easy application of augmented reality-based neuronavigation through a case example of a patient with a clivus chordoma. We also demonstrate how augmented reality can help throughout all phases of a skull base procedure, from the verification of neuronavigation accuracy to intraoperative image-guidance.

  1. Molding of top skull in the treatment of Apert syndrome.

    PubMed

    Shen, Weimin; Cui, Jie; Chen, Jianbin; Weiping, Shen

    2015-03-01

    Patients with Apert syndrome have bilateral coronal craniosynostosis, along with a distinguishing feature of their many deformity, called tower skull. Surgical correction of this deformity is the mainstay of treatment. We describe 3 patients molded top skull after front bone osteotomy orbital bar advancement. This successfully restricted growth of their top skull while allowing growth in other dimensions. Utilization of top-skull molding after cranial surgery shows promise of satisfaction in this setting.

  2. Congenital skull defect and neurofibroma: without scalp and other abnormalities.

    PubMed

    Wang, Jie-Cong; Wei, Liu; Xu, Jia; Liu, Jian-Feng; Gui, Lai

    2012-07-01

    Congenital skull defect is a rare malformation that is usually associated with congenital anomalies of the scalp and comparable lesions in the brain, spinal cord, limbs, and skeletal muscle. Most previously reported cases have described skull defects with aplasia cutis congenita and other congenital abnormalities. Very few patients with skull defects present with an intact scalp or neurofibroma. The authors report an adult patient with a rare congenital skull defect and local neurofibroma.

  3. 21 CFR 882.5960 - Skull tongs for traction.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Skull tongs for traction. 882.5960 Section 882...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5960 Skull tongs for traction. (a) Identification. Skull tongs for traction is an instrument used to immobilize a patient with...

  4. 21 CFR 882.5960 - Skull tongs for traction.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Skull tongs for traction. 882.5960 Section 882...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5960 Skull tongs for traction. (a) Identification. Skull tongs for traction is an instrument used to immobilize a patient with...

  5. 21 CFR 882.5960 - Skull tongs for traction.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Skull tongs for traction. 882.5960 Section 882...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5960 Skull tongs for traction. (a) Identification. Skull tongs for traction is an instrument used to immobilize a patient with...

  6. 21 CFR 882.5960 - Skull tongs for traction.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Skull tongs for traction. 882.5960 Section 882...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5960 Skull tongs for traction. (a) Identification. Skull tongs for traction is an instrument used to immobilize a patient with...

  7. 21 CFR 882.5960 - Skull tongs for traction.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Skull tongs for traction. 882.5960 Section 882...) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Therapeutic Devices § 882.5960 Skull tongs for traction. (a) Identification. Skull tongs for traction is an instrument used to immobilize a patient with...

  8. 21 CFR 882.4460 - Neurosurgical head holder (skull clamp).

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Neurosurgical head holder (skull clamp). 882.4460... (CONTINUED) MEDICAL DEVICES NEUROLOGICAL DEVICES Neurological Surgical Devices § 882.4460 Neurosurgical head holder (skull clamp). (a) Identification. A neurosurgical head holder (skull clamp) is a device used...

  9. Osseous sarcoid with lytic lesions in skull.

    PubMed

    Suri, V; Singh, Abhijai; Das, Reena; Das, Ashim; Malhotra, P; Jain, S; Kumari, S; Khandelwal, N; Varma, S

    2014-04-01

    Sarcoidosis bone is uncommon, and involvement of the skull is exceptionally rare. We present a 65-year-old obese female who presented with a 2-month history of dryness of mouth, polyuria, fatigue, and anorexia. She had generalized lymphadenopathy, organomegaly, and hypercalcemia, and a skeletal survey revealed extensive osteolytic lesions in the skull and phalanges. Both lymph node biopsy from the cervical lymph node and bone marrow examination revealed non-caseating granulomas, suggesting sarcoidosis. She was started on 1 mg/kg oral corticosteroids; during a follow-up of 6 months, she achieved normocalcemia; however, the punched-out lesions in the skull remained unchanged. This case reiterates several important issues that all lymphadenopathy in emerging nations may not be tubercular, and presence of osteolytic lesions in skull are unusual for sarcoid, at an elderly age, necessitates evaluation for more common etiologies like metastases and myeloma. Finally, patients with osseous sarcoid should be on a close follow-up since due to the rarity of this presentation, no definite consensus on the management of such cases exists in the literature.

  10. Forensic and anthropological analysis of human skulls

    NASA Astrophysics Data System (ADS)

    Kinzl, Hans-Peter; Schreiber, Holger

    1990-11-01

    In biology and medicine there are many problems concrninq in vestigations of the human skeleton Beside the long bones the skull is the most important part of the skeleton for m.surement and iden tifiction The fc:e part9 the brain part and the mandibular part of the skul I are qenetical ly determined sectors with high percritage of individual characteristics

  11. Skull Base Tumors: A Kaleidoscope of Challenge

    PubMed Central

    Khanna, J.N.; Natrajan, Srivalli; Galinde, Jyotsna

    2014-01-01

    Resection of skull base lesions has always been riddled with problems like inadequate access, proximity to major vessels, dural tears, cranial nerve damage, and infection. Understanding the modular concept of the facial skeleton has led to the development of transfacial swing osteotomies that facilitates resection in a difficult area with minimal morbidity and excellent cosmetic results. In spite of the current trend toward endonasal endoscopic management of skull base tumors, our series presents nine cases of diverse extensive skull base lesions, 33% of which were recurrent. These cases were approached through different transfacial swing osteotomies through the mandible, a midfacial swing, or a zygomaticotemporal osteotomy as dictated by the three-dimensional spatial location of the lesion, and its extent and proximity to vital structures. Access osteotomies ensured complete removal and good results through the most direct and safe route and good vascular control. This reiterated the fact that transfacial approaches still hold a special place in the management of extensive skull base lesions. PMID:25083368

  12. Porotic hyperostosis and the Gelligaer skull

    PubMed Central

    Cule, John; Evans, I. Lynn

    1968-01-01

    The differential diagnosis of the bony lesions known as porotic hyperostosis found on a Bronze Age child's skull is discussed. Keith and Shattock gave an opinion in 1923 that the cause was rickets. A firm conclusion is not reached in this paper, but it is suggested that it was more likely to have been an iron-deficiency anaemia. Images PMID:5717547

  13. Biophotonics: Through-skull brain imaging

    NASA Astrophysics Data System (ADS)

    Madsen, Steen J.

    2014-09-01

    The use of carbon nanotubes makes it possible to perform fluorescent imaging of cerebral vasculature of mice through their intact skulls. The high spatial and temporal resolution of the non-invasive technique may prove useful for studies of stroke and other brain disorders.

  14. Surgical Resectability of Skull Base Meningiomas

    PubMed Central

    GOTO, Takeo; OHATA, Kenji

    2016-01-01

    With recent advances in surgical technology such as preoperative imaging, neuro-monitoring, and surgical instruments, the surgical resectability of intracranial meningiomas has increased over the last two decades. This study reviewed clinical articles regarding the surgical treatment of meningiomas to clarify the role of surgical excision, with a focus on skull base meningiomas. We sub-classified clinical articles about skull base meningiomas into two categories (anterior and middle fossa meningiomas; and posterior fossa meningiomas) and reviewed papers in each category. In cases with anterior and middle fossa meningiomas, surgical resectability has reached a sufficient level to maximize functional preservation. In cases of posterior fossa meningioma, however, surgical respectability remains insufficient even with full use of recent surgical modalities. Continuous refining of operative procedures is required to obtain more satisfactory outcomes, especially for posterior fossa meningioma. In addition, recent long-term outcomes of stereotactic radiosurgery (SRS) were acceptable for controlling the skull base meningiomas. Therefore, combination with surgical excision and SRS should be considered in complicated skull base meningiomas. PMID:27076382

  15. Primary chondrosarcoma in the skull of a dog

    PubMed Central

    Kim, Heejaung; Itamoto, Kazuhito; Taura, Yasuho

    2007-01-01

    Chondrosarcoma of the skull is a rare primary malignant tumor that is slow-growing, but locally aggressive. A 5-year-old, golden retriever was presented to our hospital with a swelling in the left side of her head, and the swelling had slowly enlarged over the previous month. There were no significant changes on the neurological examination. A computed tomography scan revealed a large mass involving bone destruction and prominent matrix mineralization. T1-weighted magnetic resonance imaging showed a slightly low-signal intensity area and a T2-weighted image revealed marked, high-signal intensity. There was compression of the adjacent brain parenchyma. Histopathological examination confirmed the lesion to be a chondrosarcoma. PMID:17322781

  16. An assessment of the usefulness of a coconut as a model of the human skull for forensic identification of a homicide weapon.

    PubMed

    Pękala, P; Kiełbasa, G; Bogucka, K; Cempa, A; Olszewska, M; Konopka, T

    2014-01-01

    The authors made an attempt to verify if a coconut can be used as a model of human skull to determine the homicide weapon. During our experiment 27 strike attempts were performed with the use of 9 different tools. Among them there were authentic murder weapons and instruments which had been used in similar experiments conducted on human skulls in 1955. Depending on the size of an area in contact with a coconut, weapons caused dents corresponding to the shape of a weapon, irregular fractures or long linear cracks. Our results have shown that coconut can be used as an inexpensive screening model of human skull, but only to determine fractures made by tools with small striking surface.

  17. Statistical analysis of biomechanical properties of the adult skull and age-related structural changes by sex in a Japanese forensic sample.

    PubMed

    Torimitsu, Suguru; Nishida, Yoshifumi; Takano, Tachio; Koizumi, Yoshinori; Makino, Yohsuke; Yajima, Daisuke; Hayakawa, Mutsumi; Inokuchi, Go; Motomura, Ayumi; Chiba, Fumiko; Otsuka, Katsura; Kobayashi, Kazuhiro; Odo, Yuriko; Iwase, Hirotaro

    2014-01-01

    The purpose of this research was to investigate the biomechanical properties of the adult human skull and the structural changes that occur with age in both sexes. The heads of 94 Japanese cadavers (54 male cadavers, 40 female cadavers) autopsied in our department were used in this research. A total of 376 cranial samples, four from each skull, were collected. Sample fracture load was measured by a bending test. A statistically significant negative correlation between the sample fracture load and cadaver age was found. This indicates that the stiffness of cranial bones in Japanese individuals decreases with age, and the risk of skull fracture thus probably increases with age. Prior to the bending test, the sample mass, the sample thickness, the ratio of the sample thickness to cadaver stature (ST/CS), and the sample density were measured and calculated. Significant negative correlations between cadaver age and sample thickness, ST/CS, and the sample density were observed only among the female samples. Computerized tomographic (CT) images of 358 cranial samples were available. The computed tomography value (CT value) of cancellous bone which refers to a quantitative scale for describing radiodensity, cancellous bone thickness and cortical bone thickness were measured and calculated. Significant negative correlation between cadaver age and the CT value or cortical bone thickness was observed only among the female samples. These findings suggest that the skull is substantially affected by decreased bone metabolism resulting from osteoporosis. Therefore, osteoporosis prevention and treatment may increase cranial stiffness and reinforce the skull structure, leading to a decrease in the risk of skull fractures.

  18. Skull defect reconstruction based on a new hybrid level set.

    PubMed

    Zhang, Ziqun; Zhang, Ran; Song, Zhijian

    2014-01-01

    Skull defect reconstruction is an important aspect of surgical repair. Historically, a skull defect prosthesis was created by the mirroring technique, surface fitting, or formed templates. These methods are not based on the anatomy of the individual patient's skull, and therefore, the prosthesis cannot precisely correct the defect. This study presented a new hybrid level set model, taking into account both the global optimization region information and the local accuracy edge information, while avoiding re-initialization during the evolution of the level set function. Based on the new method, a skull defect was reconstructed, and the skull prosthesis was produced by rapid prototyping technology. This resulted in a skull defect prosthesis that well matched the skull defect with excellent individual adaptation.

  19. Biomechanical analysis of biphasic distribution of skull injury in falls from height.

    PubMed

    Park, Sungji; Cha, Jang Gyu; Lee, Youngseok; Seo, Insoo; Lee, Bongwoo; Choi, Youngshik; Choi, Woongchul; Yang, Kyungmoo

    2015-10-01

    Fall from height is one of the most common ways of suicide in Korea. Skull fractures are typically accompanied with these cases, but several autopsy cases show absence of skull fracture even with serious body injuries including sternal and vertebral fracture. The mechanism of this pattern of injury can be explained by impact of facial part on chest or abdomen when the back of the body touches the ground first. We tried to figure out the relevance of this pattern of injury to the height of fall using a computer simulation tool (MADYMO 7.5). For this experiment, a condition of initial pose was limited to leaning forward. The simulation showed that when the body rotated forward, the body parts which got injured by the ground depended on the height of fall. For relatively lower height, head got injured, but as the height was set higher, the point of first impact area changed to the back, hip and then legs. When the body struck first around hip area on supine position, the impact made forceful flexion of lumbar, thoracic and cervical vertebrae, leading to folding the body in two, which resulted in collision between the part of face and the anterior part of body. Through the current investigation, it was explained that the biphasic distribution of the number of head injury cases versus the height distribution was attributed to the forward rotation of the body during the fall. PMID:26159255

  20. Functional structure of the skull in hominoidea.

    PubMed

    Preuschoft, H; Witzel, U

    2004-01-01

    Finite elements stress analysis (FESA) was used to investigate the flow of compressive forces which occur if a homogenous, three-dimensional body representing the skull is loaded by simulated bite forces against the tooth row. Model 1 represents the snout alone. Bite forces are applied simultaneously, but increase rearward. Stresses in the model concentrate along the anterior contour and the lower surface of the model, leaving unstressed a nasal opening and a wide naso-oral connection. Model 2 represents the facial region, as far as the temporomandibular joint. The orbits and the nasal cavity are assumed to be present a priori. Model 3 applies reactions to the bite forces in the temporal fossa, corresponding to the origins of the masticatory muscles. Regions of the model under compressive stress correspond closely to the arrangement of bony material in a hominoid skull. If only the stress-bearing finite elements on each section are combined, and the stress-free parts neglected, the resulting three-dimensional shape is surprisingly similar to a hominoid skull. If bite forces are applied to parts of the tooth row only, the stress patterns are lower, asymmetrical and do not spread into all regions that are stress-bearing in simultaneous biting on all teeth. In model 2, the highest stresses occur at the tooth roots and along the forehead on top of the nasal roof. There are no marked stress concentrations on top of the orbits. The resulting shape resembles that of an orang-utan. In model 3, the highest stresses also occur at the tooth roots, but the circles of force mostly close below the brain case, so that the stress concentration in the forehead region remains much less marked. In this model, however, the stress concentrations are very similar to hollow brow ridges. The entire resulting shape resembles that of gorilla or chimpanzee skulls. A typical gracile australopithecine skull (STS-5) also shows clear similarities to the patterns of stress flow in our models

  1. Functional structure of the skull in hominoidea.

    PubMed

    Preuschoft, H; Witzel, U

    2004-01-01

    Finite elements stress analysis (FESA) was used to investigate the flow of compressive forces which occur if a homogenous, three-dimensional body representing the skull is loaded by simulated bite forces against the tooth row. Model 1 represents the snout alone. Bite forces are applied simultaneously, but increase rearward. Stresses in the model concentrate along the anterior contour and the lower surface of the model, leaving unstressed a nasal opening and a wide naso-oral connection. Model 2 represents the facial region, as far as the temporomandibular joint. The orbits and the nasal cavity are assumed to be present a priori. Model 3 applies reactions to the bite forces in the temporal fossa, corresponding to the origins of the masticatory muscles. Regions of the model under compressive stress correspond closely to the arrangement of bony material in a hominoid skull. If only the stress-bearing finite elements on each section are combined, and the stress-free parts neglected, the resulting three-dimensional shape is surprisingly similar to a hominoid skull. If bite forces are applied to parts of the tooth row only, the stress patterns are lower, asymmetrical and do not spread into all regions that are stress-bearing in simultaneous biting on all teeth. In model 2, the highest stresses occur at the tooth roots and along the forehead on top of the nasal roof. There are no marked stress concentrations on top of the orbits. The resulting shape resembles that of an orang-utan. In model 3, the highest stresses also occur at the tooth roots, but the circles of force mostly close below the brain case, so that the stress concentration in the forehead region remains much less marked. In this model, however, the stress concentrations are very similar to hollow brow ridges. The entire resulting shape resembles that of gorilla or chimpanzee skulls. A typical gracile australopithecine skull (STS-5) also shows clear similarities to the patterns of stress flow in our models

  2. Crystal growing

    NASA Technical Reports Server (NTRS)

    Neville, J. P.

    1990-01-01

    One objective is to demonstrate the way crystals grow and how they affect the behavior of material. Another objective is to compare the growth of crystals in metals and nonmetals. The procedures, which involve a supersaturated solution of a salt that will separate into crystals on cooling and the pouring off of an eutectic solution to expose the crystals formed by a solid solution when an alloy of two metals forms a solid and eutectic solution on cooling, are described.

  3. Imaging of the central skull base.

    PubMed

    Borges, Alexandra

    2009-08-01

    The central skull base (CSB) constitutes a frontier between the extracranial head and neck and the middle cranial fossa. The anatomy of this region is complex, containing most of the bony foramina and canals of the skull base traversed by several neurovascular structures that can act as routes of spread for pathologic processes. Lesions affecting the CSB can be intrinsic to its bony-cartilaginous components; can arise from above, within the intracranial compartment; or can arise from below, within the extracranial head and neck. Crosssectional imaging is indispensable in the diagnosis, treatment planning, and follow-up of patients with CSB lesions. This review focuses on a systematic approach to this region based on an anatomic division that takes into account the major tissue constituents of the CSB.

  4. Imaging of the central skull base.

    PubMed

    Borges, Alexandra

    2009-11-01

    The central skull base (CSB) constitutes a frontier between the extracranial head and neck and the middle cranial fossa. The anatomy of this region is complex, containing most of the bony foramina and canals of the skull base traversed by several neurovascular structures that can act as routes of spread for pathologic processes. Lesions affecting the CSB can be intrinsic to its bony-cartilaginous components; can arise from above, within the intracranial compartment; or can arise from below, within the extracranial head and neck. Crosssectional imaging is indispensable in the diagnosis, treatment planning, and follow-up of patients with CSB lesions. This review focuses on a systematic approach to this region based on an anatomic division that takes into account the major tissue constituents of the CSB.

  5. Osteoradionecrosis of the maxilla and skull base

    SciTech Connect

    Komisar, A.; Silver, C.; Kalnicki, S.

    1985-01-01

    Osteoradionecrosis of the maxilla and base of skull are rare phenomena, usually seen after combined therapy for malignancies of the maxillary sinus. While the mandible is most commonly affected by osteoradionecrosis, the maxilla and skull base may also be affected when preoperative or postoperative radiotherapy is combined with surgery. Contributing factors may be: high radiation dosage delivered to the treatment volume (greater than 6000 rads), loss of tissue protective effects due to surgery, decreased vascularity caused by surgery and radiation, and proximity of a contaminated field. Onset of symptoms may vary. One patient presented 25 years after postoperative radiotherapy. Major symptoms were pain, trismus, and purulent discharge. The best diagnostic modality remains the history and physical exam, as the area is readily accessible. CT scans may be helpful in diagnosis and treatment planning. Therapy should follow time honored principles of local wound care. Home irrigations and hyperbaric therapy have been helpful in encouraging early sequestration and rapid healing.

  6. CT and MR imaging of the central skull base. Part 2. Pathologic spectrum.

    PubMed

    Laine, F J; Nadel, L; Braun, I F

    1990-09-01

    The radiologist must have a thorough knowledge of the normal anatomy and the pathologic spectrum of the skull base to determine the extent of abnormality and to help plan the surgical approach. The authors describe and present examples of congenital, benign, and malignant lesions that affect this region, including cephalocele, fracture, fistula, juvenile angiofibroma, meningioma, chordoma, pituitary adenoma, chondrosarcoma, nasopharyngeal carcinoma, and rhabdomyosarcoma. Metastatic, infectious, and other miscellaneous processes are also discussed. Imaging strategies with computed tomography and magnetic resonance imaging to aid in the diagnosis are suggested.

  7. Congenital malformations of the skull and meninges.

    PubMed

    Kanev, Paul M

    2007-02-01

    The surgery and management of children who have congenital malformations of the skull and meninges require multidisciplinary care and long-term follow-up by multiple specialists in birth defects. The high definition of three-dimensional CT and MRI allows precise surgery planning of reconstruction and management of associated malformations. The reconstruction of meningoencephaloceles and craniosynostosis are challenging procedures that transform the child's appearance. The embryology, clinical presentation, and surgical management of these malformations are reviewed.

  8. Meningioma of the Posterior Skull Base

    PubMed Central

    Biggs, Michael Thomas; Fagan, Paul A.; Sheehy, John P.R.; Bentivoglio, Peter J.; Doust, Bruce D.; Tonkin, John

    1991-01-01

    Combined intratemporal and cerebellopontine angle meningiomas are rejatively rare. There are unsolved problems with the stability of the skull and spine and the lower cranial nerves and there is a marked tendency for the tumor to involve the spinal cord. This article reports on five cases of combined intratemporal and cerebellopontine angle meningiomas. ImagesFigure 1p44-bFigure 2Figure 3Figure 4Figure 5 PMID:17170820

  9. Preoperative embolization of hypervascular skull base tumors.

    PubMed

    Gruber, A; Bavinzski, G; Killer, M; Richling, B

    2000-06-01

    The purpose of the present study is to review the results and complications of preoperative embolization of hypervascular skull base tumors at a neurosurgical center with a team of neurosurgeons cross-experienced in the application of both microsurgery and endovascular techniques. One hundred and twenty-eight endovascular approaches were performed in 66 patients treated for skull base meningiomas (n = 41), paragangliomas of the temporal bone (n = 18), and juvenile nasopharyngeal angiofibromas (n = 7). One death and 2 permanent disabilities were attributable to endovascular therapy. These complications occurred early in our experience (1982-1989) and were related to thromboembolic events rather than complications of transcatheter embolization itself. Our current standard is to perform transfemoral superselective embolizations with either finely corpuscular embolizing substances (PVA particles) or cyanoacrylates (NBCA) under local anesthesia. Using this protocol no embolization-related complications have occurred over the last 9 years. We thus conclude that preoperative embolization of hypervascular skull base tumors can be accomplished safely with the endovascular techniques now available.

  10. Influence of head mass on temporo-parietal skull impact using finite element modeling.

    PubMed

    Sahoo, Debasis; Deck, Caroline; Yoganandan, Narayan; Willinger, Rémy

    2015-09-01

    The effect of head mass on its biomechanical response during lateral impact to the head is investigated in this computational study. The mass of the head of a state-of-the-art validated finite element head model is altered by ± 10 % from the base value of 4.7 kg. Numerical simulations of lateral head impacts for 30 cases (representing 15 human cadaver experiments × 2 mass configurations) are performed using the LS-DYNA solver at different velocities ranging from 2.4 to 6.5 m/s and three impacting conditions representing different stiffness and shapes of the contact/impact surfaces. Results are compared with the original model using the baseline head mass, thus resulting in a total of 45 simulations. Present findings show that the head mass has greater influence for peak interaction forces and the force has a greater dependency on stiffness of contact surface than the shape. Mass variations have also influence on skull strain energy. Regardless of increase/decrease in skull strain energy influenced by head mass variations used in the computational study, the 50 % fracture tolerance limit was unaltered, which was 544 mJ. The present study gives a better understanding of the mechanism of temporo-parietal skull impact.

  11. Cranial trepanation in two skulls of early medieval Italy.

    PubMed

    Facchini, F; Rastelli, E; Ferrero, L; Fulcheri, E

    2003-01-01

    Cranial trepanation is a practice known since prehistory in various, often geographically distant populations. In this work are presented two early medieval trepaned skulls. The first skull comes from Canosa in Apulia (6th-7th c. AD; according to radiocarbon dating), the second is from Ticineto Alessandrino (5th-8th c. AD). The skull of Canosa shows a single perforation on the bregmatic quadrant of the right parietal, whereas the Ticineto skull presents three lesions of different shapes and sizes. Two perforations are on the left parietal and the other is on the right parietal. The lesions of the Ticineto skull can be referred to a therapeutic operation following a trauma, with survival of the individual. In the Canosa skull the absence of a healing reaction suggests a pathological process, without survival of the subject. Moreover, a particular ritual practice cannot be excluded (i.e. a post-mortem trepanation).

  12. Reverse engineering--rapid prototyping of the skull in forensic trauma analysis.

    PubMed

    Kettner, Mattias; Schmidt, Peter; Potente, Stefan; Ramsthaler, Frank; Schrodt, Michael

    2011-07-01

    Rapid prototyping (RP) comprises a variety of automated manufacturing techniques such as selective laser sintering (SLS), stereolithography, and three-dimensional printing (3DP), which use virtual 3D data sets to fabricate solid forms in a layer-by-layer technique. Despite a growing demand for (virtual) reconstruction models in daily forensic casework, maceration of the skull is frequently assigned to ensure haptic evidence presentation in the courtroom. Owing to the progress in the field of forensic radiology, 3D data sets of relevant cases are usually available to the forensic expert. Here, we present a first application of RP in forensic medicine using computed tomography scans for the fabrication of an SLS skull model in a case of fatal hammer impacts to the head. The report is intended to show that this method fully respects the dignity of the deceased and is consistent with medical ethics but nevertheless provides an excellent 3D impression of anatomical structures and injuries.

  13. Role of Endoscopic Skull Base and Keyhole Surgery for Pituitary and Parasellar Tumors Impacting Vision.

    PubMed

    Kelly, Daniel F; Griffiths, Chester F; Takasumi, Yuki; Rhee, John; Barkhoudarian, Garni; Krauss, Howard R

    2015-12-01

    Significant advances over the last 2 decades in imaging technology, instrumentation, anatomical knowledge, and reconstructive techniques have resulted in the endonasal endoscopic approach becoming an integral part of modern skull base surgery. With growing use and greater experience, surgical outcomes continue to incrementally improve across many skull base pathologies, including those tumors that impact vision and ocular motility. The importance of the learning curve and use of a multi-disciplinary approach is critical to maximizing success, minimizing complications, and enhancing quality of life in these patients. Realizing the limits of the endonasal route and reasonable use of transcranial approaches such as the supraorbital eyebrow craniotomy, it may br appropriate to consider nonsurgical therapy including various forms of radiotherapy [corrected] and medical treatment options. PMID:26576016

  14. Imaging of the skull base: anatomy and pathology.

    PubMed

    Policeni, Bruno A; Smoker, Wendy R K

    2015-01-01

    The skull base is a critical landmark, separating intracranial from extracranial structures. This intricate anatomic structure has several foramina and crossing structures, which can be a challenge for novices. Comprehensive anatomic knowledge is critical for narrowing the differential diagnosis of lesions that may affect the skull base. These lesions can be divided into major categories to help in a systematic approach for skull base pathology evaluation.

  15. Device and method for skull-melting depth measurement

    SciTech Connect

    Lauf, R.J.; Heestand, R.L.

    1993-02-09

    A method of skull-melting comprises the steps of: (a) providing a vessel adapted for a skull-melting process, the vessel having an interior, an underside, and an orifice connecting the interior and the underside; (b) disposing a waveguide in the orifice so that the waveguide protrudes sufficiently into the interior to interact with the skull-melting process; (c) providing a signal energy transducer in signal communication with the waveguide; (d) introducing into the vessel a molten working material; (e) carrying out the skull-melting process so that a solidified skull of the working material is formed, the skull and the vessel having an interface therebetween, the skull becoming fused to the waveguide so the signal energy can be transmitted through the waveguide and the skull without interference from the interface; (f) activating the signal energy transducer so that a signal is propagated through the waveguide; and, (g) controlling at least one variable of the skull-melting process utilizing feedback information derived from the propagated signal energy.

  16. Device and method for skull-melting depth measurement

    SciTech Connect

    Lauf, Robert J.; Heestand, Richard L.

    1993-01-01

    A method of skull-melting comprises the steps of: a. providing a vessel adapted for a skull-melting process, the vessel having an interior, an underside, and an orifice in connecting the interior and the underside; b. disposing a waveguide in the orifice so that the waveguide protrudes sufficiently into the interior to interact with the skull-melting process; c. providing a signal energy transducer in signal communication with the waveguide; d. introducing into the vessel a molten working material; e. carrying out the skull-melting process so that a solidified skull of the working material is formed, the skull and the vessel having an interface therebetween, the skull becoming fused to the waveguide so the signal energy can be transmitted through the waveguide and the skull without interference from the interface; f. activating the signal energy transducer so that a signal is propagated through the waveguide; and, g. controlling at least one variable of the skull-melting process utilizing feedback information derived from the propagated signal energy.

  17. [A rare case of lacunar skull deformity associated with craniosynostosis].

    PubMed

    Vaesen, F; Thimmesch, M; Born, J; Misson, J-P

    2016-03-01

    The lacunar skull is a radiologic description characterised by the presence of lacunae in the cranial vault. Its physiopathology remains up to now poorly understood; it is mostly associated with neural tube defects. The association of a lacunar skull with a craniosynostosis has rarely been described in the literature. The case of a 9-month-old patient presenting a multisutural craniosynostosis with a lacunar skull is reported in this article. The surgical treatment allowed to remodel the skull and to hope for a spontaneous regression of the lacunae.

  18. Development of the cetacean nasal skull.

    PubMed

    Klima, M

    1999-01-01

    The adaptation of cetaceans to aquatic life habits is reflected, in their nasal region, in three marked changes from the original relations found in land mammals. These changes include (1) the loss of the sense of smell, (2) translocation of the nostrils from the tip of the rostrum to the vertex of the head, and (3) elongation of the anterior head to form a rostrum protruding far towards anterior. The morphogenetic processes taking place during embryogenesis of the nasal skull play a decisive part in the development of all these changes. The lateral parts of the embryonic nasal capsule, encompassing the nasal passages, change their position from horizontal to vertical. At the same time, the structures of the original nasal floor (the solum nasi) are shifted in front of the nasal passages towards the rostrum. The structures of the original nasal roof (the tectum nasi) and of the nasal side wall (the paries nasi) are translocated behind the nasal passages towards the neurocranium. The medial nasal septum (the septum nasi) mostly loses its connection to the nasal passages and is produced into a point protruding far towards anterior. The transformed embryonic nasal skull of the Cetacea can be divided into three sections: 1. The median structures. These include the cartilaginous structures, viz., the rostrum nasi, the septum interorbitale and the spina mesethmoidalis, which are accompanied by the dermal bones, the vomer and the praemaxillare. In adult cetaceans the rostrum nasi is mostly preserved as a robust cartilage of the skull, which may possibly serve as a sound transmitting structure of the sonar system, or it may be responsible for the sensing of water streams and vibrations. 2. The posterior side wall structures. These include the following cartilaginous structures that are mostly heavily reduced or mutually fused: the cupula nasi anterior, the tectum nasi, the lamina cribrosa, the paries nasi, the commissura orbitonasalis, the cupula nasi posterior, the

  19. Carbon ion radiotherapy of skull base chondrosarcomas

    SciTech Connect

    Schulz-Ertner, Daniela . E-mail: Daniela.Ertner@med.uni-heidelberg.de; Nikoghosyan, Anna; Hof, Holger; Didinger, Bernd; Combs, Stephanie E.; Jaekel, Oliver; Karger, Christian P.; Edler, Lutz; Debus, Juergen

    2007-01-01

    Purpose: To evaluate the effectiveness and toxicity of carbon ion radiotherapy in chondrosarcomas of the skull base. Patients and Methods: Between November 1998 and September 2005, 54 patients with low-grade and intermediate-grade chondrosarcomas of the skull base have been treated with carbon ion radiation therapy (RT) using the raster scan technique at the Gesellschaft fuer Schwerionenforschung in Darmstadt, Germany. All patients had gross residual tumors after surgery. Median total dose was 60 CGE (weekly fractionation 7 x 3.0 CGE). All patients were followed prospectively in regular intervals after treatment. Local control and overall survival rates were calculated using the Kaplan-Meier method. Toxicity was assessed according to the Common Terminology Criteria (CTCAE v.3.0) and Radiation Therapy Oncology Group (RTOG)/European Organization for Research and Treatment of Cancer (EORTC) score. Results: Median follow-up was 33 months (range, 3-84 months). Only 2 patients developed local recurrences. The actuarial local control rates were 96.2% and 89.8% at 3 and 4 years; overall survival was 98.2%at 5 years. Only 1 patient developed a mucositis CTCAE Grade 3; the remaining patients did not develop any acute toxicities >CTCAE Grade 2. Five patients developed minor late toxicities (RTOG/EORTC Grades 1-2), including bilateral cataract (n = 1), sensory hearing loss (n = 1), a reduction of growth hormone (n = 1), and asymptomatic radiation-induced white matter changes of the adjacent temporal lobe (n = 2). Grade 3 late toxicity occurred in 1 patient (1.9%) only. Conclusions: Carbon ion RT is an effective treatment for low- and intermediate-grade chondrosarcomas of the skull base offering high local control rates with low toxicity.

  20. Evolutionary origin of the turtle skull.

    PubMed

    Bever, G S; Lyson, Tyler R; Field, Daniel J; Bhullar, Bhart-Anjan S

    2015-09-10

    Transitional fossils informing the origin of turtles are among the most sought-after discoveries in palaeontology. Despite strong genomic evidence indicating that turtles evolved from within the diapsid radiation (which includes all other living reptiles), evidence of the inferred transformation between an ancestral turtle with an open, diapsid skull to the closed, anapsid condition of modern turtles remains elusive. Here we use high-resolution computed tomography and a novel character/taxon matrix to study the skull of Eunotosaurus africanus, a 260-million-year-old fossil reptile from the Karoo Basin of South Africa, whose distinctive postcranial skeleton shares many unique features with the shelled body plan of turtles. Scepticism regarding the status of Eunotosaurus as the earliest stem turtle arises from the possibility that these shell-related features are the products of evolutionary convergence. Our phylogenetic analyses indicate strong cranial support for Eunotosaurus as a critical transitional form in turtle evolution, thus fortifying a 40-million-year extension to the turtle stem and moving the ecological context of its origin back onto land. Furthermore, we find unexpected evidence that Eunotosaurus is a diapsid reptile in the process of becoming secondarily anapsid. This is important because categorizing the skull based on the number of openings in the complex of dermal bone covering the adductor chamber has long held sway in amniote systematics, and still represents a common organizational scheme for teaching the evolutionary history of the group. These discoveries allow us to articulate a detailed and testable hypothesis of fenestral closure along the turtle stem. Our results suggest that Eunotosaurus represents a crucially important link in a chain that will eventually lead to consilience in reptile systematics, paving the way for synthetic studies of amniote evolution and development.

  1. Evolutionary morphology of the rabbit skull.

    PubMed

    Kraatz, Brian; Sherratt, Emma

    2016-01-01

    The skull of leporids (rabbits and hares) is highly transformed, typified by pronounced arching of the dorsal skull and ventral flexion of the facial region (i.e., facial tilt). Previous studies show that locomotor behavior influences aspects of cranial shape in leporids, and here we use an extensive 3D geometric morphometrics dataset to further explore what influences leporid cranial diversity. Facial tilt angle, a trait that strongly correlates with locomotor mode, significantly predicts the cranial shape variation captured by the primary axis of cranial shape space, and describes a small proportion (13.2%) of overall cranial shape variation in the clade. However, locomotor mode does not correlate with overall cranial shape variation in the clade, because there are two district morphologies of generalist species, and saltators and cursorial species have similar morphologies. Cranial shape changes due to phyletic size change (evolutionary allometry) also describes a small proportion (12.5%) of cranial shape variation in the clade, but this is largely driven by the smallest living leporid, the pygmy rabbit (Brachylagus idahoensis). By integrating phylogenetic history with our geometric morphometric data, we show that the leporid cranium exhibits weak phylogenetic signal and substantial homoplasy. Though these results make it difficult to reconstruct what the 'ancestral' leporid skull looked like, the fossil records suggest that dorsal arching and facial tilt could have occurred before the origin of the crown group. Lastly, our study highlights the diversity of cranial variation in crown leporids, and highlights a need for additional phylogenetic work that includes stem (fossil) leporids and includes morphological data that captures the transformed morphology of rabbits and hares.

  2. Evolutionary origin of the turtle skull.

    PubMed

    Bever, G S; Lyson, Tyler R; Field, Daniel J; Bhullar, Bhart-Anjan S

    2015-09-10

    Transitional fossils informing the origin of turtles are among the most sought-after discoveries in palaeontology. Despite strong genomic evidence indicating that turtles evolved from within the diapsid radiation (which includes all other living reptiles), evidence of the inferred transformation between an ancestral turtle with an open, diapsid skull to the closed, anapsid condition of modern turtles remains elusive. Here we use high-resolution computed tomography and a novel character/taxon matrix to study the skull of Eunotosaurus africanus, a 260-million-year-old fossil reptile from the Karoo Basin of South Africa, whose distinctive postcranial skeleton shares many unique features with the shelled body plan of turtles. Scepticism regarding the status of Eunotosaurus as the earliest stem turtle arises from the possibility that these shell-related features are the products of evolutionary convergence. Our phylogenetic analyses indicate strong cranial support for Eunotosaurus as a critical transitional form in turtle evolution, thus fortifying a 40-million-year extension to the turtle stem and moving the ecological context of its origin back onto land. Furthermore, we find unexpected evidence that Eunotosaurus is a diapsid reptile in the process of becoming secondarily anapsid. This is important because categorizing the skull based on the number of openings in the complex of dermal bone covering the adductor chamber has long held sway in amniote systematics, and still represents a common organizational scheme for teaching the evolutionary history of the group. These discoveries allow us to articulate a detailed and testable hypothesis of fenestral closure along the turtle stem. Our results suggest that Eunotosaurus represents a crucially important link in a chain that will eventually lead to consilience in reptile systematics, paving the way for synthetic studies of amniote evolution and development. PMID:26331544

  3. Evolutionary morphology of the rabbit skull

    PubMed Central

    Sherratt, Emma

    2016-01-01

    The skull of leporids (rabbits and hares) is highly transformed, typified by pronounced arching of the dorsal skull and ventral flexion of the facial region (i.e., facial tilt). Previous studies show that locomotor behavior influences aspects of cranial shape in leporids, and here we use an extensive 3D geometric morphometrics dataset to further explore what influences leporid cranial diversity. Facial tilt angle, a trait that strongly correlates with locomotor mode, significantly predicts the cranial shape variation captured by the primary axis of cranial shape space, and describes a small proportion (13.2%) of overall cranial shape variation in the clade. However, locomotor mode does not correlate with overall cranial shape variation in the clade, because there are two district morphologies of generalist species, and saltators and cursorial species have similar morphologies. Cranial shape changes due to phyletic size change (evolutionary allometry) also describes a small proportion (12.5%) of cranial shape variation in the clade, but this is largely driven by the smallest living leporid, the pygmy rabbit (Brachylagus idahoensis). By integrating phylogenetic history with our geometric morphometric data, we show that the leporid cranium exhibits weak phylogenetic signal and substantial homoplasy. Though these results make it difficult to reconstruct what the ‘ancestral’ leporid skull looked like, the fossil records suggest that dorsal arching and facial tilt could have occurred before the origin of the crown group. Lastly, our study highlights the diversity of cranial variation in crown leporids, and highlights a need for additional phylogenetic work that includes stem (fossil) leporids and includes morphological data that captures the transformed morphology of rabbits and hares. PMID:27688967

  4. Evolutionary morphology of the rabbit skull.

    PubMed

    Kraatz, Brian; Sherratt, Emma

    2016-01-01

    The skull of leporids (rabbits and hares) is highly transformed, typified by pronounced arching of the dorsal skull and ventral flexion of the facial region (i.e., facial tilt). Previous studies show that locomotor behavior influences aspects of cranial shape in leporids, and here we use an extensive 3D geometric morphometrics dataset to further explore what influences leporid cranial diversity. Facial tilt angle, a trait that strongly correlates with locomotor mode, significantly predicts the cranial shape variation captured by the primary axis of cranial shape space, and describes a small proportion (13.2%) of overall cranial shape variation in the clade. However, locomotor mode does not correlate with overall cranial shape variation in the clade, because there are two district morphologies of generalist species, and saltators and cursorial species have similar morphologies. Cranial shape changes due to phyletic size change (evolutionary allometry) also describes a small proportion (12.5%) of cranial shape variation in the clade, but this is largely driven by the smallest living leporid, the pygmy rabbit (Brachylagus idahoensis). By integrating phylogenetic history with our geometric morphometric data, we show that the leporid cranium exhibits weak phylogenetic signal and substantial homoplasy. Though these results make it difficult to reconstruct what the 'ancestral' leporid skull looked like, the fossil records suggest that dorsal arching and facial tilt could have occurred before the origin of the crown group. Lastly, our study highlights the diversity of cranial variation in crown leporids, and highlights a need for additional phylogenetic work that includes stem (fossil) leporids and includes morphological data that captures the transformed morphology of rabbits and hares. PMID:27688967

  5. Evolutionary morphology of the rabbit skull

    PubMed Central

    Sherratt, Emma

    2016-01-01

    The skull of leporids (rabbits and hares) is highly transformed, typified by pronounced arching of the dorsal skull and ventral flexion of the facial region (i.e., facial tilt). Previous studies show that locomotor behavior influences aspects of cranial shape in leporids, and here we use an extensive 3D geometric morphometrics dataset to further explore what influences leporid cranial diversity. Facial tilt angle, a trait that strongly correlates with locomotor mode, significantly predicts the cranial shape variation captured by the primary axis of cranial shape space, and describes a small proportion (13.2%) of overall cranial shape variation in the clade. However, locomotor mode does not correlate with overall cranial shape variation in the clade, because there are two district morphologies of generalist species, and saltators and cursorial species have similar morphologies. Cranial shape changes due to phyletic size change (evolutionary allometry) also describes a small proportion (12.5%) of cranial shape variation in the clade, but this is largely driven by the smallest living leporid, the pygmy rabbit (Brachylagus idahoensis). By integrating phylogenetic history with our geometric morphometric data, we show that the leporid cranium exhibits weak phylogenetic signal and substantial homoplasy. Though these results make it difficult to reconstruct what the ‘ancestral’ leporid skull looked like, the fossil records suggest that dorsal arching and facial tilt could have occurred before the origin of the crown group. Lastly, our study highlights the diversity of cranial variation in crown leporids, and highlights a need for additional phylogenetic work that includes stem (fossil) leporids and includes morphological data that captures the transformed morphology of rabbits and hares.

  6. Development of a skull/brain model for military wound ballistics studies.

    PubMed

    Carr, Debra; Lindstrom, Anne-Christine; Jareborg, Andreas; Champion, Stephen; Waddell, Neil; Miller, David; Teagle, Michael; Horsfall, Ian; Kieser, Jules

    2015-05-01

    Reports on penetrating ballistic head injuries in the literature are dominated by case studies of suicides; the penetrating ammunition usually being .22 rimfire or shotgun. The dominating cause of injuries in modern warfare is fragmentation and hence, this is the primary threat that military helmets protect the brain from. When helmets are perforated, this is usually by bullets. In combat, 20% of penetrating injuries occur to the head and its wounding accounts for 50% of combat deaths. A number of head simulants are described in the academic literature, in ballistic test methods for helmets (including measurement of behind helmet blunt trauma, BHBT) and in the 'open' and 'closed' government literature of several nations. The majority of these models are not anatomically correct and are not assessed with high-velocity rifle ammunition. In this article, an anatomically correct 'skull' (manufactured from polyurethane) and 'brain' (manufactured from 10%, by mass, gelatine) model for use in military wound ballistic studies is described. Filling the cranium completely with gelatine resulted in a similar 'skull' fracture pattern as an anatomically correct 'brain' combined with a representation of cerebrospinal fluid. In particular, posterior cranial fossa and occipital fractures and brain ejection were observed. This pattern of injury compared favourably to reported case studies of actual incidents in the literature. PMID:25194710

  7. Development of a skull/brain model for military wound ballistics studies.

    PubMed

    Carr, Debra; Lindstrom, Anne-Christine; Jareborg, Andreas; Champion, Stephen; Waddell, Neil; Miller, David; Teagle, Michael; Horsfall, Ian; Kieser, Jules

    2015-05-01

    Reports on penetrating ballistic head injuries in the literature are dominated by case studies of suicides; the penetrating ammunition usually being .22 rimfire or shotgun. The dominating cause of injuries in modern warfare is fragmentation and hence, this is the primary threat that military helmets protect the brain from. When helmets are perforated, this is usually by bullets. In combat, 20% of penetrating injuries occur to the head and its wounding accounts for 50% of combat deaths. A number of head simulants are described in the academic literature, in ballistic test methods for helmets (including measurement of behind helmet blunt trauma, BHBT) and in the 'open' and 'closed' government literature of several nations. The majority of these models are not anatomically correct and are not assessed with high-velocity rifle ammunition. In this article, an anatomically correct 'skull' (manufactured from polyurethane) and 'brain' (manufactured from 10%, by mass, gelatine) model for use in military wound ballistic studies is described. Filling the cranium completely with gelatine resulted in a similar 'skull' fracture pattern as an anatomically correct 'brain' combined with a representation of cerebrospinal fluid. In particular, posterior cranial fossa and occipital fractures and brain ejection were observed. This pattern of injury compared favourably to reported case studies of actual incidents in the literature.

  8. Skull Base Inverted Papilloma: A Comprehensive Review

    PubMed Central

    Wassef, Shafik N.; Batra, Pete S.; Barnett, Samuel

    2012-01-01

    Skull base inverted papilloma (IP) is an unusual entity for many neurosurgeons. IP is renowned for its high rate of recurrence, its ability to cause local destruction, and its association with malignancy. This paper is a comprehensive review of the reports, studies, and reviews published in the current biomedical literature from 1947 to September 2010 and synthesize this information to focus on its potential invasion to the base of the skull and possible intradural extension. The objective is to familiarize the clinician with the different aspects of this unusual disease. The role of modern diagnostic tools in medical imaging in order to assess clearly the limits of the tumors and to enhance the efficiency and the safety in the choice of a surgical approach is pointed out. The treatment guidelines for IP have undergone a complex evolution that continues today. Radical excision of the tumour is technically difficult and often incomplete. Successful management of IP requires resection of the affected mucosa which could be achieved with open surgery, endoscopic, or combined approach. Radio and chemotherapy were used for certain indications. More optimally research would be a multicenter randomized trials with large size cohorts. PMID:23346418

  9. Supratentorial meningiomas of the skull base

    NASA Astrophysics Data System (ADS)

    Maira, G.; Amante, P. R.; Anile, C.; Carletti, S.

    1996-12-01

    Different lasers are today used in many neurosurgical centers, in clinical practice or in basic and clinical research. Even if the laser effects have been studied in other pathological conditions, the laser technology has been mostly applied to the treatment of intracranial tumors. This paper will be mainly concerned with the aspects of surgical technique regarding the supratentorial meningiomas of the skull base, derived from our experience with a series of skull base meningiomas operated on between January 1981 and July 1996. The subject of our analysis are 110 patients who underwent a total of 121 operations. In addition to simple bipolar coagulation and removal of the mass in small coagulated fragments, we have utilized various lasers with different sources of emission, namely CO2, Argon and Nd:YAG. The CO2 laser was utilized in 10 cases, the Argon laser in 2 cases and the Nd:YAG laser in 27 cases in both the contact and remote modalities. Among these last 27 patients a total removal was achieved in 96 percent, against 86 percent obtained in the remaining 83 meningiomas. Six patients were reoperated on for recurrences; none of them had been operated on using the Nd:YAG laser.

  10. Glottic and skull indices in canine brachycephalic airway obstructive syndrome

    PubMed Central

    2014-01-01

    Background Forty dogs presented for brachycephalic airway obstructive syndrome with laryngeal collapse not over 1st degree (saccule eversion) underwent glottis endoscopic and radiographic skull measurements before surgery. Fifteen Pugs, fifteen French and ten English Bulldogs were included. The goals were prospectively to compare three common brachycephalic breeds for anatomical differences regarding glottis and skull measurements, and to assess if any correlation between glottis and skull measurements was present. Linear measurements were used to obtain glottis and skull indices. Correlations between glottis and skull indices and glottic measurements were evaluated. Finally, glottis indices were compared among the three breeds. Results No correlation was found for glottis and skull indices. The glottic index differed among the three breeds (smaller in Pugs and higher in English Bulldogs), ultimately representing a morphologic indicator of the different larynx shape in the three breeds (more rounded in English Bulldogs, more elliptical in Pugs and in-between in French Bulldogs). Conclusions The lack of correlation between skull/glottic indices does not support skull morphology as predictor of glottic morphology. As Pugs had the lowest glottic index, it may be speculated that Pugs’ original narrow glottic width may predispose to further progressive respiratory deterioration more easily than in the other two breeds. PMID:24410902

  11. High activity iodine 125 endocurietherapy for recurrent skull base tumors

    SciTech Connect

    Kumar, P.P.; Good, R.R.; Leibrock, L.G.; Mawk, J.R.; Yonkers, A.J.; Ogren, F.P.

    1988-04-15

    Experience with endocurietherapy of skull base tumors is reviewed. We present our cases of recurrent pituitary hemangiopericytoma, radiation-induced recurrent meningioma, recurrent clival chordoma, recurrent nasopharyngeal cancer involving the cavernous sinus, and recurrent parotid carcinoma of the skull base which were all successfully retreated with high-activity 125-iodine (I-125) permanent implantation.76 references.

