[Effects of axis congruance between skull-equilibrated mounted maxillary models and skull-referenced mounted mandibular models].
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These experimental studies of skull fractures in the temporal region were carried out in co-operation the Faculty of Engineering and the Department of Neurosurgery of Tokyo University. 15 dry human skulls were statically compressed in the bitemporal direction. The results of our experiments are as follows: 1) The forces necessary to produce the first fracture (seperations of the parietotemporal suture) are between 135 kg and 385 kg. (average; 258 kg) 2) The forces necessary to produce the second fractures (true fractures) are between 195 kg and 550 kg. (average; 356.3 kg) 3) The decreases of the inner diameters of skulls from pre-examination to the first fracture are between 0.65 mm and 1.85 mm. 4) The decreases of the inner diameters of skulls from pre-examination to the second fracture are between 1.56 mm and 4.5 mm. 5) The forces necessary to reduce the inner diameters of skulls by 1 milimeter are between 85 kg/mm and 380 kg/mm. (average; 221 kg/mm) The forces necessary to produce a fracture in the temporal region are much less than the forces necessary to do so in the frontal region. In deforming the skull, it is necessary to apply much greater force to the frontal region than it is to the temporal region. The relation between the skull's age and the minimal force to produce the skull fracture is not clear from the results of these experiments. The weights of the skulls were directly related to the minimal force necessary to produce skull fractures. Breaks in the inner table preceded those of the outer table when linear fractures occurred over the compressed area. when depressed fractures formed in the same area, the outer table was broken before the inner table. When the linear fractures formed far from the same area, the outer table was broken before the inner table. From our investigations on sports injuries, those players who died after being hit by golf balls or baseballs showed the same clinical courses as in typical extradural hematoma. Plain X-ray examinations of those fataly injured players did not reveal any skull fractures. Plain X-ray examinations of fractured skulls often failed to reveal the lesion unless the bone fracture was widely separated. On the basis of the above results, it would appear that routine skull films using either anterior-posterior or lateral projections are inadequate for the diagnosis of skull fractures. We have had good results in the examination of skull fracture by using the stereo X-ray method.
Seven Etruscan skulls were found in Corneto Tarquinia in the years 1881 and 1882 and were given as present to Rostock's anatomical collection in 1882. The origin of the Etruscans who were contemporary with the Celts is not yet clear; according to Herodotus they had emigrated from Lydia in Asia Minor to Italy. To fit the Etruscan skulls into an ethnological grid they were compared with skeletal remains of the first thousand years B.C. E. All skulls were found to be male; their age ranged from 20 to 60 years, with an average age of about thirty. A comparison of the median sagittal outlines of the Etruscan skulls and the contemporary Hallstatt-Celtic skulls from North Bavaria showed that the former were shorter and lower. Maximum skull length, minimum frontal breadth, ear bregma height, bizygomatical breadth and orbital breadth of the Etruscan skulls were statistically significantly less developed compared to Hallstatt-Celtics from North Bavaria. In comparison to other contemporary skeletal remains the Etruscan skulls had no similarities in common with Hallstatt-Celtic skulls from North Bavaria and Baden-Württemberg but rather with Hallstatt-Celtic skulls from Hallstatt in Austria. Compared to chronologically adjacent skeletal remains the Etruscan skulls did not show similarities with Early Bronze Age skulls from Moravia but with Latène-Celtic skulls from Manching in South Bavaria. Due to the similarities of the Etruscan skulls with some Celtic skulls from South Bavaria and Austria, it seems more likely that the Etruscans were original inhabitants of Etruria than immigrants.
