986 resultados para SKULL BASE SURGERY


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Introduction: Perineural invasion is a well-recognized form of cancer dissemination. However, it has been reported only in few papers concerning cutaneous carcinomas ( basal cell, BCC, and squamous cell, SCC). Moreover, the incidence is considered to be very low. Niazi and Lambert [Br J Plast Surg 1993; 46: 156-157] reported only 0.18% of perineural invasion among 3,355 BCCs. It is associated with high-risk subtypes, as morphea-like, as well as with an increased risk of local recurrence. No paper was found in the literature looking for perineural invasion in very aggressive skin cancers with skull base extension, with immunohistochemical analysis. Methods: This is a retrospective review, including 35 very advanced skin carcinomas with skull base invasion (24 BCCs and 11 SCCs, operated on at a single institution from 1982 to 2000). Representative slides were immunohistochemically evaluated with antiprotein S-100, in order to enhance nerve fibers and to detect perineural invasion. The results were compared to 34 controls with tumors with a good outcome, treated in the same time frame at the same Institution. Results: Twelve (50.0%) of the BCCs with skull base invasion had proven perineural invasion, as opposed to only 1 (4.6%) of the controls, and this difference was statistically significant (p < 0.001). Regarding SCCs, 7 aggressive tumors (63.6%) showed perineural invasion compared to only 1 (10.0%) of the controls, but this difference did not reach significance (p=0.08), due to the small number of cases. Conclusions: In this series, it was demonstrated that immunohistochemically detected perineural invasion was very prevalent in advanced skin carcinomas. In addition, it was statistically associated with extremely aggressive BCCs with skull base invasion. Copyright (c) 2008 S. Karger AG, Basel

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Maxillary basal bone, dentoalveolar, and dental changes in Class II Division 1 patients treated to normal occlusion by using cervical headgear and edgewise appliances were retrospectively evaluated. A sample of 45 treated patients was compared with a group of 30 untreated patients. Subjects were drawn from the Department of Orthodontics, Araraquara School of Dentistry, Brazil, and ranged in age from 7.5 to 13.5 years. The groups were matched based on age, gender, and malocclusion. Roughly 87% of the treated group had a mesocephalic or brachicephalic pattern, and 13% had a dolicocephalic pattern. Cervical headgear was used until a Class I dental relationship was achieved. Our results demonstrated that the malocclusions were probably corrected by maintaining the maxillary first molars in position during maxillary growth. Maxillary basal bone changes (excluding dentoalveolar changes) did not differ significantly between the treated and the untreated groups. Molar extrusion after the use of cervical headgear was not supported by our data, and this must be considered in the treatment plan of patients who present similar facial types. (Am J Orthod Dentofacial Orthop 2001;119:531-9).

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The prototyping is a method for reconstruction of human body segments by computer software. It has been used in neurosurgery for cranial reproduction in patients allowing the programming of surgical procedures and the production of prosthesis to reconstruct bone failures in the skull. We present two cases of cranioplasty performed with the use of acrylic prosthesis constructed by prototyping. After 10 months of follow-up, they donot present signs of infection and show good aesthetic result. The advantages pointed at the literature for this method (reduction of surgical time, easy technical handle, and good aesthetic result) were confirmed.

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This study gathered some of the most relevant researches already undertaken regarding the Temporomandibular Joint, presenting descriptions of its anatomy and dynamics, and relating them to the main aspects of joint dysfunctions. Literature recognizes that the Temporomandibular Joint, responsible for lower jaw movements, comprehends the skull base and the jaw bone. Its anatomy and dynamics are of great importance in order to understand the functions of Stomatognathic System as well as to study Temporomandibular Joint Dysfunction. The elements that compose this synovial joint and the bilateral characteristic confer eminent importance to the ATM before the skeleton head, the ability to perform broad movements and high complexity in its operation. It is accepted that the overload of one anatomical structure from the TMJ or other components of the Stomatognathic System leads to Temporomandibular Joint Dysfunctions. These disorders have different etiologies, ranging from malocclusion to emotional stress, and various forms of treatment, which are related in this study

