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This study aimed to control radiation doses when using a portable supine dental panoramic radiography system by measured the scattered doses. The study used LPX7007 (Asahi Roentgen) for the panoramic radiography system. The subjects comprised a cylinder phantom (QualitA) and a RANDO Phantom (Alderson). The semiconductor dosimeter was an X2 survey sensor (RaySafe). The phantom was set at a height of 1 m from the floor, and the sensor was set at 1 m from the floor at the genital level and 1.5 m at the lens level. Measurements were taken at 30°intervals clockwise from 0°at distances of 0.5 m and 1 m in radius around the phantom. The occupational exposure range was defined as 0 ± 30° and the public exposure range was defined as the occupational exposure range and 30° to 150° and 210° to 330° as the public exposure range. The highest doses were observed in the 120° and 240° directions, and the lowest in 0° ± 30° range. The lowest limit number of images taken in the occupational exposure range was 130 images at a distance of 0.5 m, 452 images at 1 m at the lens level for the cylinder phantom, and 320 images at 0.5 m and 1098 images at 1 m for the RANDO Phantom. In the public exposure range at the genital level, there was one image at 0.5 m and six images at 1 m for the cylinder phantom, and two images at 0.5 m and eight images at 1 m for the RANDO Phantom. We found that radiation exposure can be reduced by keeping a distance from the subject, avoiding working at 120° and 240° and staying within 0° ± 30° behind the panoramic radiography system. [ABSTRACT FROM AUTHOR]

Background The internal maxillary artery (IMA) is a reliable donor for extracranial–intracranial high-flow bypasses. However, previously described landmarks and techniques to harvest the IMA are complex and confusing and require extensive bone drilling, carrying significant neurovascular risk. The objective of our study was to describe a minimally invasive technique for exposing the IMA and to assess the feasibility of using the IMA as a donor for anterior-circulation recipient vessels using 2 different local interposition vessels. Methods Via a minimally invasive technique, the IMA was harvested in 10 cadaveric specimens and a pterional craniotomy was performed. Two interposition grafts—the superficial temporal artery (STA) and middle temporal artery—were evaluated individually. Transsylvian exposure of the second segment of middle cerebral artery (M2), the supraclinoid internal carotid artery, and the proximal postcommunicating anterior cerebral artery segment was completed. Relevant vessel calibers and graft lengths were measured for each bypass model. Results The mean caliber of the IMA was 2.7 ± 0.5 mm. Of all 3 recipients, the shortest graft length was seen in the IMA-STA-M2 bypass, measuring 42.0 ± 8.4 mm. There was a good caliber match between the M2 (2.4 ± 0.4 mm) and STA (2.3 ± 0.4 mm) at the anastomotic site. The harvested middle temporal artery was sufficient in length in only 30% cases, with a mean distal caliber of 2.0 ± 0.7 mm. Conclusions This study confirmed the technical feasibility of IMA as a donor for an extracranial–intracranial bypass to the second segment of the anterior cerebral artery, M2, and the supraclinoid internal carotid artery. However, IMA-STA-M2 was observed to be the most suitable bypass model. Highlights • We tested the feasibility of IMA as a viable high-flow donor for an EC–IC bypass to the anterior circulation. • Interposition grafts evaluated for the study include superficial temporal artery and middle temporal artery. • Use of minimally invasive technique for IMA harvest as a donor. [ABSTRACT FROM AUTHOR]

Previously, only three pachycephalosaur specimens have been reported from the Nemegt Formation, two of which are holotypes ( Homalocephale calathocercos and Prenocephale prenes ) and all of which were collected from the classic Nemegt locality. Here, we describe several new cranial specimens from this formation, but which originate from Bügiin Tsav, Guriliin Tsav, and Tsagaan Khushuu localities. The specimens consist of an incomplete frontoparietal dome that is slightly smaller than the holotype of P . prenes , and two specimens that are larger than the holotype –a second incomplete frontoparietal and a complete squamosal with ornamentation. All specimens are referable to P . prenes or cf. Prenocephale . Cranial histology is investigated in an Asian pachycephalosaur for the first time on the basis of these new specimens. The specimens increase the ontogenetic representation for Prenocephale , and show that the squamosal ornamentation pattern is consistent across the known size range. These specimens expand the geographic range of pachycephalosaurs in the Nemegt Formation, and provide new ontogenetic data for P . prenes that reinforces the taxonomic distinction between it and Homalocephale . [ABSTRACT FROM AUTHOR]

For patients with occipital malformation, it is difficult to obtain reliable stability using three screws on the midline. A new aliform occipitocervical internal fixation system was designed. The occiput was fixed with 3, 7, or 11 screws, and a three-dimensional finite element model of the system was established. A compressive preload of 40 N combined with a pure moment of 1.5 Nm was applied to simulate normal flexion, extension, lateral bending, and axial rotation. The stress distribution across the screws on the occiput and the occipital displacement produced by the newly developed system were compared with those produced by the DePuy SUMMIT system. Compared with the SUMMIT system (control group), in the new system, the maximum stress on the occiputs fixed with 3 screws (group A) and 7 screws (group B) increased by 16.5% and 15.0%, respectively. In contrast, the maximum stress on the occiput fixed with 11 screws (group C) decreased by 15.6%. In addition, the maximum occipital displacements under extension decreased by 10.0%, 11.4%, and 11.8% in the A, B, and, C groups, respectively. Our results indicate that both group A and the control group exhibited sufficient strength and instant stability; however, group C exhibited the highest stability and the lowest maximum von Mises stress. [ABSTRACT FROM AUTHOR]

Brachycephalic airway syndrome in dogs is typified by a variety of anatomical abnormalities causing a diverse spectrum of clinical signs of varying intensity. This variability makes the assessment of the surgical outcome after upper airway surgery difficult. Using a structured questionnaire, the present study investigated the dog owner-perceived severity and frequency of a broad spectrum of welfare-relevant impairments 2 weeks before and 6 months after brachycephalic dogs underwent a recently developed multi-level upper airway surgery. All dogs underwent surgical treatment of stenotic nares (ala-vestibuloplasty), the nasal cavity (laser-assisted turbinectomy, LATE), the pharynx (palatoplasty and tonsillotomy), and if indicated, laryngeal surgery (laser-assisted ablation of everted ventricles and partial cuneiformectomy). Owners of brachycephalic dogs ( n  = 102) referred for upper airway surgery were eligible to participate. Questionnaire data from owners of 37 Pugs and 25 French bulldogs were evaluated. In all dogs, the clinical signs associated with brachycephaly improved markedly after surgery. Most encouraging was the striking reduction in life-threatening events by 90% (choking fits decreased from 60% to 5% and collapse from 27% to 3%). The incidence of sleeping problems decreased from 55% to 3%, and the occurrence of breathing sounds declined by approximately 50%. There was a marked improvement in exercise tolerance and a modest improvement in heat tolerance. Dogs with severe brachycephaly benefitted substantially from multi-level surgery, and there were particular improvements in the incidences of severe impairment and life-threatening events. However, despite the marked improvement perceived by dog owners, these dogs remained clinically affected and continued to show welfare-relevant impairments caused by these hereditary disorders. [ABSTRACT FROM AUTHOR]

