Medium-term effects of rapid maxillary expansion on nasal cavity and pharyngeal airway volumes considering age as a factor: A retrospective study.

OBJECTIVES: The medium-term effects of rapid maxillary expansion (RME) on nasal cavity (NC) and upper airway (UA) dimensions based on chronological age are still unclear. This retrospective study evaluated the medium-term changes occurring in the NC and pharyngeal airways (PA) after RME in two distinct age-based cohorts of patients. METHODS: This retrospective study included 48 subjects who underwent RME grouped in two cohorts: a 6-9-year-old group (EEG group: early expansion group - 25 subjects) and an 11-14-year-old group (LEG group: late expansion group - 23 subjects). NC and PA volumes were analyzed from CBCT imaging segmentation before RME (T0) and twelve months after RME (T1). The amount of maxillary expansion (PW) and minimal cross-sectional area (CSmin) were also considered. RESULTS: All PAs' volumetric sub-regions, CSmin and PW showed a significant volumetric increment (p < 0.05). Inter-group comparisons showed significant differences (p < 0.05) for nasopharynx and CSmin parameters (p < 0.05), while no significant changes were recorded for the other UA's sub-regions and PW (p > 0.05). According to a deviation analysis, part of the UA increase (more marked for the nasopharynx area) may have occurred due to reduced adenotonsillar tissues, which were larger in the EEG group. CONCLUSIONS: Twelve months after treatment, clinicians should not expect changes in the UAs dimensions to be solely related to treatment effects of RME; instead, normal craniofacial growth changes and spontaneous regression of the adenotonsillar tissue could represent the most significant factors influencing UAs changes. CLINICAL SIGNIFICANCE: From the clinical perspective, the results of the present study encourage caution when considering the therapeutic effects of RME on airways dimensions.

Parameter characteristics in intranasal drug delivery: A key to targeting medications to the olfactory airspace.

BACKGROUND: The nose is a viable pathway for topical drug delivery to the olfactory cleft for treatment of obstructive smell loss and nose-to-brain drug delivery. This study investigates how variations in nasal vestibule morphology influence intranasal spray drug transport to the olfactory cleft and olfactory roof/bulb regions. METHODS: The unilateral nasal vestibule morphology in three healthy subjects with healthy normal nasal anatomy was classified as Elongated (Subject DN001), Notched (Subject DN002), and Standard (Subject DN003). Computational fluid and particle dynamics modelling were used to simulate nasal airflow and drug particle transport to the olfactory cleft and olfactory roof/bulb regions in each subject-specific nasal cavity. To evaluate highest drug depositions in these regions, the particle transport simulations involved extensive parameter combination analyses: 6 inspiratory flow rates mimicking resting to sniffing (10-50 L/min); 5 spray release locations (Top, Bottom, Central, Lateral, and Medial); 5 head positions (Upright, Tilted Forward, Tilted Back, Supine, and Mygind); 3 particle velocities (1, 5, and 10 m/s); 350,000 µm-particles (1-100 µm) and 346,500 nanoparticles (10-990 nm). FINDINGS: Particle size groups with highest depositions in olfactory cleft: DN001 left = 28.4% at 11-20 µm, right = 75.3% at 6-10 µm; DN002 left = 16.8% at 1-5 µm, right = 45.3% at 30-40 nm; DN003 left = 29.1% at 21-30 µm, right = 15.9% at 6-10 µm. Highest depositions in olfactory roof/bulb: DN001 left = 6.5% at 11-20 µm, right = 26.4% at 11-20 µm; DN002 left = 3.6% at 1-5 µm, right = 2.6% at 1-5 µm; DN003 left = 2.8% at 21-30 µm, right = 1.7% at 31-40 µm. INTERPRETATION: DN001 (Elongated nasal vestibule) had the most deposition in the olfactory regions. Micron-particles size groups generally had better deposition in the olfactory regions.

Insights into exercise-induced rhinitis based on nasal aerodynamics induced by airway morphology.