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The hypoglossal nerve (HN) is responsible for the intrinsic and extrinsic muscles of the tongue. Knowledge of this is extremely important because this nerve is responsible for tongue movement. HN paralysis can be associated to the disease itself in various zones in which the NH travels, mainly the hypoglossal canal (HC). Variations in shape of the hypoglossal canal have been pointed to as the cause of HN paralysis in several studies. Four hundred dried intact human skulls without sex or race identification, belonging to the Discipline of Anatomy of ICTSJC – UNESP were studied. Each canal was classified into types: type I (without division in the HC), type II (HC with low bone spike), type III (HC more than two projections bone), type IV (presence of complete bony bridge without dividing HC into two distinct canals) and type V (presence of bone bridge by dividing into two HC canals). HC was found in 100% of skulls studied in both side. Regarding types, we found 538 (67.25%) hypoglossal canal of type I (34%, right side and 33.25%, left side), 108 (13.5%) of type II (7.38%, right side, and 6.13%, left side), 60 (7.5%) hypoglossal canal of type III (3.5%, right side and 4.0%, left side) 84 (10.5%) of type IV (4.75%, right side and 5.75%, left side) and 5 (0.63%) of the type V (0.13%, right side and 0.5%, left side). We found 5 (0,63%) different HC and classified ourselves in type VI, VII and VIII. The average angle was 51,3º on right side and 50,25º on left side. Detailed knowledge of the anatomy of the CH supports professionals in interventions of bloody skull base and also in giving the correct diagnosis of the probable causes of paralysis of the hypoglossal nerve

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In this study, it is proposed to evaluate the anteroposterior position of mandible in children with Angle Class II, division 1 malocclusions, to compare two different methods of evaluating the jaw position and verifying the correlation between these two methods. We selected 26 Brazilian children with vertical growth pattern and Angle Class II, division 1 malocclusions, aged between 7 years and 8 months to 9 years and 6 months. The evaluation of the anteroposterior position of the mandible was performed with the use of lateral cephalograms by cephalometric angular SNB and linear Pog-Nperp. Based on the results obtained, it was concluded that the SNB identified more children with mandibular retrusion than Pog-Nperp; the increased tip of the SN plane may have decreased values of SNB; Pog-Nperp minimizes the possibility of error in the anteroposterior position of the mandible, since it eliminates the variable tip of the anterior skull base (SN plane); none of the cephalometric measurements used are able to eliminate the influence of the nasion point in the anterior-posterior and vertical position; correlation between SNB and Pog-Nperp is very low.

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Objectives/Hypothesis: Demonstrate the endoscopic anatomy of the palatovaginal (PV) canal and artery for identification and dissection of the vidian nerve during endoscopic transpterygoid approaches. Evaluate the length of the PV canal and its relation with the vidian nerve. Show that the traditionally known PV canal is a misnomer and should be renamed. Study Design: Experimental study: anatomical and radiological. Methods: Dissection of eight cadaveric heads was performed to demonstrate the endoscopic anatomy of the PV canal. Computed tomography scan analysis of 20 patients was used to evaluate the length of the PV canal, the angle formed between this canal and the vidian nerve, and the distance between the vidian canal and the PV canal. Study of 10 dry skull bases was performed to verify the structures involved in the formation of the PV canal. Results: Anatomic steps and foundations for dissection of the vidian nerve using the PV canal as a landmark were described. The mean length of the PV canal was 7.15 mm. The mean proximal distance between the vidian and the PV canal was 1.95 mm, and the mean distal distance was 4.14 mm. The mean angle between those canals was 48 degrees. The osteology study showed the vaginal process of the sphenoid bone did not contribute to the formation of the PV canal. Conclusions: Our anatomic investigations, radiologic studies, and surgical experience demonstrate the important anatomic relationship of the PV canal with the vidian canal and the relevance of the PV canal as a surgical landmark in endoscopic endonasal transpterygoid approaches. Anatomically, PV canal is a misnomer and should be replaced with palatosphenoidal canal.