Identifying foot strike patterns in running is an important issue for sport clinicians, coaches and footwear industrials. Current methods allow the monitoring of either many steps in laboratory conditions or only a few steps in the field. Because measuring running biomechanics during actual practice is critical, our purpose is to validate a method aiming at identifying foot strike patterns during continuous field measurements. Based on heel and metatarsal accelerations, this method requires two uniaxial accelerometers. The time between heel and metatarsal acceleration peaks (THM) was compared to the foot strike angle in the sagittal plane (αfoot) obtained by 2D video analysis for various conditions of speed, slope, footwear, foot strike and state of fatigue. Acceleration and kinematic measurements were performed at 1000 Hz and 120 Hz, respectively, during 2-min treadmill running bouts. Significant correlations were observed between THM and αfoot for 14 out of 15 conditions. The overall correlation coefficient was r=0.916 (P< 0.0001, n = 288). The THM method is thus highly reliable for a wide range of speeds and slopes, and for all types of foot strike except for extreme forefoot strike during which the heel rarely or never strikes the ground, and for different footwears and states of fatigue. We proposed a classification based on THM: FFS < - 5.49 ms < MFS < 15.2 ms < RFS. With only a few precautions being necessary to ensure appropriate use of this method, it is reliable for distinguishing rearfoot and non-rearfoot strikers in situ. [ABSTRACT FROM AUTHOR]

Summary: Objectives: The purpose of the present study is to assess the effect of circus activity training on postural control of 5–6-year old children. Material and methods: Two groups of 5–6-year old children (12 practicing circus activities and 12 controls) voluntarily participated in this study. Children were asked to stand as still as possible on a force platform with eyes open and closed in a static posture and in two dynamic postures (in the sagittal or frontal plane). Postural control was assessed with centre of pressure excursions. Results: The results revealed that Circus group children have significant (P <.05) better postural control than controls. The significant (P <.05) effect of postural task difficulty on postural control was similar for both groups. Removal of vision decreases significantly (P <.05) the postural control of both groups similarly in all postures. This effect increased significantly (P <.05) when the difficulty of the postural task increased. Conclusion: Our results suggest that 2years of experience in circus activity training improves postural control of 5–6-year old children. Nevertheless, this effect could not nullify the common effect of removing vision on postural control of these children. [ABSTRACT FROM AUTHOR]

Abstract: Chromosome 2p15p16.1 microdeletion is an emerging syndrome recently described in patients with dysmorphic facial features, congenital microcephaly, mild to moderate developmental delay and neurodevelopmental abnormalities. Using clinical ultra-high resolution Affymetrix SNP 6.0 array we identified a de novo interstitial deletion on the short arm of chromosome 2, spanning approximately 2.5 Mb in the cytogenetic band position 2p15p16.1, in a female infant with characteristic features of 2p15p16.1 deletion syndrome including severe developmental delay, congenital microcephaly, intractable epilepsy, and renal anomalies, as well as a congenital choledochal cyst which has not been previously reported in other patients with this cytogenetic defect. We further redefined the previously reported critical region, supporting the presence of a newly recognized microdeletion syndrome involving haploinsufficiency of one or more genes deleted within at least a 1.1 Mb segment of the 2p15p16.1 region. [Copyright &y& Elsevier]

Abstract: The aim of this study was to compare the postoperative stability of the mandible after a bilateral lengthening procedure, either by bilateral sagittal split osteotomy (BSSO) or distraction osteogenesis (DO). All patients who underwent mandibular advancement surgery between March 2001 and June 2004 were evaluated. There were 17 patients in the BSSO group and 18 patients in the DO group. The decision to use intra-oral distraction or BSSO for mandibular advancement primarily depended on the choice of the patient and their parents. In both groups, standardized cephalometric radiographs were taken preoperatively, postoperatively (BSSO group) or directly post-distraction (DO group) and during the last study measurement in May 2008. Cephalometric analysis was performed using the following measurements: sella/nasion-mandibular point B and sella/nasion-mandibular plane. Point B was used to estimate relapse. This study showed no significant difference in relapse between the BSSO and the DO groups measured 46–95 months after advancement of the mandible (P >.05). It can be concluded from this study that there is no postoperative difference in the stability between BSSO and DO after mandibular advancement after 4 years. [Copyright &y& Elsevier]

Abstract: Fiducial markers (FMs) are commonly used as a correction technique for interfraction translations of the prostate. The aim of this investigation was to determine the magnitude of prostate rotations using 2 methods: FM coordinates and the anatomical border of the prostate and rectum. Daily computed tomography (CT) scans (n = 346) of 10 prostate cancer patients with 3 implanted FMs were acquired using the CT on rails. FM coordinates were used to determine rotation in the sagittal, transverse, and coronal planes, and CT contours of the prostate and rectum were used to determine rotation along the sagittal plane. An adaptive technique based on a subset of images (n = 6; planning and first 5 treatment CTs) to reduce systematic rotation errors in the sagittal plane was tested. The standard deviation (SD) of systematic rotation from FM coordinates was 7.6°, 7.7°, and 5.0° in the sagittal, transverse and coronal planes. The corresponding SD of random error was 10.2°, 15.8°, and 6.5°. Errors in the sagittal plane, determined from prostate and rectal contours, were 10.1° (systematic) and 7.7° (random). These results did not correlate with rotation computed from FM coordinates (r = −0.017; p = 0.753, n = 337). The systematic error could be reduced by 43% to 5.6° when the mean prostate position was estimated from 6 CT scans. Prostate rotation is a significant source of error that appears to be more accurately determined using the anatomical border of the prostate and rectum rather than FMs, thus highlighting the utility of CT image guidance. [Copyright &y& Elsevier]

Abstract: In a bilateral sagittal split osteotomy (BSSO) mechanical irritation of the inferior alveolar nerve (IAN) (e.g. by chiselling) should be avoided to prevent neural damage. A modification of the Obwegeser–Dal Pont operation technique was studied by splitting 100 pig mandibles ex vivo. An additional osteotomy at the caudal border of the mandible was used to facilitate the sagittal split by means of a locus of minor resistance. The chisel was inserted distal to the second molar and far away from the IAN. The mandible was split by torque. The modified technique reduced the required torque to split the mandible about 30% compared with the original technique (paired t-test, t(69)=−12.89; p <0.05). 75% of all mandibles split by the modified technique were classified as bad splits compared with 100% using the original technique using the same protocol without the additional osteotomy. [Copyright &y& Elsevier]

This retrospective study on cephalometric head films assessed the sagittal soft-issue changes in relation to the underlying hard tissue changes resulting from maxillary surgical correction in 26 Class III cases. Thirteen patients received additional mandibular surgery. The radiographs were taken immediately before surgery and from 3 to 16 months after surgery. Twenty-six cephalometric landmarks were identified, and 6 linear and 7 angular measurements on each radiograph were digitally recorded relative to X-Y coordinates traced on the radiographs. This system enabled the recording of horizontal and vertical changes of the hard and soft tissues. Proportional analyses between the cases that had maxillary advancement and those cases having additional mandibular surgery showed no significant differences. A strong correlation was found between the movement at the labrale superius and upper incisor tip and the response was recorded at a ratio of 0.55:1. Subnasale responded at a ratio of 0.52:1 and anterior nasal tip by 0.26:1 relative to upper incisor anterius. V–Y surgical lip closure decreased lip shortening as the maxilla is advanced but had little effect on forecasting horizontal soft tissue changes at the labrale superius. Patients with thin lips experienced nearly 3 times more advancement of the lips than do patients with thick lips for the same amount of bone movement. The incorporation of lip thickness into a multiple regression equation improved the correlation in all areas studied. [Copyright &y& Elsevier]

