RESUMEN
BACKGROUND: Changes of nasal dimensions can influence the air-conditioning capacity of the nose because of alterations of airflow patterns. The goal of this study was to evaluate the correlation between intranasal temperature and humidity values and nasal dimensions, assessed by means of acoustic rhinometry. METHODS: Eighty healthy volunteers (40 men and 40 women; median age, 51 years; range, 20-84 years) were enrolled in the study. In total, 160 nasal cavities were examined. All volunteers underwent a standardized acoustic rhinometry. Additionally, intranasal air temperature and humidity measurements at defined intranasal detection sites within the anterior nasal segment were performed. RESULTS: There was no statistically significant difference between the right and left side of the nose regarding air temperature, absolute humidity, and acoustic rhinometric values. A negative correlation was established between the rhinometric nasal volumes/minimal cross-sectional areas and air temperature and absolute humidity values at the three intranasal detection sites. CONCLUSION: According to our results, nasal volumes and cross- sectional areas relevantly influence nasal air conditioning. A healthy nasal cavity with smaller volumes and cross-sectional areas seems to present a more effective air-conditioning function than a too "wide" open nose because of changes in airflow patterns. This observation should be considered as a limitation for overly extensive nasal surgery especially of the turbinates.
Asunto(s)
Aire/análisis , Cavidad Nasal/fisiopatología , Ventilación Pulmonar , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Humedad , Masculino , Persona de Mediana Edad , Cavidad Nasal/química , Cavidad Nasal/patología , Tamaño de los Órganos , Rinometría Acústica , TemperaturaRESUMEN
BACKGROUND: Nasal obstruction is a typical symptom in patients with nasal septal perforations. Rhinomanometry and acoustic rhinometry are not reliable in these cases because the perforations generate incorrect results. Infrared thermography camera (ITC) systems allow contact-free intranasal recordings of the nasal surface temperature and the semiquantification of nasal airflow. The aim of this study was to perform contact-free temperature measurements of the nasal vestibular surface by application of ITC systems in patients with septal perforations to investigate the disturbed intranasal heat exchange and nasal airflow. METHODS: The surface temperature profiles within the nasal vestibules of healthy volunteers (n=10) and patients with septal perforations (n=3) were recorded with an ITC during several breathing cycles. Thermal images were taken (60/s) displaying the surface temperature in degrees centigrade corresponding to a color scale. RESULTS: The temperature recordings showed a disturbed intranasal heat exchange during inspiration and expiration in patients with septal perforations in comparison with healthy subjects. A reduced and irregular inspiratory cooling of the entire surface within the nasal vestibules visualizes a reduced and disturbed airflow volume. CONCLUSION: The study was able to prove the feasibility of intranasal temperature recordings of the surface with an ITC system in patients with septal perforations. Contrary to rhinomanometry and acoustic rhinometry, thermography cameras can be applied to examine airflow in patients with septal perforations. The detected reduced cooling of the surface during inspiration might be a possible explanation for the patients' feelings of nasal obstruction.
Asunto(s)
Epistaxis/diagnóstico , Obstrucción Nasal/diagnóstico , Tabique Nasal/patología , Adulto , Anciano , Epistaxis/patología , Epistaxis/fisiopatología , Estudios de Factibilidad , Femenino , Humanos , Rayos Infrarrojos , Masculino , Persona de Mediana Edad , Obstrucción Nasal/patología , Obstrucción Nasal/fisiopatología , Termografía/instrumentación , Termografía/métodosRESUMEN
BACKGROUND: Changes in nasal airflow caused by varying intranasal volumes and cross-sectional areas affect the contact between air and surrounding mucosa entailing alterations in nasal air conditioning. This study evaluates the correlation between nasal air conditioning and the volumes of the inferior and middle turbinates as measured by magnetic resonance imaging (MRI). METHODS: Fourteen healthy volunteers were enrolled. Each volunteer had been examined by rhinomanometry, acoustic rhinometry, intranasal air temperature, and humidity measurements at defined intranasal sites as well as MRI of the nasal cavity and the paranasal sinuses. The volumetric data of the turbinates was based on the volumetric software Amira. RESULTS: Comparable results were obtained regarding absolute humidity values and temperature values within the nasal valve area and middle turbinate area for both the right and the left side of the nasal cavity. No statistically significant differences were found in the rhinomanometric values and the acoustic rhinometry results of both sides (p > 0.05). No statistical correlations were found between the volumes of the inferior (mean, 6.1 cm3) and middle turbinate (mean, 1.8 cm3) and the corresponding humidity and temperature values. Additionally, the air temperature and humidity values did not correlate with the rhinometrical endonasal volumes (0-20 mm and 20-50 mm from the nasal entrance). CONCLUSION: The normal range of volumes of the inferior and middle turbinate does not seem to have a significant impact on intranasal air conditioning in healthy subjects. The exact limits where alterations of the turbinate volume negatively affect nasal air conditioning are still unknown.
