Characterizing regional drug delivery within the nasal airways

INTRODUCTION

The nose has been receiving increased attention as a route for drug delivery. As the site of deposition constitutes the first point of contact of the body with the drug, characterization of the regional deposition of intranasally delivered droplets or particles is paramount to formulation and device design of new products.

AREAS COVERED

This review article summarizes the recent literature on intranasal regional drug deposition evaluated in vivo, in vitro and in silico, with the aim of correlating parameters measured in vitro with formulation and device performance. We also highlight the relevance of regional deposition to two emerging applications: nose-to-brain drug delivery and intranasal vaccines.

EXPERT OPINION

As in vivo studies of deposition can be costly and time-consuming, researchers have often turned to predictive in vitro and in silico models. Variability in deposition is high due in part to individual differences in nasal geometry, and a complete predictive model of deposition based on spray characteristics remains elusive. Carefully selected or idealized geometries capturing population average deposition can be useful surrogates to in vivo measurements. Continued development of in vitro and in silico models may pave the way for development of less variable and more effective intranasal drug products.

Quantification of Heavy Metals in the Nasal Turbines of Smokers and Nonsmokers

OBJECTIVES

Cigarette smoke is known to contain toxic heavy metals. In this study, heavy metal levels in the nasal turbinate tissues of smokers and nonsmokers were measured and compared with Inductively Coupled Plasma-Mass Spectrometry (ICP-MS).

METHODS

Forty patients who come to the Otorhinolaryngology outpatient clinic due to nasal obstruction and are given an appointment for partial turbinate reduction operation due to inferior turbinate hypertrophy, according to their smoking status, were divided into two groups: those who had smoked one pack/day for at least 10 years and those who had never smoked. The levels of heavy metals (Al, As, Ba, Cd, Cr, Co, Cu, Pb, Mn, Hg, Ni, Se, and Ag) were compared by ICP-MS in nasal turbinate tissues.

RESULTS

Al (p = 0.002), Cr (p < 0.001), Co (p < 0.001), Ni (p = 0.001), Cu (p < 0.001), As (p < 0.001), Se (p < 0.001), Ag (p < 0.001), Cd (p = 0.001), Ba (p = 0.008), Hg (p < 0.001), and Pb (p < 0.001) values in the smoker group were found to be significantly higher than the values of nonsmokers. Although the Mn level was high in smokers, no significant difference was observed (p = 0.299).

CONCLUSIONS

Smoking can cause nasal and sinus problems. In this study, we observed that the smoking group had significantly higher levels of almost all the heavy metals investigated in the nasal turbinate tissues. As smoking damages, the mucociliary system and the mucosa, heavy metals from cigarettes may accumulate further and cause harm to the nasal tissues.

LEVEL OF EVIDENCE

Level 3 Laryngoscope, 2024.

Rhinitis medicamentosa - comparing two treatment strategies: a retrospective analysis

OBJECTIVE

Rhinitis medicamentosa poses a therapeutic challenge for both patients and physicians. Treatment strategies vary, starting with avoidance of decongestants, followed by medications or surgical intervention. This study aimed to compare two treatment strategies for this condition.

METHODS

A review was conducted of patients diagnosed with rhinitis medicamentosa from 2013 to 2021, who were managed conservatively with medications or surgically by inferior turbinate reduction.

RESULTS

Forty-seven patients were included: 21 patients were treated conservatively and 26 underwent turbinate reduction. Following surgical therapy, the frequency of using decongestants was significantly reduced (p < 0.001), with a significant improvement in Sino-Nasal Outcome Test-22 scores (p < 0.001). The conservative treatment group was significantly older with more co-morbidities. Following medical therapy, the conservative treatment group had a significant decrease in the frequency of decongestant use, but there was no significant improvement in their Sino-Nasal Outcome Test-22 scores.

CONCLUSION

Compared to conservative treatment, inferior turbinate reduction for rhinitis medicamentosa resulted in reduced decongestant use and improved quality of life.

Evaluation of Anatomical Variations of the Maxillary Sinus in Patients With and Without Mucous Retention Cyst

Objectives: Mucous retention cyst (MRC) is a benign and self-limited lesion that can be caused by many risk factors, including anatomical variations of the sinonasal region. This study aims to investigate the relationship between anatomical variations and the presence of MRC. Materials and Methods: In total, 2109 sinonasal cone beam computed tomography images were evaluated for the presence of MRC, and the sinonasal anatomical regions such as the osteomeatal complex (OMC), infundibulum length, ostium height, the diameter of the ostium, the presence of accessory ostium, concha bullosa, and mucosal thickening of the maxillary sinuses. Shapiro-Wilk normality test, independent sample t-test, and chi-square test were used for statistical analysis, and P < .05 was considered significant. Results: The prevalence of MRC was 119 (5.6%) cases. The average diameter of the ostium in cases with and without MRC was 0.49 ± 0.41 mm and 0.99 ± 0.76 mm, respectively, which showed a significant inverse relationship(P < .001). A significant relationship was found between the septum deviation, the ostium height, the concha bullosa, and the accessory ostium with the presence of MRC (P < .001). Conclusions: Sinonasal anatomical variations such as ostium diameter, ostium height, septal deviation, the presence of accessory ostium, and concha bullosa can cause MRC development, and considering that surgery may be necessary in some cases; this could be of great importance to clinicians and surgeons for treatment and prevention of development or recurrence of these pseudocysts in patients.

Characteristics of Human Nasal Turbinate Stem Cells under Hypoxic Conditions

This study investigated the influence of hypoxic culture conditions on human nasal inferior turbinate-derived stem cells (hNTSCs), a subtype of mesenchymal stem cells (MSCs). It aimed to discern how hypoxia affected hNTSC characteristics, proliferation, and differentiation potential compared to hNTSCs cultured under normal oxygen levels. After obtaining hNTSCs from five patients, the samples were divided into hypoxic and normoxic groups. The investigation utilized fluorescence-activated cell sorting (FACS) for surface marker analysis, cell counting kit-8 assays for proliferation assessment, and multiplex immunoassays for cytokine secretion study. Differentiation potential-osteogenic, chondrogenic, and adipogenic-was evaluated via histological examination and gene expression analysis. Results indicated that hNTSCs under hypoxic conditions preserved their characteristic MSC phenotype, as confirmed by FACS analysis demonstrating the absence of hematopoietic markers and presence of MSC markers. Proliferation of hNTSCs remained unaffected by hypoxia. Cytokine expression showed similarity between hypoxic and normoxic groups throughout cultivation. Nevertheless, hypoxic conditions reduced the osteogenic and promoted adipogenic differentiation potential, while chondrogenic differentiation was relatively unchanged. These insights contribute to understanding hNTSC behavior in hypoxic environments, advancing the development of protocols for stem cell therapies and tissue engineering.