BACKGROUND: Exercise-induced rhinitis (EIR) is a poorly understood phenomenon that may be related to increased inspiratory airflow. Characterization of the development of EIR is important to understand contributing factors. OBJECTIVE: To characterize how different nasal morphologies respond to airflow-related variables during rapid/deep inspiratory conditions. METHODS: Subject-specific nasal airways were reconstructed from radiographic images. Unilateral airways were classified as Standard, Notched, or Elongated accord to their distinct nasal vestibule morphology. Computational fluid dynamics simulations were performed at various airflow rates. RESULTS: For all simulated flow rates, average resistance at the nasal vestibule, airflow velocity and wall sheer stress were highest in Notched. Average mucosal heat flux was highest in Standard. Notched phenotypes showed lower mean percent increases from 10 L/min to 50 L/min in all computed variables. CONCLUSION: Resistance values and airflow velocities depicted a more constricted nasal vestibule in the Notched phenotypes, while perception of nasal mucosal cooling (heat flux) favored the Standard phenotypes. Different nasal phenotypes may predispose to EIR.

Morphological Analysis of the Olfactory System of the Pig-Nosed Turtle, Carettochelys insculpta.

The turtle olfactory organ consists of the upper (UCE) and lower (LCE) chamber epithelium, projecting to the ventral and dorsal parts of the olfactory bulbs, respectively. The UCE is associated with glands, contains ciliated olfactory receptor neurons, and is assumed to detect odorants primarily in air, while the LCE is devoid of glands, contains microvillous olfactory receptor neurons, and is assumed to detect odorants primarily in water. Examining the olfactory system of the pig-nosed turtle, Carettochelys insculpta, this study found that both the upper and lower chambers of the nasal cavity were lined with sensory epithelium devoid of associated glands and contained ciliated olfactory receptor neurons. Moreover, the olfactory bulbs were not divided into dorsal and ventral parts. These results suggest that the olfactory system of the pig-nosed turtle is a single system specialized for detecting odorants in water.

Structure-function relationships in the nasal cavity of Arctic and subtropical seals.

The heating and moistening of inhaled air, and the cooling and moisture removal from exhaled air, are crucial for the survival of animals under severe environmental conditions. Arctic mammals have evolved specific adaptive mechanisms to retain warmth and water and restrict heat loss during breathing. Here, the role of the porous turbinates of the nasal cavities of Arctic and subtropical seals is studied with this in mind. Mass and energy balance equations are used to compute the time-dependent temperature and water vapor profiles along the nasal passage. A quasi-1D model based on computed tomography images of seal nasal cavities is used in numerical simulations. Measured cross-sectional areas of the air channel and the perimeters of the computed tomography slices along the nasal cavities of the two seal species are used. The model includes coupled heat and vapor transfer at the air-mucus interface and heat transfer at the interfaces between the tissues and blood vessels. The model, which assumes constant blood flow to the nose, can be used to predict the temperature of the exhaled air as a function of ambient temperature. The energy dissipation (entropy production) in the nasal passages was used to measure the relative importance of structural parameters for heat and water recovery. We found that an increase in perimeter led to significant decreases in the total energy dissipation. This is explained by improved conditions for heat and water transfer with a larger complexity of turbinates. Owing to differences in their nasal cavity morphology, the Arctic seal is expected to be advantaged in these respects relative to the subtropical seal.

A Systematic Literature Study of the Sinus Septi Nasi, Crista Galli and Other Minor Pneumatizations / Estudio Bibliográfico Sistemático del Seno Septi Nasi, Crista Galli y Otras Neumatizaciones Menores

