Thesis (M.D.S.)--University of Hong Kong, 1991. / Includes bibliographical references (p. 258-271). Also available in print.

published_or_final_version / Dentistry / Master / Master of Dental Surgery

Thesis (M.S.)--University of Michigan, 1959.

Thesis (MSD) --Boston University, Henry M. Goldman School of Dental Medicine, 2015 (Department of Orthodontics and Dentofacial Orthopedics). / Includes bibliographic references: leaves 37-42. / Background: Craniofacial skeletal asymmetry is a common finding in the general population that often goes undetected. Interest in this topic has led to many studies aimed at describing this type of asymmetry, its distribution and etioIogy. The cranial base, being cIosely related to the face and brain, is a key component in craniofacial growth and may also display varying amounts of asymmetry contributing to this anomaly. Though many studies have explored underlying skeletal asymmetry, most of them were limited by their two-dimensional method of investigation. With the advent of three-dimensional technology, more recent studies have had the advantage of studying the cranial base in its true anatomic form, resulting in greater accuracy of analysis. Despite access to this technoIogy, there is still a lack of literature regarding the cranial base in a normal population. Determining average skull base dimensions will provide a set of normative data that can be used as a reference for future studies. Material and Methods: Pre-treatment Cone Beam Computed Tomography (CBCT) films of 160 esthetic human subjects previously used by another investigator were screened for use in our current research. These DICOM files were imported into InVivoDental5.3 software (Anatomage[TM]; San Jose, Calif.) for screening and 70 CBCT scans were selected for analysis. All patients were classified as cervical vertebral stage 4 and above. The images were oriented in all three planes of space for uniformity and 14 bilateral anatomic landmarks were identified on each scan. A mid-sagittal reference plane was created using crista galli as the origin, and extending a perpendicular passing through the middle of the right and left clinoid points connected by a line, and through posterior points basion and opisthion. Each landmark was given an x-, y- and z- coordinate representing its three dimensional position and bilateral linear measurements to the reference plane were recorded using the software system. Statistical Analysis: InVivoDental5.3 software was used to calculate linear distances between each landmark and the mid-sagittal plane. This data was exported into Microsoft excel for analysis. Descriptive statistics of our sample and paired t-tests with a 5% significance level, or p value of 0.05, were performed. Results: The means of the right and left measurements of each bilateral landmark were calculated along with their standard deviations. A comparison between right and left means was accomplished with the use of paired t-tests. 12 1andmarks did not show a statistical difference in their locations on either side of the mid-sagittal plane. However, the means of 2 landmarks were found to be statistically significant. These were euryon (p = 0.01) and the jugular foramen (p = 0.00) Conclusion: The overall trend of our data indicated that the cranial base in a normal population, without craniofacial anomaly, displays symmetry, with the exception of the location of euryon and the jugular foramen. These findings are in accordance with those of similar three-dimensional studies. It is likely that the significant findings were due to tracing error, given the indiscrete location of euryon and the large, relatively asymmetric shape of the jugular foramen. However, if these structures are truly asymmetric, we can infer from our sample of symmetric patients, that there is no clinical relevance. Further studies with an increased sample size, additional landmarks or a more discrete sample can be performed to continue describing the skull base. The results of this study offer valuable reference data that can be used as a baseline for future studies.