  12. Molecularly proven hypochondroplasia with cloverleaf skull deformity: a novel association.

    PubMed

    Angle, B; Hersh, J H; Christensen, K M

    1998-11-01

    We report on a case of cloverleaf skull deformity in a patient with hypochondroplasia, a disorder which has not been previously associated with this anomaly. Hypochondroplasia is a bone dysplasia caused by mutations in the fibroblast growth factor receptor 3 (FGFR3) gene. Cloverleaf skull is a trilobar skull deformity which is etiologically and genetically heterogeneous and occurs in association with a number of disorders which result from mutations in the fibroblast growth factor receptor genes. Our patient demonstrated one of the common FGFR3 mutations identified in hypochondroplasia, a C-to-A change at nucleotide 1620 (C1620A) in the tyrosine kinase domain. The occurrence of a cloverleaf skull deformity appears to represent an example of variable expressivity in hypochondroplasia and suggests that additional factors other than a specific mutation can modify the phenotype in this disorder. In addition, identification of another FGFR mutation associated with cloverleaf skull further illustrates the genetic heterogeneity of this anomaly. PMID:9842995

  13. Skulls and Human Evolution: The Use of Casts of Anthropoid Skulls in Teaching Concepts of Human Evolution.

    ERIC Educational Resources Information Center

    Gipps, John

    1991-01-01

    Proposes the use of a series of 11 casts of fossil skulls as a method of teaching about the theory of human evolution. Students explore the questions of which skulls are "human" and which came first in Homo Sapien development, large brain or upright stance. (MDH)

  14. The spectrum of facial fractures in motor vehicle accidents: an MDCT study of 374 patients.

    PubMed

    Peltola, Elina M; Koivikko, Mika P; Koskinen, Seppo K

    2014-04-01

    Road traffic accidents are a major health problem worldwide resulting frequently in maxillofacial injuries. The purpose of the study was to assess the incidence and spectrum of facial fractures in patients involved in a motor vehicle accident (MVA). Using picture archiving and communication system, all requests for suspected facial trauma were retrieved during a 62-month period; 374 met the inclusion criteria. Two researchers interpreted the multidetector computed tomography images by consensus. The motor vehicles involved were divided into two groups: those involving a passenger car or a larger vehicle and those involving a motorized two-wheeler. Furthermore, the motor vehicle accidents were divided into collisions and run-off-road accidents. Of the 374 patients (aged 15-80, mean 34), 271 (72 %) were male and 103 (28 %) female. Of all patients, 262 (70 %) had a facial or skull base fracture; of these, multiple separate fractures were present in 56 %. Nasal fractures were the most common fractures followed by orbital, skull base, and maxillary fractures. Frontal bone, LeFort, and zygomatic arch fractures were always accompanied by other fractures. Fractures were more frequent in the group of collisions compared with run-off-road accidents. In the two-wheeled group, only 15 % did not have facial or skull base fractures. Fractures often occur in multitudes as 39 % of all patients have multiple facial or skull bone fractures, and thus, emergency radiologists should be familiar with the complexity of the injuries. Negative clear sinus sign and low-energy sentinel injuries should be trusted as indications of undetected injuries in MVA victims. PMID:24221020

  15. Frontal Sinus Fractures: Current Concepts

    PubMed Central

    Strong, E. Bradley

    2009-01-01

    Frontal sinus injuries may range from isolated anterior table fractures resulting in a simple aesthetic deformity to complex fractures involving the frontal recess, orbits, skull base, and intracranial contents. The risk of long-term morbidity can be significant. Optimal treatment strategies for the management of frontal sinus fractures remain controversial. However, it is critical to have a thorough understanding of frontal sinus anatomy as well as the current treatment strategies used to manage these injuries. A thorough physical exam and thin-cut, multiplanar (axial, coronal, and sagittal) computed tomography scan should be performed in all patients suspected of having a frontal sinus fracture. The most appropriate treatment strategy can be determined by assessing five anatomic parameters including the: frontal recess, anterior table integrity, posterior table integrity, dural integrity, and presence of a cerebrospinal fluid leak. A well thought out management strategy and meticulous surgical techniques are critical to success. The primary surgical goal is to provide a safe sinus while minimizing patient morbidity. This article offers an anatomically based treatment algorithm for the management of frontal sinus fractures and highlights the key steps to surgical repair. PMID:22110810

  16. Reconstruction of Rare Skull Metastases Using Free Latissimus Dorsi Flap and the Role of Preoperative Embolization in Hypervascular Skull Tumors.

    PubMed

    Singh, Mansher; Ricci, Joseph A; Talbot, Simon G; Chiocca, E Antonio; Dunn, Ian F; Caterson, Edward J

    2015-11-01

    Metastatic tumors are the most common cranial neoplasms in adults. Skull metastases from rare primary tumors, such as cholangiocarcinoma or pancreatic neuroendocrine tumor, are extremely uncommon and rarely reported. Given the scarcity and variation of these rare skull metastases, treatments and outcomes of such patients are of interest to treating surgeons. The authors describe the treatment algorithm, course, and outcomes of 2 patients with rare gastrointestinal skull metastases. The first patient had intrahepatic cholangiocarcinoma metastatic to the skull, while the second patient developed a solitary skull metastasis secondary to a pancreatic neuroendocrine tumor. As part of this report, the authors include a literature review of rare skull metastases as well as the treatment of these 2 patients. Both the patients ultimately underwent successful resection of the tumor for relief of their clinical symptoms. Wide resections in both patients necessitated reconstruction using a free latissimus dorsi muscle flap in both the patients. Preoperative embolization of the hypervascular cholangiocarcinoma skull metastasis was performed prior to resection in the first patient. To date, there have been only 4 such reports of skull metastases from intrahepatic cholangiocarcinoma and limited reported cases of isolated skull metastases from a pancreatic neuroendocrine tumor.In patients with large or numerous skull metastasis from rare primary tumors, surgical resection should be considered for symptomatic improvement. In cases of hypervascular lesions, preoperative embolization can be considered to decrease the intraoperative bleeding. Free tissue transfers using myocutaneous flaps such as latissimus dorsi help in obliterating dead space, and creating a healthy soft tissue envelope to withstand postoperative radiation treatment. In addition, a chimeric flap can be designed to include additional muscle or soft tissue to obliterate and exclude the sinus cavities.

  17. Transnasal endoscopy-assisted skull base surgery.

    PubMed

    Stamm, Aldo M

    2006-09-01

    Skull base surgery (SBS), which originated in the 19th century, became refined in the 20th century in parallel with technological advancements and is now in the midst of further refinements largely driven by advances in endoscopic sinus surgery. With the development of modern SBS, lesions that were once inoperable and potentially fatal can now be eradicated successfully by means of endoscopy-assisted procedures that reduce or completely eliminate intracranial trauma, minimize postsurgical morbidity, and make full recovery possible. It is absolutely mandatory to have the appropriate instrumentation for endoscopy-assisted SBS. Among the new technologies available are advanced endoscopes, high-speed suction irrigation drills, digital video cameras, computed tomography and magnetic resonance imaging, and systems for 3-dimensional computer-assisted image-guided surgical navigation. An experienced endoscopic surgeon working with multidisciplinary teams, and using new instrumentation and techniques, can bring SBS to new levels of success in the 21st century. PMID:17040018

  18. Osteomyelitis of the base of the skull

    SciTech Connect

    Chandler, J.R.; Grobman, L.; Quencer, R.; Serafini, A.

    1986-03-01

    Infection in the marrow of the temporal, occipital, and sphenoid bones is an uncommon, but increasing occurrence. It is usually secondary to infections beginning in the external auditory canal and is caused almost uniformly by the gram negative Pseudomonas aeruginosa bacteria. Technetium and gallium scintigraphy help in the early detection of such infections while CT scans demonstrate dissolution of bone in well-developed cases. Headache is the predominant symptom. Dysphagia, hoarseness, and aspiration herald the inevitable march of cranial nerves. We have diagnosed and treated 17 cases of osteomyelitis of the skull base. Although the total mortality rate is 53%, it is now a curable disease. Six of our last 8 patients remain alive, although 1 is still under treatment. Treatment is medical and requires the long-term concomitant intravenous administration of an aminoglycoside and a broad spectrum semisynthetic penicillin effective against the causative organism.

  19. History of endonasal skull base surgery.

    PubMed

    Wang, Amy J; Zaidi, Hasan A; Laws, Edward D

    2016-12-01

    While the endonasal approach to the skull base continues to advance, this paper invokes its long history. The centuries of medieval neuroanatomy and early neurosurgery enabled the conception of the first transfacial approaches in the late 1800s; Henry Schloffer performed the first transsphenoidal surgery in 1907. Although the procedure was initially met with much interest, Harvey Cushing eventually led the field of neurosurgery to abandon the transsphenoidal approach in the 1920s. The following three generations of neurosurgeons contained several key figures including Norman Dott, Gerard Guiot, and Jules Hardy who were steadfast in preserving the technique as well as in addressing its shortcomings. The endoscopic approach developed simultaneously, and advances in magnifying and fiberoptics further resolved limitations previously inherent to the transsphenoidal approach. At last, in the 1960s, the transsphenoidal approach entered its renaissance. Today, the momentum of its development persists in the endoscopic endonasal approach, which has recently expanded the indications for transsphenoidal surgery across the skull base, far beyond its original jurisdiction of the sella. Continued progress must not take for granted the rich history of the transsphenoidal approach, which was developed over centuries by surgeons around the world. The authors present the evolution of modern endonasal surgery as a dynamic interplay between technology, medicine, and surgery over the past 100 years. Progress can be attributed to courageous surgeons who affirmed their contemporary practices despite gaps in technology or medicine, and to visionary individuals who produced and incorporated new elements into transsphenoidal surgery. And so while the new endoscopic technique brings forth new challenges, its development reaffirms the principles laid down by the pioneers of transsphenoidal surgery. PMID:27273318

  20. The transnasal approach to the skull base. From sinus surgery to skull base surgery

    PubMed Central

    Wagenmann, Martin; Schipper, Jörg

    2012-01-01

    The indications for endonasal endoscopic approaches to diseases of the skull base and its adjacent structures have expanded considerably during the last decades. This is not only due to improved technical possibilities such as intraoperative navigation, the development of specialized instruments, and the compilation of anatomical studies from the endoscopic perspective but also related to the accumulating experience with endoscopic procedures of the skull base by multidisciplinary centers. Endoscopic endonasal operations permit new approaches to deeply seated lesions and are characterized by a reduced manipulation of neurovascular structures and brain parenchyma while at the same time providing improved visualization. They reduce the trauma caused by the approach, avoid skin incisions and minimize the surgical morbidity. Transnasal endoscopic procedures for the closure of small and large skull base defects have proven to be reliable and more successful than operations with craniotomies. The development of new local and regional vascularized flaps like the Hadad-flap have contributed to this. These reconstructive techniques are furthermore effectively utilized in tumor surgery in this region. This review delineates the classification of expanded endonasal approaches in detail. They provide access to lesions of the anterior, middle and partly also to the posterior cranial fossa. Successful management of these complex procedures requires a close interdisciplinary collaboration as well as continuous education and training of all team members. PMID:22558058

  1. Geologic map of the Skull Creek Quadrangle, Moffat County Colorado

    USGS Publications Warehouse

    Van Loenen, R. E.; Selner, Gary; Bryant, W.A.

    1999-01-01

    The Skull Creek quadrangle is in northwestern Colorado a few miles north of Rangely. The prominent structural feature of the Skull Creek quadrangle is the Skull Creek monocline. Pennsylvanian rocks are exposed along the axis of the monocline while hogbacks along its southern flank expose rocks that are from Permian to Upper Cretaceous in age. The Wolf Creek monocline and the Wolf Creek thrust fault, which dissects the monocline, are salient structural features in the northern part of the quadrangle. Little or no mineral potential exists within the quadrangle. A geologic map of the Lazy Y Point quadrangle, which is adjacent to the Skull Creek quadrangle on the west, is also available (Geologic Investigations Series I-2646). This companian map shows similar geologic features, including the western half of the Skull Creek monocline. The geology of this quadrangle was mapped because of its proximity to Dinosaur National Monument. It is adjacent to quadrangles previously mapped to display the geology of this very scenic and popular National Monument. The Skull Creek quadrangle includes parts of the Skull Creek Wilderness Study Area, which was assessed for its mineral resource potential.

  2. Skull invaders: when surgical pathology and neuropathology worlds collide.

    PubMed

    Serracino, Hilary S; Kleinschmidt-Demasters, B K

    2013-07-01

    Skull and dura serve as effective barriers to penetration by most tumors, often preventing masses originating intracranially from extending into the contiguous bone and soft tissues, or those arising in head and neck regions from extending into the dura and brain tissue. We review our 15-year experience with extracranial tumors that had sufficiently invaded adjacent skull, dura, or brain from the "outside-in" to require a neurosurgeon to participate in the surgical resection and discuss our 40 cases in context with the literature. Sinonasal-origin tumors (n = 17) and cutaneous tumors (n = 10) were the most frequent skull-invaders. Most of the cutaneous tumor types were squamous cellcarcinomas (n = 9); diverse sinonasal-origin types included 4 squamous cell carcinomas, 4 adenoid cystic carcinomas, 2 sinonasal undifferentiated carcinomas, 2 sinonasal adenocarcinomas, and single examples each of sinonasal-origin hemangiopericytoma, solitary fibrous tumor, melanoma, mucocele, and teratocarcinoma. There were 9olfactory neuroblastomas, and middle ear-origin basal cell carcinoma,recurrent glomus jugulare, and orbital malignant hidradenoma were also seen. Unique tumors included a cutaneous cylindroma invasive of skull convexity occurring in familial cylindromatosis and a ganglioneuroma of the middle ear with massive bilateral skull base extension. Convexity dural spread, a seldom-reported pattern of dissemination, was seen in 1 olfactory neuroblastoma and 1 adenoid cystic carcinoma. The ability to show skull/dural invasion did not correlate with specific histopathologic features; even benign tumor types can show skull/dural penetration.

  3. Computer-assisted skull identification system using video superimposition.

    PubMed

    Yoshino, M; Matsuda, H; Kubota, S; Imaizumi, K; Miyasaka, S; Seta, S

    1997-12-01

    This system consists of two main units, namely a video superimposition system and a computer-assisted skull identification system. The video superimposition system is comprised of the following five parts: a skull-positioning box having a monochrome CCD camera, a photo-stand having a color CCD camera, a video image mixing device, a TV monitor and a videotape recorder. The computer-assisted skull identification system is composed of a host computer including our original application software, a film recorder and a color printer. After the determination of the orientation and size of the skull to those of the facial photograph using the video superimposition system, the skull and facial photograph images are digitized and stored within the computer, and then both digitized images are superimposed on the monitor. For the assessment of anatomical consistency between the digitized skull and face, the distance between the landmarks and the thickness of soft tissue of the anthropometrical points are semi-automatically measured on the monitor. The wipe images facilitates the comparison of positional relationships between the digitized skull and face. The software includes the polynomial functions and Fourier harmonic analysis for evaluating the match of the outline such as the forehead and mandibular line in both the digitized images.

  4. Trans-skull ultrasonic Doppler system aided by fuzzy logic

    NASA Astrophysics Data System (ADS)

    Hata, Yutaka; Nakamura, Masato; Yagi, Naomi; Ishikawa, Tomomoto

    2012-06-01

    This paper describes a trans-skull ultrasonic Doppler system for measuring the blood flow direction in brain under skull. In this system, we use an ultrasonic array probe with the center frequency of 1.0 MHz. The system determines the fuzzy degree of blood flow by Doppler Effect, thereby it locates blood vessel. This Doppler Effect is examined by the center of gravity shift of the frequency magnitudes. In in-vitro experiment, a cow bone was employed as the skull, and three silicon tubes were done as blood vessels, and bubble in water as blood. We received the ultrasonic waves through a protein, the skull and silicon tubes in order. In the system, fuzzy degrees are determined with respect to the Doppler shift, amplitude of the waves and attenuation of the tissues. The fuzzy degrees of bone and blood direction are calculated by them. The experimental results showed that the system successfully visualized the skull and flow direction, compared with the location and flow direction of the phantom. Thus, it detected the flow direction by Doppler Effect under skull, and automatically extracted the region of skull and blood vessel.

  5. Advances in Magnetic Resonance Imaging of the Skull Base

    PubMed Central

    Kirsch, Claudia F.E.

    2014-01-01

    Introduction Over the past 20 years, magnetic resonance imaging (MRI) has advanced due to new techniques involving increased magnetic field strength and developments in coils and pulse sequences. These advances allow increased opportunity to delineate the complex skull base anatomy and may guide the diagnosis and treatment of the myriad of pathologies that can affect the skull base. Objectives The objective of this article is to provide a brief background of the development of MRI and illustrate advances in skull base imaging, including techniques that allow improved conspicuity, characterization, and correlative physiologic assessment of skull base pathologies. Data Synthesis Specific radiographic illustrations of increased skull base conspicuity including the lower cranial nerves, vessels, foramina, cerebrospinal fluid (CSF) leaks, and effacement of endolymph are provided. In addition, MRIs demonstrating characterization of skull base lesions, such as recurrent cholesteatoma versus granulation tissue or abscess versus tumor, are also provided as well as correlative clinical findings in CSF flow studies in a patient pre- and post-suboccipital decompression for a Chiari I malformation. Conclusions This article illustrates MRI radiographic advances over the past 20 years, which have improved clinicians' ability to diagnose, define, and hopefully improve the treatment and outcomes of patients with underlying skull base pathologies. PMID:25992137

  6. Influence of skull modeling approaches on EEG source localization.

    PubMed

    Montes-Restrepo, Victoria; van Mierlo, Pieter; Strobbe, Gregor; Staelens, Steven; Vandenberghe, Stefaan; Hallez, Hans

    2014-01-01

    Electroencephalographic source localization (ESL) relies on an accurate model representing the human head for the computation of the forward solution. In this head model, the skull is of utmost importance due to its complex geometry and low conductivity compared to the other tissues inside the head. We investigated the influence of using different skull modeling approaches on ESL. These approaches, consisting in skull conductivity and geometry modeling simplifications, make use of X-ray computed tomography (CT) and magnetic resonance (MR) images to generate seven different head models. A head model with an accurately segmented skull from CT images, including spongy and compact bone compartments as well as some air-filled cavities, was used as the reference model. EEG simulations were performed for a configuration of 32 and 128 electrodes, and for both noiseless and noisy data. The results show that skull geometry simplifications have a larger effect on ESL than those of the conductivity modeling. This suggests that accurate skull modeling is important in order to achieve reliable results for ESL that are useful in a clinical environment. We recommend the following guidelines to be taken into account for skull modeling in the generation of subject-specific head models: (i) If CT images are available, i.e., if the geometry of the skull and its different tissue types can be accurately segmented, the conductivity should be modeled as isotropic heterogeneous. The spongy bone might be segmented as an erosion of the compact bone; (ii) when only MR images are available, the skull base should be represented as accurately as possible and the conductivity can be modeled as isotropic heterogeneous, segmenting the spongy bone directly from the MR image; (iii) a large number of EEG electrodes should be used to obtain high spatial sampling, which reduces the localization errors at realistic noise levels.

  7. The MDP skull uptake test: A new diagnostic tool

    SciTech Connect

    Ell, P.J.; Jarritt, P.H.; Cullum, I.; Lui, D.

    1984-01-01

    An original approach to the measurement of bone turnover is presented. With SPECT, the authors have measured in pgr/ml, the uptake of MDP by the skull in man. The Cleon 710 scanner, ring phantoms and bone biopsies were used for ultimate in vivo/in vitro count recovery correlation and calibration. A normal range for 24 patients was found: 8.5 to 19.5 pgr/ml with a mean of 14. For patients with bony metastases (12), the values were: 22.5 to 50, mean of 30. For 5 patients with osteomalacia, the values were 46 to 68, mean of 62: for 12 patients with hyperparathyroidism, the values were 37 to 48.5, mean of 43. In 3 patients with Pagets disease, the values were 58.5 to 75, with a mean of 65. In 76 patients with metastatic disease to bone, the conventional wholebody bone scan was investigated against the following: 24h wholebody retention of MDP (WBR), skull uptake as described and GFR by Cr-51-DTPA. There is a correlation between GFR and WBR - r=0.67. There is a lesser correlation between GFR and skull uptake - r=0.3. There is no correlation between skull uptake and WBR - r=0.1. The comparison of skull uptake data with normal whole body bone scans leads to a significant proportion of cancer patients with positive skull uptake data. Monostotic disease (especially if metabolic in nature) expresses itself by abnormal skull uptake even if the clinical site of abnormality lies outside the skull. This new technique is ideal as a tool to investigate phosphonate concentration in bone. With it, the authors have shown the effect of specific activity of label on skull uptake, which increases as the specific activity of labelled MDP decreases.

  8. Hand in glove: brain and skull in development and dysmorphogenesis.

    PubMed

    Richtsmeier, Joan T; Flaherty, Kevin

    2013-04-01

    The brain originates relatively early in development from differentiated ectoderm that forms a hollow tube and takes on an exceedingly complex shape with development. The skull is made up of individual bony elements that form from neural crest- and mesoderm-derived mesenchyme that unite to provide support and protection for soft tissues and spaces of the head. The meninges provide a protective and permeable membrane between brain and skull. Across evolutionary and developmental time, dynamic changes in brain and skull shape track one another so that their integration is evidenced in two structures that fit soundly regardless of changes in biomechanical and physiologic functions. Evidence for this tight correspondence is also seen in diseases of the craniofacial complex that are often classified as diseases of the skull (e.g., craniosynostosis) or diseases of the brain (e.g., holoprosencephaly) even when both tissues are affected. Our review suggests a model that links brain and skull morphogenesis through coordinated integration of signaling pathways (e.g., FGF, TGFβ, Wnt) via processes that are not currently understood, perhaps involving the meninges. Differences in the earliest signaling of biological structure establish divergent designs that will be enhanced during morphogenesis. Signaling systems that pattern the developing brain are also active in patterning required for growth and assembly of the skull and some members of these signaling families have been indicated as causal for craniofacial diseases. Because cells of early brain and skull are sensitive to similar signaling families, variation in the strength or timing of signals or shifts in patterning boundaries that affect one system (neural or skull) could also affect the other system and appropriate co-adjustments in development would be made. Interactions of these signaling systems and of the tissues that they pattern are fundamental to the consistent but labile functional and structural association

  9. New insights into the skull of Istiodactylus latidens (Ornithocheiroidea, Pterodactyloidea).

    PubMed

    Witton, Mark P

    2012-01-01

    The skull of the Cretaceous pterosaur Istiodactylus latidens, a historically important species best known for its broad muzzle of interlocking, lancet-shaped teeth, is almost completely known from the broken remains of several individuals, but the length of its jaws remains elusive. Estimates of I. latidens jaw length have been exclusively based on the incomplete skull of NHMUK R3877 and, perhaps erroneously, reconstructed by assuming continuation of its broken skull pieces as preserved in situ. Here, an overlooked jaw fragment of NHMUK R3877 is redescribed and used to revise the skull reconstruction of I. latidens. The new reconstruction suggests a much shorter skull than previously supposed, along with a relatively tall orbital region and proportionally slender maxilla, a feature documented in the early 20(th) century but ignored by all skull reconstructions of this species. These features indicate that the skull of I. latidens is particularly distinctive amongst istiodactylids and suggests greater disparity between I. latidens and I. sinensis than previously appreciated. A cladistic analysis of istiodactylid pterosaurs incorporating new predicted I. latidens skull metrics suggests Istiodactylidae is constrained to five species (Liaoxipterus brachyognathus, Lonchengpterus zhoai, Nurhachius ignaciobritoi, Istiodactylus latidens and Istiodactylus sinensis) defined by their distinctive dentition, but excludes the putative istiodactylids Haopterus gracilis and Hongshanopterus lacustris. Istiodactylus latidens, I. sinensis and Li. brachyognathus form an unresolved clade of derived istiodactylids, and the similarity of comparable remains of I. sinensis and Li. brachyognathus suggest further work into their taxonomy and classification is required. The new skull model of I. latidens agrees with the scavenging habits proposed for these pterosaurs, with much of their cranial anatomy converging on that of habitually scavenging birds.

  10. Hand in glove: brain and skull in development and dysmorphogenesis

    PubMed Central

    Flaherty, Kevin

    2013-01-01

    The brain originates relatively early in development from differentiated ectoderm that forms a hollow tube and takes on an exceedingly complex shape with development. The skull is made up of individual bony elements that form from neural crest- and mesoderm-derived mesenchyme that unite to provide support and protection for soft tissues and spaces of the head. The meninges provide a protective and permeable membrane between brain and skull. Across evolutionary and developmental time, dynamic changes in brain and skull shape track one another so that their integration is evidenced in two structures that fit soundly regardless of changes in biomechanical and physiologic functions. Evidence for this tight correspondence is also seen in diseases of the craniofacial complex that are often classified as diseases of the skull (e.g., craniosynostosis) or diseases of the brain (e.g., holoprosencephaly) even when both tissues are affected. Our review suggests a model that links brain and skull morphogenesis through coordinated integration of signaling pathways (e.g., FGF, TGFβ, Wnt) via processes that are not currently understood, perhaps involving the meninges. Differences in the earliest signaling of biological structure establish divergent designs that will be enhanced during morphogenesis. Signaling systems that pattern the developing brain are also active in patterning required for growth and assembly of the skull and some members of these signaling families have been indicated as causal for craniofacial diseases. Because cells of early brain and skull are sensitive to similar signaling families, variation in the strength or timing of signals or shifts in patterning boundaries that affect one system (neural or skull) could also affect the other system and appropriate co-adjustments in development would be made. Interactions of these signaling systems and of the tissues that they pattern are fundamental to the consistent but labile functional and structural association

  11. New Insights into the Skull of Istiodactylus latidens (Ornithocheiroidea, Pterodactyloidea)

    PubMed Central

    Witton, Mark P.

    2012-01-01

    The skull of the Cretaceous pterosaur Istiodactylus latidens, a historically important species best known for its broad muzzle of interlocking, lancet-shaped teeth, is almost completely known from the broken remains of several individuals, but the length of its jaws remains elusive. Estimates of I. latidens jaw length have been exclusively based on the incomplete skull of NHMUK R3877 and, perhaps erroneously, reconstructed by assuming continuation of its broken skull pieces as preserved in situ. Here, an overlooked jaw fragment of NHMUK R3877 is redescribed and used to revise the skull reconstruction of I. latidens. The new reconstruction suggests a much shorter skull than previously supposed, along with a relatively tall orbital region and proportionally slender maxilla, a feature documented in the early 20th century but ignored by all skull reconstructions of this species. These features indicate that the skull of I. latidens is particularly distinctive amongst istiodactylids and suggests greater disparity between I. latidens and I. sinensis than previously appreciated. A cladistic analysis of istiodactylid pterosaurs incorporating new predicted I. latidens skull metrics suggests Istiodactylidae is constrained to five species (Liaoxipterus brachyognathus, Lonchengpterus zhoai, Nurhachius ignaciobritoi, Istiodactylus latidens and Istiodactylus sinensis) defined by their distinctive dentition, but excludes the putative istiodactylids Haopterus gracilis and Hongshanopterus lacustris. Istiodactylus latidens, I. sinensis and Li. brachyognathus form an unresolved clade of derived istiodactylids, and the similarity of comparable remains of I. sinensis and Li. brachyognathus suggest further work into their taxonomy and classification is required. The new skull model of I. latidens agrees with the scavenging habits proposed for these pterosaurs, with much of their cranial anatomy converging on that of habitually scavenging birds. PMID:22470442

  12. Development of a neonatal skull phantom for photoacoustic imaging

    NASA Astrophysics Data System (ADS)

    Tavakolian, Pantea; Todd, Rhiannon; Kosik, Ivan; Chamson-Reig, Astrid; Vasefi, Fartash; St. Lawrence, Keith; Carson, Jeffrey J. L.

    2013-03-01

    Photoacoustic imaging (PAI) has been proposed as a non-invasive technique for the diagnosis and monitoring of disorders in the neonatal brain. However, PAI of the brain through the intact skull is challenging due to reflection and attenuation of photoacoustic pressure waves by the skull bone. The objective of this work was to develop a phantom for testing the potential limits the skull bone places on PAI of the neonatal brain. Our approach was to make acoustic measurements on materials designed to mimic the neonatal skull bone and construct a semi-realistic phantom. A water tank and two ultrasound transducers were utilized to measure the ultrasound insertion loss (100 kHz to 5MHz) of several materials. Cured mixtures of epoxy and titanium dioxide powder provided the closest acoustic match to neonatal skull bone. Specifically, a 1.4-mm thick sample composed of 50% (by mass) titanium dioxide powder and 50% epoxy was closest to neonatal skull bone in terms of acoustic insertion loss. A hemispherical skull phantom (1.4 mm skull thickness) was made by curing the epoxy/titanium dioxide powder mixture inside a mold. The mold was constructed using 3D prototyping techniques and was based on the hairless head of a realistic infant doll. The head was scanned to generate a 3D model, which in turn was used to build a 3D CAD version of the mold. The mold was CNC machined from two solid blocks of Teflon®. The neonatal skull phantom will enable the study of the propagation of photoacoustic pressure waves under a variety of experimental conditions.

  13. AN UNUSUAL PRESENTATION OF HUGE MENINGIOMA EXTRUDING OUT OF SKULL.

    PubMed

    Rafiq, Mirza Faisal Ahmed; Khaleeq-uz-Zaman; Ibrahima, Muhammad

    2016-01-01

    Scalp masses are commonly seen in clinical practice. They range from simple sebaceous cyst to malignant neoplasms. Clinical presentation is straight forward in most of the cases. Simple subcutaneous swelling till erosion of scalp and skull all can occur. However very few intracranial masses present with exophytic scalp swelling. This is because they have to erode dura, thick skull bone and all the layers of scalp to appear out on scalp. It is very unusual that an intracranial mass present like a scalp swelling. Some of the intracranial masses have tendency to erode skull. Dermoid & meningioma are among the most common. PMID:27323599

  14. Imaging in Endoscopic Cranial Skull Base and Pituitary Surgery.

    PubMed

    Nunes, Renato Hoffmann; Abello, Ana Lorena; Zanation, Adam M; Sasaki-Adams, Deanna; Huang, Benjamin Y

    2016-02-01

    Endoscopic endonasal approaches have widely accepted techniques for managing benign and malignant processes along the entire ventral skull base with similar or better results compared with open procedures, but with lower rates of complication. Managing pathology affecting the skull base can be challenging because of complex anatomy and the proximity of critical neurovascular structures. Postoperative imaging can be challenging, because of surgical alterations of normal anatomy and the now common use of complex reconstruction techniques. Understanding the normal imaging appearance of skull base reconstruction is important for accurate postoperative interpretation and delineation between normal reconstructive tissue and recurrent neoplasm.

  15. Cancers of the nose, sinus, and skull base.

    PubMed

    Banuchi, Victoria; Mallen, Jonathan; Kraus, Dennis

    2015-07-01

    Malignancies of the nose, sinus, and skull base are rare. The most common histologies are squamous cell carcinoma and adenocarcinoma. The most common primary sites are the nasal cavity and maxillary sinus. Management of these tumors is technically challenging because they often present in advanced stages with extensive disease invading important structures such as the orbit and the skull base. In the last few decades advances in surgical resection techniques, as well as improved strategies to deliver adjuvant radiation, have substantially improved the outcomes in patients with malignancies of the sinonasal tract and skull base. PMID:25979400

  16. Elemental analysis of cetacean skull lesions associated with nematode infections.

    PubMed

    Pascual, S; Abollo, E; López, A

    2000-08-10

    The elemental composition of both healthy and eroded cetacean skulls associated with nematode infections was evaluated. A total of 27 samples of eroded and non-eroded prepared museum cetacean skulls were characterised by elemental (CHN), X-ray fluorescence, and X-ray diffraction methods. The inorganic composition and crystal line structure (hydroxylapatite-like minerals) were similar for both types of skull samples, but the CHN values clearly differed. The results suggest that the carbon-rich fraction is lost in eroded areas, probably as a result of glycosaminoglycan-degrading Crassicauda enzymes.

  17. Elbow Fractures

    MedlinePlus

    ... and held together with pins and wires or plates and screws. Fractures of the distal humerus (see ... doctor. These fractures usually require surgical repair with plates and/or screw, unless they are stable. SIGNS ...

  18. Facial fractures.

    PubMed Central

    Carr, M. M.; Freiberg, A.; Martin, R. D.

    1994-01-01

    Emergency room physicians frequently see facial fractures that can have serious consequences for patients if mismanaged. This article reviews the signs, symptoms, imaging techniques, and general modes of treatment of common facial fractures. It focuses on fractures of the mandible, zygomaticomaxillary region, orbital floor, and nose. Images p520-a p522-a PMID:8199509

  19. Skull base, orbits, temporal bone, and cranial nerves: anatomy on MR imaging.

    PubMed

    Morani, Ajaykumar C; Ramani, Nisha S; Wesolowski, Jeffrey R

    2011-08-01

    Accurate delineation, diagnosis, and treatment planning of skull base lesions require knowledge of the complex anatomy of the skull base. Because the skull base cannot be directly evaluated, imaging is critical for the diagnosis and management of skull base diseases. Although computed tomography (CT) is excellent for outlining the bony detail, magnetic resonance (MR) imaging provides better soft tissue detail and is helpful for evaluating the adjacent meninges, brain parenchyma, and bone marrow of the skull base. Thus, CT and MR imaging are often used together for evaluating skull base lesions. This article focuses on the radiologic anatomy of the skull base pertinent to MR imaging evaluation.

  20. Pediatric Orbital Fractures

    PubMed Central

    Oppenheimer, Adam J.; Monson, Laura A.; Buchman, Steven R.

    2013-01-01

    It is wise to recall the dictum “children are not small adults” when managing pediatric orbital fractures. In a child, the craniofacial skeleton undergoes significant changes in size, shape, and proportion as it grows into maturity. Accordingly, the craniomaxillofacial surgeon must select an appropriate treatment strategy that considers both the nature of the injury and the child's stage of growth. The following review will discuss the management of pediatric orbital fractures, with an emphasis on clinically oriented anatomy and development. PMID:24436730

  1. A direct measurement of skull attenuation for quantitative SPECT

    SciTech Connect

    Turkington, T.G.; Gilland, D.R.; Jaszczak, R.J.; Greer, K.L.; Coleman, R.E. . Dept. of Radiology); Smith, M.F. . Dept. of Biomedical Engineering)

    1993-08-01

    The attenuation of 140 keV photons was measured in three empty skulls by placing a [sup 99m]Tc line source inside each one and acquiring projection data. These projections were compared to projections of the line source alone to determine the transmission through each point in the skull surrounding the line source. The effective skull thickness was calculated for each point using an assumed dense bone attenuation coefficient. The relative attenuation for this thickness of bone was compared to that of an equivalent amount of soft tissue to evaluate the increased attenuation of photons in brain SPECT relative to a uniform soft tissue approximation. For the skull regions surrounding most of the brain, the effective bone thickness varied considerably, but was generally less than 6 mm, resulting in a relative attenuation increases of less than 6%.

  2. Effects of the murine skull in optoacoustic brain microscopy.

    PubMed

    Kneipp, Moritz; Turner, Jake; Estrada, Héctor; Rebling, Johannes; Shoham, Shy; Razansky, Daniel

    2016-01-01

    Despite the great promise behind the recent introduction of optoacoustic technology into the arsenal of small-animal neuroimaging methods, a variety of acoustic and light-related effects introduced by adult murine skull severely compromise the performance of optoacoustics in transcranial imaging. As a result, high-resolution noninvasive optoacoustic microscopy studies are still limited to a thin layer of pial microvasculature, which can be effectively resolved by tight focusing of the excitation light. We examined a range of distortions introduced by an adult murine skull in transcranial optoacoustic imaging under both acoustically- and optically-determined resolution scenarios. It is shown that strong low-pass filtering characteristics of the skull may significantly deteriorate the achievable spatial resolution in deep brain imaging where no light focusing is possible. While only brain vasculature with a diameter larger than 60 µm was effectively resolved via transcranial measurements with acoustic resolution, significant improvements are seen through cranial windows and thinned skull experiments.

  3. Lung cancer metastasis presenting as a solitary skull mass

    PubMed Central

    Turner, Ryan C.; Lucke-Wold, Brandon P.; Hwang, Roy; Underwood, Bill D.

    2016-01-01

    Lung cancer has been well documented to spread to bone and the axial skeleton after metastasis to adjacent organs. Bony metastasis is not, however, the typical presenting manifestation. The differential diagnosis for a tissue mass on the skull should warrant a workup for metastatic disease. Bony metastasis plays an important role in treatment and disease management. We report an exceptionally rare case of stage IV lung adenocarcinoma that presented with a solitary skull metastasis and a significant soft-tissue component. The lesion was treated by excision via craniotomy and subsequent medical management of the adenocarcinoma. This case illustrates a very rare presentation of lung adenocarcinoma and also represents what the authors believe to be the first report of a solitary skull mass originating from a lung primary. We also present a review of the literature surrounding bony metastasis to the skull and implications for patient care. PMID:27340229

  4. Lung cancer metastasis presenting as a solitary skull mass.

    PubMed

    Turner, Ryan C; Lucke-Wold, Brandon P; Hwang, Roy; Underwood, Bill D

    2016-01-01

    Lung cancer has been well documented to spread to bone and the axial skeleton after metastasis to adjacent organs. Bony metastasis is not, however, the typical presenting manifestation. The differential diagnosis for a tissue mass on the skull should warrant a workup for metastatic disease. Bony metastasis plays an important role in treatment and disease management. We report an exceptionally rare case of stage IV lung adenocarcinoma that presented with a solitary skull metastasis and a significant soft-tissue component. The lesion was treated by excision via craniotomy and subsequent medical management of the adenocarcinoma. This case illustrates a very rare presentation of lung adenocarcinoma and also represents what the authors believe to be the first report of a solitary skull mass originating from a lung primary. We also present a review of the literature surrounding bony metastasis to the skull and implications for patient care. PMID:27340229

  5. Minimally invasive surgery of the anterior skull base: transorbital approaches

    PubMed Central

    Gassner, Holger G.; Schwan, Franziska; Schebesch, Karl-Michael

    2016-01-01

    Minimally invasive approaches are becoming increasingly popular to access the anterior skull base. With interdisciplinary cooperation, in particular endonasal endoscopic approaches have seen an impressive expansion of indications over the past decades. The more recently described transorbital approaches represent minimally invasive alternatives with a differing spectrum of access corridors. The purpose of the present paper is to discuss transorbital approaches to the anterior skull base in the light of the current literature. The transorbital approaches allow excellent exposure of areas that are difficult to reach like the anterior and posterior wall of the frontal sinus; working angles may be more favorable and the paranasal sinus system can be preserved while exposing the skull base. Because of their minimal morbidity and the cosmetically excellent results, the transorbital approaches represent an important addition to established endonasal endoscopic and open approaches to the anterior skull base. Their execution requires an interdisciplinary team approach. PMID:27453759

  6. Nuclide angiography in Paget's disease of the skull: Case report.

    PubMed

    Fitzer, P M

    1975-07-01

    Early-appearing and persistent uptake on nuclear angiography in a patient with early Paget's disease of the skull is described. The diagnosis of subdural hematoma may be ruled out at the time of brain scanning. PMID:1167280

  7. Paul Broca's search for Basque skulls: The full story.

    PubMed

    Giménez-Roldán, Santiago

    2016-01-01

    Paul Broca surmised that the short and broad-brachycephalic-skulls of the earliest European settlers had become longer and narrower-dolichocephalic-in modern populations due to the blending of different races. Swedish anatomist Anders Retzius had two brachycephalic skulls said to be from contemporary Basque individuals, a claim suited to test Broca's hypothesis. Broca worked with fellow anatomist and surgeon Pedro González Velasco, the founding father of Spanish anthropology, to gather a large number of Basque skulls. In its time, this was the most fascinating collection owned by the Anthropological Society of Paris. This article explains how Broca and Velasco were able to gather such a sizeable array of specimens, which they had collected at a location known at first by the code name of "Z." Although Broca finally concluded that the origin of the Retzius skulls could not be determined, his research was to spark anthropologists' interest in the language and origins of the Basque people.

  8. Reliability of Craniofacial Superimposition Using Three-Dimension Skull Model.

    PubMed

    Gaudio, Daniel; Olivieri, Lara; De Angelis, Danilo; Poppa, Pasquale; Galassi, Andrea; Cattaneo, Cristina

    2016-01-01

    Craniofacial superimposition is a technique potentially useful for the identification of unidentified human remains if a photo of the missing person is available. We have tested the reliability of the 2D-3D computer-aided nonautomatic superimposition techniques. Three-dimension laser scans of five skulls and ten photographs were overlaid with an imaging software. The resulting superimpositions were evaluated using three methods: craniofacial landmarks, morphological features, and a combination of the two. A 3D model of each skull without its mandible was tested for superimposition; we also evaluated whether separating skulls by sex would increase correct identifications. Results show that the landmark method employing the entire skull is the more reliable one (5/5 correct identifications, 40% false positives [FP]), regardless of sex. However, the persistence of a high percentage of FP in all the methods evaluated indicates that these methods are unreliable for positive identification although the landmark-only method could be useful for exclusion.

  9. Foam-Driven Fractures of an Elastic Matrix

    NASA Astrophysics Data System (ADS)

    Lai, Ching-Yao; Smiddy, Sam; Stone, Howard

    2015-11-01

    We report an experimental study of foam-driven fractures in an elastic matrix. When a pressurized foam is constantly injected into a gelatin matrix with a constant flow rate, the foam generates a disc-like fracture which is commonly observed in liquid-driven fractures. Compare to liquid-driven fractures, foam-driven fractures grow faster with time. We investigate how the rheological behaviour of foams affects the fracture characteristics by varying the air volume fraction of the foam, the types and concentration of surfactants in the foam. Foam-fracturing reduces the environmental costs of hydraulic fracturing, which inspires this laboratory study.

  10. Pervasive genetic integration directs the evolution of human skull shape.

    PubMed

    Martínez-Abadías, Neus; Esparza, Mireia; Sjøvold, Torstein; González-José, Rolando; Santos, Mauro; Hernández, Miquel; Klingenberg, Christian Peter

    2012-04-01

    It has long been unclear whether the different derived cranial traits of modern humans evolved independently in response to separate selection pressures or whether they resulted from the inherent morphological integration throughout the skull. In a novel approach to this issue, we combine evolutionary quantitative genetics and geometric morphometrics to analyze genetic and phenotypic integration in human skull shape. We measured human skulls in the ossuary of Hallstatt (Austria), which offer a unique opportunity because they are associated with genealogical data. Our results indicate pronounced covariation of traits throughout the skull. Separate simulations of selection for localized shape changes corresponding to some of the principal derived characters of modern human skulls produced outcomes that were similar to each other and involved a joint response in all of these traits. The data for both genetic and phenotypic shape variation were not consistent with the hypothesis that the face, cranial base, and cranial vault are completely independent modules but relatively strongly integrated structures. These results indicate pervasive integration in the human skull and suggest a reinterpretation of the selective scenario for human evolution where the origin of any one of the derived characters may have facilitated the evolution of the others.

  11. A reconstruction of the Vienna skull of Hadropithecus stenognathus

    PubMed Central

    Ryan, T. M.; Burney, D. A.; Godfrey, L. R.; Göhlich, U. B.; Jungers, W. L.; Vasey, N.; Ramilisonina; Walker, A.; Weber, G. W.

    2008-01-01

    Franz Sikora found the first specimen and type of the recently extinct Hadropithecus stenognathus in Madagascar in 1899 and sent it to Ludwig Lorenz von Liburnau of the Austrian Imperial Academy of Sciences. Later, he sent several more specimens including a subadult skull that was described by Lorenz von Liburnau in 1902. In 2003, some of us excavated at the locality and found more specimens belonging to this species, including much of a subadult skeleton. Two frontal fragments were found, and these, together with most of the postcranial bones, belong to the skull. CT scans of the skull and other jaw fragments were made in Vienna and those of the frontal fragments at Penn State University. The two fragments have been reunited with the skull in silico, and broken parts from one side of the skull have been replaced virtually by mirror-imaged complete parts from the other side. The parts of the jaw of another individual of a slightly younger dental age have also been reconstructed virtually from CT scans with mirror imaging and by using the maxillary teeth and temporomandibular joints as a guide to finish the reconstruction. Apart from forming a virtual skull for biomechanical and systematic analysis, we were also able to make a virtual endocast. Missing anterior pieces were reconstructed by using part of an endocast of the related Archaeolemur majori. The volume is 115 ml. Hadropithecus and Archaeolemur seem to have had relatively large brains compared with the other large-bodied subfossil lemurs. PMID:18663217

  12. Meningiomas of the Pediatric Skull Base: A Review

    PubMed Central

    Gump, William C.

    2014-01-01

    Pediatric skull base meningiomas are rare and complex clinical entities. Meningioma is a relatively uncommon brain tumor in children, and only ∼ 27% involve the skull base. Some evidence suggests that these tumors are more likely to be atypical or malignant in children than adults. The absence of female preponderance in pediatric meningiomas is reflected in the skull base subpopulation. Skull base meningiomas in children are most likely to be found in the anterior or middle fossa base, or involving the orbit and optic nerve sheath. Petroclival, suprasellar/parasellar, cerebellopontine angle, cavernous sinus, and foramen magnum tumors are very rare. Meningiomas constitute a small proportion of reported cases of pediatric skull base pathology, and they are entirely absent from many case series. Initial gross total resection is consistently associated with superior outcomes. Surgical approaches to the pediatric skull base must take additional factors into consideration including relatively smaller anatomy, immature dentition, incompletely aerated sinuses and air cells, and altered configurations of structures such as the pterional bony complex. Multidisciplinary expertise is essential to optimizing treatment outcomes. PMID:25685652

  13. Metatarsal fractures.

    PubMed

    Rammelt, Stefan; Heineck, Jan; Zwipp, Hans

    2004-09-01

    Metatarsal fractures are relatively common and if malunited, a frequent source of pain and disability. Nondisplaced fractures and fractures of the second to fourth metatarsal with displacement in the horizontal plane can be treated conservatively with protected weight bearing in a cast shoe for 4-6 weeks. In most displaced fractures, closed reduction can be achieved but maintenance of the reduction needs internal fixation. Percutaneous pinning is suitable for most fractures of the lesser metatarsals. Fractures with joint involvement and multiple fragments frequently require open reduction and plate fixation. Transverse fractures at the metaphyseal-diaphyseal junction of the fifth metatarsal ("Jones fractures") require an individualized approach tailored to the level of activity and time to union. Avulsion fractures of the fifth metatarsal bone are treated by open reduction and tension-band wiring or screw fixation if displaced more than 2 mm or with more that 30% of the joint involved. The metatarsals are the most common site of stress fractures, most of which are treated nonoperatively. Symptomatic posttraumatic deformities need adequate correction, in most cases by osteotomy across the former fracture site.

  14. [Cloverleaf skull and other malformations of the skull. Pathology and clinical aspect].

    PubMed

    Gathmann, H A

    1977-01-01

    Malformations of different parts of the cartilage results in achondrogenesis II, thanatophoric dwarfism and in metatropic dwarfism. Whether the base of the skull or the cranial-distal skeleton are affected, both together or separately, depends upon the localization of the defect within the cartilage. The different types of the cloverleaf syndrome are characterised by a defect of vessels and cartilage that affect the chondrocranium and the cranial-distal skeleton in different grades. The mal-development of the vessel-system is particularly marked in the upper back of the calotte. PMID:610339

  15. Hemostasis in Endoscopic Endonasal Skull Base Surgery

    PubMed Central

    Vaz-Guimaraes, Francisco; Su, Shirley Y.; Fernandez-Miranda, Juan C.; Wang, Eric W.; Snyderman, Carl H.; Gardner, Paul A.

    2015-01-01

    William Halsted established the basic principles of modern surgical technique highlighting the importance of meticulous hemostasis and careful tissue handling. These concepts hold true today and are even more critical for endoscopic visualization, making hemostasis one of the most relevant cornerstones for the safe practice of endoscopic endonasal surgery (EES) of the skull base. During preoperative assessment, patients at higher risk for serious hemorrhagic complications must be recognized. From an anatomical point of view, EES can be grossly divided in two major components: sinonasal surgery and sellar-cranial base surgery. This division affects the choice of appropriate technique for control of bleeding that relies mainly on the source of hemorrhage, the tissue involved, and the proximity of critical neurovascular structures. Pistol-grip or single-shaft instruments constitute the most important and appropriately designed instruments available for EES. Electrocoagulation and a variety of hemostatic materials are also important tools and should be applied wisely. This article describes the experience of our team in the management of hemorrhagic events during EES with an emphasis on technical nuances. PMID:26225320

  16. Peramorphic traits in the tokay gecko skull.

    PubMed

    Daza, Juan D; Mapps, Aurelia A; Lewis, Patrick J; Thies, Monte L; Bauer, Aaron M

    2015-08-01

    Traditionally, geckos have been conceived to exhibit paedomorphic features relative to other lizards (e.g., large eyes, less extensively ossified skulls, and amphicoelous and notochordal vertebrae). In contrast, peramorphosis has not been considered an important process in shaping their morphology. Here, we studied different sized specimens of Gekko gecko to document ontogenetic changes in cranial anatomy, especially near maturity. Comparison of this species with available descriptions of other geckos resulted in the identification of 14 cranial characteristics that are expressed more strongly with size increase. These characteristics become move evident in later stages of post-hatching development, especially near maturation, and are, therefore, attributed to peramorphosis (hyperossification). ACCTRAN and DELTRAN character optimizations were applied to these characters using a tree of 11 genera derived from a gekkotan molecular phylogeny. This analysis revealed that G. gecko expresses the majority of these putative peramorphic features near maturity, and that some of these features are also expressed in species closely related to G. gecko. The characters studied have the potential to be applied in future phylogenetic and taxonomic studies of this group of lizards.

  17. [Human skull development and voice disorders].

    PubMed

    Piron, A; Roch, J B

    2006-01-01

    The hominisation of the skull comes with the bipedic posture, due to a network of muscular and aponevrotic forces applied to the cranio-facial skeleton. A brief sight of the morphogenetic origine and issues of these forces help to understand more clearly the postural statement of the larynx, his functions, and his many extrinsic biomechanical bounds; then further his most frequently dysfunctions. The larynx is surrounded by several effective systems of protection: active, activo-passive, passive. The architectural features of the components of the laryngeal system allows us to consider the laryngeal function as an auto-balanced system. All the forces engaged are auto-balanced in a continuum of tension. This lead us to the concept of tensegrity system, neologism coming from tensional integrity described by Buckminster Fuller. The laryngeal employement by extrinsic system is pathological in case of chronicity. Any osteopathic treatment, which aims to restore the losses of laryngeal mobility, has to release first the peripherical structures involved in the laryngeal defense, before normalising the larynx itself Finally, the larynx recovers his functions in a tensegrity system.

