Influence of nasal septum deviation on fluctuating asymmetries of the nasomaxillary complex: A cross-sectional study.

An important parameter in diagnostic analysis and treatment planning of different biological areas is facial symmetry, and several etiological factors have been attributed to skeletal facial asymmetry. Although causality cannot be determined, previous studies have reported a relationship between the anatomical deviation of the nasal septum and facial development. Diagnosis is critical for patients in growth stages due to the association between nasal septum deviation (NSD) and abnormal growth of the nasomaxillary complex. To understand this relationship, this study aimed to investigate the influence of nasal septum deviation on fluctuating asymmetries (FA) of the nasomaxillary complex at different stages of skeletal maturation. Another goal was to determine whether an association exists between the degrees of septal deviation severity and asymmetry of the nasomaxillary complex. This was a retrospective, cross-sectional observational study comprising 60 selected cone-beam computed tomography (CBCT) scans that were divided into four groups (n = 15) according to the degree of septal deviation and skeletal maturation: mild deviation (MD; <10°), moderate to severe deviation (MSD; ≥10°), early group (EG), and late group (LG). The angle and area of deviation were measured for the greatest NSD, and a geometric morphometric approach was used to evaluate the nasal septum (NS) shape. The morphology of the nasomaxillary complex and the presence of fluctuating asymmetries were evaluated using 23 two-dimensional landmarks on the nasomaxillary complex (nasal, lateral, and palatal regions) with Procrustes ANOVA and Mann-Whitney test. Additionally, Spearman's correlation and multivariate regression were used to correlate the NSD with asymmetries in these regions. No significant differences were observed in the Procrustes FA scores of the nasomaxillary complex between the MD-EG × MSD-EG and MD-LG × MSD-LG (p > 0.05). However, the results of the multivariate regression revealed more specific aspects of asymmetry (asymmetry component), there was a positive correlation between the NSD angle and the palatal regions (p = 0.035 and p = 0.047, middle and posterior, respectively), and the nasal septum shape and anterior palatal regions (p = 0.039). The nasal and lateral regions did not correlate with the NSD angle in the multivariate regression analysis (p > 0.05). The results of this study indicate that there were no significant differences in the fluctuating asymmetry of the nasomaxillary complex between the mild and moderate to severe nasal septum deviation groups, in both early and late skeletal maturation stages. However, a positive correlation was observed in the degree of nasal septum deviation angle and asymmetry components of the middle and posterior palatal regions, likewise between the nasal septum shape and asymmetry components of the anterior palatal region. The diagnosis of nasal septum deviation by both physicians and dentists is important, as a relationship was observed with fluctuating asymmetry component of the palatal region. This information can guide the decision of the treatment planning for these individuals, and should be considered, especially in cases of severe septum deviation, due to the great anatomical proximity of these structures.

Lack of impact of radiologic septal measurements upon patient symptoms and performance of septoplasty during endoscopic sinus surgery.

BACKGROUND: Recent literature suggests that concurrent septoplasty during endoscopic sinus surgery (ESS) improves patient outcomes, however, the underlying indications for performing concurrent septoplasty are unknown. The objective of this study was to investigate the relationship between objective radiologic measures of nasal septal deviation with preoperative patient symptomatology and measures of CRS disease severity. We also sought to understand the association of objective radiologic measurements with surgeon performance of concurrent septoplasty during ESS. METHODOLOGY: Seventy-four patients with CRS undergoing ESS were prospectively enrolled. Angles of septal deviation, intranasal areas and volumes were assessed on preoperative computed tomography (CT) scans and correlated with a robust battery of patient reported outcomes measures (PROMs), objective measures of CRS severity including olfaction scores, radiologic and endoscopic staging, and performance of septoplasty. RESULTS: Intranasal areas and volumes demonstrated only weak linear associations with patient-reported nasal congestion, however, angles of septal deviation alone did not correlate with congestion or any other PROM measure. Meanwhile, radiologic septal-related measurements did not correlate with objective measures of CRS disease severity or the performance of a concurrent septoplasty. CONCLUSIONS: Though prior studies demonstrate improved patient outcomes in the setting of concurrent septoplasty during ESS, this study failed to establish an association between preoperative radiologic septal-related measurements and patient symptomatology or surgeon decision to perform septoplasty. Although objective factors to identify patients most likely to benefit from concurrent septoplasty remain unidentified, the potential improvement of surgical recommendations and patient outcomes makes this an important area of continued investigation.