Asunto(s)
Imagen por Resonancia Magnética/métodos , Cavidad Nasal/fisiología , Cornetes Nasales/anatomía & histología , Adulto , Anciano , Femenino , Humanos , Humedad , Masculino , Persona de Mediana Edad , TemperaturaRESUMEN
OBJECTIVE: The surface temperature distribution within the nasal vestibule and the nasal cavity strongly depends on the exact intranasal detection site and point of time during the respiratory cycle. Therefore, conventional temperature measurements e.g. with thermocouples only provide selective measurements. The use of infrared thermography cameras could present a new contactless method with a high spatiotemporal resolution. The aim of the present study was to evaluate the use of infrared thermography camera systems for measurements of the nasal surface temperature during respiration. METHODS: The surface temperature profiles within the nasal vestibules of healthy volunteers were recorded with infrared thermography cameras during several breathing cycles. Two different types of infrared thermography standard systems were used. RESULTS: The recordings allowed a display of temperature alterations within the nasal vestibules in a high spatiotemporal resolution synchronous to the breathing cycle. During inspiration, the vestibular surface cooled down presenting a non-homogenous distribution (range, 24.7 to 30.2 degrees C). During expiration, the vestibular surface was warmed again with a non-homogenous distribution (range, 33.1 to 36.2 degrees C). The results of both camera systems were comparable. CONCLUSION: Infrared thermography cameras allow the exact mapping of nasal surface temperature within the nasal vestibules with a high spatiotemporal resolution without surface contact.
Asunto(s)
Procesamiento de Imagen Asistido por Computador/instrumentación , Cavidad Nasal , Fotograbar/instrumentación , Respiración , Termogénesis/fisiología , Termografía/métodos , Estudios de Factibilidad , Humanos , Reproducibilidad de los Resultados , Termografía/instrumentaciónRESUMEN
BACKGROUND: The anterior nasal segment is the most effective part of the nasal airways when it comes to warming and humidification of the inhaled air. Any changes in nasal geometry in this segment modifying the airflow could therefore affect nasal air conditioning. The goal of this study was to examine if external nasal strips have an influence on intranasal geometry and air-conditioning. METHODS: Twenty healthy volunteers (mean age, 36 years) were enrolled in the study. All volunteers received active anterior rhinomanometry and acoustic rhinometry before and while wearing commercially available external nasal strips. In addition, in vivo air temperature and humidity were measured with and without nasal strips at the defined intranasal sites. RESULTS: No statistically significant changes in temperature, humidity, and rhinomanometric values were detected during the use of nasal strips (p > 0.05). The statistical analysis of the acoustic rhinometric results showed a significant increase (p < 0.05) in the minimal cross-sectional areas (MCA) 1 (0-2 cm) and MCA2 (2-5 cm) and the nasal volume (Vol) 1 (0-2 cm). On the other hand, the nasal strips did not significantly alter the nasal Vol2 (2-5 cm; p > 0.05). CONCLUSION: Changes in the nasal geometry of the anterior part of the nose by wearing nasal strips did not relevantly alter intranasal air-conditioning. The application of nasal strips entails an increase in MCAs but not in nasal airflow Vol.