Summary: The incidence of diacapsular fracture of the mandibular condyle (DFMC) has increased in recent years. However, the specific modality of treatment which would provide maximum benefit and good results for adult patients of DFMC has been controversial. To evaluate and compare morphological changes of temporomandibular joint (TMJ) after open and closed treatments for DFMC, a sheep model of a type B DFMC was created by osteotomy. Eight sheep models of type B DFMC were randomly divided into 2 groups to receive closed treatment (Group 1) and open reduction and internal fixation (ORIF, Group 2), respectively, and morphological changes of TMJ were scored according to the radiological and anatomical criteria of scoring and compared between the 2 groups. Compared with Group 1 animals treated by the closed method, Group 2 animals treated with ORIF received significantly lower scores for morphological changes 12 weeks after treatment. We conclude that ORIF is more efficient than the closed functional treatment in restoring morphology of TMJ to treat type B DFMC. [Copyright &y& Elsevier]

Objective: Changes in posture are of concern because of their association with pain or impaired physical function. Previous studies that have used computer-aided video motion analysis systems to measure posture have been compromised by the use of problematic models of skin marker placement. This study aimed to quantify and compare sagittal spinal posture in standing and sitting between young and older adults using a two-dimensional PEAK Motus system and a revised skin marker model. Methods: Twenty-four healthy young adults and 22 healthy older adults volunteered for this study. The angles of the upper and lower cervical spine, thoracic spine, lumbar spine as well as the orientations of the head, neck, and pelvic plane with respect to an external reference were measured in the standing and sitting positions. Results: Compared to young adults, healthy older adults demonstrated a forward head posture, with increased lower cervical spine flexion and increased upper cervical extension in both positions. Older adults also sat with significantly increased thoracic kyphosis and decreased lumbar spine flexion. Conclusion: The angular relationship between adjacent spinal regions in the sagittal plane can be objectively quantified using image-based analysis. The concept that the anteroposterior tilt of the pelvis in standing dictates the lumbar and thoracic curves was supported by the correlations between these adjacent regions in both age groups. The model of skin marker placement used in this study can have a broader application as a clinical tool for image-based postural assessment. [ABSTRACT FROM AUTHOR]

Abstract: Objectives: To test the hypothesis that midline basicranial orientation and posterior cranial base length are discriminating factors between adults of different populations and its potential maxillo/mandibular disharmonies. Design: Twenty-nine 2D landmarks of the midline cranial base, the face and the mandible of dry skull X-rays from three major populations (45 Asians, 34 Africans, 64 Europeans) were digitized and analysed by geometric morphometrics. We used, first, MANOVA to test for mean shape differences between populations; then, principal components analysis (PCA) to assess the overall variation in the sample and finally, canonical variate analysis (CVA) with jack-knife validations (N =1000) to analyse the anatomical features that best distinguished among populations. Results: Significant mean shapes differences were shown between populations (P <0.001). CVA revealed two significant axes of discrimination (P <0.001). Jack-knife validation correctly identified 92% of 15,000 unknowns. In Africans the whole cranial base is rotated into a forward–downward position, while in Asians it is rotated in the opposite way. The Europeans occupied an intermediate position. African and Asian samples showed a maxillo/mandibular prognathism. African prognathism was produced by an anterior positioned maxilla, Asian prognathism by retruded anterior cranial base and increase of the posterior cranial base length. Europeans showed a trend towards retracted mandibles with relatively shorter posterior cranial bases. Conclusions: The results supported the hypothesis that basicranial orientation and posterior cranial base length are valid factors to distinguish between geographic groups. The whole craniofacial configuration underlying a particular maxillo-facial disharmony must be considered in diagnosis, growth predictions and resulting treatment planning. [Copyright &y& Elsevier]

Microcephalic osteodysplastic primordial dwarfism type II is a specific disorder characterized by severe intrauterine and postnatal growth retardation, acquired microcephaly, cerebrovascular abnormalities, progressive bone dysplasia, and a characteristic face. Whereas the diagnostic features of this syndrome are well-recognized, the neurologic aspects have not been clearly defined. We report on a detailed neurodevelopmental follow-up study of a new case of microcephalic osteodysplastic primordial dwarfism type II, followed from the first years of life to adolescence, and we discuss the neurocognitive features of our patient. We also review the neurologic aspects of this disorder compared with syndromes with overlapping phenotypes, such as microcephalic osteodysplastic primordial dwarfism types I and III and Seckel syndrome. [Copyright &y& Elsevier]

Abstract: The great barracuda, Sphyraena barracuda, is a voracious marine predator that captures fish with a swift ram feeding strike. While aspects of its ram feeding kinematics have been examined, an unexamined aspect of their feeding strategy is the bite mechanism used to process prey. Barracuda can attack fish larger than the gape of their jaws, and in order to swallow large prey, can sever their prey into pieces with powerful jaws replete with sharp cutting teeth. Our study examines the functional morphology and biomechanics of ‘ram-biting’ behavior in great barracuda where the posterior portions of the oral jaws are used to slice through prey. Using fresh fish and preserved museum specimens, we examined the jaw mechanism of an ontogenetic series of barracuda ranging from 20g to 8.2kg. Jaw functional morphology was described from dissections of fresh specimens and bite mechanics were determined from jaw morphometrics using the software MandibLever (v3.2). High-speed video of barracuda biting (1500framess−1) revealed that prey are impacted at the corner of the mouth during capture in an orthogonal position where rapid repeated bites and short lateral headshakes result in cutting the prey in two. Predicted dynamic force output of the lower jaw nearly doubles from the tip to the corner of the mouth reaching as high as 58N in large individuals. A robust palatine bone embedded with large dagger-like teeth opposes the mandible at the rear of the jaws providing for a scissor-like bite capable of shearing through the flesh and bone of its prey. [Copyright &y& Elsevier]

Abstract: Dynamic mathematical modelling is an invaluable method to help understand the biomechanics of the anatomically and functionally complex masticatory system. It provides insight into variables which are impossible to measure directly such as joint loads and individual muscle tensions, and into physical relationships between jaw structure and function. Individual parameters can be modified easily to understand their influence on function. Our models are constructed with best available structural and functional data, and evaluated against human jaw behaviour. Image data provide hard and soft tissue morphology and the jaw''s inertial properties. The drive to the system is provided by actuators which simulate active and passive jaw muscle properties. In whole-jaw modelling, muscle models which behave plausibly rather than mimic the ultra-structural cross-bridge interactions are common since they are computationally feasible. Whole-jaw models have recently incorporated flexible finite-elements to explore tissue distortion in the temporomandibular joint and tongue movements. Furthermore, the jaw has been integrated with laryngeal models to explore complex tasks such as swallowing. These dynamic models have helped better understand joint loading, movement constraints and muscle activation strategies. Future directions will include further incorporation of rigid and flexible model dynamics and the creation of subject-specific models to better understand the functional implications of pathology. [Copyright &y& Elsevier]