This study was conducted to compare the effects of intravenous fentanyl and intravenous fentanyl combined with bupivacaine infiltration on the hemodynamic response to skull pin insertion. 120 ASA I-II patients scheduled for elective craniotomy were included. The fentanyl group (group F, n = 60) received fentanyl during induction and prior to skull pin insertion (2 and 1 microg . kg, respectively). The fentanyl-bupivacaine group (group FB, n = 60) received the same doses of fentanyl as well as scalp infiltration with 0.25% bupivacaine. The heart rate (HR) was not significantly different between the groups. HR, at 5 minutes after skull pin insertion in the group F and at 1 and 5 minutes after skull pin insertion in group FB, significantly decreased in comparison to the baseline values (P < 0.05). In both groups, HR at 1 and 5 minutes after skull pin insertion was significantly lower than HR just before skull pin insertion (P < 0.05). In group FB, the mean arterial pressure (MAP) at 1 and 5 minutes after skull pin insertion were significantly lower than that in group F (P < 0.05). In group F, MAP at 1 minute after skull pin insertion was higher than that of just before skull pin insertion (P < 0.05); however, MAP at 5 minutes after skull pin insertion was lower than that of just before skull pin insertion (P < 0.05). In group FB, MAP at 1 and 5 minutes after skull pin insertion was lower than that of just before skull pin insertion (P < 0.05). The hemodynamic response to skull pin insertion was effectively suppressed with both methods. Still, the addition of scalp infiltration to fentanyl did not provide any additional benefit. Administering an additional dose (1 microg . kg) of fentanyl just before skull pin insertion is recommended as a simple and effective option that requires no extra time.
PURPOSE: The goals of this study were to develop a technique for creating a computerized composite skull model and to test its accuracy. The computerized composite skull model is the combination of a 3-dimensional (3D) computed tomography (CT) bone model with digital dental models. MATERIALS AND METHODS: A dry skull with intact dentition was used in development of the technique. The creation of the computerized composite skull model was divided into 3 steps. The first step was to create digital dental models. The second step was to create a 3D CT bone model of the craniomaxillofacial skeleton. The last step was to incorporate the digital dental models into the 3D CT skull model, creating a computerized composite skull model. The accuracy of the computerized composite skull model was assessed. Bone-to-bone, tooth-to-tooth, and bone-to-tooth measurements were made on the computerized composite skull model and the dry skull. Pearson correlation coefficient and linear regression tests were performed. RESULTS: A technique to create a computerized composite skull model was developed. This computerized model not only represented bony structures from CT data but also reproduced dentition from digital dental models. For the bone-to-bone measurements, the mean difference between the computerized composite skull model and the dry skull was 0.5 +/- 0.6 mm. For the tooth-to-tooth measurements, the mean difference was 0.1 +/- 0.2 mm. For the bone-to-tooth measurements, the mean difference was 0.2 +/- 0.3 mm. CONCLUSIONS: This study showed the feasibility of creating a computerized composite skull model as well as its accuracy.
OBJECT: Skull bone regeneration induced by transforming growth factor-beta1 (TGFbeta1)-containing gelatin hydrogels (TGFbeta1-hydrogels) was investigated using a rabbit skull defect model. Different strengths of TGFbeta1 were examined and compared: different TGFbeta1 doses in gelatin hydrogels with a fixed water content, different water contents in gelatin hydrogels with a fixed TGFbeta1 dose, and TGFbeta1 in solution form. In addition, regenerated skull bone was observed over long time periods after treatment. METHODS: Soft x-ray, dual energy x-ray absorptometry, and histological studies were performed to assess the time course of bone regeneration at a 6-mm-diameter skull defect in rabbits after treatment with TGFbeta1-hydrogels or other agents. The influence of TGFbeta1 dose and hydrogel water content on skull bone regeneration by TGFbeta1-hydrogels was evaluated. Gelatin hydrogels with a water content of 95 wt% that incorporated at least 0.1 microg of TGFbeta1 induced significant bone regeneration at the rabbit skull defect site 6 weeks after treatment, whereas TGFbeta1 in solution form was ineffective, regardless of dose. The in vivo degradability of the hydrogels, which varied according to water content, played an important role in skull bone regeneration induced by TGFbeta1 -hydrogels. In our hydrogel system, TGFbeta1 is released from hydrogels as a result of hydrogel degradation. When the hydrogel degrades too quickly, it does not retain TGFbeta1 or prevent ingrowth of soft tissues at the skull defect site and does not induce bone regeneration at the skull defect. It is likely that hydrogel that degrades too slowly physically impedes formation of new bone at the skull defect. Following treatment with 0.1-microg TGFbeta1-hydrogel (95 wt%), newly formed bone remained at the defect site without being resorbed 6 and 12 months later. The histological structure of the newly formed bone was similar to that of normal skull bone. Overgrowth of regenerated bone and tissue reaction were not observed after treatment with TGFbeta1 -hydrogels. CONCLUSIONS: A TGFbeta1-hydrogel with appropriate biodegradability will function not only as a release matrix for the TGFbeta1, but also as a space provider for bone regeneration. The TGFbeta1-hydrogel is a promising surgical tool for skull defect repair and skull base reconstruction.
