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Sample records for growing skull fracture

  1. Skull fracture

    MedlinePlus

    Basilar skull fracture; Depressed skull fracture; Linear skull fracture ... Skull fractures may occur with head injuries . The skull provides good protection for the brain. However, a severe impact ...

  2. 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

  3. 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

  4. 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 ...

  5. 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

  6. An accessory skull suture mimicking a skull fracture.

    PubMed

    Wiedijk, J E F; Soerdjbalie-Maikoe, V; Maat, G J R; Maes, A; van Rijn, R R; de Boer, H H

    2016-03-01

    This paper describes an investigation of the sudden and unexpected death of a five-and-a-half-month-old boy. As in every Dutch case of sudden unexpected death in infancy (SUDI), a multidisciplinary diagnostic approach was used. This included post-mortem radiography, showing a linear discontinuity of the parietal bone. Originally this was interpreted as a skull fracture, but autopsy indicated no signs of mechanical trauma. Instead the defect was defined as a unilateral accessory suture of the parietal bone. The initial erroneous diagnosis had severe adverse consequences and thus every health care professional or forensic specialist dealing with paediatric mechanical traumas should be cautious of this rare anomaly. PMID:26860068

  7. A New Biomechanically-Based Criterion for Lateral Skull Fracture

    PubMed Central

    Vorst, Michael Vander; Chan, Philemon; Zhang, Jiangyue; Yoganandan, Narayan; Pintar, Frank

    2004-01-01

    This work develops a skull fracture criterion for lateral impact-induced head injury using postmortem human subject tests, anatomical test device measurements, statistical analyses, and finite element modeling. It is shown that skull fracture correlates with the tensile strain in the compact tables of the cranial bone as calculated by the finite element model and that the Skull Fracture Correlate (SFC), the average acceleration over the HIC time interval, is the best predictor of skull fracture. For 15% or less probability of skull fracture the lateral skull fracture criterion is SFC < 120 g, which is the same as the frontal criterion derived earlier. The biomechanical basis of SFC is established by its correlation with strain. PMID:15319125

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

    PubMed Central

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

    2013-01-01

    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

  9. 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

  10. [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

  11. [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

  12. The Comprehensive AOCMF Classification: Skull Base and Cranial Vault Fractures – Level 2 and 3 Tutorial

    PubMed Central

    Ieva, Antonio Di; Audigé, Laurent; Kellman, Robert M.; Shumrick, Kevin A.; Ringl, Helmut; Prein, Joachim; Matula, Christian

    2014-01-01

    The AOCMF Classification Group developed a hierarchical three-level craniomaxillofacial classification system with increasing level of complexity and details. The highest level 1 system distinguish four major anatomical units, including the mandible (code 91), midface (code 92), skull base (code 93), and cranial vault (code 94). This tutorial presents the level 2 and more detailed level 3 systems for the skull base and cranial vault units. The level 2 system describes fracture location outlining the topographic boundaries of the anatomic regions, considering in particular the endocranial and exocranial skull base surfaces. The endocranial skull base is divided into nine regions; a central skull base adjoining a left and right side are divided into the anterior, middle, and posterior skull base. The exocranial skull base surface and cranial vault are divided in regions defined by the names of the bones involved: frontal, parietal, temporal, sphenoid, and occipital bones. The level 3 system allows assessing fracture morphology described by the presence of fracture fragmentation, displacement, and bone loss. A documentation of associated intracranial diagnostic features is proposed. This tutorial is organized in a sequence of sections dealing with the description of the classification system with illustrations of the topographical skull base and cranial vault regions along with rules for fracture location and coding, a series of case examples with clinical imaging and a general discussion on the design of this classification. PMID:25489394

  13. [Skull base fractures in childhood. The role of CT in the accuracy of diagnosis].

    PubMed

    Sült, T P; Szever, Z; Mona, T; Kerényi, I; Harmat, G

    1999-03-28

    The authors treated 51 patients suffering from basilar skull fractures between January 1995 and June 1997 following a newly initiated protocol. The effectiveness of recognizing these fractures increased to twice and a half after applying a complex (neurologic, otolaryngologic, ophthalmologic, X-ray and cranial CT) diagnostic examination. CT scans were performed at the slightest suspicion of basilar skull fracture since they provide far more information than the native skull X-ray. A close coherence was observed concerning clinical symptoms, potential complications and the manifested fractures, which helped to draw an exact therapeutical strategy and to prevent potential complications. The authors found X-ray gave satisfactory information only about fractures starting on the vault. In the studied period CT proved the basilar skull fracture in 40 (78%) cases out of the total 51. X-ray did it in only 4 (8%) cases and raised the suspicion of the vault fracture spreading to the cranial floor in 20 (39%) cases. CT did not prove the clinically supposed basilar skull fractures in only 11 (22%) cases compared to 27 (53%) by X-ray. After having consultation with radiologists examination methods were always determined by the clinical picture and the available technical conditions (helical technique, multiplan or 3D-reconstruction). PMID:10349317

  14. 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

  15. 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. PMID:26703363

  16. A 5-year study of the outcome of surgically treated depressed skull fractures.

    PubMed Central

    Al-Haddad, Syed A.; Kirollos, Ramez

    2002-01-01

    BACKGROUND: Many changes and improvement have taken place in the management of head injured patients in the last 20 years. There have been few recent studies analysing the overall outcomes including early complications of depressed skull fractures. The aim of our study was, therefore, to examine the factors influencing the surgical outcome of patients with depressed skull fractures. METHODS: We reviewed case notes of 73 consecutive surgically treated depressed skull fractures during the period from 1 January 1994 to 31 December 1998 admitted to the Walton Centre for Neurology and Neurosurgery, Liverpool. RESULTS: There was a male preponderance of 9:1. Alleged assault was the most common cause of depressed skull fractures followed by road traffic accidents. Postoperative infection rate was 8.2%. More than 80% of patients received prophylactic antibiotics. We failed to show any statistically significant association between the use of antibiotics and reduction of the rate of infection. However, prevalence of infection was significantly associated with brain contusion, low GCS score and dural tear (P < 0.05). Prevalence of early post-traumatic epilepsy was 12.3%. No patients received prophylactic anticonvulsants. There was no significant association between dural tear and prevalence of post-traumatic epilepsy. Mortality rate was 1.4%. CONCLUSIONS: Paediatric populations have better outcome; 7 out of 10 patients in this series progressed to full recovery. Use of prophylactic antibiotics did not reduce the infection rate. Presence of dural tear was not associated with an increase risk of post-traumatic epilepsy. PMID:12092875

  17. 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…

  18. 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, ...

  19. Radiolucent hair accessories causing depressed skull fracture following blunt cranial trauma.

    PubMed

    Syed, Omar N; Hankinson, Todd C; Mack, William J; Feldstein, Neil A; Anderson, Richard C E

    2008-12-01

    Pediatric neurosurgeons frequently care for children with traumatic scalp and skull injury. Foreign objects are often observed on imaging and may influence the clinician's decision-making process. The authors report on 2 cases of poorly visualized hair beads that had become embedded into the skull during blunt trauma. In both cases, skull radiography and CT scanning demonstrated depressed, comminuted fractures with poorly demonstrated spherical radiolucencies in the overlying scalp. The nature of these objects was initially unclear, and they could have represented air that entered the scalp during trauma. In one case, scalp inspection demonstrated no evidence of the bead. In the other case, a second bead was observed at the site of scalp laceration. In both cases, the beads were surgically removed, the fractures were elevated, and the patients recovered uneventfully. Radiolucent fashion accessories, such as hair beads, may be difficult to appreciate on clinical examination and may masquerade as clinically insignificant air following cranial trauma. If they are not removed, these foreign bodies may pose the risk of an infection. Pediatric neurosurgeons should consider hair accessories in the differential diagnosis of foreign bodies that may produce skull fracture following blunt trauma. PMID:19035690

  20. 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

  1. Penetrating skull fracture by a wooden object: Management dilemmas and literature review.

    PubMed

    Arifin, Muhammad Zafrullah; Gill, Arwinder Singh; Faried, Ahmad

    2012-07-01

    Most penetrating skull injuries are caused by gun shot wounds or missiles. The compound depressed skull fracture represents an acute neurosurgical emergency. Management and diagnosis of such cases have been described, but its occurence following a fall onto a piece of wood is quite unusual. A 75-year-old female fell onto a piece of wood that penetrated her skull on the left frontal region and was treated in our department. The patient had no neurological deficits during presentation. She was managed surgically and removal of the wooden object was performed to prevent early or late infection complications. Wooden foreign bodies often pose a different set of challenges as far as penetrating injuries to the brain are concerned. Radiological difficulties and increased rates of infection due to its porous nature make these types of injuries particularly interesting. Their early diagnosis and appropriate treatment can minimize the risk of complications. PMID:23293668

  2. 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. PMID:19291431

  3. Posttraumatic Intracranial Tuberculous Subdural Empyema in a Patient with Skull Fracture

    PubMed Central

    Kim, Jiha; Kim, Choonghyo; Ryu, Young-Joon

    2016-01-01

    Intracranial tuberculous subdural empyema (ITSE) is extremely rare. To our knowledge, only four cases of microbiologically confirmed ITSE have been reported in the English literature to date. Most cases have arisen in patients with pulmonary tuberculosis regardless of trauma. A 46-year-old man presented to the emergency department after a fall. On arrival, he complained of pain in his head, face, chest and left arm. He was alert and oriented. An initial neurological examination was normal. Radiologic evaluation revealed multiple fractures of his skull, ribs, left scapula and radius. Though he had suffered extensive skull fractures of his cranium, maxilla, zygoma and orbital wall, the sustained cerebral contusion and hemorrhage were mild. Eighteen days later, he suddenly experienced a general tonic-clonic seizure. Radiologic evaluation revealed a subdural empyema in the left occipital area that was not present on admission. We performed a craniotomy, and the empyema was completely removed. Microbiological examination identified Mycobacterium tuberculosis (M. tuberculosis). After eighteen months of anti-tuberculous treatment, the empyema disappeared completely. This case demonstrates that tuberculosis can induce empyema in patients with skull fractures. Thus, we recommend that M. tuberculosis should be considered as the probable pathogen in cases with posttraumatic empyema. PMID:27226867

  4. Posttraumatic Intracranial Tuberculous Subdural Empyema in a Patient with Skull Fracture.

    PubMed

    Kim, Jiha; Kim, Choonghyo; Ryu, Young-Joon; Lee, Seung Jin

    2016-05-01

    Intracranial tuberculous subdural empyema (ITSE) is extremely rare. To our knowledge, only four cases of microbiologically confirmed ITSE have been reported in the English literature to date. Most cases have arisen in patients with pulmonary tuberculosis regardless of trauma. A 46-year-old man presented to the emergency department after a fall. On arrival, he complained of pain in his head, face, chest and left arm. He was alert and oriented. An initial neurological examination was normal. Radiologic evaluation revealed multiple fractures of his skull, ribs, left scapula and radius. Though he had suffered extensive skull fractures of his cranium, maxilla, zygoma and orbital wall, the sustained cerebral contusion and hemorrhage were mild. Eighteen days later, he suddenly experienced a general tonic-clonic seizure. Radiologic evaluation revealed a subdural empyema in the left occipital area that was not present on admission. We performed a craniotomy, and the empyema was completely removed. Microbiological examination identified Mycobacterium tuberculosis (M. tuberculosis). After eighteen months of anti-tuberculous treatment, the empyema disappeared completely. This case demonstrates that tuberculosis can induce empyema in patients with skull fractures. Thus, we recommend that M. tuberculosis should be considered as the probable pathogen in cases with posttraumatic empyema. PMID:27226867

  5. 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. PMID:24644219

  6. [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

  7. Skull fracture during infancy: a five-year follow-up.

    PubMed

    Marsh, Nigel V; Whitehead, Gabrielle

    2005-04-01

    A group of 19 children, who had received a skull fracture during infancy, were assessed at least 5 years following injury. The majority of the group (89%) had received a mild traumatic brain injury (TBI), with the remaining two (11%) having a moderate injury. The neuropsychological, academic, and psychosocial functioning of the TBI group was compared to that of 20 orthopedic subjects. The two groups were matched on the variables of gender, age, and socio-economic status. The TBI group was impaired on tests of visual attention and memory for faces. The two groups did not differ significantly on measures of language, sensorimotor functions, or visuospatial functioning. There were no statistically significant differences between the two groups on academic performance, or parent and teacher reports of psychosocial functioning. It is concluded that while there is an absence of deficits in the vast majority of functions, skull fracture in infancy can result in enduring impairment in specific cognitive skills related to the processing of complex nonverbal stimuli. PMID:15969357

  8. Multiple congenital skull fractures as a presentation of Ehlers-Danlos syndrome type VIIC.

    PubMed

    Bar-Yosef, Omer; Polak-Charcon, Sylvie; Hoffman, Chen; Feldman, Zeev P; Frydman, Moshe; Kuint, Jacob

    2008-12-01

    We describe a newborn infant with multiple congenital skull fractures and intracranial hemorrhage. He also had multiple skin folds suggesting a connective tissue abnormality. Electron microscopy of the skin biopsy showed collagen abnormalities with a "hieroglyphic appearance." The analysis of the synthesis of collagen in the cultured dermal fibroblasts demonstrated an accumulation of procollagen I. Molecular analysis found a nonsense mutation Q225X in ADAMTS2 gene, which encodes procollagen I N-terminal proteinase. All these findings confirmed the diagnosis of Ehlers-Danlos syndrome type VIIC (MIM 225410). Family studies suggested a founder effect in Ashkenazi Jews originating from Belarus. Prenatal diagnosis in the subsequent pregnancy reassured the parents that the fetus was an unaffected carrier. PMID:18973246

  9. 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

  10. 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. PMID:25900622

  11. 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. PMID:24853982

  12. 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

  13. Conservative treatment of isolated condylar fractures in growing patients.

    PubMed

    Chatzistavrou, Evangelia K; Basdra, Efthimia K

    2007-01-01

    Traumas to the mandible in children, due to falls or traffic accidents, can involve fractures in the condylar area. Without timely and proper diagnosis, such fractures may give rise to serious problems, such as growth disturbances of the face and disorders of the temporomandibular joint. Orthodontists are often involved in the diagnosis of condylar fractures but, more importantly, they should be involved in the successful conservative management of the fracture. The aim of this article is to present 5 cases of isolated condylar fractures in children (2 boys, 3 girls; age range 4.5 to 10 years) who were diagnosed and treated solely by a conservative orthopedic approach, involving the use of a functional appliance (activator). After a follow-up period of 1 year, clinical and radiologic examination indicated, due to the growth potential of the condyles during childhood, successful healing and remodeling had occurred in all 5 cases and no discomfort or complications were reported. A conservative treatment approach for an isolated condylar fracture, using a functional appliance during the growth period, can lead to complete restoration of the fractured area and re-establishment of physiologic function of the stomatognathic system with no signs of disturbance in dentofacial development. PMID:17902329

  14. An autopsy case of a decomposed body with keyhole gunshot wound and secondary skull fractures.

    PubMed

    Harada, Kazuki; Kuroda, Ryohei; Nakajima, Makoto; Takizawa, Ayako; Yoshida, Ken-ichi

    2012-09-01

    The decomposed body of a 53 or 57-year-old male was found with a gun in a locked car parked in a coin-operated parking lot. During autopsy, the entrance wound in the frontal bone showed a characteristic keyhole defect with internal and external beveling. There was no exit wound. The fragmented bullet traveled downward within the calvarium and struck the right orbital plate. Two independent linear fractures were observed away from the entrance. These were believed to be secondary fractures resulting neither from internal ricochet of the bullet nor from direct blunt force to the head. Although decomposition complicated the evaluation of the gunshot wound characteristics, microscopic examination confirmed large quantities of soot along the wound tract, supporting our conclusion that the range of fire was contact. PMID:22633563

  15. Early Surgery Does Not Seem to Be a Pivotal Criterion to Improve Prognosis in Patients with Frontal Depressed Skull Fractures

    PubMed Central

    2014-01-01

    Introduction. There has been much debate about the ideal timing of surgery of frontal depressed skull fractures (DSF). In this paper, we assess whether timing of surgery may have influenced outcome. Methods. Retrospective cohort of 40 consecutive patients with frontal DSF who underwent surgical treatment over a 36-month period. The patients were divided into early surgery group (ESG) which were operated within 24 h and delayed surgery group (DSG). Results. The population comprised 39 (97.50%) men and the mean age was 27.9 years (range, 2–81 yr). There was no difference of age (P = 0.53), gender male (P = 1.00), presence of focal lesion on head CT (P = 0.89), hypotension (P = 0.28), and hypoxia (P = 0.15). Mean Glasgow Coma Scale (GCS) was significantly lower in patients of ESG than DSG (8.75 and 11.7, resp., P = 0.02). There was no difference between the groups in relation to death (P = 0.13), unfavourable outcome (P = 0.41), late posttraumatic epilepsy (P = 0.64), and smell-and-taste disturbances (P = 1.00). Only one patient (3.5%) evolved meningitis during follow-up. Conclusion. We found no difference between the ESG and DSG in respect to death, unfavourable outcome, LPE, and STD. PMID:25197666

  16. 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 ...

  17. 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)

  18. 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.

  19. Hair Today; Scalped Tomorrow: Massive Subgaleal Haematoma Following Sudden Hair Pulling in an Adolescent in the Absence of Haematological Abnormality or Skull Fracture.

    PubMed

    Edmondson, Sarah-Jayne; Ramman, Saif; Hachach-Haram, Nadine; Bisarya, Kamal; Fu, Brian; Ong, Juling; Akhavani, Mo

    2016-07-01

    Subgaleal haematoma (SH) is a rare condition, most frequently observed in neonates as a complication of Ventouse-assisted delivery. There have been few patients reported beyond this period. Those that are present within the literature have typically resulted from significant blunt scalp trauma, with or without associated skull fracture. Those resulting secondary to relatively minor trauma, such as hair braiding or hair pulling, are rare but have been reported and are often associated with underlying haematological abnormalities or nonaccidental injury patients. Most patients resolve spontaneously and without complication. The authors report a rare patient of a delayed presentation of a massive SH in an adolescent following a seemingly innocuous episode of hair pulling whilst play-fighting, in the absence of any underlying haematological or anatomical abnormality. Due to the size of the SH and the appearance of large areas of calcification within the haematoma, early liaison with senior neuroradiologists and haematologists, to rule out underlying anatomical and haematological abnormalities, respectively, was essential to guide appropriate management. Our patient highlights the need for an awareness of the possible aetiologies of SH and the necessity of early active multidisciplinary team involvement in the management of such patients, which is critical to ensure optimum patient outcomes. PMID:27258718

  20. 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 ...

  1. 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

  2. Identification and characterization of growing large-scale en-echelon fractures in a salt mine

    NASA Astrophysics Data System (ADS)

    Maghsoudi, Samira; Hainzl, Sebastian; Cesca, Simone; Dahm, Torsten; Kaiser, Diethelm

    2014-02-01

    The spatiotemporal seismicity of acoustic emission (AE) events recorded in the Morsleben salt mine is investigated. Almost a year after backfilling of the cavities from 2003, microevents are distributed with distinctive stripe shapes above cavities at different depth levels. The physical forces driving the creation of these stripes are still unknown. This study aims to find the active stripes and track fracture developments over time by combining two different temporal and spatial clustering techniques into a single methodological approach. Anomalous seismicity parameters values like sharp b-value changes for two active stripes are good indicators to explain possible stress accumulation at the stripe tips. We identify the formation of two new seismicity stripes and show that the AE activities in active clusters are migrated mostly unidirectional to eastward and upward. This indicates that the growth of underlying macrofractures is controlled by the gradient of extensional stress. Studying size distribution characteristic in terms of frequency-magnitude distribution and b-value in active phase and phase with constant seismicity rate show that deviations from the Gutenberg-Richter power law can be explained by the inclusion of different activity phases: (1) the inactive period before the formation of macrofractures, which is characterized by a deficit of larger events (higher b-values) and (2) the period of fracture growth characterized by the occurrence of larger events (smaller b-values).

  3. [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

  4. 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. PMID:26614826

  5. 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. PMID:21107177

  6. 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

  7. 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.

  8. 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 ...

  9. Fractures

    MedlinePlus

    A fracture is a break, usually in a bone. If the broken bone punctures the skin, it is called an open ... falls, or sports injuries. Other causes are low bone density and osteoporosis, which cause weakening of the ...

  10. Ganglioneuroblastoma of Skull Base

    PubMed Central

    Ramaswamy, Balakrishnan; Menon, Shalini S.; Agarwal, Ashish Chandra; Nair, Suraj S.

    2015-01-01

    Neuroblastic tumours are common in childhood and adrenal glands are the most common site. Head and neck ganglioneuroblastomas are extremely rare and nose is a very uncommon site for a ganglioneuroblastoma. The management of this primitive sympathogonic tumour may vary depending on the age of the patient and stage of the tumour. We present a middle-aged man with a ganglioneuroblastoma of skull base, management of this tumour and a review of literature. PMID:26435974

  11. 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. PMID:24763233

  12. 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

  13. [The skull of Combe Capelle].

    PubMed

    Hoffmann, Almut; Wegner, Dietrich

    2002-12-01

    Since the end of World War II two of the most important anthropological artefacts of the Museum für Vor- und Frühgeschichte in Berlin, the skulls and skeletons of Le Moustier and Combe Capelle, were believed to be missing or destroyed, respectively. The postcrania were severely damaged during a fire after the museum was bombed in February 1945, while the skulls were brought to the Soviet Union in 1945. In 1965, the skull of the Neanderthal man from Le Moustier and the chain of the grave of Combe Capelle were found amongst the art objects returned by the Soviet Union into the German Democratic Republic in 1958. However, the Combe Capelle skull was still missing. In the end of 2001 this skull could be found and identified in a store-house of the museum. Now, one the oldest known representatives of Homo sapiens sapiens is again available for scientific research and public exhibitions. PMID:12529957

  14. 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 ...

  15. 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

  16. 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...

  17. 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...

  18. 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...

  19. 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...

  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. 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. PMID:27330416

  2. 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

  3. 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

  4. Mastoid emissary in Indian skulls.

    PubMed

    Piasecki, K; Wysocki, J

    1998-01-01

    Two hundred and eleven Indian skulls originating from medieval times, South of Peru, were studied in respect to variability of the mastoid emissary. Occurrence and localisation of the external orifice of the mastoid emissary were studied in three distinct and well-separated populations, living in the three different places: Villa el Salvador, Tablada de Lurin and Paracas. Most of the skulls presented considerable degree of artificial deformation. External orifice of the mastoid emissary was multiple in most of the skulls, especially in Villa el Salvador and Paracas populations. Mastoid emissaries in Indian were situated generally higher than in European, especially regarding the Paracas population. Significant sex differences were present in this material, regarded as a whole (summarized results for the three populations), what is in agreement with previous observations on European skulls. It indicates that even in cases of relatively deep deformation, some characteristic features of sex dimorphism of the human skull are noticeable. Additionally, the three studied populations, which were well separated from each other and lived alone, differed significantly regarding localization of the mastoid emissaries. PMID:9857576

  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. 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

  7. Landmark measurement of human skull

    NASA Astrophysics Data System (ADS)

    Zhai, Yu Jia; Ouyang, Jianfei; Cao, Xiaochun

    2010-06-01

    The landmark measurement of human skull is fundamental to geometric morphometry of palaeoanthropology. The landmarks are geometry points which can describe anatomically the homology of species group. They play an important role in palaeoanthropology. A structured-light based method is used to measure and make the 3D digital model of skull. The distances between all pairs of landmarks and interior angles from triangulations of the landmarks can be measured fast and accurately by the digital model. Other important geometric parameters of the skull, such as curvature, surface area, volume can also be measured. In order to validate and certificate the proposed method, 9 standard balls, which are embed at the landmarks, are measured by using Coordinate Measuring Arm (CMA). The experiment shows that the measuring errors of the distances and angles are less than 0.08 mm and 5' respectively.

  8. Skull base approaches in neurosurgery

    PubMed Central

    2010-01-01

    The skull base surgery is one of the most demanding surgeries. There are different structures that can be injured easily, by operating in the skull base. It is very important for the neurosurgeon to choose the right approach in order to reach the lesion without harming the other intact structures. Due to the pioneering work of Cushing, Hirsch, Yasargil, Krause, Dandy and other dedicated neurosurgeons, it is possible to address the tumor and other lesions in the anterior, the mid-line and the posterior cranial base. With the transsphenoidal, the frontolateral, the pterional and the lateral suboccipital approach nearly every region of the skull base is exposable. In the current state many different skull base approaches are described for various neurosurgical diseases during the last 20 years. The selection of an approach may differ from country to country, e.g., in the United States orbitozygomaticotomy for special lesions of the anterior skull base or petrosectomy for clivus meningiomas, are found more frequently than in Europe. The reason for writing the review was the question: Are there keyhole approaches with which someone can deal with a vast variety of lesions in the neurosurgical field? In my opinion the different surgical approaches mentioned above cover almost 95% of all skull base tumors and lesions. In the following text these approaches will be described. These approaches are: 1) pterional approach 2) frontolateral approach 3) transsphenoidal approach 4) suboccipital lateral approach These approaches can be extended and combined with each other. In the following we want to enhance this philosophy. PMID:20602753

  9. 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

  10. [Early stage of a cloverleaf skull malformation].

    PubMed

    Fischer, G; Hori, A; Ulbrich, R; Rath, W

    1982-12-01

    Cloverleaf skull anomaly was diagnosed sonographically and in the fetogram, together with concomitant chondrodystrophy. This resulted in an indication for intentional abortion in the 29th week. Consequently, this rare form of skull monstrosity could be examined pathologico-anatomically for the first time in a very early stage of foetal development. Contrary to the widely held opinion that the reason for such hideous malformation is a hydrocephalus internus due to a deformation of the skull base, we found a practically negligible hydrocephalus, although the cloverleaf skull had already developed in a very marked manner. Hence, this case contradicts the generally adopted formal pathogenetic interpretation of cloverleaf skull monstrosity. PMID:7178767

  11. 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

  12. 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

  13. Chondrosarcoma of the Skull Base

    PubMed Central

    Morimoto, Tadashi; Sasaki, Tomio; Takakura, Kintomo; Ishida, Tsuyoshi

    1992-01-01

    Five patients with chondrosarcoma, grade I or II, and one with mesenchymal chondrosarcoma of the skull base were treated at our clinic between 1967 and 1991. The patients were three men and three women who ranged in age from 21 to 39 years. The presenting symptoms were diplopia, decreased visual acuity, or symptoms of involvement of VIIIth and lower cranial nerves. The duration of the symptoms ranged from 18 months to 14 years. A plain skull x-ray and tomography of the skull, computed tomographic (CT) scans, and magnetic resonance images (MRI) revealed a calcified mass. Angiograms showed an occlusion of the arteries or venous sinuses, or both, in four patients, and a distinct tumor stain in one. The tumors were subtotally removed in all six cases. Two patients received postoperative irradiation for the residual tumor. In one patient, extraocular movement was compromised postoperatively, although in the other five patients there was no aggravation of the neurologic signs. Follow-up CT scans and MRI demonstrated no recurrent tumors nor any enlargement of residual tumors. Based on these findings, we advocate aggressive surgical removal of these tumors, which should be augmented by radiation therapy if the postoperative CT scans or MRI reveal residual tumors. ImagesFigure 1Figure 2Figure 3Figure 4Figure 5Figure 6Figure 7Figure 8Figure 9Figure 10 PMID:17170863

  14. Biomaterials in skull base surgery

    PubMed Central

    Maier, Wolfgang

    2011-01-01

    Reconstruction materials and techniques for the base of the skull have undergone rapid developments and differentiation in recent years. While mostly autotransplants, collagens or resorbable alloplastic materials are preferred for duraplasties, pronounced organ-specific differences can be observed in the reconstruction of hard tissues. The use of polymethylmethacryl bone cement, once wide-spread, has decreased greatly due to the release of toxic monomers. Bony autotransplants are still used primarily for smaller skull-base defects, intraoperatively formable titanium nets may be also used for larger fronto- or laterobasal reconstructions of bony defects. Defects in visible areas are increasingly closed with preformed titanium or ceramic implants, which are planned and fitted to the individual patient using preoperative CT imaging. At the skull base, this applies especially to reconstructions of the frontal sinus. For extensive reconstructions of the orbita, titanium nets and non-resorbable plastics have proven valuable; in closing smaller defects especially of the orbital floor, resorbable implants based on Polyglactin 901 are also used. PMID:22073100

  15. 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.

  16. 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

  17. 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. PMID:2066727

  18. Aspergillus Osteomyelitis of the Skull.

    PubMed

    Nicholson, Simon; King, Richard; Chumas, Paul; Russell, John; Liddington, Mark

    2016-07-01

    Osteomyelitis of the craniofacial skeleton is rare, with fungal pathogens least commonly implicated. The authors present 2 patients of osteomyelitis of the skull caused by Aspergillus spp. and discuss the diagnosis, clinicopathological course, and management strategies.Late recurrence seen in this type of infection warrants long-term follow-up and a high index of suspicion for the clinical signs associated with recurrence.Such patients would benefit from their surgical debridement being planned and managed via a specialist craniofacial unit, so as to utilize the most aesthetically sensitive approach and the experience of specialists from several surgical disciplines. PMID:27391523

  19. 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

  20. 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. PMID:12198345

  1. The growth of the brain and skull in children.

    PubMed

    Mann, M D

    1984-04-01

    Published data for brain weight and head circumference in children were examined to determine whether there was evidence for development of brain size in 'spurts' rather than continuously. Graphical methods and various statistical analyses were used to detect significant deviations from a smooth progression in growth of the brain or skull. No convincing evidence for other than normal statistical sampling variations was found for either brain size or head circumference. It is premature to begin reorganization of school curriculae on the grounds that the brains of children grow in spurts. PMID:6722584

  2. 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.

  3. 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. PMID:26018014

  4. 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

  5. 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.

  6. 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

  7. 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

  8. Management of osteomyelitis of the skull base.

    PubMed

    Benecke, J E

    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. PMID:2601534

  9. The Genetics of Canine Skull Shape Variation

    PubMed Central

    Schoenebeck, Jeffrey J.; Ostrander, Elaine A.

    2013-01-01

    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. PMID:23396475

  10. 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...

  11. 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....

  12. 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....

  13. 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....

  14. 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...

  15. 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...

  16. 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...

  17. 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....

  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 882.4460 - 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... 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....

  20. Skull melting of fluorophosphate glass results

    SciTech Connect

    Wenckus, J.F.

    1982-06-07

    The results are presented of the third fluorophosphate glass skull-melting experiment which was carried out on July 30th. Details of the experimental procedures used were described in the report dated March 10, 1981.

  1. 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

  2. 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

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

    PubMed Central

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

    2015-01-01

    Summary 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

  4. Conductivities of three-layer human skull

    NASA Astrophysics Data System (ADS)

    Akhtari, Massoud

    Electrical conductivities of compact, spongiosum, and bulk layers of the cadaver, live, and dead (corpse) human skull were determined at a number of frequencies and electric fields at room temperature using the four-electrode method. Current was applied and withdrawn over the top and bottom surfaces of each sample and potential drop across different layers was measured. A model that considers variations in skull thicknesses is used to determine the conductivity of the tri-layer skull and its individual anatomical structures. The results indicate that the conductivities of the spongiform (cadaver ˜ 5.4--11.5, live skull ˜ 16.2--41.1, dead ˜ 39.7--99.3 milliS/m), the top compact (cadaver ˜ 0.8--1.8, live ˜ 5.4--7.2, dead ˜ 5.4--12.3 milliS/m) and lower compact (cadaver ˜ 2.8--5.1, live ˜ 2.8--10.2, dead ˜ 5.2--19.3 milliS/m) layers of the skull have significantly different and inhomogeneous conductivities. The conductivities of the skull layers are frequency dependent in the 10--90 Hz region and are non-ohmic in the 0.45--2.07 A/m2 region.

  5. 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

  6. 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

  7. 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

  8. 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 ...