  18. Pediatric foot fractures.

    PubMed

    Ribbans, William J; Natarajan, Ramanathan; Alavala, Sairam

    2005-03-01

    Fractures of the foot in children usually have a good prognosis and generally are treated nonoperatively. Displaced fractures of the talus and calcaneus and tarsometatarsal dislocations are rare in children and their outcome is generally good in the younger child. Older adolescents with these injuries need treatment similar to how an adult would be treated for the same injury in order to achieve a good result. Foot fractures in children may pose a diagnostic challenge particularly in the absence of obvious radiographic changes. Repeated clinical examination and judicious use of imaging techniques such as isotope bone scans and magnetic resonance imaging are needed to establish a diagnosis. Knowledge of the anatomy and significance of accessory bones of the foot and disorders of the growing foot skeleton are helpful in managing injuries of child's foot. In this study, we review common injuries of a child's foot and include a discussion on differential diagnosis.

  19. Growing and Growing: Promoting Functional Thinking with Geometric Growing Patterns

    ERIC Educational Resources Information Center

    Markworth, Kimberly A.

    2010-01-01

    Design research methodology is used in this study to develop an empirically-substantiated instruction theory about students' development of functional thinking in the context of geometric growing patterns. The two research questions are: (1) How does students' functional thinking develop in the context of geometric growing patterns? (2) What are…

  20. Leonardo da Vinci's "A skull sectioned": skull and dental formula revisited.

    PubMed

    Gerrits, Peter O; Veening, Jan G

    2013-05-01

    What can be learned from historical anatomical drawings and how to incorporate these drawings into anatomical teaching? The drawing "A skull sectioned" (RL 19058v) by Leonardo da Vinci (1452-1519), hides more detailed information than reported earlier. A well-chosen section cut explores sectioned paranasal sinuses and ductus nasolacrimalis. A dissected lateral wall of the maxilla is also present. Furthermore, at the level of the foramen mentale, the drawing displays compact and spongious bony components, together with a cross-section through the foramen mentale and its connection with the canalis mandibulae. Leonardo was the first to describe a correct dental formula (6424) and made efforts to place this formula above the related dental elements. However, taking into account, the morphological features of the individual elements of the maxilla, it can be suggested that Leonardo sketched a "peculiar dental element" on the position of the right maxillary premolar in the dental sketch. The fact that the author did not make any comment on that special element is remarkable. Leonardo could have had sufficient knowledge of the precise morphology of maxillary and mandibular premolars, since the author depicted these elements in the dissected skull. The fact that the author also had access to premolars in situ corroborates our suggestion that "something went wrong" in this part of the drawing. The present study shows that historical anatomical drawings are very useful for interactive learning of detailed anatomy for students in medicine and dentistry.

  1. Earliest Directly-Dated Human Skull-Cups

    PubMed Central

    Bello, Silvia M.; Parfitt, Simon A.; Stringer, Chris B.

    2011-01-01

    Background The use of human braincases as drinking cups and containers has extensive historic and ethnographic documentation, but archaeological examples are extremely rare. In the Upper Palaeolithic of western Europe, cut-marked and broken human bones are widespread in the Magdalenian (∼15 to 12,000 years BP) and skull-cup preparation is an element of this tradition. Principal Findings Here we describe the post-mortem processing of human heads at the Upper Palaeolithic site of Gough's Cave (Somerset, England) and identify a range of modifications associated with the production of skull-cups. New analyses of human remains from Gough's Cave demonstrate the skilled post-mortem manipulation of human bodies. Results of the research suggest the processing of cadavers for the consumption of body tissues (bone marrow), accompanied by meticulous shaping of cranial vaults. The distribution of cut-marks and percussion features indicates that the skulls were scrupulously 'cleaned' of any soft tissues, and subsequently modified by controlled removal of the facial region and breakage of the cranial base along a sub-horizontal plane. The vaults were also ‘retouched’, possibly to make the broken edges more regular. This manipulation suggests the shaping of skulls to produce skull-cups. Conclusions Three skull-cups have been identified amongst the human bones from Gough's Cave. New ultrafiltered radiocarbon determinations provide direct dates of about 14,700 cal BP, making these the oldest directly dated skull-cups and the only examples known from the British Isles. PMID:21359211

  2. Surgically resected skull base meningiomas demonstrate a divergent postoperative recurrence pattern compared with non-skull base meningiomas.

    PubMed

    Mansouri, Alireza; Klironomos, George; Taslimi, Shervin; Kilian, Alex; Gentili, Fred; Khan, Osaama H; Aldape, Kenneth; Zadeh, Gelareh

    2016-08-01

    OBJECTIVE The objective of this study was to identify the natural history and clinical predictors of postoperative recurrence of skull base and non-skull base meningiomas. METHODS The authors performed a retrospective hospital-based study of all patients with meningioma referred to their institution from September 1993 to January 2014. The cohort constituted both patients with a first-time presentation and those with evidence of recurrence. Kaplan-Meier curves were constructed for analysis of recurrence and differences were assessed using the log-rank test. Cox proportional hazard regression was used to identify potential predictors of recurrence. RESULTS Overall, 398 intracranial meningiomas were reviewed, including 269 (68%) non-skull base and 129 (32%) skull base meningiomas (median follow-up 30.2 months, interquartile range [IQR] 8.5-76 months). The 10-year recurrence-free survival rates for patients with gross-total resection (GTR) and subtotal resection (STR) were 90% and 43%, respectively. Skull base tumors were associated with a lower proliferation index (0.041 vs 0.062, p = 0.001), higher likelihood of WHO Grade I (85.3% vs 69.1%, p = 0.003), and younger patient age (55.2 vs 58.3 years, p = 0.01). Meningiomas in all locations demonstrated an average recurrence rate of 30% at 100 months of follow-up. Subsequently, the recurrence of skull base meningiomas plateaued whereas non-skull base lesions had an 80% recurrence rate at 230 months follow-up (p = 0.02). On univariate analysis, a prior history of recurrence (p < 0.001), initial WHO grade following resection (p < 0.001), and the inability to obtain GTR (p < 0.001) were predictors of future recurrence. On multivariate analysis a prior history of recurrence (p = 0.02) and an STR (p < 0.01) were independent predictors of a recurrence. Assessing only patients with primary presentations, STR and WHO Grades II and III were independent predictors of recurrence (p < 0.001 for both). CONCLUSIONS Patients with skull

  3. Surgically resected skull base meningiomas demonstrate a divergent postoperative recurrence pattern compared with non-skull base meningiomas.

    PubMed

    Mansouri, Alireza; Klironomos, George; Taslimi, Shervin; Kilian, Alex; Gentili, Fred; Khan, Osaama H; Aldape, Kenneth; Zadeh, Gelareh

    2016-08-01

    OBJECTIVE The objective of this study was to identify the natural history and clinical predictors of postoperative recurrence of skull base and non-skull base meningiomas. METHODS The authors performed a retrospective hospital-based study of all patients with meningioma referred to their institution from September 1993 to January 2014. The cohort constituted both patients with a first-time presentation and those with evidence of recurrence. Kaplan-Meier curves were constructed for analysis of recurrence and differences were assessed using the log-rank test. Cox proportional hazard regression was used to identify potential predictors of recurrence. RESULTS Overall, 398 intracranial meningiomas were reviewed, including 269 (68%) non-skull base and 129 (32%) skull base meningiomas (median follow-up 30.2 months, interquartile range [IQR] 8.5-76 months). The 10-year recurrence-free survival rates for patients with gross-total resection (GTR) and subtotal resection (STR) were 90% and 43%, respectively. Skull base tumors were associated with a lower proliferation index (0.041 vs 0.062, p = 0.001), higher likelihood of WHO Grade I (85.3% vs 69.1%, p = 0.003), and younger patient age (55.2 vs 58.3 years, p = 0.01). Meningiomas in all locations demonstrated an average recurrence rate of 30% at 100 months of follow-up. Subsequently, the recurrence of skull base meningiomas plateaued whereas non-skull base lesions had an 80% recurrence rate at 230 months follow-up (p = 0.02). On univariate analysis, a prior history of recurrence (p < 0.001), initial WHO grade following resection (p < 0.001), and the inability to obtain GTR (p < 0.001) were predictors of future recurrence. On multivariate analysis a prior history of recurrence (p = 0.02) and an STR (p < 0.01) were independent predictors of a recurrence. Assessing only patients with primary presentations, STR and WHO Grades II and III were independent predictors of recurrence (p < 0.001 for both). CONCLUSIONS Patients with skull

  4. Pelvic Insufficiency Fractures

    PubMed Central

    O’Connor, Timothy J.

    2014-01-01

    Pelvic insufficiency fractures may occur in the absence of trauma or as a result of low-energy trauma in osteoporotic bone. With a growing geriatric population, the incidence of pelvic insufficiency fracture has increased over the last 3 decades and will continue to do so. These fractures can cause considerable pain, loss of independence, and economic burden to both the patient and the health care system. While many of these injuries are identified and treated based on plain radiographs, some remain difficult to diagnose. The role of advanced imaging in these cases is discussed. In addition to treating the fracture, medical comorbidities contributing to osteoporosis should be identified and corrected. Specific attention has been given to 25-OH serum vitamin D screening and repletion. Treatment generally consists of providing pain control and assisting patients with mobilization while allowing weight bearing as tolerated. In those unable to do so, invasive techniques such as sacroplasty as well as internal fixation may be beneficial. The role of operative fixation in insufficiency fractures is also discussed. PMID:26246940

  5. [Intraoperative navigation, with focus on the skull base].

    PubMed

    Wirtz, C R

    2016-09-01

    Intraoperative navigation systems are widely used in ENT, oral and maxillofacial, and neurosurgery. The benefits of such systems have been demonstrated in various applications, including intracranial and skull base surgery. Intraoperative shift, "brain shift" and changes in anatomy caused by the surgical procedure itself impair the accuracy of navigation and represent factors limiting its application, particularly in glioma and metastatic brain surgery. For this reason, intraoperative imaging was incorporated into neurosurgery. A specific application of navigation is thus skull base surgery, where shifts are often negligible due to the bony structures in which pathologies are embedded. Development of new systems with seamless integration into the operative workflow propagated routine use of navigation in neuro- and ENT surgery. Navigation proved especially helpful in interdisciplinary surgery with pathologies located in anatomic regions where competences of different surgical disciplines overlap, as in the skull base. While this increased radicality in tumour resection, there was a high risk of morbidity. The integration of electrophysiological function monitoring served to preserve function and reduce morbidity, and has led to less invasive and radical strategies in skull base surgery. New radiosurgical methods to adjuvantly treat possible tumour remnants have also supported this development. Systems allowing resection borders to be marked in the navigational coordinates would enable direct linking of these data to radiotherapy planning and better interpretation of follow-up imaging. Navigation is thus a valuable tool supporting interdisciplinary cooperation in skull base surgery for the benefit of patients. PMID:27566369

  6. The need for skull radiography in patients presenting for CT

    SciTech Connect

    Tress, B.M.

    1983-01-01

    One thousand patients had both CT of the head and a conventional skull series of radiographs. Radiographic findings were abnormal in 250 patients (25%), but only 64 patients (6.4%) had diagnostically significant abnormalities at radiography that were not detected by CT. If the 163 patients who presented after acute trauma were excluded from the series, only 39 (4.7%) of the remaining patients had radiographically significant abnormal findings that were not seen at CT, and only two (0.2%) of these abnormalities could not be diagnosed by a lateral skull radiograph alone. In only five patients (0.5%) was the management actively changed because an abnormaltiy that was detected at skull radiography was not detected at CT. Thus, in nontrauma patients who have stroke, epilepsy, dementia, or non-specific symptoms without focal signs, or have recently undergone craniotomy, and who have been referred for CT, skull radiographs are not justified. In the patient with a history and findings that are strongly suggestive of a pathological disorder anywhere other than in the sella turcica, cerebello-pontine angle, and paranasal sinuses, only the lateral skull radiograph should be obtained after CT, and only if CT is equivocal.

  7. Robotic Anterior and Midline Skull Base Surgery: Preclinical Investigations

    SciTech Connect

    O'Malley, Bert W. Weinstein, Gregory S.

    2007-10-01

    Purpose: To develop a minimally invasive surgical technique to access the midline and anterior skull base using the optical and technical advantages of robotic surgical instrumentation. Methods and Materials: Ten experimental procedures focusing on approaches to the nasopharynx, clivus, sphenoid, pituitary sella, and suprasellar regions were performed on one cadaver and one live mongrel dog. Both the cadaver and canine procedures were performed in an approved training facility using the da Vinci Surgical Robot. For the canine experiments, a transoral robotic surgery (TORS) approach was used, and for the cadaver a newly developed combined cervical-transoral robotic surgery (C-TORS) approach was investigated and compared with standard TORS. The ability to access and dissect tissues within the various areas of the midline and anterior skull base were evaluated, and techniques to enhance visualization and instrumentation were developed. Results: Standard TORS approaches did not provide adequate access to the midline and anterior skull base; however, the newly developed C-TORS approach was successful in providing the surgical access to these regions of the skull base. Conclusion: Robotic surgery is an exciting minimally invasive approach to the skull base that warrants continued preclinical investigation and development.

  8. [Intraoperative navigation, with focus on the skull base].

    PubMed

    Wirtz, C R

    2016-09-01

    Intraoperative navigation systems are widely used in ENT, oral and maxillofacial, and neurosurgery. The benefits of such systems have been demonstrated in various applications, including intracranial and skull base surgery. Intraoperative shift, "brain shift" and changes in anatomy caused by the surgical procedure itself impair the accuracy of navigation and represent factors limiting its application, particularly in glioma and metastatic brain surgery. For this reason, intraoperative imaging was incorporated into neurosurgery. A specific application of navigation is thus skull base surgery, where shifts are often negligible due to the bony structures in which pathologies are embedded. Development of new systems with seamless integration into the operative workflow propagated routine use of navigation in neuro- and ENT surgery. Navigation proved especially helpful in interdisciplinary surgery with pathologies located in anatomic regions where competences of different surgical disciplines overlap, as in the skull base. While this increased radicality in tumour resection, there was a high risk of morbidity. The integration of electrophysiological function monitoring served to preserve function and reduce morbidity, and has led to less invasive and radical strategies in skull base surgery. New radiosurgical methods to adjuvantly treat possible tumour remnants have also supported this development. Systems allowing resection borders to be marked in the navigational coordinates would enable direct linking of these data to radiotherapy planning and better interpretation of follow-up imaging. Navigation is thus a valuable tool supporting interdisciplinary cooperation in skull base surgery for the benefit of patients.

  9. Mechanical properties of the brain-skull interface.

    PubMed

    Mazumder, Mohammad Mynuddin Gani; Miller, Karol; Bunt, Stuart; Mostayed, Ahmed; Joldes, Grand; Day, Robert; Hart, Robin; Wittek, Adam

    2013-01-01

    Knowledge of the mechanical properties of the brain-skull interface is important for surgery simulation and injury biomechanics. These properties are known only to a limited extent. In this study we conducted in situ indentation of the sheep brain, and proposed to derive the macroscopic mechanical properties of the brain-skull interface from the results of these experiments. To the best of our knowledge, this is the first ever analysis of this kind. When conducting in situ indentation of the brain, the reaction force on the indentor was measured. After the indentation, a cylindrical sample of the brain tissue was extracted and subjected to uniaxial compression test. A model of the brain indentation experiment was built in the Finite Element (FE) solver ABAQUS™. In the model, the mechanical properties of the brain tissue were assigned as obtained from the uniaxial compression test and the brain-skull interface was modeled as linear springs. The interface stiffness (defined as sum of stiffnesses of the springs divided by the interface area) was varied to obtain good agreement between the calculated and experimentally measured indentor force-displacement relationship. Such agreement was found to occur for the brain-skull interface stiffness of 11.45 Nmm⁻¹/mm². This allowed identification of the overall mechanical properties of the brain-skull interface. PMID:23951996

  10. Prevention and management of positional skull deformities in infants.

    PubMed

    Laughlin, James; Luerssen, Thomas G; Dias, Mark S

    2011-12-01

    Positional skull deformities may be present at birth or may develop during the first few months of life. Since the early 1990s, US pediatricians have seen an increase in the number of children with cranial asymmetry, particularly unilateral flattening of the occiput, likely attributable to parents following the American Academy of Pediatrics "Back to Sleep" positioning recommendations aimed at decreasing the risk of sudden infant death syndrome. Positional skull deformities are generally benign, reversible head-shape anomalies that do not require surgical intervention, as opposed to craniosynostosis, which can result in neurologic damage and progressive craniofacial distortion. Although associated with some risk of positional skull deformity, healthy young infants should be placed down for sleep on their backs. The practice of putting infants to sleep on their backs has been associated with a drastic decrease in the incidence of sudden infant death syndrome. Pediatricians need to be able to properly differentiate infants with benign skull deformities from those with craniosynostosis, educate parents on methods of proactively decreasing the likelihood of the development of occipital flattening, initiate appropriate management, and make referrals when necessary. This report provides guidance for the prevention, diagnosis, and management of positional skull deformity in an otherwise normal infant without evidence of associated anomalies, syndromes, or spinal disease. PMID:22123884

  11. Geographical variation of the skull of the lesser mouse deer.

    PubMed

    Endo, Hideki; Fukuta, Katsuhiro; Kimura, Junpei; Sasaki, Motoki; Stafford, Brian J

    2004-10-01

    We examined the geographical variation of the skull size and shape of the lesser mouse deer (Tragulus javanicus) from Laos, Thailand, Peninsular Malaysia, Sumatra, Java, Borneo, Langkawi and some Islands of Tenasserim in Myanmar. Although the influence of the climatic condition on skull size was not confirmed in the mainland populations, the skull became rostro-caudally longer in the populations of Tenasserim and Sumatra because of island isolation effect. The skull size was classified into the following three clusters of localities from the matrix of Q-mode correlation coefficients: 1) Langkawi and Tenasserim, 2) Laos and Thailand, 3) Sumatra and Borneo. The skulls in the population of Java belong to the cluster of Langkawi and Tenasserim in male, however were morphologically similar to those in the cluster of Borneo and Sumatra. The canonical discriminant analysis pointed out that the Laos and Tenasserim populations were separated from the other ones and that the populations of Sumatra, Java and Borneo were intermingled each other. PMID:15528854

  12. [Radiological anatomical examinations in skulls from anthropological collections (author's transl)].

    PubMed

    Wicke, L

    1976-01-01

    A total of 114 skulls dating from the Neolithic Age, the Bronze Age and the Iron Age, of Incas and Red Indians, of Asians from North and South China, as well as Negro skulls found in Turkey were radiologically analysed and compared with control skulls of recent origin. The 3 standard X-ray views were taken (postero-anterior, axial and lateral) and appropriate linear and angle measurements were carried out. The resultant 4120 values were compared by variance analysis and the differences between the groups are presented. The differences in linear values may be attributable merely to racial variation; the constancy of the obtained angle measurements is striking. The results were also compared by means of linear regression with measured volume values of the brain skull; it was thereby possible to develop a new formula by means of which the volume of the brain skull can be calculated from the parameter BPH (introduced by the author) and from the distance B with the help of a constant factor. The importance of Radiology in Anthropology is pointed out.

  13. Predicting zygoma fractures from baseball impact.

    PubMed

    Cormier, Joseph M; Stitzel, Joel D; Hurst, William J; Porta, David J; Jones, Jeryl; Duma, Stefan M

    2006-01-01

    The purpose of this study is to develop injury risk functions that predict zygoma fracture based on baseball type and impact velocity. Zygoma fracture strength data from published experiments were mapped with the force exerted by a baseball on the orbit as a function of ball velocity. Using a normal distribution, zygoma fracture risk functions were developed. Experimental evaluation of these risk functions was performed using six human cadaver tests and two baseballs of different stiffness values. High speed video measured the baseball impact velocity. Post test analysis of the cadaver skulls was performed using CT imaging including three-dimensional reconstruction as well as autopsy. The developed injury risk functions accurately identify the risk of zygoma fracture as a result of baseball impact. The experimental results validated the zygoma risk functions at the lower and upper levels. The injuries observed in the post test analysis included fractures of the zygomatic arch, frontal process and the maxilla, zygoma suture, with combinations of these creating comminuted, tripod fractures of the zygoma. Tests with a softer baseball did result in injury but these had fewer resulting zygoma bone fragments and occurred at velocities 50% higher than the major league ball.

  14. Predicting zygoma fractures from baseball impact.

    PubMed

    Cormier, Joseph M; Stitzel, Joel D; Hurst, William J; Porta, David J; Jones, Jeryl; Duma, Stefan M

    2006-01-01

    The purpose of this study is to develop injury risk functions that predict zygoma fracture based on baseball type and impact velocity. Zygoma fracture strength data from published experiments were mapped with the force exerted by a baseball on the orbit as a function of ball velocity. Using a normal distribution, zygoma fracture risk functions were developed. Experimental evaluation of these risk functions was performed using six human cadaver tests and two baseballs of different stiffness values. High speed video measured the baseball impact velocity. Post test analysis of the cadaver skulls was performed using CT imaging including three-dimensional reconstruction as well as autopsy. The developed injury risk functions accurately identify the risk of zygoma fracture as a result of baseball impact. The experimental results validated the zygoma risk functions at the lower and upper levels. The injuries observed in the post test analysis included fractures of the zygomatic arch, frontal process and the maxilla, zygoma suture, with combinations of these creating comminuted, tripod fractures of the zygoma. Tests with a softer baseball did result in injury but these had fewer resulting zygoma bone fragments and occurred at velocities 50% higher than the major league ball. PMID:16817599

  15. Properties and architecture of the sperm whale skull amphitheatre.

    PubMed

    Alam, Parvez; Amini, Shahrouz; Tadayon, Maryam; Miserez, Ali; Chinsamy, Anusuya

    2016-02-01

    The sperm whale skull amphitheatre cradles an enormous two-tonne spermaceti organ. The amphitheatre separates this organ from the cranium and the cervical vertebrae that lie in close proximity to the base of the skull. Here, we elucidate that this skull amphitheatre is an elastic, flexible, triple-layered structure with mechanical properties that are conjointly guided by bone histology and the characteristics of pore space. We contend that the amphitheatre will flex elastically to equilibrate forces transmitted via the spermaceti organ that arise through diving. We find that collisions from sperm whale aggression do not cause the amphitheatre to bend, but rather localise stress to the base of the amphitheatre on its anterior face. We consider, therefore, that the uniquely thin and extended construction of the amphitheatre, has relevance as an energy absorptive structure in diving.

  16. Biting disrupts integration to spur skull evolution in eels.

    PubMed

    Collar, David C; Wainwright, Peter C; Alfaro, Michael E; Revell, Liam J; Mehta, Rita S

    2014-01-01

    The demand that anatomical structures work together to perform biological functions is thought to impose strong limits on morphological evolution. Breakthroughs in diversification can occur, however, when functional integration among structures is relaxed. Although such transitions are expected to generate variation in morphological diversification across the tree of life, empirical tests of this hypothesis are rare. Here we show that transitions between suction-based and biting modes of prey capture, which require different degrees of coordination among skull components, are associated with shifts in the pattern of skull diversification in eels (Anguilliformes). Biting eels have experienced greater independence of the jaws, hyoid and operculum during evolution and exhibit more varied morphologies than closely related suction feeders, and this pattern reflects the weakened functional integration among skull components required for biting. Our results suggest that behavioural transitions can change the evolutionary potential of the vertebrate skeleton by altering functional relationships among structures.

  17. Properties and architecture of the sperm whale skull amphitheatre.

    PubMed

    Alam, Parvez; Amini, Shahrouz; Tadayon, Maryam; Miserez, Ali; Chinsamy, Anusuya

    2016-02-01

    The sperm whale skull amphitheatre cradles an enormous two-tonne spermaceti organ. The amphitheatre separates this organ from the cranium and the cervical vertebrae that lie in close proximity to the base of the skull. Here, we elucidate that this skull amphitheatre is an elastic, flexible, triple-layered structure with mechanical properties that are conjointly guided by bone histology and the characteristics of pore space. We contend that the amphitheatre will flex elastically to equilibrate forces transmitted via the spermaceti organ that arise through diving. We find that collisions from sperm whale aggression do not cause the amphitheatre to bend, but rather localise stress to the base of the amphitheatre on its anterior face. We consider, therefore, that the uniquely thin and extended construction of the amphitheatre, has relevance as an energy absorptive structure in diving. PMID:26781232

  18. Fatigue Fractures

    PubMed Central

    Morris, James M.

    1968-01-01

    Fatigue (or stress) fracture of bone in military recruits has been recognized for many years. Most often it is a metatarsal bone that is involved but the tarsal bones, calcaneus, tibia, fibula, femur, and pelvis are occasionally affected. Reports of such fractures in the ribs, ulna and vertebral bodies may be found in the literature. In recent years, there has been increasing awareness of the occurrence of fatigue fractures in the civilian population. Weekend sportsmen, athletes in an early phase of training, and persons engaged in unaccustomed, repetitive, vigorous activity are potential victims of such a fracture. The signs and symptoms, roentgenographic findings, treatment and etiology of fatigue fractures are dealt with in this presentation. ImagesFigure 1.Figure 2.Figure 3.Figure 4.Figure 5.Figure 6. PMID:5652745

  19. Skull Defects in Finite Element Head Models for Source Reconstruction from Magnetoencephalography Signals.

    PubMed

    Lau, Stephan; Güllmar, Daniel; Flemming, Lars; Grayden, David B; Cook, Mark J; Wolters, Carsten H; Haueisen, Jens

    2016-01-01

    Magnetoencephalography (MEG) signals are influenced by skull defects. However, there is a lack of evidence of this influence during source reconstruction. Our objectives are to characterize errors in source reconstruction from MEG signals due to ignoring skull defects and to assess the ability of an exact finite element head model to eliminate such errors. A detailed finite element model of the head of a rabbit used in a physical experiment was constructed from magnetic resonance and co-registered computer tomography imaging that differentiated nine tissue types. Sources of the MEG measurements above intact skull and above skull defects respectively were reconstructed using a finite element model with the intact skull and one incorporating the skull defects. The forward simulation of the MEG signals reproduced the experimentally observed characteristic magnitude and topography changes due to skull defects. Sources reconstructed from measured MEG signals above intact skull matched the known physical locations and orientations. Ignoring skull defects in the head model during reconstruction displaced sources under a skull defect away from that defect. Sources next to a defect were reoriented. When skull defects, with their physical conductivity, were incorporated in the head model, the location and orientation errors were mostly eliminated. The conductivity of the skull defect material non-uniformly modulated the influence on MEG signals. We propose concrete guidelines for taking into account conducting skull defects during MEG coil placement and modeling. Exact finite element head models can improve localization of brain function, specifically after surgery. PMID:27092044

  20. Skull Defects in Finite Element Head Models for Source Reconstruction from Magnetoencephalography Signals

    PubMed Central

    Lau, Stephan; Güllmar, Daniel; Flemming, Lars; Grayden, David B.; Cook, Mark J.; Wolters, Carsten H.; Haueisen, Jens

    2016-01-01

    Magnetoencephalography (MEG) signals are influenced by skull defects. However, there is a lack of evidence of this influence during source reconstruction. Our objectives are to characterize errors in source reconstruction from MEG signals due to ignoring skull defects and to assess the ability of an exact finite element head model to eliminate such errors. A detailed finite element model of the head of a rabbit used in a physical experiment was constructed from magnetic resonance and co-registered computer tomography imaging that differentiated nine tissue types. Sources of the MEG measurements above intact skull and above skull defects respectively were reconstructed using a finite element model with the intact skull and one incorporating the skull defects. The forward simulation of the MEG signals reproduced the experimentally observed characteristic magnitude and topography changes due to skull defects. Sources reconstructed from measured MEG signals above intact skull matched the known physical locations and orientations. Ignoring skull defects in the head model during reconstruction displaced sources under a skull defect away from that defect. Sources next to a defect were reoriented. When skull defects, with their physical conductivity, were incorporated in the head model, the location and orientation errors were mostly eliminated. The conductivity of the skull defect material non-uniformly modulated the influence on MEG signals. We propose concrete guidelines for taking into account conducting skull defects during MEG coil placement and modeling. Exact finite element head models can improve localization of brain function, specifically after surgery. PMID:27092044

  1. Effect of different labor forces on fetal skull molding.

    PubMed

    Pu, Fang; Xu, Liqiang; Li, Deyu; Li, Shuyu; Sun, Lianwen; Wang, Ling; Fan, Yubo

    2011-06-01

    Fetal head molding is important for adapting the fetal head to the birth canal during vaginal delivery; however, excessive deformation of fetal head may lead to severe complications. Although labor force is one of the major factors which cause deformation of the fetal head, its effect on fetal head molding has not been quantitatively investigated yet. We examined this effect by using a finite element modeling approach. Firstly, a geometric model was created by scanning a polyethylene replica of fetal skull model with a white light three-dimensional scanner. Secondly, a nonlinear finite element model was proposed based on the geometric model. Next, the simulation results of the proposed model were verified against the experimental data reported in other literatures and they showed good agreement with the experimental observations. After this validation, the proposed model was used to simulate the fetal skull deformations under different labor forces. Simulation results illustrated that the fetal skull diameters and modified molding index (MMI) increased when the labor force was increased. Parietal bone around bregma and frontal bone around coronal suture undertook more stress, and parietal and frontal bones around coronal suture undertook more spatial and rotational displacement under larger labor force. The suboccipito-bregmatic diameter (SOBD) was more sensitive to the changes of labor force than other fetal skull diameters. The simulation results revealed the quantitative relationship between the labor force and fetal skull molding during delivery. In the future, if the degree of fetal skull molding is directly related to that of the head injury, the relationship investigated in this study may be used to predict the head injury by measuring the labor force during delivery.

  2. Surgical pathology of the skull base: a 7-year experience.

    PubMed

    Gandour-Edwards, R; Donald, P J; Boggan, J E

    1998-01-01

    A significant diversity of tissue types interface at the base of the skull and contribute to the diagnostic challenges of skull base surgical pathology. Advances in surgical technique now permit biopsy and resection of lesions previously termed "inoperable." Retrospective review was made of all pathology specimens from skull base surgeries performed at the University of California Davis Medical Center from 1990 to 1996. Surgical biopsies and resections were performed on 186 patients who had 33 distinctive diagnoses. Any preoperative biopsy or tissue from referring institutions was reviewed prior to skull base surgery. One hundred eighteen patients had benign lesions, the most frequent of which were pituitary adenoma (55) and acoustic neuroma (27). Other benign lesions included angiofibroma, meningioma, fibrous dysplasia, and paraganglioma. Sixty-eight patients had malignant tumors, 32 of which were squamous cell earcinoma. Other malignancies included salivary carcinomas, basal cell carcinoma, neuroblastoma, melanoma, and several sarcomas. Unexpected findings were two metastatic carcinomas and five inflammatory lesions. Nearly 1500 intraoperative consultations were performed to establish resection margins and less commonly to confirm the diagnosis. The discrepancy rate between the intraoperative and final diagnosis was 1.8%. Immunohistochemistry and/or electron microscopy was utilized in 44% of the specimens to confirm the diagnosis. Surgical pathology is an essential ingredient to a successful skull base surgery program. Pathologists are involved in both pre- and intraoperative decisions. The diversity of lesions that arise from the skull base often has overlapping histologies that require careful attention to morphology and the use of ancillary studies for accurate diagnosis. The need for frequent intraoperative interpretations contributes to the significant challenge for the surgical pathologist.

  3. Temporal bone fracture following blunt trauma caused by a flying fish.

    PubMed

    Goldenberg, D; Karam, M; Danino, J; Flax-Goldenberg, R; Joachims, H Z

    1998-10-01

    Blunt trauma to the temporal region can cause fracture of the skull base, loss of hearing, vestibular symptoms and otorrhoea. The most common causes of blunt trauma to the ear and surrounding area are motor vehicle accidents, violent encounters, and sports-related accidents. We present an obscure case of a man who was struck in the ear by a flying fish while wading in the sea with resulting temporal bone fracture, sudden deafness, vertigo, cerebrospinal fluid otorrhoea, and pneumocephalus.

  4. Temporal bone fracture following blunt trauma caused by a flying fish.

    PubMed

    Goldenberg, D; Karam, M; Danino, J; Flax-Goldenberg, R; Joachims, H Z

    1998-10-01

    Blunt trauma to the temporal region can cause fracture of the skull base, loss of hearing, vestibular symptoms and otorrhoea. The most common causes of blunt trauma to the ear and surrounding area are motor vehicle accidents, violent encounters, and sports-related accidents. We present an obscure case of a man who was struck in the ear by a flying fish while wading in the sea with resulting temporal bone fracture, sudden deafness, vertigo, cerebrospinal fluid otorrhoea, and pneumocephalus. PMID:10211221

  5. Nonpenetrating Clips Successfully Replacing Sutures in Base of Skull Surgery

    PubMed Central

    Kirsch, Wolff M.; Zhu, Yong Hua; Hardesty, Robert A.; Petti, George; Furnas, David

    1993-01-01

    Reconstructive challenges engendered by skull base surgery are critical determinants of outcome. A novel nonpenetrating, arcuate-legged clip has proven to be both technically and biologically effective for management of these difficult closures. Clips have facilitated reconstructions associated with the surgical management of eight skull base cases: leiomyosarcoma of the orbit, middle fossa, ptyergopalatine fossa, two meningiomas (petrotentorial, cavernous sinus), vagus nerve paraganglioma, complex traumatic orbital dural tear, and one basilar and two vertebral artery aneurysms. ImagesFigure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10Figure 11Figure 12Figure 14Figure 16Figure 17Figure 18 PMID:17170909

  6. Proton therapy for tumors of the base of the skull.

    PubMed

    Noel, Georges; Gondi, Vinai

    2016-08-01

    Relative to conventional photon irradiation, proton therapy has distinct advantages in its ability to more precisely target tumor while shielding adjacent normal tissues. In the setting of skull base tumors, proton therapy plays a critical role in the dose-escalation required for optimal tumor control of chordomas, chondrosarcomas, and malignancies of the paranasal sinuses and nasal cavity. For benign tumors such as craniopharyngiomas, pituitary adenomas and meningiomas, proton therapy can limit long-term adverse effects, such as secondary malignancies. This review summarizes published literature to date regarding the role of proton therapy in skull base tumors and introduces emerging proton therapy approaches such as pencil-beam scanning (PBS). PMID:27558252

  7. Comprehensive Postoperative Management After Endoscopic Skull Base Surgery.

    PubMed

    Tien, Duc A; Stokken, Janalee K; Recinos, Pablo F; Woodard, Troy D; Sindwani, Raj

    2016-02-01

    To maximize outcomes from endoscopic skull base surgery, careful early postoperative management is critically important. Standardized postoperative regimens are lacking. The type of reconstruction and presence and type of cerebrospinal fluid leak dictate management. If a leak is encountered intraoperatively, patients should avoid maneuvers that increase intracranial pressures for at least 1 month. Early postoperative care focuses on minimizing and managing nasal crusting. This article reviews the evidence in the literature on postoperative management, complications, and quality of life after surgery, and outlines our experience in the management of patients after endoscopic skull base surgery.

  8. Cavernous Hemangioma of the Skull and Meningioma: Association or Coincidence?

    PubMed Central

    Kilani, M.; Darmoul, M.; Hammedi, F.; Ben Nsir, A.; Hattab, M. N.

    2015-01-01

    Intraosseous cavernous hemangiomas of the skull are rare. Meningiomas are quite frequently encountered in a neurosurgical practice. The association between these two entities is nevertheless very uncommon. The authors present a case of a 72-year-old woman suffering from headache. The MRI showed a parietal meningioma with adjacent thick bone. The meningioma and the bone were removed. The histological examination confirmed the diagnosis of meningioma and revealed a cavernoma of the skull. The relationship between the lesions suggests more than a coincidental association. Several hypotheses are proposed to explain common causal connections. PMID:25960899

  9. [A skull of Mesopithecus with bite marks (author's transl)].

    PubMed

    Zapfe, H

    1981-01-01

    A skull of Mesopithecus pentelicus (Roth and Wagner) from the Turolian (Upper Miocene) of Pikermi (Greece) shows hole-shaped bitemarks. Considering the behavior and the character of the dentition of the groups of carnivores represented in Pikermi, it is supposed that these bitemarks have been caused by a felid of the size of a leopard. In the fauna of Pikermi only Metailurus parvulus (Hensel) can be taken into consideration. By the defects on a skull of a juvenile Australopithecine, interpreted by Brain in 1970 as bitemarks of a leopard, the above explanation gets a very essential support. PMID:6792015

  10. If the skull fits: magnetic resonance imaging and microcomputed tomography for combined analysis of brain and skull phenotypes in the mouse.

    PubMed

    Nieman, Brian J; Blank, Marissa C; Roman, Brian B; Henkelman, R Mark; Millen, Kathleen J

    2012-10-17

    The mammalian brain and skull develop concurrently in a coordinated manner, consistently producing a brain and skull that fit tightly together. It is common that abnormalities in one are associated with related abnormalities in the other. However, this is not always the case. A complete characterization of the relationship between brain and skull phenotypes is necessary to understand the mechanisms that cause them to be coordinated or divergent and to provide perspective on the potential diagnostic or prognostic significance of brain and skull phenotypes. We demonstrate the combined use of magnetic resonance imaging and microcomputed tomography for analysis of brain and skull phenotypes in the mouse. Co-registration of brain and skull images allows comparison of the relationship between phenotypes in the brain and those in the skull. We observe a close fit between the brain and skull of two genetic mouse models that both show abnormal brain and skull phenotypes. Application of these three-dimensional image analyses in a broader range of mouse mutants will provide a map of the relationships between brain and skull phenotypes generally and allow characterization of patterns of similarities and differences.

  11. If the skull fits: magnetic resonance imaging and microcomputed tomography for combined analysis of brain and skull phenotypes in the mouse

    PubMed Central

    Blank, Marissa C.; Roman, Brian B.; Henkelman, R. Mark; Millen, Kathleen J.

    2012-01-01

    The mammalian brain and skull develop concurrently in a coordinated manner, consistently producing a brain and skull that fit tightly together. It is common that abnormalities in one are associated with related abnormalities in the other. However, this is not always the case. A complete characterization of the relationship between brain and skull phenotypes is necessary to understand the mechanisms that cause them to be coordinated or divergent and to provide perspective on the potential diagnostic or prognostic significance of brain and skull phenotypes. We demonstrate the combined use of magnetic resonance imaging and microcomputed tomography for analysis of brain and skull phenotypes in the mouse. Co-registration of brain and skull images allows comparison of the relationship between phenotypes in the brain and those in the skull. We observe a close fit between the brain and skull of two genetic mouse models that both show abnormal brain and skull phenotypes. Application of these three-dimensional image analyses in a broader range of mouse mutants will provide a map of the relationships between brain and skull phenotypes generally and allow characterization of patterns of similarities and differences. PMID:22947655

  12. Gravity-Driven Hydraulic Fractures

    NASA Astrophysics Data System (ADS)

    Germanovich, L. N.; Garagash, D.; Murdoch, L. C.; Robinowitz, M.

    2014-12-01

    This study is motived by a new method for disposing of nuclear waste by injecting it as a dense slurry into a hydraulic fracture that grows downward to great enough depth to permanently isolate the waste. Disposing of nuclear waste using gravity-driven hydraulic fractures is mechanically similar to the upward growth of dikes filled with low density magma. A fundamental question in both applications is how the injected fluid controls the propagation dynamics and fracture geometry (depth and breadth) in three dimensions. Analog experiments in gelatin [e.g., Heimpel and Olson, 1994; Taisne and Tait, 2009] show that fracture breadth (the short horizontal dimension) remains nearly stationary when the process in the fracture "head" (where breadth is controlled) is dominated by solid toughness, whereas viscous fluid dissipation is dominant in the fracture tail. We model propagation of the resulting gravity-driven (buoyant or sinking), finger-like fracture of stationary breadth with slowly varying opening along the crack length. The elastic response to fluid loading in a horizontal cross-section is local and can be treated similar to the classical Perkins-Kern-Nordgren (PKN) model of hydraulic fracturing. The propagation condition for a finger-like crack is based on balancing the global energy release rate due to a unit crack extension with the rock fracture toughness. It allows us to relate the net fluid pressure at the tip to the fracture breadth and rock toughness. Unlike the PKN fracture, where breadth is known a priori, the final breadth of a finger-like fracture is a result of processes in the fracture head. Because the head is much more open than the tail, viscous pressure drop in the head can be neglected leading to a 3D analog of Weertman's hydrostatic pulse. This requires relaxing the local elasticity assumption of the PKN model in the fracture head. As a result, we resolve the breadth, and then match the viscosity-dominated tail with the 3-D, toughness

  13. Fracture Management

    MedlinePlus

    ... to hold the fracture in the correct position. • Fiberglass casting is lighter and stronger and the exterior ... with your physician if this occurs. • When a fiberglass cast is used in conjunction with a GORE- ...

  14. Human Temporal Bone Removal: The Skull Base Block Method.

    PubMed

    Dinh, Christine; Szczupak, Mikhaylo; Moon, Seo; Angeli, Simon; Eshraghi, Adrien; Telischi, Fred F

    2015-08-01

    Objectives To describe a technique for harvesting larger temporal bone specimens from human cadavers for the training of otolaryngology residents and fellows on the various approaches to the lateral and posterolateral skull base. Design Human cadaveric anatomical study. The calvarium was excised 6 cm above the superior aspect of the ear canal. The brain and cerebellum were carefully removed, and the cranial nerves were cut sharply. Two bony cuts were performed, one in the midsagittal plane and the other in the coronal plane at the level of the optic foramen. Setting Medical school anatomy laboratory. Participants Human cadavers. Main Outcome Measures Anatomical contents of specimens and technical effort required. Results Larger temporal bone specimens containing portions of the parietal, occipital, and sphenoidal bones were consistently obtained using this technique of two bone cuts. All specimens were inspected and contained pertinent surface and skull base landmarks. Conclusions The skull base block method allows for larger temporal bone specimens using a two bone cut technique that is efficient and reproducible. These specimens have the necessary anatomical bony landmarks for studying the complexity, utility, and limitations of lateral and posterolateral approaches to the skull base, important for the education of otolaryngology residents and fellows.

  15. Skull counting in late stages after internal contamination by actinides.

    PubMed

    Tani, Kotaro; Shutt, Arron; Kurihara, Osamu; Kosako, Toshiso

    2015-02-01

    Monitoring preparation for internal contamination with actinides (e.g. Pu and Am) is required to assess internal doses at nuclear fuel cycle-related facilities. In this paper, the authors focus on skull counting in case of single-incident inhalation of (241)Am and propose an effective procedure for skull counting with an existing system, taking into account the biokinetic behaviour of (241)Am in the human body. The predicted response of the system to skull counting under a certain counting geometry was found to be only ∼1.0 × 10(-5) cps Bq(-1) 1y after intake. However, this disadvantage could be remedied by repeated measurements of the skull during the late stage of the intake due to the predicted response reaching a plateau at about the 1000th day after exposure and exceeding that in the lung counting. Further studies are needed for the development of a new detection system with higher sensitivity to perform reliable internal dose estimations based on direct measurements.

  16. Reliability of Craniofacial Superimposition Using Three-Dimension Skull Model.

    PubMed

    Gaudio, Daniel; Olivieri, Lara; De Angelis, Danilo; Poppa, Pasquale; Galassi, Andrea; Cattaneo, Cristina

    2016-01-01

    Craniofacial superimposition is a technique potentially useful for the identification of unidentified human remains if a photo of the missing person is available. We have tested the reliability of the 2D-3D computer-aided nonautomatic superimposition techniques. Three-dimension laser scans of five skulls and ten photographs were overlaid with an imaging software. The resulting superimpositions were evaluated using three methods: craniofacial landmarks, morphological features, and a combination of the two. A 3D model of each skull without its mandible was tested for superimposition; we also evaluated whether separating skulls by sex would increase correct identifications. Results show that the landmark method employing the entire skull is the more reliable one (5/5 correct identifications, 40% false positives [FP]), regardless of sex. However, the persistence of a high percentage of FP in all the methods evaluated indicates that these methods are unreliable for positive identification although the landmark-only method could be useful for exclusion. PMID:26335587

  17. Evolution of Skull and Mandible Shape in Cats (Carnivora: Felidae)

    PubMed Central

    Christiansen, Per

    2008-01-01

    The felid family consists of two major subgroups, the sabretoothed and the feline cats, to which all extant species belong, and are the most anatomically derived of all carnivores for predation on large prey with a precision killing bite. There has been much controversy and uncertainty about why the skulls and mandibles of sabretoothed and feline cats evolved to become so anatomically divergent, but previous models have focused on single characters and no unifying hypothesis of evolutionary shape changes has been formulated. Here I show that the shape of the skull and mandible in derived sabrecats occupy entirely different positions within overall morphospace from feline cats, and that the evolution of skull and mandible shape has followed very different paths in the two subgroups. When normalised for body-size differences, evolution of bite forces differ markedly in the two groups, and are much lower in derived sabrecats, and they show a significant relationship with size and cranial shape, whereas no such relationship is present in feline cats. Evolution of skull and mandible shape in modern cats has been governed by the need for uniform powerful biting irrespective of body size, whereas in sabrecats, shape evolution was governed by selective pressures for efficient predation with hypertrophied upper canines at high gape angles, and bite forces were secondary and became progressively weaker during sabrecat evolution. The current study emphasises combinations of new techniques for morphological shape analysis and biomechanical studies to formulate evolutionary hypotheses for difficult groups. PMID:18665225

  18. Human Temporal Bone Removal: The Skull Base Block Method.

    PubMed

    Dinh, Christine; Szczupak, Mikhaylo; Moon, Seo; Angeli, Simon; Eshraghi, Adrien; Telischi, Fred F

    2015-08-01

    Objectives To describe a technique for harvesting larger temporal bone specimens from human cadavers for the training of otolaryngology residents and fellows on the various approaches to the lateral and posterolateral skull base. Design Human cadaveric anatomical study. The calvarium was excised 6 cm above the superior aspect of the ear canal. The brain and cerebellum were carefully removed, and the cranial nerves were cut sharply. Two bony cuts were performed, one in the midsagittal plane and the other in the coronal plane at the level of the optic foramen. Setting Medical school anatomy laboratory. Participants Human cadavers. Main Outcome Measures Anatomical contents of specimens and technical effort required. Results Larger temporal bone specimens containing portions of the parietal, occipital, and sphenoidal bones were consistently obtained using this technique of two bone cuts. All specimens were inspected and contained pertinent surface and skull base landmarks. Conclusions The skull base block method allows for larger temporal bone specimens using a two bone cut technique that is efficient and reproducible. These specimens have the necessary anatomical bony landmarks for studying the complexity, utility, and limitations of lateral and posterolateral approaches to the skull base, important for the education of otolaryngology residents and fellows. PMID:26225316

  19. The Costs of Skull Base Surgery in the Pediatric Population

    PubMed Central

    Stapleton, A. L.; Tyler-Kabara, E. C.; Gardner, P. A.; Snyderman, C. H.

    2014-01-01

    Objectives To determine the costs of endoscopic endonasal surgery (EES) for pediatric skull base lesions. Methods Retrospective chart review of pediatric patients (ages 1 month to 19 years) treated for skull base lesions with EES from 1999 to 2013. Demographic and operative data were recorded. The cost of care for the surgical day, intensive care unit (ICU), floor, and total overall cost of inpatient stay were acquired from the finance department. Results A total of 160 pediatric patients undergoing EES for skull base lesions were identified. Of these, 55 patients had complete financial data available. The average total inpatient and surgical costs of care were $34, 056 per patient. Angiofibromas were the most costly: $59,051 per patient. Fibro-osseous lesions had the lowest costs: $10,931 per patient. The average ICU stay was 1.8 days at $4,577 per ICU day. The average acute care stay was 3.4 days at $1,961 per day. Overall length of stay was 4.5 days. Three cerebrospinal fluid leaks (4%) and two cases of meningitis (3%) occurred. One tracheostomy was required (1.5%). Conclusions EES is a cost-effective model for removal of skull base lesions in the pediatric population. Costs of care vary according to pathology, staged surgeries, length of ICU stay, and need for second operations. PMID:25685648

  20. Skull Size and Intelligence, and King Robert Bruce's IQ

    ERIC Educational Resources Information Center

    Deary, Ian J.; Ferguson, Karen J.; Bastin, Mark E.; Barrow, Geoffrey W. S.; Reid, Louise M.; Seckl, Jonathan R.; Wardlaw, Joanna M.; MacLullich, Alasdair M. J.

