The embryonic development of the lateral nasal wall from 8 to 24 weeks

Severe Hypoplasia of Paranasal Sinuses and Turbinates

This case report describes a patient in their 40s with a history of bronchiectasis, azoospermia, and epididymal cysts presented with bilateral nasal obstruction.

Bilateral Concha Bullosa Within Concha Bullosa: Unique Middle Concha Variation

The middle nasal turbinate is an important anatomical formation located on the lateral nasal wall. Concha bullosa can be defined as the presence of an air gap inside the turbinate. It is the most common middle nasal turbinate variation. It is often asymptomatic, but can sometimes cause nasal obstruction. In this study, an asymptomatic patient with concha bullosa within concha bullosa in both middle turbinates, which has not been reported before in the literature, is presented. Laryngoscope, 2024.

Association among Orthodontic Malocclusions, Paranasal Sinuses Anatomic Variations and Adenoid Vegetation in Children Using CBCT

The aim of this study is to evaluate the relationship between orthodontic malocclusion, paranasal sinus (PS) variations, and adenoid vegetation in a group of pediatric patients with chronic rhinosinusitis. Clinical and radiographical data were retrospectively evaluated and 58 patients were diagnosed as having chronic sinus disease. Cone-beam computed tomography (CBCT) images were acquired with Newtom-3G. Anatomical variations of the PS were assessed on every section. Additionally, for cephalometric analysis, the images were imported into the InVivoDental software program. A total of 252 anatomical variations, which encompassed 19 different types, were detected in the current study. Concha bullosa was the most common anatomical variation, at 72.4%. Septum deviation was the second most common one, at 67.2%. The Class III group exhibited a significantly higher prevalence of concha bullosa and secondary middle turbinate than the other groups. While adenoid vegetation was most common in the Class III group, sinusitis and antral disease were most common in the Class II group. Overall, Class III subjects exhibited fewer PS variations. In conclusion, concha bullosa emerged as the most prevalent anatomical variation, with distinctive patterns observed across different malocclusion groups. Therefore, CBCT is useful, especially in pediatric patients, due to its low dose advantage.

Pediatric Paranasal Sinuses- Development, Growth, Pathology & Functional Endoscopic Sinus Surgery

The paranasal sinuses (maxillary, frontal, ethmoid, and sphenoid sinuses) are complex anatomical structures. The development and growth of these have been investigated utilizing a number of different methods ranging from cadaveric analysis to modern cross sectional imaging with 3D modeling. An understanding of normal pediatric paranasal sinus embryology and development enables us to better determine when pathology may be affecting the normal developmental process. Cystic fibrosis, chronic sinusitis, deviated nasal septum and cleft lip and palate are some of the conditions which have been shown to effect paranasal sinus development to varying degrees. Functional endoscopic sinus surgery (FESS) is becoming increasingly common and an understanding of sinus anatomy together with when periods of rapid growth occur during childhood is important clinically. Although concerns have been raised regarding the impact of FESS on facial growth, there is limited evidence of this in regards to either changes in anthropomorphic measurements or clinical assessments of symmetry post operatively.

[Features of the architectonics of the structures of the nasal cavity and choanal zone in children with congenital malformations of the eyes]

The article provides data on the embryogenesis of the eyeball, nasolacrimal canal and nasal cavity. A frequent combination of congenital choanal atresia and anomalies in the development of the eyes was noted, most likely associated with the temporal and topographic parallelism of the intrauterine development of these anatomical areas. In order to assess the condition of the nasal cavity and choanal region in congenital eye pathology, 43 children with ophthalmological malformations were examined. In 32 (74.4%) children, according to endoscopic examination, changes in the anatomy of the choanal region with a change in its size in the form of incomplete atresia were revealed. The results obtained allow the authors to recommend that all children with congenital ophthalmological malformations be examined and monitored by an otolaryngologist with an endoscopic examination of the nasal cavity and nasopharynx.

Using 3D-reconstruction to analyse typical growth trends of the maxillary sinus in children

OBJECTIVES

There remains a lack of consistent evidence surrounding the developmental anatomy of the maxillary sinus (MS), despite its clinical significance in radiological interpretation and surgical intervention. Our aim was to analyse the typical growth trends of the MS throughout development, to better understand its morphological transformation from birth until late adolescence.

METHODS

Computed Tomography (CT) scans of individuals aged 0-18 years within the Auckland District Health Board region in New Zealand were examined retrospectively. Sixty-five patients were selected for the study after careful review of criteria. Manual 3D-reconstruction was utilised to replicate the MS from CT images and the mean changes in size, volume and shape with increasing age were analysed. Principal component analysis (PCA) was performed to statistically calculate the mean 3D shapes of the MS in each age group and analyse the independent modes of variation evident in sinus morphology between individuals of each age category.

