Transverse development of the craniofacial skeleton and dentition between 7 and 15 years of age--a longitudinal postero-anterior cephalometric study.
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The aim of this study was to identify the transverse growth pattern of the craniofacial skeleton and dentition from 7 to 15 years of age. The database for this longitudinal study comprised the postero-anterior (PA) cephalograms and dental casts at 7, 9, 11, 13 and 15 years of age of 18 untreated Class I subjects with good occlusion from the Belfast Growth Study. Differential magnification of the PA cephalograms was corrected using the method of similar triangles. Most of the craniofacial widths were larger in males than in females. At 15 years of age, the gender differences in craniofacial widths were more pronounced than at 7 years of age. The majority of the skeletal dimensions showed a progressive increase in width. In contrast, there was a deceleration in the increase in maxillary and mandibular intermolar widths after 11 years of age in males and even a slight decrease in the intermolar width beyond 11 years of age in females. Growth curves were calculated where the values of the respective variables were expressed in terms of percentage of attainment at 7, 9, 11 and 13 years of age when compared with 15 years of age. For mid-facial, bizygomatic and skeletal maxillo-mandibular widths, percentile attainments in the range of 84-91 per cent indicated a greater remaining growth potential at 7 years of age than for the cranial width where growth was almost complete. By the age of 7 years, over 95 per cent of the growth in the intermolar width had occurred. (+info)
The relationship between presbycusis and mastoid pneumatization.
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Presbycusis is defined as the natural hearing loss accompanying aging, caused by degenerative changes in the inner ear. The etiology of presbycusis is uncertain. However, it would appear that a complex genetic cause is most likely. The determinants of mastoid size continue to be controversial. One of the pneumatization theories is the hereditary theory. In this study, the possible relationship between presbycusis and the extent of mastoid pneumatization was investigated. This study was carried out on 21 patients with presbycusis and 21 normal subjects of similar ages. The pneumatized volume was measured by computerized tomography. The temporal bone was scanned at 2 mm thickness intervals. Exposure (kV 130, mA105). The scan plane was parallel to the orbitomeatal line and the CT images covered the entire mastoid region. The average mastoid pneumatization in presbycusis group was 6.08 +/- 2.52 cm(3) in the right ear and 6.19 +/- 2.93 cm(3) in the left ear. However, in the control group it was 4.69 +/- 3.17 cm(3) in the right ear (p=0.12) and 5.10 +/- 3.49 cm(3) in the left ear (p=0.28). No significant difference was found between the presbycusis patients and normal subjects in terms of the volume of mastoid pneumatization. (+info)
Stereo morphology of temporal bone and ear.
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BACKGROUND: The temporal bone has the most complicated anatomic feature among the whole human body, which always challenges otolaryngologists. This study was to study three-dimensional (3D) morphology of the temporal bone and the ear by means of a computer image processing technique, for the purpose of providing a 3D image to help in pathological, diagnostic and surgical procedures. METHODS: Forty sets of temporal bone celloidin serial sections with reference points were prepared and the contours of selected structures and reference points were entered into a graphics programme. The technique of computer-aided 3D reconstruction was applied to obtain 3D images and parameters of the temporal bones and the ears. Stereo views of the ossicles (n = 5), the facial nerves (n = 11), the posterior tympanic sinuses (n = 11), the posterior ampullary nerves (n = 4), the endolymphatic ducts and sacs (n = 5), and the bony and membranous labyrinth (n = 1) were reconstructed. RESULTS: Three-dimensional images, including the cochlea, the ossicles, the nerves, the tendons and the endolymphatic fluid system in the temporal bone, were obtained. Stereo picture pairs and 3D parameters of spatial dimensions, angle and volume for these reconstructed structures were calculated. The arrangement of the ossicles, spatial relationship of the bony and membranous labyrinth, the whole course of the facial nerves, the endolymphatic sac and posterior tympanic cavity were clearly observable. Stereo picture pairs made the spatial relationships among the above-mentioned structures much clearer. The operation of the posterior ampullary nerve transection was designed and simulated on the graphic computer based on 3D anatomic investigations. CONCLUSION: The technique of computer-aided 3D reconstruction provides a new tool to observe the morphology of the temporal bone and thus may allow design and study of new surgical approaches. (+info)
Osteogenesis imperfecta of the temporal bone: CT and MR imaging in Van der Hoeve-de Kleyn syndrome.
