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1.
Head Face Med ; 16(1): 3, 2020 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-32127030

RESUMO

BACKGROUND: The reconstruction of large head and face missing structures in the craniofacial region in children is very challenging for plastic surgeons. Expanded local and expanded axial-pattern flaps are widely used for the reconstruction of large-area scars. Free flaps are used very cautiously in children. 3D printing technology is a new technology with great development potential. 3D printing technology is used to assist in individualizing titanium alloy restorations for prefabricated skull defect repair. This application has great advantages in the repair of large skull loss. However, it is crucial to choose appropriate techniques and treat deformities of the head and face with integrated approaches and collaboration among multiple departments. CASE PRESENTATION: This study proposes a method to combine the expanded flap method and 3D printing technology to achieve natural remodeling of the craniofacial region in a child. CONCLUSION: Large area of head and face missing structures can be reconstructed by using expanded skin flaps combined with 3D printing, and patients can get better new faces.


Assuntos
Anormalidades Craniofaciais , Retalhos de Tecido Biológico , Procedimentos Cirúrgicos Reconstrutivos , Criança , Anormalidades Craniofaciais/cirurgia , Cabeça , Humanos , Impressão Tridimensional , Crânio
5.
Sud Med Ekspert ; 63(1): 56-60, 2020.
Artigo em Russo | MEDLINE | ID: mdl-32040090

RESUMO

Two current approaches to the ergometric evaluation of the impact strength that lead to skull fracture are described. Within each of them, the features of particular techniques, typical expert errors, ways and means of preventing them are analyzed. Quantitative data on the contribution of various initial parameters (fracture type, age, bone thickness, skull radius of curvature, body weight, height, etc.) to the result of computational diagnostics are presented.


Assuntos
Fraturas Cranianas/diagnóstico , Fenômenos Biomecânicos , Medicina Legal , Humanos , Crânio , Fraturas Cranianas/patologia
6.
Braz Oral Res ; 34: e007, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049108

RESUMO

The aim of this study was to assess the influence of cyclosporine administration on the repair of critical-sized calvaria defects (CSDs) in rat calvaria filled with diverse biomaterials. Sixty animals were divided into two groups: the control (CTR) group (saline solution) and the cyclosporine (CCP) group (cyclosporine, 10 mg/kg/day). These medications were administered daily by gavage, beginning 15 days before the surgical procedure and lasting until the day the animals were euthanized. A CSD (5 mm Ø) was made in the calvaria of each animal, which was allocated to one of 3 subgroups, according to the biomaterial used to fill the defect: coagulum (COA), deproteinized bovine bone (DBB), or biphasic calcium phosphate ceramics of hydroxyapatite and ß-phosphate tricalcium (HA/TCP). Euthanasia of the animals was performed 15 and 60 days after the surgical procedure (n = 5 animals/period/subgroup). Bone repair (formation) assessment was performed through microtomography and histometry, while the analyses of the expression of the BMP2, Osteocalcin, and TGFß1 proteins were performed using immunohistochemistry. The CSDs not filled with biomaterials demonstrated lower bone formation in the CCP group. At 15 days, less bone formation was observed in the CSDs filled with DBB, a smaller volume of mineralized tissue was observed in the CSDs filled with HA/TCP, and the expression levels of BMP2 and osteocalcin were lower in the CCP group compared to the CTR group. The use of cyclosporine impaired bone repair in CSD, and this effect can be partially explained by the suppression of BMP2 and osteocalcin expression.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Substitutos Ósseos/farmacologia , Inibidores de Calcineurina/farmacologia , Ciclosporina/farmacologia , Osteogênese/efeitos dos fármacos , Animais , Proteína Morfogenética Óssea 2/análise , Imuno-Histoquímica , Masculino , Osteocalcina/análise , Distribuição Aleatória , Ratos , Reprodutibilidade dos Testes , Crânio/efeitos dos fármacos , Crânio/patologia , Fatores de Tempo , Fator de Crescimento Transformador beta1/análise , Microtomografia por Raio-X
9.
J Appl Oral Sci ; 28: e20190435, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32049138

