RICHARD LOUIS VOEGELS
Projetos de Pesquisa
Unidades Organizacionais
Departamento de Otorrinolaringologia e Oftalmologia, Faculdade de Medicina - Docente
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/32 - Laboratório de Otorrinolaringologia, Hospital das Clínicas, Faculdade de Medicina - Líder
Instituto Central, Hospital das Clínicas, Faculdade de Medicina - Médico
LIM/32 - Laboratório de Otorrinolaringologia, Hospital das Clínicas, Faculdade de Medicina - Líder
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- Endoscopic Study of Ethmoidal Canals in Cadavers, Including a Histological Analysis of Their Contents(2024) FELIPPU, Alexandre Wady Debes; MORSCH, Thiago Picolli; FELIPPU, Andre Wady Debes; CASCIO, Filippo; OLIVEIRA, Claudia Regina Gomes Cardim Mendes de; FELIPPU, Alexandre; VOEGELS, Richard LouisIntroduction The advent of the endoscope has enabled the use of the endonasal approach for a variety of diseases. Studying the ethmoidal canals is important for surgeries of the paranasal sinuses and the anterior base of the skull.Objective To investigate the ethmoidal canals and evaluate their structure, the presence of vessels and nerves, their location, and to perform an anatomopathological study of their contents.Methods We evaluated 20 cadavers (20 left and 20 right nasal cavities) through endoscopic dissection of the anterior base of the skull and exposure of the medial periorbita and dura mater; then, the ethmoidal canals were located and measured in relation to the anterior wall of the sphenoid sinus and between the ethmoidal canals, followed by removal of their content for histological analysis.Results Vessels were present in 75% of the left anterior ethmoidal canals, 70% of the left posterior ethmoidal canals, 75% of the left middle ethmoidal canals, 85% of the right anterior ethmoid canals, and 64.5% of the right posterior ethmoid canals; 50% of the right middle ethmoidal canals contained one vessel.Conclusion The ethmoidal canal does not necessarily contain an ethmoidal artery. Studies with a larger sample should be performed to quantify the correct proportion of arteries and ethmoidal canals.
- Endonasal Identification of the Orbital Apex(2016) TEPEDINO, Miguel S.; PINHEIRO-NETO, Carlos D.; BEZERRA, Thiago F. P.; GARDNER, Paul A.; SNYDERMAN, Carl H.; VOEGELS, Richard L.Objectives/Hypothesis: To describe anatomical landmarks for endoscopic endonasal approaches to the orbital apex and to measure the distances between those landmarks. Methods: In this anatomic study, the nasal fossae of 30 adult fresh cadavers were dissected (n=60 half-skulls). One double-injected orbit was carefully dissected, mainly focusing on the neurovascular structures. The orbital apex was dissected under endoscopic endonasal visualization in all cases. The distances between the ethmoidal crest and choanal arch to the optic canal (OC) and superior orbital fissure (SOF) were measured and recorded. Results: The sample was predominantly male (63.3%, 19/30 cadavers). The following correlations between measurements according to side were observed: ethmoidal crest to OC, r=0.748 (P=0.0001); ethmoidal crest to SOF, r=0.785 (P=0.0001); choanal arch to OC, r=0.835 (P=0.0001); choanal arch to SOF, r=0.820 (P=0.0001). Conclusions: In the cadavers studied in this sample, the ethmoidal crest and choanal arch were relevant structures and exhibited consistent measurements. Spearman correlation coefficients were greater than 0.7, which is indicative of good correlation between measurements obtained in the skull halves of each cadaver. Comparison of the measurements obtained in different sides showed similar values, with no statistically significant differences in the distances between any of the proposed anatomic landmarks.
