Physical cones equipped on GammaKnife, Cyberknife, and C-arm linacs have been the standard practice in Stereotactic Ablative Radiotherapy (SART) for small intracranial lesions, such as treating trigeminal or glossopharyngeal neuralgia targets. The advancement of high-definition multi-leaf collimators (HDMLC), treatment planning systems, and small field dosimetry now allows for treatment without the need for an auxiliary mounted physical cone. This treatment type uses the “virtual cone”, a permanent high-definition MLC, arrangement to deliver “very small fields” with comparable spherical dose distributions to physical cones. The virtual cone therapy, on a Varian Edge™ linac using multiple non-coplanar arcs with static HDMLCs, is a comparable technique that can be used to treat small intracranial neuralgia or other small lesions. In this investigation, two flattening filter free (FFF) photon beams, 6MV FFF and 10MV FFF, were tested for optimal delivery and safety conditions for treating intracranial lesions. The virtual cone method on a Varian Edge™ Linear accelerator using rapid arc stereotactic radiosurgery was used to treat cranial neuralgia for chronic pain for six patients. Absolute dose, relative dose measurements, and monitor units were the main characteristics that were examined to decide which energy was the best for treatment. Source-to-axis distances (SAD) of 100cm measurements were taken at depths of 10cm and 5cm, respectively. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2020. / FAU Electronic Theses and Dissertations Collection

Thesis (M. S. in Biomedical Engineering)--Vanderbilt University, Dec. 2007. / Title from title screen. Includes bibliographical references.

Proefschrift--Groningen. / Summary in Dutch and French.

Proefschrift--Groningen. / Summary in Dutch and French.

Dissertation (Ph.D.).--University of Texas Graduate School of Biomedical Sciences at San Antonio, 2008. / Vita. Includes bibliographical references.

Thesis (M.S.)--State University of New York at Binghamton, Department of Physics, Applied Physics and Astronomy, 2009. / Includes bibliographical references.

Thesis (M.S. in Electrical Engineering)--Vanderbilt University, May 2005. / Title from title screen. Includes bibliographical references.

Orientador: Helder Tedeschi / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Ciencias Medicas / Made available in DSpace on 2018-08-14T16:36:45Z (GMT). No. of bitstreams: 1 Sarmento_StenioAbrantes_D.pdf: 8005225 bytes, checksum: 536dc762dc674f3a764c2acd713848f5 (MD5) Previous issue date: 2009 / Resumo: Nos últimos anos, consideráveis avanços tecnológicos, principalmente métodos de localização funcional do córtex cerebral, têm surgido no sentido de melhorar os resultados cirúrgicos no tratamento de lesões em áreas eloqüentes. O objetivo deste estudo é avaliar os resultados pós-operatórios em 74 pacientes submetidos à ressecção de lesões em área motora ou adjacente, utilizando-se de planejamento com exames de neuroimagem, conhecimento anatômico, técnica microcirúrgica adequada e métodos auxiliares a exemplo da estimulação intra-operatória. Glioma foi o diagnóstico histopatológico em 32 pacientes (43,2%), seguido de meningeoma em 19 pacientes (25,6%), metástase em 11 pacientes (14,8%) %), cavernoma em 5 (6,8%), linfoma primário em 02 pacientes, cisticercose em 2, displasia em 2 (2,7%) e processo inflamatório inespecífico em 1 paciente (1,4%). A ressecção cirúrgica foi considerada total em 68 (93,1%) pacientes e subtotal em 05 (6,84%). 54 pacientes (73,9%) apresentavam força muscular normal (grau 5) no préoperatório. Destes, 20 (37,3%) apresentaram déficit no pós-operatório imediato, sendo que 17 (85%) recuperaram completamente o déficit em até 3 meses e 3 pacientes apresentaram melhora parcial. 19 pacientes apresentavam déficit no pré-operatório. Destes, 05 apresentaram piora do déficit no pós-operatório imediato (sendo que 04 (80%) tiveram melhora no pós-operatório tardio) e 02 melhoraram já no pós- operatório imediato. A estimulação intra-operatória foi utilizada em 65% dos casos, principalmente nos gliomas, e, estereotaxia nos pacientes com cavernomas. Concluímos que a morbidade em pacientes operados de lesões em área motora é bastante aceitável e justifica a indicação cirúrgica com tentativa de ressecção máxima. As lesões extrínsecas (meningeomas e metástases) podem ser completamente ressecadas com baixa morbidade, sem nenhum método adicional, apenas conhecimento anatômico e técnica cirúrgica adequada. A estimulação intra-operatória foi fundamental para guiar a ressecção em grande parte dos gliomas. Não houve diferença na morbidade e nem no grau de ressecção quando comparamos os nossos resultados com aqueles da literatura em que usam métodos funcionais de imagem, neuronavegação ou outros métodos como a ressonância intraoperatória. Lesões subcorticais, como por exemplo, cavernomas podem ser tratadas utilizando apenas estereotaxia. / Abstract: In recent years considerable technological advances have been made with the purpose of improving the surgical results in the treatment of eloquent lesions. The overall aim of this study is to evaluate the postoperative surgical outcome in 74 patients who underwent surgery to remove lesions around the motor area, in which preoperative planning by using neuroimaging exams, anatomical study, appropriate microsurgery technique and auxiliary methods such as intraoperative stimulation were performed. Glioma was the histological diagnosis in thirty two patients (43,2%) follow by meningeoma in nineteen patients (25,6%), metastasis in eleven patients (14,8%), cavernoma in five (6,8%), primary linfoma in two patients, cisticercus in two, cortical dysplasia in two (2,7%) and inflammatory lesion in one patient (1,4%). Gross total removal was achieved in sixty-eight (93,1%) patients and subtotal in five (6,84%). Fifty-four patients (73,9%) presented a normal motor function in the preoperative period. Of these, twenty (37,3%) developed transitory deficit, nevertheless 85% of these presented a complete recovery later and three evolved with partial improvement. Nineteen patients presented a motor deficit preoperatively. Of these, five presented deterioration, but four patients improved later and two patients recovery in the early post-operative. The intraoperative stimulation was used in 65% of the patients, mainly in gliomas. Stereotaxy was used in patients with cavernoma. We concluded that the resection of lesions in motor areas is feasible. Lesions such as meningeomas and metastasis can be safely operated on without the necessity of auxiliary methods by using anatomic knowledge and appropriate surgical technique only. Intraoperative stimulation was very important to guide the resection in many cases of gliomas. There was no difference in the morbidity and resection grade when we compared our results with those who use image functional methods, neuronavegation system or other methods such as intraoperative magnetic resonance image in surgery around the motor area. Subcortical small lesions such as cavernoma can be treated by using stereotaxy techniques. / Doutorado / Neurologia / Doutor em Ciências Médicas

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