Canine nasal septum deviation can be a normal variation and correlates with increasing skull indices.

Nasal septal deviation has been studied in relation to nasal pathology and mass effect in dogs. The purpose of this retrospective, cross-sectional study was to compare the prevalence of nasal septal deviation in dogs with rhinitis, neoplasia, and those without nasal pathology based on the facial index, skull index, and cranial index. Computed tomographic studies of the nasal cavities of dogs performed over a 5-year period were retrospectively reviewed. This study had 233 dogs meeting the inclusion criteria with 135 dogs with no nasal pathology, 63 dogs with nasal neoplasia, and 35 dogs with rhinitis. The prevalence of nasal septal deviation, the angle, maximum distance, and longitudinal extent of deviation were recorded, as well as measurements to calculate the facial index, cranial index, and skull index. The results showed no difference in the prevalence of nasal septal deviation between dogs with nasal pathology and those without. The mean longitudinal extent of deviation and maximum distance of deviation was statistically greater for those with neoplasia compared to those with rhinitis and without nasal pathology. The longitudinal extent of deviation was inversely proportional to the cranial index, facial index, and skull index. The angle of deviation was directly proportional to the facial index and skull index. In conclusion, nasal septal deviation is an anatomic variant in different breeds of dogs with no predilection based on nasal pathology. Nasal septal deviation should be interpreted cautiously in the assessment of canine nasal disease.

Evaluation of the Relationship of Dimensions of Maxillary Sinus Drainage System with Anatomical Variations and Sinusopathy: Cone-Beam Computed Tomography Findings.

OBJECTIVE: The aim of this study was to evaluate the correlation between the length of the infundibulum and ostium height with the anatomic variations of osteomeatal complex (OMC) and sinus pathology using cone-beam computed tomography (CBCT). METHODS: CBCT images of 204 patients (408 maxillary sinuses) were evaluated retrospectively. The height of the ostium and the length of the infundibulum were measured. The presence of maxillary sinus pathology, nasal septal deviation, Haller cells, concha bullosa, and sinus septa were analyzed. The correlation between the size of the maxillary sinus drainage system and anatomic variations was compared using the t test, Fisher's exact test, and χ2 test. The effect of tooth loss on the length of the infundibulum and ostium height was also analyzed using ANOVA. RESULTS: The height of the ostium and the maximal septal deviation angle were found to be significantly greater in males (p < 0.05). As ostium height increased, the presence of maxillary sinus septa increased (p < 0.05). No statistically significant association was detected between other variations and the length of infundibulum or ostium height. The relationship between tooth loss and both the length of the infundibulum and ostium height were found to be insignificant (p > 0.05). CONCLUSIONS: Radiographic examination, especially on CBCT images, is important for an evaluation of maxillary sinuses. here, we demonstrated a significant relationship between ostium height and the presence of maxillary sinus septa. However, it was found that nasal septal deviation, concha bullosa, Haller cells, and other sinusopathies did not have a major effect on the size of the maxillary sinus drainage system.

Geometric morphometric contribution to septal deviation analysis.

PURPOSE: The nasal septum presents inter-individual conformational variations. The objectives of this study were to establish a validated protocol for nasal septum analysis using geometric morphometrics (GM) to establish a classification of septal deviations (SD). METHODS: This was a retrospective study including two groups of patients: patients operated on by septoplasty (SD group) and patients without nasal obstruction (control group). The 3D segmentation model was extracted from CT scans. Thirty landmarks were defined on the nasal septum and validated by MANOVA Procrustes. Using a clusterization process, the septum was classified to reflect its different conformations. Nasal resistances were compared between the two groups. RESULTS: Fifty scans of patients with SD were included. The percentage of variability due to measurement error was 7.9% across all landmarks. We identified two clusters for the SD group. Using GM, conformation of cluster 1 (S-shaped) and cluster 2 (C-shaped) was visualized and identified. There was a statistically significant difference regarding nasal resistance between each cluster in the SD group compared with the control group (p < 0.05). CONCLUSIONS: This work is a first step in SD exploration, contributing to a clearer appreciation of the interactions between nasal conformation and function. An SD classification was devised based on a reliable and reproducible statistical analysis. Enhanced understanding of conformation/function interactions will improve the diagnosis and treatment of nasal obstruction.