- Juvenile angiofibroma: major and minor complications of preoperative embolization(2012) OGAWA, Alex Itar; FORNAZIERI, Marco Aurelio; SILVA, Leonardo Victor Espana Rueda da; PINNA, Fabio de Rezende; VOEGELS, Richard Louis; SENNES, Luis Ubirajara; PUGLIA JUNIOR, Paulo; CALDAS, Jose Guilherme Mendes PereiraIntroduction: Juvenile angiofibromas (JA) are highly vascular, benign tumours for which surgery is the treatment of choice. In most services, embolisation is performed prior to resection. Nevertheless, there are few data on the complications of preoperative embolisation for JA. Aim: To describe major and minor complications of preoperative embolisation in a 32-year experience of patients undergoing surgical resection of JA at a tertiary hospital. Methods: Retrospective chart review study of 170 patients who underwent surgical resection of JA at a tertiary hospital between September 1976 and July 2008. Results: All patients were male. Age ranged from 9 to 26 years. Ninety-one patients had no complications after embolisation. Overall, 105 complication events occurred of which four major and 101 minor. Conclusion: In our series, preoperative embolisation for JA produced no irreversible complications and no aesthetic or functional sequelae. The vast majority of complications were transient and amenable to clinical management.
- Sensitivity of nasal airflow variables computed via computational fluid dynamics to the computed tomography segmentation threshold(2018) CHEROBIN, Giancarlo B.; VOEGELS, Richard L.; GEBRIM, Eloise M. M. S.; GARCIA, Guilherme J. M.Computational fluid dynamics (CFD) allows quantitative assessment of transport phenomena in the human nasal cavity, including heat exchange, moisture transport, odorant uptake in the olfactory cleft, and regional delivery of pharmaceutical aerosols. The first step when applying CFD to investigate nasal airflow is to create a 3-dimensional reconstruction of the nasal anatomy from computed tomography (CT) scans or magnetic resonance images (MRI). However, a method to identify the exact location of the air-tissue boundary from CT scans or MRI is currently lacking. This introduces some uncertainty in the nasal cavity geometry. The radiodensity threshold for segmentation of the nasal airways has received little attention in the CFD literature. The goal of this study is to quantify how uncertainty in the segmentation threshold impacts CFD simulations of transport phenomena in the human nasal cavity. Three patients with nasal airway obstruction were included in the analysis. Pre-surgery CT scans were obtained after mucosal decongestion with oxymetazoline. For each patient, the nasal anatomy was reconstructed using three different thresholds in Hounsfield units (-800HU, -550HU, and -300HU). Our results demonstrate that some CFD variables (pressure drop, flowrate, airflow resistance) and anatomic variables (airspace cross-sectional area and volume) are strongly dependent on the segmentation threshold, while other CFD variables (intranasal flow distribution, surface area) are less sensitive to the segmentation threshold. These findings suggest that identification of an optimal threshold for segmentation of the nasal airway from CT scans will be important for good agreement between in vivo measurements and patient-specific CFD simulations of transport phenomena in the nasal cavity, particularly for processes sensitive to the transnasal pressure drop. We recommend that future CFD studies should always report the segmentation threshold used to reconstruct the nasal anatomy.