Nasal turbinates of the dicynodont Kawingasaurus fossilis and the possible impact of the fossorial habitat on the evolution of endothermy

The nasal region of the fossorial anomodont Kawingasaurus fossilis was virtually reconstructed from neutron-computed tomographic data and compared with the terrestrial species Pristerodon mackayi and other nonmammalian synapsids. The tomography of the Kawingasaurus skull reveals a pattern of maxillo-, naso-, fronto- and ethmoturbinal ridges that strongly resemble the mammalian condition. On both sides of the nasal cavity, remains of scrolled maxilloturbinals were preserved that were still partially articulated with maxilloturbinal ridges. Furthermore, possible remains of the lamina semicircularis as well as fronto- or ethmoturbinals were found. In Kawingasaurus, the maxilloturbinal ridges were longer and stronger than in Pristerodon. Except for the nasoturbinal ridges, no other ridges in the olfactory region and no remains of turbinates were recognized. This supports the hypothesis that naso-, fronto-, ethmo- and maxilloturbinals were a plesiomorphic feature of synapsids, but due to their cartilaginous nature in most taxa were, in almost all cases, not preserved. The well-developed maxilloturbinals in Kawingasaurus were probably an adaptation to hypoxia-induced hyperventilation in the fossorial habitat, maintaining the high oxygen demands of Kawingasaurus' large brain. The surface area of the respiratory turbinates in Kawingasaurus falls into the mammalian range, which suggests that they functioned as a countercurrent exchange system for thermoregulation and conditioning of the respiratory airflow. Our results suggest that the environmental conditions of the fossorial habitat led to specific sensory adaptations, accompanied by a pulse in brain evolution and of endothermy in cistecephalids, ~50 million years before the origin of endothermy in the mammalian stem line. This supports the Nocturnal Bottleneck Theory, in that we found evidence for a similar evolutionary scenario in cistecephalids as proposed for early mammals.

Effectiveness of the Treatment of Rhinogenic Headache Caused by Intranasal Contact

OBJECTIVES

The aim of the study is to evaluate the effectiveness of the surgical and nonsurgical treatment of headache caused by contact points (CPs) between the nasal septum and inferior or middle turbinate.

METHODS

The research was designed as a prospective clinical case-series study. The patients with CP headaches were offered to choose between 2 treatment options, surgery and medical treatment. Two groups of surgically treated patients (surgery groups 1 and 2, depending on whether there is a contact between nasal septum and inferior turbinate or middle turbinate) were evaluated and compared for headache intensity and frequency. Headache intensity was measured using a visual analog scale value from 0 to 10; the frequency of headache was expressed as the number of days during 1 month with a headache (before surgery, 1 month, and 6 months after surgery). A comparison was also made between surgically and nonsurgically treated patients.

RESULTS

We found more intensive and frequent headache in patients who had CP between the nasal septum and the middle turbinate (P = .038 and P = .003, respectively). A significant reduction in headache intensity and frequency was found in both groups of surgically treated patients 6 months after surgery; however, this reduction was more significant in patients with mucosal contact between nasal septum and middle turbinate. The nonsurgical treatment made a significant reduction of headache intensity and frequency at 1-month follow-up (P = .012 and P = .031, respectively), but not at 6-month follow-up (P = .114 and P = .088, respectively).

CONCLUSION

Surgery gave a statistically significant reduction in the intensity and frequency of headache, which was assessed 6 months after surgery. Surgery was found as superior to nonsurgical treatment in the therapy of CP headache.

A Comparison of Symptom Improvement and Outcomes After Septoplasty Alone Versus Septoplasty With Turbinoplasty

Background Various causes can lead to nasal obstruction, with the most frequent anatomical cause being deviated nasal septum. It seriously affects patients' quality of life. As a result, septoplasty is performed to enhance the nasal airways. This study aimed to compare the improvement of nasal symptoms following septoplasty with or without turbinoplasty and evaluate the surgical outcomes in both different groups. Methodology A retrospective study was conducted at a tertiary hospital among patients who had undergone septoplasty with or without turbinoplasty between 2020 and 2022. Data regarding demographics, clinical features, surgical data, and complications were collected from patient files. The Nasal Obstruction Symptom Evaluation (NOSE) scale score was assessed through structured interviews. Results In our analysis of 209 patients who underwent surgery for deviated nasal septum, septoplasty was done in 110 (52.6%) patients, whereas the remaining 99 (47.4%) underwent septoplasty with turbinoplasty. The mean NOSE score was found to be 32.94 ± 35.67%. Patients who underwent septoplasty alone significantly showed higher mean scores (56.36 ± 34.62%) compared to those who underwent septoplasty with turbinoplasty (11.14 ± 18.93%) (p < 0.001). The long-term complications showed revision surgery was done in 13 patients, which was comparatively more often done in patients who underwent a septoplasty. Other long-term complications were found to be significantly higher in patients who underwent septoplasty (76.9%) compared to those who underwent septoplasty with turbinoplasty (23.1%). Conclusions Patients who underwent additional turbinoplasty experienced an improvement in nasal symptoms than those who underwent septoplasty alone. In addition, more long-term complications were noted in patients who underwent septoplasty alone.

Ontogenetic transformation of the cartilaginous nasal capsule in mammals, a review with new observations on bats

The nasal capsule, as the most rostral part of the chondrocranium, is a critical point of connection with the facial skeleton. Its fate may influence facial form, and the varied fates of cartilage may be a vehicle contributing to morphological diversity. Here, we review ontogenetic changes in the cartilaginous nasal capsule of mammals, and make new observations on perinatal specimens of two chiropteran species of different suborders. Our observations reveal some commonalities between Rousettus leschenaultii and Desmodus rotundus, such as perinatal ossification of the first ethmoturbinal. However, in Rousettus, ossification of turbinals is demonstrated as either perichondrial or endochondral. In Desmodus, perichondrial and endochondral ossification of the posterior nasal cupula is observed at birth, a part of the nasal capsule previously shown to persist as cartilage into infancy in Rousettus. Combined with prior findings on cranial cartilages we identify several diverse transformational mechanisms by which cartilage as a tissue type may contribute to morphological diversity of the cranium. First, cartilage differentiates in an iterative fashion to increase nasal complexity, but still retains the capacity for later elaboration via de novo bone emanating outward before or after cartilage ossifies. Second, cartilage acts as a driver of growth at growth centers, or via interstitial growth (e.g., septal cartilage). Finally, cartilage as a tissue may influence the timing of ossification and union of the facial and basicranial skeleton. In particular, cartilage at certain points of ontogeny may "model" via selective resorption, showing some similarity to bone.