Abstract: Background: It is known that in vivo kinematics after total knee replacement is influenced by the design of the implant. The goal of this study was to show that the sagittal curvature of two different knee prostheses differing in geometric design predicts their in vivo motion behavior. Methods: Three-dimensional tibio-femoral displacements of two prosthesis designs (single radius vs. dual radius) were measured during knee extension under weight bearing conditions by in vivo video fluoroscopy. Finite helical axes were computed to represent the tibio-femoral motions. Angular deviation α and the spatial localization deviation δ were used to characterize the motions. Angular deviation is the angle between each incremental finite helical axis and the medio-lateral axis of the femoral component of the prosthesis. The spatial localization deviation is the distance between each finite helical axis and the center of the femoral component of the prosthesis. Statistical comparisons were performed using the median and the interquartile range of the angular deviation and the spatial localization deviation. Findings: The single-radius design showed finite helical axes concentrated at a single axis near to the medio-lateral axis of the femoral component. The angular and spatial localization deviation of the dual radius design were larger compared to the single radius design, exhibiting finite helical axes varying between two axes. Interpretation: Video fluoroscopy in combination with finite helical axis analysis proved to be suitable methods to evaluate the in vivo kinematical behavior of total knee arthroplasty, which can be useful for implant designers. Knowledge of in vivo kinematics can also provide surgeons with more background information about the total knee arthroplasty models they implant. [Copyright &y& Elsevier]

Abstract: A theoretically simple and computationally efficient method to extract the midsagittal plane (MSP) from volumetric neuroimages is presented. The method works in two stages (coarse and fine) and is based on calculation of the Kullback and Leibler’s (KL) measure, which characterizes the difference between two distributions. Slices along the sagittal direction are analyzed with respect to a reference slice to determine the coarse MSP. To calculate the final MSP, a local search algorithm is applied. The proposed method does not need any preprocessing, like reformatting, skull stripping, etc. The algorithm was validated quantitatively on 75 MRI datasets of different pulse sequences (T1WI, T2WI, FLAIR and SPGR) and MRA. The angular and distance errors between the calculated MSP and the ground truth lines marked by the expert were calculated. The average distance and angular deviation were 1.25 pixels and 0.63°, respectively. In addition, the algorithm was tested qualitatively on PD, FLAIR, MRA, and CT datasets. To analyze the robustness of the method against rotation, inhomogeneity and noise, the phantom data were used. [Copyright &y& Elsevier]

SUMMARY: Introduction: During the early development, numerous histological and morphometric changes occur in the cranial sutures the exact knowledge of which is of fundamental significance for understanding clinically relevant cranial anomalies. In this paper a histological and histomorphometric longitudinal study of the coronal, sagittal and lambdoid sutures in the rat is reported in relation to age. Material and methods: Forty-eight male Wistar rats (Rattus norvegicus Berkenhout) were raised under standard conditions. Eight animals each were sacrificed at defined time points (10, 14, 28, 42, 70, 98 days post partum) for specimen preparation. Histological preparations of the sagittal, coronal and lambdoid sutures were produced and examined morphologically and histomorphometrically (suture width, height, and area). Results: Histologically, three phases of sutural growth with characteristic structural features were found. Histomorphometry reveals a quasi linear increase in height from the 30th to the 98th day post partum. Suture width remained relatively constant in the area of dura mater and periosteum. Conclusion: The sutures of the test animals studied had a similar growth behaviour primarily consisting of an increase in height with almost constant width. The three-phases of development could be demonstrated histologically in all sutures. [Copyright &y& Elsevier]

Abstract: The remarkable mechanical prowess of the jaws of the bloodworm Glycera dibranchiata appears to be a consequence of a robust cross-linked network of organic molecules, notably melanin and proteins, as well as small amounts of unmineralized Cu and a Cu-based mineral. The present study focuses on the role of melanin. Mechanical properties of untreated jaws and the constituent melanin are probed through nanoindentation, both in air and underwater. Complementary information is obtained from density and porosity measurements and attempts at Cu removal from the jaws using EDTA, an effective metal chelator in most biological systems. In near-tip regions of the jaws, mechanical properties attain the highest values and diminish only slightly when wet (by 15–25%), in contrast to the behavior of other organic biomaterials. The melanin constituent contributes significantly to the mechanical integrity of the jaw; its hardness and elastic modulus are about half those of untreated jaws. Although melanin may be the dominant shape-determining component of the structure, it remains to be shown whether jaw assembly is mediated by protein deposition on a melanin scaffold or, conversely, by melanin deposition on a protein scaffold. The inability of EDTA to chelate Cu from the jaws and the relatively high density of the jaws and the melanin support the notion of a highly cross-linked molecular structure. Finally, based on the metric H 3/E 2 (H being hardness and E the Young’s modulus), the results suggest that the abrasion resistance of the jaws is superior to all engineering polymers and competitive with the hardest metallic alloys. [Copyright &y& Elsevier]

Abstract: Primary microcephaly is a developmental defect of the brain characterized by severely reduced brain size but an absence of other overt abnormalities. Mutations in several loci have been linked to primary microcephaly. The underlying genes for two of these were recently identified as CDK5RAP2 and CENPJ. Here, we focus on CDK5RAP2 and show that the protein evolutionary rate of this gene is significantly higher in primates than rodents or carnivores. We further show that the evolutionary rate within primates is particularly high in the human and chimpanzee terminal branches. Thus, the pattern of molecular evolution seen in CDK5RAP2 appears to parallel, at least approximately, that seen in two other previously identified primary microcephaly genes, microcephalin and ASPM. We also briefly discuss CENPJ, which similarly exhibits higher rate of protein evolution in primates as compared to rodents and carnivores. Together, the evolutionary patterns of all four presently known primary microcephaly genes are consistent with the hypothesis that genes regulating brain size during development might also play a role in brain evolution in primates and especially humans. [Copyright &y& Elsevier]

Abstract: Background: Motion at the midfoot joints can contribute significantly to overall foot motion during gait. However, there is little information regarding the kinematic coupling relationship at the midfoot. The purpose of the present study was to determine whether the coupling relationship at the midfoot and subtalar joints was affected when step width was manipulated during running. Methods: Twelve subjects ran over-ground at self-selected speeds using three different step widths (normal, wide, cross-over). Coupling at the midfoot (forefoot relative to rearfoot) and subtalar (rearfoot relative to shank) joints was assessed using cross-correlation techniques. Findings: Rearfoot kinematics were significantly different from normal running in cross-over running (P <0.05) but not in wide running. However, coupling between rearfoot eversion/inversion and shank rotation was consistently high (r >0.917), regardless of step width. This was also the case for coupling between rearfoot frontal plane motion and forefoot sagittal plane (r <−0.852) and forefoot transverse plane (r >0.946) motion. There was little evidence of coupling between rearfoot frontal plane motion and forefoot frontal plane motion in any of the conditions. Interpretation: Forefoot frontal plane motion appeared to have little effect on rearfoot frontal plane motion and thus, had no effect on motion at the subtalar joint. The strong coupling of forefoot sagittal and transverse plane motions with rearfoot frontal plane motion suggests that forefoot motion exerts an important influence on subtalar joint kinematics. [Copyright &y& Elsevier]

Abstract: Sagittal suture has a complex pattern which is formed by collision of edges of left and right growing parietal bones. There is fibrous tissue between the left and the right parietal bones, where an osteoblast becomes a basis of ossification. We simulate the growth and the collision of the bone by using the Eden growth model in 3-dimensional space (3D) and obtain a pattern which is similar to the sagittal suture on the inner surface as well as on the outer surface of the calvaria. [Copyright &y& Elsevier]