RESUMO

OBJECTIVE: To quantify the bone volume that can be safely withdrawn from 3 donor sites: (1) the mandibular symphysis, (2) the oblique mandibular line and (3) the skullcap. METHODOLOGY: For the symphysis, 200 tomographic exams were evaluated by the extension of the anterior loop of mental foramen, by the nerve, by the distance of the foramens, by the distance between the vestibular cortical and the lingual plates and by the distance between the apexes, or lower anterior teeth, and the mandibular base, using the "distance" tool of the I-CAT Vision, in the panoramic and parasagittal reformations. For the oblique line, 70 TCFC exams were analyzed retrospectively in panoramic and parasagittal reformations, evaluating the thickness of the vestibular cortical and the distance between the cortical and the mandibular canal. For the cranial bone, a hexagonal donor site located in parietal area was considered. RESULTS: The average dimensions of the bone blocks that can be safely removed from the region of the mandibular symphysis are: 32.27 mm in length, 4.87 mm in height and 4 mm in thickness, providing a volume of 628.61 mm3 available for grafting. In the oblique line, the available bone volume for grafting was 859.61 mm3. In the region of the cranial vault, multiplying the average bone thickness by the area of the hexagon, an average volume of 2,499 mm3 was obtained. CONCLUSIONS: Comparing the donor sites, the bone availability in the cranial vault is 3 times greater than in the mandibular posterior region, and at least 2 times greater than in the mandibular symphysis.


Assuntos
Transplante Ósseo/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Mandíbula/transplante , Crânio/transplante , Sítio Doador de Transplante , Adolescente , Adulto , Idoso , Pontos de Referência Anatômicos , Osso Cortical/diagnóstico por imagem , Osso Cortical/transplante , Feminino , Humanos , Masculino , Mandíbula/diagnóstico por imagem , Ilustração Médica , Pessoa de Meia-Idade , Estudos Retrospectivos , Crânio/diagnóstico por imagem , Sítio Doador de Transplante/diagnóstico por imagem , Adulto Jovem
11.
Plast Reconstr Surg ; 145(2): 337e-347e, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31985634

RESUMO

BACKGROUND: Three-dimensionally-printed bioceramic scaffolds composed of ß-tricalcium phosphate delivering the osteogenic agent dipyridamole can heal critically sized calvarial defects in skeletally mature translational models. However, this construct has yet to be applied to growing craniofacial models. In this study, the authors implanted three-dimensionally-printed bioceramic/dipyridamole scaffolds in a growing calvaria animal model and evaluated bone growth as a function of geometric scaffold design and dipyridamole concentration. Potential adverse effects on the growing suture were also evaluated. METHODS: Bilateral calvarial defects (10 mm) were created in 5-week-old (approximately 1.1 kg) New Zealand White rabbits (n = 16 analyzed). Three-dimensionally-printed bioceramic scaffolds were constructed in quadrant form composed of varying pore dimensions (220, 330, and 500 µm). Each scaffold was coated with collagen and soaked in varying concentrations of dipyridamole (100, 1000, and 10,000 µM). Controls consisted of empty defects. Animals were killed 8 weeks postoperatively. Calvariae were analyzed using micro-computed tomography, three-dimensional reconstruction, and nondecalcified histologic sectioning. RESULTS: Scaffold-induced bone growth was statistically greater than bone growth in empty defects (p = 0.02). Large scaffold pores, 500 µm, coated in 1000 µM dipyridamole yielded the most bone growth and lowest degree of scaffold presence within the defect. Histology showed vascularized woven and lamellar bone along with initial formation of vascular canals within the scaffold lattice. Micro-computed tomographic and histologic analysis revealed patent calvarial sutures without evidence of ectopic bone formation across all dipyridamole concentrations. CONCLUSION: The authors present an effective pediatric bone tissue-engineering scaffold design and dipyridamole concentration that is effective in augmentation of calvarial bone generation while preserving cranial suture patency.


Assuntos
Regeneração Óssea/efeitos dos fármacos , Fosfatos de Cálcio/uso terapêutico , Dipiridamol/uso terapêutico , Fraturas Cranianas/cirurgia , Engenharia Tecidual/métodos , Tecidos Suporte , Animais , Dipiridamol/administração & dosagem , Modelos Animais de Doenças , Coelhos , Crânio/efeitos dos fármacos , Crânio/lesões , Fraturas Cranianas/tratamento farmacológico
12.
Eur. j. anat ; 24(1): 49-56, ene. 2020. tab, ilus
Artigo em Inglês | IBECS | ID: ibc-186064