Asunto(s)
Resistencia de las Vías Respiratorias/fisiología , Temperatura Corporal/fisiología , Humedad , Cavidad Nasal/anatomía & histología , Cavidad Nasal/fisiología , Adulto , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valores de Referencia , Rinomanometría , Rinometría Acústica/métodosRESUMEN
BACKGROUND: Too extensive resection of the inferior turbinates (ITs) during nasal surgery leads to a severely disturbed intranasal air conditioning. Data comparing nasal air conditioning before and after turbinoplasty in nasal surgery are still lacking. The aim of this study was to determine the early effect of bilateral turbinoplasty combined with septoplasty on intranasal heating and humidification. METHODS: Twelve patients were included into this prospective study. In one-half of the patients a bilateral turbinoplasty of the IT during nasal surgery was performed, in the other half no surgery on the IT was performed. Intranasal air temperature and humidity were measured before and after surgery. A combined miniaturized thermocouple and a humidity sensor were used for simultaneous in vivo intranasal measurements. RESULTS: There were no statistically significant differences in temperature and humidity values between the two study groups before surgery (p > 0.05). In both groups, the postoperative temperature and humidity values were statistically significantly higher compared with the preoperative ones (p < 0.05). Regarding the two patient groups, the postoperative increase in temperature and humidity was even more pronounced in patients undergoing additional bilateral turbinoplasty. CONCLUSION: According to the results of this study, patients seemed to overall benefit from nasal surgery, with and without a preserving bilateral turbinoplasty, because intranasal air conditioning was improved after surgery. A carefully performed and conservative reduction of the IT in nasal surgery seems to even improve intranasal air conditioning.
Asunto(s)
Cavidad Nasal/fisiología , Obstrucción Nasal/cirugía , Tabique Nasal/cirugía , Procedimientos Quirúrgicos Otorrinolaringológicos/métodos , Procedimientos de Cirugía Plástica/métodos , Cornetes Nasales/cirugía , Adolescente , Adulto , Aire , Femenino , Estudios de Seguimiento , Humanos , Humedad , Masculino , Persona de Mediana Edad , Obstrucción Nasal/fisiopatología , Estudios Prospectivos , Temperatura , Factores de Tiempo , Resultado del TratamientoRESUMEN
BACKGROUND: Menthol is a natural herbal compound. Its isomer l-menthol presents the characteristic peppermint scent and is also responsible for the cooling sensation when applied to nasal mucosal surfaces because of stimulation of trigeminal cold receptors. The aim of this study was to assess the effect of menthol inhalation on end-inspiratory nasal mucosa temperature and nasal patency. METHODS: Eighteen healthy volunteers with a mean age of 30 years were enrolled in this study. Objective measurements included the septal mucosal temperature within the nasal valve area by using a miniaturized thermocouple as well as active anterior rhinomanometry before and after inhalation of l-menthol vapor. All subjects completed a visual analog scale (VAS; range, 1-10) evaluating nasal patency before and after menthol. RESULTS: The mean end-inspiratory mucosal temperature ranged from 27.7 degrees C (+/-4.0) before menthol inhalation to 28.5 degrees C (+/-3.5) after menthol inhalation. There were no statistically significant differences between the temperature values before and after menthol inhalation (p > 0.05). In addition, no statistically significant differences between the rhinomanometric values before and after menthol inhalation were observed. Sixteen of the 18 subjects reported an improvement of nasal breathing after menthol inhalation by means of the VAS. CONCLUSION: Menthol inhalation does not have an effect on nasal mucosal temperature and nasal airflow. The subjective impression of an improved nasal airflow supports the fact that menthol leads to a direct stimulation of cold receptors modulating the cool sensation, entailing the subjective feeling of a clear and wide nose.