Anatomical Study of the Chinese Nasal Keystone Region.

BACKGROUND: The keystone region is an important anatomical structure to consider in rhinoseptoplasty, because there are few published data regarding the keystone region in Chinese noses. OBJECTIVES: The authors sought to describe the anatomy of the Chinese nasal keystone region and provide useful knowledge for rhinoseptoplasty. METHODS: Sixteen cadaveric heads (11 males, 5 females) were dissected, measured, and then compared with previously published data. RESULTS: Both the nasal bone caudal margin and nasal bone-upper lateral cartilage overlapping area displayed 5 distinct shapes, and the upper lateral cartilage showed 4 distinct shapes. The nasal bone-upper lateral cartilage overlap was 6.47 mm ± 2.50 in the midline, 3.53 mm ± 2.23 on the left, and 3.81 mm ± 2.56 on the right. The length of the whole quadrangular cartilage was 25.63 mm ± 4.27; 25% ± 8% was overlapped by the nasal bone. The height of the caudal quadrangular cartilage was 18.14 mm ± 3.44, and the width of the nasal bone-upper lateral cartilage articulation was 23.56 mm ± 8.30. The upper lateral cartilage-quadrangular cartilage complex stayed in position on the maxillary crest and nasal spine, even after being dissected from the nasal bone, perpendicular plate of the ethmoid bone, and vomer. Bilateral perichondrial-periosteal mucosa detached from the nasal septum. CONCLUSIONS: We report various anatomical and structural features of the Chinese keystone region, which will be valuable for rhinoseptoplasty planning in Chinese patients.

Minimal Clinically Important Difference of the Standardized Cosmesis and Health Nasal Outcomes Survey.

BACKGROUND: The minimal clinically important difference (MCID) for the Standardized Cosmesis and Health Nasal Outcomes Survey (SCHNOS) has not been determined. OBJECTIVES: The authors sought to define the MCID for both domains of the SCHNOS questionnaire. METHODS: This prospective cohort study included patients who underwent functional, cosmetic, or combined rhinoplasty operation from June 2017 to June 2018 at a tertiary referral center. The average preoperative, postoperative, and change in scores were calculated for the nasal obstruction symptom evaluation scale (NOSE) and SCHNOS. Anchor-based MCIDs were estimated for both SCHNOS subscales to define change in obstruction and cosmesis perceived after the rhinoplasty. RESULTS: Eighty-seven patients (69% women, 31% males) with a mean age (standard deviation [SD]) of 38 years (14.7) at the time of surgery were included. The mean postoperative follow-up period (SD) was 145 days (117). The mean preoperative score (SD) for the NOSE was 52 (32), SCHNOS for nasal obstruction (SCHNOS-O) score was 55 (33), and SCHNOS for nasal cosmesis (SCHNOS-C) score was 50 (26) points. Postoperatively, the NOSE score was 23 (22), SCHNOS-O score was 24 (23), and SCHNOS-C score was 13 (18) points. The mean change in scores (SD) for NOSE, SCHNOS-O, and SCHNOS-C was -29 (37), -31 (38), and -37 (28), respectively. The calculated MCID for SCHNOS-O was 26 (16) and for SCHNOS-C was 22 (15) points. The MCID for NOSE was 24 (13) points. A sensitivity test for the patients with a follow-up ≥3 months showed only slightly different MCID estimates: 28 (17) for SCHNOS-O, 18 (13) for SCHNOS-C, and 24 (15) points for NOSE. CONCLUSIONS: For the obstruction domain SCHNOS-O, the MCID was 28 points. For the cosmetic domain SCHNOS-C, the MCID was 18 points.

Computed tomography analysis of intranasal distance of frontal and sphenoid sinus ostiums in children.