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We report the progressive otic capsule demineralization around the membranous labyrinth and facial nerve in an adult patient with osteogenesis imperfecta tarda. Whereas the initial CT scan showed bandlike, undermineralized pericochlear areas, 2 years later, repeat CT performed because of hearing deterioration showed progression of these findings to the promontory, the round window niche, and the labyrinthine and tympanic segments of the facial nerve canal. MR imaging demonstrated enhancement of the abnormal otic capsule and of the intratemporal and canalicular facial nerve. The differential diagnosis of osteogenesis imperfecta tarda affecting the temporal bone includes otosclerosis, Paget disease, otosyphilis, and Camurati-Engelmann disease. (+info)
Small mid-Pleistocene hominin associated with East African Acheulean technology.
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Hominin fossils from the African mid-Pleistocene are rare despite abundant Acheulean tools in Africa and apparently African-derived hominins in Eurasia between 1.0 and 0.5 million years ago (Ma). Here we describe an African fossil cranium constrained by 40Ar/39Ar analyses, magnetostratigraphy, and sedimentary features to 0.97 to 0.90 Ma, and stratigraphically associated with Acheulean handaxes. Although the cranium represents possibly the smallest adult or near-adult known between 1.7 and 0.5 Ma, it retains features observed in larger Homo erectus individuals, yet shows a distinct suite of traits indicative of wide population variation in the hominins of this period. (+info)
A procolophonoid reptile with temporal fenestration from the Middle Triassic of Brazil.
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The small tetrapod Candelaria barbouri, from the Middle Triassic of southern Brazil, is the first example of an owenettid procolophonoid outside Africa and Madagascar. Candelaria barbouri was originally described as a primitive procolophonid; however, a re-examination of the holotype, as well as new material, reveals that C. barbouri is in fact the youngest member of the Owenettidae, extending the chronological range of the group by more than 10 million years. The recognition of C. barbouri as an owenettid points to a broader diversity and distribution for owenettids than hitherto thought. In addition, C. barbouri is the first member of the Owenettidae to exhibit temporal fenestrae, a discovery that draws attention to the significance of this feature in 'anapsid' reptiles. (+info)
Efficacy of endovascular surgery for the treatment of acute epidural hematomas.
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BACKGROUND AND PURPOSE: Recent advances in the equipment and technology for endovascular surgery have led to an increasing number of patients undergoing this procedure to treat various lesions. The purpose of this study was to investigate the efficacy of early-stage endovascular surgery to treat growing acute epidural hematomas (AEDHs). METHODS: Over a period of 2.5 years, endovascular intervention was performed in nine patients with AEDHs, as shown by the extravasation of contrast medium and the recognition of growing hematomas on CT scans. Embolization was performed by using catheters superselectively advanced with a microguidewire until it reached the area just before the bleeding point. RESULTS: In all nine cases, bleeding from the middle meningeal artery ceased immediately after treatment, and further surgical intervention was avoided. In three of five patients with additional lesions, surgical intervention was also conducted to treat an acute subdural hematoma (two patients) or a contusion hematoma (one patient); in two cases, these lesions were located on the contralateral side. CONCLUSION: In patients with thin AEDHs in the early stage, angiography followed by endovascular intervention allows for conservative treatment. Notable clinical benefits can be achieved in patients with complicated, multiple lesions. (+info)
Temporal bone involvement in cherubism: case report.
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Cherubism is a rare benign hereditary fibro-osseous disease involving the mandible and maxilla. We report a case of cherubism in a 10-year-old girl for which the panoramic radiograph was insufficient for diagnosis of the disease. Clinical, histological, and radiological findings were discussed. The CT was taken and it confirmed not only the involvement of the jaws but also of the temporal bone. This was not found in the conventional radiograph. (+info)