- Rhinomanometry Versus Computational Fluid Dynamics: Correlated, but Different Techniques(2021) CHEROBIN, Giancarlo B.; VOEGELS, Richard L.; PINNA, Fabio R.; GEBRIM, Eloisa M. M. S.; BAILEY, Ryan S.; GARCIA, Guilherme J. M.Background Past studies reported a low correlation between rhinomanometry and computational fluid dynamics (CFD), but the source of the discrepancy was unclear. Low correlation or lack of correlation has also been reported between subjective and objective measures of nasal patency. Objective: This study investigates (1) the correlation and agreement between nasal resistance derived from CFD (R-CFD) and rhinomanometry (R-RMN), and (2) the correlation between objective and subjective measures of nasal patency. Methods Twenty-five patients with nasal obstruction underwent anterior rhinomanometry before and after mucosal decongestion with oxymetazoline. Subjective nasal patency was assessed with a 0-10 visual analog scale (VAS). CFD simulations were performed based on computed tomography scans obtained after mucosal decongestion. To validate the CFD methods, nasal resistance was measuredin vitro(R-EXPERIMENT) by performing pressure-flow experiments in anatomically accurate plastic nasal replicas from 6 individuals. Results Mucosal decongestion was associated with a reduction in bilateral nasal resistance (0.34 +/- 0.23 Pa.s/ml to 0.19 +/- 0.24 Pa.s/ml, p = 0.003) and improved sensation of nasal airflow (bilateral VAS decreased from 5.2 +/- 1.9 to 2.6 +/- 1.9, p < 0.001). A statistically significant correlation was found between VAS in the most obstructed cavity and unilateral airflow before and after mucosal decongestion (r = -0.42, p = 0.003). Excellent correlation was found between R(CFD)and R-EXPERIMENT(r = 0.96, p < 0.001) with good agreement between the numerical andin vitrovalues (R-CFD/R-EXPERIMENT = 0.93 +/- 0.08). A weak correlation was found between R(CFD)and R-RMN(r = 0.41, p = 0.003) with CFD underpredicting nasal resistance derived from rhinomanometry (R-CFD/R-RMN = 0.65 +/- 0.63). A stronger correlation was found when unilateral airflow at a pressure drop of 75 Pa was used to compare CFD with rhinomanometry (r = 0.76, p < 0.001). Conclusion CFD and rhinomanometry are moderately correlated, but CFD underpredicts nasal resistance measuredin vivodue in part to the assumption of rigid nasal walls. Our results confirm previous reports that subjective nasal patency correlates better with unilateral than with bilateral measurements and in the context of an intervention.
- Biofilms in Chronic Rhinosinusitis with Nasal Polyps(2011) BEZERRA, Thiago Freire Pinto; PADUA, Francini Grecco de Melo; GEBRIM, Eloisa Maria Mello Santiago; SALDIVA, Paulo Hilario Nascimento; VOEGELS, Richard LouisObjective. (1) Evaluate the presence of biofilms in patients with chronic sinusitis with nasal polyps (CRSwNP) and (2) investigate the association of biofilm presence and CRSwNP. Study Design. Cross-sectional study. Setting. University-based tertiary care center. Subjects and Methods. The study group consisted of 33 consecutive patients undergoing functional endoscopic sinus surgery for CRSwNP. The control group consisted of 27 control patients undergoing septoplasty for nasal obstruction without diagnosis of chronic sinusitis. Mucosal samples were harvested intraoperatively for scanning electron microscopic examination to determine biofilm presence. Statistical analysis was performed. For all statistical tests, P = .05 was considered significant. Results. Biofilms were found in 24 (72.7%) of the 33 patients with CRSwNP and in 13 (48.1%) of the 27 septoplasty patients (odds ratio = 2.87; 95% confidence interval, 0.98-8.42; P = .051). Conclusion. (1) Biofilms were present in patients undergoing functional endoscopic sinus surgery for CRSwNP and also in controls without chronic sinusitis. This suggests that biofilms may not be sufficient to cause chronic sinusitis without other cofactors. Host factors could be the responsible for the pathogenesis of biofilms. (2) Although the prevalence of biofilms in patients with CRSwNP was not significantly different from that in the controls, the extremely wide 95% confidence interval, which is just below unity, suggests that a meaningful clinical difference may have been missed because of low statistical power. Further studies are necessary.