Optimizing Quality of Life and Minimizing Morbidity through Nasal Preservation in Endoscopic Skull Base Surgery: A Contemporary Review

Introduction  Endoscopic endonasal approaches (EEAs) are increasingly utilized for intracranial pathology. As opposed to sinonasal tumors, the nasal cavity is being used as a corridor to access these intracranial tumors but is not the site of primary surgical intent. Accordingly, there has been recent interest in preserving intranasal structures not directly involved by tumor and improving postoperative sinonasal quality of life (QOL). Objectives  The aim of the study is to highlight recent advances in EEA techniques focused on improving sinonasal QOL including turbinate preservation, reducing the morbidity of reconstructive techniques, and the development of alternative minimally invasive EEA corridors. Methods  The method of the study involves contemporary literature review and summary of implications for clinical practice. Results  Nasoseptal flap (NSF) harvest is associated with significant morbidity including septal perforation, prolonged nasal crusting, and external nasal deformities. Various grafting and local rotational flaps have demonstrated the ability to significantly limit donor site morbidity. Free mucosal grafts have re-emerged as a reliable reconstructive option for sellar defects with an excellent sinonasal morbidity profile. Middle turbinate preservation is achievable in most EEA cases and has not been shown to cause postoperative obstructive sinusitis. Recently developed minimally invasive EEA techniques such as the superior ethmoidal approach have been described to better preserve intranasal structures while allowing intracranial access to resect skull base tumors and have shown promising sinonasal QOL results. Conclusion  This contemporary review discusses balancing effective skull base reconstructive techniques with associated morbidity, the role of turbinate preservation in EEA, and the development of unique EEA techniques that allow for increased nasal structure preservation.

Pyriform Turbinoplasty and Lateral Nasal Wall Lateralization: Practical Hints on How We Do It

Pyriform turbinoplasty (PT) is a surgical option for the management of turbinate hypertrophy. The philosophy and goal of the procedure are to improve the symptoms of a restricted airway while preserving function. We report a case of surgical management of inferior turbinate (IT) hypertrophy with PT and lateral nasal wall lateralization (LNWL). PT and LNWL improve nasal airflow, providing a wider nasal cavity by the removal of the bone of the IT. Sustained symptomatic improvement has been documented and is less susceptible to the influence of turbinate hypertrophy with other techniques.

Ambiguous "olfactory" terms for anatomic spaces adjacent to the cribriform plate: A publication database analysis and quest for uniformity

A precise nomenclature and terminology is the foundation of communication in Anatomy and related biomedical sciences. The olfactory bulbs and nerves lie above and below the cribriform plate (CP), respectively. Hence, many anatomical landmarks in this region have names adopting the term "olfactory" as qualifiers. Ambiguous use of these "olfactory" terms exists, with some potential repercussions on patient treatments. We performed a publication database analysis to determine the frequency of misuse of names for seven anatomical "olfactory" spaces close to the CP and nasal cavity. We searched PubMed® publications having the keyword "olfactory" in their title or abstract, plus one of seven other keywords: "groove", "fossa", "recess", "cleft", "vestibule", "sulcus", and "cistern". We reviewed all abstracts for accuracy of these terms relative to accepted norms or customary definitions. By February 2020, we found all these keywords in 1255 articles. For the terms olfactory "groove" and "fossa", the number of relevant articles (and percentage of those inaccurately using these terms) were 374 (1.1%), and 49 (8.2%), respectively. All 52 abstracts containing "olfactory" and "vestibule" were irrelevant, relating to the "nasal vestibule" and olfactory function, instead of "olfactory vestibule". Overall, terms used to describe "olfactory" spaces near the CP are seldom ambiguous or inaccurate, but the terms olfactory "groove" and "fossa" are occasionally misused, We propose several new "olfactory" terms for inclusion in the Terminologia Anatomica, and stress the need for uniform nomenclature leading to greater consistency and accuracy in clinical use of anatomical terms containing the word "olfactory" as a descriptor.

Concha Bullosa of the Inferior Turbinate

Inferior concha bullosa is a rare disease that has been related to sinonasal symptoms. This study aimed to determine the characteristics of concha bullosa in the inferior turbinate and assess its common clinical manifestations, computed tomography findings, and the surgical techniques used to treat the condition. We conducted a search of the PubMed database, using the Preferred Reporting Items of Systematic Reviews and Meta-Analysis, for articles published until May 2021 using the following terms: "inferior turbinate and concha bullosa"; "inferior turbinate and pneumatization"; and in combination with other terms such as "concha bullosa release and concha bullosa excision", among others. We found 12 papers that met our inclusion criteria. The main presenting symptom was a nasal obstruction in 13 patients (100%), followed by headache in 10 patients (77%). The site of inferior concha bullosa was bilateral in six cases and left-sided in five cases. Computed tomography was conducted in all cases in this review. The type of intervention performed was medical, surgical, and both in 23%, 54%, and 23% of the cases. Despite multimodal surgical approaches and medical treatment, all the outcomes were good and no compactions were noted. All cases also had good prognoses.

How I Do It: Inferior Turbinectomy: Modified Techniques for Submucosal Resection

Although inferior turbinectomy with submucosal resection effectively reduces the volume of the inferior turbinate, there is room for improvement in surgical procedures. Techniques have been developed to reduce crusting and bleeding while efficiently achieving volume reduction. State-of-the-art procedures pertaining to the local injection site, incision line, exposure of the periosteum, submucosal outfracture of the turbinate bone, trimming of redundant mucosa, and incision line suturing are described. Pre and postoperative Nasal Obstruction Symptom Evaluation (NOSE) scores and postoperative inferior turbinate bleeding and crusting were evaluated. For the 18 consecutive patients analyzed, the pre and postoperative NOSE scores were 67.8 ± 14.8 and 16.1 ± 13.0, respectively (P = .0002). Postoperatively, bleeding was absent, and only minor suture thread crusting was observed in 13 patients. In conclusion, our novel technique improves the effectiveness of surgery as well as the postoperative quality of the inferior turbinate.

TUSC (TUrbinate Surgery Classification): A Novel Classification Proposal for Turbinate Surgery

Aim of this manuscript is to propose a clear and easily applicable classification for turbinate surgery, based on the use of a numerical model, which could be introduced in the practice of Otolaryngologists and Maxillo-Facial surgeons.Applying this classification, it will be possible to offer an easy format when describing which turbinates are involved in a procedure, and to offer a quick method to record and analyse clinical data, also for scientific purpose.

Feasibility of Implementing Opioid Stewardship Recommendations for Sinonasal Surgery

OBJECTIVE

The objective of our study was to review the current literature pertaining to perioperative opioids in sinus surgery and to determine the effects of implementing opioid stewardship recommendations in the setting of endoscopic sinonasal surgery.

STUDY DESIGN

Single-institution retrospective case-control study.

SETTING

Academic medical center outpatient area.

METHODS

This retrospective review comprised 163 patients who underwent routine functional endoscopic sinus surgery, septoplasty, and/or inferior turbinate reduction before and after implementation of a standardized pain control regimen based on published opioid stewardship recommendations. The regimen consisted of an oral dose of gabapentin (400 mg) and acetaminophen (1000 mg) at least 30 minutes prior to surgery, absorbable nasal packing soaked in 0.5% tetracaine intraoperatively, and a postoperative regimen of acetaminophen and nonsteroidal anti-inflammatory medications. Tramadol tablets (50 mg) were prescribed postoperatively for breakthrough pain. The primary outcome measure for the study was the average number of hydrocodone equivalents (5 mg) prescribed before and after the new protocol.

RESULTS

The average number of opioid medications prescribed, measured as hydrocodone equivalents (5 mg), decreased from 24.59 preprotocol to 18.08 after the initiation of the new perioperative regimen (P < .001). There was no significant difference between the periods (P > .05) in number of postoperative phone calls regarding pain or in patient satisfaction scores.