    2007-01-01

    An estimate of someone's IQ is a potentially informative personal datum. This study examines the association between external skull measurements and IQ scores, and uses the resulting regression equation to provide an estimate of the IQ of King Robert I of Scotland (Robert Bruce, 1274-1329). Participants were 48 relatively healthy Caucasian men…

  1. Management of Anterior Skull Base Cerebrospinal Fluid Leaks.

    PubMed

    Le, Christopher; Strong, E Bradley; Luu, Quang

    2016-10-01

    Cerebrospinal fluid (CSF) leak occurs from traumatic, iatrogenic, and idiopathic etiologies. Its timely diagnosis requires clinical, radiographic, and laboratory testing. Medical and surgical management can mitigate the risk of life-threatening infection and morbidity. This article outlines the pathophysiology, diagnosis, and management or CSF leak of the anterior skull base. PMID:27648397

  2. A Quantitative Analysis of Published Skull Base Endoscopy Literature.

    PubMed

    Hardesty, Douglas A; Ponce, Francisco A; Little, Andrew S; Nakaji, Peter

    2016-02-01

    Objectives Skull base endoscopy allows for minimal access approaches to the sinonasal contents and cranial base. Advances in endoscopic technique and applications have been published rapidly in recent decades. Setting We utilized an Internet-based scholarly database (Web of Science, Thomson Reuters) to query broad-based phrases regarding skull base endoscopy literature. Participants All skull base endoscopy publications. Main Outcome Measures Standard bibliometrics outcomes. Results We identified 4,082 relevant skull base endoscopy English-language articles published between 1973 and 2014. The 50 top-cited publications (n = 51, due to articles with equal citation counts) ranged in citation count from 397 to 88. Most of the articles were clinical case series or technique descriptions. Most (96% [49/51])were published in journals specific to either neurosurgery or otolaryngology. Conclusions A relatively small number of institutions and individuals have published a large amount of the literature. Most of the publications consisted of case series and technical advances, with a lack of randomized trials. PMID:26949585

  3. Paul Broca's search for Basque skulls: The full story.

    PubMed

    Giménez-Roldán, Santiago

    2016-01-01

    Paul Broca surmised that the short and broad-brachycephalic-skulls of the earliest European settlers had become longer and narrower-dolichocephalic-in modern populations due to the blending of different races. Swedish anatomist Anders Retzius had two brachycephalic skulls said to be from contemporary Basque individuals, a claim suited to test Broca's hypothesis. Broca worked with fellow anatomist and surgeon Pedro González Velasco, the founding father of Spanish anthropology, to gather a large number of Basque skulls. In its time, this was the most fascinating collection owned by the Anthropological Society of Paris. This article explains how Broca and Velasco were able to gather such a sizeable array of specimens, which they had collected at a location known at first by the code name of "Z." Although Broca finally concluded that the origin of the Retzius skulls could not be determined, his research was to spark anthropologists' interest in the language and origins of the Basque people. PMID:27684552

  4. Chondroblastoma-like chondroma of soft tissue: report of the first case in the base of skull.

    PubMed

    Raparia, Kirtee; Lin, Jerry W; Donovan, Donald; Vrabec, Jeffrey T; Zhai, Qihui Jim; Ayala, Alberto A; Ro, Jae Y

    2013-06-01

    Chondroblastoma-like chondroma (CLC) of soft tissue is a rare benign neoplasm that usually involves the soft tissues of the hand. This report describes the first case of CLC of soft tissue arising in the base of the skull. A 33-year-old man was seen with a slow growing mass in the right parotid region of his face. The noncontrast computed tomographic scans showed an 8.5-cm mass with calcifications involving the right masticator space and extending through the bone into the middle cranial fossa. The radiologic differential diagnosis included osteosarcoma, leiomyosarcoma, chondrosarcoma, and giant cell tumor. During surgery, the large lateral skull base tumor appeared to involve the middle and infratemporal fossae and eroded the surrounding bone. Although the tumor was removed piecemeal, total excision was performed. On microscopic examination, the tumor displayed lobules of mature hyaline cartilage with numerous chondroblasts, coarse calcifications including chicken wire calcifications, and scattered osteoclasts. No atypia, mitoses, necrosis, or osteoid formation was seen. The tumor was diagnosed as chondroma with chondroblastoma features of the soft tissue. His postoperative clinical course was uneventful; however, after 7 months, he had a local recurrence identified on follow-up magnetic resonance imaging. He underwent repeat surgical excision of the tumor, which showed similar histology as the previous excision. This large skull based tumor eroding the bone, which clinically and radiologically mimicked a malignant process, was an unusual presentation of a benign cartilaginous neoplasm. Pathologists should be aware that CLC may occur in the base of the skull and this lesion should be differentiated from the other benign or malignant tumors arising in this area. These lesions have a potential for local recurrence; hence, a close follow-up is recommended.

  5. Chondroblastoma-like chondroma of soft tissue: report of the first case in the base of skull.

    PubMed

    Raparia, Kirtee; Lin, Jerry W; Donovan, Donald; Vrabec, Jeffrey T; Zhai, Qihui Jim; Ayala, Alberto A; Ro, Jae Y

    2013-06-01

    Chondroblastoma-like chondroma (CLC) of soft tissue is a rare benign neoplasm that usually involves the soft tissues of the hand. This report describes the first case of CLC of soft tissue arising in the base of the skull. A 33-year-old man was seen with a slow growing mass in the right parotid region of his face. The noncontrast computed tomographic scans showed an 8.5-cm mass with calcifications involving the right masticator space and extending through the bone into the middle cranial fossa. The radiologic differential diagnosis included osteosarcoma, leiomyosarcoma, chondrosarcoma, and giant cell tumor. During surgery, the large lateral skull base tumor appeared to involve the middle and infratemporal fossae and eroded the surrounding bone. Although the tumor was removed piecemeal, total excision was performed. On microscopic examination, the tumor displayed lobules of mature hyaline cartilage with numerous chondroblasts, coarse calcifications including chicken wire calcifications, and scattered osteoclasts. No atypia, mitoses, necrosis, or osteoid formation was seen. The tumor was diagnosed as chondroma with chondroblastoma features of the soft tissue. His postoperative clinical course was uneventful; however, after 7 months, he had a local recurrence identified on follow-up magnetic resonance imaging. He underwent repeat surgical excision of the tumor, which showed similar histology as the previous excision. This large skull based tumor eroding the bone, which clinically and radiologically mimicked a malignant process, was an unusual presentation of a benign cartilaginous neoplasm. Pathologists should be aware that CLC may occur in the base of the skull and this lesion should be differentiated from the other benign or malignant tumors arising in this area. These lesions have a potential for local recurrence; hence, a close follow-up is recommended. PMID:22743240

  6. Lisfranc fractures.

    PubMed

    Wright, Amanda; Gerhart, Ann E

    2009-01-01

    Injuries of the tarsometatarsal, or Lisfranc, joint are rarely seen. Lisfranc fractures and fracture dislocations are among the most frequently misdiagnosed foot injuries in the emergency department. A misdiagnosed injury may have severe consequences including chronic pain and loss of foot biomechanics. Evaluation of a foot injury should include a high level of suspicion of a Lisfranc injury, and a thorough work-up is needed for correct diagnosis.

  7. Function-dependent shape characteristics of the human skull.

    PubMed

    Witzel, U; Preuschoft, H

    2002-06-01

    Using the FEM-program ANSYS 5.4, we have shaped a model of the human skull in which the flow of forces and the relative location and magnitudes of stresses are investigated. Forces are applied from below through the tooth row of the upper jaw. An ample volume is provided for the transmission of these bite forces upward to the roof of the braincase, where bearings counteract the forces from below. Within this volume, no other morphological features are considered than two cone-shaped orbits and a nasal channel which has a rounded, triangular cross section, extending upward between the orbits. Under loads (= bite forces) acting simultaneously in the directions and relative sizes of realistic bite- and chewing forces, there occurred stress concentrations inside the model which resemble closely the morphological characteristics of the human skull. The most remarkable pathways of stresses correspond to Toldt's and Benninghoff's nasal, zygomatic and pterygoid pillars. Aside from these stress concentrations, stress-free regions become visible at places, where the skull shows excavations: the vaulted palate with canalis incisivus, the canine fossa, superior and inferior orbital fissure, or cavities like the maxillary sinuses and cavum cranii. Behind the posterior molars and the pterygoid, the stresses disappear abruptly, and in the side wall of the nasal cavity a maxillary hiatus remains without stresses. A flow of forces comparable to, but not at the exact position of the zygomatic arch extends from the highly stressed zygomatic bone rearward and upward. In a later step of simulation, somewhat deeper, at the place of the really existing zygomatic arch, a series of small forces was applied, which correspond to the resultant force that is created by the redirection of the pull of the m. masseter into the temporal fascia. This--biologically reasonable--manipulation of the model leads to a reduction of the forces in the zygomatic bone, and to a downward shift of the zygomatic

  8. Typical external skull beveling wound unlinked with a gunshot.

    PubMed

    Delannoy, Y; Colard, T; Becart, A; Tournel, G; Gosset, D; Hedouin, V

    2013-03-10

    Lesions of the cranial vault resulting from firearms are traditionally described in forensic medical literature with many reports illustrating atypical bone lesions carried out to the skull by gunshot wounds. The authors present this report which illustrates an external beveled skull wound, associated with internal beveling damage, caused by a stabbing injury. A partially buried human skeleton was found in a forest. The examining of the skull revealed a hole resembling the exit wound caused by a bullet and two other smaller stab wounds. No typical entering bullet wound and no other bone lesions were found. During the course of the investigation, one of the perpetrators admitted to hitting the victim, using a sickle, and to hiding the body. For this purpose, he dragged the corpse with the sickle still implanted in the skull, using it as a hook. Upon retrieving the sickle, a piece of cranial vault was removed, thus creating an external beveled wound. In order to identify the mechanism which brought about this kind of lesion, experimental work was carried out on a human skull. In this particular case, the tip of the sickle penetrated into the bone, creating a lesion that would typically be produced with a stabbing instrument when applied with vertical force. When the body was dragged, using the sickle as a hook, this was a hand-produced vertical force, which was applied in the opposite direction. It caused the tearing of a piece of bone and the creation of an outer bevel. This atypical lesion should be made known to medical examiners and pathologists in order to help investigating and understanding of the circumstances of injuries.

  9. Can we abolish skull x rays for head injury?

    PubMed Central

    Reed, M; Browning, J; Wilkinson, A; Beattie, T

    2005-01-01

    Objectives: To assess the effect of a change in skull x ray policy on the rate of admission, use of computed tomography (CT), radiation dose per head injury, and detection of intracranial injuries; and to compare the characteristics of patients with normal and abnormal head CT. Design: Retrospective cohort study. Setting: UK paediatric teaching hospital emergency department. Patients: 1535 patients aged between 1 and 14 years with a head injury presenting to the emergency department between 1 August 1998 and 31 July 1999 (control period), and 1867 presenting between 1 August 2002 and 31 July 2003 (first year of new skull x ray policy). Intervention: Hospital notes and computer systems were analysed and data were collected on all patients presenting with a head injury. Results: The abolition of skull x rays in children aged over 1 year prevented about 400 normal skull x rays being undertaken in period 2. The percentage of children undergoing CT rose from 1.0% to 2.1% with no change in the positive CT pick up rate (25.6% v 25.0%). There was no significant change in admission rate (10.9% v 10.1%), and a slight decrease in the radiation dose per head injury (0.042 mSv compared to 0.045 mSv). Conclusions: Skull x rays can be abandoned in children aged 1 to 14 without a significant increase in admission rate, radiation dose per head injury, or missed intracranial injury. The mechanism and history of the injury and a reduced Glasgow coma scale are probably the most important indicators of significant head injury in children. PMID:15851418

  10. A giant pliosaurid skull from the late Jurassic of England.

    PubMed

    Benson, Roger B J; Evans, Mark; Smith, Adam S; Sassoon, Judyth; Moore-Faye, Scott; Ketchum, Hilary F; Forrest, Richard

    2013-01-01

    Pliosaurids were a long-lived and cosmopolitan group of marine predators that spanned 110 million years and occupied the upper tiers of marine ecosystems from the Middle Jurassic until the early Late Cretaceous. A well-preserved giant pliosaurid skull from the Late Jurassic Kimmeridge Clay Formation of Dorset, United Kingdom, represents a new species, Pliosaurus kevani. This specimen is described in detail, and the taxonomy and systematics of Late Jurassic pliosaurids is revised. We name two additional new species, Pliosaurus carpenteri and Pliosaurus westburyensis, based on previously described relatively complete, well-preserved remains. Most or all Late Jurassic pliosaurids represent a globally distributed monophyletic group (the genus Pliosaurus, excluding 'Pliosaurus' andrewsi). Despite its high species diversity, and geographically widespread, temporally extensive occurrence, Pliosaurus shows relatively less morphological and ecological variation than is seen in earlier, multi-genus pliosaurid assemblages such as that of the Middle Jurassic Oxford Clay Formation. It also shows less ecological variation than the pliosaurid-like Cretaceous clade Polycotylidae. Species of Pliosaurus had robust skulls, large body sizes (with skull lengths of 1.7-2.1 metres), and trihedral or subtrihedral teeth suggesting macropredaceous habits. Our data support a trend of decreasing length of the mandibular symphysis through Late Jurassic time, as previously suggested. This may be correlated with increasing adaptation to feeding on large prey. Maximum body size of pliosaurids increased from their first appearance in the Early Jurassic until the Early Cretaceous (skull lengths up to 2360 mm). However, some reduction occurred before their final extinction in the early Late Cretaceous (skull lengths up to 1750 mm).

  11. A Giant Pliosaurid Skull from the Late Jurassic of England

    PubMed Central

    Benson, Roger B. J.; Evans, Mark; Smith, Adam S.; Sassoon, Judyth; Moore-Faye, Scott; Ketchum, Hilary F.; Forrest, Richard

    2013-01-01

    Pliosaurids were a long-lived and cosmopolitan group of marine predators that spanned 110 million years and occupied the upper tiers of marine ecosystems from the Middle Jurassic until the early Late Cretaceous. A well-preserved giant pliosaurid skull from the Late Jurassic Kimmeridge Clay Formation of Dorset, United Kingdom, represents a new species, Pliosaurus kevani. This specimen is described in detail, and the taxonomy and systematics of Late Jurassic pliosaurids is revised. We name two additional new species, Pliosaurus carpenteri and Pliosaurus westburyensis, based on previously described relatively complete, well-preserved remains. Most or all Late Jurassic pliosaurids represent a globally distributed monophyletic group (the genus Pliosaurus, excluding ‘Pliosaurus’ andrewsi). Despite its high species diversity, and geographically widespread, temporally extensive occurrence, Pliosaurus shows relatively less morphological and ecological variation than is seen in earlier, multi-genus pliosaurid assemblages such as that of the Middle Jurassic Oxford Clay Formation. It also shows less ecological variation than the pliosaurid-like Cretaceous clade Polycotylidae. Species of Pliosaurus had robust skulls, large body sizes (with skull lengths of 1.7–2.1 metres), and trihedral or subtrihedral teeth suggesting macropredaceous habits. Our data support a trend of decreasing length of the mandibular symphysis through Late Jurassic time, as previously suggested. This may be correlated with increasing adaptation to feeding on large prey. Maximum body size of pliosaurids increased from their first appearance in the Early Jurassic until the Early Cretaceous (skull lengths up to 2360 mm). However, some reduction occurred before their final extinction in the early Late Cretaceous (skull lengths up to 1750 mm). PMID:23741520

  12. Micrometeorite Impacts in Beringian Mammoth Tusks and a Bison Skull

    SciTech Connect

    Hagstrum, Jonathon T.; Firestone, Richard B; West, Allen; Stefanka, Zsolt; Revay, Zsolt

    2010-02-03

    We have discovered what appear to be micrometeorites imbedded in seven late Pleistocene Alaskan mammoth tusks and a Siberian bison skull. The micrometeorites apparently shattered on impact leaving 2 to 5 mm hemispherical debris patterns surrounded by carbonized rings. Multiple impacts are observed on only one side of the tusks and skull consistent with the micrometeorites having come from a single direction. The impact sites are strongly magnetic indicating significant iron content. We analyzed several imbedded micrometeorite fragments from both tusks and skull with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) and X-ray fluorescence (XRF). These analyses confirm the high iron content and indicate compositions highly enriched in nickel and depleted in titanium, unlike any natural terrestrial sources. In addition, electron microprobe (EMP) analyses of a Fe-Ni sulfide grain (tusk 2) show it contains between 3 and 20 weight percent Ni. Prompt gamma-ray activation analysis (PGAA) of a particle extracted from the bison skull indicates ~;;0.4 mg of iron, in agreement with a micrometeorite ~;;1 mm in diameter. In addition, scanning electron microscope (SEM) images and XRF analyses of the skull show possible entry channels containing Fe-rich material. The majority of tusks (5/7) have a calibrated weighted mean 14C age of 32.9 +- 1.8 ka BP, which coincides with the onset of significant declines<36 ka ago in Beringian bison, horse, brown bear, and mammoth populations, as well as in mammoth genetic diversity. It appears likely that the impacts and population declines are related events, although their precise nature remains to be determined.

  13. Longitudinal and Shear Mode Ultrasound Propagation in Human Skull Bone

    NASA Astrophysics Data System (ADS)

    White, P. J.; Hynynen, K.; Clement, G. T.

    2006-05-01

    Recent studies have attempted to dispel the idea of the longitudinal mode being the only significant mode of ultrasound energy transport through the skull bone. The inclusion of shear waves in propagation models has been largely ignored because of an assumption that shear mode conversions from the skull interfaces to the surrounding media rendered the resulting acoustic field insignificant in amplitude and overly distorted. Experimental investigations with isotropic phantom materials and ex vivo human skulls demonstrated that in certain cases, a shear mode propagation scenario not only can be less distorted, but at times allowed for a substantial (as much as 36% of the longitudinal pressure amplitude) transmission of energy. The phase speed of 1.0-MHz shear mode propagation through ex vivo human skull specimens has been measured to be nearly half of that of the longitudinal mode (shear sound speed = 1500±140 m/s, longitudinal sound speed = 2820±40 m/s), demonstrating that a closer match in impedance can be achieved between the skull and surrounding soft tissues with shear mode transmission. By comparing propagation model results with measurements of transcranial ultrasound transmission obtained by a radiation force method, the attenuation coefficients for the longitudinal mode of propagation was determined to between 14 Np/m and 70 Np/m for the frequency range studied while the same for shear waves were found to be between 94 Np/m and 213 Np/m. This study was performed within the frequency range of 0.2-0.9 MHz.

  14. Superimposition-based personal identification using skull computed tomographic images: application to skull with mouth fixed open by residual soft tissue.

    PubMed

    Ishii, Masuko; Saitoh, Hisako; Yasjima, Daisuke; Yohsuk, Makino; Sakuma, Ayaka; Yayama, Kazuhiro; Iwase, Hirotaro

    2013-09-01

    We previously reported that superimposition of 3-dimensional (3D) images reconstructed from computed tomographic images of skeletonized skulls on photographs of the actual skulls afforded a match of skull contours, thereby demonstrating that superimposition of 3D-reconstructed images provides results identical to those obtained with actual skulls. The current superimposition procedure requires a skeletonized skull with mouth closed and thus is not applicable to personal identification using a skull with residual soft tissue or the mouth fixed open, such as those found in mummified or burned bodies. In this study, we scanned using computed tomography the skulls of mummified and immersed body with mandibles fixed open by residual soft tissue, created 3D-reconstructed skull images, which were digitally processed by computer software to close the mandible, and superimposed the images on antemortem facial photographs. The results demonstrated morphological consistency between the 3D-reconstructed skull images and facial photographs, indicating the applicability of the method to personal identification.

  15. Predicting and Preventing Skull Overheating in Non Invasive Brain HIFU Treatment Protocols

    SciTech Connect

    Pernot, Mathieu; Aubry, Jean-Francois; Tanter, Mickael; Fink, Mathias

    2005-03-28

    Ultrasound brain therapy is currently limited by the strong phase and amplitude aberrations induced by the heterogeneities of the skull. However the development of aberration correction techniques has made it possible to correct the beam distortion induced by the skull and to produce a sharp focus in the brain. Moreover, using the density of the skull bone that can be obtained with high-resolution CT scans, the corrections needed to produce this sharp focus can be calculated using ultrasound propagation models. We propose here a model for computing the temperature elevation in the skull during High Intensity Focused Ultrasound (HIFU) transcranial therapy. Based on CT scans, the wave propagation through the skull is computed with 3D finite differences wave propagation software. The acoustic simulation is combined with a 3D thermal diffusion code and the temperature elevation inside the skull is computed. Finally, the simulation is validated experimentally by measuring the temperature elevation in several locations of the skull.

  16. Galeazzi fracture.

    PubMed

    Atesok, Kivanc I; Jupiter, Jesse B; Weiss, Arnold-Peter C

    2011-10-01

    Galeazzi fracture is a fracture of the radial diaphysis with disruption at the distal radioulnar joint (DRUJ). Typically, the mechanism of injury is forceful axial loading and torsion of the forearm. Diagnosis is established on radiographic evaluation. Underdiagnosis is common because disruption of the ligamentous restraints of the DRUJ may be overlooked. Nonsurgical management with anatomic reduction and immobilization in a long-arm cast has been successful in children. In adults, nonsurgical treatment typically fails because of deforming forces acting on the distal radius and DRUJ. Open reduction and internal fixation is the preferred surgical option. Anatomic reduction and rigid fixation should be followed by intraoperative assessment of the DRUJ. Further intraoperative interventions are based on the reducibility and postreduction stability of the DRUJ. Misdiagnosis or inadequate management of Galeazzi fracture may result in disabling complications, such as DRUJ instability, malunion, limited forearm range of motion, chronic wrist pain, and osteoarthritis.

  17. Pediatric Thighbone (Femur) Fracture

    MedlinePlus

    ... fractures in infants under 1 year old is child abuse. Child abuse is also a leading cause of thighbone fracture ... contact sports • Being in a motor vehicle accident • Child abuse Types of Femur Fractures (Classification) Femur fractures vary ...

  18. Reconstruction of skull defects in the middle ages and renaissance.

    PubMed

    Missori, Paolo; Currà, Antonio; Paris, Harry S; Peschillo, Simone; Fattapposta, Francesco; Paolini, Sergio; Domenicucci, Maurizio

    2015-06-01

    In Egyptian, Greco-Roman, and Arabic medicine, the closure of a skull defect was not provided at the end of a therapeutic trepanation or in cases of bone removal. The literature from the Middle Ages and Renaissance disclosed some striking and forgotten practices. Gilbertus Anglicus (c. 1180 to c. 1250) cites the use of a piece of a cup made from wooden bowl (ciphum or mazer) or a gold sheet to cover the gap and protect the brain in these patients; this citation probably reflected a widely known folk practice. Pietro d'Argellata introduced the use of a fixed piece of dried gourd for brain protection to reconstruct a skull defect. In the late Renaissance, the negative folklore describing this outlandish practice likely led to the use of silver and lead sheets. Nevertheless, for centuries, large numbers of surgeons preferred to leave the dura mater uncovered after bone removal, and failed to apply any brain protection. PMID:25403799

  19. Reconstruction of skull defects in the middle ages and renaissance.

    PubMed

    Missori, Paolo; Currà, Antonio; Paris, Harry S; Peschillo, Simone; Fattapposta, Francesco; Paolini, Sergio; Domenicucci, Maurizio

    2015-06-01

    In Egyptian, Greco-Roman, and Arabic medicine, the closure of a skull defect was not provided at the end of a therapeutic trepanation or in cases of bone removal. The literature from the Middle Ages and Renaissance disclosed some striking and forgotten practices. Gilbertus Anglicus (c. 1180 to c. 1250) cites the use of a piece of a cup made from wooden bowl (ciphum or mazer) or a gold sheet to cover the gap and protect the brain in these patients; this citation probably reflected a widely known folk practice. Pietro d'Argellata introduced the use of a fixed piece of dried gourd for brain protection to reconstruct a skull defect. In the late Renaissance, the negative folklore describing this outlandish practice likely led to the use of silver and lead sheets. Nevertheless, for centuries, large numbers of surgeons preferred to leave the dura mater uncovered after bone removal, and failed to apply any brain protection.

  20. The Ardipithecus ramidus skull and its implications for hominid origins.

    PubMed

    Suwa, Gen; Asfaw, Berhane; Kono, Reiko T; Kubo, Daisuke; Lovejoy, C Owen; White, Tim D

    2009-10-01

    The highly fragmented and distorted skull of the adult skeleton ARA-VP-6/500 includes most of the dentition and preserves substantial parts of the face, vault, and base. Anatomical comparisons and micro-computed tomography-based analysis of this and other remains reveal pre-Australopithecus hominid craniofacial morphology and structure. The Ardipithecus ramidus skull exhibits a small endocranial capacity (300 to 350 cubic centimeters), small cranial size relative to body size, considerable midfacial projection, and a lack of modern African ape-like extreme lower facial prognathism. Its short posterior cranial base differs from that of both Pan troglodytes and P. paniscus. Ar. ramidus lacks the broad, anteriorly situated zygomaxillary facial skeleton developed in later Australopithecus. This combination of features is apparently shared by Sahelanthropus, showing that the Mio-Pliocene hominid cranium differed substantially from those of both extant apes and Australopithecus.

  1. Comprehensive quality assurance for base of skull IMRT

    PubMed Central

    Thomas, A; O’Daniel, J; Adamovics, J; Ibbott, G; Oldham, M

    2013-01-01

    Six base of skull IMRT treatment plans were delivered to Presage dosimeters within the RPC Head and Neck Phantom for quality assurance (QA) verification. Isotropic 2mm 3D data were acquired by optical-CT scanning with the DLOS system (Duke Large Optical-CT Scanner) and compared to the Eclipse (Varian) treatment plan. Normalized Dose Distribution (NDD) pass rates were obtained for a number of criteria. High quality 3D dosimetry data was observed from the DLOS system, illustrated here through colormaps, isodose lines, and profiles. Excellent agreement with the planned dose distributions was also observed with NDD analysis revealing > 90% pass rates (with criteria 3%, 2mm), and noise < 0.5%. The results comprehensively confirm the high accuracy of base-of-skull IMRT treatment in our clinic. PMID:24567740

  2. Variation of BMP3 contributes to dog breed skull diversity.

    PubMed

    Schoenebeck, Jeffrey J; Hutchinson, Sarah A; Byers, Alexandra; Beale, Holly C; Carrington, Blake; Faden, Daniel L; Rimbault, Maud; Decker, Brennan; Kidd, Jeffrey M; Sood, Raman; Boyko, Adam R; Fondon, John W; Wayne, Robert K; Bustamante, Carlos D; Ciruna, Brian; Ostrander, Elaine A

    2012-01-01

    Since the beginnings of domestication, the craniofacial architecture of the domestic dog has morphed and radiated to human whims. By beginning to define the genetic underpinnings of breed skull shapes, we can elucidate mechanisms of morphological diversification while presenting a framework for understanding human cephalic disorders. Using intrabreed association mapping with museum specimen measurements, we show that skull shape is regulated by at least five quantitative trait loci (QTLs). Our detailed analysis using whole-genome sequencing uncovers a missense mutation in BMP3. Validation studies in zebrafish show that Bmp3 function in cranial development is ancient. Our study reveals the causal variant for a canine QTL contributing to a major morphologic trait.

  3. Dental development of the Taung skull from computerized tomography.

    PubMed

    Conroy, G C; Vannier, M W

    Just over 60 years ago, Dart's description and analysis of the Taung child's skull triggered an intellectual revolution about human origins. Recently, several authors have suggested that one of the most significant hominid-like traits of australopithecines, delayed maturation, may not after all be valid. This is a radical departure from Mann's classic study of australopithecine maturation and palaeodemography based on dental eruption patterns. The resolution of this debate has important implications for the history of the biological and social evolution of the human species. In view of the controversies generated by recent studies, and particularly because the Taung skull is the type specimen of Australopithecus africanus, we have investigated the relevant anatomy of the Taung 'child' using computerized tomography. We conclude that the Taung 'child' shows some important dental maturational affinities with great apes, although as Dart noted, other hominid-like features are clearly present. PMID:3116435

  4. Streamlined, Inexpensive 3D Printing of the Brain and Skull

    PubMed Central

    Cash, Sydney S.

    2015-01-01

    Neuroimaging technologies such as Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) collect three-dimensional data (3D) that is typically viewed on two-dimensional (2D) screens. Actual 3D models, however, allow interaction with real objects such as implantable electrode grids, potentially improving patient specific neurosurgical planning and personalized clinical education. Desktop 3D printers can now produce relatively inexpensive, good quality prints. We describe our process for reliably generating life-sized 3D brain prints from MRIs and 3D skull prints from CTs. We have integrated a standardized, primarily open-source process for 3D printing brains and skulls. We describe how to convert clinical neuroimaging Digital Imaging and Communications in Medicine (DICOM) images to stereolithography (STL) files, a common 3D object file format that can be sent to 3D printing services. We additionally share how to convert these STL files to machine instruction gcode files, for reliable in-house printing on desktop, open-source 3D printers. We have successfully printed over 19 patient brain hemispheres from 7 patients on two different open-source desktop 3D printers. Each brain hemisphere costs approximately $3–4 in consumable plastic filament as described, and the total process takes 14–17 hours, almost all of which is unsupervised (preprocessing = 4–6 hr; printing = 9–11 hr, post-processing = <30 min). Printing a matching portion of a skull costs $1–5 in consumable plastic filament and takes less than 14 hr, in total. We have developed a streamlined, cost-effective process for 3D printing brain and skull models. We surveyed healthcare providers and patients who confirmed that rapid-prototype patient specific 3D models may help interdisciplinary surgical planning and patient education. The methods we describe can be applied for other clinical, research, and educational purposes. PMID:26295459

  5. Vascularised local and free flaps in anterior skull base reconstruction.

    PubMed

    Hoffmann, Thomas K; El Hindy, Nicolai; Müller, Oliver M; Schuler, Patrick J; Bergmann, Christoph; Hierner, Robert; Lehnerdt, Götz; Mattheis, Stefan; Wagenmann, Martin; Schipper, Jörg; Sure, Ulrich; Lang, Stephan; Hänggi, Daniel; Sandalcioglu, I Erol

    2013-03-01

    Lesions of the anterior skull base often require sufficient closure in order to prevent cerebrospinal fluid (CSF) leak, ascending infection and/or brain tissue prolapse. The transfer of devitalized autologous, allogenic or xenogeneic material is not always sufficient particularly not in larger defects or in the recurrent situation. Here the transfer of vascularised tissue seems to be more appropriate. The anterior skull base with various complex defects of 41 patients was reconstructed in an interdisciplinary setting by vascularised, autologous tissue transfer. Minor defects (<2.5 cm in max. diameter), generally occurring after extended endoscopic skull base approaches (n = 26, among those meningiomas, recurrent CSF fistulas, chordoma, chondroblastoma, metastasis, nasal fistula), were reconstructed by a local, vascularized pedicled mucosal flap of the lower turbinate (n = 3) or septum (n = 23). Patients with major defects (>2.5 cm in max. diameter, n = 15), comprising those with malignoma, meningoencephalocele, aneurysmatic bone cyst and trauma, were repaired by a "sandwich technique" with a combination of calvarian split and galea periosteum flap in 10 patients, in one case with a temporalis muscle flap, while in 4 further patients free vascularised radial forearm flaps were used for revision after multiple unsuccessful operations elsewhere. After a mean follow-up time of 30.5 months 38 of the 41 cases were successfully repaired with respect to prevention and treatment of CSF leakage or brain tissue prolapse, only 3 cases needed surgical revision. The reconstruction of the anterior skull base bearing complex lesions is feasible using vascularised, autologous local and also distal tissue transfer in a close interdisciplinary cooperation. PMID:22878359

  6. Streamlined, Inexpensive 3D Printing of the Brain and Skull.

    PubMed

    Naftulin, Jason S; Kimchi, Eyal Y; Cash, Sydney S

    2015-01-01

    Neuroimaging technologies such as Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) collect three-dimensional data (3D) that is typically viewed on two-dimensional (2D) screens. Actual 3D models, however, allow interaction with real objects such as implantable electrode grids, potentially improving patient specific neurosurgical planning and personalized clinical education. Desktop 3D printers can now produce relatively inexpensive, good quality prints. We describe our process for reliably generating life-sized 3D brain prints from MRIs and 3D skull prints from CTs. We have integrated a standardized, primarily open-source process for 3D printing brains and skulls. We describe how to convert clinical neuroimaging Digital Imaging and Communications in Medicine (DICOM) images to stereolithography (STL) files, a common 3D object file format that can be sent to 3D printing services. We additionally share how to convert these STL files to machine instruction gcode files, for reliable in-house printing on desktop, open-source 3D printers. We have successfully printed over 19 patient brain hemispheres from 7 patients on two different open-source desktop 3D printers. Each brain hemisphere costs approximately $3-4 in consumable plastic filament as described, and the total process takes 14-17 hours, almost all of which is unsupervised (preprocessing = 4-6 hr; printing = 9-11 hr, post-processing = <30 min). Printing a matching portion of a skull costs $1-5 in consumable plastic filament and takes less than 14 hr, in total. We have developed a streamlined, cost-effective process for 3D printing brain and skull models. We surveyed healthcare providers and patients who confirmed that rapid-prototype patient specific 3D models may help interdisciplinary surgical planning and patient education. The methods we describe can be applied for other clinical, research, and educational purposes.

  7. Lytic Complications after Skull Reconstruction Using GeneX®.

    PubMed

    Park, Jin-Hack; Suh, Sang-Jun; Lee, Yoon-Soo; Lee, Jeong-Ho; Ryu, Kee-Young; Kang, Dong-Gee

    2015-10-01

    Multiple methods and materials are available for bone defect reconstruction. Bone graft substitute is one of the materials used for reconstruction of bone defect and have been widely used recently. This report describes some cases about complications related to GeneX® which is introduced as mixture of calcium sulfate and β-tricalcium phosphate at manufacturer's official web site. It informed of 3 patients who suffered wound inflammation, serous cyst after using GeneX® for reconstructing skull defect. PMID:27169079

  8. Streamlined, Inexpensive 3D Printing of the Brain and Skull.

    PubMed

    Naftulin, Jason S; Kimchi, Eyal Y; Cash, Sydney S

    2015-01-01

    Neuroimaging technologies such as Magnetic Resonance Imaging (MRI) and Computed Tomography (CT) collect three-dimensional data (3D) that is typically viewed on two-dimensional (2D) screens. Actual 3D models, however, allow interaction with real objects such as implantable electrode grids, potentially improving patient specific neurosurgical planning and personalized clinical education. Desktop 3D printers can now produce relatively inexpensive, good quality prints. We describe our process for reliably generating life-sized 3D brain prints from MRIs and 3D skull prints from CTs. We have integrated a standardized, primarily open-source process for 3D printing brains and skulls. We describe how to convert clinical neuroimaging Digital Imaging and Communications in Medicine (DICOM) images to stereolithography (STL) files, a common 3D object file format that can be sent to 3D printing services. We additionally share how to convert these STL files to machine instruction gcode files, for reliable in-house printing on desktop, open-source 3D printers. We have successfully printed over 19 patient brain hemispheres from 7 patients on two different open-source desktop 3D printers. Each brain hemisphere costs approximately $3-4 in consumable plastic filament as described, and the total process takes 14-17 hours, almost all of which is unsupervised (preprocessing = 4-6 hr; printing = 9-11 hr, post-processing = <30 min). Printing a matching portion of a skull costs $1-5 in consumable plastic filament and takes less than 14 hr, in total. We have developed a streamlined, cost-effective process for 3D printing brain and skull models. We surveyed healthcare providers and patients who confirmed that rapid-prototype patient specific 3D models may help interdisciplinary surgical planning and patient education. The methods we describe can be applied for other clinical, research, and educational purposes. PMID:26295459

  9. Recurrent Giant Cell Tumor of Skull Combined with Multiple Aneurysms

    PubMed Central

    Kim, Dae Hwan

    2016-01-01

    Giant cell tumors are benign but locally invasive and frequently recur. Giant cell tumors of the skull are extremely rare. A patient underwent a surgery to remove a tumor, but the tumor recurred. Additionally, the patient developed multiple aneurysms. The patient underwent total tumor resection and trapping for the aneurysms, followed by radiotherapy. We report this rare case and suggest some possibilities for treating tumor growth combined with aneurysm development. PMID:27195256

  10. Whole-transcriptome analysis of chordoma of the skull base.

    PubMed

    Bell, Diana; Raza, Shaan M; Bell, Achim H; Fuller, Gregory N; DeMonte, Franco

    2016-10-01

    Fourteen skull base chordoma specimens and three normal specimens were microdissected from paraffin-embedded tissue. Pools of RNA from highly enriched preparations of these cell types were subjected to expression profiling using whole-transcriptome shotgun sequencing. Using strict criteria, 294 differentially expressed transcripts were found, with 28 % upregulated and 72 % downregulated. The transcripts were annotated using NCBI Entrez Gene and computationally analyzed with the Ingenuity Pathway Analysis program. From these significantly changed expressions, the analysis identified 222 cancer-related transcripts. These 294 differentially expressed genes and non-coding RNA transcripts provide here a set to specifically define skull base chordomas and to identify novel and potentially important targets for diagnosis, prognosis, and therapy of this cancer. Significance Genomic profiling to subtype skull base chordoma reveals potential candidates for specific biomarkers, with validation by IHC for selected candidates. The highly expressed developmental genes T, LMX1A, ZIC4, LHX4, and HOXA1 may be potential drivers of this disease.

  11. Does nasal echolocation influence the modularity of the mammal skull?

    PubMed

    Santana, S E; Lofgren, S E

    2013-11-01

    In vertebrates, changes in cranial modularity can evolve rapidly in response to selection. However, mammals have apparently maintained their pattern of cranial integration throughout their evolutionary history and across tremendous morphological and ecological diversity. Here, we use phylogenetic, geometric morphometric and comparative analyses to test the hypothesis that the modularity of the mammalian skull has been remodelled in rhinolophid bats due to the novel and critical function of the nasal cavity in echolocation. We predicted that nasal echolocation has resulted in the evolution of a third cranial module, the 'nasal dome', in addition to the braincase and rostrum modules, which are conserved across mammals. We also test for similarities in the evolution of skull shape in relation to habitat across rhinolophids. We find that, despite broad variation in the shape of the nasal dome, the integration of the rhinolophid skull is highly consistent with conserved patterns of modularity found in other mammals. Across their broad geographical distribution, cranial shape in rhinolophids follows two major divisions that could reflect adaptations to dietary and environmental differences in African versus South Asian distributions. Our results highlight the potential of a relatively simple modular template to generate broad morphological and functional variation in mammals.

  12. Ground truth data generation for skull-face overlay.

    PubMed

    Ibáñez, O; Cavalli, F; Campomanes-Álvarez, B R; Campomanes-Álvarez, C; Valsecchi, A; Huete, M I

    2015-05-01

    Objective and unbiased validation studies over a significant number of cases are required to get a more solid picture on craniofacial superimposition reliability. It will not be possible to compare the performance of existing and upcoming methods for craniofacial superimposition without a common forensic database available for the research community. Skull-face overlay is a key task within craniofacial superimposition that has a direct influence on the subsequent task devoted to evaluate the skull-face relationships. In this work, we present the procedure to create for the first time such a dataset. We have also created a database with 19 skull-face overlay cases for which we are trying to overcome legal issues that allow us to make it public. The quantitative analysis made in the segmentation and registration stages, together with the visual assessment of the 19 face-to-face overlays, allows us to conclude that the results can be considered as a gold standard. With such a ground truth dataset, a new horizon is opened for the development of new automatic methods whose performance could be now objectively measured and compared against previous and future proposals. Additionally, other uses are expected to be explored to better understand the visual evaluation process of craniofacial relationships in craniofacial identification. It could be very useful also as a starting point for further studies on the prediction of the resulting facial morphology after corrective or reconstructive interventionism in maxillofacial surgery.

  13. Morphometric analysis of infraorbital foramen in Indian dry skulls

    PubMed Central

    2011-01-01

    We analyzed the variability in position, shape, size and incidence of the infraorbital foramen in Indian dry skulls as little literature is available on this foramen in Indians to prevent clinical complications during maxillofacial surgery and regional block anesthesia. Fifty-five Indian skulls from the Department of Anatomy CSM Medical University were examined. The 110 sides (left and right) of the skulls were analyzed by measuring the infraorbital foramina distances from infraorbital margin and the piriform aperture on both sides. The vertical and horizontal dimensions were also measured. All measurements were taken with a compass transferred to calipers and analyzed statistically. The mean distances between the infraorbital foramen and the infraorbital margin on the right and left side were 6.12 mm and 6.19 mm, respectively. The mean distances between the infraorbital foramen and the piriform aperture were 15.31 mm and 15.80 mm on the right and left sides, respectively. The mean vertical dimensions on the right and left side were 3.39 mm and 3.75 mm, respectively. The mean horizontal dimensions on the two sides were 3.19 mm and 3.52 mm. These results provide detailed knowledge of the anatomical characteristics and clinical importance of the infraorbital foramina which are of paramount importance for surgeons when performing maxillofacial surgery and regional block anesthesia. PMID:21519552

  14. Shape similarities and differences in the skulls of scavenging raptors.

    PubMed

    Guangdi, S I; Dong, Yiyi; Ma, Yujun; Zhang, Zihui

    2015-04-01

    Feeding adaptations are a conspicuous feature of avian evolution. Bill and cranial shape as well as the jaw muscles are closely related to diet choice and feeding behaviors. Diurnal raptors of Falconiformes exhibit a wide range of foraging behaviors and prey preferences, and are assigned to seven dietary groups in this study. Skulls of 156 species are compared from the dorsal, lateral and ventral views, by using geometric morphometric techniques with those landmarks capturing as much information as possible on the overall shape of cranium, bill, orbits, nostrils and attachment area for different jaw muscles. The morphometric data showed that the skull shape of scavengers differ significantly from other raptors, primarily because of different feeding adaptations. As a result of convergent evolution, different scavengers share generalized common morphology, possessing relatively slender and lower skulls, longer bills, smaller and more sideward orbits, and more caudally positioned quadrates. Significant phylogenetic signals suggested that phylogeny also played important role in shape variation within scavengers. New World vultures can be distinguished by their large nostrils, narrow crania and small orbits; Caracaras typically show large palatines, crania and orbits, as well as short, deep and sharp bill. PMID:25826066

  15. Extreme variations in skull density of toadfish, Opsanus ta

    NASA Astrophysics Data System (ADS)

    Edds-Walton, Peggy; Ketten, Darlene

    2003-10-01

    Gross observations of the skull in sexually mature toadfish revealed variations in bone density that appear to be most extreme in the otic capsule. Four male and one female toadfish (17-30.5 cm SL) were scanned to obtain images formatted at 100 μm and 1 mm. Consecutive measurements were made from caudal of the otic capsule to the rostral edge of the otic capsule. Attenuation values were recorded from three sites on the skull (left parietal bone, parietal suture, ventral surface of the otic capsule) and along two otoliths (calcareous, associated with the sensory epithelia of the ear) within the otic capsule. In all five fish, the parietal suture had the highest attenuation. Attenuation values for the parietal bone varied with size, indicating increasing density with growth. Among all five fish, the lowest attenuations were obtained for the ventral wall of the otic capsule, with values similar to those of cartilage. In addition, the minimum values were found ventral to the saccular otolith. Given that the saccule is the primary auditory endorgan in this species [Edds-Walton et al., J. Comp. Neurol. 411, 212-238 (1999)], the co-occurrence of bone thinning in this area of the skull may have functional significance related to audition.

  16. Morphometry of the Greater Palatal Canal in Adult Skulls.

    PubMed

    Soto, Reinaldo A; Cáceres, Felipe; Vera, Cristóbal

    2015-07-01

    The purpose of this study was to evaluate in dry skulls the length and angle between the greater palatine foramen and the foramen rotundum in both the frontal and sagittal planes. In 50 human skulls from the department of morphology, the distance and angulation required to reach the foramen rotundum through the greater palatine canal were measured in the frontal and sagittal planes. A stylet was introduced up to the foramen rotundum in each greater palatine canal and fixed. The skulls were then photographed from a front and lateral view (both right and left). Finally, the stylets were photographed on graph paper. These images were analyzed with Photoshop software. In the frontal plane, mean angulations of 5.32 degrees on the right side and 6.15 degrees on the left side were obtained. In the sagittal plane, mean angulations of 61.66 degrees on the right side and 61.81 degrees on the left side were obtained. Finally, the mean length required to reach the foramen rotundum was 31.95  mm on the right side and 32.49  mm on the left side. Some of these results differ from those stated in the foreign literature (10 degrees front, 70 degrees sagittal). These differences should be considered for both clinical practice and teaching in Chile.

  17. The use of free flaps in skull base reconstruction.

    PubMed

    Macía, G; Picón, M; Nuñez, J; Almeida, F; Alvarez, I; Acero, J

    2016-02-01

    Skull base tumours are rare, comprising less than 1% of all tumours of the head and neck. Surgical treatment of these tumours involves the approach, the resection, and the reconstruction of the defect, which present a challenge due to the technical difficulty and anatomical complexity. A retrospective study of 17 patients with tumours involving the skull base, treated by resection and immediate reconstruction using microsurgical free flaps, is presented; 11 were men and six were women. The following types of flap were used: osteocutaneous fibula flaps, fasciocutaneous anterolateral thigh flaps, and myocutaneous latissimus dorsi flaps. The most common histology of the tumours was squamous cell carcinoma. The most frequent point of origin was the paranasal sinuses (58.8%). All of the free flaps used for reconstruction were viable. A cerebrospinal fluid fistula occurred in two patients, and in one of these cases, meningoencephalitis led to death. In conclusion, the reconstruction of large defects of the skull base after ablation requires a viable tissue that in many cases can be obtained only through the use of microvascular free flaps. The type of flap to be selected depends on the anatomical structures and size of the defect to be restored.

  18. Ground truth data generation for skull-face overlay.

    PubMed

    Ibáñez, O; Cavalli, F; Campomanes-Álvarez, B R; Campomanes-Álvarez, C; Valsecchi, A; Huete, M I

    2015-05-01

    Objective and unbiased validation studies over a significant number of cases are required to get a more solid picture on craniofacial superimposition reliability. It will not be possible to compare the performance of existing and upcoming methods for craniofacial superimposition without a common forensic database available for the research community. Skull-face overlay is a key task within craniofacial superimposition that has a direct influence on the subsequent task devoted to evaluate the skull-face relationships. In this work, we present the procedure to create for the first time such a dataset. We have also created a database with 19 skull-face overlay cases for which we are trying to overcome legal issues that allow us to make it public. The quantitative analysis made in the segmentation and registration stages, together with the visual assessment of the 19 face-to-face overlays, allows us to conclude that the results can be considered as a gold standard. With such a ground truth dataset, a new horizon is opened for the development of new automatic methods whose performance could be now objectively measured and compared against previous and future proposals. Additionally, other uses are expected to be explored to better understand the visual evaluation process of craniofacial relationships in craniofacial identification. It could be very useful also as a starting point for further studies on the prediction of the resulting facial morphology after corrective or reconstructive interventionism in maxillofacial surgery. PMID:25267257

  19. Whole-transcriptome analysis of chordoma of the skull base.

    PubMed

    Bell, Diana; Raza, Shaan M; Bell, Achim H; Fuller, Gregory N; DeMonte, Franco

    2016-10-01

    Fourteen skull base chordoma specimens and three normal specimens were microdissected from paraffin-embedded tissue. Pools of RNA from highly enriched preparations of these cell types were subjected to expression profiling using whole-transcriptome shotgun sequencing. Using strict criteria, 294 differentially expressed transcripts were found, with 28 % upregulated and 72 % downregulated. The transcripts were annotated using NCBI Entrez Gene and computationally analyzed with the Ingenuity Pathway Analysis program. From these significantly changed expressions, the analysis identified 222 cancer-related transcripts. These 294 differentially expressed genes and non-coding RNA transcripts provide here a set to specifically define skull base chordomas and to identify novel and potentially important targets for diagnosis, prognosis, and therapy of this cancer. Significance Genomic profiling to subtype skull base chordoma reveals potential candidates for specific biomarkers, with validation by IHC for selected candidates. The highly expressed developmental genes T, LMX1A, ZIC4, LHX4, and HOXA1 may be potential drivers of this disease. PMID:27401718

  20. Metric analysis of basal sphenoid angle in adult human skulls

    PubMed Central

    Netto, Dante Simionato; Nascimento, Sergio Ricardo Rios; Ruiz, Cristiane Regina

    2014-01-01

    Objective To analyze the variations in the angle basal sphenoid skulls of adult humans and their relationship to sex, age, ethnicity and cranial index. Methods The angles were measured in 160 skulls belonging to the Museum of the Universidade Federal de São Paulo Department of Morphology. We use two flexible rules and a goniometer, having as reference points for the first rule the posterior end of the ethmoidal crest and dorsum of the sella turcica, and for the second rule the anterior margin of the foramen magnum and clivus, measuring the angle at the intersection of two. Results The average angle was 115.41°, with no statistical correlation between the value of the angle and sex or age. A statistical correlation was noted between the value of the angle and ethnicity, and between the angle and the horizontal cranial index. Conclusions The distribution of the angle basal sphenoid was the same in sex, and there was correlation between the angle and ethnicity, being the proportion of non-white individuals with an angle >125° significantly higher than that of whites with an angle >125°. There was correlation between the angle and the cranial index, because skulls with higher cranial index tend to have higher basiesfenoidal angle too. PMID:25295452

  1. Surgeon's view of the skull base from the lateral approach.

    PubMed

    Goldenberg, R A

    1984-12-01

    This paper presents the surgical anatomy of the skull base and infratemporal fossa. The information has been derived from the author's own experience in surgical and cadaver dissection, standard anatomical references, and selected experience of other skull base surgeons. Because the lateral approach has become the utilitarian method of exposure, the intricate detailed anatomy is demonstrated from this view at five levels of dissection, so the surgeon may gain a practical understanding of the surgical relationship of critical structures. Consistent anatomical landmarks can be used by the surgeon in the location of these critical structures. The styloid process, sphenoidal spine, and middle meningeal artery identify the internal carotid artery as it enters the carotid canal. The bony or fibrous septum that divides the jugular foramen into neural and vascular compartments may be used to better identify nerves IX, X, and XI. The zygomatic root is useful for location of the middle fossa dura. The lateral pterygoid plate leads directly to the foramen ovale. The increased precision of dissection permitted by use of the microscope requires an increased level of knowledge of anatomical structures in this area. It is hoped that the information presented in this paper will assist surgeons in the meticulous and thorough removal of skull base tumors and in the preservation of neural and vascular structures that are presently being sacrificed.