  9. 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. PMID:24721358

  10. Endoscopic skull base training using 3D printed models with pre-existing pathology.

    PubMed

    Narayanan, Vairavan; Narayanan, Prepageran; Rajagopalan, Raman; Karuppiah, Ravindran; Rahman, Zainal Ariff Abdul; Wormald, Peter-John; Van Hasselt, Charles Andrew; Waran, Vicknes

    2015-03-01

    Endoscopic base of skull surgery has been growing in acceptance in the recent past due to improvements in visualisation and micro instrumentation as well as the surgical maturing of early endoscopic skull base practitioners. Unfortunately, these demanding procedures have a steep learning curve. A physical simulation that is able to reproduce the complex anatomy of the anterior skull base provides very useful means of learning the necessary skills in a safe and effective environment. This paper aims to assess the ease of learning endoscopic skull base exposure and drilling techniques using an anatomically accurate physical model with a pre-existing pathology (i.e., basilar invagination) created from actual patient data. Five models of a patient with platy-basia and basilar invagination were created from the original MRI and CT imaging data of a patient. The models were used as part of a training workshop for ENT surgeons with varying degrees of experience in endoscopic base of skull surgery, from trainees to experienced consultants. The surgeons were given a list of key steps to achieve in exposing and drilling the skull base using the simulation model. They were then asked to list the level of difficulty of learning these steps using the model. The participants found the models suitable for learning registration, navigation and skull base drilling techniques. All participants also found the deep structures to be accurately represented spatially as confirmed by the navigation system. These models allow structured simulation to be conducted in a workshop environment where surgeons and trainees can practice to perform complex procedures in a controlled fashion under the supervision of experts. PMID:25294050

  11. Cavernomas of the skull: review of the literature 1975-2000.

    PubMed

    Heckl, Stefan; Aschoff, Alfred; Kunze, Stefan

    2002-03-01

    We describe four patients with intraosseous cavernous hemangiomas of the skull which were localized supraorbitally, parietally (two cases), and occipitally. The diameter ranged from 15 mm to 25 mm. They presented with slowly growing mass, tender to pressure, with spontaneous pain, and with freely mobile skin above the cavernoma sites. Magnetic resonance imaging (hyperintensity on T2 and isointensity with brain on T1) and CT (osteolytic lesion with erosion of the tabula externa) confirmed the plain skull films showing the honeycomb or sunburst appearance pattern. Resections and postoperative course were uneventful. In three of these cases there was coexistence with tumors (meningeoma, malignant lymphoma, and malignant melanoma); none of these constellations has been described before. Generally, cavernous hemangiomas of the skull are rare. There is one extensive review published by Barnes in 1984 regarding a period of 136 years with 123 intraosseous hemangiomas of the skull and 74 of the jaws. Unfortunately, the histological confirmation is not completely clear and some capillary hemangiomas are included. In a review of the literature since 1975, we found 103 histologically proven intraosseous cavernous hemangiomas of the skull (with our four cases included) and 22 of the jaws, which are shown in an overview with respect to their localization. The most frequent site was frontal, followed by temporal. PMID:11954766

  12. 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.

  13. 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

  14. 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.

  15. Analysis of 429 fractures in 189 battered children.

    PubMed

    King, J; Diefendorf, D; Apthorp, J; Negrete, V F; Carlson, M

    1988-01-01

    To assess empirically the radiologic appearance of fractures among victims of child abuse, the charts and radiographs of 189 battered children exhibiting fractures (n = 429 total fractures) were studied. Approximately one-half of the patients had a single fracture. Bones most commonly fractured were the humerus, femur, and tibia; transverse fractures were the most common type. Of long bone fractures, the middle third (50%) and distal third (41%) locations were most prominent. Age, race, and gender were not associated with any particular long bone fracture type. Skull fractures were the only type more likely to be present in children aged less than 1 year than in older children (p less than 0.05, one-tailed). In the past, emphasis has been placed on corner fractures, fractures at different stages of healing, and injuries at several sites. Our results suggest that fresh single diaphyseal fractures are more common. PMID:3170740

  16. 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 usually occurs after an injury and often occurs with ...

  17. [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

  18. [Fibrous dysplasia of the skull. Radiologic diagnosis].

    PubMed

    Amato, C; Moschini, M; Colavita, N; Tagliaferri, G

    1993-09-01

    The authors examined 11 patients with fibrous dysplasia of the skull pointing out its radiologic features and preferential sites. Conventional radiology, CT and MR imaging were used. As for conventional radiology, tangential scans which of great value to depict the most typical morphologic patterns. Lesions of the skull base were most frequent in the sphenoid (7 of 11 cases), where 5 of 7 exhibited a sclerotic pattern. Bone changes in the skull vault were: mixed (3 cases), pagetoid (2 cases), "ground glass" (1 case) and lytic (1 case): none of these cases was of the sclerotic type. A typical feature of vault lesions was the widening of diploic space associated with expansion of the outer bone and integrity of the inner bone. Radiologic findings, often associated with suggestive clinical manifestations, always allowed a diagnostic hypothesis; histopathologic confirmation was needed only in a few cases (4 of 11 patients). PMID:8210526

  19. Waterflood-induced fractures

    SciTech Connect

    Dikken, B.J.; Niko, H.

    1987-01-01

    Fracturing occurs quite often in water injection wells, with sometimes unforeseen consequences on waterflood sweep efficiency. One of the causes of fracturing is often the cooling of hot formations by cold injection water. A special version of a thermal reservoir simulator for prototype applications has thus been constructed that is capable of dealing with propagating waterflood-induces hydraulic fractures. With this simulator, fracture propagation and the effect of growing fractures on the sweep efficiency are studied. Infinite fracture conductivity is assumed. The limitation to a very high leak-off fractures justifies disregarding the changes in fracture volume. Fracture growth is calculated using the concept of a critical stress intensity factor. Both poro- and thermo-elastic changes in the horizontal stresses are calculated numerically and their influence on the fracture initiation/propagation is continuously taken into account. In addition, a model of fracture wall impairment because of filter-cake build-up due to poor quality injection water is included. Results are presented for both thermal and isothermal situations. It is observed in isothermal cases that the voidage replacement ratio (volume balance during injection) determined to a great extent the length to which the fracture eventually may grow.

  20. Pathologic aspects of skull base tumors.

    PubMed

    Marszałek, Andrzej; Szylberg, Łukasz; Wiśniewski, Sławomir

    2016-01-01

    Skull base tumors form a highly heterogeneous group. As there are several structures in this anatomical site, a large number of different primary malignancies might develop, as well as a variety of secondary (metastatic) tumors. In this article, the most common malignancies are presented, along with a short histopathologic description. For some entities, an immunohistochemical profile is also given that should be helpful in proper diagnosis. As many pathologic diagnoses nowadays also include genetic studies, the most common genetic abnormalities in skull base tumors are presented. PMID:27330415

  1. 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...

  2. 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...

  3. 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...

  4. 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...

  5. 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...

  6. Osteoporotic skull lesions in moose at Isle Royale National Park.

    PubMed

    Hindelang, M; Peterson, R O

    1996-01-01

    Osteoporotic lesions were evaluated in the skulls of moose (Alces alces) collected in Isle Royale National Park, Michigan (USA), from 1958 to 1994. Circular lesions which penetrated the outer table of the skull were distributed over the frontal and nasal bones asymmetrically in both sexes. About 32% of skulls recovered had some porotic lesions with slightly greater prevalence among males. PMID:8627919

  7. Orbital emphysema following remote skull trauma.

    PubMed

    Brown, S M; Lissner, G

    1995-06-01

    In an unusual case of orbital emphysema following nose blowing, a reliable patient history and examination demonstrated no direct trauma to the orbit. Blunt posterior skull trauma was sustained several hours before the development of the orbital emphysema. A "seismic" transmittal of force to the orbital walls is postulated. PMID:7654620

  8. 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.

  9. 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

  10. Surgical Resectability of Skull Base Meningiomas.

    PubMed

    Goto, Takeo; Ohata, Kenji

    2016-07-15

    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

  11. 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

  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. 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

  14. 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

  15. 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

  16. 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.

  17. [Orbitozygomatic approaches to the skull base].

    PubMed

    Cherekaev, V A; Gol'bin, D A; Belov, A I; Radchenkov, N S; Lasunin, N V; Vinokurov, A G

    2015-01-01

    The paper is written in the lecture format and dedicated to one of the main basal approaches, the orbitozygomatic approach, that has been widely used by neurosurgeons for several decades. The authors describe the historical background of the approach development and the surgical technique features and also analyze the published data about application of the orbitozygomatic approach in surgery for skull base tumors and cerebral aneurysms. PMID:26529627

  18. Neurological susceptibility to a skull defect

    PubMed Central

    Honeybul, Stephen

    2014-01-01

    Background: There continues to be considerable interest in the use of decompressive craniectomy in the management of neurological emergencies. The procedure is technically straightforward; however, it is becoming increasingly apparent that it is associated with significant complications. One complication that has received relatively little attention is the neurological dysfunction that can occur due to the absence of the bone flap and the subsequent distortion of the brain under the scalp as cerebral swelling subsides. The aim of this narrative review was to examine the literature available regarding the clinical features described, outline the proposed pathophysiology for these clinical manifestations and highlight the implications that this may have for rehabilitation of patients with a large skull defect. Methods: A literature search was performed in the MEDLINE database (1966 to June 2012). The following keywords were used: Hemicraniectomy, decompressive craniectomy, complications, syndrome of the trephined, syndrome of the sinking scalp flap, motor trephined syndrome. The bibliographies of retrieved reports were searched for additional references. Results: Various terms have been used to describe the different neurological signs and symptoms with which patients with a skull defect can present. These include; syndrome of the trephined, posttraumatic syndrome, syndrome of the sinking scalp flap, and motor trephined syndrome. There is, however, considerable overlap between the conditions described and a patient's individual clinical presentation. Conclusion: It is becoming increasingly apparent that certain patients are particularly susceptible to the presence of a large skull defect. The term “Neurological Susceptibility to a Skull Defect” (NSSD) is therefore suggested as a blanket term to describe any neurological change attributable to the absence of cranial coverage. PMID:25024883

  19. Skull metastasis from rectal gastrointestinal stromal tumours.

    PubMed

    Gil-Arnaiz, Irene; Martínez-Trufero, Javier; Pazo-Cid, Roberto Antonio; Felipo, Francesc; Lecumberri, María José; Calderero, Verónica

    2009-09-01

    Gastrointestinal stromal tumours (GIST) are the most common mesenchymal neoplasm of the gastrointestinal tract. Rectum localisation is infrequent for these neoplasms, accounting for about 5% of all cases. Distant metastases of GIST are also rare. We present a patient with special features: the tumour is localised in rectum and it has an uncommon metastatic site, the skull, implying a complex differential diagnosis approach. PMID:19776004

  20. 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. PMID:25863692

  1. [Modern skull base surgery from the perspective of neurosurgeons].

    PubMed

    Spetzger, U

    2011-04-01

    At present, modern skull base surgery is a highly sophisticated interdisciplinary collaboration of various diagnostic and therapeutic disciplines. The overall goal is the treatment of complex tumorous, traumatic, vascular and inflammatory processes or developmental disorders of the skull base with preservation of function. The paper presents modern concepts, procedures and minimally invasive strategies in skull base surgery and also critically discusses the current trend to endoscopic and robot-assisted surgical techniques. PMID:21647829

  2. Device and method for skull-melting depth measurement

    DOEpatents

    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.

  3. 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.

  4. Skull Optical Clearing Solution for Enhancing Ultrasonic and Photoacoustic Imaging.

    PubMed

    Yang, Xiaoquan; Zhang, Yang; Zhao, Kai; Zhao, Yanjie; Liu, Yanyan; Gong, Hui; Luo, Qingming; Zhu, Dan

    2016-08-01

    The performance of photoacoustic microscopy (PAM) degrades due to the turbidity of the skull that introduces attenuation and distortion of both laser and stimulated ultrasound. In this manuscript, we demonstrated that a newly developed skull optical clearing solution (SOCS) could enhance not only the transmittance of light, but also that of ultrasound in the skull in vitro. Thus the photoacoustic signal was effectively elevated, and the relative strength of the artifacts induced by the skull could be suppressed. Furthermore in vivo studies demonstrated that SOCS could drastically enhance the performance of photoacoustic microscopy for cerebral microvasculature imaging. PMID:26886977

  5. 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.

  6. 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

  7. Unfavourable results in skull base surgery

    PubMed Central

    Jaju, Hemen

    2013-01-01

    Treatment of skull base tumors involves multiple specialities. The lesions are usually advanced and the treatment is often associated with unfavorable results, which may be functional and/or aesthetic. Here we have done an analysis for the complications and unfavorable results of 546 cases treated surgically by a single craniofacial surgeon over a period of 14 years. The major morbidity ranges from death to permanent impairment of vital organ functions (brain, eye, nose), infections, tissue losses, flap failures, treatment associated complications, psychosocial issues, and aesthesis besides others. This article is aimed at bringing forth these unfavorable results and how to avoid them. PMID:24501460

  8. Spontaneous acute epidural hematoma developed due to skull metastasis of hepatocelluar carcinoma: A case report and review of the literature

    PubMed Central

    KIM, YOU-SUB; MOON, KYUNG-SUB; LEE, KYUNG-HWA; JUNG, TAE-YOUNG; JANG, WOO-YOUL; KIM, IN-YOUNG; JUNG, SHIN

    2016-01-01

    Acute epidural hematoma (AEDH) is one of the most common pathological types of head trauma, and may develop without an accidental event, although this is uncommon. The present study reports the case of a 41-year-old male patient that developed spontaneous AEDH due to skull metastasis of hepatocellular carcinoma (HCC). The man was admitted to Chonnam National University Hwasun Hospital and Medical School due to drowsiness and right-sided hemiparesis. A computed tomography scan of the head revealed the presence of a large AEDH and a lytic bone lesion in the left posterior fossa and parieto-occipital region, which exhibited heterogeneous enhancement. The perioperative findings revealed a large amount of mixed-stage epidural hematoma and a soft hemorrhagic mass that exhibited lytic change on the occipital bone. No evidence of head trauma, such as skull fracture or scalp contusion, was detected. The pathological diagnosis was hematoma with metastatic HCC. The current study reports the rare case of a patient with a metastatic tumor located in the skull that resulted in the development of spontaneous AEDH. Once a sudden and unpredicted neurological deficit occurs in a patient with HCC that is also diagnosed with skull metastasis, the possibility of spontaneous AEDH developing from the metastasis should be considered. PMID:26870277

  9. 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

  10. 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

  11. Cranial fractures and direction of fire in low velocity gunshots.

    PubMed

    Betz, P; Stiefel, D; Eisenmenger, W

    1996-01-01

    A total of 59 penetrating contact shot wounds to the head caused by handguns was investigated and a comparison was made between the magnitude and the number of fracture lines at the entrance and exist site of the vault and at the base of the skull. It was noted that in approximately 50% of the cases the extent of fractures at the entrance site exceeded those at the exit wound while in the remaining individuals no relevant differences or even greater exit fractures were found. Furthermore, no close correlation between the fracture patterns of the vault and at the base of the skull occurred indicating that differences in the magnitude and the number of entrance or exit fracture lines cannot provide reliable information on direction of fire. Additionally, no further conclusions on the gun used can be drawn from differences in the entrance and exit fracture patterns. It can only be assumed that the absence of fractures in the cranial fossae points to the use of small calibre handguns (< or = 7.65 mm) while a fragmentation of the skull can as a rule be expected after shots from guns with larger calibres (> 7.65 mm). PMID:8912048

  12. 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

  13. 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

  14. Copper Beaten Skull! Can It be a Usual Appearance?

    PubMed

    Desai, Vela; Priyadarshini, Smita R; Sharma, Rajeev

    2014-01-01

    'Copper beaten' skull refers to the prominent convolutional markings seen in multiple bones of the skull. Underlying cause is thought to be related to increased intracranial pressure resulting from such processes as craniosynostosis, obstructive hydrocephalus and/or intracranial masses. However, the copper beaten appearance of the skull has poor sensitivity in detecting increased intracranial pressure as such an appearance can also be seen in normal patients. In this article, we have reported a case of a 5 years old child with classical features of beaten silver skull. How to cite this article: Desai V, Priyadarshini SR, Sharma R. Copper Beaten Skull! Can It be a Usual Appearance? Int J Clin Pediatr Dent 2014;7(1):47-49. PMID:25206238

  15. 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)

  16. 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

  17. 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.

  18. 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

  19. Characteristics of gunshot wounds in the skull.

    PubMed

    Quatrehomme, G; Işcan, M Y

    1999-05-01

    The analysis of trauma to the skeleton is an important aspect of forensic case work, but most pathology references devote limited attention to this topic. This paper describes various aspects of gunshot wounds, including entrance and exit patterns, angle and path, range of fire and velocity, and caliber of the bullet, based on observations of a series of known cases. Skeletal remains of 21 victims of gunshot wounds were studied. In most cases, there was documentation of the investigation, autopsy, and victim's identity. Each case was analyzed in terms of wound location, shape, size and exit/entry surface area ratio, beveling, and direction of shooting Skull entry wounds were most often round or oval. Unusual shapes were observed in bones like the mandible and mastoid process, but were also found to be triangular, nearly rectangular or irregular. Tunneling was observed in the mastoid process. The expected internal beveling was obvious in all but one skull. External beveling of an entry wound was only observed in one case (parietal bone). Exit wounds were roughly round, oval, square, and rectangular and were always more irregular than entry wounds. External beveling of exit wounds was observed in most vault bones, but there was none in the orbit, maxilla, greater wing of the sphenoid, temporal, or left occipital bone. Tangential gunshot wounds were seen in a mastoid process, zygomatic process, mandibular ramus and condyle, and occipital condyle. Most of the exit to entry surface area ratios (cm2) varied from 1.4 to 2.0. In four cases the ratio indicated that entrances were larger than exists. In conclusion, understanding of gunshot wound characteristics is an important matter to interpret distance, velocity, direction and sometimes caliber size. Assessment of this nature of gunshot wounds helps reconstruct events surrounding the death. PMID:10408112

  20. Applied anatomy of the anterior cranial fossa: what can fracture patterns tell us?

    PubMed

    Stephens, J R; Holmes, S; Evans, B T

    2016-03-01

    The skull base is uniquely placed to absorb anteriorly directed forces imparted either via the midfacial skeleton or cranial vault. A variety of skull base fracture classifications exist. Less well understood, however, is fracture extension beyond the anterior cranial fossa (ACF) into the middle and posterior cranial fossae. The cases of 81 patients from two UK major trauma centres were studied to examine the distribution of fractures across the skull base and any relationship between the vector of force and extent of skull base injury. It was found that predominantly lateral force to the craniofacial skeleton produced a fracture that propagated beyond the ACF into the middle cranial fossa in 77.4% of cases, significantly more (P<0.001) than for predominantly anterior force (12.0%). Fractures were significantly more likely to propagate into the posterior fossa with a lateral vector of impact compared to an anterior vector (P=0.049). This difference in energy transfer across the skull base may, in part, be explained by the local anatomy. The more delicate central ACF acts as a 'crumple zone' in order to absorb force. Conversely, no collapsible interface exists in the lateral aspect of the ACF, thus the lateral ACF behaves like a 'buttress', resulting in increased energy transfer. PMID:26589135

  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. 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

  3. 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.

  4. 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.

  5. 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

  6. 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

  7. Transoral robotic surgery of the central skull base: preclinical investigations.

    PubMed

    Fernandez-Nogueras, F J J; Katati, M J; Arraez Sanchez, M A; Molina Martinez, M; Sanchez Carrion, M

    2014-06-01

    In this study we explored possible applications of the da Vinci system in approaching the skull base at optic chiasm level on two cryopreserved cadavers, using an entirely transoral robotic technique (TORS). We used a standard 12 mm endoscopy and 8 mm terminals. Bone drilling was performed manually. The da Vinci system is equipped with very good illumination and 3D viewing, thus providing excellent vision and great maneuverability even in the less accessible areas of the skull. Our experience demonstrates that an entirely transoral skull base robotic approach to this complex anatomical region has many advantages as compared to traditional techniques. PMID:24077869

  8. 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

  9. Former and present aspects in neuro-skull architecture.

    PubMed

    Niculescu, M C; Niculescu, V; Jianu, Adelina; Zăvolan, M; Motoc, A

    2006-01-01

    The classical authors considered the functional resistance of the neuro-skull to consist of arcs at the arch level, rafters at the base and pillars at the joint of the arcs and rafters, those last also connecting the neuro-skull framework and that of the viscero-skull. The new outlooks replace the term pillar with that of resistance node and assemble the arcs and rafters within common structures, named resistance belts. The belts are: one in transversal, three sagittal, two in frontal plane and two oblique positions. At the intersection of the belts, the resistance nodes are placed. PMID:17308689

  10. [Trochanteric femoral fractures].

    PubMed

    Douša, P; Čech, O; Weissinger, M; Džupa, V

    2013-01-01

    At the present time proximal femoral fractures account for 30% of all fractures referred to hospitals for treatment. Our population is ageing, the proportion of patients with post-menopausal or senile osteoporosis is increasing and therefore the number of proximal femoral fractures requiring urgent treatment is growing too. In the age category of 50 years and older, the incidence of these fractures has increased exponentially. Our department serves as a trauma centre for half of Prague and part of the Central Bohemia Region with a population of 1 150 000. Prague in particular has a high number of elderly citizens. Our experience is based on extensive clinical data obtained from the Register of Proximal Femoral Fractures established in 1997. During 14 years, 4280 patients, 3112 women and 1168 men, were admitted to our department for treatment of proximal femoral fractures. All patients were followed up until healing or development of complications. In the group under study, 82% were patients older than 70 years; 72% of those requiring surgery were in their seventies and eighties. Men were significantly younger than women (p<0.001) and represented 30% of the group. The fractures were 2.3-times more frequent in women than in men. In the category under 60 years, men significantly outnumbered women (p<0.001). The patients with pertrochanteric fractures were, on the average, eight years older than the patients with intertrochanteric fractures, which is a significant difference (p<0.001). The mortality rate within a year of injury was about 30%. Trochanteric fractures accounted for 54.7% and femoral neck fractures for 45.3% of all fractures. The inter-annual increase was 5.9%, with more trochanteric than femoral neck fractures. There was a non-significant decrease in intertrochanteric (AO 31-A3) fractures. On the other hand, the number of pertrochanteric (AO 31-A1+2) fractures increased significantly (p<0.001). A total of 1 394 fractures were treated with a proximal

  11. 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. PMID:21816324

  12. 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

  13. 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

  14. 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%.

  15. Comparison of skull and femur lead levels in adult rats

    SciTech Connect

    Denton, J.E.; Potter, G.D.; Santolucito, J.A.

    1980-12-01

    The purpose of the study was to elucidate the relationship between skull and femur lead levels in laboratory rats. Forty-eight female rats were given one of four lead chloride drinking water solutions: 0.05, 0.58, 17, or 352 ppM lead. Two animals from each group were sacrificed after 3, 6, 9, 12, 15, and 24 weeks of treatment. Both femurs and the frontal and parietal bones of the skull were removed from each animal and analyzed for lead concentration by atomic absorption spectroscopy. A significant accumulation of lead was observed in femurs and skull bones only from animals in the 352 ppM lead treatment group. The lead concentrations of the femurs were significantly higher than skull lead concentrations for all groups and this relationship was described using a linear regression equation.

  16. 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

  17. Sinonasal Non-Hodgkin's Lymphoma with Skull Base Involvement

    PubMed Central

    Dare, Amos O.; Datta, Rajiv V.; Loree, Thom R.; Hicks, Wesley L.; Grand, Walter

    2001-01-01

    Non-Hodgkin's lymphoma (NHL) is a rare tumor of the skull base. As the incidence of primary central nervous system (CNS) lymphoma has increased, atypical presentations involving the skull or cranial base exclusively have been reported. In immunocompetent patients with no previous history or predisposing factors, the diagnosis of primary NHL of the skull base may be delayed. We present four cases of nasal and paranasal sinus NHL with both skull base and intracranial involvement in immunocompetent patients. Clinicopathologic correlation suggests that cranial base and intracranial involvement with NHL represents advanced-stage primary sinonasal disease. Surgical biopsy before definitive treatment is recommended. Radiation therapy provides local control; adjuvant chemotherapy after primary radiation therapy may be required for recurrent disease. ImagesFigure 1Figure 2Figure 3 PMID:17167612

  18. 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

  19. Historical evidence of the 1936 Mojokerto skull discovery, East Java.

    PubMed

    Huffman, O Frank; Shipman, Pat; Hertler, Christine; de Vos, John; Aziz, Fachroel

    2005-04-01

    To resolve ambiguities in the literature, we detail the discovery history of the Mojokerto child's skull (Perning 1), employing letters, maps, photographs, reports, and newspaper accounts not previously used for this purpose. Andoyo, an experienced vertebrate-fossil collector with the Geological Survey of the Netherlands Indies, found the skull on February 13, 1936, while collecting for Johan Duyfjes, who had mapped the field area geologically. On February 18-19 Andoyo sent the fossil and a 1:25,000-topographic map showing the discovery point to Survey headquarters. The locality lies between Perning and Sumbertengu villages, approximately 10km northeast of Mojokerto city, East Java. G.H. Ralph von Koenigswald, Survey paleontologist, identified the specimen as Pithecanthropus and then named it Homo modjokertensis (it is now accepted as Homo erectus). Unfortunately he confused the discovery record in a March 28 newspaper article by characterizing the skull as a "surface find" [Dutch: oppervlaktevondst] while also attributing it to ancient beds. von Koenigswald probably had insufficient basis for either assertion, having not yet talked to Andoyo or Duyfjes. Eugene Dubois challenged von Koenigswald on the "surface-find" issue, Andoyo was consulted, and Duyfjes went to the site. Duyfjes and von Koenigswald then published scientific papers stating that the skull was unearthed 1m deep from a hill-slope outcrop of conglomeratic sandstone in Duyfjes' Pucangan formation. A cross section by Andoyo, which may show the Mojokerto site, also indicates a skull at 1m depth in conglomeratic sandstone. Photographs taken in 1936-1938 show a shallow pit at a single field location that fits Duyfjes' site description and is identified as the Mojokerto-skull site in 1940-1943 publications. By WWII the scientific community accepted the skull as an early hominid. Although von Koenigswald's "surface-find" comment remains a source of doubt in the record, we consider in situ discovery for the

  20. 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

  1. "Bochdalek's" skull: morphology report and reconstruction of face.

    PubMed

    Klepáček, Ivo; Malá, Pavla Zedníková

    2012-12-01

    The objective of this study was to create a real model of a face using the well preserved "Bochdalek's skull" (from an eighteenth Century female aged 18 years) kept in the museum of anatomy (Institute of Anatomy, 1st Medical Faculty, Charles University in Prague). The skull had previously been appraised as a deformed skull with an adhesion present on both sides of the jaw, most likely of post-traumatic origin (bilateral syngnathia). In an attempt to find the best description for it, and to identify the spatial relationships between the surface of the facial bones which had changed in shape, as well as the formation of soft tissue on the face, we decided to perform a 3D reconstruction of the face. Due to the necessity of preserving the unique original undamaged skull, we created an exact digital "casting" of the facial bone structure on a computer first, which we then converted into a three-dimensional model using a 3D RepRap printer. We needed to take into consideration the fact that we had no portrait of the girl, just the skull. For this reason, we opted for a selected combination of anthropologic steps (the modified Manchester technique), which in our view, allows for optimum creation of the topography of the face in keeping with the deformed skull. The resulting reconstructed face was old in appearance with an overhanging lower lip and flattened surfaces in the areas of the temporalis and masseter muscles. PMID:22918853

  2. [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

  3. [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. PMID:17425001

  4. 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. PMID:26010648

  5. Hemostasis in Endoscopic Endonasal Skull Base Surgery.

    PubMed

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

    2015-08-01

    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

  6. Spontaneous Resorption of a Penetrating Orbital Bone Fracture Fragment.

    PubMed

    Campbell, Ashley A; Cunnane, Mary Elizabeth; Dunn, Gavin P; Gray, Stacy Tutt; Lefebvre, Daniel R

    2015-01-01

    The authors describe a 20-year-old man who sustained multiple facial fractures in a high-speed motor vehicle crash, including a bone fragment from a skull base fracture that penetrated the orbital soft tissues superomedially. Serial CT scans documented spontaneous resorption over a 6-month period. While it is known that autologous bone grafts used in craniofacial reconstruction exhibit variable amounts of bone resorption, the complete resorption of an intraorbital fracture fragment has not been documented in the literature. His clinical care and the report of his case were undertaken in a fashion in accordance with the principles of the Health Insurance Portability and Accountability Act regulations. PMID:24833452

  7. 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…

  8. 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

  9. Modeling the vertical confinement of injection-well thermal fractures

    SciTech Connect

    Clifford, P.J.; Berry, P.J.; Gu, H. )

    1991-11-01

    Cooling of rock by water injection frequently causes fracturing of wells. This paper describes a 3D simulation model of thermally induced fracturing. It is used to show that fractures often tend to grow vertically into permeable zones. Procedures are outlined for confining fracture growth in wells where it will assist waterflood sweep performance.

  10. 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

  11. 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 ...

  12. Olecranon Fractures.

    PubMed

    Brolin, Tyler J; Throckmorton, Thomas

    2015-11-01

    Olecranon fractures are common upper extremity injuries, with all but nondisplaced fractures treated surgically. There has been a recent shift in the surgical management of these fractures from tension band wiring to locking plate fixation and intramedullary nailing; however, this comes with increased implant cost. Although most patients can expect good outcomes after these various techniques, there is little information to guide a surgeon's treatment plan. This article reviews the epidemiology, classification, treatment, and outcomes of olecranon fractures. PMID:26498547

  13. 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

  14. 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.

  15. Skull base defect in a patient with ozena undergoing dacryocystorhinostomy

    PubMed Central

    Earley, Marisa A.; Eloy, Jean Anderson

    2011-01-01

    Ozena, which is often used interchangeably with atrophic rhinitis or empty nose syndrome, is a progressive and chronically debilitating nasal disease that results in atrophy of the nasal mucosa, nasal crusting, fetor, and destruction of submucosal structures. Although the etiology is not completely understood, infection with Klebsiella ozaenae is widely believed to contribute to the destructive changes. We present a case of a patient with ozena secondary to K. ozaenae with extensive destruction of bony structures of the nasal cavity undergoing elective dacryocystorhinostomy. An extensively thinned skull base secondary to the disease process resulted in an unforeseen complication in which the skull base was entered leading to a cerebrospinal fluid leak. Patients with known history of ozena or atrophic rhinitis often have extensive destruction of the lateral nasal wall and skull base secondary to progression of disease. Submucosal destruction of these bony structures mandates the need for extreme caution when planning on performing endoscopic intervention at or near the skull base. If physical examination or nasal endoscopy is suspicious for atrophic rhinitis or a patient has a known history of infection with K. ozaenae, we recommend preoperative imaging for surgical planning with careful attention to skull base anatomy. PMID:22852113

  16. 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.

  17. 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

  18. [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

  19. Fracture Networks in Sea Ice

    NASA Astrophysics Data System (ADS)

    Vevatne, Jonas; Rimstad, Eivind; Hansen, Alex; Korsnes, Reinert; Hope, Sigmund

    2014-04-01

    Fracturing and refreezing of sea ice in the Kara sea are investigated using complex networkanalysis. By going to the dual network, where the fractures are nodes and their intersectionslinks, we gain access to topological features which are easy to measure and hence comparewith modeled networks. Resulting network reveal statistical properties of the fracturing process.The dual networks have a broad degree distribution, with a scale-free tail, high clusteringand efficiency. The degree-degree correlation profile shows disassortative behavior, indicatingpreferential growth. This implies that long, dominating fractures appear earlier than shorterfractures, and that the short fractures which are created later tend to connect to the longfractures.The knowledge of the fracturing process is used to construct growing fracture network (GFN)model which provides insight into the generation of fracture networks. The GFN model isprimarily based on the observation that fractures in sea ice are likely to end when hitting existingfractures. Based on an investigation of which fractures survive over time, a simple model forrefreezing is also added to the GFN model, and the model is analyzed and compared to the realnetworks.

  20. 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.

  1. 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

  2. [Two cases of tuberculosis of the skull cap (author's transl)].

    PubMed

    Memin, Y; Zurbach, J; Mafart, Y; Lesobre, B; Piéron, R; Hercend, T

    The authors report two cases of tuberculosis of the skull cap. The first in a Black African with heterozygous sickle cell disease also presenting with: tuberculosis of the cervical lymph nodes, subcutaneous frontal tumefactions bacteriologically confirmed to be of tuberculous origin, multiple lacunae of the vault from the same origin; the second case is an Asian woman having a multifocal tuberculous osteitis involving the skull, spine, pelvis and probably the same affection in the spleen. These cases are a reminder that the principal features of tuberculosis of the skull vault are very often associated with other tuberculous lesions, and to the problems of diagnosis it entails; the existence of a subcutaneous tumefaction of the vault or of any accessible site one can aspirate and/or perform biopsy constitutes a diagnostic aid. PMID:6244640

  3. Reconstruction Using Locoregional Flaps for Large Skull Base Defects.

    PubMed

    Hatano, Takaharu; Motomura, Hisashi; Ayabe, Shinobu

    2015-06-01

    We present a modified locoregional flap for the reconstruction of large anterior skull base defects that should be reconstructed with a free flap according to Yano's algorithm. No classification of skull base defects had been proposed for a long time. Yano et al suggested a new classification in 2012. The lb defect of Yano's classification extends horizontally from the cribriform plate to the orbital roof. According to Yano's algorithm for subsequent skull base reconstructive procedures, a lb defect should be reconstructed with a free flap such as an anterolateral thigh free flap or rectus abdominis myocutaneous free flap. However, our modified locoregional flap has also enabled reconstruction of lb defects. In this case series, we used a locoregional flap for lb defects. No major postoperative complications occurred. We present our modified locoregional flap that enables reconstruction of lb defects. PMID:26225296

  4. 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

  5. Sports fractures.

    PubMed Central

    DeCoster, T. A.; Stevens, M. A.; Albright, J. P.