RESULTS

At 0-1 years of age, mean MS size was 1.03 × 1.82 × 1.27 cm (width, length, height) with a mean volume of 0.81 cm³. By 16-18 years, mean size increased to 3.39 × 4.30 × 4.63 cm and mean volume became 21.63 cm³. Growth increased linearly but most rapid expansion occurred in the first 4-5 years of life. No significant differences were observed between males and females or right and left sides. Sinus morphology gradually progressed throughout the course of growth from an ellipsoidal structure at its rudimentary phase to a pyramidal shape when fully matured. PCA revealed that within younger age groups significant variation was observed in MS size, while older age groups had relatively less size variation but increased variability in 3D shape.

CONCLUSIONS

The results of this study can be used as a reference for typical MS growth in healthy children and as a basis to study how disease or surgical intervention may influence sinus development in children.

A review of genetics of nasal development and morphological variation

The nose is central in the determination of facial esthetics. The variations in its structural characteristics greatly influence the ultimate dentoskeletal positioning at the end of an orthodontic therapy. A careful insight into its developmental etiology will greatly aid the health care professional in identifying patient's real concern about the facial appearance. This in turn will aid in the fabrication of a better treatment plan regarding the end placement goals for the teeth and jaws in all the three dimensions of space. However, this important structure is often missed as a part of the diagnostic and treatment planning regime owing to the lack of meticulous understanding of its developmental etiology by the orthodontists. The development of the nose in the embryo occurs in pre skeletal and skeletal phases by a well-coordinated and regulated interaction of multiple signaling cascades with the crucial importance of each factor in the entire mechanism. The five key factors, which control frontonasal development are sonic hedgehog (SHH), fibroblast growth factors (FGF), transforming growth factor β (TGFβ), wingless (WNT) proteins, and bone morphogenetic protein (BMP). The recent evidence suggests the association of various nasal dimensions and their related syndromes with multiple genes. The revelation of nasal genetic makeup in totality will aid in ascertaining the direction of growth, which will govern our orthodontic treatment results and will also act as a harbinger for potential genetic editing and tissue engineering. This article describes at length the morphological and genetic aspect of nasal growth and development in light of the gender and racial variability along with the emphasis on the importance of knowing these nasal features with regard to diagnosis and treatment planning in orthodontics.

Novel insights into the development of the avian nasal cavity

In embryonic amniotes, patterning of the oral and nasal cavities requires bilateral fusion between craniofacial prominences, ensuring an intact primary palate and upper jaw. After fusion has taken place, the embryonic nasal cavities open anteriorly through paired external nares positioned directly above the fusion zones and bordered by the medial nasal and lateral nasal prominences. In this study, we show that in the chicken embryo, the external nares initially form as patent openings but only remain so for a short period of time. Soon after the nasal cavities form, the medial nasal and lateral nasal prominences fuse together in stage 29 embryos, entirely closing off the external nares for a substantial portion of embryonic and fetal development. The epithelium between the fused prominences is then retained and eventually develops into a nasal plug that obstructs the nasal vestibule through the majority of the fetal period. At stage 40, the nasal plug begins to break down through a combination of cellular remodeling, apoptosis, as well as non-apoptotic necrosis, leading to completely patent nasal cavities at hatching. These findings place chickens in a category with several species of nonavian reptiles and mammals (including humans) that have been found to develop a transient embryonic nasal plug. Our findings are discussed in the context of previously reported cases of nasal plugs as part of normal embryonic development and provide novel insight into the craniofacial development of a key model organism in developmental biology.

Analysis of the development of human foetal nasal turbinates using CBCT imaging

PURPOSE

The morphological structure of the nasal cavity (NC) is important for endoscopic surgical treatment. The location of nasal turbinates, including the superior turbinate (ST), middle turbinate (MT) and inferior turbinate (IT), are well presented during the formation of the human NC in cone beam CT (CBCT) images. There is a complex relationship between the nasal sinuses, the maxillary sinus (MS), ethmoidal sinus and sphenoid sinus, during formation of the NC structure at the morphological level. There is a need to clearly define the relationships of these nasal elements at the ossification level, during development.

METHODS

We investigated the three-dimensional construction of human foetal NC elements, including ST, MT, IT and vomer, using CBCT images from 16 weeks gestation (E16) to E31 (25 foetuses) and compared it to histochemical observations (E25).

RESULTS

At the stage of ossification, the studied elements are elongated in the posterior region near the sphenoidal bone, showing that the locations of the ST, MT, and IT are important during formation of the NC. CBCT analysis revealed that the horizontal and vertical directions of nasal turbinates affect the formation of the human NC.

CONCLUSION

The location and elongated development of the MT is one of the most important elements for NC formation. The relationship between the nasal sinus and nasal turbine at the level of ossification may provide useful information in clinical treatment of children.