Introduction Advanced Kadish stage esthesioneuroblastoma requires more extensive resections and aggressive adjuvant therapy to obtain adequate disease-free control, which can lead to higher complication rates. We describe the case of a patient with Kadish D esthesioneuroblastoma who underwent multiple surgeries for infectious, neurologic, and wound complications, highlighting potential preventative and salvage techniques. Case Presentation A 61-year-old man who presented with a large left-sided esthesioneuroblastoma, extending into the orbit, frontal lobe, and parapharyngeal nodes. He underwent margin-free endoscopic-assisted craniofacial resection with adjuvant craniofacial and cervical radiotherapy and concomitant chemotherapy. He then returned with breakdown of his skull base reconstruction and subsequent frontal infections and ultimately received 10 surgical procedures with surgeries for infection-related issues including craniectomy and abscess evacuation. He also had surgeries for skull base reconstruction and CSF leak, repaired with vascularized and free autologous grafts and flaps, synthetic tissues, and CSF diversion. Discussion Extensive, high Kadish stage tumors necessitate radical surgical resection, radiation, and chemotherapy, which can lead to complications. Ultimately, there are several options available to surgeons, and although precautions should be taken whenever possible, risk of wound breakdown, leak, or infection should not preclude radical surgical resection and aggressive adjuvant therapies in the treatment of esthesioneuroblastoma.

Introdução: O uso do retalho nasosseptal (NS) para a reconstrução endoscópica da base do crânio foi fator fundamental para o avanço dos acessos endonasais expandidos. Objetivos: Aferir as dimensões do retalho NS e do defeito da base do crânio anterior (BCA) após ressecção craniofacial endoscópica e verificar a suficiência do retalho para cobrir o defeito. Estudar a anatomia da artéria septal (AS) e sua relação com o óstio do seio esfenoide. Métodos: Estudo anatômico do retalho NS em 14 cadáveres. Após ressecção craniofacial endoscópica, foi verificado a suficiência do retalho em cobrir o defeito na BCA. A AS foi dissecada e estuda quanto ao número de ramos presentes no pedículo e sua distância em relação ao óstio do seio esfenoide. Estudo radiológico com tomografia computadorizada de 30 pacientes para a comparação entre medidas do retalho NS e as do defeito na BCA. Resultados: O retalho foi suficiente para cobrir o defeito na BCA nas 14 dissecções. Em 71,4% dos casos, dois ramos da AS foram encontrados no pedículo. A distância média entre o primeiro ou único ramo ao óstio do esfenoide foi de 9,3mm. No estudo radiológico, a média da área reconstrutora do retalho (17,12cm2) foi constantemente maior que a média da área do defeito (8,64cm2) (p<0,001). A diferença entre o comprimento superior do retalho e a distância anteroposterior do defeito foi menor ou igual a 5mm em 26,7% dos casos. A comparação entre a largura anterior do retalho e a distância interorbitária anterior revelou que em 33% dos casos a diferença foi 5mm. A incorporação da mucosa do assoalho da fossa nasal ao retalho aumentou essa diferença em mais 10mm em todos os casos. Conclusões: As dimensões do retalho NS são suficientes para cobrir o defeito na BCA. A extremidade anterior do comprimento anteroposterior do defeito apresenta maior risco de falha de cobertura. A incorporação da mucosa do assoalho da fossa nasal ao retalho é importante para diminuir o risco de falha de cobertura anterior na largura do defeito. Em geral, é mais comum a presença de dois ramos da AS no pedículo / Introduction: Use of the nasoseptal (NS) flap for endoscopic skull base reconstruction was an essential contribution for the evolution of the expanded endonasal approaches. Objectives: Measure the dimensions of the NS flap and the anterior skull base (ASB) defect after endoscopic craniofacial resection and verify if the flap is sufficient to cover the defect. Study the anatomy of the septal artery (SA) and its relation with the sphenoid ostium. Methods: Anatomical study of the NS flap in 14 cadavers. After endoscopic craniofacial resection, the sufficiency of the flap to cover the ASB defect was assessed. The SA was dissected and studied regarding the number of branches in the pedicle and the distance between the artery and the sphenoid ostium. Radiological study using CT scans of 30 patients for comparison among measurements of the NS flap and the ASB defect. Results: The flap was sufficient to cover the ASB in all 14 dissections. In 71.4% of the cases, 2 branches of the SA were found in the pedicle. The distance between the first or the only single branch of the SA to the sphenoid ostium was 9.3mm. In the radiological study, the reconstruction area of the flap (17.12cm2) was constantly larger than the defect area (8.64cm2) (p<0.001). The difference between the superior length of the flap and the anterior-posterior distance of the defect was 5mm in 26.7% of the cases. Comparison between the flap anterior width and the defect anterior width revealed that in 33% the difference was 5mm. The incorporation of the nasal floor mucosa to the flap increased that difference in more than 10mm in all cases. Conclusions: The dimensions of the NS flap are sufficient to cover completely the ASB defect. The anterior edge of the anterior-posterior length of the defect presents increased risk for failure in coverage. The additional width provided by the incorporation of the nasal floor mucosa to the flap is important to decrease the risk of failure in coverage of the anterior defect width. In general, it is more common to find 2 branches of the SA in the pedicle