    1994-01-01

    Fractures occur in athletes and dramatically influence performance during competitive and recreational activities. Fractures occur in athletes as the result of repetitive stress, acute sports-related trauma and trauma outside of athletics. The literature provides general guidelines for treatment as well as a variety of statistics on the epidemiology of fractures by sport and level of participation. Athletes are healthy and motivated patients, and have high expectations regarding their level of function. These qualities make them good surgical candidates. Although closed treatment methods are appropriate for most sports fractures, an aggressive approach to more complicated fractures employing current techniques may optimize their subsequent performance. PMID:7719781

  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. 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

  8. 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

  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. Removing Part of Skull After Severe Head Injury Brings Mixed Results

    MedlinePlus

    ... gov/news/fullstory_160857.html Removing Part of Skull After Severe Head Injury Brings Mixed Results More ... 8, 2016 (HealthDay News) -- Removing part of the skull to relieve pressure in the brain following a ...

  11. Segmentation, surface rendering, and surface simplification of 3-D skull images for the repair of a large skull defect

    NASA Astrophysics Data System (ADS)

    Wan, Weibing; Shi, Pengfei; Li, Shuguang

    2009-10-01

    Given the potential demonstrated by research into bone-tissue engineering, the use of medical image data for the rapid prototyping (RP) of scaffolds is a subject worthy of research. Computer-aided design and manufacture and medical imaging have created new possibilities for RP. Accurate and efficient design and fabrication of anatomic models is critical to these applications. We explore the application of RP computational methods to the repair of a pediatric skull defect. The focus of this study is the segmentation of the defect region seen in computerized tomography (CT) slice images of this patient's skull and the three-dimensional (3-D) surface rendering of the patient's CT-scan data. We see if our segmentation and surface rendering software can improve the generation of an implant model to fill a skull defect.

  12. Long-term outcome of extensive skull reconstruction using demineralized perforated bone in Siamese twins joined at the skull vertex.

    PubMed

    Salyer, K E; Gendler, E; Squier, C A

    1997-05-01

    The successful use of cortical demineralized perforated bone in the treatment of extensive skeletal defects in children is exemplified by this case involving Siamese twins joined at the skull vertex. Four years following extensive skull reconstruction using demineralized perforated bone, an examination revealed successful calvarial reconstruction in one twin. The other twin required additional implants of demineralized perforated bone to fill in defects. However, a histologic examination taken following this additional procedure revealed that these implants neither caused tissue reaction over a 4-year period, nor showed signs of resorption. Bony remodeling and new bone formation were in progress. Compared with other bone substitutes, demineralized perforated bone has proven to be effective in the treatment of large skull defects in children. PMID:9145145

  13. 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

  14. Hip fracture - discharge

    MedlinePlus

    Inter-trochanteric fracture repair - discharge; Subtrochanteric fracture repair - discharge; Femoral neck fracture repair - discharge; Trochanteric fracture repair - discharge; Hip pinning surgery - discharge

  15. 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

  16. Intracranial hypertension secondary to a skull lesion without mass effect.

    PubMed

    Serlin, Yonatan; Benifla, Mony; Kesler, Anat; Cohen, Avi; Shelef, Ilan

    2016-09-01

    We report and discuss five patients with intracranial hypertension due to a skull lesion reducing cerebral sinus patency with a compressive, non-thrombotic mechanism. We illustrate the importance of a high level of suspicion for this condition in patients presenting with headache, papilledema and increased intracranial pressure in the absence of focal signs or radiological evidence of mass effect. PMID:27283387

  17. Giant Cell Tumor of the Skull: Review of the Literature.

    PubMed

    Tamura, Ryota; Miwa, Tomoru; Shimizu, Kazuhiko; Mizutani, Katsuhiro; Tomita, Hideyuki; Yamane, Nobuo; Tominaga, Takehiro; Sasaki, Shunichi

    2016-05-01

    Background Giant cell tumors (GCTs) are rare in the skull. The present report describes a case with a primary GCT located in the temporal bone and reviews the relevant literature. We also propose a treatment strategy for GCT of the skull. Clinical Presentation A 41-year-old man presented with headache and auditory disturbance. Radiologic images showed a lytic expansive extradural lesion originating primarily from the right temporal bone and expanding into the middle cranial fossa and the infratemporal fossa. A biopsy specimen of the lesion was obtained from the external auditory meatus. Total removal was performed with temporal craniectomy, mandibular condylar process removal, tympanoplasty, and mastoidectomy. Discussion The rate of recurrence of GCTs is related to complete resection and location of the GCT rather than to the degree of invasiveness. Some of the mononuclear cells and stromal cells in GCT express receptor activator of nuclear factor κ-β ligand (RANKL). Because inhibition of RANKL and bisphosphonate therapy might eliminate giant cells, this approach might be useful for recurrent or unresectable GCTs of the skull. Conclusions Preoperative diagnosis by biopsy is important in determining the therapeutic strategy of GCTs. Complete resection is important to reduce the recurrence rate of GCTs in the skull. PMID:26091114

  18. Dynamic photophysical processes in laser irradiated human cortical skull bone

    NASA Astrophysics Data System (ADS)

    Mandelis, Andreas; Kwan, Chi-Hang; Matvienko, Anna

    2009-02-01

    Modulated luminescence (LUM) technique was applied to analyze photophysical processes in the cortical layer of human skull bones. The theoretical interpretation of the results was based on the optical excitation and decay rate equations of the fluorophore and on the molecular interaction parameter with the photon field density in the matrix of the bone. Using comparisons of the theory with the frequency response of dental LUM it was concluded that the optically active molecular species (fluorophore) in the bones is hydroxyapatite. An effective relaxation lifetime of skull cortical bone was derived theoretically and was found to depend on the intrinsic fluorophore decay lifetime, on the photon field density, and on the thickness of the bone. The experimentally measured dependencies were in excellent agreement with the theoretical model. The theory was able to yield measurements of the optical scattering coefficient, optical absorption coefficient, and mean coupling coefficient. These results show that the quantitative LUM can be used as a sensitive method to measure optical properties of the active fluorophore in cortical skull bones and the optical-field-induced molecular interaction parameter. When calibrated vs. laser intensity, the modulated luminescence can also be used to measure human skull thickness. These traits can be applied to monitor the bone mineral density (BMD) and, ultimately can be used as potential markers of bone health or disease, such as osteoporosis or bone cancer.

  19. 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…

  20. 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. PMID:24920571

  1. Advances in computed tomography evaluation of skull base diseases.

    PubMed

    Prevedello, Luciano M

    2014-10-01

    Introduction Computed tomography (CT) is a key component in the evaluation of skull base diseases. With its ability to clearly delineate the osseous anatomy, CT can provide not only important tips to diagnosis but also key information for surgical planning. Objectives The purpose of this article is to describe some of the main CT imaging features that contribute to the diagnosis of skull base tumors, review recent knowledge related to bony manifestations of these conditions, and summarize recent technological advances in CT that contribute to image quality and improved diagnosis. Data Synthesis Recent advances in CT technology allow fine-detailed evaluation of the bony anatomy using submillimetric sections. Dual-energy CT material decomposition capabilities allow clear separation between contrast material, bone, and soft tissues with many clinical applications in the skull base. Dual-energy technology has also the ability to decrease image degradation from metallic hardwares using some techniques that can result in similar or even decreased radiation to patients. Conclusions CT is very useful in the evaluation of skull base diseases, and recent technological advances can increase disease conspicuity resulting in improved diagnostic capabilities and enhanced surgical planning. PMID:25992136

  2. 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

  3. 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.

  4. 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

  5. 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

  6. 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

  7. 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

  8. 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.

  9. 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

  10. Variation of BMP3 Contributes to Dog Breed Skull Diversity

    PubMed Central

    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. PMID:22876193

  11. A new skull of early Homo from Dmanisi, Georgia.

    PubMed

    Vekua, Abesalom; Lordkipanidze, David; Rightmire, G Philip; Agusti, Jordi; Ferring, Reid; Maisuradze, Givi; Mouskhelishvili, Alexander; Nioradze, Medea; De Leon, Marcia Ponce; Tappen, Martha; Tvalchrelidze, Merab; Zollikofer, Christoph

    2002-07-01

    Another hominid skull has been recovered at Dmanisi (Republic of Georgia) from the same strata in which hominid remains have been reported previously. The Dmanisi site dated to approximately 1.75 million years ago has now produced craniofacial portions of several hominid individuals, along with many well-preserved animal fossils and quantities of stone artifacts. Although there are certain anatomical differences among the Dmanisi specimens, the hominids do not clearly represent more than one taxon. We assign the new skull provisionally to Homo erectus (=ergaster). The Dmanisi specimens are the most primitive and small-brained fossils to be grouped with this species or any taxon linked unequivocally with genus Homo and also the ones most similar to the presumed habilis-like stem. We suggest that the ancestors of the Dmanisi population dispersed from Africa before the emergence of humans identified broadly with the H. erectus grade. PMID:12098694

  12. 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

  13. 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

  14. 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

  15. 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

  16. Hypofractionated stereotactic radiation therapy in skull base meningiomas.

    PubMed

    Navarria, Pierina; Pessina, Federico; Cozzi, Luca; Clerici, Elena; Villa, Elisa; Ascolese, Anna Maria; De Rose, Fiorenza; Comito, Tiziana; Franzese, Ciro; D'Agostino, Giuseppe; Lobefalo, Francesca; Fogliata, Antonella; Reggiori, Giacomo; Fornari, Maurizio; Tomatis, Stefano; Bello, Lorenzo; Scorsetti, Marta

    2015-09-01

    To investigate the role of hypo-fractionated stereotactic radiation treatment (HSRT) in the management of skull base meningioma. Twenty-six patients were included in the study and treated with a dose of 30 Gy in 5 fractions with volumetric modulated arc therapy (RapidArc). Eighteen patients were symptomatic before treatment. Endpoints were local toxicity and relief from symptoms. Tumors were located in anterior skull base in 4/27 cases, in middle skull base in 12/27 and in posterior skull base in 11/27. HSRT was performed as first treatment in 17 (65 %) patients, in 9 (35 %) patients it followed a previous partial resection. Median follow up was 24.5 months (range 5-57 months). clinical remission of symptoms, complete or partial, was obtained in the vast majority of patients after treatment. Out of the 18 symptomatic patients, partial remission occurred in 9 (50 %) patients and complete remission in 9 (50 %). All asymptomatic patients retained their status after treatment. No severe neurologic toxicity grade III-IV was recorded. No increase of meningioma in the same site of treatment occurred; 16 (62 %) patients had stable disease and 9 (38 %) patients had tumor reduction. The mean tumor volume after treatment was 10.8 ± 17.8 cm(3) compared with 13.0 ± 19.1 cm(3) before treatment (p = 0.02). The mean actuarial OS was 54.4 ± 2.8 months. The 1- and 2-years OS was 92.9 ± 0.7 %. HSRT proved to be feasible for these patients not eligible to full surgery or to ablative radiation therapy. Local control and durability of results suggest for a routine application of this approach in properly selected cases. PMID:26040487

  17. Skull shapes of the Lissodelphininae: radiation, adaptation and asymmetry.

    PubMed

    Galatius, Anders; Goodall, R Natalie P

    2016-06-01

    Within Delphinidae, the sub-family Lissodelphininae consists of 8 Southern Ocean species and 2 North Pacific species. Lissodelphininae is a result of recent phylogenetic revisions based on molecular methods. Thus, morphological radiation within the taxon has not been investigated previously. The sub-family consists of ecologically diverse groups such as (1) the Cephalorhynchus genus of 4 small species inhabiting coastal and shelf waters, (2) the robust species in the Lagenorhynchus genus with the coastal La. australis, the offshore La. cruciger, the pelagic species La. obscurus and La. obliquidens, and (3) the morphologically aberrant genus Lissodelphis. Here, the shapes of 164 skulls from adults of all 10 species were compared using 3-dimensional geometric morphometrics. The Lissodelphininae skulls were supplemented by samples of Lagenorhynchus albirostris and Delphinus delphis to obtain a context for the variation found within the subfamily. Principal components analysis was used to map the most important components of shape variation on phylogeny. The first component of shape variation described an elongation of the rostrum, lateral and dorsoventral compression of the neurocranium and smaller temporal fossa. The two Lissodelphis species were on the high extreme of this spectrum, while Lagenorhynchus australis, La. cruciger and Cephalorhynchus heavisidii were at the low extreme. Along the second component, La. cruciger was isolated from the other species by its expanded neurocranium and concave facial profile. Shape variation supports the gross phylogenetic relationships proposed by recent molecular studies. However, despite the great diversity of ecology and external morphology within the subfamily, shape variation of the feeding apparatus was modest, indicating a similar mode of feeding across the subfamily. All 10 species were similar in their pattern of skull asymmetry, but interestingly, two species using narrowband high frequency clicks (La. cruciger and C

  18. Lytic Complications after Skull Reconstruction Using GeneX®

    PubMed Central

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

    2015-01-01

    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

  19. 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

  20. Atypical radiographic features of skull base cholesterol granuloma.

    PubMed

    Dinh, Christine T; Goncalves, Stefania; Bhatia, Rita; Truong, Kim; Telischi, Fred; Angeli, Simon; Morcos, Jacques; Eshraghi, Adrien A

    2016-06-01

    Cholesterol granulomas (CGs) are the most common benign lesions of the petrous apex (PA) and have distinct computed tomography (CT) and magnetic resonance imaging (MRI) characteristics. On CT, CGs of the PA (PACG) present as expansile lesions with erosion of bony trabeculae. MRI shows a hyperintense lesion on T1-and T2-weighted images and do not enhance with gadolinium. The objective is to describe the radiographic features of CGs of the skull base that do not arise from the PA. This study is a retrospective review. Three patients were operated on for suspected recurrent endolymphatic sac tumor, intracranial cholesteatoma, and recurrent sphenoid wing meningioma based on CT and MRI findings. Pathology results were consistent with CG in all three cases. All patients had bone erosion on CT. These skull base CGs did not demonstrate similar MRI features. These lesions were hyperintense, iso-to-hyperintense, and hypointense on T1-weighted MRI, respectively. These CGs were hyperintense in two cases and iso-to-hyperintense in one case on T2-weighted MRI. These lesions either demonstrated central or rim enhancement after gadolinium administration. Skull base CGs that do not arise from the PA demonstrate a broad spectrum of radiographic characteristics on MRI that are not typical of PACG. PMID:26164292

  1. 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

  2. Nasal cavity epithelioid hemangioendothelioma invading the anterior skull base

    PubMed Central

    Ogita, Shogo; Endo, Toshiki; Nomura, Kazuhiro; Ogawa, Takenori; Watanabe, Mika; Higashi, Kenjiro; Katori, Yukio; Tominaga, Teiji

    2016-01-01

    Background: Epithelioid hemangioendothelioma (EHE) is a rare vascular tumor that frequently occurs in soft tissues. Patients suffer from local recurrence and remote metastasis because of its malignant potential. Here, we present a rare case of EHE that originated from nasal cavity and invaded intracranially through the anterior skull base. Case Description: This is a 27-year-old woman who presented a local physician with intermittent epistaxis and a facial pain around her nose. Preoperative studies demonstrated that the tumor invaded into anterior skull base and the dura matter. Therefore, we performed combined skull base and transnasal surgery, which achieved complete resection of the tumor. Postoperative course of the patient was uneventful. No recurrence or distant metastasis was observed in the patient for 2 years following the radical resection. Conclusions: To date, four cases of EHE in the nasal cavity were reported. This is the first case in which EHE demonstrated invasive potentials with intracranial extension. Radical surgical resection plays an important role for better management of invasive paranasal EHE. PMID:27213107

  3. 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

  4. 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

  5. The first skull of the earliest giant panda

    PubMed Central

    Jin, Changzhu; Ciochon, Russell L.; Dong, Wei; Hunt, Robert M.; Liu, Jinyi; Jaeger, Marc; Zhu, Qizhi

    2007-01-01

    Fossils of the giant panda Ailuropoda (Order Carnivora, Family Ursidae) are largely isolated teeth, mandibles, and a few rare skulls, known from the late Pliocene to late Pleistocene in China and Southeast Asia. Much of this material represents a Pleistocene chronospecies, Ailuropoda baconi, an animal larger than the living giant panda, Ailuropoda melanoleuca. The earliest certain record of Ailuropoda is the late Pliocene chronospecies, Ailuropoda microta, smaller than either A. baconi or A. melanoleuca, and previously known only from teeth and a few mandibles from karst caves in south China. Here, we report the discovery of the first skull of A. microta, establishing its cranial anatomy and demonstrating that the specialized cranial and dental adaptations of Ailuropoda for durophagous feeding behavior centered on bamboo were already evident in this late Pliocene species. The skull from Jinyin cave (Guangxi) and dental remains from other karst localities in southeastern China show that Ailuropoda microta occupied south China from ≈2 to 2.4 Myr ago after a marked global climatic deterioration. Dental and basicranial anatomy indicate a less specialized morphology early in the history of the lineage and support derivation of the giant panda from the Miocene Asian ursid Ailurarctos PMID:17578912

  6. 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. PMID:26421478

  7. Macroscopic and roentgenographic anatomy of the skull of the ferret (Mustela putorius furo).

    PubMed

    He, T; Friede, H; Kiliaridis, S

    2002-01-01

    Normal macroscopic and roentgenographic features of the skull of the ferret (Mustela putorius furo) were examined and described. Data were based on a sample of 100 (50 male and 50 female) adult ferrets of known body weight and age. The skull was described macroscopically according to six standard views, i.e. dorsal, lateral, ventral, caudal, cranial and midsagittal. The mandible was described separately. The roentgenographic characteristics of the ferret skull were demonstrated only in lateral and dorsoventral projections. Furthermore, the skull length and width as well as the minimum frontal width were measured, and skull indices were derived from relevant measurements. Sexual dimorphism was examined both morphologically and craniometrically. Besides the common features of a carnivore skull, the ferret skull is relatively elongated and flat with a short facial region. The skulls of adult male ferrets are about 17% longer and 22% wider than those of the females. Significant sexual dimorphism also exists regarding certain skull indices. The general features and some dimensional parameters of the adult ferret skull support the contention that the ferret would be an interesting and workable alternative animal model in craniofacial research. PMID:11831741

  8. 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

  9. 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

  10. Fracture toughness of polyimide films

    NASA Technical Reports Server (NTRS)

    Hinkley, J. A.; Mings, S. L.

    1989-01-01

    Two aromatic polyimides and an aromatic polyamide-imide were tested in single edge notched tension. Fracture toughnesses, normalized to 25 micron film thickness ranged from 1.65 to 5.4 MPa m sup 1/2. LARC-TPI, a thermoplastic polyimide, showed evidence of crazing ahead of a growing crack whereas the other materials formed a shear yielded zone.

  11. 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

  12. 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- ...

  13. Sagittal synostosis: I. Preoperative morphology of the skull.

    PubMed

    Guimarães-Ferreira, José; Gewalli, Fredrik; David, Lisa; Darvann, Tron A; Hermann, Nuno V; Kreiborg, Sven; Friede, Hans; Lauritzen, Claes G K

    2006-01-01

    The aim of this study was to characterise the preoperative morphology of the skull in sagittal synostosis in an objective and quantified way. The shapes of the skulls of 105 patients with isolated premature synostosis of the sagittal suture (SS group) were studied and compared with those of a control group of 72 children with unilateral incomplete cleft lip (UICL). A standardised radiocephalometric technique was used to obtain the images. A modification of a method developed by Kreiborg was used to analyse the radiocephalograms, which included the digitisation of 88 landmarks in the calvaria, skull base, and orbit (42 in the lateral and 46 in the frontal projections), the production of plots of mean shape for each group, and the intergroup comparison of a series of 81 variables (linear distance between selected landmarks, and angles defined by groups of three landmarks). Data from a subgroup of 66 patients aged 5 to 8 months were further compared to age-matched normative data in terms of seven angular and linear calvarial, cranial base and orbital variables. In a comparative analysis of the mean lateral plots, the foreheads of the study group (SS) had a more pronounced anterior slope and were also more convex. The vertex area was located more anteriorly, and was less convex. The occipital curvature was more prominent. Analysis of the mean frontal plots revealed a lack in convexity and lateral projection of the upper parietal regions, as well as a lower location of the line of maximum skull width. Comparison of the mean values of an SS subgroup to age-matched normative data showed a longer (p<0.001) and narrower skull (p<0.001) and a greater interorbital distance (p<0.001). The cranial base angle, the sella to nasion, and sella to basion lengths did not differ significantly. Sagittal synostosis is characterised by an extensive deformity of the cranial vault, with an essentially normal cranial base. The widened interorbital distance is probably related to

  14. 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

  15. 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

  16. Growing Pains (For Parents)

    MedlinePlus

    ... Joints affected by more serious diseases are swollen, red, tender, or warm — the joints of kids having growing pains look normal. Although growing pains often strike in late afternoon or early evening before bed, pain can sometimes wake a sleeping child. The ...

  17. 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.

  18. 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

  19. Lightning injury as a blast injury of skull, brain, and visceral lesions: clinical and experimental evidences.

    PubMed

    Ohashi, M; Hosoda, Y; Fujishiro, Y; Tuyuki, A; Kikuchi, K; Obara, H; Kitagawa, N; Ishikawa, T

    2001-12-01

    The present study attempts to better understand the mechanism of injuries associated with direct lightning strikes. We reviewed the records of 256 individuals struck by lightning between 1965 and 1999, including 56 people who were killed. Basal skull fracture, intracranial haemorrhage, pulmonary haemorrhage, or solid organ rupture was suspected in three men who died. Generally these lesions have been attributed to current flow or falling after being struck. However, examination of surface injuries sustained suggested that the true cause was concussion secondary to blast injury resulting from vaporization of water on the body surface by a surface flashover spark. To investigate this hypothesis, an experimental model of a lightning strike was created in the rat. Saline-soaked blotting paper was used to simulate wet clothing or skin, and an artificial lightning impulse was applied. The resultant lesions were consistent with our hypothesis that the blast was reinforced by the concussive effect of water vaporization. The concordance between the clinical and experimental evidence argues strongly for blast injury as an important source of morbidity and mortality in lightning strikes. PMID:11806503

  20. 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)

  1. Shape and mechanics in thalattosuchian (Crocodylomorpha) skulls: implications for feeding behaviour and niche partitioning

    PubMed Central

    Pierce, S E; Angielczyk, K D; Rayfield, E J

    2009-01-01

    Variation in modern crocodilian and extinct thalattosuchian crocodylomorph skull morphology is only weakly correlated with phylogeny, implying that factors other than evolutionary proximity play important roles in determining crocodile skull shape. To further explore factors potentially influencing morphological differentiation within the Thalattosuchia, we examine teleosaurid and metriorhynchid skull shape variation within a mechanical and dietary context using a combination of finite element modelling and multivariate statistics. Patterns of stress distribution through the skull were found to be very similar in teleosaurid and metriorhynchid species, with stress peaking at the posterior constriction of the snout and around the enlarged supratemporal fenestrae. However, the magnitudes of stresses differ, with metriorhynchids having generally stronger skulls. As with modern crocodilians, a strong linear relationship between skull length and skull strength exists, with short-snouted morphotypes experiencing less stress through the skull than long-snouted morphotypes under equivalent loads. Selection on snout shape related to dietary preference was found to work in orthogonal directions in the two families: diet is associated with snout length in teleosaurids and with snout width in metriorhynchids, suggesting that teleosaurid skulls were adapted for speed of attack and metriorhynchid skulls for force production. Evidence also indicates that morphological and functional differentiation of the skull occurred as a result of dietary preference, allowing closely related sympatric species to exploit a limited environment. Comparisons of the mechanical performance of the thalattosuchian skull with extant crocodilians show that teleosaurids and long-snouted metriorhynchids exhibit stress magnitudes similar to or greater than those of long-snouted modern forms, whereas short-snouted metriorhynchids display stress magnitudes converging on those found in short-snouted modern

  2. [The determination of the type of structural stability of the human skull].

    PubMed

    Zaĭchenko, A A; Anisimova, E A

    1998-01-01

    A total of 819 male and female skulls (frontal sections of 250 of these) were examined by traditional craniometry and MBS-2 microscope in order to assess the variability of morphogeometric parameters of biomechanical resistance of human brain skull and designing its structure typology. The following types of construction resistance of human brain skull (craniotypes) were distinguished: 1) structure resistant; 2) configuration resistant; 3) morphologically resistant; and 4) morphologically unstable. PMID:9567672

  3. The cranial base and calvaria index methods applied to Australian aborigine skulls.

    PubMed

    Göthlin, J H; Gadeholt, G

    1988-11-01

    Cranial base and calvaria indices were calculated on lateral skull radiographs of Australian aborigines, and compared with the values of one mummy, 4 prehistoric (fossil), and modern Scandinavian skulls. The aborigines had thicker calvarian bone and a lower forehead profile than the mummy and the modern skulls, but a higher frontal calvarium than the fossils. The aborigines may developmentally represent a link between prehistoric and modern man (including the mummy). PMID:3234401

  4. 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

  5. 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.

  6. Anaesthesia of the inferior alveolar and lingual nerves following subcondylar fractures of the mandible.

    PubMed

    Politis, Constantinus; Sun, Yi; De Peuter, Bruno; Vandersteen, Marjan

    2013-10-01

    A retrospective chart review of 387 patients with condylar and subcondylar fractures revealed 2 cases of inferior alveolar nerve (IAN) and lingual nerve (LN) anaesthesia following the subcondylar fracture. Only 5 cases have been reported previously. The mechanism of action remains unknown but a review of the literature and an analysis of 120 dry human skulls supported the hypothesis that compression of the mandibular nerve at a high level, close to the foramen ovale, could cause anaesthesia. This complication is rare, because it requires compression at a particular angle. The antero-median angulation of the condyle must be close to the foramen ovale, and the fracture must be a unilaterally displaced fracture. The presence of an enlarged lateral pterygoid plate appeared to enhance the risk of compression. The IAN and LN anaesthesia could be resolved after open reduction of the fracture and IAN and LN anaesthesia constitute a strict indication for an early open fracture reduction. PMID:23453271

  7. 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

  8. 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 ...

  9. 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.

  10. Creating Physical 3D Stereolithograph Models of Brain and Skull

    PubMed Central

    Kelley, Daniel J.; Farhoud, Mohammed; Meyerand, M. Elizabeth; Nelson, David L.; Ramirez, Lincoln F.; Dempsey, Robert J.; Wolf, Alan J.; Alexander, Andrew L.; Davidson, Richard J.

    2007-01-01

    The human brain and skull are three dimensional (3D) anatomical structures with complex surfaces. However, medical images are often two dimensional (2D) and provide incomplete visualization of structural morphology. To overcome this loss in dimension, we developed and validated a freely available, semi-automated pathway to build 3D virtual reality (VR) and hand-held, stereolithograph models. To evaluate whether surface visualization in 3D was more informative than in 2D, undergraduate students (n = 50) used the Gillespie scale to rate 3D VR and physical models of both a living patient-volunteer's brain and the skull of Phineas Gage, a historically famous railroad worker whose misfortune with a projectile tamping iron provided the first evidence of a structure-function relationship in brain. Using our processing pathway, we successfully fabricated human brain and skull replicas and validated that the stereolithograph model preserved the scale of the VR model. Based on the Gillespie ratings, students indicated that the biological utility and quality of visual information at the surface of VR and stereolithograph models were greater than the 2D images from which they were derived. The method we developed is useful to create VR and stereolithograph 3D models from medical images and can be used to model hard or soft tissue in living or preserved specimens. Compared to 2D images, VR and stereolithograph models provide an extra dimension that enhances both the quality of visual information and utility of surface visualization in neuroscience and medicine. PMID:17971879

  11. Endoscopic Endonasal Reconstruction of Skull Base: Repair Protocol.

    PubMed

    Dehdashti, Amir R; Stofko, Douglas; Okun, Jessica; Obourn, Chelsea; Kennedy, Thomas

    2016-06-01

    Background Endoscopic endonasal skull base reconstructions have been associated with postoperative cerebrospinal fluid (CSF) leaks. Objective A repair protocol for endoscopic endonasal skull base reconstruction is presented with the objective of decreasing the overall leak rate. Methods A total of 180 endoscopic endonasal skull base reconstructions were reviewed. Reconstructions were classified I to IV according to the reconstruction method, determined by severity of intraoperatively encountered CSF leaks for types I to III, and planned preoperatively for type IVs, which required nasoseptal flap. Results A total of 11 patients(6%) had postoperative leaks: 0 in type I (0%), 2 in type II (5%), 7 in type III (18%), and 2 (4%) in type IV reconstruction. Type III leak rate was higher than all other reconstructions. Total 31 intraoperative and 16 postoperative lumbar drains were placed. More patients had lumbar drains placed postoperatively for type III and intraoperatively for type IV than all other groups. There were significant overall differences in postoperative CSF leaks and lumbar drain placement between the four reconstruction types. No patient with type III reconstruction and intraoperative lumbar drain had postoperative CSF leak. Conclusions A repair protocol for endoscopic endonasal reconstructions determined by intraoperative CSF leak and preoperative planning minimizes unnecessary repair materials and additional morbidity. Our experience leads to a routine prophylactic lumbar drain placement in all type III leak and reconstructions. We also favor the type III reconstruction for minor intraoperative leaks, and a more generous use of type IV reconstructions in expectation of significant intraoperative CSF leak. The option of rescue flap technique in type III leaks should be strongly considered. PMID:27175324

  12. Primary angiosarcoma of the skull: A rare case report

    PubMed Central

    Chugh, Ashish P.; Gandhoke, Charandeep Singh; Mohite, Anirudha G.; Khedkar, Bhushan V.

    2014-01-01

    Background: Angiosarcomas are rare high grade endothelial tumors characterized by rapidly proliferating anaplastic cells derived from blood vessels and lining irregular blood filled spaces. Primary neoplasms of the skull are rare, representing 2.6% of primary neoplasms of bone. Primary malignant neoplasms of the skull are even rarer, accounting for only 0.8% of primary malignant neoplasms of bone. Case Description: We report a 32-year-old female who presented with right parieto-occipital swelling, which gradually increased in size. Radiology was suggestive of a calvarial soft tissue lesion in the right parieto-occipital region with destruction of the adjacent parieto-occipital bone with intracranial extra-axial extension. Complete surgical excision of the calvarial lesion was done under general anesthesia. Postoperative computed tomography (CT) scan of brain (plain and with contrast) showed complete excision of the tumor mass. Histopathological diagnosis was consistent with ‘an angiosarcoma of the skull’. On immunohistochemistry, the atypical endothelial cells were highlighted by CD34, CD31, and factor VIII-related antigen. The patient received adjuvant radiotherapy to the tumor bed. Conclusion: Primary angiosarcoma of the skull is a rare tumor with less than 20 cases reported worldwide till date. The treatment should include complete surgical excision with a wide bony margin followed by adjuvant radiotherapy, which in our case has given a good locoregional control even at the end of 2 years. However, these patients should be followed up with repeated scans yearly to rule out locoregional as well as distant recurrence. PMID:25024892

  13. 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 ...

  14. Hydraulic fracturing-1

    SciTech Connect

    Not Available

    1990-01-01

    This book contains papers on hydraulic fracturing. Topics covered include: An overview of recent advances in hydraulic fracturing technology; Containment of massive hydraulic fracture; and Fracturing with a high-strength proppant.

  15. [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. PMID:27029129

  16. Expanded Endoscopic Endonasal Approaches to Skull Base Meningiomas

    PubMed Central

    Prosser, J. Drew; Vender, John R.; Alleyne, Cargill H.; Solares, C. Arturo

    2012-01-01

    Anterior cranial base meningiomas have traditionally been addressed via frontal or frontolateral approaches. However, with the advances in endoscopic endonasal treatment of pituitary lesions, the transphenoidal approach is being expanded to address lesions of the petrous ridge, anterior clinoid, clivus, sella, parasellar region, tuberculum, planum, olfactory groove, and crista galli regions. The expanded endoscopic endonasal approach (EEEA) has the advantage of limiting brain retraction and resultant brain edema, as well as minimizing manipulation of neural structures. Herein, we describe the techniques of transclival, transphenoidal, transplanum, and transcribiform resections of anterior skull base meningiomas. Selected cases are presented. PMID:23730542

  17. A checklist for endonasal transsphenoidal anterior skull base surgery.

    PubMed

    Laws, Edward R; Wong, Judith M; Smith, Timothy R; de Los Reyes, Kenneth; Aglio, Linda S; Thorne, Alison J; Cote, David J; Esposito, Felice; Cappabianca, Paolo; Gawande, Atul

    2016-06-01

    OBJECT Approximately 250 million surgical procedures are performed annually worldwide, and data suggest that major complications occur in 3%-17% of them. Many of these complications can be classified as avoidable, and previous studies have demonstrated that preoperative checklists improve operating room teamwork and decrease complication rates. Although the authors' institution has instituted a general preoperative "time-out" designed to streamline communication, flatten vertical authority gradients, and decrease procedural errors, there is no specific checklist for transnasal transsphenoidal anterior skull base surgery, with or without endoscopy. Such minimally invasive cranial surgery uses a completely different conceptual approach, set-up, instrumentation, and operative procedure. Therefore, it can be associated with different types of complications as compared with open cranial surgery. The authors hypothesized that a detailed, procedure-specific, preoperative checklist would be useful to reduce errors, improve outcomes, decrease delays, and maximize both teambuilding and operational efficiency. Thus, the object of this study was to develop such a checklist for endonasal transsphenoidal anterior skull base surgery. METHODS An expert panel was convened that consisted of all members of the typical surgical team for transsphenoidal endoscopic cases: neurosurgeons, anesthesiologists, circulating nurses, scrub technicians, surgical operations managers, and technical assistants. Beginning with a general checklist, procedure-specific items were added and categorized into 4 pauses: Anesthesia Pause, Surgical Pause, Equipment Pause, and Closure Pause. RESULTS The final endonasal transsphenoidal anterior skull base surgery checklist is composed of the following 4 pauses. The Anesthesia Pause consists of patient identification, diagnosis, pertinent laboratory studies, medications, surgical preparation, patient positioning, intravenous/arterial access, fluid management

  18. Development of a fracture network: a block and springs model

    SciTech Connect

    Ferer, M.V.; Jozwick, A.; Smith, D.H.