RESUMO

The anatomical variations of the intracranial venous dural sinuses must be put in consideration in diagnosing magnetic resonance venography (MRV) to avoid the diagnostic pitfalls resulting from over-diagnosis of cerebral venous dural sinus occlusion or thrombosis. The available data regarding the age and sex difference of the magnetic resonance venography (MRV) anatomical variations is still limited. A retrospective study is done for 500 patients ranging from 20 to 70 years. Only 363 patients (142 males and 221 females) were included in our final analysis: all have normal MRI brain & posterior fossa. Magnetic resonance venography (MRV) is done to detect the presence or absence of the transverse venous dural sinuses and to detect any age-or sex-related differences. Also 64 dry Egyptian skulls (41 males and 23 females) were employed to detect symmetry of transverse sulcus and to determine age and sex difference. Hypoplastic left transverse sinus was by far the commonest asymmetrical transverse sinus variants representing 22.0% of total: it was noted in 38 male and 38 female. Even if the asymmetrical transverse sinus is more common in females, there is no significant difference between both genders. In the dry skull, symmetrical transverse sulcus was observed in 67.2% of total, while asymmetrical transverse sulcus was recorded in 32.8% of total, which were more observed in female skull 17.2% of total with no significant difference


No disponible


Assuntos
Humanos , Masculino , Feminino , Adulto , Pessoa de Meia-Idade , Idoso , Variação Anatômica , Flebografia/métodos , Cavidades Cranianas/anormalidades , Cavidades Cranianas/diagnóstico por imagem , Trombose dos Seios Intracranianos/diagnóstico por imagem , Crânio/anormalidades , Crânio/anatomia & histologia , Imagem por Ressonância Magnética , Espectroscopia de Ressonância Magnética , Cavidades Cranianas/anatomia & histologia , Estudos Retrospectivos , Diferenciação Sexual , Egito , Determinação da Idade pelo Esqueleto , Crânio/diagnóstico por imagem
13.
Adv Exp Med Biol ; 1232: 33-38, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-31893391

RESUMO

Monitoring of cerebral tissue oxygen saturation (StO2) by near-infrared spectroscopy (NIRS oximetry) has great potential to reduce the incidence of hypoxic and hyperoxic events and thus prevent long-term disabilities in preterm neonates. Since the light has to penetrate superficial layers (bone, skin and cerebrospinal fluid) before it reaches the brain, the question arises whether these layers influence cerebral StO2 measurement. We assessed this influence on the accuracy of cerebral StO2 values. For that purpose, we simulated light propagation with 'N-layered medium' software. It was found that with a superficial layer thickness of ≤6 mm, typical for term and preterm neonates, StO2 accurately reflects cerebral tissue oxygenation.


Assuntos
Oximetria , Oxigênio , Crânio , Encéfalo/metabolismo , Humanos , Hipóxia/diagnóstico , Recém-Nascido , Oximetria/normas , Crânio/anatomia & histologia , Espectroscopia de Luz Próxima ao Infravermelho
15.
Dentomaxillofac Radiol ; 49(3): 20190315, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31697180

RESUMO

OBJECTIVES: To assess presence and severity of image-stitching artefacts and distortion in lateral cephalograms acquired by CCD-based sensors and their association with movement. METHODS: A human skull was mounted on a robot simulating five head movement types (anteroposterior translation/lifting/nodding/lateral rotation/tremor), at three distances (0.75/1.5/3 mm), based on two patterns (skull returning/not returning to the initial position, except for tremor). Three cephalometric units, two ProMax-2D (Planmeca Oy, Finland), one with Dimax-3 (D-3) and one with Dimax-4 (D-4) sensor, and one Orthophos-SL (ORT, Dentsply-Sirona, Germany), acquired cephalograms during the predetermined movements, in duplicate (54 with movement and 28 controls with no movement per unit). One observer assessed the presence of an image-stitching line (none/thin/thin with vertical stripes or thick), misalignment between the anatomical structure display (none/<1/1-3/>3 mm), and distortion in each image quadrant (present/absent), in duplicate. Severe image-stitching artefacts were defined for images scored with a thin line with vertical stripes or thick line and/or misalignment between anatomical structure display ≥1 mm. Severe distortion was defined for images scored with distortion in both anterior quadrants of the skull. κ-statistics provided intraobserver agreement. RESULTS: Intraobserver reproducibility was >0.8 (all assessed parameters). Severe image-stitching artefacts were scored in 70.4 and 18.5% of D-3 and D-4 movement images, respectively. Severe distortion was scored in 64.8% of D-3, 5.6% of D-4 and 37% of ORT movement images. Neither severe image-stitching artefacts nor severe distortion were observed in control images. CONCLUSION: Sensor type, movement type, distance and pattern affected presence and severity of image-stitching artefacts and distortion in CCD-based cephalograms.