CONCLUSION

Opioid stewardship recommendations can be instituted for sinonasal surgery, including multimodal perioperative pain management and substitution of tramadol for breakthrough pain, as a method to decrease the volume of opioids prescribed, without increasing patient phone calls or affecting the likelihood of physician recommendation Press Ganey scores.

Fissures, folds, and scrolls: The ontogenetic basis for complexity of the nasal cavity in a fruit bat (Rousettus leschenaultii)

Mammalian nasal capsule development has been described in only a few cross-sectional age series, rendering it difficult to infer developmental mechanisms that influence adult morphology. Here we examined a sample of Leschenault's rousette fruit bats (Rousettus leschenaultii) ranging in age from embryonic to adult (n = 13). We examined serially sectioned coronal histological specimens and used micro-computed tomography scans to visualize morphology in two older specimens. We found that the development of the nasal capsule in Rousettus proceeds similarly to many previously described mammals, following a general theme in which the central (i.e., septal) region matures into capsular cartilage before peripheral regions, and rostral parts of the septum and paries nasi mature before caudal parts. The ossification of turbinals also generally follows a rostral to the caudal pattern. Our results suggest discrete mechanisms for increasing complexity of the nasal capsule, some of which are restricted to the late embryonic and early fetal timeframe, including fissuration and mesenchymal proliferation. During fetal and early postnatal ontogeny, appositional and interstitial chondral growth of cartilage modifies the capsular template. Postnatally, appositional bone growth and pneumatization render greater complexity to individual structures and spaces. Future studies that focus on the relative contribution of each mechanism during development may draw critical inferences how nasal morphology is reflective of, or deviates from the original fetal template. A comparison of other chiropterans to nasal development in Rousettus could reveal phylogenetic patterns (whether ancestral or derived) or the developmental basis for specializations relating to respiration, olfaction, or laryngeal echolocation.

Identification of Significant Anatomical Variations in the Nose and Anterior Skull Base Using Computed Tomography: A Cross-Sectional Study

Introduction This study is aimed at the identification of anatomic variations in the nose, paranasal sinuses (PNS), and anterior skull base, which are substantially important to ensure safe and complete endoscopic sinus and skull base surgery. Materials and methods This cross-sectional study was conducted at the Dow Institute of Radiology, Dow International Medical College, Dow University Hospital. We included adult patients (i.e., those aged 18 years or older) undergoing a non-contrast CT of the nose and PNS. Two consultant radiologists reviewed the scans on the picture archiving and communication system independently. Any conflict was resolved with consensus. Anatomical variations in the nose, PNS, and anterior skull base of both sides were evaluated. Results We reviewed the CT of the PNS of 130 patients with an age of 35.8 ± 14.48 years (mean ± standard deviation). The proportion of men (64/130; 49.2%) and women (66/130; 50.8%) was equal. All patients had one or more variations. The most common abnormality was a deviated nasal septum (DNS), observed in 115 of 130 participants (88.5%) with unilateral occurrence predominant. It was followed by inferior nasal turbinate hypertrophy and agger nasi cells in 76.2% and 67.7% patients, respectively. Optic nerve variation type I (160/260 sinuses; 61.5%) and Keros type II, for olfactory depth (162/260 sinuses; 62.3%), were most common. Conclusions Here we report anatomical variations in PNS in all patients of our study; the commonest of all anatomical variations was a DNS. A CT scan is instrumental in surgical planning and patient safety in functional endoscopic sinus surgery.

Isolated Topical Decongestion of the Nasal Septum and Swell Body Is Effective in Improving Nasal Airflow

Background

Topical nasal decongestant sprays are used commonly in routine otolaryngology practice to reduce the symptoms of nasal airway obstruction (NAO) through vasoconstriction, thereby reducing the bulk of vasoerectile tissue and increasing nasal airflow. Such tissue is found predominantly on the lateral wall of the nose within the inferior turbinates (ITs), but recent evidence suggests that it may also be found medially within the nasal septal swell body (SSB).

Objective

To determine whether isolated topical decongestion of the medial nasal wall, targeting the SSB, is as effective as isolated decongestion of the lateral nasal wall, targeting the IT, in maximizing nasal patency.

Methods

A double-blinded, randomized controlled, crossover study was performed investigating the effect of decongestion of the lateral nasal wall or septum in isolation on nasal airflow. Isolated decongestion was performed by placing a cottonoid, soaked in oxymetazoline and attached to a silastic sheet, into the nasal cavity randomly facing either the septum or lateral nasal wall, bilaterally. Anterior rhinomanometry, acoustic rhinometry, peak nasal inspiratory flow (PNIF), and subjective patient-reported outcomes (Sinonasal Outcome Test (SNOT-22) and Nasal Obstruction Symptom Evaluation (NOSE) scores) were recorded at baseline and postdecongestion. Decongestion of the alternate site was then performed at a later date.

Results

A total of 20 healthy volunteers (30% females, mean age 26.6 ± 3.8 years) were recruited. Improvements in nasal obstruction and SNOT-22 scores were found following decongestion of the septum compared with baseline (mean difference: 0.82, t = 2.32, P = .04; mean difference: 3.30, t = 2.50, P = .04, respectively). Improvements in mean inspiratory flow, minimal cross-sectional area, volume, and PNIF were also demonstrated.

Conclusion

This study suggests that the SSB contains erectile tissue that responds to topical decongestant therapy in a similar manner to IT tissue. The SSB may represent a novel target in surgery for NAO.

Partial Preservation of the Inferior Turbinate in Endoscopic Medial Maxillectomy: A Computational Fluid Dynamics Study

Background

Endoscopic medial maxillectomy (EMM) is a workhorse for multiple sinonasal conditions. To reduce its burden on the sinonasal physiology, several modified EMM (M-EMM) have been proposed. Objective: In order to provide a theoretical basis for EMM and its modifications, this study introduces a computational fluid dynamics (CFD) model, based on a time-resolved direct numerical simulation, describing EMM and assessing the role of the M-EMM in preserving the overall fluid dynamics of the sinonasal cavities.

Methods

A normal sinonasal CT scan was converted into a geometrical model and used as a reference; 2 anatomies were then created by virtual surgery, mimicking EMM and M-EMM, with the latter sparing the anterior portion of inferior turbinate and medial maxillary sinus wall. The airflow was simulated in the models via the OpenFOAM CFD software and compared in terms of flow rate, mean and fluctuating velocity, vorticity, and turbulent structures.

Results

The analysis shows that EMM induces a massive flow rate increase in the operated side, which becomes less obvious in the M-EMM model. In contrast to M-EMM, EMM induces higher velocity fields that reach the maxillary sinus. Velocity and vorticity fluctuations are negligible in the baseline model, but become increasingly evident and widespread in the M-EMM and EMM models.

Conclusions

A significant disruption of the nasal fluid dynamics is observed in EMM, while M-EMM minimizes variations and reduces interference with nasal air conditioning. Our analysis provides insights into the pathophysiology of radical sinus surgery and provides a theoretical basis for the ability of M-EMM to reduce the temporary surgery-related changes on both healthy and operated sides.

