ELOISA MARIA MELLO SANTIAGO GEBRIM
Projetos de Pesquisa
Unidades Organizacionais
Instituto de Radiologia, Hospital das Clínicas, Faculdade de Medicina - Médico
6 resultados
Resultados de Busca
Agora exibindo 1 - 6 de 6
- Computed tomography of the paranasal sinuses in the preoperative evaluation of candidates for endonasal surgery(2019) GEBRIM, Eloisa Maria Santiago
bookPart Imagine(2019) CHAMMAS, Maria Cristina; GEBRIM, Eloisa Maria Mello Santiago; LEITE, Claudia da Costa- State-dependent changes in the upper airway assessed by multidetector CT in healthy individuals and during obstructive events in patients with sleep apnea(2019) PASSOS, Ula Lindoso; GENTA, Pedro Rodrigues; MARCONDES, Bianca Fernandes; LORENZI-FILHO, Geraldo; GEBRIM, Eloisa Maria Mello SantiagoObjective: To determine whether airway narrowing during obstructive events occurs predominantly at the retropalatal level and results from dynamic changes in the lateral pharyngeal walls and in tongue position. Methods: We evaluated 11 patients with severe obstructive sleep apnea (OSA) and 7 healthy controls without OSA during wakefulness and during natural sleep (documented by full polysomnography). Using fast multidetector CT, we obtained images of the upper airway in the waking and sleep states. Results: Upper airway narrowing during sleep was significantly greater at the retropalatal level than at the retroglossal level in the OSA group (p < 0.001) and in the control group (p < 0.05). The retropalatal airway volume was smaller in the OSA group than in the control group during wakefulness (p < 0.05) and decreased significantly from wakefulness to sleep only among the OSA group subjects. Retropalatal pharyngeal narrowing was attributed to reductions in the anteroposterior diameter (p = 0.001) and lateral diameter (p = 0.006), which correlated with an increase in lateral pharyngeal wall volume (p = 0.001) and posterior displacement of the tongue (p = 0.001), respectively. Retroglossal pharyngeal narrowing during sleep did not occur in the OSA group subjects. Conclusions: In patients with OSA, upper airway narrowing during sleep occurs predominantly at the retropalatal level, affecting the anteroposterior and lateral dimensions, being associated with lateral pharyngeal wall enlargement and posterior tongue displacement.
bookPart Cabeça e pescoço(2019) MORENO, Raquel Andrade; FAJARDO, Laís; SARPI, Maíra de Oliveira; OLIVETTI, Bruno Casola; MURAKOSHI, Rodrigo Watanabe; TOYAMA, Carlos; GOMES, Regina Lúcia Elia; GARCIA, Márcio Ricardo Taveira; GEBRIM, Eloisa Maria Mello Santiago- Organ doses evaluation for chest computed tomography procedures with TL dosimeters: Comparison with Monte Carlo simulations(2019) GIANSANTE, Louise; MARTINS, Juliana C.; NERSISSIAN, Denise Y.; KIERS, Karen C.; KAY, Fernando U.; SAWAMURA, Marcia V. Y.; LEE, Choonsik; GEBRIM, Eloisa M. M. S.; COSTA, Paulo R.Purpose: To evaluate organ doses in routine and low-dose chest computed tomography (CT) protocols using an experimental methodology. To compare experimental results with results obtained by the National Cancer Institute dosimetry system for CT (NCICT) organ dose calculator. To address the differences on organ dose measurements using tube current modulation (TCM) and fixed tube current protocols. Methods: An experimental approach to evaluate organ doses in pediatric and adult anthropomorphic phantoms using thermoluminescent dosimeters (TLDs) was employed in this study. Several analyses were performed in order to establish the best way to achieve the main results in this investigation. The protocols used in this study were selected after an analysis of patient data collected from the Institute of Radiology of the School of Medicine of the University of Sao Paulo (InRad). The image quality was evaluated by a radiologist from this institution. Six chest adult protocols and four chest pediatric protocols were evaluated. Lung doses were evaluated for the adult phantom and lung and thyroid doses were evaluated for the pediatric phantom. The irradiations were performed using both a GE and a Philips CT scanner. Finally, organ doses measured with dosimeters were compared with Monte Carlo simulations performed with NCICT. Results: After analyzing the data collected from all CT examinations performed during a period of 3 yr, the authors identified that adult and pediatric chest CT are among the most applied protocol in patients in that clinical institution, demonstrating the relevance on evaluating organ doses due to these examinations. With regards to the scan parameters adopted, the authors identified that using 80 kV instead of 120 kV for a pediatric chest routine CT, with TCM in both situations, can lead up to a 28.7% decrease on the absorbed dose. Moreover, in comparison to the standard adult protocol, which is performed with fixed mAs, TCM, and ultra low- dose protocols resulted in dose reductions of up to 35.0% and 90.0%, respectively. Finally, the percent differences found between experimental and Monte Carlo simulated organ doses were within a 20% interval. Conclusions: The results obtained in this study measured the impact on the absorbed dose in routine chest CT by changing several scan parameters while the image quality could be potentially preserved.
bookPart Tomografia computadorizada(2019) CARNEIRO, Hugo Costa; SILVA, Pedro Henrique Ramos Quintino da; MORENO, Raquel Andrade; ZANETTA, Vitor Chiarini; TAKAHASHI, Marcelo Straus; SUZUKI, Lisa; GEBRIM, Eloisa Maria Mello Santiago