SUMMARY: Variations in the paranasal sinuses and pneumatizations originating from these structures are clinically important for surgical procedures to be performed in the nose and nasal cavity regions. No systematic review examining the sinus septi nasi, crista galli and other minor pneumatizations was found in the literature review. This study aimed to review the papers in the literature including the sinus septi nasi, crista galli and other minor pneumatizations and standardize the mean incidence, distribution by sex, age and origin of these structures. Furthermore, it was aimed to examine the height, length, and width values of sinus septi nasi and crista galli pneumatizations, determine the measurement intervals and measurement values, and standardize them. The studies involving these pneumatizations were reviewed from various databases. After being evaluated according to the inclusion and exclusion criteria, 35 articles between the years 1991-2021 were reviewed. Based on the data obtained from these articles, we examined the incidence of sinus septi nasi, crista galli, and other minor pneumatizations. Middle nasal turbinate pneumatization had the highest incidence among all these pneumatizations. Uncinate process pneumatization had the lowest incidence. Considering the distribution by sex, no difference was found. Upon examining the age range, there were people aged between 1-95 years, and the mean age range was 33.05-41.48. The length, width and height values of crista galli and sinus septi nasi could not be standardized due to the insufficient number of studies and variable data in the literature. We believe that our study will contribute to similar future studies in larger populations with the clinical procedures to be performed in and around the nasal cavity.

Las variaciones en los senos paranasales y las neumatizaciones que se originan en estas estructuras son clínicamente importantes para los procedimientos quirúrgicos que se realizan en las regiones de la nariz y la cavidad nasal. En la revisión de la literatura no se encontró ninguna revisión sistemática que examinara el seno septi nasi, la crista galli y otras neumatizaciones menores. Este estudio tuvo como objetivo revisar los trabajos en la literatura que incluyen el seno septi nasi, la crista galli y otras neumatizaciones menores y estandarizar la incidencia media, la distribución por sexo, edad y origen de estas estructuras. Además, tuvo como objetivo examinar los valores de altura, longitud y ancho de las neumatizaciones del seno septi nasi y crista galli, determinar los intervalos de medición y los valores de medición, y estandarizarlos. Los estudios relacionados con estas neumatizaciones se revisaron a partir de varias bases de datos. Luego de ser evaluados según los criterios de inclusión y exclusión, se revisaron 35 artículos entre los años 1991-2021. Sobre la base de los datos obtenidos de estos artículos, examinamos la incidencia de septi nasi nasi, crista galli y otras neumatizaciones menores. La neumatización de la concha nasal media tuvo la mayor incidencia entre todas estas neumatizaciones. La neumatización del proceso uncinado tuvo la menor incidencia. Considerando la distribución por sexo, no se encontró diferencia. Al examinar el rango de edad, había personas con edades entre 1 y 95 años, y el rango de edad promedio fue de 33,05 a 41,48. Los valores de longitud, ancho y altura de crista galli y seno septi nasi no pudieron estandarizarse debido a la cantidad insuficiente de estudios y datos variables en la literatura. Creemos que nuestro estudio contribuirá a futuras investigaciones similares en poblaciones más grandes con los procedimientos clínicos que se realizarán en y alrededor de la cavidad nasal.

When morphology does not fit the genomes: the case of rodent olfaction.

Linking genes to phenotypes has been a major question in evolutionary biology for the last decades. In the genomic era, few studies attempted to link olfactory-related genes to different anatomical proxies. However, they found very inconsistent results. This study is the first to investigate a potential relation between olfactory turbinals and olfactory receptor (OR) genes. We demonstrated that despite the use of similar methodology in the acquisition of data, OR genes do not correlate with the relative and the absolute surface area of olfactory turbinals. These results challenged the interpretations of several studies based on different proxies related to olfaction and their potential relation to olfactory capabilities.

Numerical analysis of the ostiomeatal complex aeration using the CFD method.

We aimed to analyse ostiomeatal complex (OMC) aeration using the computational fluid dynamics (CFD) method of simulation based on human craniofacial computed tomography (CT) scans. The analysis was based on CT images of 2 patients: one with normal nose anatomy and one with nasal septal deviation (NSD). The Reynolds-Average Simulation approach and turbulence model based on linear eddy viscosity supplemented with the two-equation k-[Formula: see text] SST model were used for the CFD simulation. As a result, we found differences in airflow velocity through the ostiomeatal complex in patients with a normal nose and those with NSD. In a patient with NSD, the flow is turbulent in contrast to the normal nose (laminar flow). A faster (more intensive) airflow through the OMC was observed in the wider nasal cavity of the patient with NSD than on the narrower side. In addition, we want to emphasise the higher speed of airflow through the apex uncinate process area towards the ostiomeatal complex during exhalation, which, in the presence of secretions in the nose, predisposes to its easier penetration into the sinuses of the anterior group.