Diffusely increased skull uptake (a hot skull) is often seen in patients with bone metastases and metabolic diseases. This finding is also, however, noticed in normal bone scans of aged women. To determine whether the hot skull could be considered a normal variant in elderly women and is associated to menopause, we studied 282 normal bone scans (166 women and 116 men without metabolic and hormonal disease; age range 11 to 84 yr). We divided the patients into eight age groups--ages 10-19, 20-29, 30-39, 40-49, 50-59, 60-69, 70-79, and 80-89 yrs. Measurements of skull uptake were obtained from anterior total body views using contrast-to-noise ratio (CNR). CNR for the skull was calculated using the following equation: (counts skull - counts femur)/square root of counts skull+counts femur, where the denominator signifies a measure of the noise and the numerator represents the contrast between the skull and the midfemur. Counts skull and femur are the number of average counts per one pixel recorded over the skull and midfemur, respectively. The sex dependent difference in skull uptake began to develop in the age group 30-39 yrs (p less than 0.05). The skull showed greater activity in women than in men for age groups from 30-39 to 80-89 yrs. In the age groups 50-59 and 60-69, the difference was particularly large (p less than 0.001).(ABSTRACT TRUNCATED AT 250 WORDS)
OBJECTIVE: The majority of paleopathological investigations focus on the study of the skull. This is because the skull is the most frequently preserved part of the human body recovered from archaeological excavations. From studying the skull, a variety of information can be obtained regarding the individual, such as sex, age, nutritional status, and other disease processes, if present. METHODS: This study represents the examination of more than 700 human skulls recovered from archaeological excavations from the Andean region of southern Peru and northern Chile and dating back more than 8000 years. RESULTS: A variety of skull abnormalities were encountered. The nonmetric variables of Huschke's foramina and palatine tori were common. Cranial deformation was observed in more than 85% of the cases. There were two cases of sagittal synostosis. Iron deficiency anemia resulting in porotic hyperostosis of the skull was evident in certain cultures. Exostoses of the external auditory canal resulting from chronic otitis was evident only among coastal populations. One skull demonstrated a periostitis consistent with Treponema infection. Trephination was encountered only in the skulls from Peru. Fifty-four cases of skull fractures were observed, half of which showed evidence of healing. Finally, only two cases of neoplastic skull lesions were encountered. CONCLUSION: The study of the human skull alone provides a large amount of information regarding the health and diseases of ancient populations.
BACKGROUND: The value of routine skull radiography as a method of predicting intracranial injury is controversial. We aimed to assess the effectiveness of skull radiography by prospectively studying head-injured children admitted to a children's hospital that serves an urban population. METHODS: Over a 2-year period, 9269 children attended our accident and emergency department with head injury, and 6011 were referred for skull radiography. All children who were admitted to hospital or had a skull fracture (n = 883) were included in the study. Computed tomography (CT) was done in children with skull fractures on radiography and in those without fractures if there were neurological indications. FINDINGS: Radiographs showed 162 fractures (2.7% of all radiographs and 18% of study group radiographs). Staff in the accident and emergency department missed 37 (23%) fractures. CT scan was done on 156 children, of whom 107 had a skull fracture. 23 children were found to have intracranial injuries on CT. The presence of neurological abnormalities had a sensitivity for identification of intracranial injury of 91% (21 of 23) and a negative predictive value of 97%. The corresponding values for skull fracture on radiography were 65% (15 of 23) and 83%. Four children died, of whom only one had a skull fracture. INTERPRETATION: In children, severe intracranial injury can occur in the absence of skull fracture. Skull radiography is not a reliable predictor of intracranial injury and is indicated only to confirm or exclude a suspected depressed fracture or penetrating injury, and when non-accidental injury is suspected, including in all infants younger than 2 years. Clinical neurological abnormalities are a reliable predictor of intracranial injury. If imaging is required, it should be with CT and not skull radiography.