PURPOSE: Pediatric population may be more prone to complications in comparison to adults because of the variability of developmental changes of paranasal sinuses and skull base. Knowledge of standard columellar distances regarding age in addition to anatomical landmarks is an important guide during functional endoscopic sinus surgery. We aimed to identify standard distances from columella and anterior nasal spine to the anterior and posterior border of frontal and sphenoid sinus ostiums and provide an objective reference graph in regard to age in children. METHODS: Subjects who are older than 1 year and younger than 18 years who had undergone a head-and-neck, maxillofacial or temporal bone region high resolution computed tomography scan during the last 3 years were obtained from radiological database. The distances from columella and anterior nasal spine to the anterior and posterior border of frontal and sphenoid sinus ostiums were measured and nasofrontal and nasosphenoid angles were calculated. RESULTS: A total number of 119 children (73 boys, 46 girls) were reviewed. The average age was 7.7 ± 5.0 years. All subjects had normal sinonasal anatomy. We found statistically significantly positive correlation between age and all distances (p < 0.001). Although all measured distances of boys were greater than girls, this difference did not reach statistical significance. Additionally, nasosphenoidal angles were significantly obtuse in boys (p < 0.05). CONCLUSIONS: Our columellar distance graphic can provide further improvement of surgeon confidence while performing endoscopic sinus surgery or skull base surgery.

Functional anatomy of the nasal bones and adjacent structures. Consequences for nasal surgery.

The periosteum of the nasal bones, the periosteal-perichondrial nasal envelope, and the cartilaginous support of the bony vault were studied in serial coronal sections of four human cadaver noses. To differentiate between the various tissue components, the sections were stained according to Mallory-Cason and Verhoeff-Van Gieson stain. The results demonstrated: 1. the presence of clearly distinguishable layers of the periosteum covering the nasal bones; 2. the presence of a continuous periosteal-perichondrial covering of the bony and cartilaginous nasal vaults; 3. the way the cartilaginous support of the bony vault is constructed. The findings described in the present study may have clinical relevance in nasal surgery.

Surgical Tips for the Management of the Wide Nasal Base.

Alar base reduction (ABR) was first described by Weir in 1892, but continues to be a controversial topic in rhinoplasty in terms of optimal techniques. The authors describe the techniques for ABR including internal, external and combined ABR, flare excisions, and alar hooding reductions. The techniques described have resulted in consistent outcomes with acceptable scarring and high patient satisfaction.

Dorsal Preservation: The Push Down Technique Reassessed.

Management of the nasal dorsum remains a challenge in rhinoplasty surgery. Currently, the majority of reduction rhinoplasties results in destruction of the keystone area (K-area), which requires reconstruction with either spreader grafts or spreader flaps, both for aesthetic and functional reasons. This article will present the senior author's current operative technique for dorsal preservation in reduction rhinoplasty based on 320 clinical cases performed over a 5-year period. The author's operative technique is as follows: (1) endonasal approach; (2) removal of a septal strip in the subdorsal area whose shape and height were determined preoperatively; (3) complete lateral, transverse, and radix osteotomies; and (4) dorsal reduction utilizing either a push down operation (PDO) or a let down operation (LDO). The PDO consists of downward impaction of the fully mobilized nasal pyramid and is utilized in patients with smaller humps (Less than 4 mm). The LDO consists of a maxillary wedge resection and is performed in patients who need more than 4 mm of lowering. A total of 320 patients had a dorsal preservation operation (DPO). Postoperatively, there were no dorsal irregularities nor inverted-V deformities. Among our 44 personal revision cases, 27 patients (8.74%) had had a previous DPO, 16 of whom required tip revisions with no further dorsal surgery. Of the remaining 11 patients, the main problems were either hump recurrence and/or lateral deviation of the dorsum or widening of the middle third, which required simple surgical revision. Based on the authors' experience, adoption of a PDO/LDO is justified in selected primary patients. The key question before any primary rhinoplasty procedure should be "Can I keep the nasal dorsum intact?" Precise analysis and surgical execution are required to preserve the dorsal osseocartilaginous vault and K-area. Dorsal preservation results in more natural postoperative dorsum lines and a "not operated" aspect without the need for midvault reconstruction. Moreover, this technique is quick and easy to perform by any rhinoplasty surgeon. Rhinoplasty surgeons should consider incorporating dorsal preservation techniques in their surgical armamentarium rather than relying solely on the Joseph reduction method or an open structure rhinoplasty.

Effects of the Tongue-in-Groove Maneuver on Nasal Tip Rotation.