Asunto(s)
Resistencia de las Vías Respiratorias/fisiología , Temperatura Corporal/efectos de los fármacos , Mentol/administración & dosificación , Mucosa Nasal/fisiología , Administración por Inhalación , Adulto , Resistencia de las Vías Respiratorias/efectos de los fármacos , Antipruriginosos/administración & dosificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Mucosa Nasal/efectos de los fármacos , Rinomanometría , Sensación/efectos de los fármacosRESUMEN
OBJECTIVES/HYPOTHESIS: Elderly patients frequently complain about the feeling of a dry nose and recurrent crusting probably due to age-related degenerative effects of the nasal mucosa. Data on intranasal air conditioning in elderly patients are missing. The aim of the study was to compare intranasal heating and humidification of respiratory air in elderly subjects and a younger control group. Additionally, rhinomanometrical and rhinometrical data were examined. STUDY DESIGN: The study was conceived as randomized, prospective study. METHODS: Forty study subjects (median age, 70 years; range, 61-84) and 40 control subjects (median age, 27 years; range, 20-40) were included in the study. In vivo air temperature and humidity values were simultaneously measured at defined intranasal sites. Active anterior rhinomanometry and acoustic rhinometry also were performed in every subject. RESULTS: In the study group, the median end-inspiratory air temperature (degrees C)/absolute humidity (g/m3) values were 24.0 degrees C/13.8 g/m3 within the nasal valve region and 24.3 degrees C/14.7 g/m3 anterior to the head of the middle turbinate. In the control group, the corresponding values were 27.0 degrees C/15.5 g/m3 and 26.7 degrees C/17.0 g/m3. Temperature and humidity values were significantly lower in the study group (P < .05). The minimal cross-sectional areas and volumes were significantly higher in the study group (P < .05). CONCLUSIONS: Nasal complaints in elderly patients are a consequence of lower intranasal air temperature and humidity values combined with relatively enlarged nasal cavities due to involution atrophy of the nasal mucosa.
Asunto(s)
Envejecimiento/fisiología , Inhalación/fisiología , Cavidad Nasal/fisiología , Mucosa Nasal/fisiología , Intercambio Gaseoso Pulmonar/fisiología , Adulto , Anciano , Anciano de 80 o más Años , Femenino , Humanos , Humedad , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Recurrencia , Rinometría AcústicaRESUMEN
BACKGROUND: The aim of this study was to measure in vivo nasal mucosal temperature and assess its relationship to nasal patency. METHODS: Nasal mucosal temperature of 30 nasal cavities was measured by means of a miniaturized thermocouple within the anterior turbinate area during respiration. Temperature values were compared with corresponding rhinomanometrical data. RESULTS: The median mucosal temperature ranged from 30.2 degrees C (range, 28.9-31.7 degrees C) after inspiration to 32.2 degrees C (range, 31.0-33.9 degrees C) after expiration. The end-inspiratory (r = -0.85) and end-expiratory mucosal temperature values (r = -0.88) negatively correlated with the rhinomanometrical data. CONCLUSION: This study supports the fact that there is a negative correlation between nasal mucosal temperature and nasal resistance. Changes in nasal patency seem to influence nasal mucosal temperature. Within this context, nasal thermoreceptors might play an important role concerning the perception of nasal patency.
Asunto(s)
Temperatura Corporal/fisiología , Cavidad Nasal/fisiología , Mucosa Nasal/fisiología , Ventilación Pulmonar/fisiología , Rinomanometría/métodos , Adolescente , Adulto , Femenino , Estudios de Seguimiento , Humanos , Inhalación/fisiología , Masculino , Valores de ReferenciaRESUMEN
Nasal cavity volume and blood temperature along the nasal airways, reflecting the mucosal temperature, are considered to be the most important predictors of nasal air conditioning. The purpose of this study was to simultaneously in vivo measure intranasal air as well as mucosal temperature for the first time. Fifteen healthy subjects were enrolled into the study. Two combined miniaturized thermocouples were used for simultaneous recording of intranasal air and mucosal temperature within the anterior turbinate area close to the head of the middle turbinate without interruption of nasal breathing. The highest air and mucosal temperature values were detected at the end of expiration, the lowest values at the end of inspiration. The difference was statistically significant (P < 0.05). The mean mucosal temperature ranged from 30.2 +/- 0.9 to 32.2 +/- 0.8 degrees C. The mean air temperature ranged from 28.5 +/- 1.2 to 34.1 +/- 0.7 degrees C. The mean differences between air and mucosal temperature were 1.7 +/- 0.5 degrees C after inspiration and 1.9 +/- 0.7 degrees C after expiration. Simultaneous measurements of intranasal air and mucosal temperature are practicable. The detected temperature gradient between air and mucosa confirm a relevant heat exchange during inspiration and expiration. This gradient between air and mucosa is obligatory for heat and water exchange to ensure adequate nasal air conditioning.