OBJECTIVE: The aim of this study was to demonstrate computed tomography (CT) features of maxillofacial tumors invading the central skull base and to offer information in aiding diagnosis. METHODS: Fifty-eight maxillofacial tumors with central skull base invasion shown on axial and coronal CT images were divided into benign (13 cases) and malignant (45 cases) groups, based on their pathologic outcomes as proven by biopsy and surgery. RESULTS: Four manifestations of the skull base abnormality were observed on CT images: (1) resorption of central skull base (53 cases, 11 benign and 42 malignant tumors); (2) enlargement of the foramen and canal in the central skull base (20 cases, 4 benign and 16 malignant tumors); (3) thinning of the central skull base (11 cases, 8 benign and 3 malignant tumors); and (4) displacement of the central skull base (5 cases, all benign tumors). The following structures of the central skull base were involved: the roof of the pterygoid process of the sphenoid bone (49 cases), the sphenoid greater wing (37 cases), the sphenoid body and sinus (33 cases), the petrous apex (12 cases), the clivus (4 cases), and the articular surface of the temporal squama (3 cases). Of 58 patients, 30 (7 benign and 23 malignant) had tumors with central skull base erosion that infiltrated into the cranial cavity. CONCLUSION: Benign maxillofacial tumors with center skull base erosion tended to lead to the displacement and thinning of the base of the middle skull fossa in contrast with tumors with malignant maxillofacial tumors. It is believed that these CT manifestations might be valuable in making a differential diagnosis.
OBJECTIVE: To provide clinical evidence to support the age dependent relationship between facial fractures and skull fractures. DESIGN: Retrospective chart review of all children and adults admitted with combined facial fractures and skull fractures and skull fractures alone between January 1991 and November 1997. SETTING: The Albany Medical Center Hospital, a tertiary level-one trauma center. PATIENTS: Two hundred and one children, ages 1 month to 17 years, with skull fractures (frontal, parietal, or temporal), and 41 children with concurrent facial fractures were included in this study. One hundred and thirty-nine adults, ages 18-90 years, with skull fractures, and 70 adults with concurrent facial fractures were also studied. OUTCOME MEASURES: The gender, age, skull fracture, facial fracture, Glasgow coma score (GCS), mechanism of injury, and outcome of all patients admitted with frontal, parietal, or temporal fractures with or without facial fractures. RESULTS: There are a significantly greater (P < 0.001) number of facial fractures associated with skull fractures among adults as compared to children. Moreover, there is an exponential rise in facial fractures associated with skull fractures between infancy and adolescence. The GCS of children with combined facial and skull fractures is significantly lower than in those with skull fractures only (P < 0.001). CONCLUSION: The spectrum of craniofacial injuries is related to the specific developmental stage of the craniofacial skeleton. This is demonstrated by the variable pattern of combined facial and skull fractures observed clinically in children and adults.
Rigid immobilization of the cervical spine in children is normally accomplished with a halo ring attached to the skull with pins. Concern exists about the risk of halo pin complications in small children due to their diminished skull thickness. More data are needed on biomechanical properties of the immature skull and on safe levels for halo pin penetration forces. The study included halo pin penetration tests on 43 skull samples obtained from eight fetal calves, radial compression tests of 11 skull samples, and histology. Compressive composite elastic modulus (15-139MPa), yield stress (1-5MPa) and composite consolidation modulus (188-479MPa) were measured in the skull's radial direction. Pin penetration force (F) in Newtons at a pin-penetration depth equal to the original skull thickness (T) in mm, was related to T as: F=100+4.3e(T) (R(2)=0.76, p<0.0001). However, the 95% confidence limits on individual predictions were wide, e.g., 0-475MPa for T=1.5mm and 0-700MPa for T=4mm. These results suggest that skull thickness cannot be reliably used to predict halo pin penetration loads in a skull with similar structural and mechanical properties to that of the fetal calf. Due to the lack of available human data for comparison, the relevance of using the fetal calf skull as a model for human infants and young children remains inconclusive. Clinical recommendations regarding pediatric halo pin penetration loads cannot be made without further study of children's skull structure and biomechanical properties.