Assuntos
Artefatos , Tomografia Computadorizada de Feixe Cônico , Movimentos da Cabeça , Humanos , Movimento , Reprodutibilidade dos Testes , Crânio/diagnóstico por imagem
16.
Toxicol Lett ; 319: 250-255, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31778774

RESUMO

The effect of thalidomide on mandibular development is unclear. In this study, thalidomide was delivered to pregnant rabbits from the 8th to 14th day of gestation. Then, embryos were harvested for examination on the 16th day (GD16), 20th day (GD20) and 24th day (GD24) of gestation. The results showed obvious hemorrhage and hematoma on one side of the craniofacial region in 50 % of the thalidomide-treated embryos and obvious hemorrhage and hematoma on both sides of the craniofacial region in 50 % of the thalidomide-treated embryos at GD16. Histological examination showed soft tissues and mandible defects on the affected side of the maxillofacial region. The expression of Vegf-α, Ki67 and Sox9 on the affected side was significantly down-regulated in comparison to their expression on the unaffected side at GD20. There was also an obvious defect in the affected mandible, and the density of the skull and mandible was decreased compared to the unaffected side or the control group at GD24. These findings demonstrated that thalidomide may lead to hemorrhage and hematoma in the craniofacial region by inhibiting angiogenesis, resulting in the abnormal development of cranial neural crest cells that are involved in the normal development of the mandible in rabbits.


Assuntos
Anormalidades Craniofaciais/induzido quimicamente , Anormalidades Craniofaciais/patologia , Hemorragia/induzido quimicamente , Hemorragia/patologia , Mandíbula/patologia , Neovascularização Fisiológica/efeitos dos fármacos , Teratogênios/toxicidade , Talidomida/toxicidade , Animais , Regulação para Baixo/efeitos dos fármacos , Feminino , Mandíbula/anormalidades , Anormalidades Maxilofaciais/induzido quimicamente , Anormalidades Maxilofaciais/patologia , Crista Neural/patologia , Gravidez , Coelhos , Crânio/anormalidades
17.
World Neurosurg ; 133: e627-e632, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31568916

RESUMO

BACKGROUND: Decompressive craniectomy (DC) is a surgical procedure performed to manage intracranial hypertension. Once performed, patients are obligated to undergo another surgical procedure known as cranioplasty to reconstruct the cranial defect. Cranioplasty still has one of the highest rates of infection. The factors contributing to the high rate of surgical site infection (SSI) after cranioplasty are not well established. This study aims to estimate the incidence of SSI and determine its possible risk factors for patients who underwent cranioplasty using bone flaps subcutaneously preserved in abdominal pockets. METHODS: A retrospective cohort study was conducted to investigate the predictors of infection among patients who underwent cranioplasty from subcutaneously preserved bone flaps in abdominal pockets between January 2005 and December 2018 at a level l trauma center. RESULTS: A total of 103 cases of cranioplasty from subcutaneously preserved bone flaps were included in the study. The mean age of the patients was 31.2 ± 14.8 years (range, 5-67 years). The median interval between DC and cranioplasty was 115 days. The most frequent indication for DC was traumatic brain injury (76.4%). The incidence of SSI was noted in 15.7% of patients. The most significant predictors of infection in patients requiring cranioplasty were blood glucose levels and skull defect size (P = 0.03 and P = 0.02, respectively). CONCLUSIONS: Blood glucose levels and skull defect size were the only identifiable risk factors associated with SSI. Storing bone flaps in subcutaneous abdominal pockets is cost-efficient but carries considerable risk of infection.


Assuntos
Procedimentos Cirúrgicos Reconstrutivos/efeitos adversos , Procedimentos Cirúrgicos Reconstrutivos/métodos , Retalhos Cirúrgicos , Infecção da Ferida Cirúrgica/epidemiologia , Infecção da Ferida Cirúrgica/etiologia , Adolescente , Adulto , Idoso , Criança , Estudos de Coortes , Craniectomia Descompressiva/efeitos adversos , Feminino , Humanos , Incidência , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Fatores de Risco , Crânio/cirurgia , Adulto Jovem
18.
Clin Oral Implants Res ; 31(1): 10-17, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31529644