Morphology of pig nasal structure and modulation of airflow and basic thermal conditioning.

Mammals have presumably evolved to adapt to a diverse range of ambient environmental conditions through the optimized heat and mass exchange. One of the crucial biological structures for survivability is the nose, which efficiently transports and thermally preconditions the external air before reaching the internal body. Nasal mucosa and cavity help warm and humidify the inhaled air quickly. Despite its crucial role, the morphological features of mammal noses and their effect in modulating the momentum of the inhaled air, heat transfer dynamics, and particulate trapping remain poorly understood. Tortuosity of the nasal cavity in high-olfactory mammalian species, such as pigs and opossum, facilitates the formation of complex airflow patterns inside the nasal cavity, which leads to the screening of particulates from the inhaled air. We explored basic nasal features in anatomically realistic nasal pathways, including tortuosity, radius of curvature, and gap thickness; they show strong power-law correlations with body weight. Complementary inspection of tortuosity with idealized conduits reveals that this quantity is central in particle capture efficiency. Mechanistic insights into such nuances can serve as a tipping point to transforming nature-based designs into practical applications. In-depth characterization of the fluid-particle interactions in nasal cavities is necessary to uncover nose mechanistic functionalities. It is instrumental in developing new devices and filters in a number of engineering processes.

Strategies of vascularization of the ethmoid labyrinth in selected even-toed ungulates (Artiodactyla) and carnivores (Carnivora).

The anatomy of the nasal cavity and its structures, as well as other elements building a scaffold for olfactory organs, differs significantly among various groups of mammals. Understanding anatomical conditions of quality of olfaction are being studied worldwide and is a complex problem. Among many studies regarding bone and epithelial structures of turbinates and connected anatomical structures, few studies describe the vascularization of turbinates. Ethmoid turbinates are above all covered in olfactory epithelium containing branched axons that receive olfactory stimuli and as olfactory nerves penetrate the cribriform lamina of the ethmoid bone conveying information from smell receptors to the brain. Differences in vascularization of the cribriform plate and turbinates may add crucial information complementing studies regarding the olfactory organ's bone and soft tissue structures. In the study, we describe the vascularization of the cribriform plate of the ethmoid bone of 54 Artiodactyla and Carnivora.

Characterization of Airflow Parameters in the Olfactory Fissure Zone Based on Fluid Mechanics Method.

OBJECTIVE: Airflow in the olfactory fissure region is a necessary condition for olfaction. However, due to the complex anatomy of the olfactory fissure, it is difficult to characterize the airflow in this region. At present, there are few studies on the airflow characteristics of the olfactory fissure. The aim of this study is to investigate the characteristics of objective indicators of airflow parameters in the olfactory fissure region, such as flow velocity, flow rate, pressure and flow ratio, from the perspective of biofluid mechanics. METHODS: In this study, the anatomical structure of the olfactory fissure zone was reconstructed in three dimensions using raw data from 32 healthy adults and 64 sinus computed tomography scans. To study the characteristics of airflow parameter variations in the olfactory fissure region in healthy adults, 10 cross-sectional sections were established in the olfactory fissure region using computational fluid dynamics after obtaining the airflow parameter values at different anatomical positions in the olfactory fissure region. RESULTS: The average flow rate of the ten cross-sections in the olfactory fissure zone was 19.22±9.74 mL/s, the average flow velocity was 0.51±0.21 m/s, the average flow percentage was 5.45%±2.52%, and the average pressure was -13.35±6.74 Pa. The percentile method was used to determine the range of reference values for P90: average flow rate of 0.02-35.87 mL/s, average flow velocity of 0.24-0.94 m/s, average flow percentage of 1.57%-9.93%, and average pressure of -30.4-4.42 Pa. Among the ten cross-sectional systems of the olfactory fissure, the median of Plane3N-Plane8N is more stable and representative. In the olfactory fissure system, the corresponding anatomical position of Plane3N-Plane8N was in the posterior region of the olfactory fissure, mainly at the junction of the anterior, middle 1/3 to the posterior middle turbinate, which was consistent with the main distribution area of the olfactory mucosa. CONCLUSION: This study shows that the application of computational fluid dynamic can rapidly achieve the characterization of airflow parameters in the olfactory fissure. The airflow through the olfactory fissure in healthy adults accounted for no more than 10% of the total flow volume of the nasal cavity. The airflow parameters in the anterior region of the olfactory fissure fluctuated significantly, while those flowing through the posterior region of the olfactory fissure were more stable. This could be due to the anterior section of the middle turbinate truncating the restriction of airflow into the olfactory fissure.