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Form und Gestalt kraniofazialer Strukturen sind primär beeinflusst durch die inhärente Integration der unterschiedlichsten Funktionssysteme und externer selektiver Einflüsse. Die Variabilität der Schädel-Morphe ist ein Indikator für solche Einflussfaktoren und damit ein idealer Gegenstand für vergleichende Analysen morphogenetischer Formbildung. Zur Ermittlung morphologisch-adaptiver Trends und Muster wurden sowohl Hypothesen zur morphologischen Differenziertheit als auch zu Korrelationen zwischen modularen Schädelkompartimenten (fazial, neurokranial, basikranial) untersucht. Zusätzlich wurden aus Schichtröntgenaufnahmen (CT) virtuelle Modelle rekonstruiert, welche die Interpretation der statistischen Befunde unterstützen sollten. Zur Berechnung der Gestaltunterschiede wurden mittels eines mechanischen Gelenkarm-Messgerätes (MicroScribe-G2) max. 85 ektokraniale Messpunkte (Landmarks) bzw. dreidimensionale Koordinaten an ca. 520 Schädeln von fünf rezenten Gattungen der Überfamilie Hominoidea (Hylobates, Pongo, Gorilla, Pan und Homo) akquiriert. Aus dem Datensatz wurden geometrische Störfaktoren (Größe, Translation, Rotation) mathematisch eliminiert und die verbleibenden Residuale bzw. ‚Gestalt-Variablen‘ diversen multivariat-statistischen Verfahren unterzogen (Faktoren, Cluster-, Regressions- und Korrelationsanalysen sowie statistische Tests). Die angewandten Methoden erhalten die geometrische Information der Untersuchungsobjekte über alle Analyseschritte hinweg und werden unter der Bezeichnung „Geometric Morphometrics (GMM)“ als aktueller Ansatz der Morphometrie zusammengefasst. Für die unterschiedlichen Fragestellungen wurden spezifische Datensätze generiert. Es konnten diverse morphologische Trends und adaptive Muster mit Hilfe der Synthese statistischer Methoden und computer-basierter Rekonstruktionen aus den generierten Datensätzen ermittelt werden. Außerdem war es möglich, präzise zu rekonstruieren, welche kranialen Strukturen innerhalb der Stichprobe miteinander wechselwirken, einzigartige Variabilitäten repräsentieren oder eher homogen gestaltet sind. Die vorliegenden Befunde lassen erkennen, dass Fazial- und Neurokranium am stärksten miteinander korrelieren, während das Basikranium geringe Abhängigkeiten in Bezug auf Gesichts- oder Hirnschädelveränderungen zeigte. Das Basikranium erweist sich zudem bei den nicht-menschlichen Hominoidea und über alle Analysen hinweg als konservative und evolutiv-persistente Struktur mit dem geringsten Veränderungs-Potential. Juvenile Individuen zeigen eine hohe Affinität zueinander und zu Formen mit einem kleinem Gesichts- und großem Hirnschädel. Während das Kranium des rezenten Menschen primär von Enkephalisation und fazialer Retraktion (Orthognathisierung) dominiert ist und somit eine einzigartige Gestalt aufweist, zeigt sich der Kauapparat als maßgeblich formbildendes Kompartiment bei den nicht-menschlichen Formen. Die Verbindung von GMM mit den interaktiven Möglichkeiten computergenerierter Modelle erwies sich als valides Werkzeug zur Erfassung der aufgeworfenen Fragestellungen. Die Interpretation der Befunde ist durch massive Interkorrelationen der untersuchten Strukturen und der statistisch-mathematischen Prozeduren als hoch komplex zu kennzeichnen. Die Studie präsentiert einen innovativen Ansatz der modernen Morphometrie, welcher für zukünftige Untersuchungen im Bereich der kraniofazialen Gestaltanalyse ausgebaut werden könnte. Dabei verspricht die Verknüpfung mit ‚klassischen’ und modernen Zugängen (z. B. Molekularbiologie) gesteigerte Erkenntnismöglichkeiten für künftige morphometrische Fragestellungen.