Meningiomas petroclivais são tumores da base do crânio desafiadores para ressecção cirúrgica devido a sua localização profunda e relação com estruturas neurovasculares vitais. Geralmente são lesões benignas, mas podem envolver ou infiltrar o osso da base do crânio, dura-máter, tronco encefálico e todas as estruturas neurovasculares desta região, tornando a remoção total difícil sem causar déficits neurológicos. O objetivo deste estudo é revisar uma série de casos de meningiomas petroclivais tratados cirurgicamente em centro de referência de base de crânio, considerando os fatores determinantes para a escolha da abordagem. A casuística foi analisada com coleta retrospectiva dos dados. Devido à dificuldade de acesso, essas lesões geralmente requerem diferentes abordagens cirúrgicas e apresentam dificuldades cirúrgicas distintas. Embora as abordagens fronto-órbito-zigomática, petrosas, incluindo présigmoide retrolabiríntica, translabiríntica e petrosectomia total, e a retrossigmoide sejam as mais utilizadas para ressecção destes tumores, não foi realizado até o presente momento estudo comparativo que determine qual abordagem apresenta maior grau de ressecção cirúrgica associada a menor taxa de morbidade. / Petroclival meningiomas are challenging skull base tumors for surgical resection because of its deep location and their relationship to vital neurovascular structures. They are usually benign, but may involve or infiltrate the bone of the skull base, dura, brain stem and all neurovascular structures in this region, making it difficult to completely remove without causing neurological deficits. The aim of this study is to review a surgical series of petroclival meningioma treated in a referral center for skull base tumors, considering the determining factors to the choice of approach. The casuistry was analyzed with retrospective data collection. Due to difficult access, these injuries usually require different surgical approaches and have different surgical difficulties. Although the fronto-orbital-zygomatic, petrous, including retrolabyrinthine pre-sigmoid, translabyrinthine and total petrosectomy, and retrosigmoid are frequently used for resection of these tumors, it has not been realized to date comparative study to determine which approach has greater degree of surgical resection associated with lower morbidity rate.