  2. Assessment of the role of sutures in a lizard skull: a computer modelling study

    PubMed Central

    Moazen, Mehran; Curtis, Neil; O'Higgins, Paul; Jones, Marc E.H; Evans, Susan E; Fagan, Michael J

    2008-01-01

    Sutures form an integral part of the functioning skull, but their role has long been debated among vertebrate morphologists and palaeontologists. Furthermore, the relationship between typical skull sutures, and those involved in cranial kinesis, is poorly understood. In a series of computational modelling studies, complex loading conditions obtained through multibody dynamics analysis were imposed on a finite element model of the skull of Uromastyx hardwickii, an akinetic herbivorous lizard. A finite element analysis (FEA) of a skull with no sutures revealed higher patterns of strain in regions where cranial sutures are located in the skull. From these findings, FEAs were performed on skulls with sutures (individual and groups of sutures) to investigate their role and function more thoroughly. Our results showed that individual sutures relieved strain locally, but only at the expense of elevated strain in other regions of the skull. These findings provide an insight into the behaviour of sutures and show how they are adapted to work together to distribute strain around the skull. Premature fusion of one suture could therefore lead to increased abnormal loading on other regions of the skull causing irregular bone growth and deformities. This detailed investigation also revealed that the frontal–parietal suture of the Uromastyx skull played a substantial role in relieving strain compared with the other sutures. This raises questions about the original role of mesokinesis in squamate evolution. PMID:18765341

  3. Assessment of the role of sutures in a lizard skull: a computer modelling study.

    PubMed

    Moazen, Mehran; Curtis, Neil; O'Higgins, Paul; Jones, Marc E H; Evans, Susan E; Fagan, Michael J

    2009-01-01

    Sutures form an integral part of the functioning skull, but their role has long been debated among vertebrate morphologists and palaeontologists. Furthermore, the relationship between typical skull sutures, and those involved in cranial kinesis, is poorly understood. In a series of computational modelling studies, complex loading conditions obtained through multibody dynamics analysis were imposed on a finite element model of the skull of Uromastyx hardwickii, an akinetic herbivorous lizard. A finite element analysis (FEA) of a skull with no sutures revealed higher patterns of strain in regions where cranial sutures are located in the skull. From these findings, FEAs were performed on skulls with sutures (individual and groups of sutures) to investigate their role and function more thoroughly. Our results showed that individual sutures relieved strain locally, but only at the expense of elevated strain in other regions of the skull. These findings provide an insight into the behaviour of sutures and show how they are adapted to work together to distribute strain around the skull. Premature fusion of one suture could therefore lead to increased abnormal loading on other regions of the skull causing irregular bone growth and deformities. This detailed investigation also revealed that the frontal-parietal suture of the Uromastyx skull played a substantial role in relieving strain compared with the other sutures. This raises questions about the original role of mesokinesis in squamate evolution.

  4. Is solid always best? Cranial performance in solid and fenestrated caecilian skulls.

    PubMed

    Kleinteich, Thomas; Maddin, Hillary C; Herzen, Julia; Beckmann, Felix; Summers, Adam P

    2012-03-01

    Caecilians (Lissamphibia: Gymnophiona) are characterized by a fossorial lifestyle that appears to play a role in the many anatomical specializations in the group. The skull, in particular, has been the focus of previous studies because it is driven into the substrate for burrowing. There are two different types of skulls in caecilians: (1) stegokrotaphic, where the squamosal completely covers the temporal region and the jaw closing muscles, and (2) zygokrotaphic, with incomplete coverage of the temporal region by the squamosal. We used 3-D imaging and modeling techniques to explore the functional consequences of these skull types in an evolutionary context. We digitally converted stegokrotaphic skulls into zygokrotaphic skulls and vice versa. We also generated a third, akinetic skull type that was presumably present in extinct caecilian ancestors. We explored the benefits and costs of the different skull types under frontal loading at different head angles with finite element analysis (FEA). Surprisingly, the differences in stress distributions and bending between the three tested skull types were minimal and not significant. This suggests that the open temporal region in zygokrotaphic skulls does not lead to poorer performance during burrowing. However, the results of the FEA suggest a strong relationship between the head angle and skull performance, implying there is an optimal head angle during burrowing.

  5. Is solid always best? Cranial performance in solid and fenestrated caecilian skulls.

    PubMed

    Kleinteich, Thomas; Maddin, Hillary C; Herzen, Julia; Beckmann, Felix; Summers, Adam P

    2012-03-01

    Caecilians (Lissamphibia: Gymnophiona) are characterized by a fossorial lifestyle that appears to play a role in the many anatomical specializations in the group. The skull, in particular, has been the focus of previous studies because it is driven into the substrate for burrowing. There are two different types of skulls in caecilians: (1) stegokrotaphic, where the squamosal completely covers the temporal region and the jaw closing muscles, and (2) zygokrotaphic, with incomplete coverage of the temporal region by the squamosal. We used 3-D imaging and modeling techniques to explore the functional consequences of these skull types in an evolutionary context. We digitally converted stegokrotaphic skulls into zygokrotaphic skulls and vice versa. We also generated a third, akinetic skull type that was presumably present in extinct caecilian ancestors. We explored the benefits and costs of the different skull types under frontal loading at different head angles with finite element analysis (FEA). Surprisingly, the differences in stress distributions and bending between the three tested skull types were minimal and not significant. This suggests that the open temporal region in zygokrotaphic skulls does not lead to poorer performance during burrowing. However, the results of the FEA suggest a strong relationship between the head angle and skull performance, implying there is an optimal head angle during burrowing. PMID:22323206

  6. Immediate, but Not Delayed, Microsurgical Skull Reconstruction Exacerbates Brain Damage in Experimental Traumatic Brain Injury Model

    PubMed Central

    Lau, Tsz; Kaneko, Yuji; van Loveren, Harry; Borlongan, Cesario V.

    2012-01-01

    Moderate to severe traumatic brain injury (TBI) often results in malformations to the skull. Aesthetic surgical maneuvers may offer normalized skull structure, but inconsistent surgical closure of the skull area accompanies TBI. We examined whether wound closure by replacement of skull flap and bone wax would allow aesthetic reconstruction of the TBI-induced skull damage without causing any detrimental effects to the cortical tissue. Adult male Sprague-Dawley rats were subjected to TBI using the controlled cortical impact (CCI) injury model. Immediately after the TBI surgery, animals were randomly assigned to skull flap replacement with or without bone wax or no bone reconstruction, then were euthanized at five days post-TBI for pathological analyses. The skull reconstruction provided normalized gross bone architecture, but 2,3,5-triphenyltetrazolium chloride and hematoxylin and eosin staining results revealed larger cortical damage in these animals compared to those that underwent no surgical maneuver at all. Brain swelling accompanied TBI, especially the severe model, that could have relieved the intracranial pressure in those animals with no skull reconstruction. In contrast, the immediate skull reconstruction produced an upregulation of the edema marker aquaporin-4 staining, which likely prevented the therapeutic benefits of brain swelling and resulted in larger cortical infarcts. Interestingly, TBI animals introduced to a delay in skull reconstruction (i.e., 2 days post-TBI) showed significantly reduced edema and infarcts compared to those exposed to immediate skull reconstruction. That immediate, but not delayed, skull reconstruction may exacerbate TBI-induced cortical tissue damage warrants a careful consideration of aesthetic repair of the skull in TBI. PMID:22438975

  7. Arcuate Fractures

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site]

    In the upper left corner of this VIS image are a series of fractures. Where the fractures are exposed on the surface it is impossible to tell the plane of the fracture; however where the fractures are visible in the cliff wall it is possible to see that the fractures dip to the north. This image shows part of the caldera of Tharsis Tholus.

    Image information: VIS instrument. Latitude 1.7, Longitude 176.5 East (183.5 West). 19 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  8. Experimental and theoretical strain distributions for stationary and growing cracks

    NASA Astrophysics Data System (ADS)

    Gerberich, W. W.; Davidson, D. L.; Kaczorowski, M.

    E XPERIMENTAL strain distributions are determined very near the crack tip in Fe-3wt.%Si single crystals. Both in situ stereoimaging and electron channeling techniques give reasonably reproducible distributions. By growing fatigue cracks on a {100} cleavage plane, the singularity strengths have been determined for both growing and stationary cracks under relatively plane stress and plane strain conditions. This has allowed a comparison to existing theoretical models. It is shown that the HRR singularity (Hutchinson, Rice and Rosengren, 1968) for stationary cracks is very good to within I μm of the crack tip and a hardening model for the growing crack (gao and hwang, Advances in Fracture Research, edited by D. Francois. 5th Int. Conf. on Fracture, Cannes, France, 2, 669, 1981) is surprisingly good. Other issues such as fracture criteria are discussed since strains greater than unity were measured at the crack tip in this relatively brittle material.

  9. Divergent Skull Morphology Supports Two Trophic Specializations in Otters (Lutrinae).

    PubMed

    Timm-Davis, Lori L; DeWitt, Thomas J; Marshall, Christopher D

    2015-01-01

    Variation in terrestrial mammalian skull morphology is known to constrain feeding performance, which in turn influences dietary habits and ultimately fitness. Among mustelids, otters have evolved two feeding specializations: underwater raptorial capture of prey (mouth-oriented) and capture of prey by hand (hand-oriented), both of which have likely associations with morphology and bite performance. However, feeding biomechanics and performance data for otters are sparse. The first goal of this study was to investigate the relationships between feeding morphology and bite performance among two mouth-oriented piscivores (Pteronura brasiliensis and Lontra canadensis) and two hand-oriented invertebrate specialists (Enhydra lutris and Aonyx cinerea). Since other vertebrate taxa that are mouth-oriented piscivores tend to possess longer skulls and mandibles, with jaws designed for increased velocity at the expense of biting capability, we hypothesized that mouth-oriented otters would also possess long, narrow skulls indicative of high velocity jaws. Conversely, hand-oriented otters were expected to possess short, blunt skulls with adaptations to increase bite force and crushing capability. Concomitant with these skull shapes we hypothesized that sea otters would possess a greater mandibular bluntness index, providing for a greater mechanical advantage compared to other otter species investigated. A second goal was to examine morphological variation at a finer scale by assessing variation in cranial morphology among three sea otter subspecies. Since diet varies among these subspecies, and their populations are isolated, we hypothesized that the magnitude of mandibular bluntness and concomitant mechanical advantage, as well as occlusal surface area would also vary within species according to their primary food source (fish versus hard invertebrates). Functional expectations were met for comparisons among and within species. Among species the phylogeny suggests a deeply

  10. Micrometeorite Impacts in Beringian Mammoth Tusks and a Bison Skull

    NASA Astrophysics Data System (ADS)

    Firestone, R. B.; West, A.; Stefanka, Z.; Revay, Z.; Hagstrum, J. T.

    2007-12-01

    We have discovered what appear to be micrometeorites imbedded in seven Alaskan Mammoth tusks and a Siberian bison skull. The micrometeorites apparently shattered on impact leaving 2-5 mm hemispherical debris patterns surrounded by carbonized rings. Multiple impacts are observed on only one side of the tusks and skull consistent with the micrometeorites having come from a single direction. The impact sites are strongly magnetic indicating significant iron content. We analyzed several imbedded micrometeorite fragments from both tusks and skull with Laser Ablation Inductively-Coupled Plasma Mass Spectrometry (LA-ICP-MS) and X-ray Fluorescence (XRF). These analyses confirmed the high iron content and a uniform composition highly enriched in nickel and depleted in titanium. The Fe/Ni and Fe/Ti ratios are comparable to urelite meteorites and are unlike any terrestrial sources. Prompt Gamma-ray Activation Analysis (PGAA) of a micrometeorite extracted from the bison skull indicated it contained ~0.4 mg of iron, in agreement with a micrometeorite ~1 mm in diameter. Several tusks have an average radiocarbon age of ~33 ka. This age coincides with sudden increases in global radiocarbon ~35 ka agoa and 10Be ~32 ka agob, the Mono Lake geomagnetic excursion ~34 ka agoc, and significant declines in Beringian bison, horse, brown bear, and mammoth populations and genetic diversity <36 ka agod. The bison skull shows evidence of new bone growth over the micrometeorite impact sites indicating the animal survived the bombardment and is dated at ~26 ka which is younger than the tusks. This age is consistent with exposure of the bison to an enriched source of radiocarbon following the impact. It appears likely that the impacts, cosmogenic isotope increases, magnetic excursion, and population declines are related events (Occam's razor), although their precise nature remains to be determined. aK. Hughen, et al., Science 303, 202-207 (2004). bL.R. McHargue, P.E. Damon, & D.J. Donahue

  11. Divergent Skull Morphology Supports Two Trophic Specializations in Otters (Lutrinae)

    PubMed Central

    Timm-Davis, Lori L.; DeWitt, Thomas J.; Marshall, Christopher D.

    2015-01-01

    Variation in terrestrial mammalian skull morphology is known to constrain feeding performance, which in turn influences dietary habits and ultimately fitness. Among mustelids, otters have evolved two feeding specializations: underwater raptorial capture of prey (mouth-oriented) and capture of prey by hand (hand-oriented), both of which have likely associations with morphology and bite performance. However, feeding biomechanics and performance data for otters are sparse. The first goal of this study was to investigate the relationships between feeding morphology and bite performance among two mouth-oriented piscivores (Pteronura brasiliensis and Lontra canadensis) and two hand-oriented invertebrate specialists (Enhydra lutris and Aonyx cinerea). Since other vertebrate taxa that are mouth-oriented piscivores tend to possess longer skulls and mandibles, with jaws designed for increased velocity at the expense of biting capability, we hypothesized that mouth-oriented otters would also possess long, narrow skulls indicative of high velocity jaws. Conversely, hand-oriented otters were expected to possess short, blunt skulls with adaptations to increase bite force and crushing capability. Concomitant with these skull shapes we hypothesized that sea otters would possess a greater mandibular bluntness index, providing for a greater mechanical advantage compared to other otter species investigated. A second goal was to examine morphological variation at a finer scale by assessing variation in cranial morphology among three sea otter subspecies. Since diet varies among these subspecies, and their populations are isolated, we hypothesized that the magnitude of mandibular bluntness and concomitant mechanical advantage, as well as occlusal surface area would also vary within species according to their primary food source (fish versus hard invertebrates). Functional expectations were met for comparisons among and within species. Among species the phylogeny suggests a deeply

  12. Divergent Skull Morphology Supports Two Trophic Specializations in Otters (Lutrinae).

    PubMed

    Timm-Davis, Lori L; DeWitt, Thomas J; Marshall, Christopher D

    2015-01-01

    Variation in terrestrial mammalian skull morphology is known to constrain feeding performance, which in turn influences dietary habits and ultimately fitness. Among mustelids, otters have evolved two feeding specializations: underwater raptorial capture of prey (mouth-oriented) and capture of prey by hand (hand-oriented), both of which have likely associations with morphology and bite performance. However, feeding biomechanics and performance data for otters are sparse. The first goal of this study was to investigate the relationships between feeding morphology and bite performance among two mouth-oriented piscivores (Pteronura brasiliensis and Lontra canadensis) and two hand-oriented invertebrate specialists (Enhydra lutris and Aonyx cinerea). Since other vertebrate taxa that are mouth-oriented piscivores tend to possess longer skulls and mandibles, with jaws designed for increased velocity at the expense of biting capability, we hypothesized that mouth-oriented otters would also possess long, narrow skulls indicative of high velocity jaws. Conversely, hand-oriented otters were expected to possess short, blunt skulls with adaptations to increase bite force and crushing capability. Concomitant with these skull shapes we hypothesized that sea otters would possess a greater mandibular bluntness index, providing for a greater mechanical advantage compared to other otter species investigated. A second goal was to examine morphological variation at a finer scale by assessing variation in cranial morphology among three sea otter subspecies. Since diet varies among these subspecies, and their populations are isolated, we hypothesized that the magnitude of mandibular bluntness and concomitant mechanical advantage, as well as occlusal surface area would also vary within species according to their primary food source (fish versus hard invertebrates). Functional expectations were met for comparisons among and within species. Among species the phylogeny suggests a deeply

  13. Transcranial Direct Current Stimulation in Patients with Skull Defects and Skull Plates: High-Resolution Computational FEM Study of Factors Altering Cortical Current Flow

    PubMed Central

    Datta, Abhishek; Bikson, Marom; Fregni, Felipe

    2010-01-01

    Preliminary positive results of transcranial direct current stimulation (tDCS) in enhancing the effects of cognitive and motor training indicate this technique might also be beneficial in traumatic brain injury or patients who had decompressive craniectomy for trauma and cerebrovascular disease. One perceived hurdle is the presence of skull defects or skull plates in these patients that would hypothetically alter the intensity and location of current flow through the brain. We aimed to model tDCS using a magnetic resonance imaging (MRI)-derived finite element head model with several conceptualized skull injuries. Cortical electric field (current density) peak intensities and distributions were compared with the healthy (skull intact) case. The factors of electrode position (C3-supraorbital or O1-supraorbital), skull defect size, skull defect state (acute and chronic) or skull plate (titanium and acrylic) were analyzed. If and how electric current through the brain was modulated by defects was found to depend on a specific combination of factors. For example, the condition that led to largest increase in peak cortical electric field was when one electrode was placed directly over a moderate sized skull defect. In contrast, small defects midway between electrodes did not significantly change cortical currents. As the conductivity of large skull defects/plates was increased (chronic to acute to titanium), current was shunted away from directly underlying cortex and concentrated in cortex underlying the defect perimeter. The predictions of this study are the first step to assess safety of transcranial electrical therapy in subjects with skull injuries. PMID:20435146

  14. Material properties of human infant skull and suture at high rates.

    PubMed

    Coats, Brittany; Margulies, Susan S

    2006-08-01

    Clinicians are often faced with the challenging task of distinguishing between accidental and inflicted pediatric head trauma. There is currently a disparity in the anecdotal case study literature as to what kinds of injuries can occur in children from low height falls. There is also a paucity of material property data for pediatric skull and suture at rates similar to those expected in low height falls. We tested human infant (<1 year old) cranial bone and suture from 23 calveria in three-point bending and tension, respectively, at rates ranging from 1.2-2.8 m/sec. Donor age was found to have the largest influence on the elastic modulus and ultimate stress of cranial bone, with an increase in age increasing both material properties. In adults, cranial bone and suture have similar properties and the adult calveria deforms very little prior to fracture. In contrast, pediatric cranial bone is 35 times stiffer than pediatric cranial suture. In addition, pediatric cranial suture deforms 30 times more before failure than pediatric cranial bone and 243 times more than adult cranial bone. The large strains in the pediatric bone and suture result in a skullcase that can undergo dramatic shape changes before fracture, potentially causing substantial deformation in the brain. The sizeable difference between pediatric bone and suture material properties also underscores the crucial role that sutures play in the unique response of the pediatric head to impact in low height falls. These data provide necessary information to enhance our understanding of mechanisms of head injury in young children.

  15. Application of thinned-skull cranial window to mouse cerebral blood flow imaging using optical microangiography.

    PubMed

    Li, Yuandong; Baran, Utku; Wang, Ruikang K

    2014-01-01

    In vivo imaging of mouse brain vasculature typically requires applying skull window opening techniques: open-skull cranial window or thinned-skull cranial window. We report non-invasive 3D in vivo cerebral blood flow imaging of C57/BL mouse by the use of ultra-high sensitive optical microangiography (UHS-OMAG) and Doppler optical microangiography (DOMAG) techniques to evaluate two cranial window types based on their procedures and ability to visualize surface pial vessel dynamics. Application of the thinned-skull technique is found to be effective in achieving high quality images for pial vessels for short-term imaging, and has advantages over the open-skull technique in available imaging area, surgical efficiency, and cerebral environment preservation. In summary, thinned-skull cranial window serves as a promising tool in studying hemodynamics in pial microvasculature using OMAG or other OCT blood flow imaging modalities.

  16. Atypical culture-negative skull base osteomyelitis masquerading as advanced nasopharyngeal carcinoma.

    PubMed

    See, Anna; Tan, Tiong Yong; Gan, Eng Cern

    2016-01-01

    Skull base osteomyelitis typically arises as a complication of otogenic or sinonasal infections in immunocompromised patients. A much rarer entity, atypical skull base osteomyelitis is not associated with an obvious infective source. Atypical and culture-negative skull base osteomyelitis is even rarer and hampers diagnosis, as its clinical presentation is remarkably similar to skull base neoplasms. We report a case of extensive skull base osteomyelitis with orbital apex syndrome and multiple lower cranial nerve palsies which initially masqueraded as possible advanced nasopharyngeal carcinoma. Extensive investigations and consult with an infectious diseases specialist aided in elucidation of the correct diagnosis. Through this article, we emphasize that skull base osteomyelitis must be considered in the setting of headache, cranial neuropathies, elevated inflammatory markers and abnormal imaging findings. Early tissue sampling for histology, stainings and cultures and prompt appropriate treatment may prevent or arrest further complications. PMID:27178515

  17. Application of Thinned-Skull Cranial Window to Mouse Cerebral Blood Flow Imaging Using Optical Microangiography

    PubMed Central

    Wang, Ruikang K.

    2014-01-01

    In vivo imaging of mouse brain vasculature typically requires applying skull window opening techniques: open-skull cranial window or thinned-skull cranial window. We report non-invasive 3D in vivo cerebral blood flow imaging of C57/BL mouse by the use of ultra-high sensitive optical microangiography (UHS-OMAG) and Doppler optical microangiography (DOMAG) techniques to evaluate two cranial window types based on their procedures and ability to visualize surface pial vessel dynamics. Application of the thinned-skull technique is found to be effective in achieving high quality images for pial vessels for short-term imaging, and has advantages over the open-skull technique in available imaging area, surgical efficiency, and cerebral environment preservation. In summary, thinned-skull cranial window serves as a promising tool in studying hemodynamics in pial microvasculature using OMAG or other OCT blood flow imaging modalities. PMID:25426632

  18. Demonstration of skull bones mobility using optical methods: practical importance in medicine

    NASA Astrophysics Data System (ADS)

    Zakharov, Alexander V.; Okushko, Vladimir R.; Vturin, Sergey A.; Moseychuk, Vladimir V.; Petrov, Aleksey A.; Suetenkov, Dmitry E.

    2014-01-01

    Unprompted skull bones mobility not related to breathing, heart beating and other physiological reactions, using installation of original construction with control of physiological parameters by biofeedback hardware-software complex BOS-lab and BOS-pulse appliance (COMSIB, Novosibirsk, Russia) has been confirmed. Teeth eruption occurs through odontiasis canals, emerging from the funiculus. The main driving force for promoting a tooth into odontiasis canal during eruption is the unprompted skull bones mobility. A simple optical installation was made for the visualization of skull bones mobility during the investigation of the median palatine and incisors sutures. Early detection of failures of unprompted skull bones mobility and its normalization can lead to prevention of impact teeth, malocclusion, extrudocclusion and other anomalies and deformations of teeth, teeth rows, TMJ and skull. The skull bones mobility should be considered during the early preventive treatment and therapy of the consequences of injuries and malfunction of the maxillofacial area.

  19. Apparatus for growing crystals

    NASA Technical Reports Server (NTRS)

    Jasinski, Thomas J. (Inventor); Witt, August F. (Inventor)

    1986-01-01

    An improved apparatus and method for growing crystals from a melt employing a heat pipe, consisting of one or more sections, each section serving to control temperature and thermal gradients in the crystal as it forms inside the pipe.

  20. How Your Baby Grows

    MedlinePlus

    ... brain, the heart and lungs, are forming. The placenta grows in your uterus and supplies the baby ... like alcohol, cigarette smoke and drugs through the placenta, too. So don’t drink alcohol , smoke , use ...

  1. Plain skull film radiography in the management of head trauma: an overview

    SciTech Connect

    McClean, P.M.; Joseph, L.P.

    1981-08-01

    The purpose of this document is to examine the use of plain skull films in the management of head trauma. This report reviews and examines such issues as utilization, the use of referral criteria, efficacy, economic and social considerations, and radiation risk. Appendices include detailed information on the utility of skull radiography, studies dealing with the development of high-yield criteria for ordering skull x-rays, and the analysis of potential radiation risk to the U.S. population. (KRM)

  2. Contributions to the functional morphology of caudate skulls: kinetic and akinetic forms

    PubMed Central

    Handschuh, Stephan; Lukanov, Simeon; Naumov, Borislav

    2016-01-01

    A strongly ossified and rigid skull roof, which prevents parietal kinesis, has been reported for the adults of all amphibian clades. Our μ-CT investigations revealed that the Buresch’s newt (Triturus ivanbureschi) possess a peculiar cranial construction. In addition to the typical amphibian pleurokinetic articulation between skull roof and palatoquadrate associated structures, we found flexible connections between nasals and frontals (prokinesis), vomer and parasphenoid (palatokinesis), and between frontals and parietals (mesokinesis). This is the first description of mesokinesis in urodelans. The construction of the skull in the Buresch’s newts also indicates the presence of an articulation between parietals and the exocipitals, discussed as a possible kind of metakinesis. The specific combination of pleuro-, pro-, meso-, palato-, and metakinetic skull articulations indicate to a new kind of kinetic systems unknown for urodelans to this date. We discuss the possible neotenic origin of the skull kinesis and pose the hypothesis that the kinesis in T. ivanbureschi increases the efficiency of fast jaw closure. For that, we compared the construction of the skull in T. ivanbureschi to the akinetic skull of the Common fire salamander Salamandra salamandra. We hypothesize that the design of the skull in the purely terrestrial living salamander shows a similar degree of intracranial mobility. However, this mobility is permitted by elasticity of some bones and not by true articulation between them. We comment on the possible relation between the skull construction and the form of prey shaking mechanism that the species apply to immobilize their victims. PMID:27688958

  3. A rapid and reversible skull optical clearing method for monitoring cortical blood flow

    NASA Astrophysics Data System (ADS)

    Zhang, Chao; Zhao, Yanjie; Shi, Rui; Zhu, Dan

    2016-03-01

    In vivo cortex optical imaging is of great important for revealing both structural and functional architecture of brain with high temporal-spatial resolution. To reduce the limitation of turbid skull, researchers had to establish various skull windows or directly expose cortex through craniotomy. Here we developed a skull optical clearing method to make skull transparent. Laser speckle contrast imaging technique was used to monitor the cortical blood flow after topical treatment with the optical clearing agents. The results indicated that the image contrast increased gradually, and then maintained at a high level after 15 min for adult mice, which made the image quality and resolution of micro-vessels nearly approximate to those of exposed cortex. Both the cortical blood flow velocity almost kept constant after skull became transparent. Besides, the treatment of physiological saline on the skull could make skull return to the initial state again and the skull could become transparent again when SOCS retreated it. Thus, we could conclude that the skull optical clearing method was rapid, valid, reversible and safe, which provided us available approach for performing the cortical structural and functional imaging at high temporal-spatial resolution.

  4. The Skull Base in the Evaluation of Sinonasal Disease: Role of Computed Tomography and MR Imaging.

    PubMed

    Connor, Steve E J

    2015-11-01

    The median anterior and central skull base forms an interface between the sinonasal and intracranial compartments. Due to the proximity of the intracranial structures, skull base involvement is a key assessment when evaluating the spread of sinonasal disease. This review describes the pertinent anatomy and the role of computed tomography and MR imaging in evaluating the median anterior and central skull base. The imaging appearances of pathologic processes that involve and traverse the skull base between the sinonasal and intracranial compartments are discussed and illustrated.

  5. Contributions to the functional morphology of caudate skulls: kinetic and akinetic forms.

    PubMed

    Natchev, Nikolay; Handschuh, Stephan; Lukanov, Simeon; Tzankov, Nikolay; Naumov, Borislav; Werneburg, Ingmar

    2016-01-01

    A strongly ossified and rigid skull roof, which prevents parietal kinesis, has been reported for the adults of all amphibian clades. Our μ-CT investigations revealed that the Buresch's newt (Triturus ivanbureschi) possess a peculiar cranial construction. In addition to the typical amphibian pleurokinetic articulation between skull roof and palatoquadrate associated structures, we found flexible connections between nasals and frontals (prokinesis), vomer and parasphenoid (palatokinesis), and between frontals and parietals (mesokinesis). This is the first description of mesokinesis in urodelans. The construction of the skull in the Buresch's newts also indicates the presence of an articulation between parietals and the exocipitals, discussed as a possible kind of metakinesis. The specific combination of pleuro-, pro-, meso-, palato-, and metakinetic skull articulations indicate to a new kind of kinetic systems unknown for urodelans to this date. We discuss the possible neotenic origin of the skull kinesis and pose the hypothesis that the kinesis in T. ivanbureschi increases the efficiency of fast jaw closure. For that, we compared the construction of the skull in T. ivanbureschi to the akinetic skull of the Common fire salamander Salamandra salamandra. We hypothesize that the design of the skull in the purely terrestrial living salamander shows a similar degree of intracranial mobility. However, this mobility is permitted by elasticity of some bones and not by true articulation between them. We comment on the possible relation between the skull construction and the form of prey shaking mechanism that the species apply to immobilize their victims.

  6. Contributions to the functional morphology of caudate skulls: kinetic and akinetic forms.

    PubMed

    Natchev, Nikolay; Handschuh, Stephan; Lukanov, Simeon; Tzankov, Nikolay; Naumov, Borislav; Werneburg, Ingmar

    2016-01-01

    A strongly ossified and rigid skull roof, which prevents parietal kinesis, has been reported for the adults of all amphibian clades. Our μ-CT investigations revealed that the Buresch's newt (Triturus ivanbureschi) possess a peculiar cranial construction. In addition to the typical amphibian pleurokinetic articulation between skull roof and palatoquadrate associated structures, we found flexible connections between nasals and frontals (prokinesis), vomer and parasphenoid (palatokinesis), and between frontals and parietals (mesokinesis). This is the first description of mesokinesis in urodelans. The construction of the skull in the Buresch's newts also indicates the presence of an articulation between parietals and the exocipitals, discussed as a possible kind of metakinesis. The specific combination of pleuro-, pro-, meso-, palato-, and metakinetic skull articulations indicate to a new kind of kinetic systems unknown for urodelans to this date. We discuss the possible neotenic origin of the skull kinesis and pose the hypothesis that the kinesis in T. ivanbureschi increases the efficiency of fast jaw closure. For that, we compared the construction of the skull in T. ivanbureschi to the akinetic skull of the Common fire salamander Salamandra salamandra. We hypothesize that the design of the skull in the purely terrestrial living salamander shows a similar degree of intracranial mobility. However, this mobility is permitted by elasticity of some bones and not by true articulation between them. We comment on the possible relation between the skull construction and the form of prey shaking mechanism that the species apply to immobilize their victims. PMID:27688958

  7. Contributions to the functional morphology of caudate skulls: kinetic and akinetic forms

    PubMed Central

    Handschuh, Stephan; Lukanov, Simeon; Naumov, Borislav

    2016-01-01

    A strongly ossified and rigid skull roof, which prevents parietal kinesis, has been reported for the adults of all amphibian clades. Our μ-CT investigations revealed that the Buresch’s newt (Triturus ivanbureschi) possess a peculiar cranial construction. In addition to the typical amphibian pleurokinetic articulation between skull roof and palatoquadrate associated structures, we found flexible connections between nasals and frontals (prokinesis), vomer and parasphenoid (palatokinesis), and between frontals and parietals (mesokinesis). This is the first description of mesokinesis in urodelans. The construction of the skull in the Buresch’s newts also indicates the presence of an articulation between parietals and the exocipitals, discussed as a possible kind of metakinesis. The specific combination of pleuro-, pro-, meso-, palato-, and metakinetic skull articulations indicate to a new kind of kinetic systems unknown for urodelans to this date. We discuss the possible neotenic origin of the skull kinesis and pose the hypothesis that the kinesis in T. ivanbureschi increases the efficiency of fast jaw closure. For that, we compared the construction of the skull in T. ivanbureschi to the akinetic skull of the Common fire salamander Salamandra salamandra. We hypothesize that the design of the skull in the purely terrestrial living salamander shows a similar degree of intracranial mobility. However, this mobility is permitted by elasticity of some bones and not by true articulation between them. We comment on the possible relation between the skull construction and the form of prey shaking mechanism that the species apply to immobilize their victims.

  8. Fourier analysis of the forehead shape of skull and sex determination by use of computer.

    PubMed

    Inoue, M

    1990-09-01

    The forehead shape of the skull was quantified with the Fourier analysis method by using 100 male and 100 female radiographic lateral views of the skull, and sex difference in the forehead shape was studied. Furthermore to predict the sex of cranial specimens, an automated sexing computer system based on the quantification was created. The effectiveness of the system was evaluated by checking 56 male and 56 female specimens of skulls. This system was proved to discriminate male and female skulls from forehead shapes with 85% accuracy.

  9. A diagnostic dilemma of central skull base osteomyelitis mimicking neoplasia in a diabetic patient

    PubMed Central

    Ganhewa, Aparna Dasunmalee; Kuthubutheen, Jafri

    2013-01-01

    We present a case which illustrates the diagnostic difficulty in distinguishing between osteomyelitis of the central skull base and base of skull tumours. A woman in her early forties presented with seizures and multiple cranial nerve palsies. She also had a background of chronic otalgia and poorly controlled diabetes mellitus. The clinical diagnosis of skull base osteomyelitis (SBO) was made, but both MRI and bone scans were unable to distinguish this from a skull base malignancy on imaging criteria. Eventually biopsies were required to exclude the diagnosis of malignancy and the patient was treated for central SBO. PMID:23355560

  10. Deficiency of zebrafish fgf20a results in aberrant skull remodeling that mimics both human cranial disease and evolutionarily important fish skull morphologies.

    PubMed

    Cooper, W James; Wirgau, Rachel M; Sweet, Elly M; Albertson, R Craig

    2013-01-01

    The processes that direct skull remodeling are of interest to both human-oriented studies of cranial dysplasia and evolutionary studies of skull divergence. There is increasing awareness that these two fields can be mutually informative when natural variation mimics pathology. Here we describe a zebrafish mutant line, devoid of blastema (dob), which does not have a functional fgf20a protein, and which also presents cranial defects similar to both adaptive and clinical variation. We used geometric morphometric methods to provide quantitative descriptions of the effects of the dob mutation on skull morphogenesis. In combination with "whole-mount in situ hybridization" labeling of normal fgf20a expression and assays for osteoblast and osteoclast activity, the results of these analyses indicate that cranial dysmorphologies in dob zebrafish are generated by aberrations in post-embryonic skull remodeling via decreased osteoblasotgenesis and increased osteoclastogenesis. Mutational effects include altered skull vault geometries and midfacial hypoplasia that are consistent with key diagnostic signs for multiple human craniofacial syndromes. These phenotypic shifts also mimic changes in the functional morphology of fish skulls that have arisen repeatedly in several highly successful radiations (e.g., damselfishes and East-African rift-lake cichlids). Our results offer the dob/fgf20a mutant as an experimentally tractable model with which to examine post-embryonic skull development as it relates to human disease and vertebrate evolution.

  11. Deficiency of zebrafish fgf20a results in aberrant skull remodeling that mimics both human cranial disease and evolutionarily important fish skull morphologies

    PubMed Central

    Cooper, W. James; Wirgau, Rachel M.; Sweet, Elly M.; Albertson, R. Craig

    2013-01-01

    The processes that direct skull remodeling are of interest to both human-oriented studies of cranial dysplasia and evolutionary studies of skull divergence. There is increasing awareness that these two fields can be mutually informative when natural variation mimics pathology. Here we describe a zebrafish mutant line, devoid of blastema(dob), which does not have a functional fgf20a protein, and which also presents cranial defects similar to both adaptive and clinical variation. We used geometric morphometric methods to provide quantitative descriptions of the effects of the dob mutation on skull morphogenesis. In combination with whole-mount in situ hybridization labeling of normal fgf20a expression and assays for osteoblast and osteoclast activity, the results of these analyses indicate that cranial dysmorphologies in dob zebrafish are generated by aberrations in post-embryonic skull remodeling via decreased osteoblasotgenesis and increased osteoclastogenesis. Mutational effects include altered skull vault geometries and midfacial hypoplasia that are consistent with key diagnostic signs for multiple human craniofacial syndromes. These phenotypic shifts also mimic changes in the functional morphology of fish skulls that have arisen repeatedly in several highly successful radiations (e.g., damselfishes and East-African rift-lake cichlids). Our results offer the dob/fgf20a mutant as an experimentally tractable model with which to examine post-embryonic skull development as it relates to human disease and evolution. PMID:24261444

  12. Catecholamine-Secreting Paragangliomas at the Skull Base

    PubMed Central

    Kuhweide, Rudolf; Lanser, Michael J.; Fisch, Ugo

    1996-01-01

    Paragangliomas (glomus tumors) comprise 15% of all neoplasms at the skull base. Despite extensive growth, these tumors usually do not secrete active biogenic substances into the circulation in sufficient quantities to produce symptoms. When they do secrete large amounts of catecholamines, they will cause symptoms that mimic a pheochromocytoma. The still confusing nomenclature of paragangliomas is reviewed, and the clinical work-up, surgical treatment, and follow-up of five patients with catecholamine-secreting paragangliomas of temporal bone (3), infratemporal fossa (1), and nasopharynx (1) are presented and discussed. ImagesFigure 3Figure 3Figure 4Figure 5 PMID:17170951

  13. The complete skull and skeleton of an early dinosaur.

    PubMed

    Sereno, P C; Novas, F E

    1992-11-13

    The unearthing of a complete skull and skeleton of the early dinosaur Herrerasaurus ischigualastensis sheds light on the early evolution of dinosaurs. Discovered in the Upper Triassic Ischigualasto Formation of Argentina, the fossils show that Herrerasaurus, a primitive theropod, was an agile, bipedal predator with a short forelimb specialized for grasping and raking. The fossils clarify anatomical features of the common ancestor of all dinosaurs. Herrerasaurus and younger dinosaurs from Upper Triassic beds in Argentina suggest that the dinosaurian radiation was well under way before dinosaurs dominated terrestrial vertebrate communities in taxonomic diversity and abundance.

  14. Craniofacial levels and the morphological maturation of the human skull

    PubMed Central

    Bastir, Markus; Rosas, Antonio; O’Higgins, Paul

    2006-01-01

    It is well known that the human skull achieves adult size through a superior–inferior gradient of maturation. Because the basicranium matures in size before the face, it has been suggested that the form of the basicranium might have ontogenetic knock-on effects on that of the face. However, although sequential spatially organized maturation of size is well described in the cranium, the maturation of skull shape is not. Knowledge of the maturation of shape is important, nevertheless, because it is claimed that the early determination of the spatial configuration of basicranial components, where the facial skeleton attaches, is relevant in the spatio-temporal ontogenetic cascade from basicranium to face. This paper examines the ontogeny of various components of the human skull in 28 individuals from the longitudinal Denver Growth Study. Sixty-six landmarks and semilandmarks were digitized on 228 X-rays and analysed using geometric morphometric methods. Bootstrapped confidence intervals for centroid size support previous studies suggesting a supero-inferior gradient of growth maturation (size over time), while developmental maturation (shape over time) is more complex. A sequence of shape maturation is described, in which the earliest structure to mature in shape was the midline cranial base (7–8 years), followed by the lateral cranial floor (11–12), midline neurocranium (9–10) and facial and mandibular structures (15–16). The absolute ages of shape maturation of the latter three depended on the criterion of maturity used, which was not the case for the basicranial components. Additionally, ontogenetic dissociations were found between the maturation of size and shape of the midline cranial base and lateral floor, possibly underlining its role as structural ‘interface’ between brain and facial ontogeny. These findings imply potential for bidirectional developmental influences between the lateral cranial floor and the face until about 11–12 years. The

  15. Telangiectatic osteosarcoma of the skull. A post-Paget case.

    PubMed

    Donato, G; Lavano, A; Volpentesta, G; Chirchiglia, D; Veraldi, A; De Rose, F; Iannello, A N; Stroscio, C; Signorelli, C D

    1997-01-01

    We report a case of post-Paget telangiectatic osteosarcoma of the skull in a 75-year-old woman. Such a neoplasia is a rare variant of osteosarcoma, a tumor rare in the cranic bones. The patient was submitted for a careful analysis by the following procedures: technetium scintigram, X-rays, CT scan, and MRI. After the surgical procedure, pathological examination confirmed the diagnosis. Both radiological and pathological pattern of this tumor are discussed in relation to the differential diagnosis. Our report shows that benign lesions may represent a possible cause of diagnostic errors. They must be excluded by histological analysis.

  16. [Paleopathology of deafness: skulls of the Dupuytren Museum].

    PubMed

    Benmoussa, Nadia; Muller, A -L; Kerner, J; Josset, P; Conan, P; Charlier, P

    2015-01-01

    In the 18th and 19th centuries, the Dupuytren Museum was indispensable for the knowledge of pathological anatomy for physicians and surgeons. Nowadays, it is more a museum than a learning unit, but it provides an opportunity to understand through numerous scientific studies the origin of diseases, injuries mechanism and the functional consequences of which could suffer some patients. This study illustrates the interest of the study on pieces in pathological anatomy's museums, this time across selected skulls which belonged to hearing loss people. bizarre.

  17. Olfaction in Endoscopic Sinus and Skull Base Surgery.

    PubMed

    Thompson, Christopher F; Kern, Robert C; Conley, David B

    2015-10-01

    Olfactory dysfunction is a common complaint for patients with chronic rhinosinusitis, because smell loss decreases a patient's quality of life. Smell loss is caused by obstruction from polyps, nasal discharge, and mucosal edema, as well as inflammatory changes within the olfactory epithelium. Addressing olfaction before endoscopic sinus and skull base surgery is important in order to set postoperative expectations, because an improvement in smell is difficult to predict. Several commercially available olfactory testing measures are available and can easily be administered in clinic. During surgery, careful dissection within the olfactory cleft is recommended in order to optimize postoperative olfactory function.

  18. Surfactant-driven fracture of gels: Growth

    NASA Astrophysics Data System (ADS)

    Daniels, Karen; Schillaci, Mark; Bostwick, Joshua

    2012-11-01

    A droplet of surfactant spreading on a gel substrate can produce fractures on the gel surface, which originate at the contact-line and propagate outwards in a star-burst pattern. Fractures have previously been observed to initiate through a thermal process, with the number of fractures controlled by the ratio of surface tension differential to gel shear modulus. After the onset of fracture, experiments show the arm length grows with universal power law L =t 3 / 4 that does not scale with any material parameters (Daniels et al. 2007, PRL), including super-spreading surfactants (Spandangos et al. 2012, Langmuir). We develop a model for crack growth controlled by the transport of an inviscid fluid into the fracture tip. While treating the gel as a linear material correctly predicts power-law growth, we find that only by considering a Neo-Hookean (incompressible) material do we obtain agreement with the experiments.

  19. Percolation Theory and Modern Hydraulic Fracturing

    NASA Astrophysics Data System (ADS)

    Norris, J. Q.; Turcotte, D. L.; Rundle, J. B.

    2015-12-01

    During the past few years, we have been developing a percolation model for fracking. This model provides a powerful tool for understanding the growth and properties of the complex fracture networks generated during a modern high volume hydraulic fracture stimulations of tight shale reservoirs. The model can also be used to understand the interaction between the growing fracture network and natural reservoir features such as joint sets and faults. Additionally, the model produces a power-law distribution of bursts which can easily be compared to observed microseismicity.

  20. Relevance of Whitnall's tubercle and auditory meatus in diagnosing exclusions during skull-photo superimposition.

    PubMed

    Jayaprakash, Paul T; Hashim, Natassha; Yusop, Ridzuan Abd Aziz Mohd

    2015-08-01

    Video vision mixer based skull-photo superimposition is a popular method for identifying skulls retrieved from unidentified human remains. A report on the reliability of the superimposition method suggested increased failure rates of 17.3 to 32% to exclude and 15 to 20% to include skulls while using related and unrelated face photographs. Such raise in failures prompted an analysis of the methods employed for the research. The protocols adopted for assessing the reliability are seen to vary from those suggested by the practitioners in the field. The former include overlaying the skull- and face-images on the basis of morphology by relying on anthropometric landmarks on the front plane of the face-images and evaluating the goodness of match depending on mix-mode images; the latter consist of orienting the skull considering landmarks on both the eye and ear planes of the face- and skull-images and evaluating the match utilizing images seen in wipe-mode in addition to those in mix-mode. Superimposition of a skull with face-images of five living individuals in two sets of experiments, one following the procedure described for the research on reliability and the other applying the methods suggested by the practitioners has shown that overlaying the images on the basis of morphology depending on the landmarks on the front plane alone and assessing the match in mix-mode fails to exclude the skull. However, orienting the skull relying on the relationship between the anatomical landmarks on the skull- and face-images such as Whitnall's tubercle and exocanthus in the front (eye) plane and the porion and tragus in the rear (ear) plane as well as assessing the match using wipe-mode images enables excluding that skull while superimposing with the same set of face-images.

  1. Does skull morphology constrain bone ornamentation? A morphometric analysis in the Crocodylia.

    PubMed

    Clarac, F; Souter, T; Cubo, J; de Buffrénil, V; Brochu, C; Cornette, R

    2016-08-01

    Previous quantitative assessments of the crocodylians' dermal bone ornamentation (this ornamentation consists of pits and ridges) has shown that bone sculpture results in a gain in area that differs between anatomical regions: it tends to be higher on the skull table than on the snout. Therefore, a comparative phylogenetic analysis within 17 adult crocodylian specimens representative of the morphological diversity of the 24 extant species has been performed, in order to test if the gain in area due to ornamentation depends on the skull morphology, i.e. shape and size. Quantitative assessment of skull size and shape through geometric morphometrics, and of skull ornamentation through surface analyses, produced a dataset that was analyzed using phylogenetic least-squares regression. The analyses reveal that none of the variables that quantify ornamentation, be they on the snout or the skull table, is correlated with the size of the specimens. Conversely, there is more disparity in the relationships between skull conformations (longirostrine vs. brevirostrine) and ornamentation. Indeed, both parameters GApit (i.e. pit depth and shape) and OArelat (i.e. relative area of the pit set) are negatively correlated with snout elongation, whereas none of the values quantifying ornamentation on the skull table is correlated with skull conformation. It can be concluded that bone sculpture on the snout is influenced by different developmental constrains than on the skull table and is sensible to differences in the local growth 'context' (allometric processes) prevailing in distinct skull parts. Whatever the functional role of bone ornamentation on the skull, if any, it seems to be restricted to some anatomical regions at least for the longirostrine forms that tend to lose ornamentation on the snout.

  2. Does skull morphology constrain bone ornamentation? A morphometric analysis in the Crocodylia.

    PubMed

    Clarac, F; Souter, T; Cubo, J; de Buffrénil, V; Brochu, C; Cornette, R

    2016-08-01

    Previous quantitative assessments of the crocodylians' dermal bone ornamentation (this ornamentation consists of pits and ridges) has shown that bone sculpture results in a gain in area that differs between anatomical regions: it tends to be higher on the skull table than on the snout. Therefore, a comparative phylogenetic analysis within 17 adult crocodylian specimens representative of the morphological diversity of the 24 extant species has been performed, in order to test if the gain in area due to ornamentation depends on the skull morphology, i.e. shape and size. Quantitative assessment of skull size and shape through geometric morphometrics, and of skull ornamentation through surface analyses, produced a dataset that was analyzed using phylogenetic least-squares regression. The analyses reveal that none of the variables that quantify ornamentation, be they on the snout or the skull table, is correlated with the size of the specimens. Conversely, there is more disparity in the relationships between skull conformations (longirostrine vs. brevirostrine) and ornamentation. Indeed, both parameters GApit (i.e. pit depth and shape) and OArelat (i.e. relative area of the pit set) are negatively correlated with snout elongation, whereas none of the values quantifying ornamentation on the skull table is correlated with skull conformation. It can be concluded that bone sculpture on the snout is influenced by different developmental constrains than on the skull table and is sensible to differences in the local growth 'context' (allometric processes) prevailing in distinct skull parts. Whatever the functional role of bone ornamentation on the skull, if any, it seems to be restricted to some anatomical regions at least for the longirostrine forms that tend to lose ornamentation on the snout. PMID:27061077

  3. Minimizing the Fluid Used to Induce Fracturing

    NASA Astrophysics Data System (ADS)

    Boyle, E. J.

    2015-12-01

    The less fluid injected to induce fracturing means less fluid needing to be produced before gas is produced. One method is to inject as fast as possible until the desired fracture length is obtained. Presented is an alternative injection strategy derived by applying optimal system control theory to the macroscopic mass balance. The picture is that the fracture is constant in aperture, fluid is injected at a controlled rate at the near end, and the fracture unzips at the far end until the desired length is obtained. The velocity of the fluid is governed by Darcy's law with larger permeability for flow along the fracture length. Fracture growth is monitored through micro-seismicity. Since the fluid is assumed to be incompressible, the rate at which fluid is injected is balanced by rate of fracture growth and rate of loss to bounding rock. Minimizing injected fluid loss to the bounding rock is the same as minimizing total injected fluid How to change the injection rate so as to minimize the total injected fluid is a problem in optimal control. For a given total length, the variation of the injected rate is determined by variations in overall time needed to obtain the desired fracture length, the length at any time, and the rate at which the fracture is growing at that time. Optimal control theory leads to a boundary condition and an ordinary differential equation in time whose solution is an injection protocol that minimizes the fluid used under the stated assumptions. That method is to monitor the rate at which the square of the fracture length is growing and adjust the injection rate proportionately.

  4. Radial head fracture - aftercare

    MedlinePlus

    Elbow fracture - radial head - aftercare ... to 2 weeks. If you have a small fracture and your bones did not move around much, ... to see a bone doctor (orthopedic surgeon). Some fractures require surgery to: Insert pins and plates to ...

  5. HelixFlex: bioinspired maneuverable instrument for skull base surgery.

    PubMed

    Gerboni, Giada; Henselmans, Paul W J; Arkenbout, Ewout A; van Furth, Wouter R; Breedveld, Paul

    2015-12-01

    Endoscopic endonasal surgery is currently regarded as the 'gold standard' for operating on pituitary gland tumors, and is becoming more and more accepted for treatment of other skull base lesions. However, endoscopic surgical treatment of most skull base pathologies, including certain pituitary tumors, is severely impaired by current instruments lack of maneuverability. Especially, gaining access to, and visibility of, difficult-to-reach anatomical corners without interference with surrounding neurovascular structures or other instruments, is a challenge. In this context there is the need for instruments that are able to provide a stable shaft position, while both the orientation and the position of the end-effector can be independently controlled. Current instruments that allow for this level of maneuverability are usually mechanically complex, and hence less suitable for mass production. This study therefore focuses on the development of a new actuation technique that allows for the required maneuverability while reducing the construction complexity. This actuation technique, referred to as multi-actuation, integrates multiple cable routings into a single steerable structure. Multi-actuation has been successfully integrated and tested in a handheld prototype instrument called HelixFlex. HelixFlex contains a 4 degrees of freedom maneuverable 5.8 mm (diameter) tip and shows promising results concerning its maneuverability and potential rigidity.