Reduction of olfactory and respiratory turbinates in the transition of whales from land to sea: the semiaquatic middle Eocene Aegyptocetus tarfa

Ethmoturbinates, nasoturbinates, and maxilloturbinates are well developed in the narial tract of land-dwelling artiodactyls ancestral to whales, but these are greatly reduced or lost entirely in modern whales. Aegyptocetus tarfa is a semiaquatic protocetid from the middle Eocene of Egypt. Computed axial tomography scans of the skull show that A. tarfa retained all three sets of turbinates like a land mammal. It is intermediate between terrestrial artiodactyls and aquatic whales in reduction of the turbinates. Ethmoturbinates in A. tarfa have 26% of the surface area expected for an artiodactyl. These have an olfactory function and indicate that early whales retained a sense of smell in the transition from land to sea. Maxilloturbinates in A. tarfa have 6% of the surface area expected for an artiodactyl. These have a respiratory function and their markedly reduced size suggests that rapid inhalation and exhalation was already more important than warming and humidifying air, in contrast to extant land mammals. Finally, the maxilloturbinates of A. tarfa, although greatly reduced, still show some degree of similarity to those of artiodactyls, supporting the phylogenetic affinity of cetaceans and artiodactyls based on morphological and molecular evidence.

Evolutionary adaptation to aquatic lifestyle in extinct sloths can lead to systemic alteration of bone structure

Through phenotypic plasticity, bones can change in structure and morphology, in response to physiological and biomechanical influences over the course of individual life. Changes in bones also occur in evolution as functional adaptations to the environment. In this study, we report on the evolution of bone mass increase (BMI) that occurred in the postcranium and skull of extinct aquatic sloths. Although non-pathological BMI in postcranial skeleton has been known in aquatic mammals, we here document general BMI in the skull for the first time. We present evidence of thickening of the nasal turbinates, nasal septum and cribriform plate, further thickening of the frontals, and infilling of sinus spaces by compact bone in the late and more aquatic species of the extinct sloth Thalassocnus Systemic bone mass increase occurred among the successively more aquatic species of Thalassocnus, as an evolutionary adaptation to the lineage's changing environment. The newly documented pachyostotic turbinates appear to have conferred little or no functional advantage and are here hypothesized as a correlation with or consequence of the systemic BMI among Thalassocnus species. This could, in turn, be consistent with a genetic accommodation of a physiological adjustment to a change of environment.

Influence of a medialized middle turbinate on olfactory function: a prospective randomized double-blind study

BACKGROUND

Medialization of the middle turbinate (MT) is an effective technique to prevent recurrent rhinosinusitis but could, in theory, reduce olfactory function by interfering the odorants to reach the olfactory mucosae. We performed a prospective randomized double-blind trial under the hypothesis that olfactory functions would be affected by the status of olfactory mucosae, not by MT medialization.

METHODS

In randomly selected sides, the unilateral MT was medialized in 80 patients undergoing bilateral endoscopic sinus surgery for chronic rhinosinusitis. The status of the bilateral olfactory cleft (OC) was photodocumented intraoperatively and categorized into patent (normal or mucosal swelling with discharge) and congested (hypertrophied mucosae or nasal polyps) groups. The butanol threshold test (BTT) was conducted in each nostril before and 6 months after the surgery. Correlation between the BTT scores and MT medialization or the OC status was assessed. No smell identification test was conducted side by side, which might limit clinical implications.

RESULTS

In total, 46 of 80 patients completed the trial. MT medialization was performed on the left and right side of the nose in 19 and 27 cases, respectively. The intraoperative OC status did not differ between the 2 sides. Perioperative changes in the BTT scores were similar between the medialized and intact MT sides, whereas the preoperative and postoperative BTT scores were higher in the patent OC group than in the congested OC group, regardless of side.

CONCLUSION

MT medialization does not impair olfactory function, and OC status is closely related to olfactory function.

Sculpting the skull through neurosensory epithelial-mesenchymal signaling

The vertebrate skull is a complex structure housing the brain and specialized sensory organs, including the eye, the inner ear, and the olfactory system. The close association between bones of the skull and the sensory organs they encase has posed interesting developmental questions about how the tissues scale with one another. Mechanisms that regulate morphogenesis of the skull are hypothesized to originate in part from the encased neurosensory organs. Conversely, the developing skull is hypothesized to regulate the growth of neurosensory organs, through mechanical forces or molecular signaling. Here, we review studies of epithelial-mesenchymal interactions during inner ear and olfactory system development that may coordinate the growth of the two sensory organs with their surrounding bone. We highlight recent progress in the field and provide evidence that mechanical forces arising from bone growth may affect olfactory epithelium development. Developmental Dynamics 248:88-97, 2019. © 2018 Wiley Periodicals, Inc.

Anatomical Variations of the Middle Turbinate Concha Bullosa and its Relationship with Chronic Sinusitis: A Prospective Radiologic Study

Introduction  A pneumatized turbinate, also called concha bullosa, is a normal anatomical variant of the paranasal sinus region. Depending on the site of pneumatization, the concha is classified into extensive, bulbous or lamellar type. The middle turbinate concha bullosa has been implicated as a possible etiological factor in chronic sinusitis. Objectives  The aim of this study was to investigate the anatomical variations of the concha bullosa, based on paranasal sinus imaging, and its possible association with sinusitis. Methods  This prospective descriptive study was performed at the Department of ENT and Head Neck Surgery over a period of one year, from 2016 to 2017. We studied the computed tomography scans of the nose and paranasal sinuses- in axial, coronal and sagittal planes-of patients who had symptoms of nasal obstruction, or headache and features of chronic sinusitis. Results  Out of the 202 scans studied, the prevalence of concha bullosa was 31.7%. The concha was bilateral in 35 (54.7%) patients and unilateral in 29 (45.3%) patients. Out of 99 conchae, 54 were on the right side and 45 were on left side. Ipsilateral sinusitis was found in 40.4% of the sides in the scans of subjects with concha. There was no statistically significant association between any type of middle turbinate concha with sinusitis, but sinusitis was more predominant with the extensive type of concha ( p  > 0.05). Conclusion  Multiple air cells, mucocele, pyocele and inflammatory mucosal thickenings in the concha are relatively rare. Detailed knowledge of anatomic variations of the concha bullosa is imperative for the radiologists and the operating surgeons.

Inferior Turbinate Swing Technique: A Novel Surgical Route to Approach Maxillary Sinus Area Pathology

The inferior turbinate is an important structure for maintenance of adequate physiologic function within the nasal cavity. However, it hampers access to lesions involving maxillary sinus areas, including postoperative mucocele or benign tumor, and acts as an inferior limit to widening the natural ostium of a maxillary sinus. Here, we introduce a novel technique, interior turbinate swing, to facilitate entry to the inferior meatus or maxillary sinus while maintaining integrity of the inferior turbinate. In this technique, the anterior part of inferior turbinate is cut with sharp scissors, rotated posteriorly, and held in the nasopharynx. The inferior turbinate swing technique was employed in 38 subjects, and no patients exhibited recurrence of the causative disease without complication. Therefore, we may conclude that the inferior turbinate swing technique is a simple, effective, and safe treatment option for the management of postoperative mucocele, maxillary sinusitis with narrow inlet, or benign tumors.