Nijmegen breakage syndrome (NBS) is a chromosomal-instability syndrome associated with cancer predisposition, radiosensitivity, microcephaly, and growth retardation. The NBS gene product, NBS1, is a component of the MRE11-RAD50-NBS1 (MRN) complex, a central player associated with double strand break (DSB) repair. In response to radiation, NBS1 is phosphorylated by ATM, and the MRN complex relocalizes to form punctate nuclear foci for DNA repair. NBS1 controls both the nuclear localization of the MRN complexes and radiation-induced focus formation. We report here that the KPNA2 (importin α1) is important for the normal nuclear localization of the MRN complex and its proper formation of the nuclear loci. KPNA2 is the only member of the importin family that physically interacts with NBS1, and the KPNA2-mediated nucleus localization sequence (NLS) is mapped to amino acid residues 461–4.67 of NBS1 that is sufficient for both the interaction with KPNA2 and the proper nuclear localization. Inhibition of KPNA2 or blockage of the KPNA2 interaction with NBS1 results in a reduction of radiation-induced nuclear focus accumulation, DSB repair, and cell cycle checkpoint signaling of NBS1. Collectively, our results strongly suggest that an interaction with KPNA2 contributes to nuclear localization and multiple tumor suppression functions of the NBS1 complex. [ABSTRACT FROM AUTHOR]

Abstract: Bone loss may affect the structure of cancellous bone. But its effect on trabeculae with different characteristics, like rods and plates, is not accurately known. This study analyzes the effect of bone loss on individual rod-like and plate-like trabeculae. 94 specimens were obtained from mandibular condyles from both dentate and edentate humans and scanned with a micro-CT scanner. The bone volume fraction (BV/TV) of these specimens ranged from 7% to 30%. Next, the rod-like and plate-like trabeculae were identified with an especially developed algorithm. Plate volume fraction (PV/TV), rod volume fraction (RV/TV), plate thickness, rod thickness, number of plates, and number of rods were determined. In individual specimens, the thickness of the rods ranged from 40 μm to 180 μm, while the thickness of the plates ranged from 40 μm to 300 μm. In every specimen, the thickness of the plates was larger than the thickness of the rods. Statistical analysis revealed that PV/TV was proportional (r = 0.98, P &#60; 0.001) and RV/TV inversely proportional (r = −0.45, P &#60; 0.001) to BV/TV. Also the thickness of the plates correlated with BV/TV (r = 0.62, P &#60; 0.001), while the thickness of the rods (mean = 90 μm, SD = 7 μm) remained constant (r = −0.09, P = 0.378). A four-fold reduction of the bone volume fraction was accompanied by a three-fold reduction of the number of plates and a 40% reduction of their thickness, but also by a three-fold increase in the number of rods and RV/TV. It was concluded that the effect of bone loss on plate-like trabeculae was opposite to its effect on rod-like trabeculae. Remarkably, the thickness of the rods (90 μm) was independent of the bone volume fraction. This suggests that there is a minimal thickness for trabeculae. [Copyright &y& Elsevier]

Abstract: This study was designed to assess skeletal stability after bilateral sagittal split ramus osteotomy (BSSO) and fixation with a poly-l-lactic acid (PLLA) plate, as compared to that after BSSO and fixation with a titanium plate, and to analyze the change in the condylar long axis after these procedures. The study group comprised 40 patients who had mandibular prognathism (20, titanium group; 20, PLLA group). The groups were randomized to show similar distributions of preoperative SNB. All patients underwent BSSO setback by the Obwegeser method. Fixation was done with bent titanium plates or bent PLLA plates, applied in a similar manner. Lateral, frontal, and submental–vertical cephalograms were analyzed preoperatively and postoperatively. The maximum mouth opening range and the incidence of temporomandibular disorders were also evaluated. There was no significant difference in the right condylar angle or width between the two groups, but the left condylar angle and width, gonial angle, and ramus inclination differed significantly between them (P <0.05). SNA, SNB, and ANB were similar in both groups. There was no significant difference between the groups in maximum mouth opening range or temporomandibular disorders. We conclude that the change in condylar angle after BSSO and fixation with a titanium plate is greater than that after BSSO and fixation with a PLLA plate, but skeletal stability related to the occlusion is similar for the two procedures. [Copyright &y& Elsevier]

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Summary: We report the case of a 3.5-year-old boy who presented with truncal ataxia, microcephaly and delayed global development in infancy. Hypoplasia of cerebellum and corpus callosum and delayed myelination were found on brain MRI. Failure to thrive, sparse hairs and dystrophic nails became evident at the age of 2 years. He subsequently developed bleeding tendency, thrombocytopenia and hypocellularity on bone marrow examination leading to a diagnosis of dyskeratosis congenita. Impaired pain perception with slowing of nerve conduction velocities was demonstrated, suggesting a mild peripheral neuropathy. To the best of our knowledge, peripheral neuropathy has never been reported as a feature of the congenital form of dyskeratosis congenita. [Copyright &y& Elsevier]

While the lateral occipital complex (LOC) has been shown to be implicated in object recognition, it is unclear whether this brain area is responsive to low-level stimulus-driven features or high-level representational processes. We used scrambled shape-from-motion displays to disambiguate the presence of contours from figure-ground segregation and to measure the strength of the binding process for shapes without contours. We found persisting brain activation in the LOC for scrambled displays after the motion stopped indicating that this brain area subserves and maintains figure-ground segregation processes, a low-level function in the object processing hierarchy. In our second experiment, we found that the figure-ground segregation process has some form of spatial constancy indicating top–down influences. The persisting activation after the motion stops suggests an intermediate role in object recognition processes for this brain area and might provide further evidence for the idea that the lateral occipital complex subserves mnemonic functions mediating between iconic and short-term memory. [Copyright &y& Elsevier]

Scolecodonts, polychaete jaws, generally occur abundantly in Silurian shallow marine successions and are known from all continents except Antarctica. The assemblages are typically characterized by taxa with labidognath, placognath and prionognath type jaw apparatuses. They commonly include species of Kettnerites &Zbreve;ebera, 1935, Oenonites Hinde, 1879, Mochtyella Kielan-Jaworowska, 1961, Protarabellites Stauffer, 1933, Atraktoprion Kielan-Jaworowska, 1962, Pistoprion Kielan-Jaworowska, 1966, Vistulella Kielan-Jaworowska, 1961, Xanioprion Kielan-Jaworowska, 1962, Kalloprion Kielan-Jaworowska, 1962, and Leptoprion Kielan-Jaworowska, 1966. Less common genera, such as Hadoprion Eriksson and Bergman, 1998, Symmetroprion Kielan-Jaworowska, 1966 and Rhytiprion Kielan-Jaworowska, 1966, generally are recorded only from very large collections and/or suitable facies. Many of the common genera, as well as a few species, have been identified in several regions, particularly in Baltica and Laurentia, and evidently had a broad, intercontinental distribution. However, the scolecodont record from regions at higher paleolatitudes, i.e. Gondwana and peripheral paleoplates, is meager.In the famous latest Llandovery to latest Ludlow succession of Gotland, Sweden, scolecodonts are one of the most common microfossil groups, with abundances reaching thousands of specimens/kg rock. Based on an extensive collection, approximately one hundred jawed polychaete species belonging to at least 28 genera and a dozen families have been identified. Polychaetaspids, paulinitids and mochtyellids dominate. The exceptionally rare genus Synclinophora Eisenack, 1975, may belong to the family Oenonidae. If so, this is the only extant family represented in Silurian strata. The diversity patterns and temporal and stratigraphic distribution related to facies reveal that the assemblages house eurytopic as well as stenotopic taxa. Both long-ranging taxa, embracing the entire succession and beyond, and short-ranging taxa occur. Like other metazoan groups, jawed polychaetes were affected by the documented Silurian extinction events. During the globally recognized late Ludlow Lau Event, approximately one third of the identified polychaete taxa went extinct, and some lineages show Lazarus gaps on Gotland. [Copyright &y& Elsevier]