  6. Hard palate and retropalatal space in adult Japanese dry skulls.

    PubMed

    Mahmud, S

    1989-08-01

    This is a basic study designed to elucidate the correlation between the lengths of the hard palate and retropalatal space. We also measured the mean lengths of the hard palate and the retropalatal space, emphasizing on measuring the mean proportional lengths of the hard palate and retropalatal space in relation to the total lengths of these two. This osteometric study was done on 89 adult Japanese dry skulls involving, the measurement of five linear dimensions including two modified dimensions. The lengths of the hard palate had a statistically significant correlation with the retropalatal space length. Clinical significance of this study is that, it will be advantageous for the better assessment of the bony anatomy of palatal inadequacy patients, with speech problems, resulting from abnormalities in the palate and the velopharyngeal port. This study also reports a new term "RETROPALATAL SPACE" to represent the gap in the base of dry skulls between the posterior border of the hard palate and the anterior margin of the for-a men magnum.

  7. A skull stripping method using deformable surface and tissue classification

    NASA Astrophysics Data System (ADS)

    Tao, Xiaodong; Chang, Ming-Ching

    2010-03-01

    Many neuroimaging applications require an initial step of skull stripping to extract the cerebrum, cerebellum, and brain stem. We approach this problem by combining deformable surface models and a fuzzy tissue classification technique. Our assumption is that contrast exists between brain tissue (gray matter and white matter) and cerebrospinal fluid, which separates the brain from the extra-cranial tissue. We first analyze the intensity of the entire image to find an approximate centroid of the brain and initialize an ellipsoidal surface around it. We then perform a fuzzy tissue classification with bias field correction within the surface. Tissue classification and bias field are extrapolated to the entire image. The surface iteratively deforms under a force field computed from the tissue classification and the surface smoothness. Because of the bias field correction and tissue classification, the proposed algorithm depends less on particular imaging contrast and is robust to inhomogeneous intensity often observed in magnetic resonance images. We tested the algorithm on all T1 weighted images in the OASIS database, which includes skull stripping results using Brain Extraction Tool; the Dice scores have an average of 0.948 with a standard deviation of 0.017, indicating a high degree of agreement. The algorithm takes on average 2 minutes to run on a typical PC and produces a brain mask and membership functions for gray matter, white matter, and cerebrospinal fluid. We also tested the algorithm on T2 images to demonstrate its generality, where the same algorithm without parameter adjustment gives satisfactory results.

  8. A Case of Skull Base Osteomyelitis with Multiple Cerebral Infarction

    PubMed Central

    Miyabe, Haruka; Nakajima, Takahiro; Morizane, Natsue; Enomoto, Keisuke; Hirose, Masayuki; Hazama, Toshinori

    2016-01-01

    Skull base osteomyelitis is classically documented as an extension of malignant otitis externa. Initial presentation commonly includes aural symptoms and cranial nerve dysfunctions. Here we present a case that emerged with multiple infarctions in the right cerebrum. A male in his 70s with diabetes mellitus and chronic renal failure presented with left hemiparesis. Imaging studies showed that blood flow in the carotid artery remained at the day of onset but was totally occluded 7 days later. However, collateral blood supply prevented severe infarction. These findings suggest that artery-to-artery embolization from the petrous and/or cavernous portion of the carotid artery caused the multiple infarctions observed on initial presentation. Osteomyelitis of the central skull base was diagnosed on the basis of the following findings taken together: laboratory results showing high levels of inflammation, presence of Pseudomonas aeruginosa in the otorrhea and blood culture, multiple cranial nerve palsies that appeared later, the bony erosion observed on CT, and the mass lesion on MRI. Osteomyelitis was treated successfully by long-term antibiotic therapy; however, the patient experienced cefepime-induced neurotoxicity during therapy. The potential involvement of the internal carotid artery in this rare and life-threatening disease is of particular interest in this case. PMID:27597916

  9. Plasmacytoma of the Skull Base: A Meta-Analysis.

    PubMed

    Na'ara, Shorook; Amit, Moran; Gil, Ziv; Billan, Salem

    2016-02-01

    Objective Extramedullary plasmacytomas are rare tumors. In the current study we aim to characterize its clinical course at the skull base and define the most appropriate therapeutic protocol. Methods We conducted a meta-analysis of articles in the English language that included data on the treatment and outcome of plasmacytoma of the base of skull. Results The study cohort consisted of 47 patients. The tumor originated from the clivus and sphenoclival region in 28 patients (59.5%), the nasopharynx in 10 patients (21.2%), the petrous apex in 5 patients (10.6%), and the orbital roof in 4 patients (8.5%). The chief complaints at presentation included recurrent epistaxis and cranial nerve palsy, according to the site of tumor. Twenty-two patients (46.8%) had surgical treatment; 25 (53.2%) received radiation therapy. Adjuvant therapy was administered in 11 cases (50%) with concurrent multiple myeloma. The 2-year and 5-year overall survival rates were 78% and 59%, respectively. Clear margin resection was achieved in a similar proportion of patients who underwent endoscopic surgery and open surgery (p = 0.83). A multivariate analysis of outcome showed a similar survival rate of patients treated surgically or with radiotherapy. Conclusions The mainstay of treatment for plasmacytoma is based on radiation therapy, but when total resection is feasible, endoscopic resection is a valid option. PMID:26949590

  10. High rate properties of porcine skull bone tissue

    NASA Astrophysics Data System (ADS)

    Herwig, Kyle Jeffry

    Several recent studies have shown the importance of understanding the nature of blast injuries. Traditionally, the lungs and other air filled organs were the focus of these injuries but it is being discovered that some level of brain trauma may result after encountering a blast. These injuries are referred to as traumatic brain injuries, or TBI. There has been many clinical studies and statistical analyses done concerning these injuries, but there is still no physical understanding of the problem. In order to develop a model of how this injury can occur, rate dependent material properties of the tissues the stress wave will travel through are needed. In this study, the compressive response of porcine skull bone through the thickness direction was experimentally determined over a wide range of rates, ranging from 0.001 sec -1 to approximately 3000 sec-1. The results reveal that for most mechanical properties there is a clear rate dependence of the material. However, only one subset of the skull section appeared to have a rate dependent initial modulus, with the rest showing no significant statistical dependence on loading rate. Other mechanical properties appeared to be affected by the loading rate, including the strain energy density.

  11. Intraoperative monitoring of motor cranial nerves in skull base surgery.

    PubMed

    Maurer, J; Pelster, H; Amedee, R G; Mann, W J

    1995-01-01

    Intraoperative monitoring of cranial nerves is performed to minimize postoperative cranial nerve dysfunction. We performed electrophysiologic monitoring of motor cranial nerves with a NIM 2 unit from Xomed Treace and a patient multiplexer developed in our clinic. This multiplexer allows simultaneous monitoring of four cranial nerves and is additionally equipped with a bipolar stimulation mode. This intraoperative monitoring was used during 102 skull base operations. Of these, 44 operations were acoustic neuroma removals by translabyrinthine approach and 36 by a middle fossa approach. Various operations, including removal of tumors of the jugular foramen and the infratemporal fossa, were performed in the remaining 22 patients. The facial nerve, being the most frequently monitored nerve, was evaluated both preoperatively and intraoperatively. Electrophysiologic data were evaluated with respect to their predictive value for postoperative facial nerve function. The relative percent decrease in amplitude of the electromyogram after resection compared to that observed before resection seems to be of some predictive value for the postoperative facial nerve function. A 50 to 60% decrease or more is associated with an increase in the House classification. Intraoperative monitoring is a useful tool in skull base surgery, allowing for safer and faster identification of motor nerves in pathologic-anatomic conditions. It allows the surgeon a degree of comfort by providing immediate information regarding the status of the nerve. It may also improve postoperative nerve function and shorten operating time. Additionally, neuromonitoring provides some information about expected postoperative facial nerve function.

  12. Skull growth of the Korean water deer, Hydropotes inermis argyropus.

    PubMed

    Kim, Yungkun; Suzuki, Satoshi; Na, Ki-Jeong; Lee, Hang; Kimura, Junpei

    2013-07-31

    Craniomandibular traits of the water deer from the Korean peninsula were examined to assess size change in growth between age groups and sexes. Univariate and multivariate analyses were conducted based on 34 cranial and 11 mandibular measurements from both sexes. Statistical comparisons of skull measurements revealed a significantly different growth pattern between the sexes. For the male, the size change of the cranium and mandible was straight through age groups, constantly. On the other hand, the size of the cranium and mandible of the female was changed relatively steeper than that of the male in age groups 2 to 3, and the growth curves from age group 3 to 4 were more gradual than age groups 2 to 3. Principal component analysis showed that these 2 sexes have a similar trend. In the allometry analysis, there were differences in growth in 5 traits in both sexes. In conclusion, our study suggests that the male and the female Korean water deer had a similar trend for their growth, although there was a small difference of skull growth for age groups.

  13. A Case of Skull Base Osteomyelitis with Multiple Cerebral Infarction

    PubMed Central

    Miyabe, Haruka; Nakajima, Takahiro; Morizane, Natsue; Enomoto, Keisuke; Hirose, Masayuki; Hazama, Toshinori

    2016-01-01

    Skull base osteomyelitis is classically documented as an extension of malignant otitis externa. Initial presentation commonly includes aural symptoms and cranial nerve dysfunctions. Here we present a case that emerged with multiple infarctions in the right cerebrum. A male in his 70s with diabetes mellitus and chronic renal failure presented with left hemiparesis. Imaging studies showed that blood flow in the carotid artery remained at the day of onset but was totally occluded 7 days later. However, collateral blood supply prevented severe infarction. These findings suggest that artery-to-artery embolization from the petrous and/or cavernous portion of the carotid artery caused the multiple infarctions observed on initial presentation. Osteomyelitis of the central skull base was diagnosed on the basis of the following findings taken together: laboratory results showing high levels of inflammation, presence of Pseudomonas aeruginosa in the otorrhea and blood culture, multiple cranial nerve palsies that appeared later, the bony erosion observed on CT, and the mass lesion on MRI. Osteomyelitis was treated successfully by long-term antibiotic therapy; however, the patient experienced cefepime-induced neurotoxicity during therapy. The potential involvement of the internal carotid artery in this rare and life-threatening disease is of particular interest in this case.

  14. Skull-Stripping with Machine Learning Deformable Organisms

    PubMed Central

    Prasad, Gautam; Joshi, Anand A.; Feng, Albert; Toga, Arthur W.; Thompson, Paul M.; Terzopoulos, Demetri

    2014-01-01

    Background Segmentation methods for medical images may not generalize well to new data sets or new tasks, hampering their utility. We attempt to remedy these issues using deformable organisms to create an easily customizable segmentation plan. We validate our framework by creating a plan to locate the brain in 3D magnetic resonance images of the head (skull-stripping). New Method Our method borrows ideas from artificial life to govern a set of deformable models. We use control processes such as sensing, proactive planning, reactive behavior, and knowledge representation to segment an image. The image may have landmarks and features specific to that dataset; these may be easily incorporated into the plan. In addition, we use a machine learning method to make our segmentation more accurate. Results Our method had the least Hausdorff distance error, but included slightly less brain voxels (false negatives). It also had the lowest false positive error and performed on par to skull-stripping specific method on other metrics. Comparison with Existing Method(s) We tested our method on 838 T1-weighted images, evaluating results using distance and overlap error metrics based on expert gold standard segmentations. We evaluated the results before and after the learning step to quantify its benefit; we also compare our results to three other widely used methods: BSE, BET, and the Hybrid Watershed algorithm. Conclusions Our framework captures diverse categories of information needed for brain segmentation and will provide a foundation for tackling a wealth of segmentation problems. PMID:25124851

  15. Novel techniques and the future of skull base reconstruction.

    PubMed

    Meier, Joshua C; Bleier, Benjamin S

    2013-01-01

    The field of endoscopic skull base surgery has evolved considerably in recent years fueled largely by advances in both imaging and instrumentation. While the indications for these approaches continue to be extended, the ability to reconstruct the resultant defects has emerged as a rate-limiting obstacle. Postoperative failures with current multilayer grafting techniques remain significant and may increase as the indications for endoscopic resections continue to expand. Laser tissue welding represents a novel method of wound repair in which laser energy is applied to a chromophore doped biologic solder at the wound edge to create a laser weld (fig. 1). These repairs are capable of withstanding forces far exceeding those exerted by intracranial pressure with negligible collateral thermal tissue injury. Recent clinical trials have demonstrated the safety and feasibility of endoscopic laser welding while exposing the limitations of first generation hyaluronic acid based solders. Novel supersaturated gel based solders are currently being tested in clinical trials and appear to possess significantly improved viscoelastic properties. While laser tissue welding remains an experimental technique, continued success with these novel solder formulations may catalyze the widespread adoption of this technique for skull base repair in the near future.

  16. A Case of Skull Base Osteomyelitis with Multiple Cerebral Infarction.

    PubMed

    Miyabe, Haruka; Uno, Atsuhiko; Nakajima, Takahiro; Morizane, Natsue; Enomoto, Keisuke; Hirose, Masayuki; Hazama, Toshinori; Takenaka, Yukinori

    2016-01-01

    Skull base osteomyelitis is classically documented as an extension of malignant otitis externa. Initial presentation commonly includes aural symptoms and cranial nerve dysfunctions. Here we present a case that emerged with multiple infarctions in the right cerebrum. A male in his 70s with diabetes mellitus and chronic renal failure presented with left hemiparesis. Imaging studies showed that blood flow in the carotid artery remained at the day of onset but was totally occluded 7 days later. However, collateral blood supply prevented severe infarction. These findings suggest that artery-to-artery embolization from the petrous and/or cavernous portion of the carotid artery caused the multiple infarctions observed on initial presentation. Osteomyelitis of the central skull base was diagnosed on the basis of the following findings taken together: laboratory results showing high levels of inflammation, presence of Pseudomonas aeruginosa in the otorrhea and blood culture, multiple cranial nerve palsies that appeared later, the bony erosion observed on CT, and the mass lesion on MRI. Osteomyelitis was treated successfully by long-term antibiotic therapy; however, the patient experienced cefepime-induced neurotoxicity during therapy. The potential involvement of the internal carotid artery in this rare and life-threatening disease is of particular interest in this case. PMID:27597916

  17. Fractured Surface

    NASA Technical Reports Server (NTRS)

    2005-01-01

    [figure removed for brevity, see original site] Context image for PIA03084 Fractured Surface

    These fractures and graben are part of Gordii Fossae, a large region that has undergone stresses which have cracked the surface.

    Image information: VIS instrument. Latitude 16.6S, Longitude 234.3E. 18 meter/pixel resolution.

    Note: this THEMIS visual image has not been radiometrically nor geometrically calibrated for this preliminary release. An empirical correction has been performed to remove instrumental effects. A linear shift has been applied in the cross-track and down-track direction to approximate spacecraft and planetary motion. Fully calibrated and geometrically projected images will be released through the Planetary Data System in accordance with Project policies at a later time.

    NASA's Jet Propulsion Laboratory manages the 2001 Mars Odyssey mission for NASA's Office of Space Science, Washington, D.C. The Thermal Emission Imaging System (THEMIS) was developed by Arizona State University, Tempe, in collaboration with Raytheon Santa Barbara Remote Sensing. The THEMIS investigation is led by Dr. Philip Christensen at Arizona State University. Lockheed Martin Astronautics, Denver, is the prime contractor for the Odyssey project, and developed and built the orbiter. Mission operations are conducted jointly from Lockheed Martin and from JPL, a division of the California Institute of Technology in Pasadena.

  18. Modified three-dimensional skull base model with artificial dura mater, cranial nerves, and venous sinuses for training in skull base surgery: technical note.

    PubMed

    Mori, Kentaro; Yamamoto, Takuji; Oyama, Kazutaka; Ueno, Hideaki; Nakao, Yasuaki; Honma, Keiichirou

    2008-12-01

    Experience with dissection of the cavernous sinus and the temporal bone is essential for training in skull base surgery, but the opportunities for cadaver dissection are very limited. A modification of a commercially available prototype three-dimensional (3D) skull base model, made by a selective laser sintering method and incorporating surface details and inner bony structures such as the inner ear structures and air cells, is proposed to include artificial dura mater, cranial nerves, venous sinuses, and the internal carotid artery for such surgical training. The transpetrosal approach and epidural cavernous sinus surgery (Dolenc's technique) were performed on this modified model using a high speed drill or ultrasonic bone curette under an operating microscope. The model could be dissected in almost the same way as a real cadaver. The modified 3D skull base model provides a good educational tool for training in skull base surgery.

  19. Growing Plants in School.

    ERIC Educational Resources Information Center

    Salt, Bernard

    1990-01-01

    Background information on the methods and varieties used to demonstrate the cultivation of plants without the use of chemical pesticides is provided. Discussed are species and variety selection, growing plants from seed and from seedlings, soil preparation, using cuttings, useful crops, and pest control. (CW)

  20. GROWING SEEDS, TEACHER'S GUIDE.

    ERIC Educational Resources Information Center

    Elementary Science Study, Newton, MA.

    THIS TEACHER'S GUIDE IS DESIGNED FOR USE WITH AN ELEMENTARY SCIENCE STUDY UNIT, "GROWING SEEDS," IN WHICH SUCH BASIC SCIENCE SKILLS AND PROCESSES AS MEASUREMENT, OBSERVATION, AND HYPOTHESIS FORMATION ARE INTRODUCED THROUGH STUDENT ACTIVITIES INVOLVING SEEDS, GERMINATION, AND SEEDLING GROWTH. THE MATERIALS WERE DEVELOPED FOR USE IN ELEMENTARY…

  1. Growing Up with "1984."

    ERIC Educational Resources Information Center

    Franza, August

    1983-01-01

    Relates changing student reaction to George Orwell's "1984" over 20 years of teaching. Finds present high school students' acceptance of Orwell's bleak world vision both a sign of student honesty and a frightening indication of the growing reality of the book. (MM)

  2. Growing Backyard Textiles

    ERIC Educational Resources Information Center

    Nelson, Eleanor Hall

    1975-01-01

    For those involved in creative work with textiles, the degree of control possible in texture, finish, and color of fiber by growing and processing one's own (perhaps with students' help) can make the experience rewarding. The author describes the processes for flax and nettles and gives tips on necessary equipment. (Author/AJ)

  3. Growing through Literature.

    ERIC Educational Resources Information Center

    Thomas, Barbara J.

    "Growing through Literature" is a curriculum using Joan M. and Erik H. Erikson's theory of the Life Cycle as a structure for selecting and teaching literature to inner-city high school students at Brighton High School in Massachusetts. The program consists of four component parts: Journals, Selected Stories, Discussion, and Autobiography. By…

  4. And Away We Grow!

    ERIC Educational Resources Information Center

    Zeece, Pauline Davey

    1994-01-01

    Notes the difficulty of developing and managing a child care business well. Describes Sharlit and McConnell's (1989) five-phase model of business growth as it might apply to a growing child care program. The phases of development described are creativity; direction; delegation; coordination; and collaboration. (TJQ)

  5. A Growing Phenomenon.

    ERIC Educational Resources Information Center

    Gwynn, Mary Loleta

    1988-01-01

    Describes the "Grow Lab" program which is sponsored by the National Gardening Association. Discusses how eight square feet of classroom space are converted into a mini-ecosystem. Mentions the development of a curriculum guide to accompany the indoor garden. (TW)

  6. Closed reduction of mandibular condyle fractures using C-arm fluoroscopy: a technical note.

    PubMed

    Imai, Tomoaki; Michizawa, Masahiro; Yamamoto, Naofumi; Kai, Tatsuro

    2013-01-01

    We describe a C-arm technique for mandibular condylar fractures in an anatomic study using a model skull and show its feasibility in a clinical case. The C-arm allowed posterior-anterior visualization of the condylar process. The X-ray axis was canted ∼15 degrees cranially to the Frankfort horizontal line. The skull's sagittal plane was rotated ∼15 degrees ipsilaterally to the X-ray axis. This technique facilitates clear visualization of the condylar neck with easy, flexible, and timely adjustments. In selected cases, this method would convert the clinical settings of the condylar fracture pattern to that which would not be amenable to an open approach, making possible minimally invasive surgical procedures.

  7. [The Base of the Skull. Rudolf Virchow between Pathology and Anthropology].

    PubMed

    Seemann, Sophie

    2016-01-01

    Throughout his scientific career, the pathologist and anthropologist Rudolf Virchow (1821-1902) examined countless skulls, gradually changing his perspective on this object of research. Initially, he was mainly concerned with pathologically deformed skulls. From the 1850s onwards, he gradually developed a more anthropological approach, and anthropology increasingly came to dominate his scientific interest. This article shows how different influences became central for the establishment of his specific and dynamic model of the human skull development and its successful application in anthropology. Crucial for this process were Virchow's collaboration with his teacher Robert Froriep (1804-1861) in the department of pathology of the Charité, his research on cretinism and rickets, as well as his description of the base of the skull as the center of skull development. His research work was attended by and showed a reciprocal interaction with the buildup of large skull collections. This article uses Virchow's original publications on skull pathology as well as his still preserved skull specimens from the collection of the Berlin Museum of Medical History at the Charité for an integrated text and object based analysis.

  8. How We Got Here: Evolutionary Changes in Skull Shape in Humans & Their Ancestors

    ERIC Educational Resources Information Center

    Price, Rebecca M.

    2012-01-01

    This activity uses inquiry to investigate how large changes in shape can evolve from small changes in the timing of development. Students measure skull shape in fetal, infant, juvenile, and adult chimpanzees and compare them to adult skulls of "Homo sapiens," "Homo erectus," and "Australopithecus afarensis." They conclude by re-interpreting their…

  9. Skull mechanics and the evolutionary patterns of the otic notch closure in capitosaurs (Amphibia: Temnospondyli).

    PubMed

    Fortuny, Josep; Marcé-Nogué, Jordi; Gil, Lluis; Galobart, Angel

    2012-07-01

    Capitosaurs were among the largest amphibians that have ever lived. Their members displayed an amphibious lifestyle. We provide new information on functional morphology data, using finite element analysis (FEA) which has palaeoecological implications for the group. Our analyses included 17 taxa using (2D) plate models to test four loading cases (bilateral, unilateral and lateral bitings and skull raising system simulation). Our results demonstrates that, when feeding, capitosaurs concentrated the stress at the circumorbital region of the capitosaur skull and cranial sutures probably played a key role in dissipating and absorbing the stress generated during biting. Basal members (as Wetlugasaurus) were probably less specialized forms, while during Middle- and Late Triassic the group radiated into different ecomorphotypes with closed otic notch forms (as Cyclotosaurus) resulting in the strongest skulls during biting. Previous interpretations discussed a trend from an open to closed otic notch associated with lateral repositioning of the tabular horns, but the analysis of the skull-raising system reveals that taxa exhibiting posteriorly directed tabular horns display similar results during skull raising to those of closed otic notch taxa. Our results suggest that various constraints besides otic notch morphology, such as the elongation of the tabular horns, snout length, skull width and position, and size of the orbits affect the function of the skull. On the light of our results, capitosaur skull showed a trend to reduce the stresses and deformation during biting. Capitosaurs could be considered crocodilian analogues as they were top-level predators in fluvial and brackish Triassic ecosystems.

  10. Combined finite element and multibody dynamics analysis of biting in a Uromastyx hardwickii lizard skull.

    PubMed

    Moazen, M; Curtis, N; Evans, S E; O'Higgins, P; Fagan, M J

    2008-11-01

    Lizard skulls vary greatly in shape and construction, and radical changes in skull form during evolution have made this an intriguing subject of research. The mechanics of feeding have surely been affected by this change in skull form, but whether this is the driving force behind the change is the underlying question that we are aiming to address in a programme of research. Here we have implemented a combined finite element analysis (FEA) and multibody dynamics analysis (MDA) to assess skull biomechanics during biting. A skull of Uromastyx hardwickii was assessed in the present study, where loading data (such as muscle force, bite force and joint reaction) for a biting cycle were obtained from an MDA and applied to load a finite element model. Fifty load steps corresponding to bilateral biting towards the front, middle and back of the dentition were implemented. Our results show the importance of performing MDA as a preliminary step to FEA, and provide an insight into the variation of stress during biting. Our findings show that higher stress occurs in regions where cranial sutures are located in functioning skulls, and as such support the hypothesis that sutures may play a pivotal role in relieving stress and producing a more uniform pattern of stress distribution across the skull. Additionally, we demonstrate how varying bite point affects stress distributions and relate stress distributions to the evolution of metakinesis in the amniote skull.

  11. Brief communication: the skull attributed to Mozart--craniosynostosis or not?

    PubMed

    Hauser, G; Kritscher, H

    1994-06-01

    The results of a detailed morphological analysis of the skull attributed to Mozart are presented which refute a recent claim that the skull as well as several of Mozart's portraits show indications of uncomplicated trigonocephaly. These indications according to the present analysis are within the limits of normal variation and derive from retention of part of the long arm of the anterior fontanelle.

  12. [The Base of the Skull. Rudolf Virchow between Pathology and Anthropology].

    PubMed

    Seemann, Sophie

    2016-01-01

    Throughout his scientific career, the pathologist and anthropologist Rudolf Virchow (1821-1902) examined countless skulls, gradually changing his perspective on this object of research. Initially, he was mainly concerned with pathologically deformed skulls. From the 1850s onwards, he gradually developed a more anthropological approach, and anthropology increasingly came to dominate his scientific interest. This article shows how different influences became central for the establishment of his specific and dynamic model of the human skull development and its successful application in anthropology. Crucial for this process were Virchow's collaboration with his teacher Robert Froriep (1804-1861) in the department of pathology of the Charité, his research on cretinism and rickets, as well as his description of the base of the skull as the center of skull development. His research work was attended by and showed a reciprocal interaction with the buildup of large skull collections. This article uses Virchow's original publications on skull pathology as well as his still preserved skull specimens from the collection of the Berlin Museum of Medical History at the Charité for an integrated text and object based analysis. PMID:27476256

  13. Combined finite element and multibody dynamics analysis of biting in a Uromastyx hardwickii lizard skull

    PubMed Central

    Moazen, M; Curtis, N; Evans, S E; O'Higgins, P; Fagan, M J

    2008-01-01

    Lizard skulls vary greatly in shape and construction, and radical changes in skull form during evolution have made this an intriguing subject of research. The mechanics of feeding have surely been affected by this change in skull form, but whether this is the driving force behind the change is the underlying question that we are aiming to address in a programme of research. Here we have implemented a combined finite element analysis (FEA) and multibody dynamics analysis (MDA) to assess skull biomechanics during biting. A skull of Uromastyx hardwickii was assessed in the present study, where loading data (such as muscle force, bite force and joint reaction) for a biting cycle were obtained from an MDA and applied to load a finite element model. Fifty load steps corresponding to bilateral biting towards the front, middle and back of the dentition were implemented. Our results show the importance of performing MDA as a preliminary step to FEA, and provide an insight into the variation of stress during biting. Our findings show that higher stress occurs in regions where cranial sutures are located in functioning skulls, and as such support the hypothesis that sutures may play a pivotal role in relieving stress and producing a more uniform pattern of stress distribution across the skull. Additionally, we demonstrate how varying bite point affects stress distributions and relate stress distributions to the evolution of metakinesis in the amniote skull. PMID:19014357

  14. Multiwell fracturing experiments. [Nitrogen foam fracture treatment

    SciTech Connect

    Warpinski, N.

    1985-01-01

    The objective of the Multiwell fracturing experiments is to test and develop the technology for the efficient stimulation of tight, lenticular gas sands. This requires basic understanding of: (1) fracture behavior and geometry in this complex lithologic environment, and (2) subsequent production into the created fracture. The intricate interplay of the hydraulic fracture with the lens geometry, the internal reservoir characteristics (fractures, reservoir breaks, etc.), the in situ stresses, and the mechanical defects (fracture, bedding, etc.) need to be defined in order to develop a successful stimulation program. The stimulation phase of the Multiwell Experiment is concerned with: (1) determining important rock/reservoir properties that influence or control fracture geometry and behavior, (2) designing fracture treatments to achieve a desired size and objectives, and (3) conducting post-treatment analyses to evaluate the effectiveness of the treatment. Background statement, project description, results and evaluation of future plans are presented. 5 refs., 2 figs., 2 tabs.

  15. Experimental study of transmission of a pulsed focused beam through a skull phantom in nonlinear regime

    NASA Astrophysics Data System (ADS)

    Tsysar, S. A.; Nikolaeva, A. V.; Svet, V. D.; Khokhlova, V. A.; Yuldashev, P. V.; Sapozhnikov, O. A.

    2015-10-01

    In the paper the use of receiving and radiating system, which allows to determine the parameters of bone by nonlinear pulse-echo technique and to image of brain structures through the skull bones, was proposed. Accuracy of the skull bone characterization is due to higher measured harmonic and is significantly better than in linear case. In the experimental part focused piezoelectric transducer with diameter 100 mm, focal distance 100 mm, the frequency of 1.092 MHz was used. It was shown that skull bone profiling can be performed with the use of 3rd harmonic since 1st harmonic can be used for visualization of the underlying objects. The use of wideband systems for both skull profiling and brain visualization is restricted by skull attenuation and resulting low effective sensitivity.

  16. Alterations of skull bones found in anencephalic skeletons from an identified osteological collection. Two case reports.

    PubMed

    Irurita, Javier; Alemán, Inmaculada; Viciano, Joan; López-Lázaro, Sandra; Botella, Miguel Cecilio

    2015-07-01

    One of the most common conditions during fetal development is anencephaly, which often involves many identification difficulties in the context of physical anthropology, as it causes severe skull challenges. In this paper, we describe the alterations found in the skulls of two perinatal individuals with anencephaly from the osteological collection of identified infants in the Anthropology Laboratory of the University of Granada, Spain. Both subjects of study are in perfect state of preservation. Despite the severe malformations, all skull bones have been targeted and identified, as the possibility of studying a subject with a complete, articulated, and partially mummified skull; the other was disjointed and well preserved. The skull bones of these two individuals affected with anencephaly have been described in detail, allowing this pathological condition to be identified in skeletonized individuals in archaeological or forensic contexts, in cases where these bones did not have anatomical connection or when these were taphonomically altered.

  17. Alterations of skull bones found in anencephalic skeletons from an identified osteological collection. Two case reports.

    PubMed

    Irurita, Javier; Alemán, Inmaculada; Viciano, Joan; López-Lázaro, Sandra; Botella, Miguel Cecilio

    2015-07-01

    One of the most common conditions during fetal development is anencephaly, which often involves many identification difficulties in the context of physical anthropology, as it causes severe skull challenges. In this paper, we describe the alterations found in the skulls of two perinatal individuals with anencephaly from the osteological collection of identified infants in the Anthropology Laboratory of the University of Granada, Spain. Both subjects of study are in perfect state of preservation. Despite the severe malformations, all skull bones have been targeted and identified, as the possibility of studying a subject with a complete, articulated, and partially mummified skull; the other was disjointed and well preserved. The skull bones of these two individuals affected with anencephaly have been described in detail, allowing this pathological condition to be identified in skeletonized individuals in archaeological or forensic contexts, in cases where these bones did not have anatomical connection or when these were taphonomically altered. PMID:25416960

  18. Experimental study of transmission of a pulsed focused beam through a skull phantom in nonlinear regime

    SciTech Connect

    Tsysar, S. A. Nikolaeva, A. V.; Khokhlova, V. A.; Yuldashev, P. V.; Svet, V. D.; Sapozhnikov, O. A.

    2015-10-28

    In the paper the use of receiving and radiating system, which allows to determine the parameters of bone by nonlinear pulse-echo technique and to image of brain structures through the skull bones, was proposed. Accuracy of the skull bone characterization is due to higher measured harmonic and is significantly better than in linear case. In the experimental part focused piezoelectric transducer with diameter 100 mm, focal distance 100 mm, the frequency of 1.092 MHz was used. It was shown that skull bone profiling can be performed with the use of 3rd harmonic since 1st harmonic can be used for visualization of the underlying objects. The use of wideband systems for both skull profiling and brain visualization is restricted by skull attenuation and resulting low effective sensitivity.

  19. Proximal fifth metatarsal fractures.

    PubMed

    Ramponi, Denise R

    2013-01-01

    The most common fracture of the foot is a fracture of the proximal fifth metatarsal. In general, there are 3 types of fractures involving the proximal fifth metatarsal area, including a proximal diaphyseal stress fracture, a Jones fracture, and an avulsion fracture of the tuberosity. Some fractures of the fifth metatarsal heal without difficulty, whereas some have the potential for nonunion or delayed healing. Each fracture has some variation in the anatomical location on the fifth metatarsal, the mechanism of injury, the radiographic findings, and the treatment plan. Avulsion fractures of the tuberosity often heal without difficulty, yet fractures distal to the area of insertion of the peroneus brevis tendon are prone to nonunion and delayed healing (). Differential diagnosis of a fifth metatarsal midfoot injury includes ankle sprains, midfoot sprains, plantar facial ruptures, peroneus tendon ruptures, and other foot fractures.

  20. Estimation of the skull insertion loss using an optoacoustic point source

    NASA Astrophysics Data System (ADS)

    Estrada, Héctor; Rebling, Johannes; Turner, Jake; Kneipp, Moritz; Shoham, Shy; Razansky, Daniel

    2016-03-01

    The acoustically-mismatched skull bone poses significant challenges for the application of ultrasonic and optical techniques in neuroimaging, still typically requiring invasive approaches using craniotomy or skull thinning. Optoacoustic imaging partially circumvents the acoustic distortions due to the skull because the induced wave is transmitted only once as opposed to the round trip in pulse-echo ultrasonography. To this end, the mouse brain has been successfully imaged transcranially by optoacoustic scanning microscopy. Yet, the skull may adversely affect the lateral and axial resolution of transcranial brain images. In order to accurately characterize the complex behavior of the optoacoustic signal as it traverses through the skull, one needs to consider the ultrawideband nature of the optoacoustic signals. Here the insertion loss of murine skull has been measured by means of a hybrid optoacoustic-ultrasound scanning microscope having a spherically focused PVDF transducer and pulsed laser excitation at 532 nm of a 20 μm diameter absorbing microsphere acting as an optoacoustic point source. Accurate modeling of the acoustic transmission through the skull is further performed using a Fourier-domain expansion of a solid-plate model, based on the simultaneously acquired pulse-echo ultrasound image providing precise information about the skull's position and its orientation relative to the optoacoustic source. Good qualitative agreement has been found between the a solid-plate model and experimental measurements. The presented strategy might pave the way for modeling skull effects and deriving efficient correction schemes to account for acoustic distortions introduced by an adult murine skull, thus improving the spatial resolution, effective penetration depth and overall image quality of transcranial optoacoustic brain microscopy.

  1. Macromolecular crystal growing system

    NASA Technical Reports Server (NTRS)

    Snyder, Robert S. (Inventor); Herren, Blair J. (Inventor); Carter, Daniel C. (Inventor); Yost, Vaughn H. (Inventor); Bugg, Charles E. (Inventor); Delucas, Lawrence J. (Inventor); Suddath, Fred L. (Inventor)

    1991-01-01

    A macromolecular crystal growing system especially designed for growing crystals in the low gravity of space as well as the gravity of earth includes at least one tray assembly, a carrier assembly which receives the tray, and a refrigeration-incubation module in which the carrier assembly is received. The tray assembly includes a plurality of sealed chambers with a plastic syringe and a plug means for the double tip of the syringe provided therein. Ganging mechanisms operate the syringes and plugs simultaneously in a precise and smooth operation. Preferably, the tray assemblies are mounted on ball bearing slides for smooth operation in inserting and removing the tray assemblies into the carrier assembly. The plugging mechanism also includes a loading control mechanism. A mechanism for leaving a syringe unplugged is also provided.

  2. Growing up with Retinoblastoma

    ERIC Educational Resources Information Center

    Maley, Tom

    2005-01-01

    An account is given of growing up as a child blinded as a result of a cancer of the eye known as retinoblastoma. The role of his mother is brought out, variously as a source of objective knowledge, of one's personal worth, and of the worth of other people in one's community. The strengths and weaknesses of his first school in his home area and…

  3. How to grow tomatoes.

    PubMed

    Kimura, Seisuke; Sinha, Neelima

    2008-11-01

    INTRODUCTIONTomatoes can be easily grown in a field, in a greenhouse, or in a growth cabinet. They need acidic soil (pH 6.0-6.8), a lot of light, and water. The optimum temperature for growing tomato plants and fruit is 18°C-24°C. This protocol describes how to germinate tomato seeds, cultivate adult plants, and harvest seeds from fruit.

  4. Risk factors for fracture in adult kidney transplant recipients

    PubMed Central

    Naylor, Kyla L; Zou, Guangyong; Leslie, William D; Hodsman, Anthony B; Lam, Ngan N; McArthur, Eric; Fraser, Lisa-Ann; Knoll, Gregory A; Adachi, Jonathan D; Kim, S Joseph; Garg, Amit X

    2016-01-01

    AIM: To determine the general and transplant-specific risk factors for fractures in kidney transplant recipients. METHODS: We conducted a cohort study of all adults who received a kidney-only transplant (n = 2723) in Ontario, Canada between 2002 and 2009. We used multivariable Cox proportional hazards regression to determine general and transplant-specific risk factors for major fractures (proximal humerus, forearm, hip, and clinical vertebral). The final model was established using the backward elimination strategy, selecting risk factors with a P-value ≤ 0.2 and forcing recipient age and sex into the model. We also assessed risk factors for other fracture locations (excluding major fractures, and fractures involving the skull, hands or feet). RESULTS: There were 132 major fractures in the follow-up (8.1 fractures per 1000 person-years). General risk factors associated with a greater risk of major fracture were older recipient age [adjusted hazard ratio (aHR) per 5-year increase 1.11, 95%CI: 1.03-1.19] and female sex (aHR = 1.81, 95%CI: 1.28-2.57). Transplant-specific risk factors associated with a greater risk of fracture included older donor age (5-year increase) (aHR = 1.09, 95%CI: 1.02-1.17) and end-stage renal disease (ESRD) caused by diabetes (aHR = 1.72, 95%CI: 1.09-2.72) or cystic kidney disease (aHR = 1.73, 95%CI: 1.08-2.78) (compared to glomerulonephritis as the reference cause). Risk factors across the two fracture locations were not consistent (major fracture locations vs other). Specifically, general risk factors associated with an increased risk of other fractures were diabetes and a fall with hospitalization prior to transplantation, while length of time on dialysis, and renal vascular disease and other causes of ESRD were the transplant-specific risk factors associated with a greater risk of other fractures. CONCLUSION: Both general and transplant-specific risk factors were associated with a higher risk of fractures in kidney transplant

  5. Fracturing of ductile anisotropic multilayers: influence of material strength

    NASA Astrophysics Data System (ADS)

    Gomez-Rivas, E.; Griera, A.; Llorens, M.-G.

    2015-01-01

    Fractures in rocks deformed under dominant ductile conditions typically form simultaneously with viscous flow. Material strength plays a fundamental role on fracture development in such cases, since fracture propagation can be strongly reduced by the high energy absorption of the material. Additionally, the degree and nature of anisotropy can influence the orientation and type of resulting fractures. In this study, four plasticine multilayer models have been deformed under coaxial boundary conditions to investigate the influence of strength and anisotropy on the formation of fracture networks. The experiments were made of different mixtures and presented two types of anisotropy: composite and composite-intrinsic. The transition from non-localised deformation to systems where fracture networks control deformation accommodation is determined by the ability of the material to dissipate the external work and relax the elastic strain during loading, either by viscous flow or by coeval flow and failure. Tension cracks grow in experiments with composite anisotropy, giving rise to a network of shear fractures when they collapse and coalesce with progressive deformation. The presence of an additional intrinsic anisotropy enhances the direct nucleation of shear fractures, whose propagation and final length depend on the rigidity of the medium. Material strength increases the fracture maximum displacement (dmax) to fracture length (L) ratio, and the resulting values are significantly higher than those from fractures in elastic-brittle rocks. This is associated with the low propagation rates of fractures in rocks undergoing ductile deformation.

  6. Fracturing of ductile anisotropic multilayers: influence of material strength

    NASA Astrophysics Data System (ADS)

    Gomez-Rivas, E.; Griera, A.; Llorens, M.-G.

    2015-05-01

    Fractures in rocks deformed under dominant ductile conditions typically form simultaneously with viscous flow. Material strength plays a fundamental role during fracture development in such systems, since fracture propagation can be strongly reduced if the material accommodates most of the deformation by viscous flow. Additionally, the degree and nature of anisotropy can influence the orientation and type of resulting fractures. In this study, four plasticine multilayer models have been deformed under coaxial boundary conditions to investigate the influence of strength and anisotropy on the formation of fracture networks. The experiments were made of different mixtures and had two types of anisotropy: composite and composite-intrinsic. The transition from non-localised deformation to systems where fracture networks control deformation accommodation is determined by the ability of the material to dissipate the external work and relax the elastic strain during loading either by viscous flow or by coeval flow and failure. Tension cracks grow in experiments with composite anisotropy, giving rise to a network of shear fractures when they collapse and coalesce with progressive deformation. The presence of an additional intrinsic anisotropy enhances the direct nucleation of shear fractures, the propagation and final length of which depend on the rigidity of the medium. Material strength increases the fracture maximum displacement (dmax) to fracture length (L) ratio, and the resulting values are significantly higher than those from fractures in elastic-brittle rocks. This can be related to the low propagation rates of fractures in rocks undergoing ductile deformation.

  7. A miniaturized artificial mastoid using a skull simulator.

    PubMed

    Stenfelt, S P; Håkansson, B E

    1998-01-01

    A miniaturized artificial mastoid of size and weight that allow calibration and measurement of bone conduction hearing aids in a conventional audiometric soundproof box has been developed. Its level of mechanical impedance corresponds to the standard IEC 373 (1990) within the frequency range 250 Hz to 8 kHz. The miniaturized artificial mastoid consists of three parts: coupler, skull simulator (TU-1000), and an external electrical correction filter. The coupler is a highly damped mass-spring system designed to give the miniaturized artificial mastoid mechanical impedance in accordance with the standard IEC 373 (1990). It was found that the miniaturized artificial mastoid yielded results that are in correspondence with results obtained with the Brüel & Kjaer type 4930 artificial mastoid for frequencies above 450 Hz. Thus, at these frequencies, the miniaturized artificial mastoid can be used for audiometer calibration as well as measurement of bone conduction hearing aids.

  8. Bilateral elongated mandibular coronoid process in an Anatolian skull

    PubMed Central

    Çorumlu, Ufuk; Demir, Mehmet Tevfik; Pirzirenli, Mennan Ece

    2016-01-01

    Elongation or hyperplasia of coronoid process of mandible is rare condition characterized by abnormal bone development which cause malocclusion and the limited mouth opening. In this study, in an Anatolian skull, a case of bilateral elongation of mandibular coronoid process was presented. Levandoski panographic analysis was performed on the panoramic radiographie to determine the hyperplasia of the coronoid process. The right condylar process was exactly hyperplastic. The measurements of Kr-Go/Cd-Go were 95.10 mm/79.03 mm on right side and 97.53 mm/87.80 mm on left side. The ratio of Kr-Go/Cd-Go on the right side was 1.20. Elongated coronoid process is one of the factors cause mandibular hypomobility, it as reported here might lead to limited mouth opening. The knowledge of this variation or abnormality can be useful for the radiologist and surgeons and prevent misdiagnosis. PMID:27722017

  9. Giant juvenile nasopharyngeal angiofibroma: management by skull-base surgery.

    PubMed

    Donald, Paul J; Enepikedes, Danny; Boggan, James

    2004-07-01

    From 1977 to 2001, 5 patients were seen with giant angiofibromas that had intracranial penetration. Three of these had involvement of the cavernous sinus with angiographic evidence of significant blood supply to the tumor. We attempted complete tumor removal in all patients via a skull-base procedure. The infratemporal fossa/middle fossa approach was used in 3 patients, an anterior craniofacial approach in 1, and an anterior subcranial approach in 1. Complete tumor removal was achieved in 4 patients and incomplete excision in 1. The latter was attempted with an anterior subcranial approach but required an infratemporal fossa/middle fossa approach for completion because of unanticipated cavernous sinus involvement. The patient declined further surgery. This was the only patient who had persistent disease. Preoperative and intraoperative management, blood loss, complications, and residual effects are described.

  10. Management of Battlefield Injuries to the Skull Base.

    PubMed

    Stevens, Jayne R; Brennan, Joseph

    2016-10-01

    High velocity skull base injuries on the battlefield are unique in comparison to most civilian sector trauma. With more than 43,000 United States military personnel injuries during Operations Iraqi Freedom (OIF) and Enduring Freedom (OEF), the most recent conflicts in Iraq and Afghanistan have significantly expanded the understanding of the physiology of modern battlefield trauma and how to appropriately address these injuries. The acute care principles of effective triage, airway management, and hemorrhage control in these injuries can be life saving and are reviewed here. Specific injury patterns and battlefield examples are reviewed as well, with a review of some of the lessons learned while providing care in a deployed setting. Utilization of the knowledge learned in Iraq and Afghanistan, which have improved casualty care of deployed service members, can be used both in future military conflicts and in civilian trauma care. PMID:27648400

  11. Factors for tumor progression in patients with skull base chordoma.

    PubMed

    Wang, Liang; Tian, Kaibing; Wang, Ke; Ma, Junpeng; Ru, Xiaojuan; Du, Jiang; Jia, Guijun; Zhang, Liwei; Wu, Zhen; Zhang, Junting

    2016-09-01

    Skull base chordoma is a rare and fatal disease, recurrence of which is inevitable, albeit variable. We aimed to investigate the clinicopathologic features of disease progression, identify prognostic factors, and construct a nomogram for predicting progression in individual patients. Data of 229 patients with skull base chordoma treated by one institution between 2005 and 2014 were retrieved and grouped as primary and recurrent. Kaplan-Meier survival of progression was estimated, taking competing risks into account. Multivariable Cox regression was used to investigate survival predictors. The primary group consisted by 183 cases, gained more benefits on 5-year progression-free survival (PFS) (51%) and mean PFS time (66.9 months) than the recurrent group (46 cases), in which 5-year postrecurrent PFS was 14%, and mean postrecurrent PFS time was 29.5 months. In the primary group, visual deficits, pathological subtypes, extent of bone invasion, preoperative Karnofsky performance scale (KPS) score, and variation in perioperative KPS were identified as independent predictors of PFS. A nomogram to predict 3-year and 5-year PFS consisted of these factors, was well calibrated and had good discriminative ability (adjusted Harrell C statistic, 0.68). In the recurrent group, marginal resection (P = 0.018) and adjuvant radiotherapy (P = 0.043) were verified as protective factors associated with postrecurrent PFS. Factors for tumor progression demonstrated some differences between primary and recurrent cases. The nomogram appears useful for risk stratification of tumor progression in primary cases. Further studies will be necessary to identify the rapid-growth histopathological subtype as an independent predictor of rapid progression.

  12. Factors for tumor progression in patients with skull base chordoma.

    PubMed

    Wang, Liang; Tian, Kaibing; Wang, Ke; Ma, Junpeng; Ru, Xiaojuan; Du, Jiang; Jia, Guijun; Zhang, Liwei; Wu, Zhen; Zhang, Junting

    2016-09-01

    Skull base chordoma is a rare and fatal disease, recurrence of which is inevitable, albeit variable. We aimed to investigate the clinicopathologic features of disease progression, identify prognostic factors, and construct a nomogram for predicting progression in individual patients. Data of 229 patients with skull base chordoma treated by one institution between 2005 and 2014 were retrieved and grouped as primary and recurrent. Kaplan-Meier survival of progression was estimated, taking competing risks into account. Multivariable Cox regression was used to investigate survival predictors. The primary group consisted by 183 cases, gained more benefits on 5-year progression-free survival (PFS) (51%) and mean PFS time (66.9 months) than the recurrent group (46 cases), in which 5-year postrecurrent PFS was 14%, and mean postrecurrent PFS time was 29.5 months. In the primary group, visual deficits, pathological subtypes, extent of bone invasion, preoperative Karnofsky performance scale (KPS) score, and variation in perioperative KPS were identified as independent predictors of PFS. A nomogram to predict 3-year and 5-year PFS consisted of these factors, was well calibrated and had good discriminative ability (adjusted Harrell C statistic, 0.68). In the recurrent group, marginal resection (P = 0.018) and adjuvant radiotherapy (P = 0.043) were verified as protective factors associated with postrecurrent PFS. Factors for tumor progression demonstrated some differences between primary and recurrent cases. The nomogram appears useful for risk stratification of tumor progression in primary cases. Further studies will be necessary to identify the rapid-growth histopathological subtype as an independent predictor of rapid progression. PMID:27546605

  13. [Congenital skull base defect causing recurrent bacterial meningitis].