PURPOSE: To measure the degree of attenuation of radiation dose by the skull base bone in patients with nasopharyngeal carcinoma (NPC) and to study its clinical importance. MATERIALS AND METHODS: Isodose distribution in 11 patients with NPC who received bilaterally opposed large-field irradiation (1.8 Gy per fraction) was studied with a three-dimensional treatment planning system with tissue inhomogeneity correction. Also studied were the sites of local tumor recurrence in 37 patients with NPC and skull base destruction (>/=0.5 cm) or intracranial invasion treated with radiation therapy from January 1989 to December 1992. Regression analyses were performed. RESULTS: In the dosimetric study, the low-dose areas (<1.65 Gy) were located at the level of the skull base in all 11 patients. A significantly positive correlation between the maximum width of the skull base bone and the low-dose volume (<1.65 Gy) was demonstrated (P =.003, linear regression). In the clinical study, local tumor recurrence was noted in 18 patients (49%). The sites of local recurrence included skull base in 16 patients (43%) and nasopharynx in six patients (16%). Wider skull base bone was a significant predictor of skull base recurrence after radiation therapy (P =.03, logistic regression). CONCLUSION: Herein demonstrated is the inadequacy of the radiation dose over the skull base due to attenuation by the skull base bone. The relationship between width of skull base bone and skull base tumor recurrence also is established.
Every craniotomy requires immediate replacement of a fresh autograft of skull or, in the presence of cerebral swelling, delayed reimplantation of preserved autogenous skull. Resumption of osteogenesis, the index of viability, determines the effectiveness of these segments of calvaria in protecting the brain and restoring skull conformity. The cellular response in skull replaced either at the end of craniotomy or after frozen preservation was studied by light and fluorescence microscopy, skull roentgenograms, and radionuclide scintigraphy. In 5 patients eventual total remodeling of skull was found at the time of a second craniotomy performed from 1 to 19 years after the first. In 12 patients skull sections removed aseptically at craniotomy were frozen and stored for 1 to 35 months at -20 degrees C in bacitracin. This cytotoxic preservative method fixed the tissue, which appeared unchanged on light microscopy and was sterile on bacteriological and fungal cultures. In 53 patients who underwent autogenous cranioplasty with skull stored frozen for 3 weeks to 19 months, 48 operations were totally successful. Complications included infections in 2 patients, resorption in 2 infants, and incomplete restoration in 1 adult. In 10 patients the sequential dynamics of skull revitalization were found to be: revascularization, resorption, and accretion. The repair of membranous skull is similar to that of endochondral bone of the skeleton. Skull is metabolically intensely active after reimplantation and is the ideal material for cranioplasty.
INTRODUCTION: On available anthropological material of seven skulls that dates back to the 3800 B.P. to the 2000 B.P., taken from various archaeological sites of Xinjiang area in China, the racial characteristics were studied. The investigated skulls are part of the collection of the prehistoric skeletons housed at the Institute of Archaeology in Beijing. METHOD: Anthropological examination comprised measuring of 32 cranial diameters and calculation of 18 cranial indices, and morphological analyses of 26 traits of the skull and 36 epigenetic characteristics. RESULTS: Three skulls were excavated in Hejing cemetery dated in 1800 years B.P. The skulls are mesocranic, acrocranic and metriocranic (Tab. 1) with outstanding occipital tori and flattening in the lambdoid region (Tab. 2). The orbits are quadrangular, glabella is small with sharp supraorbital margin, the palate is narrow, the mandible is gracile. The fourth skull was excavated in Alagou cemetery from about 2700-2000 years B.P. The skull also possesses western racial characteristics similar to the East Mediterranean type. The fifth skull is from Zhaosu cemetery dated in about 2400-1800 years B.P. The skull is mesocranic with the high cranial vault, broad forehead and quadrangular orbits. The sixth and seventh skulls belonged to the Pfoto-European type. They are excavated in the Gumogou cemetery (about 3800 years B.P.) and in Quinghai region. Among the studied skulls there was no case showing Mongoloid characteristics. Data concerning the epigenetic characteristics (Tab. 3) suggest differences in frequency of certain traits (Os Japonicum, torus palatinus, processus paracondylaris, foramen spinosum bridging) found in investigated material in comparison with findings in other European populations. DISCUSSION: On the basis of the obtained results and investigations of Chinese scientists, it can be concluded that Western racial elements with primitive morphological characteristics had entered from Central Asia into Xinjiang area at least by the early Bronze Age. Other racial elements close to that of the East Mediterranean entered into the western part of Xinjiang several centuries B.C.E. Mongoloid racial elements have not been found in our material. Only about 10 percent among 274 crania investigated by Chinese anthropologists were described as Mongoloid in morphology. The late emergence of the East Mongoloid population, about 300 years B.P. that appeared in small groups, contributes to the conclusion that eastward movement of the Western race to Xinjiang was more rapid than the westward movement of Mongoloid people in that period.