Asunto(s)
Aire , Regulación de la Temperatura Corporal/fisiología , Temperatura Corporal , Mucosa Nasal/fisiología , Adolescente , Adulto , Femenino , Humanos , Humedad , Masculino , Respiración , Estadísticas no ParamétricasRESUMEN
BACKGROUND: The goal of this study was to investigate the effect of nasal sponges on the subjective nasal well-being after nasal and sinus surgery. METHODS: The study was designed as a randomized prospective clinical trial comparing four different types of sponges used as nasal passive humidifiers (NPHs). The 40 participants were blinded to the size and pore structure of the NPHs. The NPHs were applied in both nostrils for 1 hour on the 2nd postoperative day. Subjective nasal sensations were evaluated on a visual analog scale. RESULTS: Wearing comfort was rated as satisfactory. Intranasal humidity and feeling of a dry nose were rated as improved after wearing the NPHs. CONCLUSION: The use of NPHs may have a positive effect on the patients' perception of nasal obstruction and intranasal humidity. Additional investigations in patients with intranasal dryness are planned to improve patients' complaints.
Asunto(s)
Procedimientos Quirúrgicos Otorrinolaringológicos/instrumentación , Adolescente , Adulto , Anciano , Femenino , Humanos , Humedad , Masculino , Persona de Mediana Edad , Obstrucción Nasal , Enfermedades Nasales/terapia , Dimensión del Dolor , Estudios Prospectivos , Rinomanometría , RinoplastiaRESUMEN
Acoustic rhinometry is one method to evaluate nasal geometry by an acoustic reflection technique. The aim of this study was to investigate the changes in acoustic rhinometry after nasal provocation in patients with exclusively perennial allergic rhinitis. In 19 patients, acoustic rhinometry and active anterior rhinomanometry were performed before and after nasal provocation test. There was a statistically significant nasal flow reduction measured by active anterior rhinomanometry after nasal provocation (p < 0.05) and a median symptom score of four points, both indicating a positive response to nasal provocation. On the other hand, there was no statistically significant change in the values of acoustic rhinometry after nasal provocation (p > 0.05). In patients with exclusively perennial allergic rhinitis, acoustic rhinometry does not seem to significantly change after nasal provocation. In contrast, active anterior rhinomanometry values decreased significantly after nasal provocation. The presented results indicate that acoustic rhinometry does not seem to be a diagnostic method superior to active anterior rhinomanometry in this context.
Asunto(s)
Pruebas de Provocación Nasal , Rinitis Alérgica Perenne/fisiopatología , Rinometría Acústica , Adolescente , Adulto , Femenino , Humanos , Inmunoglobulina E/sangre , Masculino , Persona de Mediana Edad , Pruebas Cutáneas , Estadísticas no ParamétricasRESUMEN
OBJECTIVE: Septoplasty is one of the most frequently performed surgical procedures by ear, nose, and throat surgeons. Yet the objective control of success concerning septal surgery still is very difficult and causes controversy. Data concerning one of the main functions of the nose, namely the heating and humidification of inspired air, before and after nasal surgery, are still missing. Therefore, the aim of this study was to compare intranasal air temperature and humidity values before and after septoplasty with bilateral turbinoplasty. METHODS: Sixteen patients were included in this prospective study. Intranasal temperature and humidity were measured in the anterior turbinate area close to the head of the middle turbinate. A miniaturized thermocouple and a humidity sensor were applied for continuous intranasal detection. RESULTS: Significant differences between temperature and humidity values before and after septoplasty could be observed, including absolute temperature, increase in temperature, absolute humidity, and increase in humidity. The postoperative values were significantly higher than the preoperative ones (P < .05). CONCLUSIONS: According to the results of our study, patients seem to profit from septoplasty as heating and humidification as one of the most important nasal functions are restored and even improved after surgery. We therefore conclude that properly performed septoplasty is able to main its importance within the variety of nasal surgical procedures ensuring improved nasal function as well as patient contentment.