RESUMO

OBJECTIVES: Deproteinized bovine bone mineral (DBBM) is not resorbable. However, the behavior of DBBM under inflammatory conditions remains unclear. Aim of the study was therefore to evaluate the resorption of DBBM under local inflammatory conditions in vivo using the calvarial osteolysis model. METHODS: In thirty adult BALB/c mice, DBBM was implanted into the space between the elevated soft tissue and the calvarial bone. Inflammation was induced either by lipopolysaccharides (LPS) injection or by polyethylene particles (Ceridust) mixed with DBBM. Three modalities were randomly applied (n = 10 each): (a) DBBM alone (control), (b) DBBM + LPS, and (c) DBBM + polyethylene particles (Ceridust). Mice were euthanized on day fourteen, and each calvarium was subjected to histological and µCT analysis. Primary outcome was the size distribution of the DBBM particles. Secondary outcome was the surface erosion of the calvarial bone. RESULTS: Histological and µCT analysis revealed that the size distribution and the volume of DBBM particles in the augmented site were similar between DBBM alone and the combinations with LPS or polyethylene particles. Moreover, histological evaluation showed no signs of erosions of DBBM particles under inflammatory conditions. µCT analysis and histology further revealed that LPS and the polyethylene particles, but not the DBBM alone, caused severe erosions of the calvarial bone as indicated by large voids representing the massive compensatory new immature woven bone formation on the endosteal surface. CONCLUSIONS: Local calvarial bone but not the DBBM particles undergo severe resorption and subsequent new bone formation under inflammatory conditions in a mouse model.


Assuntos
Substitutos Ósseos , Animais , Regeneração Óssea , Bovinos , Modelos Animais de Doenças , Camundongos , Camundongos Endogâmicos BALB C , Minerais , Crânio
19.
World Neurosurg ; 133: e293-e302, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31520764

RESUMO

OBJECTIVE: Interest in endoscopic transnasal access has increased with continued technological advances in endoscopic technology. The goals of this study were to review the normal anatomy in transnasal endoscopic neurosurgery and outline the anatomical basis for an expanded surgical approach. Defining anatomical aspects of surgical endoscopy helps guide the surgeon by defining normal anatomy of the access vector. METHODS: This anatomic study was conducted on 15 adult male cadaver specimens using various microsurgical tools and endoscopic instruments and 1 intraoperative case. The vasculature was injected with colored silicone to aid visualization. Different transnasal approach techniques were used, with angles of endoscope access at 0°, 30°, 45°, and 70° accordingly for extensive anatomical mapping. RESULTS: The proximity of critical structures is different in each approach degree. A full understanding of the possible structures to be met during transnasal access is described. As a result of the study, anatomical aspects and important structures were outlined, and a surgical protocol was defined for minimal risk access in respect to normal anatomy of the area. CONCLUSIONS: Thorough knowledge of topographic anatomy of the craniovertebral junction is required for performing minimal-risk surgical intervention in this region. It is important to know all anatomical aspects of the transnasal approach in order to reduce the risk of damage to vital structures. Transnasal endoscopic surgery of the craniovertebral junction is a relatively new direction in neurosurgery; therefore, anatomical studies such as the one described in this article are extremely important for the development of this access method.


Assuntos
Cirurgia Endoscópica por Orifício Natural/métodos , Neuroendoscopia/métodos , Adulto , Cadáver , Vértebras Cervicais/anatomia & histologia , Humanos , Masculino , Cavidade Nasal , Crânio/anatomia & histologia
20.
World Neurosurg ; 133: e850-e873, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31541755

RESUMO

OBJECTIVE: The recent emphasis on simulation-based training in neurosurgery has led to the development of many simulation models and training courses. We aim to identify the currently available simulators and training courses for neurosurgery, assess their validity, and determine their effectiveness. METHODS: Both MEDLINE and Embase were searched for English language articles which validate simulation models for neurosurgery. Each study was screened according to the Messick validity framework and rated in each domain. The McGaghie model of translational outcomes was then used to determine a level of effectiveness (LoE) for each simulator or training course. RESULTS: On screening of 6006 articles, 114 were identified to either validate or determine an LoE for 108 simulation-based training models or courses. Achieving the highest rating for each validity domain were 6 models and training courses for content validity, 12 for response processes, 4 for internal structure, 14 for relations to other variables, and none for consequences. For translational outcomes, 6 simulators or training achieved an LoE >2 and thus showed skills transfer beyond the simulation setting. CONCLUSIONS: With the advent of increasing neurosurgery simulators and training tools, there is a need for more validity studies. Further attempts to investigate translational outcomes to the operating theater when using these simulators is particularly warranted. More training tools incorporating full-immersion simulation and nontechnical skills training are recommended.


Assuntos
Encéfalo/cirurgia , Competência Clínica , Procedimentos Neurocirúrgicos/educação , Treinamento por Simulação/métodos , Crânio/cirurgia , Humanos
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