Objective: To evaluate the cavernous sinuses with dynamic magnetic resonance (MR) imaging in patients with Tolosa–Hunt syndrome (THS). Methods: The sellar and parasellar regions of five patients with THS and 12 control subjects were examined with dynamic MR (1.5 T) imaging in the coronal plane. Dynamic images were obtained with spin-echo (SE) sequences in three patients, and with fast spin-echo (FSE) sequences in two patients and control subjects. Conventional MR images of the cranium including sellar and parasellar regions were also obtained on T1-weighted pre- and post-contrast SE, and T2-weighted FSE sequences in the coronal plane. Results: MR images revealed affected cavernous sinus with bulged convex lateral wall in three patients and concave lateral wall in two patients. In all control subjects, cavernous sinuses were observed with concave lateral wall. The signal intensity on T1- and T2-weighted images and contrast enhancement on post-contrast images of the affected cavernous sinuses in patients were similar to those of the unaffected cavernous sinuses in patients and control subjects. The dynamic images in all patients disclosed small areas adjacent to the cranial nerve filling-defects within the enhanced venous spaces of the affected cavernous sinus, which showed slow and gradual enhancement from the early to the late dynamic images. No such gradually enhancing area was observed in control subjects except one. The follow-up dynamic MR images after corticosteroid therapy revealed complete resolution of the gradually enhancing areas in the previously affected cavernous sinus. Conclusion: Dynamic MR imaging may facilitate the diagnosis of THS. [Copyright &y& Elsevier]

Thetalpid3 chicken mutant has a pleiotropic phenotype including polydactyly and craniofacial abnormalities. Limb polydactyly intalpid3 suggests a gain of Hedgehog (Hh) signaling, whereas, paradoxically, absence of midline facial structures suggests a loss of Hh function. Here we analyze the status of Shh signaling in thetalpid3 mutant head. We show thatShhexpression domains are lost from thetalpid3 head—in hindbrain, midbrain, zona limitans intrathalamica, and stomodeal ectoderm—and that direct targets of Hedgehog signaling,Ptc1,Ptc2, andGli1, are also absent even in areas associated with primaryShhexpression. These data suggest that thetalpid3 mutation leads to defective activation of the Shh pathway and, furthermore, that tissue-to-tissue transduction ofShhexpression in the developing head depends on Hh pathway activation. Failure to activate the Shh pathway can also explain absence of floor plate andHnf-3β andNetrin-1expression in midbrain and hindbrain and absence ofFgf-8expression in commissural plate. Other aspects of gene expression in thetalpid3 head, however, suggest misspecification, such as maintenance of floor plate-like gene expression in telencephalon. In branchial arches and lower jaw, whereShhis expressed, changes in expression of genes involved in patterning and mesodermal specification suggest both gain and loss of Hedgehog function. Thus, analysis of gene expression intalpid3 head shows that, as intalpid3 limb, expression of some genes is lost, while others are ectopically expressed. Unlike the limb, many head regions depend on Hh induction of a secondary domain ofShhexpression, and failure of this induction intalpid3, together with the inability to activate the Shh pathway, explain the loss-of-function head phenotype. This gene expression analysis in thetalpid3 head also confirms and extends knowledge of the importance of Shh signaling and the balance between activation and repression of Shh targets in many aspects of craniofacial morphogenesis. [ABSTRACT FROM AUTHOR]

Microcephalin (MCPH1) is the first gene identified among at least six loci that contribute to the autosomal recessive disease, primary microcephaly. MCPH1, like NFBD1/MDC1, 53BP1, and BRCA1, encodes a protein with twin carboxyl-terminal BRCT domains (PTCB). (Here, we report that Mcph1 forms ionizing radiation-induced foci. Down-regulation of Mcph1, like other PTCBs, by siRNA, impairs ionizing radiation-induced intra-S-phase and G2/M checkpoints. Inhibition of the expression of Mcph1 decreases both protein and transcript levels of endogenous Brca1 but not exogenous Brca1. Mcph1 inhibition also decreases both endogenous and heterologous Chk1 transcripts and protein. We conclude that Mcph1 is involved in DNA damage-induced cellular responses, and we propose that regulation of Brca1 and/or Chk1 by Mcph1 may contribute to these cellular responses. [ABSTRACT FROM AUTHOR]

In its third decade of development, neuronavigation has matured from pure trajectory planning to an instrument that can provide instant anatomical orientation on basis of three-dimensional (3D) images that closely match the microsurgical field at hand. Functional tissue properties may be incorporated in these images and volumetric rendering allows for visualization of all significant anatomical landmarks in the surgical path in one single view by modulating the opacity of overlying tissue layers. We have explored the possibilities of image guidance based on multimodal 3D images in more than 200 neurosurgical cases, with pathologies ranging from supratentrial tumors to lesions in the skull base and craniocervical junction. MRI (1.5 and 3 T), fMRI, positron emission tomography (PET), computed tomography (CT), CT angiography, and postmyelographic CT have been employed. Target registration error (TRE) and intraoperative shift have been calculated, and time and cost efficiency were estimated. 3D imaging was advantageous for fast orientation in complex morphology (gyri, sulci, dural sinuses, Circle of Willis, nasal cavity and paranasal sinuses), especially in cases where rotation of the operative field of view was necessary during the approach. Depiction of anatomical detail was limited by image resolution and tissue contrast. Virtual and real microscopic individual anatomy could permanently be correlated during surgery. Profound anatomical knowledge as well as repeated assessment of navigation errors was indispensable to detect accuracy changes during surgery. While guidance based on three-dimensional images cannot replace anatomical knowledge and surgical experience it offers a déjà vu experience for the neurosurgeon when the 3D model truly matches the surgical path and field. It relieves surgeons of the task of having to mentally reconstruct and rotate triaxial 2D images, extends their field of view beyond tissue barriers and provides functional information on the operative field that is otherwise invisible and inaccessible. Volumetric anatomical and functional identification based on image-guidance in the operating suite may expand surgical vision and improve patient safety—a major factor in cost-efficiency calculations. [Copyright &y& Elsevier]

The milling of bone is a time-consuming and straining effort during surgery at the cranial vault. In order to determine possible advantages of a robotic system, the registration of different milling parameters during defined surgical procedures was the aim of this study. Eleven neurosurgeons were asked to mill a bovine scapula. The task consisted of geometric figures (one line and a circle) that had to be milled in a depth of 3 mm. Main focus was laid on the accuracy of the milling. In addition, the registered parameters such as forces, temperature and speed will be used as a reference for the design and validation of the robotic system. The same task was done by a robotic (hexapod) system, constructed at the Helmholtz-Institute Aachen (HIA). In comparison with the surgeon, the robotic system showed a higher accuracy at a greater velocity. The forces and temperatures showed minor differences. If further test results are consistent, it would be advantageous to use a robotic system to perform large craniectomies, especially in cosmetically relevant areas due to its advantage in accuracy and speed compared to a surgeon. [Copyright &y& Elsevier]

Target point accuracy is a main issue in functional stereotactic procedures for the implantation of deep brain stimulators. Next to standard stereotactic methods, intraoperative microelectrode recordings help to reach the target point. While currently up to 5 electrodes are used, we introduce a new 32-channel system. Our probes allow for recording 32 neural signals alongside up to 1 cm of the planned trajectory simultaneously. The signal evaluation is supported by customized analysis and visualization tools contained in our navEgate DAQ software. The acquisition software has access to the navEbase database that holds characteristic signal features with respect to their anatomic origin. Currently recorded signals can be compared against nominal values from the database. While preclinical studies of our system are on the way, we are convinced that the possibility to record neural depth profiles will fasten intrapoerative microelectrode recordings, and that the feedback from navEbase will assist teams in questionable cases. [Copyright &y& Elsevier]