Asunto(s)
Cavidad Nasal/fisiología , Tabique Nasal/cirugía , Cornetes Nasales/cirugía , Adolescente , Adulto , Aire , Femenino , Humanos , Humedad , Masculino , Persona de Mediana Edad , Estudios Prospectivos , Procedimientos de Cirugía Plástica , TemperaturaRESUMEN
BACKGROUND: Adequate nasal air-conditioning is of greatest importance. Because detailed processes of nasal air-conditioning still are not completely understood, numerical simulations of intranasal temperature distribution and airflow patterns during inspiration and expiration were performed. METHODS: A three-dimensional model of the human nose based on computed tomography scans was reconstructed. A computational fluid dynamics application was used displaying temperature and airflow during respiration based on time-dependent boundary conditions. RESULTS: Absolute air temperature and velocity values vary depending on detection site and time of detection. Areas of low velocities and turbulence show distinct changes in air temperature. The turbinate areas prove to be the main regions for heat exchange. The numerical results showed excellent comparability to our in vivo measurements. CONCLUSION: Numerical simulation of temperature and airflow based on computational fluid dynamics is feasible providing entirely novel information and an insight into air-conditioning of the human nose.
Asunto(s)
Simulación por Computador , Imagenología Tridimensional , Nariz/fisiología , Análisis Numérico Asistido por Computador , Ventilación Pulmonar , Temperatura , Adulto , Espiración , Humanos , Inhalación , Masculino , Valores de ReferenciaRESUMEN
We would like to present the rare case of a now 37-year old female patient with autosomal-recessively inherited anhidrotic ectodermal dysplasia being treated in our ENT department for atrophic rhinitis. The clinical appearance very much resembled the picture of an "empty nose" with distinct hypoplasia of the turbinates and extensively wide nasal cavities. We want to point out the possible existence of atrophic rhinitis against the background of an underlying syndromatic disease in adults and also the pediatric patient.
Asunto(s)
Displasia Ectodérmica/complicaciones , Rinitis Atrófica/etiología , Adulto , Femenino , Humanos , Rinitis Atrófica/diagnóstico , Rinitis Atrófica/terapiaRESUMEN
PURPOSE: Radical sinus surgery disturbs intranasal humidification and heating of inspired air, resulting in reduced air conditioning mainly caused by a disturbed airflow. Therefore, the aim of this study was to simulate the intranasal airflow after radical sinus surgery during inspiration by means of numerical simulation. MATERIAL AND METHODS: A bilateral model of the human nose with maxillectomy, ethmoidectomy, and resection of the lateral nasal wall and the turbinates on one side based on a multislice computed tomographic scan was reconstructed. An unsteady numerical simulation displaying the intranasal airflow patterns applying the computational fluid dynamics solver Fluent 6.1.22 was performed. RESULTS: Spacious vortices throughout the entire nasal cavity and the paranasal sinuses caused by the radical resections occurred, causing a less-intense contact between air and the surrounding nasal wall. An enlargement of the nasal cavity volume and a reduction of the nasal surface area in ratio to the nasal cavity volume could be observed. CONCLUSIONS: Aggressive sinus surgery leads to disturbed intranasal air conditioning caused by disturbed intranasal airflow patterns and a reduction of the surface area in relation to the nasal volume. The presented numerical simulation demonstrates the close relation between air conditioning and intranasal airflow. It can be helpful to understand and interpret in vivo measured data of intranasal temperature and humidity.