BACKGROUND: A change in nasal tip rotation is a very common maneuver performed during rhinoplasty. Among the many techniques used to achieve this goal is the tongue-in-groove (TIG). OBJECTIVES: This study addresses the long-term effect of the TIG on the nasal tip rotation 1 year after rhinoplasty. METHODS: The authors prospectively identified patients who were submitted to a rhinoplasty with a TIG maneuver over a period of 1 year. The angle of rotation was measured along the nostril axis angle. The data were analyzed using the t test and a linear regression model. RESULTS: Seventeen patients were included. The average preoperative tip rotation was 93.95° (SD, 3.12°). Immediate postoperative tip rotation averaged 114.47° (SD, 3.79°). At the 1-year follow-up appointment, the tip rotation averaged 106.55° (SD, 3.54°). There was a significant loss of rotation at the 1-year postoperative visit (P < 0.0001), with an average loss of 7.9° (SD, 3.25°), which amounted to 6.8%. The preoperative rotation didn't affect the amount of loss of rotation (P = 0.04). It can be estimated that, for every degree of rotation that is changed at surgery, the tip can be expected to lose 0.35 degrees over the first year. CONCLUSIONS: TIG is a more dependable technique than the ones that rely on healing and contraction to obtain rotation. Our data demonstrated a significant loss of rotation during the first year. This suggests that the surgeon needs to slightly overcorrect the tip rotation to account for this loss.

The Caucasian Nasal Septum: An In Vivo Computed Tomography Study.

BACKGROUND: The nasal septum is composed of cartilaginous and bony components and an understanding of each component volume is essential in both functional and cosmetic surgery. OBJECTIVES: We sought to radiographically measure septal dimensions on cross sectional computer tomography (CT) images, establishing average parameters for normal anatomy among a single, Caucasian population group. METHODS: One hundred and fifty consecutive sinus CT scan images were examined and 100 cases with appropriate sagittal views were included in the study. On each septum, the sagittal CT images were assessed and 14 points were identified and 23 lengths measured and tabulated. Trigonometric formulae were used to accurately calculate surface areas of 11 resulting triangles which constituted the components of the nasal septum. RESULTS: Measurements from 100 patients were included, with a mean age of 50.2 years, constituting 47 males and 53 females. Our surface area mapping established the following areas for both males and females respectively (mm2): quadrangular cartilage 1148 and 981; vomer 894 and 741; perpendicular plate of ethmoid bone 1244 and 1006; and total surface area 3287 and 2728. Our only statistically significant comparison in the series was found in the female series when age and reducing quadrilateral cartilage size were compared, highlighting reducing size with age (P = 0.04). CONCLUSIONS: The study presents the largest published data series representing nasal septal measurements on CT images in a living Caucasian population. Our data demonstrates that septal size remains constant after adolescence, throughout our age-varied series (18-79 years), except in the female population where the quadrilateral cartilage reduces in size with age.

Morphological interaction between the nasal septum and nasofacial skeleton during human ontogeny.

The nasal septal cartilage is thought to be a key growth center that contributes to nasofacial skeletal development. Despite the developmental influence of the nasal septum however, humans often exhibit a high frequency of septal deviation suggesting discordance in the growth between the septum and surrounding nasofacial skeleton. While there are numerous etiological factors that contribute to septal deviation, the surrounding nasofacial skeleton may also act to constrain the septum, resulting in altered patterns of growth. That is, while the nasal septum has a direct morphogenetic influence on aspects of the nasofacial skeleton, other nasofacial skeletal components may restrict septal growth resulting in deviation. Detailing the developmental relationship between these structures is important not only for understanding the causal determinants of nasal septal deviation, but also for developing a broader understanding of the complex interaction between the facial skeleton and chondrocranium. We selected 66 non-syndromic subjects from the University of Minnesota Orthodontic Clinic who ranged from 7 to 18 years in age and had an existing pretreatment cone-beam computed tomography (CBCT) scan. Using CBCT data, we examined the developmental relationship between nasal septal deviation and the surrounding nasofacial skeleton. We measured septal deviation as a percentage of septal volume relative to a modeled non-deviated septum. We then collected a series of coordinate landmark data in the region immediately surrounding the nasal septum in the midsagittal plane representing the nasofacial skeleton. First, we examined ontogenetic changes in the magnitude of nasal septal deviation relative to chronological age and nasofacial size. Next, using Procrustes-based geometric morphometric techniques, we assessed the morphological relationship between nasal septal deviation and nasofacial skeletal shape. Our results indicate that variation in the magnitude of nasal septal deviation was established in our earliest age group and maintained throughout ontogeny. Moreover, nasal septal deviation was correlated with non-allometric variation in nasofacial shape restricted to the region of the anterior sphenoid body. Ultimately, our results suggest that early developmental variation in midline basicranial components may act to alter or constrain patterns of nasal septal growth.