Craniostenose é o fechamento precoce de uma ou mais suturas cranianas, levando ao redirecionamento do crescimento craniofacial e à deformidade do crânio. Estudos têm pesquisado o impacto da fusão da sutura sagital na base do crânio, focalizando a morfologia da base do crânio na presença de craniostenose sagital isolada (escafocefalia), enquanto outros têm avaliado o crescimento da base do crânio, antes e após a cirurgia. Este estudo teve como objetivo realizar as medidas antropométricas da base do crânio em crianças com escafocefalia, avaliar a influência da correção cirúrgica no remodelamento da base do crânio e nas medidas antropométricas. Foram operadas 21 crianças com diagnóstico clínico e radiológico de escafocefalia, entre abril de 2007 e outubro de 2008, sendo realizadas medidas antropométricas na base do crânio, antes e após 1 ano do tratamento cirúrgico. As medidas foram o índice craniano (IC), distância entre a crista galli e o tubérculo selar (CG-TS), distância entre a crista galli e o meato acústico interno (CG-MAI), distância entre os forames ovais (FO-FO), distância entre os meatos Acústicos internos (MAI-MAI), o ângulo da base do crânio Â1) e o ângulo entre o násio, centro selar e básio (Â2). Houve normalização do IC em todas as crianças, confirmando um remodelamento craniano adequado. A medida CG-TS avaliou a base do crânio anterior, com crescimento proporcional de 12,5%. O crescimento médio-lateral foi observado pelo aumento das medidas FO-FO de 8,5% e MAI-MAI de 9,5%. A medida CG-MAI teve um crescimento de 7,2%. Não houve diferença estatística nos ângulos basais Â1 e Â2 analisados. O tratamento cirúrgico da escafocefalia levou ao remodelamento da base do crânio, confirmado pelas mudanças das medidas antropométricas realizadas antes e após 1 ano da cirurgia / Craniosynostosis is defined as the premature closure of one or more sutures, leading to redirection of the craniofacial growth and deformity of the skull. Studies have examined the impact of fusion of the sagittal suture in the skull base, focusing on the morphology of the skull base in the presence of isolated sagittal craniosynostosis (scaphocephaly), while others have evaluated the growth of the skull base before and after surgery. This study aims to perform the anthropometric measures of the skull base in children with scaphocephaly to evaluate the influence of surgical repair in the remodeling of the skull base and anthropometric measures. Twenty-one children with clinical and radiological diagnosis of scaphocephaly were operated between April 2007 and October 2008, and anthropometric measures at the base of the skull were performed before and after a year of surgery. The measures were the cranial index (CI), distance between the crista galli and tuberculum sellar (CG-TS), distance between the crista galli and the internal auditory meatus (CG-IAM), distance between the oval foramen (OF-OF) distance between the internal auditory meatus (IAM-IAM), the angle of the skull base (Â1) and the angle between the nasion, center of sella and basion (Â2). There was a normalization of the CI in all children, confirming an appropriate cranial remodeling. The CG-TS measure evaluated the anterior skull base, with proportional growth of 12.5%. The mediolateral growth was observed by the increase of OF-OF measures by 8.5% and IAM-IAM by 9.5%. The CG-IAM measure grew by 7.2%. There was no statistical difference in the angles Â1 and Â2 analyzed. Surgical treatment of scaphocephaly led to remodeling of the skull base, confirmed by the changes of anthropometric measures taken before and after a year of surgery