Integration of the nasal complex: Implications for developmental and evolutionary change in modern humans

OBJECTIVES

Assessing the strength of integration among different regions of the modern human nasal complex is important for developing a more thorough understanding of the determinants of nasal morphology. Given the morphogenetic influence of cartilage on adjacent intramembranous growth sites, the interaction between chondrocranial- versus intramembranous-derived nasal structures may have a significant influence on patterns of nasal variation. The purpose of this study is to examine integration between the chondrocranial- and intramembranous-derived regions of the nasal complex.

MATERIALS AND METHODS

Using computed tomograph (CT) scans, we collected three-dimensional coordinate landmark data from a static adult sample (n = 62). First, using centroid size, and the symmetric and asymmetric components of shape variation, we examined the strength of integration between landmarks representing chondrocranial-derived structures (e.g., ethmoid, external nasal cartilages) and landmarks representing intramembranous-derived structures (nasal floor, anterior nasal aperture, etc.). Second, given that the strength of integration is a relative measure, we compared integration between chondrocranial- and intramembranous-derived structures to the more modularized external and internal regions of the nasal complex.

RESULTS

There was significant moderate morphological integration between chondrocranial- versus intramembranous-derived regions of the nasal complex. Moreover, integration between chondrocranial- versus intramembranous-derived structures was consistently stronger when compared to external versus internal regions for both the symmetric and asymmetric components of variation. Thus, more covariation within the nasal complex could be explained by the relationship between chondrocranial- and intramembranous-derived structures.

CONCLUSIONS

Our results suggest that the interaction between chondrocranial- and intramembranous-derived structures may be an important determinant in the patterning of nasal complex variation.

Rare anatomic variation: true bifid inferior turbinate

Nasal anatomic variations are relevant during nasal surgical and endoscopic procedures. The extent of imaging methods, such as the cone beam computed tomography (CBCT), allows a better characterization of such peculiar anatomic traits. The bifid inferior turbinate (BIT) is a rare finding, being previously reported less than ten times. It was found and described on CT scans of patients, being usually associated with the absence of the uncinate process (UP). We hereby report for the first time a bilateral true BIT which differs from the previously reported BITs by the fact that the UPs were present and the bifidity was oriented laterally. In the light of this new find, we consider that the variant resulted from UP displacement should be regarded as a false bifid, or double, inferior turbinate. Bifidity of the inferior turbinate was not previously evaluated in CBCT, as well as in three-dimensional volume renderizations. So, CBCT proves as an efficient tool to investigate prevalence of rare anatomical variants. Noteworthy, CT studies of patients on a case-by-case basis allows a better performance of surgical and endoscopic procedures.

Development of the nasolacrimal apparatus in the Mongolian gerbil (Meriones unguiculatus), with notes on network topology and function

The nasolacrimal apparatus (NLA) is a multicomponent functional system comprised of multiple orbital glands (up to four larger multicellular exocrine structures), a nasal chemosensory structure (vomeronasal organ: VNO), and a connecting duct (nasolacrimal duct: NLD). Although this system has been described in all tetrapod vertebrate lineages, albeit not always with all three main components present, considerably less is known about its ontogeny. The Mongolian gerbil (Meriones unguiculatus) is a common lab rodent in which the individual components of the adult NLA have been well studied, but as yet nothing is known about the ontogeny of the NLA. In this study, serial sections of 15 fetal and three adult Mongolian gerbil heads show that the development of the NLA falls into three fetal stages: inception (origin of all features), elongation (lengthening of all features), and expansion (widening of all features). No postnatal or juvenile specimens were observed in this study, but considerable growth evidently occurs before the final adult condition is reached. The development of the orbital glands and the VNO in the Mongolian gerbil is largely consistent with those in other mammals, despite a slight nomenclatural conundrum for the anterior orbital glands. However, the Mongolian gerbil NLD follows a more circuitous route than in other tetrapods, due mainly to the convoluted arrangement of the narial cartilages, the development of a pair of enlarged incisors as well as an enlarged infraorbital foramen. The impact of these associated features on the ontogeny and phylogeny of the NLA could be examined through the approach of network science. This approach allows for the incorporation of adaptations to specific lifestyles as potential explanations for the variation observed in the NLA across different tetrapod clades.