Pneumatization and morphogenesis of the temporal mastoid process take place concurrently and exhibit noticeable variability. The mastoid process is phylogenetically the youngest part of the skull. The aim of this work was to examine the pneumatization of the mastoid process in mediaeval and contemporary skulls using radiological and anthropometric methods. 85 male skulls from the second half of the 20th century were compared with 102 male and 50 female skulls from the Middle Ages. Bilateral X-ray images of mastoid processes according to Schuller were obtained and anthropometric measurements were done. Planimetry was used to obtain the air cell area of the mastoid processes. Correlations between several parameters of the temporal bone, facial bones, cranial bones and pneumatization of the mastoid process were studied. X-ray images revealed four types of the mastoid process: pneumatic, mixed, sclerotic, and apneumatic. The pneumatic mastoid process prevailed in every group of skulls. The mixed type was the least frequent in mediaeval female skulls and most frequent in contemporary male skulls. The apneumatic type was the rarest one in all groups of skulls. The largest surface area of mastoid air cell system was found in contemporary male and the smallest in mediaeval female skulls (Fig. 5). An asymmetry between left and right processes was observed in mediaeval and contemporary skulls, being more evident in the latter. No correlation was found between anthropometric parameters of the skull and the extent of pneumatization of the mastoid process.
Foramen Vesalius is known to be an inconstant foramen, which appears in the anteriomedial side of the foramen ovale. The foramen Vesalius is classified into the open type and the closed type. We studied the frequencies and the types of foramen Vesalius in Japanese by examining 20 juvenile skulls from 3 months to 8 years old and 400 adult skulls from 18 to 91 years old. Of the 20 juvenile skulls, 11 skulls (55.00%) had foramen Vesalius. Of the 400 adult skulls, 87 skulls (21.75%) had foramen Vesalius; 69 (21.50%) in 321 male and 18 (22.78%) in 79 female skulls. No remarkable differences were observed in the ratio between the male and the female, and between the left side and the right side. Among the 69 adult male skulls, the foramen Vesalius was bilateral in 52 skulls (75.36%) and unilateral in 17 (24.64%); among the 18 adult female skulls, it was bilateral in 13 (72.22%) and unilateral in 5 (27.78%). The ratio of the closed type was slightly higher than that of the open type in both sexes and in both sides; however, no remarkable differences were observed. The skulls with one foramen Vesalius were most frequent; those with two followed it and those with 3 foramen Vesalius were least frequent. No remarkable differences were observed in the number of foramen Vesalius between the sexes and the sides.
OBJECTIVE: To evaluate the role of bone SPECT in diagnosing metastasis to the skull base in cancer patients. BACKGROUND: Skull base metastasis often causes characteristic clinical syndromes. Antitumor treatment ameliorates or stabilizes symptoms in most patients. Diagnosis may be difficult when neuroimaging studies are negative (as occurs in about one-quarter of patients). Case reports have suggested a role for bone SPECT in these patients. METHODS: We reviewed the charts of all patients (1993-1996) at our institution who had skull base SPECT and at least one neuroimaging study (CT or MRI) for clinically suspected metastasis to the base of the skull. Bone SPECT, CT, and MRI were blindly re-evaluated. RESULTS: We studied 56 patients, of whom 36 had skull base metastasis. Twenty patients had other causes of the clinical syndrome, including leptomeningeal and posterior fossa metastasis, or benign causes. In 29 of 36 patients (81%) with skull base metastasis, CT or MRI clearly demonstrated the lesion. Bone SPECT identified a hot spot in the appropriate region of the skull base in 28 of 36 patients (78%). All seven patients with negative CT or MRI had positive SPECT and four of these had a response to anti-tumor treatment. CONCLUSIONS: SPECT of the skull base can demonstrate lesions not identifiable by CT or MRI. In cancer patients suspected of having skull base metastasis, we recommend SPECT of the skull base when CT or MRI studies are negative.