Sinonasal Anatomy.

It is imperative for all imaging specialists to be familiar with detailed multiplanar computed tomography imaging anatomy of the paranasal sinuses and adjacent structures. This article reviews, in brief, the radiologically relevant embryology of the sinonasal region and discusses the imaging anatomy of the nasal cavity and paranasal sinuses. Radiologists should understand the importance and clinical implications of identifying the numerous anatomic variations encountered in this region and prepare a structured report that provides a surgical road map to the referring clinician.

Is nasal airflow disrupted after endoscopic skull base surgery? A short review.

Even the most delicate endonasal surgery for skull base lesion causes changes in the nasal cavity, some of them permanent. Morphological changes in the nasal cavity and their consequences (changes in nasal airflow) are often studied by advanced numerical analysis called computational fluid dynamics. This review summarizes current knowledge of endoscopic transsphenoidal skull base surgery effects on nasal airflow. Several studies have shown that endoscopic skull base surgery changes nasal anatomy to the extent that nasal airflow changes significantly postoperatively. Removing any intranasal structure increases the cross-sectional area of the respective nasal meatus, leading to increased nasal airflow in this area while airflow in the narrower periphery decreases. Middle turbinate resection increases airflow in the middle meatus and reduces airflow in the superior and inferior meatus. Small posterior septectomy does not cause a significant change in nasal airflow. Nasal septum deviation is an important factor in airflow changes. Current studies describe nasal changes after rather extensive procedures (e.g., middle turbinectomy, ethmoidectomy) that are unnecessary in routine pituitary adenoma surgery. No studies have compared changes using pre- and postoperative scans of the same patients after actual surgery.

Analyses on the influence of normal nasal morphological variations on odorant transport to the olfactory cleft.

OBJECTIVE: Olfaction requires a combination of sensorineural components and conductive components, but conductive mechanisms have not typically received much attention. This study investigates the role of normal nasal vestibule morphological variations in ten healthy subjects on odorant flux in the olfactory cleft. MATERIALS AND METHODS: Computed tomography images were used to create subject-specific nasal models. Each subject's unilateral nasal cavity was classified according to its nasal vestibule shape as Standard or Notched. Inspiratory airflow simulations were performed at 15 L/min, simulating resting inspiration using computational fluid dynamics modeling. Odorant transport simulations for three odorants (limonene, 2,4-dinitrotoluene, and acetaldehyde) were then performed at concentrations of 200 ppm for limonene and acetaldehyde, and 0.2 ppm for dinitrotoluene. Olfactory cleft odorant flux was computed for each simulation. RESULTS AND DISCUSSION AND CONCLUSION: Simulated results showed airflow in the olfactory cleft was greater in the Standard phenotype compared to the Notched phenotype. For Standard, median airflow was greatest in the anterior region (0.5006 L/min) and lowest in the posterior region (0.1009 L/min). Median airflow in Notched was greatest in the medial region (0.3267 L/min) and lowest in the posterior region (0.0756 L/min). Median olfactory odorant flux for acetaldehyde and limonene was greater in Standard (Acetaldehyde: Standard = 140.45 pg/cm2-s; Notched = 122.20 pg/cm2-s. Limonene: Standard = 0.67 pg/cm2-s; Notched = 0.65 pg/cm2-s). Median dinitrotoluene flux was greater in Notched (Standard = 2.86 × 10-4pg/cm2-s; Notched = 4.29 × 10-4 pg/cm2-s). The impact of nasal vestibule morphological variations on odorant flux at the olfactory cleft may have implications on individual differences in olfaction, which should be investigated further.