Nasal obstructive disorders induce medical treatment failure in paediatric persistent allergic rhinitis (The NODPAR Study).

BACKGROUND: Allergic rhinitis (AR) is the most common chronic disease among children. To characterize the disease, a modified classification of severity (m-ARIA) has recently been validated in AR children. When medical treatment fails, surgery for nasal obstructive disorders (NOD) may be a therapeutic option. Our objective was to assess the prevalence of NOD and their influence in medical treatment response among children with persistent AR (PER). METHODS: In a prospective, real-life study, 130 paediatric PER patients (13.1 ± 2.8 years, females 31.5%, severe rhinitis 49%) referred from Allergy to ENT department were assessed for their response (R, responders; NR, non-responders) to medical treatment (intranasal steroids and antihistamines or antileukotrienes) by direct questioning and nasal symptom visual analogue scale, the presence of NOD (septal deformity, turbinate enlargement and adenoidal hyperplasia), comorbidities, nasal symptoms, rhinitis severity (modified ARIA criterion) and asthma control (International Consensus On Pediatric Asthma criterion). RESULTS: After 2 months of treatment, the NR group presented a higher prevalence of obstructive septal deformity and severe inferior turbinate enlargement when compared with the R group. Higher septal deformity and turbinate enlargement scores were strongly associated with treatment refractoriness. The prevalence of severe PER was also higher for the NR group. Higher asthma control scores were associated with the probability of treatment-induced improvement. CONCLUSIONS: In paediatric PER patients, medical therapy refractoriness was associated with NOD, mainly septal deformity and turbinate enlargement. In those patients, ENT examination will facilitate an early NOD diagnosis in order to indicate potential corrective surgery.

Nasal septum configuration as a basis for novel septal splints.

The objective is to use anatomical determinations of nasal septum shape and surface area in adults as a design basis for silastic septal splints of universal size and fit and offering maximum possible surface coverage. The objective is also to devise a method of securing the septal splints, so that surface pressure on septal mucosa is distributed as evenly as possible while not interfering with capillary perfusion. Nasal septum area was determined in 21 Caucasian body donors, and nasal septum thickness was measured in 20 CT scans. Septal splints of universal size and shape were prepared from silastic sheeting. The holding force of various neodymium-iron-boron (NdFeB) magnets, and the surface pressure exerted by magnet-containing septal splints was calculated. These septal splints of novel design offer a satisfactory fit in routine clinical practice. The splints can be securely attached with built-in NdFeB magnets, and surface pressure can be distributed evenly across the nasal septum while not interfering with mucosal tissue perfusion. With their simple intranasal insertion, these magnet-containing septal splints of universal size and optimised shape offer maximum possible septum coverage following septoplasty/septorhinoplasty. The absence of interference with septal tissue perfusion means that they are likely to be associated with fewer postoperative complications and better outcomes.

Sinus septi nasi: Anatomical study.

The aim of this study was to perform a pioneering investigation into the incidence of pneumatization in human skulls. A total of 93 human skulls (≥20 years of age, 69 males, 24 females) were included in the study. The skulls were scanned in a fixed position using cone beam computed tomography (CBCT). The pneumatized space parameters within the nasal septum-width, length, and height-were measured. Two types of finding were identified: (a) Pneumatization, named "sinus septi nasi" (SSN), and (b) "spongy bone" (SB). The results showed SSN in 32 of the 93 skulls (34.4%). The SSN formations were from 0.5 to 4.2 mm wide, 3.5 to 18.8 mm long, and 3.8 to 17.7 mm high. Tumefactions filled with SB were found in 61 of the 93 skulls (65.59%). These were not suitable for precise measurements since the outer borders were not strictly and well defined on CT scans (perhaps because of the preparation process). In conclusion, the perpendicular plate of the ethmoidal bone is not always compact bone; in 34.4% of cases, it shows a degree of pneumatization. In contrast, an enlarged formation filled with SB is present in 65.59% of cases. The possible sources of pneumatization of this little-investigated region are discussed: sphenoid sinus, frontal sinus, and vomeronasal organ. Clin. Anat. 30:312-317, 2017. © 2017 Wiley Periodicals, Inc.