- The efficacy of functional endoscopic sinus surgery in the evolution of fever of unknown origin in ICU patients(2011) PADUA, Francini G. M.; BEZERRA, Thiago F. P.; VOEGELS, Richard L.; BENTO, Ricardo F.Conclusion: Functional endoscopic sinus surgery (FESS) was found to be effective in treating fever of unknown origin (FUO) in intensive care unit (ICU) patients with rhinosinusitis, with 62% of patients showing improvement within 5 days of the procedure. Objective: To correlate improvement in FUO with FESS drainage of the paranasal sinuses. Methods: Fifty patients that developed FUO during ICU stay, with CT findings suggestive of rhinosinusitis, and showed no improvement in fever after clinical treatment underwent FESS for drainage of the paranasal sinuses and were evaluated for postoperative improvement of fever. Results: The study sample consisted of 50 patients (74% of whom were male, mean age 48.1 years). The most frequent diagnoses at ICU admission were tetanus, pulmonary disease, and cardiovascular disease. In all, 68% of patients underwent nasogastric or enteral intubation. CT scanning most commonly showed involvement of the sphenoid sinus. In 54% of cases, sinusitis was bilateral and extended throughout the maxillary, ethmoidal, and sphenoidal sinuses. Sinusectomy was performed in all patients, and pathological secretion in the paranasal sinuses was seen in 52% of patients during surgery. Gram-negative bacteria were the most commonly isolated organisms, followed by Gram-positive bacteria and fungi. Improvement of fever was found in 82% of patients after FESS; 38% of these improved within the first 48 h post-procedure, and the remaining 62% within the first 5 postoperative days.
- Complications in the endoscopic and endoscopic-assisted treatment of juvenile nasopharyngeal angiofibroma with intracranial extension(2014) GODOY, Maria Dantas Costa Lima; BEZERRA, Thiago Freire Pinto; PINNA, Fabio de Rezende; VOEGELS, Richard LouisIntroduction: Although it is a rare neoplasm, juvenile nasopharyngeal angiofibroma (JNA) is associated with high rates of morbidity and mortality, with the potential for intracranial extension. Surgical excision is the main treatment. The external approach has largely been replaced by the endoscopic approach in small lesions, and it can be used as a complement in more advanced cases. However, there is no consensus in the literature regarding the complications of surgical treatment of JNAs with intracranial extension. Aim: To assess the prevalence of complications in endoscopic or endoscopic-assisted surgical treatment of JNA with minimal intracranial invasion. Methods: This was a retrospective cohort study of all patients with JNA with intracranial extension (Radkowski grade IIIa) treated with endoscopic, endoscopic-assisted, and external surgery from January of 1996 to May of 2010. Results: Thirteen patients underwent surgery. Endoscopic surgery was performed in three patients, without postoperative complications; endoscopic-assisted surgery in three others, with two instances of complications, and external surgery in seven. Conclusions: Operative treatment of nasopharyngeal angiofibroma with intracranial extension is one of the major challenges of ENT and neurosurgical practice. The success rates and low intra- and postoperative complication rates of endoscopic surgery suggest that this route has been gaining ground in the management of Radkowski grade IIIa JNAs.
- Lateral sphenoid sinus recess cerebrospinal fluid leak: a case series(2014) MELO, Nelson Almeida d'Avila; BORGES, Bruno Barros Pinto; MAGLIARELLI FILHO, Pedro Augusto; GODOY, Maria Dantas Costa Lima; PEREIRA, Larissa Vilela; PINNA, Fabio de Rezende; VOEGELS, Richard LouisThe lateral recess of the sphenoid sinus is one of the most common sites of meningocele and spontaneous cerebrospinal fluid (CSF) leak. Despite the availability of several techniques for closure of skull base defects occurring in this location, recurrence still poses a major challenge. This report reviews the experience of surgical repair of lateral sphenoid sinus recess CSF leak at a tertiary referral center and provides a brief discussion of this rare lesion. Nine surgeries were performed for six cases of spontaneous lateral sphenoid sinus recess CSF leak (two revisions and one repair of a new defect). Two patients presented with intracranial hypertension (ICH) and four with meningocele or meningoencephalocele. The transpterygoid approach was used in two procedures. A multilayer graft was used in seven cases and a nasoseptal flap in two. Three patients received lumbar or ventricular shunts, and one received acetazolamide for ICH management. Two minor complications were recorded, and the overall surgical success rate was 78 %. We conclude that nasoseptal flaps are a valid option for repair of recurrent CSF leaks, particularly in the lateral sphenoid sinus recess. Furthermore, identification and correction of ICH plays an essential role in the success of treatment in this patient population.