    2008-03-01

    Since flow in fractured reservoirs is significantly enhanced by clusters of inter-connecting fractures, it's important to understand their inter-connectedness. In these fractured reservoirs, one often finds two sets of fractures due to two separate geologic events. We have developed a blocks and springs model to study how the second generation fractures intersect the first generation of. We find a percolation-like transition where the cluster size grows with increasing strain leading to system-spanning fractal clusters. Increasing the thickness of the layer being fractured leads to sparser system-spanning fracture clusters with smaller fractal dimension. We have studied how the thickness of the layer affects the fractal character of the fracture clusters as well as their number distribution, and the correlations within the large fracture cluster.

  19. 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

  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. PMID:26103927

  1. Hydraulic Fracturing in Saturated Cohesionless Materials

    NASA Astrophysics Data System (ADS)

    Germanovich, L. N.; Hurt, R. S.; Huang, H.

    2007-12-01

    Based on the developed experimental techniques, hydraulic fracturing in particulate materials has been directly observed in the laboratory. As a result, we suggested several mechanisms of hydraulic fracturing in particulate materials and determined relevant scaling relationships (e.g., the interplay between elastic and plastic processes). While the ongoing work is likely to change at least some conclusions, it is important that the results reported in this work appear to form the framework for modeling and, perhaps, even for (qualitative) interpretation of field data. The observed fracture geometry and the measured pressure injection curves suggest that hydraulic fracturing occurs in soft sediments in the following sequence: (i) cavity expansion, (ii) fracture front initiation, and (iii) propagation of the developed fracture. Our experiments show that liquid can indeed propagate as a crack-like feature when injected into cohesionless saturated materials. Laboratory observations suggest that at the initial stage, the cavity expansion process ends with fracture initiation. Sometimes, the growing fracture resembles penetration of one movable material into another less movable material, which may be a manifestation of the Taylor-like instability. An important conclusion of our work is that all parts of the cohesionless particulate material (including the tip zone of hydraulic fracture) are likely to be in compression. The compressive stress state is an important characteristic of hydraulic fracturing in particulate materials with low, or no, cohesion (such as were used in our experiments). At present, two kinematic mechanisms of fracture propagation, consistent with the compressive stress regime, can be offered. The first mechanism is based on shear bands propagating ahead of the tip of an open fracture. The second is based on the tensile strain ahead of the fracture tip and reduction of the effective stresses to zero within the leak-off zone. Additionally, an

  2. 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

  3. 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

  4. 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.

  5. 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

  6. 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.

  7. 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. PMID:23257563

  8. 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

  9. Osteoradionecrosis of the skull after radiation therapy for invasive carcinoma.

    PubMed

    Nguyen, Michaela T; Billington, Alicia; Habal, Mutaz B

    2011-09-01

    Osteoradionecrosis (ORN) of the skull is a rare but fatal complication of radiation therapy for the treatment of head and neck malignancies. The pathogenesis of ORN follows the "3Hs Theory" proposed by Marx (J Oral Maxillofac Surg 1983;41:283-288) in which radiation induces tissue injury by causing vessel thrombosis (hypovascularity), which leads to hypoxia, and results in cell death of the skin and the underlying structure of the bony element (hypocellularity) including the deep visceral structures. This note details a patient with severe and extensive ORN of the parietooccipital region of the skull because of a large dose of radiation therapy for the treatment of an invasive basal cell carcinoma of the scalp. The patient's condition was further complicated by an extensive infection with methicillin-resistant Staphylococcus aureus, which leads to meningitis and cerebral edema as well as cerebritis. The patient was successfully treated with interdisciplinary medical and surgical aggressive therapy and radical procedures involving 4 separate trips to the operating room for an 18-month period. Success was achieved because of early clinical diagnosis of ORN, aggressive eradication of infected and necrotic tissues including the brain, and restoration of functioning and viable tissues through the use of local flaps to change an open wound to a closed wound. PMID:21959411

  10. 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. PMID:19106500

  11. 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…

  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. Are more diverse parts of the mammalian skull more labile?

    PubMed

    Linde-Medina, Marta; Boughner, Julia C; Santana, Sharlene E; Diogo, Rui

    2016-04-01

    Morphological variation is unevenly distributed within the mammalian skull; some of its parts have diversified more than others. It is commonly thought that this pattern of variation is mainly the result of the structural organization of the skull, as defined by the pattern and magnitude of trait covariation. Patterns of trait covariation can facilitate morphological diversification if they are aligned in the direction of selection, or these patterns can constrain diversification if oriented in a different direction. Within this theoretical framework, it is thought that more variable parts possess patterns of trait covariation that made them more capable of evolutionary change, that is, are more labile. However, differences in the degree of morphological variation among skull traits could arise despite variation in trait lability if, for example, some traits have evolved at a different rate and/or undergone stabilizing selection. Here, we test these hypotheses in the mammalian skull using 2D geometric morphometrics to quantify skull shape and estimating constraint, rates of evolution, and lability. Contrary to the expectations, more variable parts of the skull across mammalian species are less capable of evolutionary change than are less variable skull parts. Our results suggest that patterns of morphological variation in the skull could result from differences in rate of evolution and stabilizing selection. PMID:27069580

  14. 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

  15. Fluid-driven multiple fracture growth from a permeable bedding plane intersected by an ascending hydraulic fracture

    NASA Astrophysics Data System (ADS)

    Zhang, Xi; Jeffrey, Robert G.

    2012-12-01

    In bedded sedimentary rocks, the energy for spontaneous growth of multiple vertical fractures from a bedding plane may be provided by an overpressurized sublayer fracture that connects a fluid source to the bedding plane. In this paper, using our coupled deformation and flow model, we study the processes and mechanisms involved in the formation and interaction of closely space fractures from preexisting flaws or starter fractures located along the bedding plane. Fracture growth from multiple flaws can be convergent, parallel or divergent, depending on the factors like contrasts in moduli and far-field stresses, flaw sizes and locations, and initial bed conductivity, fluid viscosity, and injection rate, as well as time. The results presented here have been obtained for conditions where fluid viscous dissipation is dominant, in contrast to other results available in literature based on uniform pressure assumption equivalent to use of an inviscid fluid. It is demonstrated that the earlier a hydraulic fracture starts to extend, the more likely it is to become the primary fracture in a system of closely spaced fractures. The fracture closest to the fluid source typically grows faster as a result of a higher pressure level because viscous dissipation results in a decrease in pressure with distance from the fluid source. But its development does not completely inhibit the growth of other hydraulic fractures. Simultaneous growth of closely spaced fractures is supported by the local stress and energetic analyses, and the fracture distance can be very small. Their length to spacing ratio is accordingly much larger than that predicted previously. Under certain circumstances, a longer and more permeable fracture may grow to a greater extent than a shorter fracture closer to the fluid source, which may grow toward and merge with the longer fracture to create fracture clusters adjacent to a bedding plane.

  16. 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)

  17. 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…

  18. 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…

  19. Growing Up In Appalachia.

    ERIC Educational Resources Information Center

    Reed, Judith

    1981-01-01

    Offers a glimpse of a Smithsonian Institution Traveling Exhibition of 80 photographs and selected writings by first through eighth grade children growing up in Letcher County, Kentucky. Children were guided by an artist-in-residence sponsored by the Kentucky Arts Commission and Appalshop, a multimedia cooperative. (Author/RH)

  20. 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)

  1. 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)

  2. Growing a Nurturing Classroom

    ERIC Educational Resources Information Center

    Boorn, Clare; Dunn, Paula Hopkins; Page, Claire

    2010-01-01

    "Growing a nurturing classroom" is an awareness training programme presented by educational psychologists in Leicestershire for professionals working in primary schools with the aim of promoting an optimal environment for learning and emotional well-being. The training helps primary school staff to take a holistic approach to education; see…

  3. Skull base metastasis from papillary thyroid carcinoma: a report of three cases

    PubMed Central

    Tunio, Mutahir A; Al Asiri, Mushabbab; Al-Qahtani, Khalid Hussain; Aldandan, Sadiq; Riaz, Khalid; Bayoumi, Yasser

    2015-01-01

    Skull base metastasis from differentiated thyroid carcinoma, including papillary and follicular thyroid carcinoma, is a rare manifestation. Herein, we present three cases of skull base metastasis of papillary thyroid carcinoma. The mean age of the patients was 68.6 (65–74) years, and the mean interval between initial diagnosis and skull base metastasis was 56.3 (28–89) months. Cranial nerve palsies were seen in all patients. Intensity modulated radiation therapy to deliver 6,000–6,600 cGy to the skull base metastasis was given to all patients, in addition to partial resection in one patient. At the time of last follow-up, all skull base metastases were well controlled. PMID:26203287

  4. 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.

  5. Photoacoustic tomography through a whole adult human skull with a photon recycler

    NASA Astrophysics Data System (ADS)

    Nie, Liming; Cai, Xin; Maslov, Konstantin; Garcia-Uribe, Alejandro; Anastasio, Mark A.; Wang, Lihong V.

    2012-11-01

    Photoacoustic tomography (PAT) of the human brain is challenging due to the fact that the skull strongly absorbs and scatters light, and attenuates and distorts ultrasound as well. For the first time, we demonstrated the feasibility of PAT through a whole adult human skull. A photon recycler (PR) was built to increase light transmittance through the skull. Both a graphite target and a canine brain were imaged through the skull. Use of the PR was found to improve the photoacoustic signal-to-noise ratio by a factor of 2.4. In addition, subtraction of photoacoustic signals that arise from light absorption within the skull significantly improved the contrast of the target. Our results indicate that PAT can potentially be applied to in vivo human brain imaging.

  6. 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

  7. 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.

  8. Divergent effects of obesity on fragility fractures

    PubMed Central

    Caffarelli, Carla; Alessi, Chiara; Nuti, Ranuccio; Gonnelli, Stefano

    2014-01-01

    Obesity was commonly thought to be advantageous for maintaining healthy bones due to the higher bone mineral density observed in overweight individuals. However, several recent studies have challenged the widespread belief that obesity is protective against fracture and have suggested that obesity is a risk factor for certain fractures. The effect of obesity on fracture risk is site-dependent, the risk being increased for some fractures (humerus, ankle, upper arm) and decreased for others (hip, pelvis, wrist). Moreover, the relationship between obesity and fracture may also vary by sex, age, and ethnicity. Risk factors for fracture in obese individuals appear to be similar to those in nonobese populations, although patterns of falling are particularly important in the obese. Research is needed to determine if and how visceral fat and metabolic complications of obesity (type 2 diabetes mellitus, insulin resistance, chronic inflammation, etc) are causally associated with bone status and fragility fracture risk. Vitamin D deficiency and hypogonadism may also influence fracture risk in obese individuals. Fracture algorithms such as FRAX® might be expected to underestimate fracture probability. Studies specifically designed to evaluate the antifracture efficacy of different drugs in obese patients are not available; however, literature data may suggest that in obese patients higher doses of the bisphosphonates might be required in order to maintain efficacy against nonvertebral fractures. Therefore, the search for better methods for the identification of fragility fracture risk in the growing population of adult and elderly subjects with obesity might be considered a clinical priority which could improve the prevention of fracture in obese individuals. PMID:25284996

  9. 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.

  10. 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.

  11. How to grow tomatoes.

    PubMed

    Kimura, Seisuke; Sinha, Neelima

    2008-01-01

    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. PMID:21356721

  12. 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…

  13. Intraoperative Cranial Nerve Monitoring During Posterior Skull Base Surgery

    PubMed Central

    Kartush, Jack M.; LaRouere, Michael J.; Graham, Malcolm D.; Bouchard, Kenneth R.; Audet, Blaise V.

    1991-01-01

    Intraoperative monitoring of neurophysiologic function is rapidly evolving as an important adjunct during skull base surgery to reduce the incidence of neurologic deficit. Facial nerve monitoring is an excellent model, since electrical and mechanical evoked potentials can be directly presented to the surgeon in real-time through an acoustic loudspeaker display. The lower cranial nerves may also be monitored using similar electromyographic techniques. Auditory system monitoring is more difficult due to the low amplitude response that requires averaging and filtering to extract the evoked potential. In conjunction with auditory monitoring, improved hearing preservation may be further enhanced by concomitant facial nerve monitoring, since the surgeon is alerted to traumatic manipulations that may affect both facial and cochlear nerves. Techniques and interpretative issues are presented to maximize the efficacy and safety of cranial nerve monitoring. ImagesFigure 1Figure 2Figure 3Figure 5 PMID:17170827

  14. Review of photon and proton radiotherapy for skull base tumours.

    PubMed

    Fossati, Piero; Vavassori, Andrea; Deantonio, Letizia; Ferrara, Eleonora; Krengli, Marco; Orecchia, Roberto

    2016-01-01

    An extremely large variety of benign and malignant tumours occur at skull base; these tumour lesions are in the proximity to structures deputed to relevant physiologic functions, limiting extensive surgical approaches to this body district. Most recent progresses of surgery and radiotherapy have allowed to improve local control with acceptable rates of side effects. Various photon radiotherapy techniques are employed, including 3-dimensional conformal radiotherapy, intensity modulated radiotherapy (IMRT), stereotactic radiotherapy (SRT) and brachytherapy that is manly limited to the treatment of primary or recurrent nasopharyngeal carcinoma. Proton beam radiotherapy is also extensively used thanks to its physical characteristics. Our review, focusing in particular on meningioma, chordoma, and chondrosarcoma, suggests that proton therapy plays a major role in the treatment of malignant tumours whereas photon therapy still plays a relevant role in the treatment of benign tumour lesions. PMID:27330419

  15. Distal humerus fractures: a review of current therapy concepts.

    PubMed

    Amir, Steinitz; Jannis, Sailer; Daniel, Rikli

    2016-06-01

    Fractures of the distal humerus in the adult comprise approximately one third of all humeral fractures. Successful management of distal humerus fractures depends on correct reduction of the fracture, reconstruction of the articular surface if needed, stability and rigidity of the fixation, and appropriate rehabilitation. In this review, we evaluated the available literature and highlighted current therapy concepts. We assessed the evolution of internal fixation and elbow arthroplasty focusing on the established surgical approaches against the background of a growing incidence of distal humeral fractures in an aging patient population. Therefore evaluating the aspect and influence of age-dependent comorbidities like osteoporosis on successful treatment. PMID:27039395

  16. 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.

  17. 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

  18. 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

  19. A noninvasive method for focused ultrasound surgery through the human skull

    NASA Astrophysics Data System (ADS)

    Clement, Gregory; Hynynen, Kullervo

    2002-05-01

    A technique for focusing ultrasound through the skull bone is described and verified. The approach is based on a layered wave-vector-frequency domain model, which simulates ultrasound propagation through the skull bone using input from CT scans of the head. The algorithm calculates the driving phase of each element in a transducer array in order to maximize the signal at the intended focus. This approach is tested on ten ex vivo human skulls using a 500-element hemispherical array operated at 0.74 MHz. A stereotaxic reference frame is affixed to the skulls in order to provide accurate registration between the CT images and the transducer. The focal quality is assessed with a hydrophone placed inside of the skull. In each trial the phase correction algorithm successfully restored the focus inside the skull in a location within 1 mm from the intended focal point. Focusing at high powers (>800-W electrical input) is demonstrated using a brain phantom placed inside a skull. The results demonstrate the feasibility of using the method for completely noninvasive ultrasound brain surgery and therapy.

  20. 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

  1. 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.

  2. A continuous point measure for quantifying skull deformation in medical diagnostics.

    PubMed

    Jelinek, Herbert F; Strachan, Ben; O'Connor, Bridget; Khandoker, Ahsan

    2014-06-01

    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

  3. Estimation of in vivo brain-to-skull conductivity ratio in humans

    NASA Astrophysics Data System (ADS)

    Zhang, Yingchun; van Drongelen, Wim; He, Bin

    2006-11-01

    The electrical conductivity value of the human skull is important for biophysics research of the brain. In the present study, the human brain-to-skull conductivity ratio was estimated through in vivo experiments utilizing intracranial electrical stimulation in two epilepsy patients. A realistic geometry inhomogeneous head model including the implanted silastic grids was constructed with the aid of the finite element method, and used to estimate the conductivity ratio. Averaging over 49 sets of measurements, the mean value and standard deviation of the brain-to-skull conductivity ratio were found to be 18.7 and 2.1, respectively.

  4. 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

  5. Radial head fracture - aftercare

    MedlinePlus

    Elbow fracture - radial head - aftercare ... the radius bone, just below your elbow. A fracture is a break in your bone. The most common cause of a radial head fracture is falling with an outstretched arm.

  6. Hand fracture - aftercare

    MedlinePlus

    ... this page: //medlineplus.gov/ency/patientinstructions/000552.htm Hand fracture - aftercare To use the sharing features on ... need to be repaired with surgery. Types of hand fractures Your fracture may be in one of ...

  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. 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.

  10. 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.

  11. Cavernous hemangioma of the skull presenting with subdural hematoma. Case report.

    PubMed

    Gottfried, Oren N; Gluf, Wayne M; Schmidt, Meic H

    2004-10-15

    Cavernous hemangioma of the calvaria is a very rare disease, and patients usually present with headaches or a visible skull deformity. Few reports of patients presenting with intradiploic or epidural hemorrhages are found in the literature. No case of an intradural hemorrhage from a cavernous hemangioma of the skull has been reported to date. The authors present the case of a 50-year-old man in whom a symptomatic subdural hematoma (SDH) resulting from a cavernous hemangioma of the calvaria had hemorrhaged and eroded through the inner table of the skull and dura mater. The patient underwent surgery for evacuation of the SDH and resection of the calvarial lesion. Postoperatively, the patient experienced immediate relief of his symptoms and had no clinical or radiological recurrence. Calvarial cavernous hemangiomas should be considered in the differential diagnosis of nontraumatic SDHs. Additionally, skull lesions that present with intracranial hemorrhages must be identified and resected at the time of hematoma evacuation to prevent recurrences. PMID:15633993

  12. 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

  13. Development of secondary skull sarcoma after treatment for childhood acute myeloid leukemia.

    PubMed

    Ohno, Makoto; Narita, Yoshitaka; Miyakita, Yasuji; Okita, Yoshiko; Kayama, Takamasa; Shibui, Soichiro

    2012-12-01

    Secondary cancer is a serious late complication in childhood leukemia survivors. Here, we report a case of secondary skull sarcoma developing after treatment for childhood acute myeloid leukemia, including bone marrow transplantation (BMT). This patient had breast cancer 1 year before treatment for the skull sarcoma. The patient underwent macroscopic total removal of the skull tumor with bone margin with postoperative radiation therapy and did not develop tumor recurrence for 25 months. Our patient's experience suggests that survivors of childhood leukemia are at risk of developing skull sarcoma and that multi-agent chemotherapy, including anthracycline, TBI used as conditioning for BMT, and development of GVHD, are possible risk factors. Considering the possibility of multiple secondary malignancies in such patients, careful long-term follow up is mandatory. PMID:22897987

  14. 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.

  15. [Methods of making the plaster copies of skulls for the medical and criminalistic identification of individuals].

    PubMed

    Zviagin, V N; Berezovskiĭ, M E; Aunapu, S A

    2003-01-01

    A possibility was studied to use the plaster copies of skulls in the forensic medical identification of personality by applying the craniofacial method. No dependence was found between the plaster casts and the moulding types. Differences between the same craniometric sizes in the skull and in its cast are of an incidental nature. Such incidental deviation is related with an accuracy of determining the localization of craniometric points and with an instrumental precision of measuring devices. The necessity is substantiated that, while making a craniofacial examination, it is necessary to mark all anthropometric points in the skull cast, with the original being a control. The use of a plaster skull cast is possible in those cases, when the burial of the remains must be done in full. PMID:12866229

  16. Thanatophoric dysplasia type 1 with cloverleaf skull in a dichorionic twin.

    PubMed

    Salinas-Torres, V M

    2015-01-01

    Here is reported for the first time, a case of thanatophoric dysplasia type 1 with cloverleaf skull in a (Mexican) dichorionic female twin. The patient's main clinical and radiographic findings included severe limb shortening, narrow thorax shape; short ribs, marked platyspondyly, curved short femurs, and a cloverleaf skull. The female twin sib had normal growth parameters and phenotypic appearance. According to the literature, cloverleaf skull in thanatophoric dysplasia type 1 is rare, even more so in dichorionic twins. Moreover, the present observation confirms that thanatophoric dysplasia type 1 patients may show phenotypic heterogeneity related to cloverleaf skull and other congenital anomalies. Therefore, a careful family history along with clinical, radiological, and molecular investigations is suggested, in order to achieve an accurate parental counseling for thanatophoric dysplasia. PMID:26043509

  17. 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. PMID:22372748

  18. 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

  19. 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

  20. 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

  1. 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.

  2. 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

  3. Beyond the middle ear: endoscopic surgical anatomy and approaches to inner ear and lateral skull base.

    PubMed

    Presutti, Livio; Nogueira, João Flávio; Alicandri-Ciufelli, Matteo; Marchioni, Daniele

    2013-04-01

    Currently, the main application of endoscopic surgery relies on the middle ear cholesteatoma surgical treatment. However, in the natural evolution of the technique there are the steps toward of lateral skull base surgery and treatment of pathologic conditions of pertous bone. The endoscopic approaches to lateral skull base are (1) a transcanal exclusively endoscopic approach or (2) combined approaches (microscopic endoscope-assisted), including transotic, infralabyrinthine, and suprameatal translabyrinthine. PMID:23566905

  4. 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

  5. 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

  6. 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

  7. 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.

  8. Volumetric-modulated arc radiotherapy for skull-base and non-skull-base head and neck cancer: a treatment planning comparison with fixed Beam IMRT.

    PubMed

    Chen, J; Mok, E; Wang, L; Chen, C; Le, Q-T

    2013-02-01

    The purpose of this study is to compare the dose distribution, monitor units (MUs) and radiation delivery time between volumetric-modulated arc (VMAT) and fix-beam intensity modulated radiotherapy (FB-IMRT) in skull-base and non-skull-base head and neck cancer (HNC). CT datasets of 8 skull-base and 7 non-skull-base HNC were identified. IMRT and VMAT plans were generated. The prescription dose ranged 45-70 Gy (1.8-2.2 Gy/fraction). The VMAT delivery time was measured when these plans were delivered to the patients. The FB-IMRT delivery time was generated on a phantom. Comparison of dose-volume histogram data, MUs, and delivery times was performed using T-test. Our results show that both plans yield similar target volume coverage, homogeneity, and conformity. In skull-base cases, compared to FB-IMRT, VMAT generated significantly smaller hot-spot inside PTV (2.0% vs. 4.5%, p = 0.031), lower maximum chiasm dose (32 ± 11 Gy vs. 41 ± 15 Gy, p = 0.026), lower ipsilateral temporal-mandibular joint dose (D33: 41.4 Gy vs. 46.1 Gy, p = 0.016), lower mean ipsilateral middle ear dose (43 ± 9 Gy vs. 38 ± 10 Gy, p = 0.020) and a trend for lower optic nerve, temporal lobe, parotid, and oral cavity dose. In non-skull-base cases, doses to normal tissues were similar between the two plans. There was a reduction of 70% in MUs (486 ± 95 vs. 1614 ± 493, p < 0.001) and 73% in delivery times (3.0 ± 0.6 vs. 11.0 ± 3.3 min, p < 0.001) favoring VMAT. We conclude that VMAT appears to spare more normal tissues from high radiation dose for the tested skull-base tumors. Dosimetrically, both approaches were equivalent for non-skull-base tumor with VMAT using fewer MUs and shorter delivery time. PMID:22905805

  9. 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

  10. Automatic Sex Determination of Skulls Based on a Statistical Shape Model

    PubMed Central

    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. PMID:24312134

  11. 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.

  12. 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

  13. 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.

  14. 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.

  15. A cephalometric study of skulls from the Bahriyah oasis

    PubMed Central

    Zaki, Moushira Erfan; Soliman, Muhammad Al-Tohamy; El-Bassyouni, Hala T.

    2012-01-01

    Objectives: To determine the craniofacial characteristics of crania from the Bahariyah oasis dating from the Greco-Roman period and to compare their cephalometric traits with other ancient Egyptian samples from various time periods and to evaluate sexual dimorphism. Materials and Methods: The sample comprised 149 skulls (90 males and 59 females), belonging to the Greco-Roman (332 B.C. – 395 A.D.). Lateral and postero-anterior cephalograms were taken. Sixteen linear measurements were analyzed and six indices were calculated. Results: Significant differences were found between males and females almost in all measurements. All male measurements were greater than those of the females. The study shows notable differences in the craniofacial parameters of the present sample as compared to other ancient Egyptians from various periods and from various geographical areas. Conclusion: The present study suggests that the studied crania from Bahriyah oasis had a specific craniometric phenotype, which is distinguished from other Egyptian samples from different periods, suggesting some migration could have occurred along the Egyptian Nile Valley over various times. PMID:23741149

  16. 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

  17. Ecomorphology of the eyes and skull in zooplanktivorous labrid fishes

    NASA Astrophysics Data System (ADS)

    Schmitz, L.; Wainwright, P. C.

    2011-06-01

    Zooplanktivory is one of the most distinct trophic niches in coral reef fishes, and a number of skull traits are widely recognized as being adaptations for feeding in midwater on small planktonic prey. Previous studies have concluded that zooplanktivores have larger eyes for sharper visual acuity, reduced mouth structures to match small prey sizes, and longer gill rakers to help retain captured prey. We tested these three traditional hypotheses plus two novel adaptive hypotheses in labrids, a clade of very diverse coral reef fishes that show multiple independent evolutionary origins of zooplanktivory. Using phylogenetic comparative methods with a data set from 21 species, we failed to find larger eyes in three independent transitions to zooplanktivory. Instead, an impression of large eyes may be caused by a size reduction of the anterior facial region. However, two zooplanktivores ( Clepticus parrae and Halichoeres pictus) possess several features interpreted as adaptations to zooplankton feeding, namely large lens diameters relative to eye axial length, round pupil shape, and long gill rakers. The third zooplanktivore in our analysis, Cirrhilabrus solorensis, lacks all above features. It remains unclear whether Cirrhilabrus shows optical specializations for capturing planktonic prey. Our results support the prediction that increased visual acuity is adaptive for zooplanktivory, but in labrids increases in eye size are apparently not part of the evolutionary response.

  18. 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

  19. 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

  20. 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

  1. Growing vortex patches

    NASA Astrophysics Data System (ADS)

    Crowdy, Darren; Marshall, Jonathan

    2004-08-01

    This paper demonstrates that two well-known equilibrium solutions of the Euler equations—the corotating point vortex pair and the Rankine vortex—are connected by a continuous branch of exact solutions. The central idea is to "grow" new vortex patches at two stagnation points that exist in the frame of reference of the corotating point vortex pair. This is done by generalizing a mathematical technique for constructing vortex equilibria first presented by Crowdy [D. G. Crowdy, "A class of exact multipolar vortices," Phys. Fluids 11, 2556 (1999)]. The solutions exhibit several interesting features, including the merging of two separate vortex patches via the development of touching cusps. Numerical contour dynamics methods are used to verify the mathematical solutions and reveal them to be robust structures. The general issue of how simple vortex equilibria can be continued continuously to more complicated ones with very different vortical topologies is discussed. The solutions are examples of exact solutions of the Euler equations involving multiple interacting vortex patches.

  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. PMID:25286303

  3. Fracture channel waves

    SciTech Connect

    Nihei, K.T.; Yi, W.; Myer, L.R.; Cook, N.G.; Schoenberg, M.

    1999-03-01

    The properties of guided waves which propagate between two parallel fractures are examined. Plane wave analysis is used to obtain a dispersion equation for the velocities of fracture channel waves. Analysis of this equation demonstrates that parallel fractures form an elastic waveguide that supports two symmetric and two antisymmetric dispersive Rayleigh channel waves, each with particle motions and velocities that are sensitive to the normal and tangential stiffnesses of the fractures. These fracture channel waves degenerate to shear waves when the fracture stiffnesses are large, to Rayleigh waves and Rayleigh-Lamb plate waves when the fracture stiffnesses are low, and to fracture interface waves when the fractures are either very closely spaced or widely separated. For intermediate fracture stiffnesses typical of fractured rock masses, fracture channel waves are dispersive and exhibit moderate to strong localization of guided wave energy between the fractures. The existence of these waves is examined using laboratory acoustic measurements on a fractured marble plate. This experiment confirms the distinct particle motion of the fundamental antisymmetric fracture channel wave (A{sub 0} mode) and demonstrates the ease with which a fracture channel wave can be generated and detected. {copyright} 1999 American Geophysical Union

  4. A child with bone fractures and dysmorphic features: remember of pycnodysostosis and craniosynostosis.

    PubMed

    Berenguer, Alberto; Freitas, António Pedro; Ferreira, Gomes; Nunes, José Luis

    2012-01-01

    Accidental bony injuries are common in children. Children may also present with bony injuries following non-accidental injuries. Pathological fractures, though extremely rare, are an important entity and constitute fractures that occur in abnormal bones, usually after minor trauma. Pycnodysostosis is a rare skeletal dysplasia characterised by a clinical phenotype that includes short stature, skull deformities, osteosclerosis, acroosteolysis and bone fragility. Often the disease is diagnosed at an early age as a result of the investigation of short stature. However, the diagnosis is sometimes delayed and must be considered in any child with a history of recurrent or multiple bone fractures and dysmorphic features. The purpose of this report is to describe the clinical, radiological and genetic issues of a 9-year-old girl with a long history of multiple bone fractures. She had been subjected to safeguarding investigations previously and was identified to have dysmorphic features diagnosed as pycnodysostosis associated with craniosynostosis. PMID:23175007

  5. 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

  6. 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

  7. 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

  8. 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

  9. 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

  10. The First AO Classification System for Fractures of the Craniomaxillofacial Skeleton: Rationale, Methodological Background, Developmental Process, and Objectives.

    PubMed

    Audigé, Laurent; Cornelius, Carl-Peter; Di Ieva, Antonio; Prein, Joachim

    2014-12-01

    Validated trauma classification systems are the sole means to provide the basis for reliable documentation and evaluation of patient care, which will open the gateway to evidence-based procedures and healthcare in the coming years. With the support of AO Investigation and Documentation, a classification group was established to develop and evaluate a comprehensive classification system for craniomaxillofacial (CMF) fractures. Blueprints for fracture classification in the major constituents of the human skull were drafted and then evaluated by a multispecialty group of experienced CMF surgeons and a radiologist in a structured process during iterative agreement sessions. At each session, surgeons independently classified the radiological imaging of up to 150 consecutive cases with CMF fractures. During subsequent review meetings, all discrepancies in the classification outcome were critically appraised for clarification and improvement until consensus was reached. The resulting CMF classification system is structured in a hierarchical fashion with three levels of increasing complexity. The most elementary level 1 simply distinguishes four fracture locations within the skull: mandible (code 91), midface (code 92), skull base (code 93), and cranial vault (code 94). Levels 2 and 3 focus on further defining the fracture locations and for fracture morphology, achieving an almost individual mapping of the fracture pattern. This introductory article describes the rationale for the comprehensive AO CMF classification system, discusses the methodological framework, and provides insight into the experiences and interactions during the evaluation process within the core groups. The details of this system in terms of anatomy and levels are presented in a series of focused tutorials illustrated with case examples in this special issue of the Journal. PMID:25489387

  11. The First AO Classification System for Fractures of the Craniomaxillofacial Skeleton: Rationale, Methodological Background, Developmental Process, and Objectives

    PubMed Central

    Audigé, Laurent; Cornelius, Carl-Peter; Ieva, Antonio Di; Prein, Joachim

    2014-01-01

    Validated trauma classification systems are the sole means to provide the basis for reliable documentation and evaluation of patient care, which will open the gateway to evidence-based procedures and healthcare in the coming years. With the support of AO Investigation and Documentation, a classification group was established to develop and evaluate a comprehensive classification system for craniomaxillofacial (CMF) fractures. Blueprints for fracture classification in the major constituents of the human skull were drafted and then evaluated by a multispecialty group of experienced CMF surgeons and a radiologist in a structured process during iterative agreement sessions. At each session, surgeons independently classified the radiological imaging of up to 150 consecutive cases with CMF fractures. During subsequent review meetings, all discrepancies in the classification outcome were critically appraised for clarification and improvement until consensus was reached. The resulting CMF classification system is structured in a hierarchical fashion with three levels of increasing complexity. The most elementary level 1 simply distinguishes four fracture locations within the skull: mandible (code 91), midface (code 92), skull base (code 93), and cranial vault (code 94). Levels 2 and 3 focus on further defining the fracture locations and for fracture morphology, achieving an almost individual mapping of the fracture pattern. This introductory article describes the rationale for the comprehensive AO CMF classification system, discusses the methodological framework, and provides insight into the experiences and interactions during the evaluation process within the core groups. The details of this system in terms of anatomy and levels are presented in a series of focused tutorials illustrated with case examples in this special issue of the Journal. PMID:25489387

  12. 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

  13. 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. PMID:23238939

  14. Oldest Known Pantherine Skull and Evolution of the Tiger

    PubMed Central

    Mazák, Ji H.; Christiansen, Per; Kitchener, Andrew C.