Craniostenose é o fechamento precoce de uma ou mais suturas cranianas, levando ao redirecionamento do crescimento craniofacial e à deformidade do crânio. Estudos têm pesquisado o impacto da fusão da sutura sagital na base do crânio, focalizando a morfologia da base do crânio na presença de craniostenose sagital isolada (escafocefalia), enquanto outros têm avaliado o crescimento da base do crânio, antes e após a cirurgia. Este estudo teve como objetivo realizar as medidas antropométricas da base do crânio em crianças com escafocefalia, avaliar a influência da correção cirúrgica no remodelamento da base do crânio e nas medidas antropométricas. Foram operadas 21 crianças com diagnóstico clínico e radiológico de escafocefalia, entre abril de 2007 e outubro de 2008, sendo realizadas medidas antropométricas na base do crânio, antes e após 1 ano do tratamento cirúrgico. As medidas foram o índice craniano (IC), distância entre a crista galli e o tubérculo selar (CG-TS), distância entre a crista galli e o meato acústico interno (CG-MAI), distância entre os forames ovais (FO-FO), distância entre os meatos Acústicos internos (MAI-MAI), o ângulo da base do crânio Â1) e o ângulo entre o násio, centro selar e básio (Â2). Houve normalização do IC em todas as crianças, confirmando um remodelamento craniano adequado. A medida CG-TS avaliou a base do crânio anterior, com crescimento proporcional de 12,5%. O crescimento médio-lateral foi observado pelo aumento das medidas FO-FO de 8,5% e MAI-MAI de 9,5%. A medida CG-MAI teve um crescimento de 7,2%. Não houve diferença estatística nos ângulos basais Â1 e Â2 analisados. O tratamento cirúrgico da escafocefalia levou ao remodelamento da base do crânio, confirmado pelas mudanças das medidas antropométricas realizadas antes e após 1 ano da cirurgia / Craniosynostosis is defined as the premature closure of one or more sutures, leading to redirection of the craniofacial growth and deformity of the skull. Studies have examined the impact of fusion of the sagittal suture in the skull base, focusing on the morphology of the skull base in the presence of isolated sagittal craniosynostosis (scaphocephaly), while others have evaluated the growth of the skull base before and after surgery. This study aims to perform the anthropometric measures of the skull base in children with scaphocephaly to evaluate the influence of surgical repair in the remodeling of the skull base and anthropometric measures. Twenty-one children with clinical and radiological diagnosis of scaphocephaly were operated between April 2007 and October 2008, and anthropometric measures at the base of the skull were performed before and after a year of surgery. The measures were the cranial index (CI), distance between the crista galli and tuberculum sellar (CG-TS), distance between the crista galli and the internal auditory meatus (CG-IAM), distance between the oval foramen (OF-OF) distance between the internal auditory meatus (IAM-IAM), the angle of the skull base (Â1) and the angle between the nasion, center of sella and basion (Â2). There was a normalization of the CI in all children, confirming an appropriate cranial remodeling. The CG-TS measure evaluated the anterior skull base, with proportional growth of 12.5%. The mediolateral growth was observed by the increase of OF-OF measures by 8.5% and IAM-IAM by 9.5%. The CG-IAM measure grew by 7.2%. There was no statistical difference in the angles Â1 and Â2 analyzed. Surgical treatment of scaphocephaly led to remodeling of the skull base, confirmed by the changes of anthropometric measures taken before and after a year of surgery

Meningiomas petroclivais são tumores da base do crânio desafiadores para ressecção cirúrgica devido a sua localização profunda e relação com estruturas neurovasculares vitais. Geralmente são lesões benignas, mas podem envolver ou infiltrar o osso da base do crânio, dura-máter, tronco encefálico e todas as estruturas neurovasculares desta região, tornando a remoção total difícil sem causar déficits neurológicos. O objetivo deste estudo é revisar uma série de casos de meningiomas petroclivais tratados cirurgicamente em centro de referência de base de crânio, considerando os fatores determinantes para a escolha da abordagem. A casuística foi analisada com coleta retrospectiva dos dados. Devido à dificuldade de acesso, essas lesões geralmente requerem diferentes abordagens cirúrgicas e apresentam dificuldades cirúrgicas distintas. Embora as abordagens fronto-órbito-zigomática, petrosas, incluindo présigmoide retrolabiríntica, translabiríntica e petrosectomia total, e a retrossigmoide sejam as mais utilizadas para ressecção destes tumores, não foi realizado até o presente momento estudo comparativo que determine qual abordagem apresenta maior grau de ressecção cirúrgica associada a menor taxa de morbidade. / Petroclival meningiomas are challenging skull base tumors for surgical resection because of its deep location and their relationship to vital neurovascular structures. They are usually benign, but may involve or infiltrate the bone of the skull base, dura, brain stem and all neurovascular structures in this region, making it difficult to completely remove without causing neurological deficits. The aim of this study is to review a surgical series of petroclival meningioma treated in a referral center for skull base tumors, considering the determining factors to the choice of approach. The casuistry was analyzed with retrospective data collection. Due to difficult access, these injuries usually require different surgical approaches and have different surgical difficulties. Although the fronto-orbital-zygomatic, petrous, including retrolabyrinthine pre-sigmoid, translabyrinthine and total petrosectomy, and retrosigmoid are frequently used for resection of these tumors, it has not been realized to date comparative study to determine which approach has greater degree of surgical resection associated with lower morbidity rate.