Medical and scientific knowledge is not intrinsically different from other kinds of knowledge and has gone through the same processes in terms of its development. As a profession, medicine achieved its dominance in the 19th century and has subsequently consolidated its power base. A socio-historical perspective shows us that medicine has no more and no less fraud, heresy, schism, and relative knowledge than any other equivalent forms of knowledge. Orthodox medicine emerged from a number of healing systems in the 19th century by claiming the superiority and consequent authority of the biomedical model and its special relationship to laboratory science. This process has been seen by some to resemble the growth of religious orthodoxy and the emergence of alternative beliefs with the dissenting medical systems, based on different paradigms, becoming analogous to religious sects. An increasing body of opinion rejects the notion of “objective” knowledge and sees medical knowledge and practice as “socially constructed”. An examination of HIV/AIDS measurement and 19th century craniology and contagion and anti-contagion theories indicates processes which are “contextual” rather than “objective”. Heresy and schism are natural concomitants of socially constructed knowledge, functioning as providers of impetus and change and, as such, are to be welcomed as non-orthodox challenges. [Copyright &y& Elsevier]

It is widely believed that rapid growth of the human brain generates tensile strain in cranial sutures, and that this strain influences the rate of bone deposition at the sutural margins during development. We developed general theoretical techniques for estimating sutural bone deposition rate and strain magnitude during mammalian cranial development. A geometry-based analysis was developed to estimate sutural bone deposition rate. A quasi-static stress analysis was developed to estimate sutural strain magnitude. We applied these techniques to the special case of normal cranial development in humans. The results of the bone deposition rate analysis indicate that average human sutural bone deposition rate is on the order of 100 μm/day at 1 month of age and decreases in an approximately exponential fashion during the first 4 years of life. The results of the strain analysis indicate that sutural strain magnitude is highly dependent on the assumed stiffness of the sutures, with estimated strain at 1 month of age ranging from approximately 20 to 400 microstrain. Regardless of the assumed stiffness of the sutures, the results indicate that sutural strain magnitude is small and decreases in an approximately exponential fashion during the first 4 years of life. The finding that both sutural bone deposition rate and strain magnitude decrease with increasing age is consistent with quasi-static tensile strain in sutures influencing sutural osteoblast activity in a dose-dependent manner. However, the small magnitude of the predicted strains suggests that tissue level strains in sutures may be too small to directly influence osteoblast biology. In light of these results, we suggest other biomechanical mechanisms, such as a tension-induced angiogenic environment in the sutures or mechanotransduction in the underlying dura mater, through which tension across sutures may regulate the rate of bone deposition in sutures. [Copyright &y& Elsevier]

Several large suid cranial remains attributed to Microstonyx major are part of a new Hipparion Fauna collection from the Hezheng area, Northern China. The new material confirms the presence of Microstonyx in the late Miocene of the area. The Chinese form belongs to a small-sized eastern population with reduced premolar row and clear sexual bimodality. Statistical comparison shows that Microstonyx major was a polymorphic species and reinforces recognition of Hippopotamodon as a separate genus, defined by relatively stout premolars resulting from a different underlying pattern of allometric growth. The presence of Microstonyx in North China and the distinct suid assemblage that lived there suggest biogeographic connections between Northern China and Western Eurasia in contrast to isolation from Southern China and the Indian subcontinent. The suid fauna of the late Miocene of Northern China seems to have been restricted to the later, more humid phase represented by the Red Clay faunas. [Copyright &y& Elsevier]

Background: Small subcortical infarct (SSI) occurs more frequently among Chinese than Caucasians. Apart from small vessel disease, SSI is also associated with intracranial large artery disease. We aimed to study the frequency of SSI with and without intracranial large artery disease among Chinese stroke patients. Methods: Magnetic resonance imaging (MRI), magnetic resonance angiography (MRA), and diffusion weighted imaging (DWI) were performed among consecutive Chinese stroke patients admitted to our acute stroke unit over a 6-month period. Results: Among the 257 patients with ischemic stroke, 71 patients (27.6%) had SSI. Twelve patients (16.9%) had relevant intracranial large artery disease and three patients (4.2%) had lone relevant extracranial carotid artery disease. No patient had an identifiable cardiac embolic source or other miscellaneous cause. Excluding patients with relevant intracranial large artery disease and extracranial carotid artery disease, the frequency of SSI associated with presumed small vessel disease among patients with ischemic stroke was 21.7%. Patients with SSI associated with intracranial large artery disease had greater number of acute infarcts and slightly greater stroke severity and cognitive impairment than those with presumed small vessel disease. Conclusion: Our present study suggests that the higher frequency of SSI among Chinese may be in part related to a higher frequency of intracranial large artery disease rather than to a higher frequency of small vessel disease. [Copyright &y& Elsevier]

: PurposeTo evaluate the precision of using digitally reconstructed radiographs (DRRs) of either 3 mm or 6 mm slice separation vs. using simulator images for the setup verification of patients receiving CT planned conformal radiotherapy to the prostate. To calculate the transfer error between CT and simulator.: Methods and materialsTwenty patients were CT scanned (3 mm slice spacing/width). DRRs were generated for both 3 mm (DRR 3) and 6 mm (DRR 6) separations. DRRs and a simulator image of an anterior and a lateral field were used as reference images. Five observers matched each of the reference images to treatment images using the Theraview “Target check” facility. It was assumed that poorer images would lead to a loss of precision of field placement estimations (FPE) between observers. The study was designed to detect a difference greater than 1.5 mm2 in the precision of image placement. The transfer error was the mean difference in the setup error derived from the DRRs and the simulation films.: ResultsThe precision of evaluations for simulator films and 3 mm DRRs were similar. There was a trend for the DRR 6 mm to achieve less precise results which was greatest for craniocaudal examinations (variance: simulator 1.5 mm2, DRR6 2.8 mm2, p = 0.17), but this did not reach statistical significance. A range of transfer errors was identified, with standard deviations ranging from 1.7 to 4.2 mm. There was evidence of a significant systematic bias in anterior craniocaudal (1.3–1.9 mm, p < 0.004) and anterior posterior (−1.9 mm, p = 0.027).: ConclusionThe precision of setup evaluations using DRRs is similar to that achieved by using simulator fields when planning conformal prostate radiotherapy. The use of DRRs could reduce systematic errors introduced in the planning process. [Copyright &y& Elsevier]

Objectives: The aim of this investigation was to describe the dental and craniofacial characteristics of patients with amelogenesis imperfecta (AI).Methods: The study group included 43 patients(33 female and 10 male) with a mean age of 11.4+/-2.6 years. A panoramic and a cephalometric radiograph were obtained from each of these patients. Clinically AI cases were divided into four main groups according to Witkop. All patients were evaluated for chronological, bone and dental age. The patients who had severe retarded bone age were evaluated for plasma growth hormone(GH) concentrations.Results: Dental and bone ages were retarded with respect to chronological age in five patients. Dental maturity and tooth eruption were not age- appropriate in some of our patients. In type III AI patients a delay in skeletal age was observed. Severe late eruption was seen in 3 patients, severe delay in dental maturity was noted in patients with type IV AI. Dental age was clinically lower in GH-deficient subjects, and skeletal age was consistently more retarded than dental age when compared to chronological age. Anterior open bite was present in both primary and permanent dentitions of 50% of the patients with type I AI, 30.8% of the patients with type II AI, and 60% of type III AI.Conclusion: It is concluded that the primary structure for the classification of AI be based on the mode of inheritance, with the clinical and radiographic appearances (and any other features such as systemic findings) being the secondary discriminators. [ABSTRACT FROM AUTHOR]