    2011-01-01

    The tiger is one of the most iconic extant animals, and its origin and evolution have been intensely debated. Fossils attributable to extant pantherine species-lineages are less than 2 MYA and the earliest tiger fossils are from the Calabrian, Lower Pleistocene. Molecular studies predict a much younger age for the divergence of modern tiger subspecies at <100 KYA, although their cranial morphology is readily distinguishable, indicating that early Pleistocene tigers would likely have differed markedly anatomically from extant tigers. Such inferences are hampered by the fact that well-known fossil tiger material is middle to late Pleistocene in age. Here we describe a new species of pantherine cat from Longdan, Gansu Province, China, Panthera zdanskyi sp. nov. With an estimated age of 2.55–2.16 MYA it represents the oldest complete skull of a pantherine cat hitherto found. Although smaller, it appears morphologically to be surprisingly similar to modern tigers considering its age. Morphological, morphometric, and cladistic analyses are congruent in confirming its very close affinity to the tiger, and it may be regarded as the most primitive species of the tiger lineage, demonstrating the first unequivocal presence of a modern pantherine species-lineage in the basal stage of the Pleistocene (Gelasian; traditionally considered to be Late Pliocene). This find supports a north-central Chinese origin of the tiger lineage, and demonstrates that various parts of the cranium, mandible, and dentition evolved at different rates. An increase in size and a reduction in the relative size of parts of the dentition appear to have been prominent features of tiger evolution, whereas the distinctive cranial morphology of modern tigers was established very early in their evolutionary history. The evolutionary trend of increasing size in the tiger lineage is likely coupled to the evolution of its primary prey species. PMID:22016768

  15. Breaking symmetry: the marine environment, prey size, and the evolution of asymmetry in cetacean skulls.

    PubMed

    MacLeod, C D; Reidenberg, J S; Weller, M; Santos, M B; Herman, J; Goold, J; Pierce, G J

    2007-06-01

    Skulls of odontocetes (toothed whales, including dolphins and porpoises) are typified by directional asymmetry, particularly in elements associated with the airway. Generally, it is assumed this asymmetry is related to biosonar production. However, skull asymmetry may actually be a by-product of selection pressure for an asymmetrically positioned larynx. The odontocete larynx traverses the pharynx and is held permanently in place by a ring of muscle. This allows prey swallowing while remaining underwater without risking water entering the lungs and causing injury or death. However, protrusion of the larynx through the pharynx causes a restriction around which prey must pass to reach the stomach. The larynx and associated hyoid apparatus has, therefore, been shifted to the left to provide a larger right piriform sinus (lateral pharyngeal food channel) for swallowing larger prey items. This asymmetry is reflected in the skull, particularly the dorsal openings of the nares. It is hypothesized that there is a relationship between prey size and skull asymmetry. This relationship was examined in 13 species of odontocete cetaceans from the northeast Atlantic, including four narrow-gaped genera (Mesoplodon, Ziphius, Hyperoodon, and Kogia) and eight wide-gaped genera (Phocoena, Delphinus, Stenella, Lagenorhynchus, Tursiops, Grampus, Globicephala, and Orcinus). Skulls were examined from 183 specimens to assess asymmetry of the anterior choanae. Stomach contents were examined from 294 specimens to assess prey size. Results show there is a significant positive relationship between maximum relative prey size consumed and average asymmetry relative to skull size in odontocete species (wide-gape species: R2 = 0.642, P = 0.006; narrow-gape species: R2 = 0.909, P = 0.031). This finding provides support for the hypothesis that the directional asymmetry found in odontocete skulls is related to an aquatic adaptation enabling swallowing large, whole prey while maintaining respiratory

  16. The relationship between skull morphology, masticatory muscle force and cranial skeletal deformation during biting.

    PubMed

    Toro-Ibacache, Viviana; Zapata Muñoz, Víctor; O'Higgins, Paul

    2016-01-01

    The human skull is gracile when compared to many Middle Pleistocene hominins. It has been argued that it is less able to generate and withstand high masticatory forces, and that the morphology of the lower portion of the modern human face correlates most strongly with dietary characteristics. This study uses geometric morphometrics and finite element analysis (FEA) to assess the relationship between skull morphology, muscle force and cranial deformations arising from biting, which is relevant in understanding how skull morphology relates to mastication. The three-dimensional skull anatomies of 20 individuals were reconstructed from medical computed tomograms. Maximal contractile muscle forces were estimated from muscular anatomical cross-sectional areas (CSAs). Fifty-nine landmarks were used to represent skull morphology. A partial least squares analysis was performed to assess the association between skull shape and muscle force, and FEA was used to compare the deformation (strains) generated during incisor and molar bites in two individuals representing extremes of morphological variation in the sample. The results showed that only the proportion of total muscle CSA accounted for by the temporalis appears associated with skull morphology, albeit weekly. However, individuals with a large temporalis tend to possess a relatively wider face, a narrower, more vertically oriented maxilla and a lower positioning of the coronoid process. The FEAs showed that, despite differences in morphology, biting results in similar modes of deformation for both crania, but with localised lower magnitudes of strains arising in the individual with the narrowest, most vertically oriented maxilla. Our results suggest that the morphology of the maxilla modulates the transmission of forces generated during mastication to the rest of the cranium by deforming less in individuals with the ability to generate proportionately larger temporalis muscle forces. PMID:25829126

  17. Comparison of conventional and skull base surgical approaches for the excision of trigeminal neurinomas.

    PubMed

    Taha, J M; Tew, J M; van Loveren, H R; Keller, J T; el-Kalliny, M

    1995-05-01

    Trigeminal neurinomas have traditionally been excised through conventional approaches. Because symptomatic tumor recurrence exceeds 50% after conventional procedures, the authors evaluated the use of skull base approaches to achieve complete resection and a lower rate of symptomatic recurrence. Comparisons of skull base with conventional approaches to trigeminal neurinomas have been limited to small series with short-term follow-up periods. The authors reviewed their experiences with conventional (frontotemporal transsylvian, subtemporal-intradural, subtemporal-transtentorial, and suboccipital) and skull base (frontotemporal extradural-intradural, frontoorbitozygomatic, subtemporal anterior petrosal, and presigmoid posterior petrosal) surgical approaches for the excision of trigeminal neurinomas. In this paper they report the results of 15 patients with trigeminal neurinoma who underwent 27 surgical procedures between 1980 and 1990. Seventeen of the procedures used conventional and 10 used skull base approaches. All patients had tumors arising from Meckel's cave and the porus trigeminus either initially or on recurrence. Tumors located in the cavernous sinus recurred most frequently (83%); other tumors that recurred frequently were those located in Meckel's cave and the porus trigeminus (67%), and the posterior fossa (17%). The tumor extended into the anterolateral wall of the cavernous sinus in 38% of patients with cavernous sinus involvement. Tumor exposure and ease of dissection were superior with skull base approaches. Residual or recurrent tumors were found in 65% of patients following conventional approaches compared with 10% of patients following skull base approaches. Using skull base approaches, the surgeon was more accurate (90%) in estimating tumor excision than when using conventional approaches (43%). Perioperative complications were similar with both. The authors discuss the indications, advantages, and limitations of each approach. Based on

  18. 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

  19. Bilaterally symmetric Fourier approximations of the skull outlines of temnospondyl amphibians and their bearing on shape comparison.

    PubMed

    Sengupta, Dhurjati P; Sengupta, Debapriya; Ghosh, Parthasarathi

    2005-06-01

    Present work illustrates a scheme of quantitative description of the shape of the skull outlines of temnospondyl amphibians using bilaterally symmetric closed Fourier curves. Some special points have been identified on the Fourier fits of the skull outlines, which are the local maxima, or minima of the distances from the centroid of the points at the skull outline. These points denotes break in curvature of the outline and their positions can be compared to differentiate the skull shapes. The ratios of arc-lengths of the posterior and lateral outline of 58 temnospondyl skulls have been plotted to generate a triaguarity series of the skulls. This series grades different families, some of their genera and species as well as some individuals according to their posterior and lateral skull length ratios. This model while comparing different taxa, takes into account the entire arc-length of the outline of the temnospondyl skulls, and does not depend on few geometric or biological points used by earlier workers for comparing skull shapes. PMID:16052076

  20. Robust fast automatic skull stripping of MRI-T2 data

    NASA Astrophysics Data System (ADS)

    Rajagopalan, Srinivasan; Karwoski, Ronald A.; Robb, Richard

    2005-04-01

    The efficacy of image processing and analysis on skull stripped MR images vis-a-vis the original images is well established. Additionally, compliance with the Health Insurance Portability and Accountability Act (HIPAA) requires neuroimage repositories to anonymise the images before sharing them. This makes the non-trivial skull stripping process all the more significant. While a number of optimal approaches exist to strip the skull from T1-weighted MR images to the best of our knowledge, there is no simple, robust, fast, parameter free and fully automatic technique to perform the same on T2-weighted images. This paper presents a strategy to fill this gap. It employs a fast parameterization of the T2 image intensity onto a standardized T1 intensity scale. The parametric "T1-like" image obtained via the transformation, which takes only a few seconds to compute, is subsequently processed by any of the many T1-based brain extraction techniques to derive the brain mask. Masking the original T2 image with this brain mask strips the skull. By standardizing the intensity of the parametric image, preset algorithm-specific parameters (if any) could be used across multiple datasets. The proposed scheme has been used in a number of phantom and clinical T2 brain datasets to successfully strip the skull.

  1. Perioperative management of complex skull base surgery: the anesthesiologist's point of view.

    PubMed

    Jellish, W Scott; Murdoch, John; Leonetti, John P

    2002-05-15

    The anesthetic management of complex skull base surgical procedures provides unique problems and concerns for the neuroanesthesiologist. Positioning to access the skull base could put the patient at risk for peripheral nerve injury and some of the positions may increase the risk for air emboli. In addition, tumor pathology and involvement with vital structures could increase the chances for substantive blood loss, destruction of associated nerves or vessels, and may require temporary occlusion of the carotid artery necessitating intraoperative neuroprotection. Neurophysiological monitors may also be used to safeguard nerve function and anesthetic techniques must be adjusted to accommodate their use. Finally, postoperative morbidity may be affected by surgical approach to the skull base and the anesthesiologist should be aware of which approach may produce a greater incidence of pain, nausea, and vomiting in the postoperative period. The authors discuss the anesthetic concerns and management for complex cranial base surgery. Different approaches will be discussed and comparisons of perioperative parameters between these approaches will be made with data provided by retrospective chart review of more than 600 skull base procedures performed at the authors' institution over the last 10 years. This information should help guide decision making concerning anesthetic management for these skull base procedures. PMID:16119903

  2. A skull-based multiple dipole phantom for EEG and MEG studies

    SciTech Connect

    Spencer, M.E.; Leahy, R.M.; Mosher, J.C.

    1996-07-01

    A versatile phantom for use in evaluating forward and inverse methods for MEG and EEG has been designed and is currently being constructed. The phantom consists of three major components: (i) a 32-element cur- rent dipole array, (ii) a PC-controlled dipole driver with 32 isolated channels allowing independent control of each dipole, (iii) spherical and human-skull mounts in which the dipole array is placed. Materials were selected throughout the phantom to produce minimal field distortions and artifacts to enable acquisition of high quality EEG and MEG data. The dipoles are made from a rigid narrow (0.84 mm) stainless steel coax cable. The dipole drivers can be configured as either current or voltage sources, are independently programmable and fully isolated, and are capable of producing arbitrary bipolar waveforms up to a 200 Hz bandwidth. The spherical mount is a single shell sphere filled with conductive gelatin. The human skull mount has three shells: ``brain`` (conducting gelatin), ``skull`` (the skull is impregnated with a low conductivity conducting gelatin), and ``scalp`` (a thin layer of rubber latex mixed with NaCl to achieve a conductivity matched to the brain). The conductivities will be adjusted to achieve approximately an 80:1:80 ratio. Data collected to date from the spherical phantom shows excellent agreement between measured surface potentials and that predicted from theory (27 of the 32 dipoles give better than 99.9% rms fit) and negligible leakage between dipoles. We are currently completing construction of the skull mount.

  3. Embryonic development of the skull of the Andean lizard Ptychoglossus bicolor (Squamata, Gymnophthalmidae)

    PubMed Central

    Hernández-Jaimes, Carlos; Jerez, Adriana; Ramírez-Pinilla, Martha Patricia

    2012-01-01

    The study of cranial design and development in Gymnophthalmidae is important to understand the ontogenetic processes behind the morphological diversity of the group and to examine the possible effects of microhabitat use and other ecological parameters, as well as phylogenetic constraints, on skull anatomy. Complete morphological descriptions of embryonic skull development within Gymnophthalmidae are non-existent. Likewise, very little is known about the complete chondrocranium of the family. Herein, the development of the skull of the semi-fossorial lizard Ptychoglossus bicolor is described along with an examination of the chondrocranium of other gymnophthalmid taxa and the teiid Cnemidophorus lemniscatus. Cranial chondrification begins with early condensations in the ethmoid, orbitotemporal and occipital regions of the chondrocranium as well as the viscerocranium. Ossification of the skull starts with elements of the dermatocranium (pterygoid, prefrontal, maxilla and jugal). The orbitosphenoid is the last chondral bone to appear. At birth, the skull is almost completely ossified and exhibits a large frontoparietal fontanelle. In general terms, the chondrocranium of the gymnophthalmids studied is characteristic of lacertiform terrestrial lizards, in spite of their life habits, and resembles the chondrocranium of C. lemniscatus in many aspects. However, the gymnophthalmids show great variation in the orbitosphenoid and a complex nasal capsule. The latter exhibits greater development of some nasal cartilages, which make it more complex than in C. lemniscatus. These characteristics might be related to microhabitat use and the well-developed olfactory and vomeronasal systems observed within this clade. PMID:22881276

  4. The "skin-skull-brain model": a new instrument for the study of gunshot effects.

    PubMed

    Thali, M J; Kneubuehl, B P; Zollinger, U; Dirnhofer, R

    2002-02-18

    In order to create and study wound morphology, a "skin-skull-brain model" had to be designed which would make the laboratory reproduction of a real ballistic injury possible. To simulate the human skin, an artificial skin (a silicon cap) is used. This silicon scalp contains synthetic fibers (artificial leather) to simulate the collagen and fat of the scalp. The artificial skull is a layered polyurethane sphere (19 cm o.d.; and 5, 6, or 7 mm thick) constructed in a specially designed form with a Tabula externa, Tabula interna, and a porous Diploe sandwiched in between. The periostium of the artificial skull is made of latex. This elastic latex layer prevents the bone fragments from scattering after the model has been struck by gunfire. The brain itself is simulated with ordnance gelatin, 10% at 4 degrees C, a material well known in wound ballistics. Gunshots were fired at a distance of 10 m from the model. During the evaluation of the "skin-skull-brain model", it was possible to show that injuries inflicted to this model are fully comparable to the morphology of equivalent real gunshot injuries. Using the "skin-skull-brain model" has some significant advantages: the model is inexpensive, easy to construct, instantly available for use, and eliminates ethics conflicts. The main advantage of such a model is, in comparison with biological substances, the high reproducibility of inflicted traumas. PMID:11909661

  5. [NiTi shape-memory alloy cramp used in repair of skull defect].

    PubMed

    Wang, Z; Zhou, S; Tian, F

    1998-11-01

    Fixation of silicon-polyester fiber network on skull defect was usually difficult to handle and the fixation was unstable. In order to solve these problems, NiTi shape-memory alloy cramp was adopted and 101 patients with skull defects were selected for this clinical trial. Among them, there were 79 males and 22 females, and the age ranged from 12-55 years old. The area of skull defect ranged from 3 cm x 4 cm to 10 cm x 16 cm. All of these patients received repairing of the skull defects by silicon-polyester fiber network which was fixed by NiTi memory alloy cramps. After operation, there was no complication. One hundred patients were followed up for 1-8 years, in which 97 cases returned to their normal work, and only 2 cases had a transient dysfunction of frontal muscle for 2 months. In addition, There were no loosening of the cramps, displacement of plastic network and malignant degeneration. The NiTi shape-memory alloy cramps had the following advantages: 1. Simple operative procedure; 2. Rigid fixation; 3. Mild postoperative tissue reaction; 4. Few postoperative complication; 5. Favorable effect of skull repair; 6. No interference with CT and MRI image; 7. No carcinogenicity. PMID:10437089

  6. The role of the zygomatic arch in the statics of the skull and its adaptive shape.

    PubMed

    Witzel, U; Preuschoft, H; Sick, H

    2004-01-01

    The zygomatic arch of mammals is usually considered a phylogenetic relic of the fenestrations of the skull roof which may be observed in morphological sequences of primitive vertebrate skulls. If this concept is correct, the element is comparable (though not homologous) to the jugal arches of diapsid reptiles. Two major questions then remain unanswered: why different elements are maintained in reptiles and mammals during evolution, and why the arches are maintained as relics of ancestral forms. It is tempting to respond to the latter question with a very simple answer, namely that the elements function in order to sustain mechanical stresses. In this paper, we raise the questions which quality of stresses occurs in a primate skull within the zygomatic arches and what relationship these stresses hold to the morphology of these bony elements. An answer has been sought by means of finite element stress analysis. We found that the zygomatic arch in primate skulls represents a structure which carries, under all biologically relevant conditions, either compressive or tensile stresses. In a very simple model of the human skull under bite forces, a strip of stresses occurs lateral to the orbits, which seems roughly comparable to the zygomatic arch. Once such a structure exists and is used as an insertion of adductor muscles, it will be exposed to bending stress in side view and in frontal view. Morphological details of the zygomatic arch (curvature, profile, suture) are well suited to sustain the evoked stresses by a minimum of material. PMID:15316151

  7. Morphological Variations in the Transverse Venous Sinus Anatomy of Dogs and its Relationship to Skull Landmarks.

    PubMed

    Carreira, L Miguel; Ferreira, A

    2016-08-01

    We characterized the anatomical morphology of the transverse venous sinus (TVS) of 69 canine adult cadavers belonging to three groups: brachycephalic (B), dolichocephalic (D) and mesaticephalic (M). In addition, we outlined its path over the skull using five classic human craniometric points (CPs): the asterion (ast), the bregma (b), the glabella (g), the stephanion (st) and the pterion (pt). The study aimed to establish anatomical differences in the TVS between groups and in the relationship between the TVS and skull. We found that TVS anatomy and its relationships to skull landmarks vary markedly between the groups, with similar anatomical arrangements in B and M. The TVS length can be ranked as M < B < D (with D being the biggest), whereas the width can be ranked as M < D < B (with B being the widest) with the right side being smaller than the left. In the B and M groups, the TVS assumes a craniocaudal trajectory that is closer to the lateral skull wall than in D, where the TVS presents a caudocranial direction. By documenting the morphological characteristics of the TVS, we can create a set of anatomical references allowing construction of a basic framework to greatly decrease the probability of TVS injury during neuronavigation procedures when supported by a good knowledge of the skull, brain anatomies and their relationships. PMID:26315333

  8. Esthetic Craniofacial Bony and Skull Base Reconstruction Using Flap Wrapping Technique.

    PubMed

    Yano, Tomoyuki; Suesada, Nobuko; Usami, Satoshi

    2016-07-01

    For a safe and esthetic skull base reconstruction combined with repair of craniofacial bone defects, the authors introduce the flap wrapping technique in this study. This technique consists of skull base reconstruction using the vastus lateralis muscle of an anterolateral thigh (ALT) free flap, and structural craniofacial bony reconstruction using an autologous calvarial bone graft. The key to this technique is that all of the grafted autologous bone is wrapped with the vascularized fascia of the ALT free flap to protect the grafted bone from infection and exposure. Two anterior skull base tumors combined with craniofacial bony defects were included in this study. The subjects were a man and a woman, aged 18 and 64. Both patients had preoperative proton beam therapy. First, the skull base defect was filled with vastus lateralis muscle, and then structural reconstruction was performed with an autologous bone graft and a fabricated inner layer of calvarial bone, and then the grafted bone was completely wrapped in the vascularized fascia of the ALT free flap. By applying this technique, there was no intracranial infection or grafted bone exposure in these 2 patients postoperatively, even though both patients had preoperative proton beam therapy. Additionally, the vascularized fascia wrapped bone graft could provide a natural contour and prevent collapse of the craniofacial region, and this gives patients a better facial appearance even though they have had skull base surgery. PMID:27300454

  9. Utility of postmortem imaging system for anatomical education in skull base surgery.

    PubMed

    Kodera, Toshiaki; Arishima, Hidetaka; Kitai, Ryuhei; Kikuta, Ken-ichiro; Iino, Satoshi; Noriki, Sakon; Naiki, Hironobu

    2015-01-01

    Although cadaver dissections are important for skull base surgeons to acquire anatomical knowledge and techniques, their opportunities are limited in Japan. The Autopsy Imaging Center of the University of Fukui Hospital has both a CT scanner and an MR unit solely for deceased patients. The authors applied the postmortem imaging to cadaver dissections and evaluated its usefulness in surgical education. Ten sides of five formalin-fixed cadaver heads were dissected by ten neurosurgeons. Five neurosurgeons were young, three were moderately experienced, and two were experts in skull base surgery. They performed orbitozygomatic, anterior transpetrosal, posterior transpetrosal, and transcondylar approaches. CT bone images were taken before and after dissections, and MR images were taken before dissection to merge with the CT bone images. The usefulness of the images for each neurosurgeon and for each skull base approach was evaluated. The postmortem imaging system was useful for all neurosurgeons, especially in anterior transpetrosal, posterior transpetrosal, and transcondylar approaches. They could find the insufficiency or excessiveness of their drilling of specific bony structures with the images. Even the experts in skull base surgery could identify regions in which they could add drilling safely to widen the surgical field more. The postmortem imaging system was useful for skull base cadaver dissections. This system is expected to be utilized for education and research on surgical anatomy. PMID:25240531

  10. Endonasal Skull Base Tumor Removal Using Concentric Tube Continuum Robots: A Phantom Study.

    PubMed

    Swaney, Philip J; Gilbert, Hunter B; Webster, Robert J; Russell, Paul T; Weaver, Kyle D

    2015-03-01

    Objectives The purpose of this study is to experimentally evaluate the use of concentric tube continuum robots in endonasal skull base tumor removal. This new type of surgical robot offers many advantages over existing straight and rigid surgical tools including added dexterity, the ability to scale movements, and the ability to rotate the end effector while leaving the robot fixed in space. In this study, a concentric tube continuum robot was used to remove simulated pituitary tumors from a skull phantom. Design The robot was teleoperated by experienced skull base surgeons to remove a phantom pituitary tumor within a skull. Percentage resection was measured by weight. Resection duration was timed. Setting Academic research laboratory. Main Outcome Measures Percentage removal of tumor material and procedure duration. Results Average removal percentage of 79.8 ± 5.9% and average time to complete procedure of 12.5 ± 4.1 minutes (n = 20). Conclusions The robotic system presented here for use in endonasal skull base surgery shows promise in improving the dexterity, tool motion, and end effector capabilities currently available with straight and rigid tools while remaining an effective tool for resecting the tumor. PMID:27054057

  11. Surgery of the ear and the lateral skull base: pitfalls and complications

    PubMed Central

    Schick, Bernhard; Dlugaiczyk, Julia

    2013-01-01

    Surgery of the ear and the lateral skull base is a fascinating, yet challenging field in otorhinolaryngology. A thorough knowledge of the associated complications and pitfalls is indispensable for the surgeon, not only to provide the best possible care to his patients, but also to further improve his surgical skills. Following a summary about general aspects in pre-, intra-and postoperative care of patients with disorders of the ear/lateral skull base, this article covers the most common pitfalls and complications in stapes surgery, cochlear implantation and surgery of vestibular schwannomas and jugulotympanal paragangliomas. Based on these exemplary procedures, basic “dos and don’ts” of skull base surgery are explained, which the reader can easily transfer to other disorders. Special emphasis is laid on functional aspects, such as hearing, balance and facial nerve function. Furthermore, the topics of infection, bleeding, skull base defects, quality of life and indication for revision surgery are discussed. An open communication about complications and pitfalls in ear/lateral skull base surgery among surgeons is a prerequisite for the further advancement of this fascinating field in ENT surgery. This article is meant to be a contribution to this process. PMID:24403973

  12. Are Diet Preferences Associated to Skulls Shape Diversification in Xenodontine Snakes?

    PubMed Central

    Klaczko, Julia; Sherratt, Emma; Setz, Eleonore Z. F.

    2016-01-01

    Snakes are a highly successful group of vertebrates, within great diversity in habitat, diet, and morphology. The unique adaptations for the snake skull for ingesting large prey in more primitive macrostomatan snakes have been well documented. However, subsequent diversification in snake cranial shape in relation to dietary specializations has rarely been studied (e.g. piscivory in natricine snakes). Here we examine a large clade of snakes with a broad spectrum of diet preferences to test if diet preferences are correlated to shape variation in snake skulls. Specifically, we studied the Xenodontinae snakes, a speciose clade of South American snakes, which show a broad range of diets including invertebrates, amphibians, snakes, lizards, and small mammals. We characterized the skull morphology of 19 species of xenodontine snakes using geometric morphometric techniques, and used phylogenetic comparative methods to test the association between diet and skull morphology. Using phylogenetic partial least squares analysis (PPLS) we show that skull morphology is highly associated with diet preferences in xenodontine snakes. PMID:26886549

  13. Ontogenetic allometry, heterochrony, and interspecific differences in the skull of African apes, using tridimensional Procrustes analysis.

    PubMed

    Berge, Christine; Penin, Xavier

    2004-06-01

    Ontogenetic studies of African ape skulls lead to an analysis of morphological differences in terms of allometry, heterochrony, and sexual dimorphism. The use of geometric morphometrics allows us 1) to define size and shape variations as independent factors (an essential but seldom respected condition for heterochrony), and 2) to calculate in percentage of shape changes and to graphically represent the parts of shape variation which are related to various biological phenomena: common allometry, intraspecific allometry, and allometric and nonallometric shape discrimination. Three tridimensional Procrustes analyses and the calculation of multivariate allometries, discriminant functions, and statistical tests are used to compare the skulls of 50 Pan troglodytes, and 50 Gorilla gorilla of different dental stages. The results both complement and modify classical results obtained from similar material but with different methods. Size and Scaling in Primate Morphology, New York: Plenum, p. 175-205). As previously described by Shea, the common growth allometric pattern is very important (64% of total shape variation). It corresponds to a larger increase of facial volume than of neurocranial volume, a more obliquely oriented foramen magnum, and a noticeable reshaping of the nuchal region (higher inion). However, the heterochronic interpretation based on common allometry is rather different from Shea. Gorillas differ from chimpanzees not only with a larger magnitude of allometric change (rate peramorphosis), as is classically said, but also grow more in size than in shape (size acceleration). In other words, for a similar stage of growth, gorillas have the size and shape corresponding to older chimpanzees, and for a similar shape, gorillas have a larger size than chimpanzees. In contrast, sexual dimorphism actually corresponds to allometric changes only, as classically demonstrated (time hypermorphosis). Sexual dimorphism is here significant in adult gorillas alone, and

  14. Negative pressure technology enhances bone regeneration in rabbit skull defects

    PubMed Central

    2013-01-01

    Background Bone is a slowly regenerating tissue influenced by various physiological processes, including proliferation, differentiation, and angiogenesis, under the control of growth factors. Shortening this healing time is an important and popular clinical research focus in orthopedics. Negative pressure can stimulate angiogenesis, improve blood circulation, promote granulation tissue growth and accelerate tissue wound healing. We sought to determine whether negative pressure could reduce bone healing time in a rabbit cranial defect model. Methods Four symmetrical holes (diameter, 3.5 mm) were drilled into the skulls of 42 New Zealand white rabbits, with two holes in each parietal bone. For each rabbit, the two sides were then randomly assigned into experimental and control groups. Using negative pressure suction tubes, experimental holes were treated with −50 kPa for 15 minutes, four times per day, whereas the control holes remained untreated. After 4 weeks, the negative pressure suction tubes were removed. At 2, 4, 6 and 8 weeks, three-dimensional (3D) reconstruction computed tomography (CT), X-ray radiopacity, and two-photon absorptiometry were used to evaluate new bone formation. Histological changes were determined by hematoxylin and eosin (H.E) staining. At weekly intervals until 6 weeks, the mRNA expression levels of vascular endothelial growth factor (VEGF) and bone morphogenetic protein (BMP)-2 were evaluated by RT-PCR. A paired student’s t-test was employed to compare X-ray radiopacity and bone density measurements between the experimental and control groups. Results 3D-reconstruction CT showed that new bone regeneration in the experimental group was greater than that in the control group at 4 and 6 weeks. At these time points, the experimental group presented with higher X-ray radiopacity and increased bone density (P < 0.05) as compared with the control group. Cartilage islands and new bone were observed by H.E staining at 2

  15. 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

  16. Bone fracture repair - slideshow

    MedlinePlus

    ... page: //medlineplus.gov/ency/presentations/100077.htm Bone fracture repair - series To use the sharing features on ... to slide 4 out of 4 Indications Overview Fractures of the bones are classified in a number ...

  17. Forearm Fractures in Children

    MedlinePlus

    .org Forearm Fractures in Children The forearm is the part of the arm between the wrist and the elbow. It is ... two bones: the radius and the ulna. Forearm fractures are common in childhood, accounting for more than ...

  18. Nasal fracture - aftercare

    MedlinePlus

    ... page: //medlineplus.gov/ency/patientinstructions/000554.htm Nasal fracture - aftercare To use the sharing features on this ... that gives your nose its shape. A nasal fracture occurs when the bony part of your nose ...

  19. 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 ...

  20. Hip fracture surgery

    MedlinePlus

    ... neck fracture repair; Trochanteric fracture repair; Hip pinning surgery; Osteoarthritis-hip ... You may receive general anesthesia before this surgery. This means ... spinal anesthesia. With this kind of anesthesia, medicine is ...

  1. Nanofibrous Synthetic Dural Patch for Skull Base Defects: Preliminary Experience for Reconstruction after Extended Endonasal Approaches

    PubMed Central

    Zenga, Francesco; Tardivo, Valentina; Pacca, Paolo; Garzaro, Massimiliano; Garbossa, Diego; Ducati, Alessandro

    2016-01-01

    Setting One of the consequences of the widespread use of endoscopic endonasal approaches (EEA) to skull base pathologies is the management of complex skull base defects. Nowadays, the gold standard is a multilayer closure that reproduces the physiological tissue barriers. Several techniques have been described in the literature; however, skull base reconstruction after EEA still represents a matter of debate, especially after extended EEA. A watertight closure is paramount to prevent cerebrospinal fluid leak and meningitis. Design Regarding this issue, we present our experience with a new synthetic dural patch, ReDura (Medprin Biotech, La Mirada, California, United States), as a subdural inlay in three patients who underwent endoscopic endonasal removal of sellar and suprasellar lesions. Conclusions ReDura patch showed the same versatility of autologous iliotibial tract. A dural patch that easily adapts to all defects, revealed to be a useful tool for performing watertight closure, possibly in a short operative time, after endoscopic approaches. PMID:26937335

  2. The Pursuit of a Cholesteatoma by Harvey Cushing: Staged Approach to a Complex Skull Base Tumor

    PubMed Central

    Malekpour, Mahdi; Cohen-Gadol, Aaron A.

    2014-01-01

    Objective The evolution of neurosurgical techniques during Harvey Cushing's practice was immense. The authors illustrate this evolution using archived historical records from Harvey Cushing. Setting Historical patient records retained by the Cushing Center at Yale University Department of Neurosurgery. Design The authors present the case of one of Cushing's patients with a cholesteatoma. Results Cushing's surgical treatment of a cholesteatoma extending into the skull base is an example of his meticulous documentation and accelerated surgical techniques. Conclusions This case demonstrates how neurosurgical techniques advanced in the management of complex skull base tumors via a staged approach through the middle and posterior fossae at a time long before the development of modern skull base surgery. PMID:25276599

  3. Intraoperative Neurophysiological Monitoring for Endoscopic Endonasal Approaches to the Skull Base: A Technical Guide.