Structure and function of the septum nasi and the underlying tension chord in crocodylians.

A long rostrum has distinct advantages for prey capture in an aquatic or semi-aquatic environment but at the same time poses severe problems concerning stability during biting. We here investigate the role of the septum nasi of brevirostrine crocodilians for load-absorption during mastication. Histologically, both the septum nasi and the septum interorbitale consist of hyaline cartilage and therefore mainly resist compression. However, we identified a strand of tissue extending longitudinally below the septum nasi that is characterized by a high content of collagenous and elastic fibers and could therefore resist tensile stresses. This strand of tissue is connected with the m. pterygoideus anterior. Two-dimensional finite element modeling shows that minimization of bending in the crocodilian skull can only be achieved if tensile stresses are counteracted by a strand of tissue. We propose that the newly identified strand of tissue acts as an active tension chord necessary for stabilizing the long rostrum of crocodilians during biting by transforming the high bending stress of the rostrum into moderate compressive stress.

Morphological Patterns and Variations of the Nasal Septum Components and Their Clinical Implications.

The aim of this study was to clarify the morphological patterns and proportions of the components of the nasal septum. Anatomical examinations were performed on 70 nasal septums of embalmed Korean adult cadavers. The septal deviation was checked before cutting the nasal cavity midsagittally with the aid of a laryngoscope. The shape of each component of the nasal septum was identified, and photographs were taken from a midline sagittal view. A line was drawn on each photograph between the septal components, and then the area of each septal component was measured using software. The mean area proportions of the septal cartilage (SC), the perpendicular plate of the ethmoid bone (PPE), the vomer, and the nasal crest of the maxilla relative to the total area of the nasal septum were 25.6%, 43.0%, 25.8%, and 5.6%, respectively. The morphology of the nasal septum was classified into 3 main patterns according to the proportion of each septal component. The proportions of the SC, the PPE, the vomer, and the nasal crest of the maxilla were similar to the mean values of the present study in 45.7%. The proportions of the SC, the PPE, and the vomer were similar to each other (with a difference of <15%) in 24.3%. The proportion of the PPE exceeded 50% of the total area of the nasal septum in 22.9%. The results reported herein provide detailed anatomical knowledge that can be used as a valuable reference for rhinoplasty procedures.

The Significance of Rhinologic Evaluation and Pretreatment for Patients Undergoing Two-Jaw Surgery Through Nasotracheal Intubation.

The aim of this study is to determine whether rhinologic preoperative evaluation and pretreatments reduce intranasal trauma and decrease postoperative complications, such as nasal obstruction and epistaxis, in patients undergoing 2-jaw surgery with nasotracheal intubation. This study included 360 patients with malocclusion (Class III) who underwent 2-jaw surgery under general anesthesia via nasotracheal intubation in our hospital from January to December 2013 and categorized into 3 groups. Nasotracheal intubation was performed according to the nasal cavity the patient was able to breathe comfortably (Group I). The site of nasotracheal intubation was decided by 1 rhinologic specialist who evaluated preoperative dental computed tomography (Group II). The site of nasotracheal intubation was decided upon nasal endoscopic findings, dental computed tomography evaluation, and rhinologic pretreatment (Group III).Group II and Group III showed less damage to the nasal mucosa compared with the nasal status of Group I. Upon comparing Group II and Group III, Group III showed better overall status of the nasal mucosa compared with Group II. Visual analogue scale scores for nasal obstruction were pretty similar for all groups on the first postoperative day. In Group III, the nasal mucosa, however, was improved to that of preoperative status on the third postoperative day.In conclusion, it may be useful to pre-evaluate the mucosal and anatomical status of the nasal cavity to select patients requiring rhinologic pretreatment and decide the site for nasotracheal intubation to minimize complications arising from nasotracheal intubation.