Anatomical, histochemical and surface ultrastructural characteristics of cavum nasi of the common quails (Coturnix coturnix. Erlangeri).

Ten normal, mature and common quails were used to study in detail the gross anatomy, histochemical and surface ultrastructural characteristics of the nasal cavity. The relationship between the structure and function of the nasal cavity also were assessed. The quail nasal cavity was divided into the vestibule, nasal cavity proper and fundus. The nasal cavity began rostrally by two slit-like external nares located laterally in the middle third of the upper beak. A previous authors stated that no rostral concha but the current study record that the rostral nasal concha was located opposite the nostrils and exhibited a C-shaped appearance in transverse section and was 5 mm long and 3 mm wide. The middle nasal concha was narrow and elongated. The caudal nasal concha was spherical, located caudodorsal to the rostral nasal concha and measured 2 mm in diameter. The infraorbital sinus was a roughly triangular cavity situated immediately rostral to the orbit. The histological and surface ultrastructural study of the nasal cavity of common quail did not studied previously. Histologically, the cavum nasi was composed of three regions: vestibule, respiratory and olfactory. The vestibule was lined with stratified squamous epithelium that was keratinized rostrally and non-keratinized caudally. The respiratory region was covered by pseudostratified columnar epithelium. Intra-epithelial mucous glands were present in the respiratory region and displayed a strong reaction with Alcian blue. The lining epithelium in the olfactory region was pseudostratified and contained olfactory, supporting and basal cells.

CT anatomy of the head in the Ile de France sheep.

BACKGROUND: CT scan images provide accurate anatomical data from different areas of the body that can be used to diagnose diseases. OBJECTIVES: The present work aimed to describe the normal anatomical structures of the Ile de France sheep head and its morphometric and volumetric properties using computed tomography (CT) and stereological methods. METHODS: Five adult Ile de France sheep heads, which were of mature age (above 10 months), were included in this study. The different cavities of the head, including the nasal cavity, paranasal sinuses, oral cavity, orbital cavity and vestibulocochlear system, were evaluated using CT scans, cross, sagittal and coronal sections. RESULTS: The mean length, height and width of the skull were 25.3 ± 1.02, 9.8 ± 0.93 and 12.3 ± 0.91 cm, respectively. The results showed that the nasal cavity is divided into three regions. Vestibular, respiratory and olfactory regions. The paranasal sinuses are composed of maxillary, frontal, palatine, sphenoid, lacrimal and ethmoidal that were identified and named in the CT scan images and their corresponding anatomical cross-sections. The total volume of the head, nasal cavity and oral cavity was estimated to be 2998 ± 202.00, 303 ± 31.33 and 229.3 ± 10.61 cm3 , respectively. CONCLUSIONS: The frontal sinus in the Ile de France sheep was limited to the frontal bone without extending into the parietal, temporal, or occipital bones, similar to Saanen goat. This study provided a comprehensive atlas of Ile de France sheep anatomy to internal medicine veterinarians and surgeons.

Complications of Nasopharyngeal Swabs and Safe Procedures for COVID-19 Testing Based on Anatomical Knowledge.