    PubMed

    Singh, Harminder; Vogel, Richard W; Lober, Robert M; Doan, Adam T; Matsumoto, Craig I; Kenning, Tyler J; Evans, James J

    2016-01-01

    Intraoperative neurophysiological monitoring during endoscopic, endonasal approaches to the skull base is both feasible and safe. Numerous reports have recently emerged from the literature evaluating the efficacy of different neuromonitoring tests during endonasal procedures, making them relatively well-studied. The authors report on a comprehensive, multimodality approach to monitoring the functional integrity of at risk nervous system structures, including the cerebral cortex, brainstem, cranial nerves, corticospinal tract, corticobulbar tract, and the thalamocortical somatosensory system during endonasal surgery of the skull base. The modalities employed include electroencephalography, somatosensory evoked potentials, free-running and electrically triggered electromyography, transcranial electric motor evoked potentials, and auditory evoked potentials. Methodological considerations as well as benefits and limitations are discussed. The authors argue that, while individual modalities have their limitations, multimodality neuromonitoring provides a real-time, comprehensive assessment of nervous system function and allows for safer, more aggressive management of skull base tumors via the endonasal route. PMID:27293965

  4. Cranial sutures work collectively to distribute strain throughout the reptile skull.

    PubMed

    Curtis, Neil; Jones, M E H; Evans, S E; O'Higgins, P; Fagan, M J

    2013-09-01

    The skull is composed of many bones that come together at sutures. These sutures are important sites of growth, and as growth ceases some become fused while others remain patent. Their mechanical behaviour and how they interact with changing form and loadings to ensure balanced craniofacial development is still poorly understood. Early suture fusion often leads to disfiguring syndromes, thus is it imperative that we understand the function of sutures more clearly. By applying advanced engineering modelling techniques, we reveal for the first time that patent sutures generate a more widely distributed, high level of strain throughout the reptile skull. Without patent sutures, large regions of the skull are only subjected to infrequent low-level strains that could weaken the bone and result in abnormal development. Sutures are therefore not only sites of bone growth, but could also be essential for the modulation of strains necessary for normal growth and development in reptiles. PMID:23804444

  5. Giant primary ossified cavernous hemangioma of the skull in an adult: A rare calvarial tumor

    PubMed Central

    Tyagi, Devendra K; Balasubramaniam, Srikant; Sawant, Hemant V

    2011-01-01

    Primary intraosseous cavernous hemangiomas (PICHs) of the cranium are rare benign vascular tumors that account for about 0.2 % of all bone tumors and 10 % of benign skull tumors. They generally present as osteolytic lesions with honeycomb pattern of calcification. Completely ossified cavernous hemangioma of the calvarium in an adult has not been reported previously. A 28-year-old female presented to us with a large right parietal skull mass that had been present since the last 15 years. Total resection of the lesion was performed. Pathological examination was suggestive of cavernous hemangioma of the skull bone. Cavernous hemangioma should be considered as one of the differential diagnosis in any case of bony swelling of the calvarium so that adequate preoperative planning can be made to minimize blood loss and subsequent morbidity. PMID:21897684

  6. An exceptional fossil skull from South America and the origins of the archosauriform radiation.

    PubMed

    Pinheiro, Felipe L; França, Marco A G; Lacerda, Marcel B; Butler, Richard J; Schultz, Cesar L

    2016-01-01

    Birds, dinosaurs, crocodilians, pterosaurs and their close relatives form the highly diverse clade Archosauriformes. Archosauriforms have a deep evolutionary history, originating in the late Permian, prior to the end-Permian mass extinction, and radiating in the Triassic to dominate Mesozoic ecosystems. However, the origins of this clade and its extraordinarily successful body plan remain obscure. Here, we describe an exceptionally preserved fossil skull from the Lower Triassic of Brazil, representing a new species, Teyujagua paradoxa, transitional in morphology between archosauriforms and more primitive reptiles. This skull reveals for the first time the mosaic assembly of key features of the archosauriform skull, including the antorbital and mandibular fenestrae, serrated teeth, and closed lower temporal bar. Phylogenetic analysis recovers Teyujagua as the sister taxon to Archosauriformes, and is congruent with a two-phase model of early archosauriform evolution, in response to two mass extinctions occurring at the end of the Guadalupian and the Permian. PMID:26965521

  7. An exceptional fossil skull from South America and the origins of the archosauriform radiation

    PubMed Central

    Pinheiro, Felipe L.; França, Marco A. G.; Lacerda, Marcel B.; Butler, Richard J.; Schultz, Cesar L.

    2016-01-01

    Birds, dinosaurs, crocodilians, pterosaurs and their close relatives form the highly diverse clade Archosauriformes. Archosauriforms have a deep evolutionary history, originating in the late Permian, prior to the end-Permian mass extinction, and radiating in the Triassic to dominate Mesozoic ecosystems. However, the origins of this clade and its extraordinarily successful body plan remain obscure. Here, we describe an exceptionally preserved fossil skull from the Lower Triassic of Brazil, representing a new species, Teyujagua paradoxa, transitional in morphology between archosauriforms and more primitive reptiles. This skull reveals for the first time the mosaic assembly of key features of the archosauriform skull, including the antorbital and mandibular fenestrae, serrated teeth, and closed lower temporal bar. Phylogenetic analysis recovers Teyujagua as the sister taxon to Archosauriformes, and is congruent with a two-phase model of early archosauriform evolution, in response to two mass extinctions occurring at the end of the Guadalupian and the Permian. PMID:26965521

  8. Mammalian skull heterochrony reveals modular evolution and a link between cranial development and brain size

    PubMed Central

    Koyabu, Daisuke; Werneburg, Ingmar; Morimoto, Naoki; Zollikofer, Christoph P. E.; Forasiepi, Analia M.; Endo, Hideki; Kimura, Junpei; Ohdachi, Satoshi D.; Truong Son, Nguyen; Sánchez-Villagra, Marcelo R.

    2014-01-01

    The multiple skeletal components of the skull originate asynchronously and their developmental schedule varies across amniotes. Here we present the embryonic ossification sequence of 134 species, covering all major groups of mammals and their close relatives. This comprehensive data set allows reconstruction of the heterochronic and modular evolution of the skull and the condition of the last common ancestor of mammals. We show that the mode of ossification (dermal or endochondral) unites bones into integrated evolutionary modules of heterochronic changes and imposes evolutionary constraints on cranial heterochrony. However, some skull-roof bones, such as the supraoccipital, exhibit evolutionary degrees of freedom in these constraints. Ossification timing of the neurocranium was considerably accelerated during the origin of mammals. Furthermore, association between developmental timing of the supraoccipital and brain size was identified among amniotes. We argue that cranial heterochrony in mammals has occurred in concert with encephalization but within a conserved modular organization. PMID:24704703

  9. An Account of the Inaugural Tessier Skull Exhibition at the University of Paris Descartes.

    PubMed

    Dusseldorp, Joseph Richard; Firmin, Françoise

    2015-10-01

    Paul Tessier is widely regarded as the father of modern craniofacial surgery. Upon his passing in 2008, his private collection of human skulls was purchased by the French Association of Facial Surgeons to ensure the collection would remain in France. The first public exhibition of the skulls was held in the medical museum of the University of Paris Descartes in April 2014. From this collection of skulls and the imagination of Tessier an entirely new specialty was created. Modern craniofacial surgery, now is an integral part of any pediatric plastic surgery department. Cranial and facial osteotomies have also become commonplace in both traumatic and aesthetic surgery. The goals for craniofacial deformity are now a return to completely normal appearance and function, as Tessier always believed they should be. PMID:26468782

  10. Methods on Skull Stripping of MRI Head Scan Images-a Review.

    PubMed

    Kalavathi, P; Prasath, V B Surya

    2016-06-01

    The high resolution magnetic resonance (MR) brain images contain some non-brain tissues such as skin, fat, muscle, neck, and eye balls compared to the functional images namely positron emission tomography (PET), single photon emission computed tomography (SPECT), and functional magnetic resonance imaging (fMRI) which usually contain relatively less non-brain tissues. The presence of these non-brain tissues is considered as a major obstacle for automatic brain image segmentation and analysis techniques. Therefore, quantitative morphometric studies of MR brain images often require a preliminary processing to isolate the brain from extra-cranial or non-brain tissues, commonly referred to as skull stripping. This paper describes the available methods on skull stripping and an exploratory review of recent literature on the existing skull stripping methods. PMID:26628083

  11. Intraoperative Neurophysiological Monitoring for Endoscopic Endonasal Approaches to the Skull Base: A Technical Guide

    PubMed Central

    Lober, Robert M.; Doan, Adam T.; Matsumoto, Craig I.; Kenning, Tyler J.; Evans, James J.

    2016-01-01

    Intraoperative neurophysiological monitoring during endoscopic, endonasal approaches to the skull base is both feasible and safe. Numerous reports have recently emerged from the literature evaluating the efficacy of different neuromonitoring tests during endonasal procedures, making them relatively well-studied. The authors report on a comprehensive, multimodality approach to monitoring the functional integrity of at risk nervous system structures, including the cerebral cortex, brainstem, cranial nerves, corticospinal tract, corticobulbar tract, and the thalamocortical somatosensory system during endonasal surgery of the skull base. The modalities employed include electroencephalography, somatosensory evoked potentials, free-running and electrically triggered electromyography, transcranial electric motor evoked potentials, and auditory evoked potentials. Methodological considerations as well as benefits and limitations are discussed. The authors argue that, while individual modalities have their limitations, multimodality neuromonitoring provides a real-time, comprehensive assessment of nervous system function and allows for safer, more aggressive management of skull base tumors via the endonasal route. PMID:27293965

  12. Functional Imaging of Human Vestibular Cortex Activity Elicited by Skull Tap and Auditory Tone Burst

    NASA Technical Reports Server (NTRS)

    Noohi, F.; Kinnaird, C.; Wood, S.; Bloomberg, J.; Mulavara, A.; Seidler, R.

    2016-01-01

    The current study characterizes 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 either the vestibulo-spinal reflex (saccular-mediated colic Vestibular Evoked Myogenic Potentials (cVEMP)), or the ocular muscle response (utricle-mediated ocular VEMP (oVEMP)). Some researchers have reported that air-conducted skull tap elicits both saccular and utricle-mediated VEMPs, while being faster and less irritating for the subjects. 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 otolith-specific deficits, including gait and balance problems that astronauts experience upon returning to earth. Previous imaging studies have documented activity in the anterior and posterior insula, superior temporal gyrus, inferior parietal lobule, inferior frontal gyrus, and the anterior cingulate cortex in response to different modes of vestibular stimulation. Here we hypothesized that skull taps elicit similar patterns of cortical activity as the auditory tone bursts, and previous vestibular imaging studies. Subjects wore bilateral MR compatible skull tappers and headphones inside the 3T GE scanner, while lying in the supine position, with eyes closed. Subjects received both forms of the stimulation in a counterbalanced fashion. Pneumatically powered skull tappers were placed bilaterally on the cheekbones. The vibration of the cheekbone was transmitted to the vestibular system, resulting in the vestibular cortical response. Auditory tone bursts were also delivered for comparison. To validate our stimulation method, we measured the ocular VEMP outside of the scanner. This measurement showed that both skull tap and auditory

  13. Effects of spatial variation of skull and cerebrospinal fluid layers on optical mapping of brain activities

    NASA Astrophysics Data System (ADS)

    Wang, Shuping; Shibahara, Nanae; Kuramashi, Daishi; Okawa, Shinpei; Kakuta, Naoto; Okada, Eiji; Maki, Atsushi; Yamada, Yukio

    2010-07-01

    In order to investigate the effects of anatomical variation in human heads on the optical mapping of brain activity, we perform simulations of optical mapping by solving the photon diffusion equation for layered-models simulating human heads using the finite element method (FEM). Particularly, the effects of the spatial variations in the thicknesses of the skull and cerebrospinal fluid (CSF) layers on mapping images are investigated. Mapping images of single active regions in the gray matter layer are affected by the spatial variations in the skull and CSF layer thicknesses, although the effects are smaller than those of the positions of the active region relative to the data points. The increase in the skull thickness decreases the sensitivity of the images to active regions, while the increase in the CSF layer thickness increases the sensitivity in general. The images of multiple active regions are also influenced by their positions relative to the data points and by their depths from the skin surface.

  14. Skull removal in MR images using a modified artificial bee colony optimization algorithm.

    PubMed

    Taherdangkoo, Mohammad

    2014-01-01

    Removal of the skull from brain Magnetic Resonance (MR) images is an important preprocessing step required for other image analysis techniques such as brain tissue segmentation. In this paper, we propose a new algorithm based on the Artificial Bee Colony (ABC) optimization algorithm to remove the skull region from brain MR images. We modify the ABC algorithm using a different strategy for initializing the coordinates of scout bees and their direction of search. Moreover, we impose an additional constraint to the ABC algorithm to avoid the creation of discontinuous regions. We found that our algorithm successfully removed all bony skull from a sample of de-identified MR brain images acquired from different model scanners. The obtained results of the proposed algorithm compared with those of previously introduced well known optimization algorithms such as Particle Swarm Optimization (PSO) and Ant Colony Optimization (ACO) demonstrate the superior results and computational performance of our algorithm, suggesting its potential for clinical applications. PMID:25059256

  15. A new head phantom with realistic shape and spatially varying skull resistivity distribution.

    PubMed

    Li, Jian-Bo; Tang, Chi; Dai, Meng; Liu, Geng; Shi, Xue-Tao; Yang, Bin; Xu, Can-Hua; Fu, Feng; You, Fu-Sheng; Tang, Meng-Xing; Dong, Xiu-Zhen

    2014-02-01

    Brain electrical impedance tomography (EIT) is an emerging method for monitoring brain injuries. To effectively evaluate brain EIT systems and reconstruction algorithms, we have developed a novel head phantom that features realistic anatomy and spatially varying skull resistivity. The head phantom was created with three layers, representing scalp, skull, and brain tissues. The fabrication process entailed 3-D printing of the anatomical geometry for mold creation followed by casting to ensure high geometrical precision and accuracy of the resistivity distribution. We evaluated the accuracy and stability of the phantom. Results showed that the head phantom achieved high geometric accuracy, accurate skull resistivity values, and good stability over time and in the frequency domain. Experimental impedance reconstructions performed using the head phantom and computer simulations were found to be consistent for the same perturbation object. In conclusion, this new phantom could provide a more accurate test platform for brain EIT research. PMID:24196845

  16. Cranial sutures work collectively to distribute strain throughout the reptile skull

    PubMed Central

    Curtis, Neil; Jones, M. E. H.; Evans, S. E.; O'Higgins, P.; Fagan, M. J.

    2013-01-01

    The skull is composed of many bones that come together at sutures. These sutures are important sites of growth, and as growth ceases some become fused while others remain patent. Their mechanical behaviour and how they interact with changing form and loadings to ensure balanced craniofacial development is still poorly understood. Early suture fusion often leads to disfiguring syndromes, thus is it imperative that we understand the function of sutures more clearly. By applying advanced engineering modelling techniques, we reveal for the first time that patent sutures generate a more widely distributed, high level of strain throughout the reptile skull. Without patent sutures, large regions of the skull are only subjected to infrequent low-level strains that could weaken the bone and result in abnormal development. Sutures are therefore not only sites of bone growth, but could also be essential for the modulation of strains necessary for normal growth and development in reptiles. PMID:23804444

  17. Pediatric Open Fractures.

    PubMed

    Trionfo, Arianna; Cavanaugh, Priscilla K; Herman, Martin J

    2016-07-01

    Open fractures in children are rare and are typically associated with better prognoses compared with their adult equivalents. Regardless, open fractures pose a challenge because of the risk of healing complications and infection, leading to significant morbidity even in the pediatric population. Therefore, the management of pediatric open fractures requires special consideration. This article comprehensively reviews the initial evaluation, classification, treatment, outcomes, and controversies of open fractures in children. PMID:27241379

  18. The Role of Skull Modeling in EEG Source Imaging for Patients with Refractory Temporal Lobe Epilepsy.

    PubMed

    Montes-Restrepo, Victoria; Carrette, Evelien; Strobbe, Gregor; Gadeyne, Stefanie; Vandenberghe, Stefaan; Boon, Paul; Vonck, Kristl; Mierlo, Pieter van

    2016-07-01

    We investigated the influence of different skull modeling approaches on EEG source imaging (ESI), using data of six patients with refractory temporal lobe epilepsy who later underwent successful epilepsy surgery. Four realistic head models with different skull compartments, based on finite difference methods, were constructed for each patient: (i) Three models had skulls with compact and spongy bone compartments as well as air-filled cavities, segmented from either computed tomography (CT), magnetic resonance imaging (MRI) or a CT-template and (ii) one model included a MRI-based skull with a single compact bone compartment. In all patients we performed ESI of single and averaged spikes marked in the clinical 27-channel EEG by the epileptologist. To analyze at which time point the dipole estimations were closer to the resected zone, ESI was performed at two time instants: the half-rising phase and peak of the spike. The estimated sources for each model were validated against the resected area, as indicated by the postoperative MRI. Our results showed that single spike analysis was highly influenced by the signal-to-noise ratio (SNR), yielding estimations with smaller distances to the resected volume at the peak of the spike. Although averaging reduced the SNR effects, it did not always result in dipole estimations lying closer to the resection. The proposed skull modeling approaches did not lead to significant differences in the localization of the irritative zone from clinical EEG data with low spatial sampling density. Furthermore, we showed that a simple skull model (MRI-based) resulted in similar accuracy in dipole estimation compared to more complex head models (based on CT- or CT-template). Therefore, all the considered head models can be used in the presurgical evaluation of patients with temporal lobe epilepsy to localize the irritative zone from low-density clinical EEG recordings. PMID:26936594

  19. A Morphologic and Morphometric Study of Foramen Vesalius in Dry Adult Human Skulls of Gujarat Region

    PubMed Central

    Singh, Praveen R.; Rajguru, Jaba

    2015-01-01

    Introduction: The foramen Vesalius is located within bony plate between the foramen ovale and the foramen rotundum in the floor of middle cranial fossa. This foramen allows passage of emissary veins which communicate cavernous sinus and pterygoid plexus of veins. AIM: To study the morphological and morphometric variations of foramen Vesalius in dry adult human skulls. Materials and Methods: One hundred and fifty dry adult human skulls were studied for variations in size, shape, presence/absence and any duplication/multiplication of the foramen Vesalius. After collecting data, appropriate statistical analysis was done. Results: The mean maximum dimension of foramen Vesalius was 0.98±0.67 mm on right side and 1.12±0.73 mm on left side. Foramen Vesalius was present in 90 (60%) skulls out of 150 observed. The incidence was 41(27.33%) on right side and 49 (32.67%) on left side. Foramen Vesalius was present unilaterally in 32 (35.56%) and bilaterally in 29 (32.23%) out of 90 skulls. Duplication of this foramen was observed in two skulls (one right side and one on left side). Foramen Vesalius was round in 72%, oval in 24% and irregular in 4% of total foramina present. Conclusion: Foramen Vesalius was present in 60% of total skulls studied. The foramen showed variations in incidence and shapes, while there was no statistically significant difference in the maximum dimension between foramen Vesalius on right and left side. There could be some developmental reasons to explain these variations. The findings of this study could be important to anatomists and also equally essential for clinicians who approach middle cranial cavity for various procedures. PMID:25859437

  20. Fractured tooth (image)

    MedlinePlus

    A tooth can be chipped or fractured during an accident or a bad fall. A tooth that is chipped or not badly fractured can usually be handled on a nonemergency basis. A tooth that is badly fractured may have exposed nerve ...

  1. 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

  2. Helmet therapy in infants with positional skull deformation: randomised controlled trial

    PubMed Central

    van Vlimmeren, Leo A; Groothuis-Oudshoorn, Catharina G M; Van der Ploeg, Catharina P B; IJzerman, Maarten J; Boere-Boonekamp, Magda M

    2014-01-01

    Objective To determine the effectiveness of helmet therapy for positional skull deformation compared with the natural course of the condition in infants aged 5-6 months. Design Pragmatic, single blinded, randomised controlled trial (HEADS, HElmet therapy Assessment in Deformed Skulls) nested in a prospective cohort study. Setting 29 paediatric physiotherapy practices; helmet therapy was administered at four specialised centres. Participants 84 infants aged 5 to 6 months with moderate to severe skull deformation, who were born after 36 weeks of gestation and had no muscular torticollis, craniosynostosis, or dysmorphic features. Participants were randomly assigned to helmet therapy (n=42) or to natural course of the condition (n=42) according to a randomisation plan with blocks of eight. Interventions Six months of helmet therapy compared with the natural course of skull deformation. In both trial arms parents were asked to avoid any (additional) treatment for the skull deformation. Main outcome measures The primary outcome was change in skull shape from baseline to 24 months of age assessed using plagiocephalometry (anthropometric measurement instrument). Change scores for plagiocephaly (oblique diameter difference index) and brachycephaly (cranioproportional index) were each included in an analysis of covariance, using baseline values as the covariate. Secondary outcomes were ear deviation, facial asymmetry, occipital lift, and motor development in the infant, quality of life (infant and parent measures), and parental satisfaction and anxiety. Baseline measurements were performed in infants aged between 5 and 6 months, with follow-up measurements at 8, 12, and 24 months. Primary outcome assessment at 24 months was blinded. Results The change score for both plagiocephaly and brachycephaly was equal between the helmet therapy and natural course groups, with a mean difference of −0.2 (95% confidence interval −1.6 to 1.2, P=0.80) and 0.2 (−1.7 to 2.2, P=0

  3. Atypical post-adenoidectomy Grisel's syndrome in Crouzon child with kyphotic skull base.

    PubMed

    Kourelis, Konstantinos; Haronis, Vasileios; Konandreas, Ioannis; Kontrafouri, Athina; Asimakopoulos, Athanasios

    2015-10-01

    Crouzon syndrome is characterized by abnormal craniofacial growth due to craniosynostosis. Skull base may also be involved in the pattern of malformations. Grisel's syndrome, an inflammation-mediated atlanto-axial instability occurs rarely in children after adenoidectomy. We report a 9-year-old female Crouzon patient, without vertebral anomalies, who developed severe torticollis few days after adenoid curettage. A deformity of the skull base alone might have induced an irregular arrangement of the craniocervical junction elements, thus increasing the susceptibility to cervical spine complications. PMID:25805067

  4. Skull Base Aneurysmal Bone Cyst Presented with Foramen Jugular Syndrome and Multi-Osseous Involvement

    PubMed Central

    Aghaghazvini, Leila; Sedighi, Nahid; Karami, Parisa; Yeganeh, Omid

    2012-01-01

    Aneurysmal bone cyst (ABC) is an expansile bone lesion that usually involves the long bones. Skull base involvement is rare. Hereby, we describe a 17-year-old man with hoarseness, facial asymmetry, left sided sensorineural hearing loss and left jugular foramen syndrome. CT scan and MRI showed a skull base mass that was confirmed as ABC in histopathology. The case was unusual and interesting due to the clinical presentation of jugular foramen syndrome and radiological findings such as severe enhancement and multiosseous involvement. PMID:23329983

  5. Modification of oxygen content in LiF crystals grown by skull method

    NASA Astrophysics Data System (ADS)

    Taranyuk, V.; Gektin, A.; Shiran, N.; Shlyakhturov, V.; Gridin, S.; Boiaryntseva, I.; Sofronov, D.

    2013-10-01

    The work is devoted to the controlled crystal growth procedure providing of optimal doping of dielectric halide materials (LiF crystals in particular). Two series of LiF crystals were studied. One series is represented by ultra- and nominal pure crystals, as well as crystals doped with polyvalent oxides (Nb2O5, WO3 and TiO2), which were grown by classical Kyropoulos method in vacuum, second series involves crystals grown using the skull method. It is shown that the skull technique is a quite efficient method of variously doped LiF crystal growth as compare with the classic Kyropoulos method.

  6. Transzygomatic Approach to Skull Base: History, Evolution, and Possibility of a Simple Modification.

    PubMed

    Badwal, Jaspreet Singh

    2016-05-01

    The surgical approaches to anterior, middle, and lateral skull base have evolved drastically, transcending from an era of oblivion to well-defined and systematically executed, state-of-the-art, refined surgery. The transzygomatic approach, which was developed to access the nasopharynx, has been applied to versatile locations of skull base pathology, with continuous evolution and modification of the osteotomies and skin flaps involved. A simple modification is proposed which could help reach a compromise between the wide exposure provided by the hemicoronal incision and the minimally invasive preauricular approach. PMID:27054426

  7. Resolution of “salt and pepper” appearance of the skull with vitamin D therapy

    PubMed Central

    Kaur, Gursimran; Singh, Parminder; Mittal, Naveen; Singla, Mani Kant

    2013-01-01

    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. PMID:24251156

  8. Late Pleistocene human skull from Hofmeyr, South Africa, and modern human origins.

    PubMed

    Grine, F E; Bailey, R M; Harvati, K; Nathan, R P; Morris, A G; Henderson, G M; Ribot, I; Pike, A W G

    2007-01-12

    The lack of Late Pleistocene human fossils from sub-Saharan Africa has limited paleontological testing of competing models of recent human evolution. We have dated a skull from Hofmeyr, South Africa, to 36.2 +/- 3.3 thousand years ago through a combination of optically stimulated luminescence and uranium-series dating methods. The skull is morphologically modern overall but displays some archaic features. Its strongest morphometric affinities are with Upper Paleolithic (UP) Eurasians rather than recent, geographically proximate people. The Hofmeyr cranium is consistent with the hypothesis that UP Eurasians descended from a population that emigrated from sub-Saharan Africa in the Late Pleistocene. PMID:17218524

  9. Reconstruction of posterior neck and skull with vertical trapezius musculocutaneous flap

    SciTech Connect

    Mathes, S.J.; Stevenson, T.R.

    1988-10-01

    The vertical trapezius musculocutaneous flap has been successfully utilized for reconstruction in 13 patients with complex posterior skull and neck defects. This flap based on its vascular pedicle, the descending branch of the transverse cervical artery, provides well-vascularized tissue for coverage of defects related to chronic osteomyelitis, tumor extirpation, osteoradionecrosis, and dehisced cervical laminectomy wounds. Emphasis on flap design, including the location of the skin island, allows adequate wound coverage, direct donor site closure, and muscle function preservation. With its large size and wide arc of rotation, the vertical trapezius musculocutaneous flap provides reliable coverage for posterior trunk, cervical, and skull defects.

  10. Confocal reflectance and two-photon microscopy studies of a songbird skull for preparation of transcranial imaging

    NASA Astrophysics Data System (ADS)

    Abi-Haidar, Darine; Oliver, Thomas

    2009-05-01

    We present experiments and analyses of confocal reflectance and two-photon microscopy studies of zebra finch skull samples. The thin and hollow structure of these birds' skulls is quite translucent, which can allow in vivo transcranial two-photon imaging for brain activation monitoring. However, the skull structure is also quite complex, with high refractive index changes on a macroscopic scale. These studies aim at exploring the geometrical and scattering properties of these skull samples with the use of several confocal microscopy contrasts. Moreover, the study of the axial reflectance exponential decay is used to estimate the scattering coefficients of the bone. Finally, two-photon imaging experiments of a fluorescent object located beneath the skull are carried out. It reveals that two-photon fluorescence can be collected through the skull with a strong signal. It also reveals that the spatial resolution loss is quite high and cannot be fully explained by the bulk scattering properties of the bone, but also by the presence of the high refractive index inhomogeneity of this pneumatic skull structure. Even if the optical properties of the skull are different during in vivo experiments, these preliminary studies are aimed at preparing and optimizing transcranial brain activation monitoring experiments on songbirds.

  11. A Three-Dimensional Finite-Element Model of a Human Dry Skull for Bone-Conduction Hearing

    PubMed Central

    2014-01-01

    A three-dimensional finite-element (FE) model of a human dry skull was devised for simulation of human bone-conduction (BC) hearing. Although a dry skull is a simplification of the real complex human skull, such model is valuable for understanding basic BC hearing processes. For validation of the model, the mechanical point impedance of the skull as well as the acceleration of the ipsilateral and contralateral cochlear bone was computed and compared to experimental results. Simulation results showed reasonable consistency between the mechanical point impedance and the experimental measurements when Young's modulus for skull and polyurethane was set to be 7.3 GPa and 1 MPa with 0.01 and 0.1 loss factors at 1 kHz, respectively. Moreover, the acceleration in the medial-lateral direction showed the best correspondence with the published experimental data, whereas the acceleration in the inferior-superior direction showed the largest discrepancy. However, the results were reasonable considering that different geometries were used for the 3D FE skull and the skull used in the published experimental study. The dry skull model is a first step for understanding BC hearing mechanism in a human head and simulation results can be used to predict vibration pattern of the bone surrounding the middle and inner ear during BC stimulation. PMID:25243148

  12. MARGA: multispectral adaptive region growing algorithm for brain extraction on axial MRI.

    PubMed

    Roura, Eloy; Oliver, Arnau; Cabezas, Mariano; Vilanova, Joan C; Rovira, Alex; Ramió-Torrentà, Lluís; Lladó, Xavier

    2014-02-01

    Brain extraction, also known as skull stripping, is one of the most important preprocessing steps for many automatic brain image analysis. In this paper we present a new approach called Multispectral Adaptive Region Growing Algorithm (MARGA) to perform the skull stripping process. MARGA is based on a region growing (RG) algorithm which uses the complementary information provided by conventional magnetic resonance images (MRI) such as T1-weighted and T2-weighted to perform the brain segmentation. MARGA can be seen as an extension of the skull stripping method proposed by Park and Lee (2009) [1], enabling their use in both axial views and low quality images. Following the same idea, we first obtain seed regions that are then spread using a 2D RG algorithm which behaves differently in specific zones of the brain. This adaptation allows to deal with the fact that middle MRI slices have better image contrast between the brain and non-brain regions than superior and inferior brain slices where the contrast is smaller. MARGA is validated using three different databases: 10 simulated brains from the BrainWeb database; 2 data sets from the National Alliance for Medical Image Computing (NAMIC) database, the first one consisting in 10 normal brains and 10 brains of schizophrenic patients acquired with a 3T GE scanner, and the second one consisting in 5 brains from lupus patients acquired with a 3T Siemens scanner; and 10 brains of multiple sclerosis patients acquired with a 1.5T scanner. We have qualitatively and quantitatively compared MARGA with the well-known Brain Extraction Tool (BET), Brain Surface Extractor (BSE) and Statistical Parametric Mapping (SPM) approaches. The obtained results demonstrate the validity of MARGA, outperforming the results of those standard techniques. PMID:24380649

  13. Talus fractures: surgical principles.

    PubMed

    Rush, Shannon M; Jennings, Meagan; Hamilton, Graham A

    2009-01-01

    Surgical treatment of talus fractures can challenge even the most skilled foot and ankle surgeon. Complicated fracture patterns combined with joint dislocation of variable degrees require accurate assessment, sound understanding of principles of fracture care, and broad command of internal fixation techniques needed for successful surgical care. Elimination of unnecessary soft tissue dissection, a low threshold for surgical reduction, liberal use of malleolar osteotomy to expose body fracture, and detailed attention to fracture reduction and joint alignment are critical to the success of treatment. Even with the best surgical care complications are common and seem to correlate with injury severity and open injuries. PMID:19121756

  14. Radiology of Fractures in Intoxicated Emergency Department Patients: Locations, Mechanisms, Presentation, and Initial Interpretation Accuracy

    PubMed Central

    Morita, Yuka; Nozaki, Taiki; Starkey, Jay; Okajima, Yuka; Ohde, Sachiko; Matsusako, Masaki; Yoshioka, Hiroshi; Saida, Yukihisa; Kurihara, Yasuyuki

    2015-01-01

    Abstract The purpose of this study was to investigate the relationship of alcohol intoxication to time-to-presentation following injury, fracture type, mechanism of injury leading to fracture, and initial diagnostic radiology interpretation performance of emergency physicians versus diagnostic radiologists in patients who present to the emergency department (ED) and are subsequently diagnosed with fracture. Medical records of 1286 patients who presented to the ED and were diagnosed with fracture who also underwent plain film or computed tomography (CT) imaging were retrospectively reviewed. The subjects were divided into intoxicated and sober groups. Patient characteristics, injury-to-presentation time, fracture location, and discrepancies between initial clinical and radiological evaluations were compared. Of 1286 subjects, 181 patients were included in the intoxicated group. Only intoxicated patients presented with head/neck fractures more than 24 hours after injury. The intoxicated group showed a higher rate of head/neck fractures (skull 23.2% vs 5.8%, face and orbit 30.4% vs 9.5%; P < 0.001) and a lower rate of extremity injuries. The rate of nondiagnosis of fractures by emergency physicians later identified by radiologists was the same in both groups (7.7% vs 7.7%, P = 0.984). While the same proportion of intoxicated patients presented more than 24 hours following injury, only intoxicated patients presented with craniofacial and cervical spinal fractures during this period. Alcohol-related injuries are more often associated with head/neck fractures but less extremity injuries. The rate of fractures missed by emergency physicians but later diagnosed by radiologists was the same in intoxicated and sober patients.