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We describe the multidisciplinary findings in a pre-Columbian mummy head from Southern Peru (Cahuachi, Nazca civilisation, radiocarbon dating between 120 and 750 AD) of a mature male individual (40-60 years) with the first two vertebrae attached in pathological position. Accordingly, the atlanto-axial transition (C1/C2) was significantly rotated and dislocated at 38° angle associated with a bulging brownish mass that considerably reduced the spinal canal by circa 60%. Using surface microscopy, endoscopy, high-resolution multi-slice computer tomography, paleohistology and immunohistochemistry, we identified an extensive epidural hematoma of the upper cervical spinal canal-extending into the skull cavity-obviously due to a rupture of the left vertebral artery at its transition between atlas and skull base. There were no signs of fractures of the skull or vertebrae. Histological and immunohistochemical examinations clearly identified dura, brain residues and densely packed corpuscular elements that proved to represent fresh epidural hematoma. Subsequent biochemical analysis provided no evidence for pre-mortal cocaine consumption. Stable isotope analysis, however, revealed significant and repeated changes in the nutrition during his last 9 months, suggesting high mobility. Finally, the significant narrowing of the rotational atlanto-axial dislocation and the epidural hematoma probably caused compression of the spinal cord and the medulla oblongata with subsequent respiratory arrest. In conclusion, we suggest that the man died within a short period of time (probably few minutes) in an upright position with the head rotated rapidly to the right side. In paleopathologic literature, trauma to the upper cervical spine has as yet only very rarely been described, and dislocation of the vertebral bodies has not been presented.

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This retrospective study describes the clinical and magnetic resonance (MR) imaging features of chronic orbital inflammation with intracranial extension in four dogs (two Dachshunds, one Labrador, one Swiss Mountain). Intracranial extension was observed through the optic canal (n=1), the orbital fissure (n=4), and the alar canal (n=1). On T1-weighted images structures within the affected skull foramina could not be clearly differentiated, but were all collectively isointense to hypointense compared with the contralateral, unaffected side, or compared with gray matter. On T2-, short tau inversion recovery (STIR)-, or fluid-attenuated inversion recovery (FLAIR)-weighted images structures within the affected skull foramina appeared hyperintense compared with gray matter, and extended with increased signal into the rostral cranial fossa (n=1) and middle cranial fossa (n=4). Contrast enhancement at the level of the affected skul foramina as well as at the skull base in continuity with the orbital fissure was observed in all patients. Brain edema or definite meningeal enhancement could not be observed, but a close anatomic relationship of the abnormal tissue to the cavernous sinus was seen in two patients. Diagnosis was confirmed in three dogs (one cytology, two biopsy, one necropsy) and was presumptive in one based on clinical improvement after treatment. This study is limited by its small sample size, but provides evidence for a potential risk of intracranial extension of chronic orbital inflammation. This condition can be identified best by abnormal signal increase at the orbital fissure on transverse T2-weighted images, on dorsal STIR images, or on postcontrast transverse or dorsal images.

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The treatment of complex cerebrovascular or skull base pathological conditions necessitates a microsurgical blood flow preservation or augmentative revascularization procedure as either an adjunctive safety measure or a definitive treatment. The brain is susceptible to ischemia, and procedure-related risks can be minimized by the reduction of occlusion time or the use of a nonocclusive technique. The authors therefore analyzed the feasibility of an automatic device (C-Port xA, Cardica) designed for constructing an end-to-side anastomosis with or without flow interruption for a middle cerebral artery (MCA) bypass in a human cadaveric model and in an in vivo craniotomy simulation model.

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Malignant otitis externa (MOE) is an aggressive but benign entity which evolves into skull base osteomyelitis. An 81-year-old female patient was admitted for left hemiparesis and homonymous hemianopia. She complained of headache radiating to the right cervical area. A recent history of recurrent otitis media was present. Head and neck imaging showed an ischemic infarction (right temporo-occipital) and a parapharyngeal soft tissue mass originating in an external and medial ear infection. Culture samples revealed Pseudomonas aeruginosa infection leading to the diagnosis of Malignant otitis externa (MOE). Parenteral antibacterial therapy and hyperbaric oxygen therapy resulted in improvement.

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"From the Smithsonian report for 1957."