Nasopharyngeal swabs have been widely to prevent the spread of coronavirus disease 2019 (COVID-19). Nasopharyngeal COVID-19 testing is a generally safe and well-tolerated procedure, but numerous complications have been reported in the media. Therefore, the present study aimed to review and document adverse events and suggest procedural references to minimize preventable but often underestimated risks. A total of 27 articles were selected for the review of 842 related documents in PubMed, Embase, and KoreaMed. The complications related to nasopharyngeal COVID-19 testing were reported to be rarely happened, ranging from 0.0012 to 0.026%. Frequently documented adverse events were retained swabs, epistaxis, and cerebrospinal fluid leakage, often associated with high-risk factors, including severe septal deviations, pre-existing skull base defects, and previous sinus or transsphenoidal pituitary surgery. Appropriate techniques based on sufficient anatomical knowledge are mandatory for clinicians to perform nasopharyngeal COVID-19 testing. The nasal floor can be predicted by the line between the nostril and external ear canal. For safe testing, the angle of swab insertion in the nasal passage should remain within 30° of the nasal floor. The swab was gently inserted along the nasal septum just above the nasal floor to the nasopharynx and remained on the nasopharynx for several seconds before removal. Forceful insertion should be attempted, and alternative examinations should be considered, especially in vulnerable patients. In conclusion, patients and clinicians should be aware of rare but possible complications and associated high-risk factors. The suggested procedural pearls enable more comfortable and safe nasopharyngeal COVID-19 testing for both clinicians and patients.

Nasosinusal Endoscopic Anatomy and Physiology

The present article focuses on the analysis of the nasal cavity's anatomy succinctly and descriptively. This essay was carried out through a bibliographic review, directed to the detailed anatomy of the nasal cavity, and the structures that form its sinuses. We have identified the need formore studies directed to the related anatomical area so that the improved knowledge of this region ensures a nasoendoscopic treatment with better effectiveness and no complications.

Endoscopic Anatomy of the Lacrimal Sac: A Cadaveric Study.

OBJECTIVE: To describe the anatomy of the lacrimal sac in relation to the lateral nasal wall by cadaver dissection, and to measure the distances of surgically important landmarks from relevant structures for safer and more efficient surgery. METHOD: A total of 12 endoscopic dacryocystorhinostomy (DCR) were performed on both sides (right and left) of 6 fresh-frozen cadavers. The distances of the lacrimal sac to the posterior edge of the uncinate process, the frontal process of the maxilla, the maxillary ostium, the nasal vestibule, the middle turbinate attachment and the inferior turbinate were measured. In addition, the width and length of the lacrimal sac were measured. RESULTS: The mean width and length of the lacrimal sac were 5.6 mm and 11.1 mm, respectively. The lacrimal sac was located at 15.2 mm from the posterior edge of the uncinate process, at 35.5 mm from the nasal vestibule, at 13.5 mm from the maxillary ostium, at 12.2 mm from the frontal process of the maxilla, at 8.7 mm from the middle turbinate attachment, and at 7.3 mm from the inferior turbinate. CONCLUSION: This study provides additional measurements regarding the lacrimal sac and its relationships with nearby landmarks for use in endoscopic dacryocystorhinostomy. The distances of the lacrimal sac to the nasal vestibule, the uncinate process and the frontal process of the maxilla are not as reliable as the middle turbinate attachment for predicting the anatomic localization of the lacrimal sac during DCR.

The role of normal nasal morphological variations from race and gender differences on respiratory physiology.

This study identifies anatomical and airflow-induced relationships based on nasal morphological variations due to inter- and intra-racial differences and gender. Subject-specific nasal airway reconstruction was created from computed tomography images in 16 subjects: 4 subjects from each ethnic group (Black, East Asian, Caucasian, and Latino) comprising of 2 males and 2 females. Volume, surface area and nasal index were calculated, as well as airflow rate and nasal resistance after computational fluid dynamics simulations in the nasal airway. Results showed that nasal airspace surface area (p = 0.0499) and volume (p = 0.0281) were significantly greater in males than in females. Nasal volume was greatest in East Asians (Median = 20.38cm3, Interquartile Range [IQR] = 4.58 cm3), Latinos had the greatest surface area (Median = 219.70cm2, IQR = 29.56cm2). On average, East Asian and Black females had larger nasal index than their male counterparts. Caucasians had the highest median nasal resistance (0.050 Pa.s/mL, IQR = 0.025 Pa.s/mL). Results indicate that there exist anatomical variabilities based on race and gender. However, these variabilities may not significantly influence nasal function.