Evolutionary adaptation to aquatic lifestyle in extinct sloths can lead to systemic alteration of bone structure

Through phenotypic plasticity, bones can change in structure and morphology, in response to physiological and biomechanical influences over the course of individual life. Changes in bones also occur in evolution as functional adaptations to the environment. In this study, we report on the evolution of bone mass increase (BMI) that occurred in the postcranium and skull of extinct aquatic sloths. Although non-pathological BMI in postcranial skeleton has been known in aquatic mammals, we here document general BMI in the skull for the first time. We present evidence of thickening of the nasal turbinates, nasal septum and cribriform plate, further thickening of the frontals, and infilling of sinus spaces by compact bone in the late and more aquatic species of the extinct sloth Thalassocnus Systemic bone mass increase occurred among the successively more aquatic species of Thalassocnus, as an evolutionary adaptation to the lineage's changing environment. The newly documented pachyostotic turbinates appear to have conferred little or no functional advantage and are here hypothesized as a correlation with or consequence of the systemic BMI among Thalassocnus species. This could, in turn, be consistent with a genetic accommodation of a physiological adjustment to a change of environment.

Evolutionary adaptation to aquatic lifestyle in extinct sloths can lead to systemic alteration of bone structure

Through phenotypic plasticity, bones can change in structure and morphology, in response to physiological and biomechanical influences over the course of individual life. Changes in bones also occur in evolution as functional adaptations to the environment. In this study, we report on the evolution of bone mass increase (BMI) that occurred in the postcranium and skull of extinct aquatic sloths. Although non-pathological BMI in postcranial skeleton has been known in aquatic mammals, we here document general BMI in the skull for the first time. We present evidence of thickening of the nasal turbinates, nasal septum and cribriform plate, further thickening of the frontals, and infilling of sinus spaces by compact bone in the late and more aquatic species of the extinct sloth Thalassocnus Systemic bone mass increase occurred among the successively more aquatic species of Thalassocnus, as an evolutionary adaptation to the lineage's changing environment. The newly documented pachyostotic turbinates appear to have conferred little or no functional advantage and are here hypothesized as a correlation with or consequence of the systemic BMI among Thalassocnus species. This could, in turn, be consistent with a genetic accommodation of a physiological adjustment to a change of environment.

Regional deposition of nasal sprays in adults: A wide ranging computational study

The present work examines regional deposition within the nose for nasal sprays over a large and wide ranging parameter space by using numerical simulation. A set of 7 realistic adult nasal airway geometries was defined based on computed tomography images. Deposition in 6 regions of each nasal airway geometry (the vestibule, valve, anterior turbinate, posterior turbinate, olfactory, and nasopharynx) was determined for varying particle diameter, spray cone angle, spray release direction, particle injection speed, and particle injection location. Penetration of nasal spray particles through the airway geometries represented unintended lung exposure. Penetration was found to be relatively insensitive to injection velocity, but highly sensitive to particle size. Penetration remained at or above 30% for particles exceeding 10 μm in diameter for several airway geometries studied. Deposition in the turbinates, viewed as desirable for both local and systemic nasal drug delivery, was on average maximized for particles ranging from ~20 to 30 μm in diameter, and for low to zero injection velocity. Similar values of particle diameter and injection velocity were found to maximize deposition in the olfactory region, a potential target for nose-to-brain drug delivery. However, olfactory deposition was highly variable between airway geometries, with maximum olfactory deposition ranging over 2 orders of magnitude between geometries. This variability is an obstacle to overcome if consistent dosing between subjects is to be achieved for nose-to-brain drug delivery.

The Middle Turbinate Resection and Its Repercussion in Olfaction with the University of Pennsylvania Smell Identification Test (UPSIT)

Introduction  Nasal obstruction is a common complaint, and, for some, the middle turbinate resection is still a controversial issue among the surgical options due to the possibility of deleterious effects on olfaction. The University of Pennsylvania smell identification test (UPSIT) is considered the gold standard of smell identification tests, but data about it is still incipient in Brazil.

Objective  To evaluate if the middle turbinectomy has any repercussion on the sense of olfaction by using the UPSIT as an assessment tool.

Methods  A prospective study performed between 2013 and 2015 with 27 patients who were treated with middle turbinectomy by the same surgeon and tested with the UPSIT pre- and post-surgery, with a minimum interval of 3 months.

Results  Twenty-five patients completed the study. The mean age was 27.9 years. There was no statistical correlation between middle turbinectomy and the UPSIT score, or between gender and the UPSIT score.

Conclusion  There was no clinical repercussion on olfaction from partial middle turbinectomy.

Paranasal Sinus Anatomic Variations Accompanying Maxillary Sinus Retention Cysts: A Radiological Analysis

Objective

The risk factors for the development of retention cysts of the maxillary sinuses (RCMs) are not clear, although RCMs are common findings on radiographic images. This study was conducted to evaluate the correlation between RCMs and other nasal-paranasal anomalies and to demonstrate the possible effects of these anomalies on the development of RCMs.

Methods

In the study, paranasal sinus computerized tomography (PNsCT) images from 5166 patients were retrospectively reviewed. Correlations between RCMs and osteomeatal complex obstruction, accessory ostium presence, abnormalities of the middle turbinate, and nasal septal deviation were analyzed in the PNsCT images. The paranasal sinus anomalies on the side of the RCMs were compared to the contralateral side.

Results

A total of 1880 RCMs were detected in 1429 (27.6%) of 5166 patients. At least one nasal-paranasal sinus anomaly was associated with 88.7% of the RCMs. In the descending order, accessory ostium presence, accessory ostium, middle turbinate anomalies, and nasal septal deviation are pathologies that accompany RCMs. When unilateral RCMs were compared with the normal side, significant correlations were observed between RCMs and osteomeatal complex obstruction, accessory ostium, and middle turbinate anomalies (p=0.001, p=0.016, and p=0.03, respectively). RCMs were commonly found on the same side as osteomeatal complex obstruction (p=0.001), middle turbinate anomalies (p=0.001), and accessory ostium (p=0.052).

Conclusions

In this study, the coexistence of osteomeatal complex obstruction, accessory ostium, middle turbinate anomalies, and nasal septum deviation with RCMs was analyzed by investigating PNsCT findings in 5166 patients. The results show that RCMs are associated with pathologies that increase paranasal inflammation, such as osteomeatal complex obstruction, and are good markers for nasal-paranasal sinus anomalies. The presence of incidental RCMs should be a warning sign of nasal-paranasal sinus anomalies.

Eustachian Tube Dysfunction-Related Symptoms in Chronic Nasal Obstruction Caused by Inferior Turbinate Enlargement

OBJECTIVE

The aim of this study was to evaluate the relationship between chronic nasal obstruction caused by inferior turbinate enlargement and Eustachian tube dysfunction-related symptoms using the Eustachian Tube Dysfunction Questionnaire (ETDQ-7) as an assessment method.