  15. Patterns of skeletal fractures in child abuse: systematic review

    PubMed Central

    Dunstan, Frank; Harrison, Sara; Morris, Susan; Mann, Mala; Rolfe, Kim; Datta, Shalini; Thomas, D Phillip; Sibert, Jonathan R; Maguire, Sabine

    2008-01-01

    to be inflicted. For femoral fractures, the probability was between 0.28 (0.15 to 0.44) and 0.43 (0.32 to 0.54), depending on the definition of abuse used, and the developmental stage of the child was an important discriminator. The probability for skull fractures was 0.30 (0.19 to 0.46); the most common fractures in abuse and non-abuse were linear fractures. Insufficient comparative studies were available to allow calculation of a probability of abuse for other fracture types. Conclusion When infants and toddlers present with a fracture in the absence of a confirmed cause, physical abuse should be considered as a potential cause. No fracture, on its own, can distinguish an abusive from a non-abusive cause. During the assessment of individual fractures, the site, fracture type, and developmental stage of the child can help to determine the likelihood of abuse. The number of high quality comparative research studies in this field is limited, and further prospective epidemiology is indicated. PMID:18832412

  16. Epidemiology of clavicle fractures.

    PubMed

    Postacchini, Franco; Gumina, Stefano; De Santis, Pierfrancesco; Albo, Francesco

    2002-01-01

    An epidemiologic study of 535 isolated clavicle fractures treated in a hospital of a large metropolis during an 11-year period was performed. Data regarding patient's age and sex, side involved, mechanism of injury, and season in which the fracture occurred were obtained from the clinical records. Radiographic classification was performed with the Allman system. Clavicle fractures represented 2.6% of all fractures and 44% of those in the shoulder girdle. Most patients were men (68%), and the left side was involved in 61% of cases. Fractures of the middle third of the clavicle, which were the most common (81%), were displaced in 48% of cases and comminuted in 19%. Fractures of the medial third were the least common (2%). The prevalence of midclavicular fractures was found to decrease progressively with age, starting from the first decade of life when they represented 88.2% of all clavicle fractures and were undisplaced in 55.5% of cases. In adults, the incidence of displaced fractures, independent of location, was higher than that of undisplaced fractures. Traffic accidents were the most common cause of the injury. In the period under study, the incidence of fractures showed no significant change over time and no seasonal variation. PMID:12378163

  17. Mechanics of Hydraulic Fractures

    NASA Astrophysics Data System (ADS)

    Detournay, Emmanuel

    2016-01-01

    Hydraulic fractures represent a particular class of tensile fractures that propagate in solid media under pre-existing compressive stresses as a result of internal pressurization by an injected viscous fluid. The main application of engineered hydraulic fractures is the stimulation of oil and gas wells to increase production. Several physical processes affect the propagation of these fractures, including the flow of viscous fluid, creation of solid surfaces, and leak-off of fracturing fluid. The interplay and the competition between these processes lead to multiple length scales and timescales in the system, which reveal the shifting influence of the far-field stress, viscous dissipation, fracture energy, and leak-off as the fracture propagates.

  18. The Hydraulic Mechanism in the Orbital Blowout Fracture Because of a High-Pressure Air Gun Injury.

    PubMed

    Kang, Seok Joo; Chung, Eui Han

    2015-10-01

    There are 2 predominant mechanisms that are used to explain the pathogenesis of orbital blowout fracture; these include hydraulic and buckling mechanisms. Still, however, its pathophysiology remains uncertain. To date, studies in this series have been conducted using dry skulls, cadavers, or animals. But few clinical studies have been conducted to examine whether the hydraulic mechanism is involved in the occurrence of pure orbital blowout fracture. The authors experienced a case of a 52-year-old man who had a pure medial blowout fracture after sustaining an eye injury because of a high-pressure air gun. Our case suggests that surgeons should be aware of the possibility that the hydraulic mechanism might be involved in the blowout fracture in patients presenting with complications, such as limitation of eye movement, diplopia, and enophthalmos. PMID:26468824

  19. Sociology: The growing climate divide

    NASA Astrophysics Data System (ADS)

    Hoffman, Andrew J.

    2011-07-01

    Climate change has reached the level of a 'scientific consensus', but is not yet a 'social consensus'. New analysis highlights that a growing divide between liberals and conservatives in the American public is a major obstacle to achieving this end.

  20. Birth of space plant growing

    NASA Technical Reports Server (NTRS)

    Mashinskiy, A.; Nechitaylo, G.

    1983-01-01

    The attempts, and successes, to grow plants in space, and get them to fully develop, bloom and produce seeds using orchids are presented. The psychological advantages of the presence of plants onboard space vehicles and space stations is indicated.

  1. Beringian Megafaunal Extinctions at ~37 ka B.P.: Do Micrometeorites Embedded in Fossil Tusks and Skulls Indicate an Extraterrestial Precursor to the Younger Dryas Event?

    NASA Astrophysics Data System (ADS)

    Hagstrum, J. T.; Firestone, R. B.; West, A.

    2009-12-01

    Studies of Late Pleistocene megafaunal fossils and their ancient DNA from Beringia (eastern Siberia, Alaska, and the emerged Bering Strait) indicate sharp declines in steppe bison population diversity and horse body size, extinction of the Alaskan wild ass, and local extinctions of brown bear and woolly mammoth genetic lines beginning at about 37 ka B.P. Beringia is also well known for its remarkably preserved Late Pleistocene frozen animal mummies. 14C ages of these mummies are bimodally distributed, having peaks coincident with the earlier ~37 ka B.P., and ~13 ka B.P. Younger Dryas, onset extinction events. Associated with the ~37 ka B.P. event are, for example, the Berezovka mammoth, headless Selerikan horse, steppe bison “Blue Babe”, and baby mammoths “Dima” and “Lyuba”. Analyses of these and other mummies indicate that they died instantly, in mostly healthy condition, with gut contents and high fat reserves indicative of a late summer to autumn season. An assortment of uneaten limbs and other body parts from a variety of species have also been found. Uniformitarian death scenarios inadequately account for the lack of evidence of normal predation and scavenging. Extensive internal injuries (e.g. large bone fractures, hemorrhaging) and apparent rapid burial of the mummies also indicate that something truly unusual happened at the time of these extinction events. We have discovered what appear to be micrometeorites embedded in seven Alaskan mammoth tusks and a Siberian bison skull acquired from commercial sources. 14C ages for five of these fossils have a weighted mean age of 33 ± 2 ka B.P. Laser ablation ICP-MS and XRF analyses of the particles indicate high Fe contents with compositions enriched in Ni and depleted in Ti, similar to Fe meteorites and unlike any natural terrestrial sources. Microprobe analyses of a Fe-Ni sulfide grain from tusk 2 also show that it contains between 3 and 20 weight percent Ni. SEM images and XRF analyses of a bison

  2. Modeling of Interaction of Hydraulic Fractures in Complex Fracture Networks

    NASA Astrophysics Data System (ADS)

    Kresse, O. 2; Wu, R.; Weng, X.; Gu, H.; Cohen, C.

    2011-12-01

    A recently developed unconventional fracture model (UFM) is able to simulate complex fracture network propagation in a formation with pre-existing natural fractures. Multiple fracture branches can propagate at the same time and intersect/cross each other. Each open fracture exerts additional stresses on the surrounding rock and adjacent fractures, which is often referred to as "stress shadow" effect. The stress shadow can cause significant restriction of fracture width, leading to greater risk of proppant screenout. It can also alter the fracture propagation path and drastically affect fracture network patterns. It is hence critical to properly model the fracture interaction in a complex fracture model. A method for computing the stress shadow in a complex hydraulic fracture network is presented. The method is based on an enhanced 2D Displacement Discontinuity Method (DDM) with correction for finite fracture height. The computed stress field is compared to 3D numerical simulation in a few simple examples and shows the method provides a good approximation for the 3D fracture problem. This stress shadow calculation is incorporated in the UFM. The results for simple cases of two fractures are presented that show the fractures can either attract or expel each other depending on their initial relative positions, and compares favorably with an independent 2D non-planar hydraulic fracture model. Additional examples of both planar and complex fractures propagating from multiple perforation clusters are presented, showing that fracture interaction controls the fracture dimension and propagation pattern. In a formation with no or small stress anisotropy, fracture interaction can lead to dramatic divergence of the fractures as they tend to repel each other. However, when stress anisotropy is large, the fracture propagation direction is dominated by the stress field and fracture turning due to fracture interaction is limited. However, stress shadowing still has a strong effect

  3. Surgical anatomy and utility of pedicled vascularized tissue flaps for multilayered repair of skull base defects.

    PubMed

    Safavi-Abbasi, Sam; Komune, Noritaka; Archer, Jacob B; Sun, Hai; Theodore, Nicholas; James, Jeffrey; Little, Andrew S; Nakaji, Peter; Sughrue, Michael E; Rhoton, Albert L; Spetzler, Robert F

    2016-08-01

    OBJECT The objective of this study was to describe the surgical anatomy and technical nuances of various vascularized tissue flaps. METHODS The surgical anatomy of various tissue flaps and their vascular pedicles was studied in 5 colored silicone-injected anatomical specimens. Medical records were reviewed of 11 consecutive patients who underwent repair of extensive skull base defects with a combination of various vascularized flaps. RESULTS The supraorbital, supratrochlear, superficial temporal, greater auricular, and occipital arteries contribute to the vascular supply of the pericranium. The pericranial flap can be designed based on an axial blood supply. Laterally, various flaps are supplied by the deep or superficial temporal arteries. The nasoseptal flap is a vascular pedicled flap based on the nasoseptal artery. Patients with extensive skull base defects can undergo effective repair with dual flaps or triple flaps using these pedicled vascularized flaps. CONCLUSIONS Multiple pedicled flaps are available for reconstitution of the skull base. Knowledge of the surgical anatomy of these flaps is crucial for the skull base surgeon. These vascularized tissue flaps can be used effectively as single or combination flaps. Multilayered closure of cranial base defects with vascularized tissue can be used safely and may lead to excellent repair outcomes. PMID:26613175

  4. Management of Anterior Skull Base Defect Depending on Its Size and Location

    PubMed Central

    Bernal-Sprekelsen, Manuel; Rioja, Elena; Enseñat, Joaquim; Enriquez, Karla; Viscovich, Liza; Agredo-Lemos, Freddy Enrique; Alobid, Isam

    2014-01-01

    Introduction. We present our experience in the reconstruction of these leaks depending on their size and location. Material and Methods. Fifty-four patients who underwent advanced skull base surgery (large defects, >20 mm) and 62 patients with CSF leaks of different origin (small, 2–10 mm, and midsize, 11–20 mm, defects) were included in the retrospective study. Large defects were reconstructed with a nasoseptal pedicled flap positioned on fat and fascia lata. In small and midsized leaks. Fascia lata in an underlay position was used for its reconstruction covered with mucoperiosteum of either the middle or the inferior turbinate. Results. The most frequent etiology for small and midsized defects was spontaneous (48.4%), followed by trauma (24.2%), iatrogenic (5%). The success rate after the first surgical reconstruction was 91% and 98% in large skull base defects and small/midsized, respectively. Rescue surgery achieved 100%. Conclusions. Endoscopic surgery for any type of skull base defect is the gold standard. The size of the defects does not seem to play a significant role in the success rate. Fascia lata and mucoperiosteum of the turbinate allow a two-layer reconstruction of small and midsized defects. For larger skull base defects, a combination of fat, fascia lata, and nasoseptal pedicled flaps provides a successful reconstruction. PMID:24895567

  5. Cranial Suture Closure in Domestic Dog Breeds and Its Relationships to Skull Morphology.

    PubMed

    Geiger, Madeleine; Haussman, Sinah

    2016-04-01

    Bulldog-type brachycephalic domestic dog breeds are characterized by a relatively short and broad skull with a dorsally rotated rostrum (airorhynchy). Not much is known about the association between a bulldog-type skull conformation and peculiar patterns of suture and synchondrosis closure in domestic dogs. In this study, we aim to explore breed-specific patterns of cranial suture and synchondrosis closure in relation to the prebasial angle (proxy for airorhynchy and thus bulldog-type skull conformation) in domestic dogs. For this purpose, we coded closure of 18 sutures and synchondroses in 26 wolves, that is, the wild ancestor of all domestic dogs, and 134 domestic dogs comprising 11 breeds. Comparisons of the relative amount of closing and closed sutures and synchondroses (closure scores) in adult individuals showed that bulldog-type breeds have significantly higher closure scores than non-bulldog-type breeds and that domestic dogs have significantly higher closure scores than the wolf. We further found that the prebasial angle is significantly positively correlated with the amount of closure of the basispheno-presphenoid synchondrosis and sutures of the nose (premaxillo-nasal and maxillo-nasal) and the palate (premaxillo-maxillary and interpalatine). Our results show that there is a correlation between patterns of suture and synchondrosis closure and skull shape in domestic dogs, although the causal relationships remain elusive. Anat Rec, 299:412-420, 2016. © 2016 Wiley Periodicals, Inc. PMID:26995336

  6. Morphologic and Osteometric Analysis of the Skull of Markhoz Goat (Iranian Angora)

    PubMed Central

    Goodarzi, Nader; Shah Hoseini, Toraj

    2014-01-01

    This study provides some comprehensive osteometric and morphologic descriptions of the skull region of the Markhoz goat. Totally, 17 osteometric parameters of eight skulls of Markhoz goat were measured and expressed as mean ± SD. A skull length of 18.67 ± 0.66, a cranial length of 11.1 ± 0.38, a facial length of 10.23 ± 0.76, a skull index of 47.77 ± 1.96, a cranial index of 54.04 ± 2.29, a facial index of 100.77 ± 6.85 and a foramen magnum index of 89.32 ± 14.1 were recorded. Morphologically frontal bone did not constitute the caudal extent of frontal surface; rather it was formed by the parietal bone. There were two supraorbital foramina in both sides. The prominent facial tuberosity lies dorsally to the 3rd cheek tooth. The infraorbital foramen was single on either side which was located directly dorsally to the junction of the first and second upper premolar. The orbits were round and complete and located on a frontolateral oblique plane. The basilar part of the occipital bone was surrounded by two pairs of muscular tubercles with similar size. The temporal line was continuous of the temporal crest and ran over the parietal bone. In conclusion, the morphologic and osteometric data of Markhoz goat are comparable to other ruminants. PMID:24955281

  7. The Mystery of the Skulls: What Can Old Bones Tell Us about Hominin Evolution?

    ERIC Educational Resources Information Center

    Yerky, Mike Darwin; Wilczynski, Carolyn J.

    2014-01-01

    In this activity, students examine nine hominin skulls for specialized features and take measurements that will enable them to determine the relatedness of these species. They will ultimately place each specimen on a basic phylogenetic tree that also reveals the geological time frame in which each species lived. On the basis of their data, and…

  8. Real-time determination of skull thickness for a manually-navigated synergistic trepanation tool.

    PubMed

    Korff, Alexander; Follmann, Axel; Winter, Lukas; de la Fuente, Matias; Schmieder, Kirsten; Radermacher, Klaus

    2010-01-01

    Trepanation of the skull is a common procedure in neurosurgery with the problems of dural tears and wide cutting gaps. A hand-guided instrument containing a soft-tissue preserving saw whose cutting depth is automatically adapted on the basis of a-priori data (CT, MRI) is envisioned to reduce these problems. PMID:21096796

  9. Phenotypic plasticity in skull and dental morphology in the prairie deer mouse (Peromyscus maniculatus bairdii).

    PubMed

    Myers, P; Lundrigan, B L; Gillespie, B W; Zelditch, M L

    1996-08-01

    Morphologists and systematists have long suspected that dietary consistency can affect skull and dental form in mammals. We examined plasticity of skull shape and tooth morphology in prairie deer mice (Peromyscus maniculatus bairdii) by feeding mice diets that differed in consistency but not nutritional quality. Shape differences were analyzed qualitatively and quantitatively, using both landmark-based morphometrics and traditional distance measurements. Mice fed a gruel made of laboratory chow soaked in water differed from those fed hard blocks of chow by a slight anterior shift in the incisor tips, a narrowed zygomatic plate, a reduction in size of the masseteric tubercles, an overall decrease in skull size in lateral view, and an increase in overall size in ventral view. Disparities between our results and previous studies may be due to the differences in behavior between the inbred, relatively inactive laboratory strains commonly used in experimental studies and the outbred, constantly active species used here. Also, in contrast to previous studies, the statistical analysis employed here took into account both family relationships of the animals and the large number of statistical comparisons performed. Failure to consider these factors would have resulted in an exaggerated estimate of the effects of diet on skull form and may taint other studies that have explored the same aspects of plasticity. PMID:8755340

  10. Symmetrical osteoporosis (spongy hyperostosis) in a prehistoric skull from New Mexico.

    PubMed

    Jarcho, S; Simon, N; Jaffe, H L

    1965-01-01

    Fragments of an Anasazi skull (Pueblo II-III) from New Mexico are described. Lesions of symmetrical osteoporosis were found and their anatomical and roentgenographic characteristics are discussed. The term symmetrical osteoporosis has led to confusion with the unrelated disease osteoporosis and should be replaced by the designation spongy hyperostosis. PMID:19588580

  11. Effect of skull resistivity on the spatial resolutions of EEG and MEG.

    PubMed

    Malmivuo, Jaakko A; Suihko, Veikko E

    2004-07-01

    The resistivity values of the different tissues of the head affect the lead fields of electroencephalography (EEG). When the head is modeled with a concentric spherical model, the different resistivity values have no effect on the lead fields of the magnetoencephalography (MEG). Recent publications indicate that the resistivity of the skull is much lower than what was estimated by Rush and Driscoll. At the moment, this information on skull resistivity is, however, slightly controversial. We have compared the spatial resolution of EEG and MEG for cortical sources by calculating the half-sensitivity volumes (HSVs) of EEG and MEG as a function of electrode and magnetometer distance, respectively, with the relative skull resistivity as a parameter. Because the spatial resolution is related to the HSV, these data give an overview of the effect of these parameters on the spatial resolution of both techniques. Our calculations show that, with the new information on the resistivity of the skull, in the spherical model for cortical sources the spatial resolution of the EEG is better than that of the MEG. PMID:15248545

  12. A COMPARISON OF SKULL AND FEMUR LEAD LEVELS IN ADULT RATS

    EPA Science Inventory

    The purpose of the study was to elucidate the relationship between skull and femur lead levels in laboratory rats. Forty-eight female rats were given one of four lead chloride drinking water solutions: 0.05, 0.58, 17, or 352 ppm lead. Two animals from each group were sacrificed a...

  13. Harvey Cushing's Treatment of Skull Base Infections: The Johns Hopkins Experience

    PubMed Central

    Somasundaram, Aravind; Pendleton, Courtney; Raza, Shaan M.; Boahene, Kofi; Quinones-Hinojosa, Alfredo

    2012-01-01

    Objectives In this report, we review Dr. Cushing's early surgical cases at the Johns Hopkins Hospital, revealing details of his early operative approaches to infections of the skull base. Design Following institutional review board (IRB) approval, and through the courtesy of the Alan Mason Chesney Archives, we reviewed the Johns Hopkins Hospital surgical files from 1896 to 1912. Setting The Johns Hopkins Hospital, 1896 to 1912. Participants Eleven patients underwent operative treatment for suspected infections 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 Eleven patients underwent operative intervention for infections of the skull base. The mean age was 30 years (range: 9 to 63). Of these patients, seven (64%) were female. The mean length of stay was 16.5 days (range: 4 to 34). Postoperatively eight patients were discharged in “well” or “good” condition, one patient remained “unimproved,” and two patients died during their admission. Conclusion Cushing's careful preoperative observation of patients, meticulous operative technique, and judicious use of postoperative drainage catheters contributed to a remarkably low mortality rate in his series of skull base infections. PMID:24083129

  14. A rare case of atypical skull base meningioma with perineural spread

    PubMed Central

    Walton, Henry; Morley, Simon; Alegre-Abarrategui, Javier

    2015-01-01

    Atypical meningioma is a rare cause of perineural tumour spread. In this report, we present the case of a 46-year-old female with an atypical meningioma of the skull base demonstrating perineural tumour spread. We describe the imaging features of this condition and its distinguishing features from other tumours exhibiting perineural spread. PMID:27200171

  15. Upper Elementary Students Creatively Learn Scientific Features of Animal Skulls by Making Movable Books

    ERIC Educational Resources Information Center

    Klein, Julie L.; Gray, Phyllis; Zhbanova, Ksenia S.; Rule, Audrey C.

    2015-01-01

    Arts integration in science has benefits of increasing student engagement and understanding. Lessons focusing on form and function of animal skulls provide an effective example of how handicrafts integrated with science instruction motivate students and support learning. The study involved students ages 9-12 during a week-long summer day camp.…

  16. Waveform analysis of aftershocks of the June 29, 1992 Little Skull Mountain, Nevada, earthquake

    SciTech Connect

    Sheehan, A.F.; Zeng, Y.; Smith, K.D. )

    1993-04-01

    Following the 29 June 1992 magnitude 5.6 Little Skull Mountain, Nevada, earthquake, twelve portable three-component digital seismometers were deployed in the region surrounding Little Skull Mountain and Yucca Mountain by researchers at the University of Nevada, Reno, Seismological Laboratory. These stations complemented the 55 permanent analog stations of the Southern Great Basin Seismic Network, and portable deployments of the United States Geological Survey (USGS), Golden, Colorado, and Lawrence Livermore National Laboratory, Livermore, California. The mainshock of the Little Skull Mountain earthquake occurred approximately 20 km southeast of the site at Yucca Mountain, Nevada, that is being characterized as a potential repository for high-level nuclear waste. The pattern of Little Skull Mountain aftershocks defines an L' shape at the southern boundary of the Nevada Test Site. The authors use a full waveform inversion method to study source properties of aftershocks in the epicentral area recorded on the digital stations. They compute the synthetic seismograms in a layered elastic media using the generalized reflection and transmission coefficient technique. The authors future plans include automation of these techniques for use in routine monitoring of seismic activity in the region. Parameters obtained in this study include focal mechanism, stress drop, rupture duration, and seismic moment. These results will allow them to place constraints on the geometry and style of subsurface faulting in the region and aid in the assessment of seismic hazard in the vicinity of Yucca Mountain.

  17. Amphibian skull evolution: the developmental and functional context of simplification, bone loss and heterotopy.

    PubMed

    Schoch, Rainer R

    2014-12-01

    Despite their divergent morphology, extant and extinct amphibians share numerous features in the timing and spatial patterning of dermal skull elements. Here, I show how the study of these features leads to a deeper understanding of morphological evolution. Batrachians (salamanders and frogs) have simplified skulls, with dermal bones appearing rudimentary compared with fossil tetrapods, and open cheeks resulting from the absence of other bones. The batrachian skull bones may be derived from those of temnospondyls by truncation of the developmental trajectory. The squamosal, quadratojugal, parietal, prefrontal, parasphenoid, palatine, and pterygoid form rudimentary versions of their homologs in temnospondyls. In addition, failure to ossify and early fusion of bone primordia both result in the absence of further bones that were consistently present in Paleozoic tetrapods. Here, I propose a new hypothesis explaining the observed patterns of bone loss and emargination in a functional context. The starting observation is that jaw-closing muscles are arranged in a different way than in ancestors from the earliest ontogenetic stage onwards, with muscles attaching to the dorsal side of the frontal, parietal, and squamosal. The postparietal and supratemporal start to ossify in a similar way as in branchiosaurids, but are fused to neighboring elements to form continuous attachment areas for the internal adductor. The postfrontal, postorbital, and jugal fail to ossify, as their position is inconsistent with the novel arrangement of adductor muscles. Thus, rearrangement of adductors forms the common theme behind cranial simplification, driven by an evolutionary flattening of the skull in the batrachian stem. PMID:25404554

  18. Transnasal illumination to guide the craniofacial resection of anterior skull base neoplasms.

    PubMed

    Cohen, A R; Tartell, P B

    1993-11-01

    The authors describe use of a flexible fiberoptic light source to guide the craniofacial resection of anterior skull base neoplasms. The light is introduced transnasally and serves to outline the perimeter of the tumor, helping to direct the safe placement of intracranial osteotomies and en bloc tumor removal. PMID:8211661

  19. Fracture corridors in carbonates

    NASA Astrophysics Data System (ADS)

    Chatelée, Sébastien; Lamarche, Juliette; Gauthier, Bertrand D. M.

    2015-04-01

    Among fractures, Fracture Corridors (FC) are anomalous structures made of highly persistent fracture clusters having a strong effect on multi-phase fluid flow in the subsurface. While mechanical and geological conditions for diffuse fracture systems are well constrained, FC genetic conditions remain a matter of questioning. FC can be localized in larger structures such as folds and fault zones but recent studies suggest that a large amount of fractures and FC also arise as distributed in the host rock and formed in tabular layers during burial with early rock mechanical differentiation. In addition, while the mechanical stratigraphy is of prime importance for fracture stratigraphy, it is still unknown which factor prevails on FC genesis among the local versus regional stress-state, the host rock mechanical stratigraphy or the sedimentary facies. We present a study of fractures in a 400×300 m wide quarry (Calvisson, SE France) dug in homogeneous marly limestones of Hauterivian age. The quarry exhibits diffuse fractures as well as 16 FC. The aim of this study is to reveal the genetics factor for FC development, their global geometry and internal morphologic variations, but also to clear the impact of fracture corridors on diffuse fracture. For that, we measured >2500 fractures (strike, dip, spacing, filling, aperture, etc.) and studied microstructures in 80 thin sections. We calculated fracture density and acquired LiDAR data with >90 million points with a resolution of 4 to 15mm. Diffuse fractures are organized as two perpendicular sets, a main set NE-SW-trending and minor set NW-SE-trending. The FC have the same trend, but the NW-SE trend prevail on the NE-SW one. The LiDAR acquisition allows to visualize the 3D lateral continuity with corridors with a minimal extension of 30m. We distinguish 4 internal morphologic types in FC, depending on fracture morphology, occurrence of breccia and number of zones. The types may occur in a single FC with a lateral transition

  20. Stress fractures in athletes.

    PubMed

    Hulkko, A; Orava, S

    1987-06-01

    During the 14-year period of 1971-1985, 368 stress fractures in 324 athletes were treated. The series contained 268 fractures in males and 100 fractures in females; 32 fractures occurred in children (less than 16 years), 117 in adolescents (16-19 years), and 219 in adults. Forty-six fractures were incurred by athletes at an international level, 274 by athletes at a national or district level and 48 by recreational athletes. Of the total cases, 72% occurred to runners and a further 12% to athletes in other sports after running exercises. The distribution of the stress fractures by site was: tibia 182, metatarsal bones 73, fibula 44, big toe sesamoid bones 15, femoral shaft 14, femoral neck 9, tarsal navicular 9, pelvis 7, olecranon 5 and other bones 10. Of the total fractures, 342 were treated conservatively and 26 fractures required surgical treatment. The operative indication was dislocation in 5 cases and delayed union/nonunion in 21 cases. The sites most often affected by delayed union were: anterior midtibia, sesamoid bones of the big toe, base of the fifth metatarsal, olecranon, and tarsal navicular. The athletes at an international level experienced the greatest risk of multiple separate fractures, protracted healing, or fractures requiring surgery. PMID:3623785

  1. Experience in charged particle irradiation of tumors of the skull base

    SciTech Connect

    Castro, J.R.; Linstadt, D.E.; Bahary, J.P.; Petti, P.L.; Daftari, I. Collier, J.M.; Gutin, P.H.; Gauger, G.; Phillips, T.L.

    1994-07-01

    The purpose was to review the experience at University of California Lawrence Berkeley Laboratory in using charged particles to irradiate primary neoplasms of the skull base and those extending to the skull base from the nasopharynx and paranasal sinuses. During the period from 1977 to 1992, 223 patients were irradiated with charged particles at the Lawrence Berkeley Laboratory for tumors either arising in or extending to the skull base, of whom 48 (22%) had recurrent lesions, either post previous surgery or radiotherapy. One hundred twenty-six patients had lesions arising in the cranial base, mostly chordoma (53), chondrosarcoma (27), paraclival meningioma (27) with 19 patients having other histologies such as osteosarcoma or neurofibrosarcoma. There were also 31 patients with primary or recurrent squamous carcinoma of the nasopharynx extending to the skull base, 44 patients with major or minor salivary gland tumors, mostly adenocarcinoma, and 22 patients with squamous carcinoma of the paranasal sinuses, all with cranial base extension. Local control and survival appeared improved in tumors arising in the skull base, following the ability with charged particles to deliver high doses (mean of 65 GY-equivalent) with relative sparing of the adjacent normal tissues. The Kaplan-Meier 5-year local control was 85% for meningioma, 78% for chondrosarcoma, 63% for chordoma and 58% for other sarcoma. Follow-up ranged from 4-191 months with a median of 51 months. Charged particle radiotherapy is highly effective in controlling cranial base lesions which have been partially resected. Better tumor localization with CT and MRI, improved 3-D treatment planning and beam delivery techniques have continued to reduce the level of serious complications and increase local control and survival. 35 refs., 4 figs., 8 tabs.

  2. Aspects of achondroplasia in the skulls of dwarf transgenic mice: a cephalometric study.

    PubMed

    Bloom, Melissa Wadler; Murakami, Shunichi; Cody, Dianna; Montufar-Solis, Dina; Duke, Pauline Jackie

    2006-03-01

    Achondroplasia, the most common short-limbed dwarfism in humans, results from a single nucleotide substitution in the gene for fibroblast growth factor receptor 3 (FGFR3). FGFR3 regulates bone growth in part via the mitogen-activated protein kinase pathway (MAPK). To examine the role of this pathway in chondrocyte differentiation, a transgenic mouse was generated that expresses a constitutively active mutant of MEK1 in chondrocytes and exhibits dwarfing characteristics typical of human achondroplasia, i.e., shortened axial and appendicular skeletons, mid-facial hypoplasia, and dome-shaped cranium. In this study, cephalometrics of the MEK1 mutant skulls were assessed to determine if the MEK1 mice are a good model of achondroplasia. Skull length, arc of the cranial vault, and area, maximum and minimum diameters of the brain case were measured on digitized radiographs of skulls of MEK1 and control mice. Cranial base and nasal bone length and foramen magnum diameter were measured on midsagittal micro-CT sections. Data were normalized by dividing by the cube root of each animal's weight. Transgenic mice exhibited a domed skull, deficient midface, and (relatively) prognathic mandible and had a shorter cranial base and nasal bone than the wild-type. Skull length was significantly less in transgenic mice, but cranial arc was significantly greater. The brain case was larger and more circular and minimum diameter of the brain case was significantly greater in transgenic mice. The foramen magnum was displaced anteriorly but not narrowed. MEK1 mouse cephalometrics confirm these mice as a model for achondroplasia, demonstrating that the MAP kinase signaling pathway is involved in FGF signaling in skeletal development. PMID:16463380

  3. Comparative Skull Analysis Suggests Species-Specific Captivity-Related Malformation in Lions (Panthera leo)

    PubMed Central

    Saragusty, Joseph; Shavit-Meyrav, Anat; Yamaguchi, Nobuyuki; Nadler, Rona; Bdolah-Abram, Tali; Gibeon, Laura; Hildebrandt, Thomas B.; Shamir, Merav H.