: BackgroundKnowing the location of the venous sinuses in the combined lateral posterior fossa and lateral cranial base approach is important to prevent their inadvertent injury. The identification of surface landmarks related to these structures is useful in planning such surgical approaches.: MethodsTwelve injected adult cadaver specimens and 10 dried skulls were used to study the relationship of the venous sinuses to various surface anatomic structures.: ResultsThe asterion was not clearly seen in 60% of the studied cadaver sides. The asterion was always clearly seen in the dry skull preparations. The upper margin of the superior nuchal line was found to range from 1.5 mm to 14 mm inferior to the lower margin of the lateral transverse sinus. In 85% of our specimens, the mastoid groove was found to completely overlie the sigmoid sinus.: ConclusionsThe asterion was found to be variable in its anatomic relations to other identifiable structures. This variability in relation to other posterior fossa bony landmarks limits its overall usefulness as a consistently stable marker for intracranial structures. The first and most superolateral burr hole for lateral posterior fossa procedures can be safely placed 1 cm below the superior nuchal line and 1 cm medial to the top of the mastoid groove. A burr hole in this location will avoid the transverse and sigmoid sinuses, as well as the transverse-sigmoid junction, yet will be high enough and lateral enough to provide easy exposure of these venous sinuses for all lateral posterior fossa procedures. [Copyright &y& Elsevier]

Because the mouse is now the main model for developmental research of all types, it is important to understand the basic developmental pattern of various organs. The first aim of the present study was to establish normal prenatal developmental standards of the cartilaginous nasal capsule during embryonic development of the mouse. For this purpose we have performed sagittal and coronal sections ranging from E12.5 to E18.5 in gestation age. The primordia of the nasal septal cartilage is recognizable around the 14th embryonic day as demonstrated by the metachromatic toluidine blue staining and by immunostaining of type II collagen. Northern blot analysis of the transcription factors Cart-1 and Sox-9 indicated maximum mRNA levels at E12.5 then a decreased expression during the following days of gestation. Type II collagen and aggrecan mRNA levels are constant during the embryonic period. In the second part of this study, we have established a primary culture system where chondrocytes were isolated from E.18 mouse embryo nasal septum. The purpose of this second part was to assess if chondrocytes could further differentiate in vitro until the hypertrophic phase and matrix mineralization. After the condensation phase, the cells synthesize an extracellular matrix including type II collagen and aggrecan. Progressively, typical cartilaginous nodules composed of clusters of round cells are visible, then increase in size and finally mineralize at day 12 of culture. Cart-1 and Sox-9 mRNA levels remain constant throughout the cultures, whereas type II collagen and aggrecan gradually decrease. Ultrastructural observations of the nodules show typical chondrocytes embedded in a dense network of fibers with matrix vesicles and mineralized foci. Other ultrathin sections revealed the presence of chondrons, typical of hyaline cartilage. Results from this study provide useful tools to further investigate morphogenesis and differentiation of the cartilaginous nasal capsule, and could in the future serve as a basic developmental standard. [Copyright &y& Elsevier]

Purpose: To investigate outcome and toxicity after fractionated stereotactic radiation therapy (FSRT) in patients with craniopharyngiomas.Methods and Materials: Twenty-six patients with craniopharyngiomas were treated with FSRT between May 1989 and February 2001. Median age was 33.5 years (range: 5–57 years). Nine patients received FSRT after surgery as primary treatment, and 17 patients were irradiated for recurrent tumor or progressive growth after initial surgery. Median target dose was 52.2 Gy (range: 50.0–57.6 Gy) with conventional fractionation. Follow-up included MRI and neurologic, ophthalmologic, and endocrinologic examinations.Results: The median follow-up was 43 months (range: 7–143 months). The actuarial local control rate and actuarial overall survival rates were 100% and 100%, respectively, at 5 years and 100% and 83%, respectively, at 10 years. Four patients showed complete response, 14 patients showed partial response, and 8 patients remained stable. In 5 patients, vision improved after radiation therapy. Acute toxicity was mild. One patient required cyst drainage 3 months after radiotherapy. Late toxicity after radiotherapy included impairment of hormone function in 3 out of 18 patients at risk. We did not observe any vision impairment, radionecrosis, or secondary malignancies.Conclusions: FSRT is effective and safe in the treatment of cystic craniopharyngiomas. Toxicity is extremely low using this conformal technique. [Copyright &y& Elsevier]

Substituting ferrets for rats and dogs as animal models for craniofacial research is favourable because of the similarity of many of the ferret’s anatomical, metabolic and physiological features to those of man. Other advantages are cost-effectiveness and possibly less ethical controversy. However, information on the dental chronology of ferrets needs to be supplemented if this animal is to be promoted as an alternative model. Dental development was here examined in 16 ferrets (eight males, eight females) from three litters at between 12 and 90 days of age. Dental eruption and exfoliation were assessed and recorded every second day. The sequence of eruption of deciduous and permanent teeth was determined and data were analysed statistically. Also, any sex-related differences in eruption and exfoliation ages were defined. No deciduous incisors were observed to erupt in this group of animals. Other deciduous teeth erupted between the 19th and 31st postnatal days, and exfoliated between days 51 and 76. The time of eruption of the permanent teeth ranged from 42 to 77 days, in accordance with the stage of the mixed dentition. The female ferrets were generally ahead of the males in the exfoliation age of their deciduous teeth and the eruption age of their permanent teeth, but this, a sex difference did not apply to the eruption age of the deciduous teeth. These extended basic data might facilitate the introduction of this alternative experimental animal into craniofacial research. [Copyright &y& Elsevier]

Bone osteonecrosis of the jaws (BONJ) is prevalent when diseases are treated with high bisphosphonate doses. The mouth is unique in that it has epithelial covered bony protuberances jutting into an infective environment. Should epithelium over these bony prominences be disrupted, abraded or ulcerated by trauma, extraction or therapy, not only will the mucosa not heal, but in vulnerable cases, where less-vital bone is present, there is development of BONJ. BONJ development is explained by BP’s depleting available calcium ions from healthy functioning of epithelial gap junctions and disrupting the balance between osteogenesis and osteoclasis. [ABSTRACT FROM AUTHOR]

We report a deployment technique that eliminates “watermelon seeding” of the “giant” Palmaz stent in the treatment of type IA endoleak after endovascular abdominal aneurysm repair. A 5010 Palmaz stent (Cordis Corp, Miami Lakes, Fla) is asymmetrically hand-crimped on an appropriately sized valvuloplasty balloon that assures that the proximal (cranial) aspect will deploy first. A long 16 to 20F sheath is placed distal to the target area. Once the balloon and stent assembly is in position, the sheath is partially retracted to allow only the proximal (cranial) half of the balloon to expand, flaring the unsheathed proximal stent. The expanded proximal balloon prevents cranial stent migration. The sheath prevents distal (caudal) stent migration. Full retraction of the sheath allows the distal balloon and stent to expand, completing the stent deployment. [Copyright &y& Elsevier]