METHODS

A total of 80 adults were enrolled. Group 1 comprised consecutive patients with enlarged inferior turbinates and group 2 comprised healthy controls. The ETDQ-7 scores and tympanometry results of both groups were analyzed and compared.

RESULTS

The median total scores of the ETDQ-7 in groups 1 and 2 were 1.9 (interquartile range, 1.4-2.8) and 1.1 (interquartile range, 1.0-1.7), respectively ( P < .001). There was no significant difference in the abnormal tympanometry results between the groups. There was no significant difference in the ETDQ-7 total score between the patients with allergic sensitization and other patients in group 1.

CONCLUSIONS

Patients with inferior turbinate enlargement have more symptoms related to Eustachian tube dysfunction than healthy controls. Most patients with Eustachian tube dysfunction had normal tympanometry and normal otoscopy, which indicates a baro-challenge-induced Eustachian tube dysfunction. Whether the patient has allergic sensitization or not does not seem to cause a difference in symptoms related to Eustachian tube dysfunction.

The supreme turbinate and the drainage of the posterior ethmoids: a computed tomographic study

BACKGROUND

It is generally acknowledged that the posterior ethmoidal cells drain under the superior nasal turbinate (SorNT) or, rarely, under the supreme nasal turbinate (SmeNT), and the sphenoid ostium (SO) opens to the sphenoethmoidal recess. However, detailed relations between these structures are variable, complex and still not clear. There is no reliable data on the prevalence of SmeNT and drainage of the posterior ethmoidal cells under this structure. The aim of this study was to re-evaluate the anatomy of the aforementioned region.

MATERIALS AND METHODS

Multiplanar and three-dimensional reconstruction analysis of 100 thin slice paranasal sinus computed tomography scans.

RESULTS

SmeNT was identified in 77 subjects (136 sides). It formed the ostium to the posterior ethmoidal cell adjacent to the skull base or orbit in 58 subjects (91 sides). This cell drained independently from the remaining posterior ethmoidal cells. The sphenoethmoidal (Onodi) cell drained to supreme meatus in 41 subjects (54 sides), and to superior meatus in 37 subjects (49 sides). SO was always located medial to the posteroinferior attachment of SmeNT, or SorNT (in absence of SmeNT).

CONCLUSIONS

Patients with divergent drainage of the posterior ethmoids (with posterior ethmoidal cell draining to the supreme meatus) may require more extensive surgery to avoid persistence or recurrence of inflammatory disease. SmeNT is more common than thought, but due to its posterior and superior location to SorNT, it is rarely seen intraoperatively. If SmeNT is present, SO is always located medial to its posteroinferior attachment. (Folia Morphol 2018; 77, 1: 110-115).

Computed Tomography Measurement of Inferior Turbinate in Asymptomatic Adult

Introduction  The inferior turbinate (IT) is the most susceptible turbinate to enlargement causing nasal obstruction. The common belief ascribes most of the enlargement of the IT to mucosal elements.

Objective  This study aimed to investigate the detailed computed tomography (CT) measurement of the IT in asymptomatic adult by determining the thickness of both the non-bony (mucosa) and bony parts and their relation to nasal air space in different related areas of the nose.

Methods  We included in the study paranasal CT scans of 108 individuals (216 IT) that had no paranasal pathology. We acquired axial images with multiplanar reformates to obtain delicate details in coronal and sagittal planes for all subjects. We took separate measurements of the thickness of the medial mucosa, bones, and lateral mucosa of the IT on the anterior and posterior portions of ITs. We also measured the air space of the nasal cavity between the septum and IT anteriorly and posteriorly.

Results  The difference in the air space between nasal septum, anterior and posterior ends of IT was extremely statistically significant (P < 0.0001). The thickness of the medial mucosa was extremely significantly more than the lateral mucosa width (P < 0.0001). There was no significant difference in length of IT at both sides ( p  = 0.5781).

Conclusion  The detailed CT measurement of the IT in normal adult is an easy and novel measurement. This study lays the foundation for CT measurement of IT for further work that can describe changes in IT measures after turbinate surgery.

Surgeon and hospital cost variability for septoplasty and inferior turbinate reduction

BACKGROUND

Septoplasty and turbinate reduction (STR) is a common procedure for which cost reduction efforts may improve value. The purpose of this study was to identify sources of variation in medical facility and surgeon costs associated with STR, and whether these costs correlated with short-term complications.

METHODS

An observational cohort study was performed in a multifacility network using a standardized cost-accounting system to determine costs associated with adult STR from January 1, 2008 to July 31, 2015. A total of 4007 cases, performed at 21 facilities, by 72 different surgeons were included in the study. Total costs, variable costs, operating room (OR) time, and 30-day complications (eg, epistaxis) were compared among surgeons, facilities, and specialties.

RESULTS

Total procedure cost: (mean ± standard deviation [SD]) $2503 ± $790 (range, $852 to $10,559). Mean total variable cost: $1147 ± $423 (range, $400 to $5,081). Intersurgeon and interfacility variability was significant for total cost (p < 0.0001) and OR time (p < 0.0001). Intersurgeon OR supply cost variability was also significant (p < 0.0001). Otolaryngologists had less total cost (p < 0.0001), OR time/cost (p < 0.0001), and complications (p = 0.0164), but greater supply cost (p < 0.0001), than other specialties.

CONCLUSION

There is wide variation in cost associated with STR. Significant variance in OR time and supply cost between surgeons suggests these are potential areas for cost reduction. Although no increased 30-day complications were seen with faster and less costly surgeries, further research is needed to evaluate how time and cost relate to quality of care.

[Polyp within massive concha bullosa: a case report]

To discuss the complication of common anatomic variant of the middle turbinate-concha bullosa. We present a 63 years old man with nasal obstruction who was diagnosed to be a polyp originated from concha bullosa by CT and operation. Polyp originated from middle meatus was squeezed into concha bullosa. Endoscopic operation is the best treatment to this disesase. Concha bullosa can result in obstruction of middle meatus and then lead to sinusitis. This case, polyp originated from middle meatus was squeezed into concha bullosa, it was a rare occurrence.

Surgical Treatment of Rhinogenic Contact Point Headache: An Experience from a Tertiary Care Hospital

Introduction Even in the absence of inflammatory disease, facial pain often results from pressure of two opposing nasal mucosa surfaces. Objectives The objective of this study is to assess the efficacy of surgical treatment of contact point headache. Methods Our study enrolled patients with unilateral facial pain and without nasal/paranasal sinus disease. We confirmed the presence of mucosal contact by nasal endoscopy and by computed tomography. Forty-two subjects with the three most common anatomical variations underwent complete evaluation: 17 with concha bullosa (CB), 11 with septal deviation (SD), and 14 with septal spur (SS). All participants were treated by topical corticosteroid, adrenomimetic, and antihistamine. The patients without improvement were treated surgically. We assessed the severity of pain using a Visual Analogue Score (VAS) before surgical treatment and one, six, twelve, and twenty-four months after. Results The patients with SS had more severe facial pain in comparison with patients with CB (p = 0.049) and SD (p = 0.000). The subjects with CB had higher degree of facial pain than the ones with SD (p = 0.001). After an unsuccessful medical treatment and surgical removal of mucosal contacts, the decrease of headache severity was more intense in patients with CB and SS (p = 0.000) than in the patients with SD (p = 0.01). Conclusion Our results suggest that topical medications have no effects and that surgical removal of mucosal contacts could be effective in the treatment of contact point headache. The results of surgical treatment were better in cases of facial pain caused by SS and CB, than in those caused by SD.