    2014-01-01

    Lion (Panthera leo) populations have dramatically decreased worldwide with a surviving population estimated at 32,000 across the African savannah. Lions have been kept in captivity for centuries and, although they reproduce well, high rates of stillbirths as well as morbidity and mortality of neonate and young lions are reported. Many of these cases are associated with bone malformations, including foramen magnum (FM) stenosis and thickened tentorium cerebelli. The precise causes of these malformations and whether they are unique to captive lions remain unclear. To test whether captivity is associated with FM stenosis, we evaluated 575 lion skulls of wild (N = 512) and captive (N = 63) origin. Tiger skulls (N = 276; 56 captive, 220 wild) were measured for comparison. While no differences were found between males and females or between subadults and adults in FM height (FMH), FMH of captive lions (17.36±3.20 mm) was significantly smaller and with greater variability when compared to that in wild lions (19.77±2.11 mm). There was no difference between wild (18.47±1.26 mm) and captive (18.56±1.64 mm) tigers in FMH. Birth origin (wild vs. captive) as a factor for FMH remained significant in lions even after controlling for age and sex. Whereas only 20/473 wild lions (4.2%) had FMH equal to or smaller than the 5th percentile of the wild population (16.60 mm), this was evident in 40.4% (23/57) of captive lion skulls. Similar comparison for tigers found no differences between the captive and wild populations. Lions with FMH equal to or smaller than the 5th percentile had wider skulls with smaller cranial volume. Cranial volume remained smaller in both male and female captive lions when controlled for skull size. These findings suggest species- and captivity-related predisposition for the pathology in lions. PMID:24718586

  4. The Flap Sandwich Technique for a Safe and Aesthetic Skull Base Reconstruction.

    PubMed

    Yano, Tomoyuki; Okazaki, Mutsumi; Tanaka, Kentarou; Iida, Hideo

    2016-02-01

    For safe and reliable skull base reconstruction combined with repair of cranial bone defects, we introduce the flap sandwich technique in this study. A titanium mesh is often used to repair structural cranial bone defects because it has less donor site morbidity and is easy to handle. However, titanium mesh has disadvantages of exposure and infection postoperatively. To improve surgical outcomes, we applied the flap sandwich technique to 3 cases of skull base reconstruction combined with cranial bone defect repair. Two anterior skull base defects and 1 middle skull base defect were included in this study. The subjects were all women, aged 30, 58, and 62 years. One patient had former multiple craniotomies and another patient had preoperative radiotherapy. The flap sandwich technique involves structural cranial bone reconstruction with a titanium mesh and soft tissue reconstruction with a chimeric anterolateral thigh free flap. First, the dead space between the repaired dura and the titanium mesh is filled with vastus lateralis muscle, and then structural reconstruction is performed with a titanium mesh. Finally, the titanium mesh is totally covered with the adiposal flap of the anterolateral thigh free flap. The muscle flap protects the dead space from infection, and the adiposal flap covers the titanium mesh to reduce mechanical stress on the covered skin and thus prevent the exposure of the titanium mesh through the scalp. By applying this technique, there was no intracranial infection or titanium mesh exposure in these 3 cases postoperatively, even though 2 patients had postoperative radiotherapy. Additionally, the adiposal flap could provide a soft and natural contour to the scalp and forehead region, and this gives patients a better facial appearance even though they have had skull base surgery. PMID:25954846

  5. A discussion of current issues and concepts in the practice of skull-photo/craniofacial superimposition.

    PubMed

    Gordon, G M; Steyn, M

    2016-05-01

    A recent review paper on cranio-facial superimposition (CFS) stated that "there have been specific conceptual variances" from the original methods used in the practice of skull-photo superimposition, leading to poor results as far as accuracy is concerned. It was argued that the deviations in the practice of the technique have resulted in the reduced accuracies (for both failure to include and failure to exclude) that are noted in several recent studies. This paper aims to present the results from recent research to highlight the advancement of skull-photo/cranio-facial superimposition, and to discuss some of the issues raised regarding deviations from original techniques. The evolving methodology of CFS is clarified in context with the advancement of technology, forensic science and specifically within the field of forensic anthropology. Developments in the skull-photo/cranio-facial superimposition techniques have largely focused on testing reliability and accuracy objectively. Techniques now being employed by forensic anthropologists must conform to rigorous scientific testing and methodologies. Skull-photo/cranio-facial superimposition is constantly undergoing accuracy and repeatability testing which is in line with the principles of the scientific method and additionally allows for advancement in the field. Much of the research has indicated that CFS is useful in exclusion which is consistent with the concept of Popperian falsifiability - a hypothesis and experimental design which is falsifiable. As the hypothesis is disproved or falsified, another evolves to replace it and explain the new observations. Current and future studies employing different methods to test the accuracy and reliability of skull-photo/cranio-facial superimposition will enable researchers to establish the contribution the technique can have for identification purposes. PMID:26970657

  6. Growth, children, and fractures.

    PubMed

    Jones, Graeme

    2004-09-01

    Fractures in childhood have long been considered an unavoidable consequence of growth. Studies in recent years have documented the epidemiology of these very common fractures and have also documented considerable variation by fracture type and from country to country. There have also been a number of studies aimed at identifying risk factors particularly for the most common distal forearm fracture. These studies have consistently associated bone mineral density with these fractures. Other possible risk factors include obesity, physical inactivity, sports, cola beverages, calcium intake, risk taking, and coordination. While prospective studies are required to confirm these risk factors, accumulating evidence now suggests that a substantial proportion of fractures in children are preventable. PMID:16036086

  7. Conceptual transitions in methods of skull-photo superimposition that impact the reliability of identification: a review.

    PubMed

    Jayaprakash, Paul T

    2015-01-01

    Establishing identification during skull-photo superimposition relies on correlating the salient morphological features of an unidentified skull with those of a face-image of a suspected dead individual using image overlay processes. Technical progression in the process of overlay has included the incorporation of video cameras, image-mixing devices and software that enables real-time vision-mixing. Conceptual transitions occur in the superimposition methods that involve 'life-size' images, that achieve orientation of the skull to the posture of the face in the photograph and that assess the extent of match. A recent report on the reliability of identification using the superimposition method adopted the currently prevalent methods and suggested an increased rate of failures when skulls were compared with related and unrelated face images. The reported reduction in the reliability of the superimposition method prompted a review of the transition in the concepts that are involved in skull-photo superimposition. The prevalent popular methods for visualizing the superimposed images at less than 'life-size', overlaying skull-face images by relying on the cranial and facial landmarks in the frontal plane when orienting the skull for matching and evaluating the match on a morphological basis by relying on mix-mode alone are the major departures in the methodology that may have reduced the identification reliability. The need to reassess the reliability of the method that incorporates the concepts which have been considered appropriate by the practitioners is stressed. PMID:25498986

  8. Panorama of Reconstruction of Skull Base Defects: From Traditional Open to Endonasal Endoscopic Approaches, from Free Grafts to Microvascular Flaps

    PubMed Central

    Reyes, Camilo; Mason, Eric; Solares, C. Arturo

    2014-01-01

    Introduction A substantial body of literature has been devoted to the distinct characteristics and surgical options to repair the skull base. However, the skull base is an anatomically challenging location that requires a three-dimensional reconstruction approach. Furthermore, advances in endoscopic skull base surgery encompass a wide range of surgical pathology, from benign tumors to sinonasal cancer. This has resulted in the creation of wide defects that yield a new challenge in skull base reconstruction. Progress in technology and imaging has made this approach an internationally accepted method to repair these defects. Objectives Discuss historical developments and flaps available for skull base reconstruction. Data Synthesis Free grafts in skull base reconstruction are a viable option in small defects and low-flow leaks. Vascularized flaps pose a distinct advantage in large defects and high-flow leaks. When open techniques are used, free flap reconstruction techniques are often necessary to repair large entry wound defects. Conclusions Reconstruction of skull base defects requires a thorough knowledge of surgical anatomy, disease, and patient risk factors associated with high-flow cerebrospinal fluid leaks. Various reconstruction techniques are available, from free tissue grafting to vascularized flaps. Possible complications that can befall after these procedures need to be considered. Although endonasal techniques are being used with increasing frequency, open techniques are still necessary in selected cases. PMID:25992142

  9. Current Challenges in Pain Management in Hip Fracture Patients.

    PubMed

    Sanzone, Anthony G

    2016-05-01

    The high incidence of hip fracture, together with considerable associated morbidity, mortality, and cost of care, makes this injury a major clinical challenge. Of particular importance is the pain associated with hip fracture, which can have potentially severe consequences and may lead to delayed recovery. The prevailing opioid-dependent model of analgesia, however, presents multiple drawbacks and risks that can compromise outcomes in the hip fracture population. The pain management process has essential preoperative, intraoperative, and postoperative components, yet data on the comparative effectiveness of different pain management interventions in patients undergoing surgery for hip fracture are not clear cut. A Cochrane database review that included 83 different pain management studies indicated that there are not enough well-designed studies to show unequivocally which pain management approaches work well after hip fracture surgery. Yet a growing body of data on certain interventions, such as nerve blocks and multimodal analgesia, supports consideration of these options. PMID:27101319

  10. Fracture tooth fragment reattachment

    PubMed Central

    Maitin, Nitin; Maitin, Shipra Nangalia; Rastogi, Khushboo; Bhushan, Rajarshi

    2013-01-01

    Coronal fractures of the anterior teeth are a common form of dental trauma and its sequelae may impair the establishment and accomplishment of an adequate treatment plan. Among the various treatment options, reattachment of a crown fragment is a conservative treatment that should be considered for crown fractures of anterior teeth. This clinical case reports the management of two coronal tooth fracture cases that were successfully treated using tooth fragment reattachment using glass-fibre-reinforced composite post. PMID:23853012

  11. Non-human primate skull effects on the cavitation detection threshold of FUS-induced blood-brain barrier opening

    NASA Astrophysics Data System (ADS)

    Wu, Shih-Ying; Tung, Yao-Sheng; Marquet, Fabrice; Chen, Cherry C.; Konofagou, Elisa E.

    2012-11-01

    Microbubble (MB)-assisted focused ultrasound is a promising technique for delivering drugs to the brain by noninvasively and transiently opening the blood-brain barrier (BBB), and monitoring BBB opening using passive cavitation detection (PCD) is critical in detecting its occurrence, extent as well as assessing its mechanism. One of the main obstacles in achieving those objectives in large animals is the transcranial attenuation. To study the effects, the cavitation response through the in-vitro non-human primate (NHP) skull was investigated. In-house manufactured lipid-shelled MB (medium diameter: 4-5 um) were injected into a 4-mm channel of a phantom below a degassed monkey skull. A hydrophone confocally aligned with the FUS transducer served as PCD during sonication (frequency: 0.50 MHz, peak rarefactional pressures: 0.05-0.60 MPa, pulse length: 100 cycles, PRF: 10 Hz, duration: 2 s) for four cases: water without skull, water with skull, MB without skull and MB with skull. A 5.1-MHz linear-array transducer was also used to monitor the MB disruption. The frequency spectra, spectrograms, stable cavitation dose (SCD) and inertial cavitation dose (ICD) were quantified. Results showed that the onset of stable cavitation and inertial cavitation in the experiments occurred at 50 kPa, and was detectable throught the NHP skull since the both the detection thresholds for stable cavitation and inertial cavitation remained unchanged compared to the non-skull case, and the SCD and ICD acquired transcranially may not adequately represent the true extent of stable and inertial cavitation due to the skull attenuation.

  12. Pathological fractures in children

    PubMed Central

    De Mattos, C. B. R.; Binitie, O.; Dormans, J. P.

    2012-01-01

    Pathological fractures in children can occur as a result of a variety of conditions, ranging from metabolic diseases and infection to tumours. Fractures through benign and malignant bone tumours should be recognised and managed appropriately by the treating orthopaedic surgeon. The most common benign bone tumours that cause pathological fractures in children are unicameral bone cysts, aneurysmal bone cysts, non-ossifying fibromas and fibrous dysplasia. Although pathological fractures through a primary bone malignancy are rare, these should be recognised quickly in order to achieve better outcomes. A thorough history, physical examination and review of plain radiographs are crucial to determine the cause and guide treatment. In most benign cases the fracture will heal and the lesion can be addressed at the time of the fracture, or after the fracture is healed. A step-wise and multidisciplinary approach is necessary in caring for paediatric patients with malignancies. Pathological fractures do not have to be treated by amputation; these fractures can heal and limb salvage can be performed when indicated. PMID:23610658

  13. Fracture detection logging tool

    DOEpatents

    Benzing, William M.

    1992-06-09

    A method and apparatus by which fractured rock formations are identified and their orientation may be determined includes two orthogonal motion sensors which are used in conjunction with a downhole orbital vibrator. The downhole vibrator includes a device for orienting the sensors. The output of the sensors is displayed as a lissajou figure. The shape of the figure changes when a subsurface fracture is encountered in the borehole. The apparatus and method identifies fractures rock formations and enables the azimuthal orientation of the fractures to be determined.

  14. Capitellar and Trochlear Fractures.

    PubMed

    Carroll, Michael J; Athwal, George S; King, Graham J W; Faber, Kenneth J

    2015-11-01

    Fractures of the capitellum and trochlea account for a small proportion of elbow trauma. Clinicians need to be vigilant in their assessment as they are commonly associated with other injuries about the elbow. To optimize outcomes, the goals of management include a stable, anatomic reduction and early range of motion. Closed reduction of noncomminuted fractures may be successful but requires close follow-up. Open reduction and internal fixation is the preferred management of displaced capitellum-trochlear fractures. Elbow stiffness is the most commonly reported complication in operatively treated fractures. Arthroscopic-assisted reduction and internal fixation and arthroplasty are evolving management options. PMID:26498550

  15. Pterygoid Plate Fractures: Not Limited to Le Fort Fractures.

    PubMed

    Garg, Ravi K; Alsheik, Nila H; Afifi, Ahmed M; Gentry, Lindell R

    2015-09-01

    Pterygoid plate fractures are often described in the setting of Le Fort fractures. The goal of this study was to define other craniofacial fracture patterns causing injury to the pterygoid plates. A retrospective review of computed tomography (CT) scans obtained on craniofacial trauma patients over a 5-year period revealed 209 patients with pterygoid plate fractures. Pterygoid plate fractures in 78 patients (37.3%) were unrelated to Le Fort fractures. Common causes included sphenotemporal buttress fractures in 26 patients (33.3%), temporal bone fractures in 18 patients (23.1%), zygomaticomaxillary complex fractures in 17 patients (21.8%), and displaced mandible fractures in 14 patients (17.9%). These findings indicate that approximately one third of pterygoid plate fractures do not result from Le Fort pattern injuries and that the craniofacial surgeon should have a broad differential for causes of pterygoid plate fractures when reviewing trauma imaging. PMID:26147022

  16. Maximising functional recovery following hip fracture in frail seniors.

    PubMed

    Beaupre, Lauren A; Binder, Ellen F; Cameron, Ian D; Jones, C Allyson; Orwig, Denise; Sherrington, Cathie; Magaziner, Jay

    2013-12-01

    This review discusses factors affecting recovery following hip fracture in frail older people as well as interventions associated with improved functional recovery. Prefracture function, cognitive status, co-morbidities, depression, nutrition and social support impact recovery and may interact to affect post-fracture outcome. There is mounting evidence that exercise is beneficial following hip fracture with higher-intensity/duration programmes showing more promising outcomes. Pharmacologic management for osteoporosis has benefits in preventing further fractures, and interest is growing in pharmacologic treatments for post-fracture loss of muscle mass and strength. A growing body of evidence suggests that sub-populations - those with cognitive impairment, residing in nursing homes or males - also benefit from rehabilitation after hip fracture. Optimal post-fracture care may entail the use of multiple interventions; however, more work is needed to determine optimal exercise components, duration and intensity as well as exploring the impact of multimodal interventions that combine exercise, pharmacology, nutrition and other interventions. PMID:24836335

  17. Growing skin: Tissue expansion in pediatric forehead reconstruction

    PubMed Central

    Zollner, Alexander M.; Buganza Tepole, Adrian; Gosain, Arun K.; Kuhl, Ellen

    2011-01-01

    Tissue expansion is a common surgical procedure to grow extra skin through controlled mechanical over-stretch. It creates skin that matches the color, texture, and thickness of the surrounding tissue, while minimizing scars and risk of rejection. Despite intense research in tissue expansion and skin growth, there is a clear knowledge gap between heuristic observation and mechanistic understanding of the key phenomena that drive the growth process. Here, we show that a continuum mechanics approach, embedded in a custom-designed finite element model, informed by medical imaging, provides valuable insight into the biomechanics of skin growth. In particular, we model skin growth using the concept of an incompatible growth configuration. We characterize its evolution in time using a second-order growth tensor parameterized in terms of a scalar-valued internal variable, the in-plane area growth. When stretched beyond the physiological level, new skin is created, and the in-plane area growth increases. For the first time, we simulate tissue expansion on a patient-specific geometric model, and predict stress, strain, and area gain at three expanded locations in a pediatric skull: in the scalp, in the forehead, and in the cheek. Our results may help the surgeon to prevent tissue over-stretch and make informed decisions about expander geometry, size, placement, and inflation. We anticipate our study to open new avenues in reconstructive surgery, and enhance treatment for patients with birth defects, burn injuries, or breast tumor removal. PMID:22052000

  18. Scene segmentation through region growing

    NASA Technical Reports Server (NTRS)

    Latty, R. S.

    1984-01-01

    A computer algorithm to segment Landsat Thematic Mapper (TM) images into areas representing surface features is described. The algorithm is based on a region growing approach and uses edge elements and edge element orientation to define the limits of the surface features. Adjacent regions which are not separated by edges are linked to form larger regions. Some of the advantages of scene segmentation over conventional TM image extraction algorithms are discussed, including surface feature analysis on a pixel-by-pixel basis, and faster identification of the pixels in each region. A detailed flow diagram of region growing algorithm is provided.

  19. Prevalence and Nature of Dentoalveolar Injuries Among Patients with Maxillofacial Fractures

    PubMed Central

    Mulherin, Brenda L.; Snyder, Christopher J.

    2014-01-01

    Structure Summary Objective Although not previously reported, experience suggests that dentoalveolar injury (DAI) is common among patients with maxillofacial (MF) fractures. The objective of this study was to evaluate and describe the prevalence and nature of DAIs in patients identified with MF fractures. Methods Medical records of 43 dogs and cats diagnosed with MF fractures between 2005–2012 were reviewed to identify patients with concurrent DAI. Medical records of patients with DAI were abstracted for the following information: signalment (including sex, age, and skull type), mechanism of MF trauma, location and number of MF fractures, DAI type and location and the number of DAI per patient. Statistical evaluation was performed to determine associations between signalment; mechanism of trauma; location and number of MF fractures; and the prevalence and nature of concurrent DAI. Results Dentoalveolar injuries are common among patients with MF trauma. Age and mechanism of trauma are significant predictors of the presence of DAI in patients with MF trauma. Conclusions and Clinical Relevance The findings of this study serve to encourage veterinarians to fully assess the oral cavity in patients with MF fractures as DAI are common and can be predicted by age and mechanism of trauma. PMID:23033815

  20. Growth by Optimization of Work (GROW): A new modeling tool that predicts fault growth through work minimization

    NASA Astrophysics Data System (ADS)

    McBeck, Jessica A.; Madden, Elizabeth H.; Cooke, Michele L.

    2016-03-01

    Growth by Optimization of Work (GROW) is a new modeling tool that automates fracture initiation, propagation, interaction, and linkage. GROW predicts fracture growth by finding the propagation path and fracture geometry that optimizes the global external work of the system. This implementation of work optimization is able to simulate more complex paths of fracture growth than energy release rate methods. In addition, whereas a Coulomb stress analysis determines two conjugate planes of potential failure, GROW identifies a single failure surface for each increment of growth. GROW also eliminates ambiguity in determining whether shear or tensile failure will occur at a fracture tip by assessing both modes of failure by the same propagation criterion. Here we describe the underlying algorithm of the program and present GROW models of two propagating faults separated by a releasing step. The discretization error of these models demonstrates that GROW can predict fault propagation paths within the numerical uncertainty produced by discretization. Model element size moderately influences the propagation paths, however, the final fault geometry remains similar between models with significantly different element sizes. The propagation power of the fault system, calculated from the change in work due to fault propagation, indicates when model faults interact through both soft- and hard-linkage.

  1. Topographic analysis of the skull vibration-induced nystagmus test with piezoelectric accelerometers and force sensors.

    PubMed

    Dumas, Georges; Lion, Alexis; Perrin, Philippe; Ouedraogo, Evariste; Schmerber, Sébastien

    2016-03-23

    Vibration-induced nystagmus is elicited by skull or posterior cervical muscle stimulations in patients with vestibular diseases. Skull vibrations delivered by the skull vibration-induced nystagmus test are known to stimulate the inner ear structures directly. This study aimed to measure the vibration transfer at different cranium locations and posterior cervical regions to contribute toward stimulus topographic optimization (experiment 1) and to determine the force applied on the skull with a hand-held vibrator to study the test reproducibility and provide recommendations for good clinical practices (experiment 2). In experiment 1, a 100 Hz hand-held vibrator was applied on the skull (vertex, mastoids) and posterior cervical muscles in 11 healthy participants. Vibration transfer was measured by piezoelectric sensors. In experiment 2, the vibrator was applied 30 times by two experimenters with dominant and nondominant hands on a mannequin equipped to measure the force. Experiment 1 showed that after unilateral mastoid vibratory stimulation, the signal transfer was higher when recorded on the contralateral mastoid than on the vertex or posterior cervical muscles (P<0.001). No difference was observed between the different vibratory locations when vibration transfer was measured on vertex and posterior cervical muscles. Experiment 2 showed that the force applied to the mannequin varied according to the experimenters and the handedness, higher forces being observed with the most experienced experimenter and with the dominant hand (10.3±1.0 and 7.8±2.9 N, respectively). The variation ranged from 9.8 to 29.4% within the same experimenter. Bone transcranial vibration transfer is more efficient from one mastoid to the other mastoid than other anatomical sites. The mastoid is therefore the optimal site for skull vibration-induced nystagmus test in patients with unilateral vestibular lesions and enables a stronger stimulation of the healthy side. In clinical practice

  2. Growing Ideas, 1990-1993.

    ERIC Educational Resources Information Center

    Pranis, Eve, Ed.

    1993-01-01

    This series of journals includes volumes 1-4 of "Growing Ideas," a journal of garden-based learning. Each issue provides instructional ideas, horticultural information and a forum for exchange among teachers using classroom gardening to stimulate learning. Ideas in each issue are separated into three sections. The "Green Tips" section presents…

  3. Exploring Classroom Hydroponics. Growing Ideas.

    ERIC Educational Resources Information Center

    National Gardening Association, Burlington, VT.

    Growing Ideas, the National Gardening Association's series for elementary, middle, and junior high school educators, helps teachers engage students in using plants and gardens as contexts for developing a deeper, richer understanding of the world around them. This volume's focus is on hydroponics. It presents basic hydroponics information along…

  4. Growing an Emerging Research University

    ERIC Educational Resources Information Center

    Birx, Donald L.; Anderson-Fletcher, Elizabeth; Whitney, Elizabeth

    2013-01-01

    The emerging research college or university is one of the most formidable resources a region has to reinvent and grow its economy. This paper is the first of two that outlines a process of building research universities that enhance regional technology development and facilitate flexible networks of collaboration and resource sharing. Although the…

  5. Growing Patterns: Seeing beyond Counting

    ERIC Educational Resources Information Center

    Markworth, Kimberly A.

    2012-01-01

    Over the past two decades, mathematical patterns have been acknowledged as important early components of children's development of algebraic reasoning (NCTM 2000). In particular, growing patterns have attracted significant attention as a context that helps students develop an understanding of functional relationships (Lee and Freiman 2006; Moss et…

  6. Consequences of Growing Up Poor.

    ERIC Educational Resources Information Center

    Duncan, Greg J., Ed.; Brooks-Gunn, Jeanne, Ed.

    The consequences and correlates of growing up poor as well as the mechanisms through which poverty influences children are explored. This book is organized with a primary focus on research findings and a secondary concern with policy implications. The chapters are: (1) "Poor Families, Poor Outcomes: The Well-Being of Children and Youth" (Jeanne…

  7. Growing Your Own: Minority Teachers

    ERIC Educational Resources Information Center

    Singh, Delar K.; Stoloff, David L.

    2007-01-01

    In the USA, the number of school age children who represent minority backgrounds is rapidly growing. However, despite several efforts, the teaching force remains primarily White. The purpose of this paper is to describe a residential future teachers program in Connecticut which recruits minority rising juniors and seniors from high schools across…

  8. How Does Your Garlic Grow?

    ERIC Educational Resources Information Center

    Shimabukuro, Mary A.; Fearing, Vickie

    1993-01-01

    Garlic is an ideal plant for the elementary classroom. It grows rapidly in water without aeration for several weeks and remains relatively free of microbial contamination. Simple experiments with garlic purchased at grocery stores can illustrate various aspects of plant growth. (PR)

  9. Colleges' Earmarks Grow, Amid Criticism

    ERIC Educational Resources Information Center

    Brainard, Jeffrey; Hermes, J. J.

    2008-01-01

    A record-breaking number of Congressional pork-barrel projects this year has loaded college and university plates with more earmarks than ever before, despite growing worries that the noncompetitive grants undermine the American scientific enterprise, and in spite of promises by some lawmakers to cut back. An analysis by "The Chronicle" shows that…

  10. How the pilidium larva grows

    PubMed Central

    2014-01-01

    Background For animal cells, ciliation and mitosis appear to be mutually exclusive. While uniciliated cells can resorb their cilium to undergo mitosis, multiciliated cells apparently can never divide again. Nevertheless, many multiciliated epithelia in animals must grow or undergo renewal. The larval epidermis in a number of marine invertebrate larvae, such as those of annelids, mollusks and nemerteans, consists wholly or in part of multiciliated epithelial cells, generally organized into a swimming and feeding apparatus. Many of these larvae must grow substantially to reach metamorphosis. Do individual epithelial cells simply expand to accommodate an increase in body size, or are there dividing cells amongst them? If some cells divide, where are they located? Results We show that the nemertean pilidium larva, which is almost entirely composed of multiciliated cells, retains pockets of proliferative cells in certain regions of the body. Most of these are found near the larval ciliated band in the recesses between the larval lobes and lappets, which we refer to as axils. Cells in the axils contribute both to the growing larval body and to the imaginal discs that form the juvenile worm inside the pilidium. Conclusions Our findings not only explain how the almost-entirely multiciliated pilidium can grow, but also demonstrate direct coupling of larval and juvenile growth in a maximally-indirect life history. PMID:24690541

  11. Growing Crystals on the Ceiling.

    ERIC Educational Resources Information Center

    Christman, Robert A.

    1980-01-01

    Described is a method of studying growing crystals in a classroom utilizing a carrousel projector standing vertically. A saturated salt solution is placed on a slide on the lens of the projector and the heat from the projector causes the water to evaporate and salt to crystalize. (Author/DS)

  12. Organization of growing random networks

    SciTech Connect

    Krapivsky, P. L.; Redner, S.

    2001-06-01

    The organizational development of growing random networks is investigated. These growing networks are built by adding nodes successively, and linking each to an earlier node of degree k with an attachment probability A{sub k}. When A{sub k} grows more slowly than linearly with k, the number of nodes with k links, N{sub k}(t), decays faster than a power law in k, while for A{sub k} growing faster than linearly in k, a single node emerges which connects to nearly all other nodes. When A{sub k} is asymptotically linear, N{sub k}(t){similar_to}tk{sup {minus}{nu}}, with {nu} dependent on details of the attachment probability, but in the range 2{lt}{nu}{lt}{infinity}. The combined age and degree distribution of nodes shows that old nodes typically have a large degree. There is also a significant correlation in the degrees of neighboring nodes, so that nodes of similar degree are more likely to be connected. The size distributions of the in and out components of the network with respect to a given node{emdash}namely, its {open_quotes}descendants{close_quotes} and {open_quotes}ancestors{close_quotes}{emdash}are also determined. The in component exhibits a robust s{sup {minus}2} power-law tail, where s is the component size. The out component has a typical size of order lnt, and it provides basic insights into the genealogy of the network.

  13. Extreme Mechanics of Growing Matter

    NASA Astrophysics Data System (ADS)

    Kuhl, Ellen

    2013-03-01

    Growth is a distinguishing feature of all living things. Unlike standard materials, living matter can autonomously respond to alterations in its environment. As a result of a continuous ultrastructural turnover and renewal of cells and extracellular matrix, living matter can undergo extreme changes in composition, size, and shape within the order of months, weeks, or days. While hard matter typically adapts by increasing its density to grow strong, soft matter adapts by increasing its volume to grow large. Here we provide a state-of-the-art review of growing matter, and compare existing mathematical models for growth and remodeling of living systems. Applications are plentiful ranging from plant growth to tumor growth, from asthma in the lungs to restenosis in the vasculature, from plastic to reconstructive surgery, and from skeletal muscle adaptation to heart failure. Using these examples, we discuss current challenges and potential future directions. We hope to initiate critical discussions around the biophysical modeling of growing matter as a powerful tool to better understand biological systems in health and disease. This research has been supported by the NSF CAREER award CMMI 0952021.

  14. TIBIAL SHAFT FRACTURES

    PubMed Central

    Kojima, Kodi Edson; Ferreira, Ramon Venzon

    2015-01-01

    The long-bone fractures occur most frequently in the tibial shaft. Adequate treatment of such fractures avoids consolidation failure, skewed consolidation and reoperation. To classify these fractures, the AO/OTA classification method is still used, but it is worthwhile getting to know the Ellis classification method, which also includes assessment of soft-tissue injuries. There is often an association with compartmental syndrome, and early diagnosis can be achieved through evaluating clinical parameters and constant clinical monitoring. Once the diagnosis has been made, fasciotomy should be performed. It is always difficult to assess consolidation, but the RUST method may help in this. Radiography is assessed in two projections, and points are scored for the presence of the fracture line and a visible bone callus. Today, the dogma of six hours for cleaning the exposed fracture is under discussion. It is considered that an early start to intravenous antibiotic therapy and the lesion severity are very important. The question of early or late closure of the lesion in an exposed fracture has gone through several phases: sometimes early closure has been indicated and sometimes late closure. Currently, whenever possible, early closure of the lesion is recommended, since this diminishes the risk of infection. Milling of the canal when the intramedullary nail is introduced is still a controversial subject. Despite strong personal positions in favor of milling, studies have shown that there may be some advantage in relation to closed fractures, but not in exposed fractures. PMID:27026999

  15. Rib fracture - aftercare

    MedlinePlus

    A rib fracture is a crack or break in one or more of your rib bones. Your ribs are the round, flat bones in your chest ... A rib fracture can be very painful because your ribs move when you breathe, cough, and move your upper ...

  16. Origin of Permeability and Structure of Flows in Fractured Media

    NASA Astrophysics Data System (ADS)

    De Dreuzy, J.; Darcel, C.; Davy, P.; Erhel, J.; Le Goc, R.; Maillot, J.; Meheust, Y.; Pichot, G.; Poirriez, B.

    2013-12-01

    After more than three decades of research, flows in fractured media have been shown to result from multi-scale geological structures. Flows result non-exclusively from the damage zone of the large faults, from the percolation within denser networks of smaller fractures, from the aperture heterogeneity within the fracture planes and from some remaining permeability within the matrix. While the effect of each of these causes has been studied independently, global assessments of the main determinisms is still needed. We propose a general approach to determine the geological structures responsible for flows, their permeability and their organization based on field data and numerical modeling [de Dreuzy et al., 2012b]. Multi-scale synthetic networks are reconstructed from field data and simplified mechanical modeling [Davy et al., 2010]. High-performance numerical methods are developed to comply with the specificities of the geometry and physical properties of the fractured media [Pichot et al., 2010; Pichot et al., 2012]. And, based on a large Monte-Carlo sampling, we determine the key determinisms of fractured permeability and flows (Figure). We illustrate our approach on the respective influence of fracture apertures and fracture correlation patterns at large scale. We show the potential role of fracture intersections, so far overlooked between the fracture and the network scales. We also demonstrate how fracture correlations reduce the bulk fracture permeability. Using this analysis, we highlight the need for more specific in-situ characterization of fracture flow structures. Fracture modeling and characterization are necessary to meet the new requirements of a growing number of applications where fractures appear both as potential advantages to enhance permeability and drawbacks for safety, e.g. in energy storage, stimulated geothermal energy and non-conventional gas productions. References Davy, P., et al. (2010), A likely universal model of fracture scaling and

  17. Dynamic fracture mechanics

    NASA Technical Reports Server (NTRS)

    Kobayashi, A. S.; Ramulu, M.

    1985-01-01

    Dynamic fracture and crack propagation concepts for ductile materials are reviewed. The equations for calculating dynamic stress integrity and the dynamic energy release rate in order to study dynamic crack propagation are provided. The stress intensity factor versus crack velocity relation is investigated. The uses of optical experimental techniques and finite element methods for fracture analyses are described. The fracture criteria for a rapidly propagating crack under mixed mode conditions are discussed; crack extension and fracture criteria under combined tension and shear loading are based on maximum circumferential stress or energy criteria such as strain energy density. The development and use of a Dugdale model and finite element models to represent crack and fracture dynamics are examined.

  18. Transphyseal Distal Humerus Fracture.

    PubMed

    Abzug, Joshua; Ho, Christine Ann; Ritzman, Todd F; Brighton, Brian

    2016-01-01

    Transphyseal distal humerus fractures typically occur in children younger than 3 years secondary to birth trauma, nonaccidental trauma, or a fall from a small height. Prompt and accurate diagnosis of a transphyseal distal humerus fracture is crucial for a successful outcome. Recognizing that the forearm is not aligned with the humerus on plain radiographs may aid in the diagnosis of a transphyseal distal humerus fracture. Surgical management is most commonly performed with the aid of an arthrogram. Closed reduction and percutaneous pinning techniques similar to those used for supracondylar humerus fractures are employed. Cubitus varus caused by a malunion, osteonecrosis of the medial condyle, or growth arrest is the most common complication encountered in the treatment of transphyseal distal humerus fractures. A corrective lateral closing wedge osteotomy can be performed to restore a nearly normal carrying angle. PMID:27049206

  19. Apparent capitellar fractures.

    PubMed

    Ring, David

    2007-11-01

    Isolated capitellar fractures are rare but are identified as such, even when they are more complex, because the displaced capitellar fracture is usually the most obvious and identifiable radiographic finding and because teaching has traditionally underemphasized the involvement of the trochlea in such fractures. The author prefers the term 'apparent capitellar fractures' and draws on his experience to explain why he favors three-dimensional CT for depicting fracture detail. This article discusses treatment options, emphasizing open reduction and internal fixation to restore the native elbow. Operative techniques, including extensile lateral exposure and olecranon osteotomy; fixation techniques; and elbow arthroplasty, are described. Complications, such as ulnar neuropathy and infection, are also covered. PMID:18054674

  20. Counting 241Am in the BfS human skull phantom on contact-evaluation in the human monitoring laboratory.

    PubMed

    Li, Chunsheng; Hauck, Barry; Capello, Kevin; Nogueira, Pedro; Lopez, Maria A; Kramer, Gary H

    2015-03-01

    Skull counting can be used to assess the activity of radionuclides internally deposited in the bone. The Human Monitoring Laboratory (HML) at Health Canada conducted the measurement of 241Am in the BfS (Bundesamt für Strahlenschuts) skull phantom on contact with the skull for various positions. By placing the detector in contact, the HML can improve the counting efficiency by over 20% compared to placing the detector 1 cm above the surface of the skull. Among all the positions tested, the forehead position is the preferred counting geometry due to the design of HML's counting facility and the comfort it would provide to the individual being counted, although this counting position did not offer the highest counting efficiency for the gamma rays (either the 59.5 keV or the 26.3 keV) emitted by 241Am. PMID:25627952