    PubMed

    Berliner, Elihay; Bar Meir, Maskit; Megged, Orli

    2012-08-01

    Bacterial meningitis is a life threatening disease. Most patients will experience only one episode throughout life. Children who experience bacterial meningitis more than once, require further immunologic or anatomic evaluation. We report a 9 year old child with five episodes of bacterial meningitis due to a congenital defect of the skull base. A two and a half year old boy first presented to our medical center with pneumococcal meningitis. He was treated with antibiotics and fully recovered. Two months later he presented again with a similar clinical picture. Streptococcus pneumoniae grew in cerebrospinal fluid (CSF) culture. CT scan and later MRI of the brain revealed a defect in the anterior middle fossa floor, with protrusion of brain tissue into the sphenoidal sinus. Corrective surgery was recommended but the parents refused. Three months later, a third episode of pneumococcal meningitis occurred. The child again recovered with antibiotics and this time corrective surgery was performed. Five years later, the boy presented once again with clinical signs and symptoms consistent with bacterial meningitis. CSF culture was positive, but the final identification of the bacteria was conducted by broad spectrum 16S ribosomal RNA PCR (16S rRNA PCR) which revealed a sequence of Neisseria lactamica. CT and MRI showed recurrence of the skull base defect with encephalocele in the sphenoid sinus. The parents again refused neurosurgical intervention. A year later the patient presented with bacterial meningitis. CSF culture obtained after initiation of antibiotics was negative, but actinobacillus was identified in the CSF by 16S rRNA PCR. The patient is scheduled for neurosurgical intervention. In patients with recurrent bacterial meningitis caused by organisms colonizing the oropharynx or nasopharynx, an anatomical defect should be carefully sought and surgically repaired. PMID:23350293

  14. Pathological pelvic fracture following long-term bisphosphonate use in a 63-year-old woman

    PubMed Central

    Watson, H I; Hopper, G P; Gupta, S; Roberts, J L

    2014-01-01

    A 63-year-old woman presented with a low energy pelvic fracture, which showed no signs of healing. Initial fractures were to the right hemipelvis, later followed by a right fractured neck of femur. We present a complicated patient journey, management dilemmas and highlight the growing concern with long-term bisphosphonate treatment. PMID:25312895

  15. The Nondestructive Determination of the Aluminum Content in Pressed Skulls of Aluminum Dross

    NASA Astrophysics Data System (ADS)

    Kevorkijan, Varuzan; Škapin, Srečo Davor; Kovačec, Uroš

    2013-02-01

    During production of primary and secondary aluminum, various amounts (in some cases up to 200 kg) of aluminum dross, a mixture consisting of molten aluminum metal and different oxide compounds (the nonmetallic phase), are skimmed per tonne of molten metal. To preserve the maximum aluminum content in hot dross for further extraction, it is necessary to cool the dross immediately after skimming. One way to do this is to press the skimmed hot dross in a press. In this process, the skimmed dross is transformed into so-called pressed skulls, with characteristic geometry convenient for storage, transport, or further in-house processing. Because of its high aluminum content—usually between 30% and 70%—pressed skulls represent a valuable source of aluminum and hence are in great demand in the aluminum recycling industry. Because pressed skulls are generally valued on a free-metal recovery basis, which is influenced by the yield of recovery, or in other words, by the quality of the recycling process, it was recognized as important and useful to develop a method of fast and cost-effective nondestructive measurement of the free aluminum content in pressed skulls, independent of the technology of pressed skulls recycling. In the model developed in this work, the aluminum content in pressed skulls was expressed as a function of the pressed skulls density, the density of the nonmetallic phase, and the volume fraction of closed pores. In addition, the model demonstrated that under precisely defined conditions (i.e., skulls from the dross of the same aluminum alloy and skimmed, transported, cooled, and pressed in the same way and under the same processing conditions), when other parameters except the pressed skulls density remain constant, the aluminum content in pressed skulls can be expressed as a linear function of the pressed skulls density. Following the theoretical considerations presented in this work, a practical industrial methodology was developed for nondestructive

  16. Tibial fracture exacerbates traumatic brain injury outcomes and neuroinflammation in a novel mouse model of multitrauma.

    PubMed

    Shultz, Sandy R; Sun, Mujun; Wright, David K; Brady, Rhys D; Liu, Shijie; Beynon, Sinead; Schmidt, Shannon F; Kaye, Andrew H; Hamilton, John A; O'Brien, Terence J; Grills, Brian L; McDonald, Stuart J

    2015-08-01

    Multitrauma is a common medical problem worldwide, and often involves concurrent traumatic brain injury (TBI) and bone fracture. Despite the high incidence of combined TBI and fracture, preclinical TBI research commonly employs independent injury models that fail to incorporate the pathophysiologic interactions occurring in multitrauma. Here, we developed a novel mouse model of multitrauma, and investigated whether bone fracture worsened TBI outcomes. Male mice were assigned into four groups: sham-TBI+sham-fracture (SHAM); sham-TBI+fracture (FX); TBI+sham-fracture (TBI); and TBI+fracture (MULTI). The injury methods included a closed-skull weight-drop TBI model and a closed tibial fracture. After a 35-day recovery, mice underwent behavioral testing and magnetic resonance imaging (MRI). MULTI mice displayed abnormal behaviors in the open-field compared with all other groups. On MRI, MULTI mice had enlarged ventricles and diffusion abnormalities compared with all other groups. These changes occurred in the presence of heightened neuroinflammation in MULTI mice at 24 hours and 35 days after injury, and elevated edema and blood-brain barrier disruption at 24 hours after injury. Together, these findings indicate that tibial fracture worsens TBI outcomes, and that exacerbated neuroinflammation may be an important factor that contributes to these effects, which warrants further investigation.

  17. Fractures of the forefoot.

    PubMed

    Mandracchia, Vincent J; Mandi, Denise M; Toney, Patris A; Halligan, Jennifer B; Nickles, W Ashton

    2006-04-01

    Fractures of the forefoot are common injuries of various causes. Although not crippling, forefoot fractures can be debilitating if they go undiagnosed or are mistreated. Whenever patients complain of foot pain with ambulation or difficulty ambulating, radiographs should be taken as part of a standard routine to assess for bony pathology. This article discusses the classification and treatment of metatarsal fractures, digital and sesamoid fractures, and open fractures about the forefoot.

  18. The ontogenetic origins of skull shape disparity in the Triturus cristatus group.

    PubMed

    Cvijanović, Milena; Ivanović, Ana; Kalezić, Miloš L; Zelditch, Miriam L

    2014-09-01

    Comparative studies of ontogenies of closely related species provide insights into the mechanisms responsible for morphological diversification. Using geometric morphometrics, we investigated the ontogenetic dynamics of postlarval skull shape and disparity in three closely related crested newt species. The skull shapes of juveniles just after metamorphosis (hereafter metamorphs) and adult individuals were sampled by landmark configurations that describe the shape of the dorsal and ventral side of the newt skull, and analyzed separately. The three species differ in skull size and shape in metamorphs and adults. The ontogenies of dorsal and ventral skull differ in the orientation but not lengths of the ontogenetic trajectories. The disparity of dorsal skull shape increases over ontogeny, but that of ventral skull shape does not. Thus, modifications of ontogenetic trajectories can, but need not, increase the disparity of shape. In species with biphasic life-cycles, when ontogenetic trajectories for one stage can be decoupled from those of another, increases and decreases in disparity are feasible, but our results show that they need not occur.

  19. YURAGI: analysis for trans-skull brain visualizing by ultrasonic array probe

    NASA Astrophysics Data System (ADS)

    Yagi, N.; Oshiro, Y.; Ishikawa, O.; Hata, Y.; Kitamura, Y. T.; Yanagida, T.

    2011-06-01

    This paper proposes a YURAGI-Analysis for brain imaging under the skull. In it, we employ 1.0MHz and 0.5MHz ultrasonic waves. We consider the weighted sum of these waves and attempt to extract the skull depth and image the sulcus under it. We add 1.0MHz and 0.5MHz, and we add the waves of 1.0MHz and Gaussian noise as the YURAGI analysis. We visualize the sulcus and skull. First, we calculate the thickness of the skull from the each of two synthesized waves. The thickness is determined from the surface and bottom points determined from the wave based on fuzzy inference. The sulcus surface was extracted from B-mode images for the each of two synthesized waves. As the result using a cow scapula as the skull and steel ditch as the human sulcus, we successfully calculated skull thickness. We extracted the sulcus width within the error of 5.86 mm and depth within the error of 1.94 mm. As for imaging the sulcus under the skull, the highest effectiveness of the synthesized wave is 96.30% when the weight of 0.5MHz waves is 0.60, and the one of YURAGI-Analysis wave is 97.15% when the weight is 0.003. Thus, YURAGI-Analysis is useful to this study.

  20. An historical skull collection and its use in forensic odontology and anthropology.

    PubMed

    Sejrsen, B; Lynnerup, N; Hejmadi, M

    2005-12-01

    The Institute of Forensic Medicine, Copenhagen, houses a collection of historical skulls of unclear origin, marked with a general geographic or "racial descriptor". Would these historical skulls be of any value for the forensic odontologist and anthropologist concerned with teaching and casework? We tried to clarify this question by recording non-metric dental traits and by performing craniometric analyses. A morphological and morphometric investigation of anatomical/dental traits in 80 adult skulls was performed. For each skull four non-metric dental traits using the ASU-System and three non-metric cranial traits were recorded. Nineteen cranial measures were also taken following the FORDISC programme manual. The non-metrical data were tabulated as frequencies, and the metric data were entered in the FORDISC programme. Observed non-metric trait frequencies were compared with published data. The FORDISC programme computed a discriminatory analysis for each skull and thereby assigned the skull to the most probable ethnic category. The results for the non-metric traits showed that the traits generally followed the expected frequencies in 80% of the cases. The FORDISC programme correctly assigned ethnicity based on skull measurements in overall 70% of the cases. It was found that this historical collection does show expected dental non-metric and craniometric traits and the collection may be of value in forensic casework in terms of comparison and for teaching purposes. PMID:16353754

  1. A continuous point measure for quantifying skull deformation in medical diagnostics

    PubMed Central

    Strachan, Ben; O'Connor, Bridget; Khandoker, Ahsan

    2014-01-01

    Deformational plagiocephaly (DP) manifests in a deformed skull primarily caused by retaining a constant sleeping position in infants. Manual measures of skull asymmetry based on MRI or CT scans combined with the cranial vault asymmetry index (CVAI) provides information on the extent of asymmetry. CVAI uses four points on the skull as markers for the asymmetry index but tends to underestimate the deformity because of the lack of sampling points. Computer-based continuous-point methods may be a more objective measure with better sensitivity for the skull contour. The outline of the skull circumference of infants with confirmed cranial deformity was obtained from the literature and analysed applying the mean bending energy (MBE) obtained from the Hermitian wavelet. MBE was shown to correlate with CVAI in the current sample and has the potential to add both quantitative and visual information in 2D or 3D space for the clinician to diagnose DP. Wavelet-based continuous-point estimation of skull asymmetry is a useful method as it is more sensitive to mild deformation anywhere along the skull outline and in assessing slow but progressive improvement as a result of treatment. The broader significance is that this method can be applied to other structural pathology analysis in clinical practice. PMID:26609378

  2. An innovative transparent cranial window based on skull optical clearing An innovative transparent cranial window

    NASA Astrophysics Data System (ADS)

    Wang, J.; Zhang, Y.; Xu, T. H.; Luo, Q. M.; Zhu, D.

    2012-06-01

    Noninvasive optical methods for viewing the structural and functional organization of cortex have been playing important roles in brain research, which usually suffer from turbid skull. Various cranial window models based on surgical operation have been proposed, but have respective limitations. Here, an innovative transparent cranial window of mouse was established by topically treatment with a skull optical clearing solution (SOCS), rather than by craniotomy. Based on the experiment of optical clearing efficacy of skull in vitro, we found that the turbid skull became transparent within 25 min after application of SOCS. The USAF target is visible through the treated skull, and the calculated resolution can achieve 8.4 μm. After the in vivo skull was topically treated with SOCS, the cortical micro-vessels can be visible clearly. The quantitative analysis indicated that the minimum resolution diameter of micro-vessels in 14.4±0.8 μm through the transparent cranial window closed to that in 12.8±0.9 μm of the exposed cortical micro-vessels. Further, preliminary results from Laser Speckle Imaging demonstrated that there was no influence on cortical blood flow distribution of mouse after topically treatment with SOCS on skull. This transparent cranial window will provide a convenient model for cortex imaging in vivo, which is very significant for neuroscience research.

  3. Skull-photo superimposition and border deaths: identification through exclusion and the failure to exclude.

    PubMed

    Fenton, Todd W; Heard, Amber N; Sauer, Norman J

    2008-01-01

    We report on the application of video skull-photo superimposition as an identification method in a case from Ajo, Arizona in which five individuals died after crossing into southern Arizona from Mexico. Initial analyses at the Pima County Forensic Science Center in Tucson, Arizona determined that the disarticulated skeletal remains represented two adult Hispanic males and three adult Hispanic females. Based on biological profiles, both the males and one of the females were tentatively identified and assigned names. The other two females were too similar in age and height, making skeletal separation and identification difficult. As a result, the Michigan State University Forensic Anthropology Laboratory assisted in the identification efforts by performing video skull-photo superimposition on the two unknown females. The skulls were compared to a photograph reported to be one of the missing females. By evaluating facial proportionality and by comparing a number of morphological features of the face and skulls, one skull was excluded as a possible match and one skull was not excluded as a match to the antemortem photo. Because this case was presumed to be a closed disaster, the exclusion of one skull and the failure to exclude the other represented circumstantial identifications. PMID:18279236

  4. Tumors of the skull base in children: review of tumor types and management strategies.

    PubMed

    Tsai, Eve C; Santoreneos, Stephen; Rutka, James T

    2002-05-15

    Although many treatment strategies for skull base tumors in adults have been reported, relatively little has been reported regarding such therapies in the pediatric population. Skull base tumors in children present a therapeutic challenge because of their unique pathological composition, the constraints of the maturing skull and brain, and the small size of the patients. In this review, the authors examine the pediatric skull base lesions that occur in the anterior, middle, and posterior cranial base, focusing on unique pediatric tumors such as encepahalocele, fibrous dysplasia, esthesioneuroblastoma, craniopharyngioma, juvenile nasopharyngeal angiofibroma, cholesteatoma, chordoma, chondrosarcoma, and Ewing sarcoma. They review management strategies that include radio- and chemotherapy, as well as surgical approaches with emphasis on the modifications and complications associated with the procedures as they apply in children. Evidence for the advantages and limitations of radiotherapy, chemotherapy, and surgery as it pertains to the pediatric population will be examined. With a working knowledge of skull base anatomy and special considerations of the developing craniofacial skeleton, neurosurgeons can treat skull base lesions in children with acceptable morbidity and mortality rates. Outcomes in this population may be better than those in adults, in part because of the benign histopathology that frequently affects the pediatric skull base, as well as the plasticity of the maturing nervous system.

  5. Effect of skull contours on dose calculations in Gamma Knife Perfexion stereotactic radiosurgery.

    PubMed

    Nakazawa, Hisato; Komori, Masataka; Mori, Yoshimasa; Hagiwara, Masahiro; Shibamoto, Yuta; Tsugawa, Takahiko; Hashizume, Chisa; Kobayashi, Tatsuya

    2014-03-06

    In treatment planning of Leksell Gamma Knife (LGK) radiosurgery, the skull geometry defined by generally dedicated scalar measurement has a crucial effect on dose calculation. The LGK Perfexion (PFX) unit is equipped with a cone-shaped collimator divided into eight sectors, and its configuration is entirely different from previous model C. Beam delivery on the PFX is made by a combination of eight sectors, but it is also mechanically available from one sector with the remaining seven blocked. Hence the treatment time using one sector is more likely to be affected by discrepancies in the skull shape than that of all sectors. In addition, the latest version (Ver. 10.1.1) of the treatment planning system Leksell GammaPlan (LGP) includes a new function to directly generate head surface contouring from computed tomography (CT) images in conjunction with the Leksell skull frame. This paper evaluates change of treatment time induced by different skull models. A simple simulation using a uniform skull radius of 80 mm and anthropomorphic phantom was implemented in LGP to find the trend between dose and skull measuring error. To evaluate the clinical effect, we performed an interobserver comparison of ruler measurement for 41 patients, and compared instrumental and CT-based contours for 23 patients. In the phantom simulation, treatment time errors were less than 2% when the difference was within 3 mm. In the clinical cases, the variability of treatment time induced by the differences in interobserver measurements was less than 0.91%, on average. Additionally the difference between measured and CT-based contours was good, with a difference of -0.16% ± 0.66% (mean ±1 standard deviation) on average and a maximum of 3.4%. Although the skull model created from CT images reduced the dosimetric uncertainty caused by different measurers, these results showed that even manual skull measurement could reproduce the skull shape close to that of a patient's head within an acceptable

  6. Resolving the Location of Acoustic Point Sources Scattered Due to the Presence of a Skull Phantom

    NASA Astrophysics Data System (ADS)

    Sadler, J.; Shapoori, K.; Malyarenko, E.; DiCarlo, A.; Dech, J.; Severin, F.; Maev, R. Gr.

    This paper considers resolving the location of a foreign object in the brain without the removal of the skull bone by detecting and processing the acoustic waves emitted from the foreign object modeled as point source. The variable thickness of the skull bone causes propagation acoustic waves to be scattered in such a manner that the acoustic wave undergoes a variable time delay relative to its entry point on the skull. Matched filtering can be used to detect the acoustic wave front, the time delay variations of the skull can be corrected for, and matched filtering time reversal algorithms can then detect the location of the acoustic source. This process is examined experimentally in a water tank system containing an acoustic source, custom-made skull phantom, and receiver. The apparatus is arranged in transmission mode so that the acoustic waves are emitted from the source, scattered by the phantom, and then received by a second transducer. The skull phantom has been designed so that the acoustic properties (velocity, density, and attenuation correspond approximately to those of a typical human skull. In addition, the phantom has been molded so that the surface closest to the acoustic source has smoothly oscillating ridges and valleys and a flat outer surface, approximately modeling a real-world skull bone. The data obtained from the experiment is processed to detect and extract the scattered acoustic wave front and correct for the time of flight variations in the skull. This re-creates the approximate wave front of a point source, whose location can be resolved via a matched filtering time reversal algorithm. The results of this process are examined for cases where there is no phantom present (no scattering), and with the phantom present. Comparison of these results shows a correlation between the calculated locations of the acoustic source and the expected location.

  7. Growing Unculturable Bacteria

    PubMed Central

    2012-01-01

    The bacteria that can be grown in the laboratory are only a small fraction of the total diversity that exists in nature. At all levels of bacterial phylogeny, uncultured clades that do not grow on standard media are playing critical roles in cycling carbon, nitrogen, and other elements, synthesizing novel natural products, and impacting the surrounding organisms and environment. While molecular techniques, such as metagenomic sequencing, can provide some information independent of our ability to culture these organisms, it is essentially impossible to learn new gene and pathway functions from pure sequence data. A true understanding of the physiology of these bacteria and their roles in ecology, host health, and natural product production requires their cultivation in the laboratory. Recent advances in growing these species include coculture with other bacteria, recreating the environment in the laboratory, and combining these approaches with microcultivation technology to increase throughput and access rare species. These studies are unraveling the molecular mechanisms of unculturability and are identifying growth factors that promote the growth of previously unculturable organisms. This minireview summarizes the recent discoveries in this area and discusses the potential future of the field. PMID:22661685

  8. Nonlinear growing neutrino cosmology

    NASA Astrophysics Data System (ADS)

    Ayaita, Youness; Baldi, Marco; Führer, Florian; Puchwein, Ewald; Wetterich, Christof

    2016-03-01

    The energy scale of dark energy, ˜2 ×10-3 eV , is a long way off compared to all known fundamental scales—except for the neutrino masses. If dark energy is dynamical and couples to neutrinos, this is no longer a coincidence. The time at which dark energy starts to behave as an effective cosmological constant can be linked to the time at which the cosmic neutrinos become nonrelativistic. This naturally places the onset of the Universe's accelerated expansion in recent cosmic history, addressing the why-now problem of dark energy. We show that these mechanisms indeed work in the growing neutrino quintessence model—even if the fully nonlinear structure formation and backreaction are taken into account, which were previously suspected of spoiling the cosmological evolution. The attractive force between neutrinos arising from their coupling to dark energy grows as large as 106 times the gravitational strength. This induces very rapid dynamics of neutrino fluctuations which are nonlinear at redshift z ≈2 . Nevertheless, a nonlinear stabilization phenomenon ensures only mildly nonlinear oscillating neutrino overdensities with a large-scale gravitational potential substantially smaller than that of cold dark matter perturbations. Depending on model parameters, the signals of large-scale neutrino lumps may render the cosmic neutrino background observable.

  9. Disentangling the emerging evidence around atypical fractures.

    PubMed

    Abrahamsen, Bo; Clark, Emma M

    2012-06-01

    Atypical femur fractures are rare but a growing concern, as they are more common in patients who use bisphosphonates. The best radiology-based studies have had access to only short-term exposure data, while the studies using prescription databases with substantial long-term data did not have access to radiology reports. The interests of the patients are probably best served by reserving long-term bisphosphonate treatment for patients who are at the highest risk of osteoporotic fractures and considering drug holidays after 5 years in patients at low risk. Recent studies have further strengthened the case for active medical or surgical therapy in patients with incomplete fractures, but patient numbers are small, and randomized controlled trials may not be forthcoming in the immediate future. The recommendations made to establish an international database for such fractures have not yet been followed, and more epidemiologic and pathophysiologic research is needed.

  10. Fracture ventilation by surface winds

    NASA Astrophysics Data System (ADS)

    Nachshon, U.; Dragila, M. I.; Weisbrod, N.

    2011-12-01

    Gas exchange between the Earth subsurface and the atmosphere is an important mechanism, affecting hydrological, agricultural and environmental processes. From a hydrological aspect, water vapor transport is the most important process related to Earth-atmosphere gas exchange. In respect to agriculture, gas transport in the upper soil profile is important for soil aeration. From an environmental aspect, emission of volatile radionuclides, such as 3H, 14C and Rd from radioactive waste disposal facilities; volatile organic components from industrial sources and Rn from natural sources, all found in the upper vadose zone, can greatly affect public health when emissions occur in populated areas. Thus, it is vital to better understand gas exchange processes between the Earth's upper crust and atmosphere. Four major mechanisms are known to transfer gases between ground surface and atmosphere: (1) Diffusion; (2) Pressure gradients between ground pores and atmosphere due to changes in barometric pressure; (3) Density-driven gas flow in respond to thermal gradients in the ground; and (4) Winds above the ground surface. Herein, the wind ventilation mechanism is studied. Whereas the wind's impact on ground ventilation was explored in several studies, the physical mechanisms governing this process were hardly quantified or characterized. In this work the physical properties of fracture ventilation due to wind blowing along land surface were explored and quantified. Both field measurements and Hele-Shaw experiments under controlled conditions in the laboratory were used to study this process. It was found that winds in the range of 0.3 m/s result in fracture ventilation down to a depth of 0.2 m. As wind velocity increases, the depth of the ventilation inside the fracture increases respectively, in a linear manner. In addition, the fracture aperture also affects the depth of ventilation, which grows as fracture aperture increases. For the maximal examined aperture of 2 cm and wind

  11. Is orthopantomography reliable for TMJ diagnosis? An experimental study on a dry skull.

    PubMed

    Ruf, S; Pancherz, H

    1995-01-01

    The accuracy of orthopantomography in reproducing the temporomandibular joint area was analyzed on a dry skull. The results based on this study of a single skull revealed that the radiographic image of the temporomandibular joint did not correspond to the anatomic condylar and fossa components or to their actual relationship. To a large extent, changes in skull position affected the radiographic temporomandibular joint image, simulating anterior condylar flattening, osteophytes, narrowing of joint space, and left/right condylar asymmetry. Orthopantomography may have questionable reliability for temporomandibular joint diagnostic purposes.

  12. [The anatomy of a reduced skull model--visualisation of Leonardo da Vinci's anthropology].

    PubMed

    Ahner, E

    2008-04-01

    The article focuses on a rare example of a miniature skull of unknown origin. The profoundness of the anatomical details, conjoint with outstanding virtuosity, reminds of Leonardo da Vinci's anatomical skull studies and asks for additional interpretation beside the emblematic "memento mori"-character. Following the miscellaneous topics of his skull studies an anatomical-anthropological interpretation is proposed. For such a project the mergence of anthropology, history of medicine and history of art was mandatory. Concerning some discrepancies within the anatomical realism, the depiction of a pathology is discussed and beyond the visualisation of a historic concept of brain function.

  13. Congenital skull indentation: a case report and review of the literature

    PubMed Central

    Shamsian, Negin; Robertson, Andrew Tristan; Anslow, Philip

    2012-01-01

    Congenital depressions of the skull are rare in Western countries. The majority relate to obstetric trauma at delivery. We present a case of a congenital depression of a neonate's skull not relating to obstetric trauma. The child had an ovoid indentation behind the right coronal suture in the temperoparietal region. This skull depression was thought to relate to the position of her right hand in utero. We report her management, neuro-imaging and outcome on follow-up. A literature review is given in brief. PMID:22922910

  14. Paratrooper's Ankle Fracture: Posterior Malleolar Fracture

    PubMed Central

    Young, Ki Won; Cho, Jae Ho; Kim, Hyung Seuk; Cho, Hun Ki; Lee, Kyung Tai

    2015-01-01

    Background We assessed the frequency and types of ankle fractures that frequently occur during parachute landings of special operation unit personnel and analyzed the causes. Methods Fifty-six members of the special force brigade of the military who had sustained ankle fractures during parachute landings between January 2005 and April 2010 were retrospectively analyzed. The injury sites and fracture sites were identified and the fracture types were categorized by the Lauge-Hansen and Weber classifications. Follow-up surveys were performed with respect to the American Orthopedic Foot and Ankle Society ankle-hindfoot score, patient satisfaction, and return to preinjury activity. Results The patients were all males with a mean age of 23.6 years. There were 28 right and 28 left ankle fractures. Twenty-two patients had simple fractures and 34 patients had comminuted fractures. The average number of injury and fractures sites per person was 2.07 (116 injuries including a syndesmosis injury and a deltoid injury) and 1.75 (98 fracture sites), respectively. Twenty-three cases (41.07%) were accompanied by posterior malleolar fractures. Fifty-five patients underwent surgery; of these, 30 had plate internal fixations. Weber type A, B, and C fractures were found in 4, 38, and 14 cases, respectively. Based on the Lauge-Hansen classification, supination-external rotation injuries were found in 20 cases, supination-adduction injuries in 22 cases, pronation-external rotation injuries in 11 cases, tibiofibular fractures in 2 cases, and simple medial malleolar fractures in 2 cases. The mean follow-up period was 23.8 months, and the average follow-up American Orthopedic Foot and Ankle Society ankle-hindfoot score was 85.42. Forty-five patients (80.36%) reported excellent or good satisfaction with the outcome. Conclusions Posterior malleolar fractures occurred in 41.07% of ankle fractures sustained in parachute landings. Because most of the ankle fractures in parachute injuries were

  15. Sleep to grow smart?

    PubMed

    Volk, Carina; Huber, Reto

    2015-01-01

    Sleep is undisputable an essential part of our life, if we do not sleep enough we feel the consequences the next day. The importance of sleep for healthy brain functioning has been well studied in adults, but less is known for the role of sleep in the paediatric age. Childhood and adolescence is a critical phase for brain development. The increased need for sleep during this developmental phase fosters the growing recognition for a central role of sleep during development. In this review we summarize the findings that demonstrate a close relationship between sleep and brain maturation, discuss the consequences of insufficient sleep during childhood and adolescence and outline initial attempts that have been made in order to improve sleep in this age range. PMID:26742664

  16. Growing a market economy

    SciTech Connect

    Basu, N.; Pryor, R.J.

    1997-09-01

    This report presents a microsimulation model of a transition economy. Transition is defined as the process of moving from a state-enterprise economy to a market economy. The emphasis is on growing a market economy starting from basic microprinciples. The model described in this report extends and modifies the capabilities of Aspen, a new agent-based model that is being developed at Sandia National Laboratories on a massively parallel Paragon computer. Aspen is significantly different from traditional models of the economy. Aspen`s emphasis on disequilibrium growth paths, its analysis based on evolution and emergent behavior rather than on a mechanistic view of society, and its use of learning algorithms to simulate the behavior of some agents rather than an assumption of perfect rationality make this model well-suited for analyzing economic variables of interest from transition economies. Preliminary results from several runs of the model are included.

  17. [Fractures of the forefoot].

    PubMed

    Richter, M

    2011-10-01

    Fractures of the forefoot are common and comprise approximately two thirds of all foot fractures. Forefoot fractures are caused by direct impact or the effect of indirect force. The forces exerted can range from repetitive minor load (stress fractures) to massive destructive forces (complex trauma). The clinical course in forefoot fractures is typically more favourable than in fractures of the mid- and hindfoot. The incidence of complications like infection or pseudarthrosis is low. Exceptions are rare fractures of the proximal shaft of the fifth metatarsal and the sesamoids with higher pseudarthrosis rates. Malunited metatarsal fractures can cause painful conditions that should even be treated operatively. Differences in structure and function of the different forefoot areas and specific fracture types require an adapted management of these special injuries.

  18. Chemical characteristics and antithrombotic effect of chondroitin sulfates from sturgeon skull and sturgeon backbone.

    PubMed

    Gui, Meng; Song, Juyi; Zhang, Lu; Wang, Shun; Wu, Ruiyun; Ma, Changwei; Li, Pinglan

    2015-06-01

    Chondroitin sulfates (CSs) were extracted from sturgeon skull and backbone, and their chemical composition, anticoagulant, anti-platelet and thrombolysis activities were evaluated. The average molecular weights of CS from sturgeon skull and backbone were 38.5kDa and 49.2kDa, respectively. Disaccharide analysis indicated that the sturgeon backbone CS was primarily composed of disaccharide monosulfated in position four of the GalNAc (37.8%) and disaccharide monosulfated in position six of the GalNAc (59.6%) while sturgeon skull CS was primarily composed of nonsulfated disaccharide (74.2%). Sturgeon backbone CS showed stronger antithrombotic effect than sturgeon skull CS. Sturgeon backbone CS could significantly prolong activated partial thromboplastin time (APTT) and thrombin time (TT), inhibited ADP-induced platelet aggregation and dissolved platelet plasma clots in vitro. The results suggested that sturgeon backbone CS can be explored as a functional food with antithrombotic function.

  19. A new giant pterosaur with a robust skull from the latest cretaceous of Romania.

    PubMed

    Buffetaut, E; Grigorescu, D; Csiki, Z

    2002-04-01

    A new giant pterosaur, Hatzegopteryx thambema, nov.gen., nov.sp., from the Maastrichtian Densuş-Ciula Formation of Romania is remarkable for its very large size (estimated wing span > or = 12 m) and for the robustness of its large skull, which may have been nearly 3 m long. The stout skull bones contrast with the usually thin and slender skull elements of other pterosaurs, and raise the question of how the weight of the skull was reduced in order to make flight possible. The answer probably lies in the very peculiar internal structure of the bones, which consists of a dense network of very thin trabeculae enclosing small alveoli. This structure is reminiscent of expanded polystyrene and, like it, probably combined strength with lightness.

  20. A new giant pterosaur with a robust skull from the latest Cretaceous of Romania

    NASA Astrophysics Data System (ADS)

    Buffetaut, E.; Grigorescu, D.; Csiki, Z.

    2002-02-01

    A new giant pterosaur, Hatzegopteryx thambema, nov.gen., nov.sp., from the Maastrichtian Densuş-Ciula Formation of Romania is remarkable for its very large size (estimated wing span >=12 m) and for the robustness of its large skull, which may have been nearly 3 m long. The stout skull bones contrast with the usually thin and slender skull elements of other pterosaurs, and raise the question of how the weight of the skull was reduced in order to make flight possible. The answer probably lies in the very peculiar internal structure of the bones, which consists of a dense network of very thin trabeculae enclosing small alveoli. This structure is reminiscent of expanded polystyrene and, like it, probably combined strength with lightness.

  1. Skull typology of Byzantine dogs from the Theodosius Harbour at Yenikapi, Istanbul.

    PubMed

    Onar, V; Çakirlar, C; Janeczek, M; Kiziltan, Z

    2012-10-01

    This study presents the results of craniometric analysis of 500 Byzantine Era dog skulls from the ancient site of the Theodosius Harbour in Istanbul (modern Yenikapi neighbourhood). To determine the typology of the skulls, up to 36 craniometric measurements were taken on each specimen. Fourteen indices and ratios were calculated from the measurements. Results show that the majority (97%) of the Byzantine dogs from the Yenikapi excavations were of mesocephalic type. Only 15 of the analysed skulls (3%) were of the dolichocephalic type. Only one dog skeleton has been recovered in situ during the excavations; analysis indicates that this individual belonged to a mesocephalic type dog. Brachycephalic dog skulls were absent in the samples studied from Byzantine Yenikapi. The results give important insight in continuities and discontinuities in dog-breeding traditions from the Roman to the Byzantine Eras, and between the West and the East during Medieval times.

  2. Reflection mode photoacoustic imaging through infant skull toward noninvasive imaging of neonatal brains

    NASA Astrophysics Data System (ADS)

    Wang, Xueding; Fowlkes, J. Brian; Chamberland, David L.; Xi, Guohua; Carson, Paul L.

    2009-02-01

    The feasibility of transcranial imaging of neonatal brains with reflection mode photoacoustic technology has been explored. By using unembalmed infant skulls and fresh canine brains, experiments have been conducted to examine the ultrasound and light attenuation in the skull bone as well as consequent photoacoustic images through the skull. Mapping of blood vessels in a transcranial manner has been successfully achieved by employing the raster scan of a single-element transducer or a 2D PVDF array transducer. Experimental results indicate that noninvasive photoacoustic imaging of neonatal brain with a depth of 2 cm or more beneath the skull is feasible when working with near-infrared light. This study suggests that the emerging photoacoustic technology may become a powerful tool in the future for noninvasive diagnosis, monitoring and prognosis of disorders in prenatal or neonatal brains.

  3. Physical and technical aspects of ultrasonic brain imaging through thick skull bones: 2. Experimental studies

    NASA Astrophysics Data System (ADS)

    Baykov, S. V.; Babin, L. V.; Molotilov, A. M.; Neiman, S. I.; Riman, V. V.; Svet, V. D.; Selyanin, A. I.

    2003-07-01

    Experimental results of the ultrasonic imaging of brain structures through thick skull bones are presented. The model imaging system and the ultrasonic images of blood vessel models and images obtained in vivo for some brain structures are described.

  4. Temporalis muscle hypertrophy and reduced skull eccentricity in Duchenne muscular dystrophy.

    PubMed

    Straathof, C S M; Doorenweerd, N; Wokke, B H A; Dumas, E M; van den Bergen, J C; van Buchem, M A; Hendriksen, J G M; Verschuuren, J J G M; Kan, H E

    2014-10-01

    Muscle hypertrophy and muscle weakness are well known in Duchenne muscular dystrophy. Decreased muscle force can have secondary effects on skeletal growth and development such as facial and dental morphology changes. In this study, we quantified temporal muscle thickness, circumference, and eccentricity of the skull and the head on T1-weighted magnetic resonance imaging (MRI) scans of the head of 15 Duchenne muscular dystrophy patients and 15 controls. Average temporal muscle thickness was significantly increased in patients (12.9 ± 5.2 mm) compared to controls (6.8 ± 1.4 mm) (P < .0001), whereas the shape of the skull was significantly rounder compared to controls. Temporal muscle thickness and skull eccentricity were significantly negatively correlated in patients, and positively in controls. Hypertrophy of the temporal muscles and changes in skull eccentricity appear to occur early in the course of Duchenne muscular dystrophy. Further studies in younger patients are needed to confirm a causal relationship.

  5. Digital preparation and osteology of the skull of Lesothosaurus diagnosticus (Ornithischia: Dinosauria)

    PubMed Central

    Witmer, Lawrence M.; Barrett, Paul M.

    2015-01-01

    Several skulls of the ornithischian dinosaur Lesothosaurus diagnosticus (Lower Jurassic, southern Africa) are known, but all are either incomplete, deformed, or incompletely prepared. This has hampered attempts to provide a comprehensive description of skull osteology in this crucial early dinosaurian taxon. Using visualization software, computed tomographic scans of the Lesothosaurus syntypes were digitally segmented to remove matrix, and identify and separate individual cranial and mandibular bones, revealing new anatomical details such as sutural morphology and the presence of several previously undescribed elements. Together with visual inspection of exposed skull bones, these CT data enable a complete description of skull anatomy in this taxon. Comparisons with our new data suggest that two specimens previously identified as Lesothosaurus sp. (MNHN LES 17 and MNHN LES 18) probably represent additional individuals of Lesothosaurus diagnosticus. PMID:26713245

  6. Digital preparation and osteology of the skull of Lesothosaurus diagnosticus (Ornithischia: Dinosauria).

    PubMed

    Porro, Laura B; Witmer, Lawrence M; Barrett, Paul M

    2015-01-01

    Several skulls of the ornithischian dinosaur Lesothosaurus diagnosticus (Lower Jurassic, southern Africa) are known, but all are either incomplete, deformed, or incompletely prepared. This has hampered attempts to provide a comprehensive description of skull osteology in this crucial early dinosaurian taxon. Using visualization software, computed tomographic scans of the Lesothosaurus syntypes were digitally segmented to remove matrix, and identify and separate individual cranial and mandibular bones, revealing new anatomical details such as sutural morphology and the presence of several previously undescribed elements. Together with visual inspection of exposed skull bones, these CT data enable a complete description of skull anatomy in this taxon. Comparisons with our new data suggest that two specimens previously identified as Lesothosaurus sp. (MNHN LES 17 and MNHN LES 18) probably represent additional individuals of Lesothosaurus diagnosticus. PMID:26713245

  7. Fungus-growing ants.

    PubMed

    Weber, N A

    1966-08-01

    Fungus-growing ants (Attini) are in reality unique fungus-culturing insects.There are several hundred species in some dozen genera, of which Acromyrmex and Atta are the conspicuous leaf-cutters. The center of their activities is the fungus garden, which is also the site of the queen and brood. The garden, in most species, is made from fresh green leaves or other vegetal material. The ants forage for this, forming distinct trails to the vegetation that is being harvested. The cut leaves or other substrate are brought into the nest and prepared for the fungus. Fresh leaves and flowers are cut into pieces a millimeter or two in diameter; the ants form them into a pulpy mass by pinching them with the mandibles and adding saliva. Anal droplets are deposited on the pieces, which are then forced into place in the garden. Planting of the fungus is accomplished by an ant's picking up tufts of the adjacent mycelium and dotting the surface of the new substrate with it. The combination of salivary and anal secretions, together with the constant care given by the ants, facilitates the growth of the ant fungus only, despite constant possibilities for contamination. When the ants are removed, alien fungi and other organisms flourish. A mature nest of Atta Sexdens may consist of 2000 chambers, some temporarily empty, some with refuse, and the remainder with fungus gardens. Thousands of kilograms of fresh leaves will have been used. A young laboratory colony of Atta cephalotes will use 1 kilogram of fresh leaves for one garden. The attines are the chief agents for introducing organic matter into the soil in tropical rain forests; this matter becomes the nucleus for a host of other organisms, including nematodes and arthropods, after it is discarded by the ants. One ant species cultures a yeast; all others grow a mycelium. In the higher species the mycelium forms clusters of inflated hyphae. Mycologists accept as valid two names for confirmed fruiting stages: Leucocoprinus ( or

  8. Functional Imaging of Human Vestibular Cortex Activity Elicited by Skull Tap and Auditory Tone Burst

    NASA Technical Reports Server (NTRS)

    Noohi, Fatemeh; Kinnaird, Catherine; Wood, Scott; Bloomberg, Jacob; Mulavara, Ajitkumar; Seidler, Rachael

    2014-01-01

    The aim of the current study was to characterize the brain activation in response to two modes of vestibular stimulation: skull tap and auditory tone burst. The auditory tone burst has been used in previous studies to elicit saccular Vestibular Evoked Myogenic Potentials (VEMP) (Colebatch & Halmagyi 1992; Colebatch et al. 1994). Some researchers have reported that airconducted skull tap elicits both saccular and utricle VEMPs, while being faster and less irritating for the subjects (Curthoys et al. 2009, Wackym et al., 2012). However, it is not clear whether the skull tap and auditory tone burst elicit the same pattern of cortical activity. Both forms of stimulation target the otolith response, which provides a measurement of vestibular function independent from semicircular canals. This is of high importance for studying the vestibular disorders related to otolith deficits. Previous imaging studies have documented activity in the anterior and posterior insula, superior temporal gyrus, inferior parietal lobule, pre and post central gyri, inferior frontal gyrus, and the anterior cingulate cortex in response to different modes of vestibular stimulation (Bottini et al., 1994; Dieterich et al., 2003; Emri et al., 2003; Schlindwein et al., 2008; Janzen et al., 2008). Here we hypothesized that the skull tap elicits the similar pattern of cortical activity as the auditory tone burst. Subjects put on a set of MR compatible skull tappers and headphones inside the 3T GE scanner, while lying in supine position, with eyes closed. All subjects received both forms of the stimulation, however, the order of stimulation with auditory tone burst and air-conducted skull tap was counterbalanced across subjects. Pneumatically powered skull tappers were placed bilaterally on the cheekbones. The vibration of the cheekbone was transmitted to the vestibular cortex, resulting in vestibular response (Halmagyi et al., 1995). Auditory tone bursts were also delivered for comparison. To validate

  9. Methodology to determine skull bone and brain responses from ballistic helmet-to-head contact loading using experiments and finite element analysis.

    PubMed

    Pintar, Frank A; Philippens, Mat M G M; Zhang, JiangYue; Yoganandan, Narayan

    2013-11-01

    The objective of the study was to obtain helmet-to-head contact forces from experiments, use a human head finite element model to determine regional responses, and compare outputs to skull fracture and brain injury thresholds. Tests were conducted using two types of helmets (A and B) fitted to a head-form. Seven load cells were used on the head-form back face to measure helmet-to-head contact forces. Projectiles were fired in frontal, left, right, and rear directions. Three tests were conducted with each helmet in each direction. Individual and summated force- and impulse-histories were obtained. Force-histories were inputted to the human head-helmet finite element model. Pulse durations were approximately 4 ms. One-third force and impulse were from the central load cell. 0.2% strain and 40 MPa stress limits were not exceeded for helmet-A. For helmet-B, strains exceeded in left, right, and rear; pressures exceeded in bilateral directions; volume of elements exceeding 0.2% strains correlated with the central load cell forces. For helmet-A, volumes exceeding brain pressure threshold were: 5-93%. All elements crossed the pressure limit for helmet-B. For both helmets, no brain elements exceeded peak principal strain limit. These findings advance our understanding of skull and brain biomechanics from helmet-head contact forces.

  10. Methodology to determine skull bone and brain responses from ballistic helmet-to-head contact loading using experiments and finite element analysis.

    PubMed

    Pintar, Frank A; Philippens, Mat M G M; Zhang, JiangYue; Yoganandan, Narayan

    2013-11-01

    The objective of the study was to obtain helmet-to-head contact forces from experiments, use a human head finite element model to determine regional responses, and compare outputs to skull fracture and brain injury thresholds. Tests were conducted using two types of helmets (A and B) fitted to a head-form. Seven load cells were used on the head-form back face to measure helmet-to-head contact forces. Projectiles were fired in frontal, left, right, and rear directions. Three tests were conducted with each helmet in each direction. Individual and summated force- and impulse-histories were obtained. Force-histories were inputted to the human head-helmet finite element model. Pulse durations were approximately 4 ms. One-third force and impulse were from the central load cell. 0.2% strain and 40 MPa stress limits were not exceeded for helmet-A. For helmet-B, strains exceeded in left, right, and rear; pressures exceeded in bilateral directions; volume of elements exceeding 0.2% strains correlated with the central load cell forces. For helmet-A, volumes exceeding brain pressure threshold were: 5-93%. All elements crossed the pressure limit for helmet-B. For both helmets, no brain elements exceeded peak principal strain limit. These findings advance our understanding of skull and brain biomechanics from helmet-head contact forces. PMID:23791942

  11. Gamma titanium aluminide production using the Induction Skull Melting (ISM) process

    SciTech Connect

    Reed, S.

    1995-12-31

    Since 1985, more than 2,000 titanium aluminide heats have been produced using the Induction Skull Melting (ISM) process. The history of ISM/Gamma production will be discussed in this paper. Gamma titanium aluminide processing with Induction Skull Melting offers many advantages over other types of reactive alloy melting methods. These advantages will be discussed as well as drawbacks. Also, potential markets and applications for ISM/Gamma will be presented.

  12. Scalp and skull influence on near infrared photon propagation in the Colin27 brain template.

    PubMed

    Strangman, Gary E; Zhang, Quan; Li, Zhi

    2014-01-15

    Near-infrared neuromonitoring (NIN) is based on near-infrared spectroscopy (NIRS) measurements performed through the intact scalp and skull. Despite the important effects of overlying tissue layers on the measurement of brain hemodynamics, the influence of scalp and skull on NIN sensitivity are not well characterized. Using 3555 Monte Carlo simulations, we estimated the sensitivity of individual continuous-wave NIRS measurements to brain activity over the entire adult human head by introducing a small absorption perturbation to brain gray matter and quantifying the influence of scalp and skull thickness on this sensitivity. After segmenting the Colin27 template into five tissue types (scalp, skull, cerebrospinal fluid, gray matter and white matter), the average scalp thickness was 6.9 ± 3.6 mm (range: 3.6-11.2mm), while the average skull thickness was 6.0 ± 1.9 mm (range: 2.5-10.5mm). Mean NIN sensitivity - defined as the partial path length through gray matter divided by the total photon path length - ranged from 0.06 (i.e., 6% of total path length) at a 20mm source-detector separation, to over 0.19 at 50mm separations. NIN sensitivity varied substantially around the head, with occipital pole exhibiting the highest NIRS sensitivity to gray matter, whereas inferior frontal regions had the lowest sensitivity. Increased scalp and skull thickness were strongly associated with decreased sensitivity to brain tissue. Scalp thickness always exhibited a slightly larger effect on sensitivity than skull thickness, but the effect of both varied with SD separation. We quantitatively characterize sensitivity around the head as well as the effects of scalp and skull, which can be used to interpret NIN brain activation studies as well as guide the design, development and optimization of NIRS devices and sensors.

  13. Ontogenetic change in skull morphology and mechanical advantage in the spotted hyena (Crocuta crocuta).

    PubMed

    Tanner, Jaime B; Zelditch, Miriam L; Lundrigan, Barbara L; Holekamp, Kay E

    2010-03-01

    Weaning represents a challenging transition for young mammals, one particularly difficult for species coping with extreme conditions during feeding. Spotted hyenas (Crocuta crocuta) experience such extreme conditions imposed by intense feeding competition during which the ability to consume large quantities of food quickly is highly advantageous. As adult spotted hyenas have massive skulls specialized for durophagy and can feed very rapidly, young individuals are likely at a competitive disadvantage until that specialized morphology is completely developed. Here we document developmental changes in skull size, shape, and mechanical advantage of the jaws. Sampling an ontogenetic series of Crocuta skulls from individuals ranging in age from 2 months to 18 years, we use linear measurements and geometric morphometrics to test hypotheses suggesting that size, limited mechanical advantage of the jaws, and/or limited attachment sites for jaw muscles might constrain the feeding performance of juveniles. We also examine skull development in relation to key life history events, including weaning and reproductive maturity, to inquire whether ontogeny of the feeding apparatus is slower or more protracted in this species than in carnivores not specialized for durophagy. We find that, although mechanical advantage reaches maturity in hyenas at 22 months, adult skull size is not achieved until 29 months of age, and skull shape does not reach maturity until 35 months. The latter is nearly 2 years after mean weaning age, and more than 1 year after reproductive maturity. Thus, skull development in Crocuta is indeed protracted relative to that in most other carnivores. Based on the skull features that continue to change and to provide additional muscle attachment area, protracted development may be largely due to development of the massive musculature required by durophagy. These findings may ultimately shed light on the adaptive significance of the unusual "role-reversed" pattern of

  14. Ontogenetic change in skull morphology and mechanical advantage in the spotted hyena (Crocuta crocuta).

    PubMed

    Tanner, Jaime B; Zelditch, Miriam L; Lundrigan, Barbara L; Holekamp, Kay E

    2010-03-01

    Weaning represents a challenging transition for young mammals, one particularly difficult for species coping with extreme conditions during feeding. Spotted hyenas (Crocuta crocuta) experience such extreme conditions imposed by intense feeding competition during which the ability to consume large quantities of food quickly is highly advantageous. As adult spotted hyenas have massive skulls specialized for durophagy and can feed very rapidly, young individuals are likely at a competitive disadvantage until that specialized morphology is completely developed. Here we document developmental changes in skull size, shape, and mechanical advantage of the jaws. Sampling an ontogenetic series of Crocuta skulls from individuals ranging in age from 2 months to 18 years, we use linear measurements and geometric morphometrics to test hypotheses suggesting that size, limited mechanical advantage of the jaws, and/or limited attachment sites for jaw muscles might constrain the feeding performance of juveniles. We also examine skull development in relation to key life history events, including weaning and reproductive maturity, to inquire whether ontogeny of the feeding apparatus is slower or more protracted in this species than in carnivores not specialized for durophagy. We find that, although mechanical advantage reaches maturity in hyenas at 22 months, adult skull size is not achieved until 29 months of age, and skull shape does not reach maturity until 35 months. The latter is nearly 2 years after mean weaning age, and more than 1 year after reproductive maturity. Thus, skull development in Crocuta is indeed protracted relative to that in most other carnivores. Based on the skull features that continue to change and to provide additional muscle attachment area, protracted development may be largely due to development of the massive musculature required by durophagy. These findings may ultimately shed light on the adaptive significance of the unusual "role-reversed" pattern of

  15. Resolution of "salt and pepper" appearance of the skull with vitamin D therapy.

    PubMed

    Kaur, Gursimran; Singh, Parminder; Mittal, Naveen; Singla, Mani Kant

    2013-10-01

    Chronic hypovitaminosis D leads to state of decreased mineralization and generalized osteomalacia. It also results in secondary hyperparathyroidism causing increased bone turn over and decreased bone mass, manifested radiologically as a "salt and pepper" appearance in skull, subperiosteal resorption, bone cysts and lytic lesions. In this case, a young male patient with hypovitaminosis D and secondary hyperparathyroidism, radiological features show resolution of "salt and pepper" appearance of the skull with vitamin D in 11 months and regression of other lytic lesions.

  16. Sinonasal Malignancies of Anterior Skull Base: Histology-driven Treatment Strategies.

    PubMed

    Castelnuovo, Paolo; Turri-Zanoni, Mario; Battaglia, Paolo; Antognoni, Paolo; Bossi, Paolo; Locatelli, Davide

    2016-02-01

    The advances in endoscopy have revolutionized the management of sinonasal and skull base lesions. Many complex cancers that traditionally required open approaches are now amenable to purely endoscopic endonasal resection, providing less invasive surgery with lower morbidity but with comparable oncologic outcomes in terms of survival rates. This article discusses the current evidence for the multimodal management of sinonasal and anterior skull base cancers focusing on the different treatment protocols driven by histologic subtypes.