Tour of a labyrinth: exploring the vertebrate nose

This special issue of The Anatomical Record is the outcome of a symposium entitled "Inside the Vertebrate Nose: Evolution, Structure and Function." The skeletal framework of the nasal cavity is a complicated structure that often houses sinuses and comprises an internal skeleton of bone or cartilage that can vary greatly in architecture among species. The nose serves multiple functions, including olfaction and respiratory air-conditioning, and its morphology is constrained by evolution, development, and conflicting demands on cranial space, such as enlarged orbits. The nasal cavity of vertebrates has received much more attention in the last decade due to the emergence of nondestructive methods that allow improved visualization of the internal anatomy of the skull, such as high-resolution x-ray computed tomography and magnetic resonance imaging. The 17 articles included here represent a broad range of investigators, from paleontologists to engineers, who approach the nose from different perspectives. Key topics include the evolution and development of the nose, its comparative anatomy and function, and airflow through the nasal cavity of individual species. In addition, this special issue includes review articles on anatomical reduction of the olfactory apparatus in both cetaceans and primates (the vomeronasal system), as well as the molecular biology of olfaction in vertebrates. Together these articles provide an expansive summary of our current understanding of vertebrate nasal anatomy and function. In this introduction, we provide background information and an overview of each of the three primary topics, and place each article within the context of previous research and the major challenges that lie ahead.

Breathing life into dinosaurs: tackling challenges of soft-tissue restoration and nasal airflow in extinct species

The nasal region plays a key role in sensory, thermal, and respiratory physiology, but exploring its evolution is hampered by a lack of preservation of soft-tissue structures in extinct vertebrates. As a test case, we investigated members of the "bony-headed" ornithischian dinosaur clade Pachycephalosauridae (particularly Stegoceras validum) because of their small body size (which mitigated allometric concerns) and their tendency to preserve nasal soft tissues within their hypermineralized skulls. Hypermineralization directly preserved portions of the olfactory turbinates along with an internal nasal ridge that we regard as potentially an osteological correlate for respiratory conchae. Fossil specimens were CT-scanned, and nasal cavities were segmented and restored. Soft-tissue reconstruction of the nasal capsule was functionally tested in a virtual environment using computational fluid dynamics by running air through multiple models differing in nasal soft-tissue conformation: a bony-bounded model (i.e., skull without soft tissue) and then models with soft tissues added, such as a paranasal septum, a scrolled concha, a branched concha, and a model combining the paranasal septum with a concha. Deviations in fluid flow in comparison to a phylogenetically constrained sample of extant diapsids were used as indicators of missing soft tissue. Models that restored aspects of airflow found in extant diapsids, such as appreciable airflow in the olfactory chamber, were judged as more likely. The model with a branched concha produced airflow patterns closest to those of extant diapsids. These results from both paleontological observation and airflow modeling indicate that S. validum and other pachycephalosaurids could have had both olfactory and respiratory conchae. Although respiratory conchae have been linked to endothermy, such conclusions require caution in that our re-evaluation of the reptilian nasal apparatus indicates that respiratory conchae may be more widespread than originally thought, and other functions, such as selective brain temperature regulation, could be important.

Radiofrequency Thermal Ablation versus Bipolar Electrocautery for the Treatment of Inferior Turbinate Hypertrophy: Comparison of Efficacy and Postoperative Morbidity

Introduction Numerous surgical methods are used to treat nasal obstruction due to inferior turbinate hypertrophy. The primary goal of the therapy is to maximize the nasal airway for as extended a period of time as possible while minimizing therapeutic complications. Objectives The aim of this study was to assess the effects of radiofrequency thermal ablation (RFTA) and bipolar electrocautery (BEC) on the removal of nasal obstruction in patients with inferior turbinate hypertrophy and on nasal mucociliary clearance (MCC). Patients in both groups were also evaluated in terms of postoperative morbidity. Methods We compared the outcomes of two groups of patients: those treated with RFTA (n = 23) and those who underwent BEC (n = 20). Nasal obstruction was graded using a visual analog scale (VAS) and MCC was measured using a saccharin clearance test. Both measurements were performed before and 2 months after treatment. Results Pre- and postoperative VAS scores showed significant improvement for both groups. However, MCC results did not significantly differ between two groups. Neither edema nor crust formation persisted for more than 1 week in any patients. Conclusion Submucosal cauterization with preservation of the nasal mucosa and periosteum is as effective and safe as RFTA and should be considered when planning inferior turbinate interventions.

An anatomically based analysis of objectively measured pediatric snoring: a pilot study

OBJECTIVE

To assess pediatric habitual snoring (PS) using home sleep test (HST) technology and attempt to correlate the objective components of PS to specific upper airway anatomy. In addition, the effects of adenotonsillectomy (±turbinoplasty) on objective measures of PS were evaluated.

STUDY DESIGN

Prospective cohort study.

SETTING

Tertiary medical center.

SUBJECTS AND METHODS

Pediatric patients with a chief complaint of snoring and probable obstructive sleep apnea underwent an HST (SNAP Diagnostics, Wheeling, Illinois) with a detailed acoustical snoring analysis prior to adenotonsillectomy (±turbinoplasty). During surgery, detailed anatomical measurements were performed and correlated to snoring analysis results. After surgery, patients were offered another HST with snoring analysis. Data analysis was performed using descriptive statistics and statistical correlation with attention to the multiple-comparisons paradox.

RESULTS

Twenty-two patients (45% male; mean age, 5.4 years [range, 2.4-8.4 years]) completed the preoperative HST and operative measurements. Unlike typical adult snoring, only a minority of PS was from palatal flutter (mean palatal component, 24%; median, 10%). The resistance occurrence percentage (ROP, percentage of breathing events with snoring noise) was associated with body mass index (BMI; Spearman ρ=0.55; P=.017), subjective turbinate size (0.54; P=.032), palatal obstruction (0.63; P=.008), and mean oxygen saturation (-0.729; P=.0003) but not adenotonsillar hypertrophy. Twelve patients (54%) completed a postoperative HST. The ROP was significantly reduced (median, 20.5% vs 6.5%; P=.006, sign rank test) postoperatively. The magnitude of the ROP reduction was proportional to the volume of the removed tonsils (0.74; P=.022).

CONCLUSION

Pediatric snoring has different acoustical characteristics than adult snoring. Objective PS is associated with BMI, turbinate size, and palatal obstruction. Adenotonsillectomy (±turbinoplasty) may significantly reduce objective PS.