Asunto(s)
Nariz/fisiología , Senos Paranasales/cirugía , Respiración , Fenómenos Biofísicos , Biofisica , Humanos , Humedad , Cavidad Nasal/fisiología , Senos Paranasales/fisiología , Periodo Posoperatorio , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: Radical surgical resection of the turbinates leads to a reduced intranasal air conditioning. The aim of this study was to determine the effect of turbinate resection on intranasal heating and airflow patterns using a numerical simulation. METHODS: A bilateral model of the human nose with resection of the turbinates on one side based on a CT-scan was reconstructed. A numerical simulation applying the computational fluid dynamics (CFD) solver Fluent 6.1.22 was performed displaying inspiratory intranasal air temperature and airflow patterns. RESULTS: Due to resection of the turbinates the airflow pattern is disturbed resulting in a spacious vortex throughout the entire nasal cavity. Hence, contact between air and surrounding nasal wall is less intense. Consequently, intranasal heating of the inspired air is relevantly reduced. CONCLUSIONS: Surgical resection of the turbinates leads to a disturbed intranasal air conditioning. The presented numerical simulation demonstrates the close relation between airflow patterns and heating.
Asunto(s)
Temperatura Corporal , Simulación por Computador , Modelos Anatómicos , Fenómenos Fisiológicos Respiratorios , Cornetes Nasales/cirugía , Cornetes Nasales/fisiologíaRESUMEN
OBJECTIVES/HYPOTHESIS: In vivo measurements of the intranasal air temperature are feasible. The present study was designed to reproduce temperature distributions within the human nasal cavity by means of numerical simulation. STUDY DESIGN: Numerical simulation. METHODS: Based on computed tomography (CT), a steady-state computational fluid dynamics (CFD) simulation was performed displaying the temperature distribution throughout the human nasal cavity during inspiration. The results of the numerical simulation were compared with in vivo temperature measurements. RESULTS: The numerical simulation demonstrated that the major increase of the inspiratory air temperature can be found in the anterior nasal segment, especially within the nasal valve area, which is comparable to in vivo measurements. Intranasal areas of high temperature were characterized by turbulent airflow with vortices of low velocity. The results of numerical simulation showed an excellent comparability to the results of previous in vivo measurements in the entire nasal cavity. CONCLUSION: The anterior nasal segment is the most effective part of the nose in heating of the ambient air. The findings demonstrated the complexity of the relationship between airflow patterns and heating of inspired air. A numerical simulation of the temperature distribution using CFD is practicable.
Asunto(s)
Inhalación/fisiología , Cavidad Nasal/fisiología , Temperatura , Aire , Simulación por Computador , Humanos , Imagenología Tridimensional , Cavidad Nasal/diagnóstico por imagen , Tomografía Computarizada por Rayos XRESUMEN
BACKGROUND: The most typical symptoms of patients with nasal septal perforation (SP) are crusting and recurrent nosebleed. The objective of the study was to determine the influence of SP on intranasal temperature profile and airflow patterns during inspiration by means of numerical simulation. METHODS: Two realistic bilateral models of the human nose with and without SP were reconstructed based on computed tomography (CT). A numerical simulation was performed. The intranasal air temperature distribution and airflow patterns during inspiration were displayed, analyzed, and compared. RESULTS: SP causes a highly disturbed airflow in the area of perforation. A spacious vortex within the perforation including various localized vortices was detected. A disturbed intranasal temperature distribution between the right and left nasal cavities developed. CONCLUSIONS: The numerical simulation demonstrates the interaction between airflow patterns and heating of respiratory air. The disturbed airflow causes reduced air conditioning. This fact may contribute to crusting and recurrent nosebleed.
Asunto(s)
Aire , Simulación por Computador , Imagenología Tridimensional , Inhalación , Tabique Nasal/patología , Temperatura , Humanos , Tomografía Computarizada por Rayos XRESUMEN
With an incidence of less than 0.3 per cent, post-radiation sarcomas are rare malignant neoplasms with a very poor prognosis. On average, they occur after a latency period of at least 15 years following radiation therapy with doses ranging from 24 to 80 Gy. We present the case of a post-irradiation malignant fibrous histiocytoma (MFH) on the floor of the mouth in a 79-year-old male patient arising only five and a half years after radiation therapy. The primary tumour was classified as a well differentiated squamous cell carcinoma of the right rim of the tongue. Primary therapy was surgical resection of the tumour and post-operative radiation with 50 Gy. Five and a half years later, the patient developed a rapidly progressing MFH within the field of radiation.