  17. Effect of the Rat Skull On Focused US, as Measured by MR Thermometry

    NASA Astrophysics Data System (ADS)

    King, Randy; Rieke, Viola; Pauly, Kim Butts

    2010-03-01

    MR-guided therapeutic ultrasound is becoming increasingly prominent among a range of brain treatments from localized tumors and pain alleviation to neurostimulation. To investigate the influence of the skull on the acoustic field, an appropriate animal model must be established and so the effect of the rat skull needs to be considered and possibly compensated for, when using it as a model to perform therapeutic ultrasound in the brain. Temperature monitoring of both in-vivo and ex vivo experiments was performed in a 3T MRI (GE Signa, Milwaukee WS) using the PRF method. Sonications were performed with a 2D PZT array comprised of 1024 elements at 0.55 MHz. Intensities were kept low enough to limit temperature rise in the brain to about 10° C. Temperature maps were acquired 2-3 mm from the inner surface of the skull in phantom material, which was placed behind the skull. Three ex-vivo skulls were used. A grid pattern covering the entire skull was laid out for sonications. Only 11/48 sonications created a small single spot showing temperature rise in phantom material. In all other sonications the heat was very diffuse with multiple focal spots. This is compared to the phantom with no skull were 2/41 sonications did not create a small single spots of temperature rise, and in those two spots edge effects can be contributed to the unfocused pattern. All other sonications, performed at the same depth of sonication as in the skull, created an individual thermal spot, which was on average within 0.5 mm in any direction from the expected location.

  18. Pediatric anterior skull base tumors: Our experience and review of literature

    PubMed Central

    Venkataramana, N. K.; Anantheswar, Y. N.

    2010-01-01

    Surgery for skull base lesions has advanced considerably in the past few years. The improvement in surgical results could be attributed to the availability of refined imaging modalities, modern technological advances and multidisciplinary team approach. In this report, we present our personal experience in the surgical management of 45 children with a variety of skull base lesions treated over 10 years. This article includes a retrospective analysis of the surgical approaches used and their results with a review of the literature. PMID:21042498

  19. Dental fillings in Civil War skulls: what do they tell us?

    PubMed

    Glenner, R A; Willey, P; Sledzik, P S; Junger, E P

    1996-11-01

    This article discusses the dental techniques, methods and materials used in the South during the Civil War based on the dental restorations found in the skulls of four confederate soldiers. The skulls display a variety of dental filling materials, including thorium, lead, tin and tin amalgam. These materials were used at a time when more valuable materials, such as gold and silver, were not readily available in the South. PMID:8952248

  20. Quality-of-Life after Anterior Skull Base Surgery: A Systematic Review.

    PubMed

    Kirkman, Matthew A; Borg, Anouk; Al-Mousa, Alaa; Haliasos, Nikolaos; Choi, David

    2014-04-01

    Background Improved treatment and survival of patients with skull base tumors has made the assessment of quality-of-life (QoL) in this population increasingly important. This article provides a comprehensive systematic review pertaining to QoL assessment in adults undergoing anterior skull base surgery. Methods We performed a literature search using the electronic databases of Ovid Medline and Embase. Additional articles were identified through a search using the phrase anterior skull base. Further articles were sought through hand-searching relevant journals and reference lists of identified articles. Results Our search strategy identified 29 articles for inclusion in our systematic review, with considerable variation between studies in population characteristics, methodological design and quality, follow-up length, and outcome assessment. The most commonly used QoL tools were the Karnofsky Performance Status and the Anterior Skull Base Questionnaire. QoL following anterior skull base surgery appears to improve beyond preoperative levels in the months after surgery. For patients undergoing endoscopic skull base surgery, the gain in QoL appears to be greater and may manifest earlier, with no clear long-term deleterious effect on sinonasal outcomes compared with open surgery. Conclusions QoL after anterior skull base surgery in adults appears to improve within several months of surgery, but earlier and to a larger extent if the endoscopic approach is used. Given the relative paucity and heterogeneity of anterior skull base tumors, large-scale prospective multicentre studies utilizing valid and reliable multidimensional QoL tools are required. This may result in improved patient care, by understanding patients' needs better and facilitating the provision of reliable outcome data for clinical trials.

  1. Quality-of-Life after Anterior Skull Base Surgery: A Systematic Review.

    PubMed

    Kirkman, Matthew A; Borg, Anouk; Al-Mousa, Alaa; Haliasos, Nikolaos; Choi, David

    2014-04-01

    Background Improved treatment and survival of patients with skull base tumors has made the assessment of quality-of-life (QoL) in this population increasingly important. This article provides a comprehensive systematic review pertaining to QoL assessment in adults undergoing anterior skull base surgery. Methods We performed a literature search using the electronic databases of Ovid Medline and Embase. Additional articles were identified through a search using the phrase anterior skull base. Further articles were sought through hand-searching relevant journals and reference lists of identified articles. Results Our search strategy identified 29 articles for inclusion in our systematic review, with considerable variation between studies in population characteristics, methodological design and quality, follow-up length, and outcome assessment. The most commonly used QoL tools were the Karnofsky Performance Status and the Anterior Skull Base Questionnaire. QoL following anterior skull base surgery appears to improve beyond preoperative levels in the months after surgery. For patients undergoing endoscopic skull base surgery, the gain in QoL appears to be greater and may manifest earlier, with no clear long-term deleterious effect on sinonasal outcomes compared with open surgery. Conclusions QoL after anterior skull base surgery in adults appears to improve within several months of surgery, but earlier and to a larger extent if the endoscopic approach is used. Given the relative paucity and heterogeneity of anterior skull base tumors, large-scale prospective multicentre studies utilizing valid and reliable multidimensional QoL tools are required. This may result in improved patient care, by understanding patients' needs better and facilitating the provision of reliable outcome data for clinical trials. PMID:24719794

  2. Growing for different ends.

    PubMed

    Catts, Oron; Zurr, Ionat

    2014-11-01

    Tissue engineering and regenerative biology are usually discussed in relation to biomedical research and applications. However, hand in hand with developments of this field in the biomedical context, other approaches and uses for non-medical ends have been explored. There is a growing interest in exploring spin off tissue engineering and regenerative biology technologies in areas such as consumer products, art and design. This paper outlines developments regarding in vitro meat and leather, actuators and bio-mechanic interfaces, speculative design and contemporary artistic practices. The authors draw on their extensive experience of using tissue engineering for non-medical ends to speculate about what lead to these applications and their possible future development and uses. Avoiding utopian and dystopian postures and using the notion of the contestable, this paper also mentions some philosophical and ethical consideration stemming from the use of non-medical approaches to tissue constructs. This article is part of a directed issue entitled: Regenerative Medicine: the challenge of translation.

  3. Growing for different ends.

    PubMed

    Catts, Oron; Zurr, Ionat

    2014-11-01

    Tissue engineering and regenerative biology are usually discussed in relation to biomedical research and applications. However, hand in hand with developments of this field in the biomedical context, other approaches and uses for non-medical ends have been explored. There is a growing interest in exploring spin off tissue engineering and regenerative biology technologies in areas such as consumer products, art and design. This paper outlines developments regarding in vitro meat and leather, actuators and bio-mechanic interfaces, speculative design and contemporary artistic practices. The authors draw on their extensive experience of using tissue engineering for non-medical ends to speculate about what lead to these applications and their possible future development and uses. Avoiding utopian and dystopian postures and using the notion of the contestable, this paper also mentions some philosophical and ethical consideration stemming from the use of non-medical approaches to tissue constructs. This article is part of a directed issue entitled: Regenerative Medicine: the challenge of translation. PMID:25286303

  4. A statistical skull geometry model for children 0-3 years old.

    PubMed

    Li, Zhigang; Park, Byoung-Keon; Liu, Weiguo; Zhang, Jinhuan; Reed, Matthew P; Rupp, Jonathan D; Hoff, Carrie N; Hu, Jingwen

    2015-01-01

    Head injury is the leading cause of fatality and long-term disability for children. Pediatric heads change rapidly in both size and shape during growth, especially for children under 3 years old (YO). To accurately assess the head injury risks for children, it is necessary to understand the geometry of the pediatric head and how morphologic features influence injury causation within the 0-3 YO population. In this study, head CT scans from fifty-six 0-3 YO children were used to develop a statistical model of pediatric skull geometry. Geometric features important for injury prediction, including skull size and shape, skull thickness and suture width, along with their variations among the sample population, were quantified through a series of image and statistical analyses. The size and shape of the pediatric skull change significantly with age and head circumference. The skull thickness and suture width vary with age, head circumference and location, which will have important effects on skull stiffness and injury prediction. The statistical geometry model developed in this study can provide a geometrical basis for future development of child anthropomorphic test devices and pediatric head finite element models.

  5. Gender differences in D-aspartic acid content in skull bone.

    PubMed

    Torikoshi-Hatano, Aiko; Namera, Akira; Shiraishi, Hiroaki; Arima, Yousuke; Toubou, Hirokazu; Ezaki, Jiro; Morikawa, Masami; Nagao, Masataka

    2012-12-01

    In forensic medicine, the personal identification of cadavers is one of the most important tasks. One method of estimating age at death relies on the high correlation between racemization rates in teeth and actual age, and this method has been applied successfully in forensic odontology for several years. In this study, we attempt to facilitate the analysis of racemized amino acids and examine the determination of age at death on the basis of the extent of aspartic acid (Asp) racemization in skull bones. The specimens were obtained from 61 human skull bones (19 females and 42 males) that underwent judicial autopsy from October 2010 to May 2012. The amount of D-Asp and L-Asp, total protein, osteocalcin, and collagen I in the skull bones was measured. Logistic regression analysis was performed for age, sex, and each measured protein. The amount of D-Asp in the female skull bones was significantly different from that in the male skull bones (p = 0.021), whereas the amount of L-Asp was similar. Thus, our study indicates that the amount of D-Asp in skull bones is different between the sexes.

  6. Automatic sex determination of skulls based on a statistical shape model.

    PubMed

    Luo, Li; Wang, Mengyang; Tian, Yun; Duan, Fuqing; Wu, Zhongke; Zhou, Mingquan; Rozenholc, Yves

    2013-01-01

    Sex determination from skeletons is an important research subject in forensic medicine. Previous skeletal sex assessments are through subjective visual analysis by anthropologists or metric analysis of sexually dimorphic features. In this work, we present an automatic sex determination method for 3D digital skulls, in which a statistical shape model for skulls is constructed, which projects the high-dimensional skull data into a low-dimensional shape space, and Fisher discriminant analysis is used to classify skulls in the shape space. This method combines the advantages of metrical and morphological methods. It is easy to use without professional qualification and tedious manual measurement. With a group of Chinese skulls including 127 males and 81 females, we choose 92 males and 58 females to establish the discriminant model and validate the model with the other skulls. The correct rate is 95.7% and 91.4% for females and males, respectively. Leave-one-out test also shows that the method has a high accuracy.

  7. CraMs: Craniometric Analysis Application Using 3D Skull Models.

    PubMed

    Dias, Paulo; Neves, Luis; Santos, Daniel; Coelho, Catarina; Ferreira, Maria Teresa; Santos, Helder; Silva, Samuel; Santos, Beatriz Sousa

    2015-01-01

    Craniometric analysis plays an important role in anthropology studies and forensics. This paper presents CraMs, an application using a new craniometric approach based on 3D models of the skull. The main objective is to obtain, through a process supervised by anthropologists, the main points of interest used to compute craniometric measurements. The application aids this process by analyzing the skull geometry and automatically providing points of interest. The application also allows for semiautomatic point detection, where the user provides an initial guess that might be refined based on the curvature of the skull, as well as the manual selection of any other points of interest. Moreover, results comparing measurements obtained with CraMs and traditional craniometry methods on eight skulls suggest that the application provides comparable craniometric measurements and lower inter-observer variability. This approach offers advantages such as an easier access to skulls with no risk of bone damage and the possibility of defining new measurements based on morphology or other skull characteristics, which are not possible using traditional methods. PMID:26594956

  8. Developmental changes in the skull morphology of common minke whales Balaenoptera acutorostrata.

    PubMed

    Nakamura, Gen; Kato, Hidehiro

    2014-10-01

    We investigated growth-related and sex-related morphological changes in the skulls of 144 North Pacific common minke whales Balaenoptera acutorostrata. Measurement was conducted at 39 points on the skull and mandible to extract individual allometric equations relating the length and zygomatic width of the skull. The results revealed no significant differences in skull morphology by sex except for width of occipital bone. The size relative to the skull of the anatomical parts involved in feeding, such as the rostrum and mandible, increased after birth. In contrast, the sensory organs and the anatomical regions involved in neurological function, such as the orbit, tympanic bullae, and foramen magnum, were fully developed at birth, and their relative size reduced over the course of development. This is the first study to investigate developmental changes in the skull morphology using more than 100 baleen whale specimens, and we believe the results of this study will contribute greatly to multiple areas of baleen whale research, including taxonomy and paleontology.

  9. Allometric comparison of skulls from two closely related weasels, Mustela itatsi and M. sibirica.

    PubMed

    Suzuki, Satoshi; Abe, Mikiko; Motokawa, Masaharu

    2011-09-01

    We conducted an interspecific comparison of skulls from two closely related but differently sized mustelid species, Mustela itatsi and M. sibirica (Mammalia, Carnivora, Mustelidae); a sexual comparison within the latter species showed remarkable size dimorphism. We clarified several differences in skull proportion related to size using allometric analyses and qualitative comparisons. Allometric analysis revealed that the skulls of male M. itatsi (the smaller species) have a relatively long palate; a slender viscerocranium and postorbital constriction; a broad, short, and low neurocranium; small carnassials; and a short mandible with a thin body and small ramus compared to the skulls of male M. sibirica (the larger species). Similar results were obtained when male M. itatsi were compared to female M. sibirica, although the male M. itatsi had a broader viscerocranium than female M. sibirica. A sexual comparison in M. sibirica revealed a larger skull size among the males with a relatively wide viscerocranium; wide postorbital constriction; a slender, long, and high neurocranium; short and wide auditory bullae; short carnassials; and a long and high mandible compared to females. Qualitative comparisons revealed changes in a few characters depending on skull size or with respect to some cranial components in each species. The interspecific differences observed were clearly larger than the intraspecific differences for three qualitative characters. The allometric and qualitative differences detected between these species suggest that each species is not simply the dwarf and/or giant morph of the other, and complicated differences were clarified. PMID:21882957

  10. A statistical skull geometry model for children 0-3 years old.

    PubMed

    Li, Zhigang; Park, Byoung-Keon; Liu, Weiguo; Zhang, Jinhuan; Reed, Matthew P; Rupp, Jonathan D; Hoff, Carrie N; Hu, Jingwen

    2015-01-01

    Head injury is the leading cause of fatality and long-term disability for children. Pediatric heads change rapidly in both size and shape during growth, especially for children under 3 years old (YO). To accurately assess the head injury risks for children, it is necessary to understand the geometry of the pediatric head and how morphologic features influence injury causation within the 0-3 YO population. In this study, head CT scans from fifty-six 0-3 YO children were used to develop a statistical model of pediatric skull geometry. Geometric features important for injury prediction, including skull size and shape, skull thickness and suture width, along with their variations among the sample population, were quantified through a series of image and statistical analyses. The size and shape of the pediatric skull change significantly with age and head circumference. The skull thickness and suture width vary with age, head circumference and location, which will have important effects on skull stiffness and injury prediction. The statistical geometry model developed in this study can provide a geometrical basis for future development of child anthropomorphic test devices and pediatric head finite element models. PMID:25992998

  11. CraMs: Craniometric Analysis Application Using 3D Skull Models.

    PubMed

    Dias, Paulo; Neves, Luis; Santos, Daniel; Coelho, Catarina; Ferreira, Maria Teresa; Santos, Helder; Silva, Samuel; Santos, Beatriz Sousa

    2015-01-01

    Craniometric analysis plays an important role in anthropology studies and forensics. This paper presents CraMs, an application using a new craniometric approach based on 3D models of the skull. The main objective is to obtain, through a process supervised by anthropologists, the main points of interest used to compute craniometric measurements. The application aids this process by analyzing the skull geometry and automatically providing points of interest. The application also allows for semiautomatic point detection, where the user provides an initial guess that might be refined based on the curvature of the skull, as well as the manual selection of any other points of interest. Moreover, results comparing measurements obtained with CraMs and traditional craniometry methods on eight skulls suggest that the application provides comparable craniometric measurements and lower inter-observer variability. This approach offers advantages such as an easier access to skulls with no risk of bone damage and the possibility of defining new measurements based on morphology or other skull characteristics, which are not possible using traditional methods.

  12. Relationship of brain and skull in pre- and postoperative sagittal synostosis

    PubMed Central

    Aldridge, Kristina; Kane, Alex A; Marsh, Jeffrey L; Yan, Peng; Govier, Daniel; Richtsmeier, Joan T

    2005-01-01

    Models of vertebrate skull evolution stress the coordinated developmental relationship between the skull and the brain that it houses. This study investigates the relationship between altered skull morphology and brain morphology in premature fusion of the cranial sagittal suture (isolated sagittal synostosis; ISS), a condition associated with dysmorphology of both neurocranium and brain. Although the skull displays a more normal shape following reconstructive cranial vault surgery, effects of this surgery on the brain have not been investigated. Landmark coordinate data were collected from three-dimensional magnetic resonance imaging reconstructions of the brain in a sample of ISS patients and an age-matched unaffected cohort. These data were analysed using Euclidean distance matrix analysis (EDMA). Results show that the brain in ISS is dysmorphic preoperatively, displaying a posteriorly directed neural expansion that does not ‘worsen’ with growth. Postoperatively, the brain in ISS displays a more globular shape overall as compared with the preoperative morphology, but differs from normal in its subcortical morphology. These results show that the ISS brain is altered following neurocranial surgery, but does not more closely approximate that of unaffected individuals. This suggests that although the brain is affected by manipulation of the skull, it retains a growth pattern that is, at least in part, independent of the skull. PMID:15817105

  13. A Statistical Skull Geometry Model for Children 0-3 Years Old

    PubMed Central

    Li, Zhigang; Park, Byoung-Keon; Liu, Weiguo; Zhang, Jinhuan; Reed, Matthew P.; Rupp, Jonathan D.; Hoff, Carrie N.; Hu, Jingwen

    2015-01-01

    Head injury is the leading cause of fatality and long-term disability for children. Pediatric heads change rapidly in both size and shape during growth, especially for children under 3 years old (YO). To accurately assess the head injury risks for children, it is necessary to understand the geometry of the pediatric head and how morphologic features influence injury causation within the 0–3 YO population. In this study, head CT scans from fifty-six 0–3 YO children were used to develop a statistical model of pediatric skull geometry. Geometric features important for injury prediction, including skull size and shape, skull thickness and suture width, along with their variations among the sample population, were quantified through a series of image and statistical analyses. The size and shape of the pediatric skull change significantly with age and head circumference. The skull thickness and suture width vary with age, head circumference and location, which will have important effects on skull stiffness and injury prediction. The statistical geometry model developed in this study can provide a geometrical basis for future development of child anthropomorphic test devices and pediatric head finite element models. PMID:25992998

  14. A skull segmentation method for brain MR images based on multiscale bilateral filtering scheme

    NASA Astrophysics Data System (ADS)

    Yang, Xiaofeng; Fei, Baowei

    2010-03-01

    We present a novel automatic segmentation method for the skull on brain MR images for attenuation correction in combined PET/MRI applications. Our method transforms T1-weighted MR images to the Radon domain and then detects the feature of the skull. In the Radon domain we use a bilateral filter to construct a multiscale images series. For the repeated convolution we increase the spatial smoothing at each scale and make the cumulative width of the spatial and range Gaussian doubled at each scale. Two filters with different kernels along the vertical direction are applied along the scales from the coarse to fine levels. The results from a coarse scale give a mask for the next fine scale and supervise the segmentation in the next fine scale. The method is robust for noise MR images because of its multiscale bilateral filtering scheme. After combining the two filtered sinogram, the reciprocal binary sinogram of the skull is obtained for the reconstruction of the skull image. We use the filtered back projection method to reconstruct the segmented skull image. We define six metrics to evaluate our segmentation method. The method has been tested with brain phantom data, simulated brain data, and real MRI data. Evaluation results showed that our method is robust and accurate, which is useful for skull segmentation and subsequently for attenuation correction in combined PET/MRI applications.

  15. A Basal Lithostrotian Titanosaur (Dinosauria: Sauropoda) with a Complete Skull: Implications for the Evolution and Paleobiology of Titanosauria.

    PubMed

    Martínez, Rubén D F; Lamanna, Matthew C; Novas, Fernando E; Ridgely, Ryan C; Casal, Gabriel A; Martínez, Javier E; Vita, Javier R; Witmer, Lawrence M

    2016-01-01

    is missing for at least 13 million years of the Cretaceous. The skull anatomy of Sarmientosaurus suggests that multiple titanosaurian species with dissimilar cranial structures coexisted in the early Late Cretaceous of southern South America. Furthermore, the new taxon possesses a number of distinctive morphologies-such as the ossified cervical tendon, extremely pneumatized cervical vertebrae, and a habitually downward-facing snout-that have rarely, if ever, been documented in other titanosaurs, thus broadening our understanding of the anatomical diversity of this remarkable sauropod clade. The latter two features were convergently acquired by at least one penecontemporaneous diplodocoid, and may represent mutual specializations for consuming low-growing vegetation. PMID:27115989

  16. A Basal Lithostrotian Titanosaur (Dinosauria: Sauropoda) with a Complete Skull: Implications for the Evolution and Paleobiology of Titanosauria.

    PubMed

    Martínez, Rubén D F; Lamanna, Matthew C; Novas, Fernando E; Ridgely, Ryan C; Casal, Gabriel A; Martínez, Javier E; Vita, Javier R; Witmer, Lawrence M

    2016-01-01

    is missing for at least 13 million years of the Cretaceous. The skull anatomy of Sarmientosaurus suggests that multiple titanosaurian species with dissimilar cranial structures coexisted in the early Late Cretaceous of southern South America. Furthermore, the new taxon possesses a number of distinctive morphologies-such as the ossified cervical tendon, extremely pneumatized cervical vertebrae, and a habitually downward-facing snout-that have rarely, if ever, been documented in other titanosaurs, thus broadening our understanding of the anatomical diversity of this remarkable sauropod clade. The latter two features were convergently acquired by at least one penecontemporaneous diplodocoid, and may represent mutual specializations for consuming low-growing vegetation.

  17. A Basal Lithostrotian Titanosaur (Dinosauria: Sauropoda) with a Complete Skull: Implications for the Evolution and Paleobiology of Titanosauria

    PubMed Central

    Martínez, Rubén D. F.; Lamanna, Matthew C.; Novas, Fernando E.; Ridgely, Ryan C.; Casal, Gabriel A.; Martínez, Javier E.; Vita, Javier R.; Witmer, Lawrence M.

    2016-01-01

    history of which is missing for at least 13 million years of the Cretaceous. The skull anatomy of Sarmientosaurus suggests that multiple titanosaurian species with dissimilar cranial structures coexisted in the early Late Cretaceous of southern South America. Furthermore, the new taxon possesses a number of distinctive morphologies—such as the ossified cervical tendon, extremely pneumatized cervical vertebrae, and a habitually downward-facing snout—that have rarely, if ever, been documented in other titanosaurs, thus broadening our understanding of the anatomical diversity of this remarkable sauropod clade. The latter two features were convergently acquired by at least one penecontemporaneous diplodocoid, and may represent mutual specializations for consuming low-growing vegetation. PMID:27115989

  18. Superior osteogenesis in transplanted allogeneic canine skull following chemical sterilization

    SciTech Connect

    Prolo, D.J.; Pedrotti, P.W.; Burres, K.P.; Oklund, S.

    1982-08-01

    Sterilization of allogeneic bone increases the availability of this tissue for supplanting skeletal defects and effecting fusions. The optimal sterilant destroys micro-organisms, preserves the physical and chemical integrity of bone and possibly even reduces immunogenicity. Cortical bone of skull heals slowly and is variably resorbed. Of 36 dogs, spontaneous regeneration in 72 paired 20 mm defects was constant but always incomplete, and restored only about one third of the cross-sectional area of the defect at six months. The repair in defects replaced with canine allogeneic bony disc, sterilized with ethylene oxide (n . 9), gamma irradiation (n . 7), or methanol/chloroform/iodoacetic acid (n . 7) and then lyophilizedd, was compared with repair in defects filled with aseptically procured lyophilized only (n . 23) discs from the same donor. Criteria for evaluation of implants at six months included volume of defect filled, radiodensity, extent of fusion around circumference, revascularization, and remodeling. Bony discs sterilized with methanol/chloroform/iodoacetic acid remodeled at a superior rate (p less than 0.01). Radiation sterilization resulted in diminished density and inferentially reduced protection of the brain (p less than 0.025). Ethylene oxide, lyophilized implants, and implants lyophilized only produced comparable repair. Whereas an acceptable cranioplasty was achieved in 86% of methanol/chloroform/iodoacetic acid, lyophilize implants, all other alloimplants served an osteoconductive function with a successful repair occurring in 56% to 58%.

  19. Novel Application of Helical Tomotherapy in Whole Skull Palliative Radiotherapy

    SciTech Connect

    Rodrigues, George Yartsev, Slav; Coad, Terry; Bauman, Glenn

    2008-01-01

    Helical tomotherapy (HT) is a radiation planning/delivery platform that combines inversely planned IMRT with on-board megavoltage imaging. A unique HT radiotherapy whole skull brain sparing technique is described in a patient with metastatic prostate cancer. An inverse HT plan and an accompanying back-up conventional lateral 6-MV parallel opposed pair (POP) plan with corresponding isodose distributions and dose-volume histograms (DVH) were created and assessed prior to initiation of therapy. Plans conforming to the planning treatment volume (PTV) with significant sparing of brain, optic nerve, and eye were created. Dose heterogeneity to the PTV target was slightly higher in the HT plan compared to the back-up POP plan. Conformal sparing of brain, optic nerve, and eye was achieved by the HT plan. Similar lens and brain stem/spinal cord doses were seen with both plans. Prospective clinical evaluation with relevant end points (quality of life, symptom relief) are required to confirm the potential benefits of highly conformal therapies applied to palliative situations such as this case.

  20. Intercavernous Venous Communications in the Human Skull Base

    PubMed Central

    Aquini, Mauro Guidotti; Marrone, Antonio Carlos Huf; Schneider, Felipe Luis

    1994-01-01

    The intercavernous communications of the skull base were studied in 32 sphenoid blocks using electrolytic decalcification techniques, vascular filling, x-rays, and serial anatomical sections. In this study four intercavernous connections were found: anterior intercavernous sinus (AIS), posterior intercavernous sinus (PIS), inferior intercavernous sinus (IIS), and basilar plexus (BP). The AIS was present in 100% of the cases, with diameters ranging from 0.57 mm to 5.43 mm; in 17 cases (53.12%) it took up the whole anterior wall of the hypophyseal fossa. The PIS was also detected in 100% of the cases, and its diameters ranged from 0.71 mm to 4.14 mm. The IIS was identified in 31 cases (96.9%), assuming three different forms: plexuslike, venous lake, and mixed. The BP was found in 100% of the material analyzed; in 23 cases (71.9%) it proved to be the widest intercavernous communication. In 12 cases of this series the hypophysis was completely enveloped by venous structures, except at the level of the sellar diaphragm. ImagesFigure 1Figure 2Figure 3 PMID:17171164

  1. Phenotypic Covariation and Morphological Diversification in the Ruminant Skull.

    PubMed

    Haber, Annat

    2016-05-01

    Differences among clades in their diversification patterns result from a combination of extrinsic and intrinsic factors. In this study, I examined the role of intrinsic factors in the morphological diversification of ruminants, in general, and in the differences between bovids and cervids, in particular. Using skull morphology, which embodies many of the adaptations that distinguish bovids and cervids, I examined 132 of the 200 extant ruminant species. As a proxy for intrinsic constraints, I quantified different aspects of the phenotypic covariation structure within species and compared them with the among-species divergence patterns, using phylogenetic comparative methods. My results show that for most species, divergence is well aligned with their phenotypic covariance matrix and that those that are better aligned have diverged further away from their ancestor. Bovids have dispersed into a wider range of directions in morphospace than cervids, and their overall disparity is higher. This difference is best explained by the lower eccentricity of bovids' within-species covariance matrices. These results are consistent with the role of intrinsic constraints in determining amount, range, and direction of dispersion and demonstrate that intrinsic constraints can influence macroevolutionary patterns even as the covariance structure evolves. PMID:27104991

  2. Anatomically based modelling of the human skull and jaw.

    PubMed

    van Essen, N L; Anderson, I A; Hunter, P J; Carman, J; Clarke, R D; Pullan, A J

    2005-01-01

    We present here an anatomically based model of the human masticatory system that provides a framework for simulating the complex chewing process. The initial motivation for creating this model was the desire to have a computational model of the human jaw that can be used to simulate the action of simple bites, and to calculate the stresses and forces on the teeth that are involved. The model created also provides a platform that can be used to investigate other features of the masticatory system. To construct this global model, individual models of the bones of the skull and jaw were created from generic data sets. Geometric models of the muscles of mastication were also created and attached to the appropriate bones. To complete this initial model, representations of the crowns of the teeth were created and a basic model of the temporomandibular joint (TMJ) was included. The finite element method was used to solve for the stresses and strains created by the loading conditions during a clenching simulation involving the mandible bone. The model presented here is also discussed in relation to a model of the entire musculo-skeletal system being developed as part of the Physiome Project.

  3. Quality of life following endonasal skull base surgery.

    PubMed

    Pant, Harshita; Bhatki, Amol M; Snyderman, Carl H; Vescan, Allan D; Carrau, Ricardo L; Gardner, Paul; Prevedello, Daniel; Kassam, Amin B

    2010-01-01

    The importance of quality of life (QOL) outcomes following treatments for head and neck tumors are now increasingly appreciated and measured to improve medical and surgical care for these patients. An understanding of the definitions in the setting of health care and the use of appropriate QOL instruments and measures are critical to obtain meaningful information that guides decision making in various aspects of patient health care. QOL outcomes following cranial base surgery is only recently being defined. In this article, we describe the current published data on QOL outcomes following cranial base surgery and provide preliminary prospective data on QOL outcomes and sinonasal morbidity in patients who underwent endonasal cranial base surgery for management of various skull base tumors at our institution. We used a disease-specific multidimensional instrument to measure QOL outcomes in these patients. Our results show that although sinonasal morbidity is increased, this is temporary, and the vast majority of patients have a very good QOL by 4 to 6 months after endonasal approach to the cranial base. PMID:20592856

  4. Nasal fracture (image)

    MedlinePlus

    A nasal fracture is a break in the bone over the ridge of the nose. It usually results from a blunt ... and is one of the most common facial fracture. Symptoms of a broken nose include pain, blood ...

  5. Metatarsal stress fractures - aftercare

    MedlinePlus

    The metatarsal bones are the long bones in your foot that connect your ankle to your toes. A stress fracture is a break in the bone that happens with repeated injury or stress. Stress fractures are caused ...

  6. Fractures in anisotropic media

    NASA Astrophysics Data System (ADS)

    Shao, Siyi

    Rocks may be composed of layers and contain fracture sets that cause the hydraulic, mechanical and seismic properties of a rock to be anisotropic. Coexisting fractures and layers in rock give rise to competing mechanisms of anisotropy. For example: (1) at low fracture stiffness, apparent shear-wave anisotropy induced by matrix layering can be masked or enhanced by the presence of a fracture, depending on the fracture orientation with respect to layering, and (2) compressional-wave guided modes generated by parallel fractures can also mask the presence of matrix layerings for particular fracture orientations and fracture specific stiffness. This report focuses on two anisotropic sources that are widely encountered in rock engineering: fractures (mechanical discontinuity) and matrix layering (impedance discontinuity), by investigating: (1) matrix property characterization, i.e., to determine elastic constants in anisotropic solids, (2) interface wave behavior in single-fractured anisotropic media, (3) compressional wave guided modes in parallel-fractured anisotropic media (single fracture orientation) and (4) the elastic response of orthogonal fracture networks. Elastic constants of a medium are required to understand and quantify wave propagation in anisotropic media but are affected by fractures and matrix properties. Experimental observations and analytical analysis demonstrate that behaviors of both fracture interface waves and compressional-wave guided modes for fractures in anisotropic media, are affected by fracture specific stiffness (controlled by external stresses), signal frequency and relative orientation between layerings in the matrix and fractures. A fractured layered medium exhibits: (1) fracture-dominated anisotropy when the fractures are weakly coupled; (2) isotropic behavior when fractures delay waves that are usually fast in a layered medium; and (3) matrix-dominated anisotropy when the fractures are closed and no longer delay the signal. The

  7. Displaced patella fractures.

    PubMed

    Della Rocca, Gregory J

    2013-10-01

    Displaced patella fractures often result in disruption of the extensor mechanism of the knee. An intact extensor mechanism is a requirement for unassisted gait. Therefore, operative treatment of the displaced patella fracture is generally recommended. The evaluation of the patella fracture patient includes examination of extensor mechanism integrity. Operative management of patella fractures normally includes open reduction with internal fixation, although partial patellectomy is occasionally performed, with advancement of quadriceps tendon or patellar ligament to the fracture bed. Open reduction with internal fixation has historically been performed utilizing anterior tension band wiring, although comminution of the fracture occasionally makes this fixation construct inadequate. Supplementation or replacement of the tension band wire construct with interfragmentary screws, cerclage wire or suture, and/or plate-and-screw constructs may add to the stability of the fixation construct. Arthrosis of the patellofemoral joint is very common after healing of patella fractures, and substantial functional deficits may persist long after fracture healing has occurred.

  8. An MR-compatible phantom for evaluating the propagation of high intensity focused ultrasound through the skull

    NASA Astrophysics Data System (ADS)

    Hadjisavvas, V.; Mylonas, N.; Ioannides, K.; Damianou, C.

    2012-10-01

    BACKGROUND: In this paper an MR-compatible phantom for evaluating the propagation of high intensity focused ultrasound through the skull is presented. METHODS: The phantom was constructed using the thermoplastic material of ABS. The attenuation of ABS was measured using the transmission-reception method. Knowing the attenuation of human skull, the thickness of the phantom was chosen appropriately so as to achieve the same attenuation effect as in the case of human skull. The phantom was designed using CAD software and then manufactured in a rapid prototyping machine. In order to test the phantom a single element spherically focused transducer of 5 cm diameter, focusing at 10 cm and operating at either 0.5 MHz or 1 MHz was used. Brain tissue was mimicked either using gel phantoms or freshly excised tissue. RESULTS: The measured temperature due to an ultrasonic exposure with the presence of skull and without the skull was measured. It was found that the propagation of ultrasound through the skull was much better with the 0.5 MHz transducer. The skull phantom was tested also inside an MRI scanner, and we were able to detect temperature using the MRI technique of FSPGR indicating that with low frequency ultrasound propagation through the skull is possible. CONCLUSIONS: The skull phantom is a very successful tool for evaluating the propagation of ultrasound during the presence of skull.

  9. How Do Galaxies Grow?

    NASA Astrophysics Data System (ADS)

    2008-08-01

    Astronomers have caught multiple massive galaxies in the act of merging about 4 billion years ago. This discovery, made possible by combining the power of the best ground- and space-based telescopes, uniquely supports the favoured theory of how galaxies form. ESO PR Photo 24/08 ESO PR Photo 24/08 Merging Galaxies in Groups How do galaxies form? The most widely accepted answer to this fundamental question is the model of 'hierarchical formation', a step-wise process in which small galaxies merge to build larger ones. One can think of the galaxies forming in a similar way to how streams merge to form rivers, and how these rivers, in turn, merge to form an even larger river. This theoretical model predicts that massive galaxies grow through many merging events in their lifetime. But when did their cosmological growth spurts finish? When did the most massive galaxies get most of their mass? To answer these questions, astronomers study massive galaxies in clusters, the cosmological equivalent of cities filled with galaxies. "Whether the brightest galaxies in clusters grew substantially in the last few billion years is intensely debated. Our observations show that in this time, these galaxies have increased their mass by 50%," says Kim-Vy Tran from the University of Zürich, Switzerland, who led the research. The astronomers made use of a large ensemble of telescopes and instruments, including ESO's Very Large Telescope (VLT) and the Hubble Space Telescope, to study in great detail galaxies located 4 billion light-years away. These galaxies lie in an extraordinary system made of four galaxy groups that will assemble into a cluster. In particular, the team took images with VIMOS and spectra with FORS2, both instruments on the VLT. From these and other observations, the astronomers could identify a total of 198 galaxies belonging to these four groups. The brightest galaxies in each group contain between 100 and 1000 billion of stars, a property that makes them comparable

  10. Hydraulic fracture design optimization

    SciTech Connect

    Lee, Tae-Soo; Advani, S.H.

    1992-01-01

    This research and development investigation, sponsored by US DOE and the oil and gas industry, extends previously developed hydraulic fracture geometry models and applied energy related characteristic time concepts towards the optimal design and control of hydraulic fracture geometries. The primary objective of this program is to develop rational criteria, by examining the associated energy rate components during the hydraulic fracture evolution, for the formulation of stimulation treatment design along with real-time fracture configuration interpretation and control.

  11. Hydraulic fracture design optimization

    SciTech Connect

    Lee, Tae-Soo; Advani, S.H.

    1992-06-01

    This research and development investigation, sponsored by US DOE and the oil and gas industry, extends previously developed hydraulic fracture geometry models and applied energy related characteristic time concepts towards the optimal design and control of hydraulic fracture geometries. The primary objective of this program is to develop rational criteria, by examining the associated energy rate components during the hydraulic fracture evolution, for the formulation of stimulation treatment design along with real-time fracture configuration interpretation and control.

  12. Clavicle fractures: individualizing treatment for fracture type.

    PubMed

    Housner, Jeffrey A; Kuhn, John E

    2003-12-01

    Clavicle fractures are common injuries in both children and adults. In most cases, the diagnosis can be made readily from the patient's history and physical examination. X-rays are helpful to confirm the diagnosis, to assess the severity of the fracture, and to follow interval healing. Most fractures are treated nonoperatively, and surgical intervention is typically reserved for unstable distal clavicle fractures. Nonoperative options involve either a sling-and-swathe or figure-of-eight splint. Return-to-play decisions should be individualized based on the age of the patient, location and severity of the fracture, degree of clinical and radiographic healing, and the sport in which the athlete will be participating.

  13. Growing Galaxies Gently

    NASA Astrophysics Data System (ADS)

    2010-10-01

    New observations from ESO's Very Large Telescope have, for the first time, provided direct evidence that young galaxies can grow by sucking in the cool gas around them and using it as fuel for the formation of many new stars. In the first few billion years after the Big Bang the mass of a typical galaxy increased dramatically and understanding why this happened is one of the hottest problems in modern astrophysics. The results appear in the 14 October issue of the journal Nature. The first galaxies formed well before the Universe was one billion years old and were much smaller than the giant systems - including the Milky Way - that we see today. So somehow the average galaxy size has increased as the Universe has evolved. Galaxies often collide and then merge to form larger systems and this process is certainly an important growth mechanism. However, an additional, gentler way has been proposed. A European team of astronomers has used ESO's Very Large Telescope to test this very different idea - that young galaxies can also grow by sucking in cool streams of the hydrogen and helium gas that filled the early Universe and forming new stars from this primitive material. Just as a commercial company can expand either by merging with other companies, or by hiring more staff, young galaxies could perhaps also grow in two different ways - by merging with other galaxies or by accreting material. The team leader, Giovanni Cresci (Osservatorio Astrofisico di Arcetri) says: "The new results from the VLT are the first direct evidence that the accretion of pristine gas really happened and was enough to fuel vigorous star formation and the growth of massive galaxies in the young Universe." The discovery will have a major impact on our understanding of the evolution of the Universe from the Big Bang to the present day. Theories of galaxy formation and evolution may have to be re-written. The group began by selecting three very distant galaxies to see if they could find evidence

  14. Non-invasive examination of a skull fragment recovered from a World War Two aircraft crash site.

    PubMed

    Gapert, René; Rieder, Kurt

    2013-09-01

    The discovery of human remains dating to the time of the Second World War is a common occurrence in Europe and the Pacific regions. This case report demonstrates the analysis of a bone fragment recovered from a Luftwaffe crash site in Austria during the summer of 2007. Eye-witness statements and official reports were used to reconstruct the historical background of the case. A recovered German military identity tag helped to identify the pilot. Aircraft parts, also discovered at the crash site in 2007, aided the identification of the aircraft type and corroborated the eye-witness reports of the final moments before and during the crash. The bone was analyzed chiefly to establish its human or non-human origin and to identify from which anatomic region the fragment could have arisen. It was identified as part of a human adult skull which exhibited peri-mortem fractures and heat damage as well as post-mortem vegetation staining. The historical background information in connection with the morphological analysis led to the presumptive identification of the cranial fragment as belonging to a downed German pilot.

  15. Variations in leopard cat (Prionailurus bengalensis) skull morphology and body size: sexual and geographic influences.

    PubMed

    Sicuro, Fernando L; Oliveira, Luiz Flamarion B

    2015-01-01

    The leopard cat, Prionailurus bengalensis (Kerr, 1792), is one of the most widespread Asian cats, occurring in continental eastern and southeastern Asia. Since 1929, several studies have focused on the morphology, ecology, and taxonomy of leopard cats. Nevertheless, hitherto there has been no agreement on basic aspects of leopard cat biology, such as the presence or absence of sexual dimorphism, morphological skull and body differences between the eleven recognized subspecies, and the biogeography of the different morphotypes. Twenty measurements on 25 adult leopard cat skulls from different Asian localities were analyzed through univariate and multivariate statistical approaches. Skull and external body measurements from studies over the last 77 years were assembled and organized in two categories: full data and summary data. Most of this database comprises small samples, which have never been statistically tested and compared with each other. Full data sets were tested with univariate and multivariate statistical analyses; summary data sets (i.e., means, SDs, and ranges) were analyzed through suitable univariate approaches. The independent analyses of the data from these works confirmed our original results and improved the overview of sexual dimorphism and geographical morphological variation among subspecies. Continental leopard cats have larger skulls and body dimensions. Skulls of Indochinese morphotypes have broader and higher features than those of continental morphotypes, while individuals from the Sunda Islands have skulls with comparatively narrow and low profiles. Cranial sexual dimorphism is present in different degrees among subspecies. Most display subtle sex-related variations in a few skull features. However, in some cases, sexual dimorphism in skull morphology is absent, such as in P. b. sumatranus and P. b. borneoensis. External body measurement comparisons also indicate the low degree of sexual dimorphism. Apart from the gonads, the longer hind

  16. Phylogenetic and environmental components of morphological variation: skull, mandible, and molar shape in marmots (Marmota, Rodentia).

    PubMed

    Caumul, Radhekshmi; Polly, P David

    2005-11-01

    The phenotype is a product of its phylogenetic history and its recent adaptation to local environments, but the relative importance of the two factors is controversial. We assessed the effects of diet, habitat, elevation, temperature, precipitation, body size, and mtDNA genetic divergence on shape variation in skulls, mandibles, and molars, structures that differ in their genetic and functional control. We asked whether these structures have adapted to environment to the same extent and whether they retain the same amount of phylogenetic signal. We studied these traits in intra- and interspecific populations of Eurasian marmots whose last common ancestor lived 2-5 million years ago. Path Analysis revealed that body size explained 10% of variation in skulls, 7% in mandibles, and 15% in molars. Local vegetation explained 7% of variation in skulls, 11% in mandibles, and 12% in molars. Dietary category explained 25% of variation in skulls, 11% in mandibles, and 9% in molars. Cyt b mtDNA divergence (phylogeny) explained 15% of variation in skulls, 7% in mandibles, and 5% in molars. Despite the percentages of phylogenetic variance, maximum-likelihood trees based on molar and skull shape recovered most phylogenetic groupings correctly, but mandible shape did not. The good performance of molars and skulls was probably due to different factors. Skulls are genetically and functionally more complicated than teeth, and they had more mathematically independent components of variation (5-6-in skulls compared to 3-in molars). The high proportion of diet-related variance was not enough to mask the phylogenetic signal. Molars had fewer independent components, but they also have less ecophenotypic variation and evolve more slowly, giving each component a proportionally stronger phylogenetic signal. Molars require larger samples for each operational taxonomic unit than the other structures because the proportion of within-taxon to between-taxon variation was higher. Good phylogenetic

  17. Variations in leopard cat (Prionailurus bengalensis) skull morphology and body size: sexual and geographic influences

    PubMed Central

    Oliveira, Luiz Flamarion B.

    2015-01-01

    The leopard cat, Prionailurus bengalensis (Kerr, 1792), is one of the most widespread Asian cats, occurring in continental eastern and southeastern Asia. Since 1929, several studies have focused on the morphology, ecology, and taxonomy of leopard cats. Nevertheless, hitherto there has been no agreement on basic aspects of leopard cat biology, such as the presence or absence of sexual dimorphism, morphological skull and body differences between the eleven recognized subspecies, and the biogeography of the different morphotypes. Twenty measurements on 25 adult leopard cat skulls from different Asian localities were analyzed through univariate and multivariate statistical approaches. Skull and external body measurements from studies over the last 77 years were assembled and organized in two categories: full data and summary data. Most of this database comprises small samples, which have never been statistically tested and compared with each other. Full data sets were tested with univariate and multivariate statistical analyses; summary data sets (i.e., means, SDs, and ranges) were analyzed through suitable univariate approaches. The independent analyses of the data from these works confirmed our original results and improved the overview of sexual dimorphism and geographical morphological variation among subspecies. Continental leopard cats have larger skulls and body dimensions. Skulls of Indochinese morphotypes have broader and higher features than those of continental morphotypes, while individuals from the Sunda Islands have skulls with comparatively narrow and low profiles. Cranial sexual dimorphism is present in different degrees among subspecies. Most display subtle sex-related variations in a few skull features. However, in some cases, sexual dimorphism in skull morphology is absent, such as in P. b. sumatranus and P. b. borneoensis. External body measurement comparisons also indicate the low degree of sexual dimorphism. Apart from the gonads, the longer hind

  18. Variations in leopard cat (Prionailurus bengalensis) skull morphology and body size: sexual and geographic influences.

    PubMed

    Sicuro, Fernando L; Oliveira, Luiz Flamarion B

    2015-01-01

    The leopard cat, Prionailurus bengalensis (Kerr, 1792), is one of the most widespread Asian cats, occurring in continental eastern and southeastern Asia. Since 1929, several studies have focused on the morphology, ecology, and taxonomy of leopard cats. Nevertheless, hitherto there has been no agreement on basic aspects of leopard cat biology, such as the presence or absence of sexual dimorphism, morphological skull and body differences between the eleven recognized subspecies, and the biogeography of the different morphotypes. Twenty measurements on 25 adult leopard cat skulls from different Asian localities were analyzed through univariate and multivariate statistical approaches. Skull and external body measurements from studies over the last 77 years were assembled and organized in two categories: full data and summary data. Most of this database comprises small samples, which have never been statistically tested and compared with each other. Full data sets were tested with univariate and multivariate statistical analyses; summary data sets (i.e., means, SDs, and ranges) were analyzed through suitable univariate approaches. The independent analyses of the data from these works confirmed our original results and improved the overview of sexual dimorphism and geographical morphological variation among subspecies. Continental leopard cats have larger skulls and body dimensions. Skulls of Indochinese morphotypes have broader and higher features than those of continental morphotypes, while individuals from the Sunda Islands have skulls with comparatively narrow and low profiles. Cranial sexual dimorphism is present in different degrees among subspecies. Most display subtle sex-related variations in a few skull features. However, in some cases, sexual dimorphism in skull morphology is absent, such as in P. b. sumatranus and P. b. borneoensis. External body measurement comparisons also indicate the low degree of sexual dimorphism. Apart from the gonads, the longer hind

  19. Bending fracture in carbon nanotubes.

    PubMed

    Kuo, Wen-Shyong; Lu, Hsin-Fang

    2008-12-10

    A novel approach was adopted to incur bending fracture in carbon nanotubes (CNTs). Expanded graphite (EG) was made by intercalating and exfoliating natural graphite flakes. The EG was deposited with nickel particles, from which CNTs were grown by chemical vapor deposition. The CNTs were tip-grown, and their roots were fixed on the EG flakes. The EG flakes were compressed, and many CNTs on the surface were fragmented due to the compression-induced bending. Two major modes of the bending fracture were observed: cone-shaped and shear-cut. High-resolution scanning electron microscopy (SEM) and transmission electron microscopy (TEM) were used to examine the crack growth within the graphene layers. The bending fracture is characterized by two-region crack growth. An opening crack first appears around the outer-tube due to the bending-induced tensile stress. The crack then branches to grow along an inclined direction toward the inner-tube due to the presence of the shear stress in between graphene layers. An inner-tube pullout with inclined side surface is formed. The onset and development of the crack in these two regions are discussed. PMID:21730690

  20. Osteoporotic vertebral fractures redux.

    PubMed

    Lentle, B C; Gordon, P; Ward, L

    2008-02-01

    Osteoporosis remains an important cause of morbidity and mortality especially in the elderly. This fact is largely due to fractures of the proximal femur and spine. As recently recognized, vertebral fractures are as much a threat to health and longevity as fractures of the proximal femur. In recent decades, the development of tools to evaluate fracture risk as well as medications to treat osteoporosis has altered the management of people who are at fracture risk. At the same time identification and management procedures concerning spinal fracturing are not very clear. Besides there is not even clear consensus about what exactly constitutes a vertebral fracture, particularly those of minor degree. While height loss is a simple and valuable tool to detect vertebral fractures, it is neither sensitive nor specific enough to replace radiographs. Some 65% of fractures cause no symptoms. Often vertebral fractures are misdiagnosed, especially if they have occurred silently and if the opportunity for diagnosis arises fortuitously. It is to the patient's benefit that radiologists report and physicians identify vertebral fractures evident on a chest or other radiograph, no matter how incidental to the immediate clinical indication for the examination. Technological evolution now allows dual-energy x-ray absorptiometry machines to be used to take spine images while doing a densitometry. The images are adequate, even if not of high radiographic quality, and, more important, the patient undergoes a smaller radiation dose than with conventional spinal radiographs. Such technology may promote fracture recognition. The recognition of vertebral fractures, as well as the prevention and treatment of further fractures, will likely do much to reduce both the burden of osteoporosis-related morbidity and mortality, as well as fracture-related costs to healthcare systems.