Augmented BMP signaling in the neural crest inhibits nasal cartilage morphogenesis by inducing p53-mediated apoptosis

Bone morphogenetic protein (BMP) signaling plays many roles in skull morphogenesis. We have previously reported that enhanced BMP signaling through the BMP type IA receptor (BMPR1A) in cranial neural crest cells causes craniosynostosis during postnatal development. Additionally, we observed that 55% of Bmpr1a mutant mice show neonatal lethality characterized by a distended gastrointestinal tract. Here, we show that severely affected mutants exhibit defective nasal cartilage, failure of fusion between the nasal septum and the secondary palate, and higher levels of phosphorylated SMAD1 and SMAD5 in the nasal tissue. TUNEL demonstrated an increase in apoptosis in both condensing mesenchymal tissues and cartilage of the nasal region in mutants. The levels of p53 (TRP53) tumor suppressor protein were also increased in the same tissue. Injection of pifithrin-α, a chemical inhibitor of p53, into pregnant mice prevented neonatal lethality while concomitantly reducing apoptosis in nasal cartilage primordia, suggesting that enhanced BMP signaling induces p53-mediated apoptosis in the nasal cartilage. The expression of Bax and caspase 3, downstream targets of p53, was increased in the mutants; however, the p53 expression level was unchanged. It has been reported that MDM2 interacts with p53 to promote degradation. We found that the amount of MDM2-p53 complex was decreased in all mutants, and the most severely affected mutants had the largest decrease. Our previous finding that the BMP signaling component SMAD1 prevents MDM2-mediated p53 degradation coupled with our new data indicate that augmented BMP signaling induces p53-mediated apoptosis by prevention of p53 degradation in developing nasal cartilage. Thus, an appropriate level of BMP signaling is required for proper craniofacial morphogenesis.

The nasal cavity of the sheep and its olfactory sensory epithelium

Macro and microdissection methods, conventional histology and immunohistochemical procedures were used to investigate the nasal cavity and turbinate complex in fetal and adult sheep, with special attention to the ethmoturbinates, the vestibular mucosa, and the septal mucosa posterior to the vomeronasal organ. The ectoturbinates, which are variable in number and size, emerge and develop later than the endoturbinates. The olfactory sensory epithelium is composed of basal cells, neurons, and sustentacular cells organized in strata, but numerous different types are distinguishable on the basis of their thickness and other properties; all variants are present on the more developed turbinates, endoturbinates II and III. Mature neurons and olfactory nerve bundles express olfactory marker protein. We found no structure with the characteristics that in mouse define the septal organ or the ganglion of Grüneberg. Our results thus suggest that in sheep olfactory sensory neurons are exclusively concentrated in the main olfactory epithelium and (to a lesser extent) in the vomeronasal organ.

Illustrated review of the embryology and development of the facial region, part 1: Early face and lateral nasal cavities

The early embryological development of the face has been reviewed. One repeating theme to note is the serial closing and then the re-opening of a space. This is seen in the separation of the nasal and oral cavities, the nostrils, and in part 2 the developing eyelids fusing and then re-opening. Part 2 will discuss the further facial development as well as the changes in facial bone appearance after birth.

Functional anatomy of the uncinate process and its role in endoscopic sinus surgery

BACKGROUND

A basic step of Functional Endoscopic sinus surgery-the most modern and revolutionary surgical treatment for chronic and recurring sinusitis, is removal of uncinate process to expose the infundibulum. The purpose of this study is to explore the functional role of uncinate process with special reference to endoscopic sinus surgery.

METHODS

A fixed dose of sterile methylene blue was sprayed into the nasal cavities of post endoscopic sinus surgery cases, 20 without uncinate process preservation and 20 with uncinate process preservation. The area of staining/deposition of the stain in the ethmoidal cavity and the maxillary sinuses was endoscopically observed.

RESULTS

Deposition of methylene blue was consistently found to be occurring in a larger area of the ethmoidal cavity including the maxillary sinus in post endoscopic sinus surgery cases without uncinate process preservation.

CONCLUSION

Uncinate proces probably acts as a protective wall by directing the allergen bearing and contuminated inspired air away from the sinuses and facilitating ventilation of the sinuses in the mucocilliary pretreated expiratory phase. Injudictious removal of the uncinate process especially in cases with allergic rhinosinusitis should thus expose the sinus mucosa to contaminated air.

The relationship between pneumatized middle turbinate and the anterior ethmoid roof dimensions: a radiologic study

The development of pneumatized middle turbinate may affect anterior ethmoid roof formation. The aim of this study was to investigate the relationship between the pneumatized middle turbinate and the dimensions of the anterior skull base structures using computed tomography scans. The coronal reconstructed images of the computed tomography scans were evaluated retrospectively. The lateral and medial ethmoid roof points, the width of the cribriform plate (CP), and the anterior ethmoid roof were identified at the first coronal cut, which was determined by the infraorbital nerve. The pneumatized middle turbinates were measured on the axial, vertical, and sagittal planes. The images of 101 patients were evaluated. The mean axial diameters of the pneumatized middle turbinate on the right and left sides were between 6.93 and 4.95 mm, respectively. The correlation between the axial diameters of the pneumatized middle turbinate and the width of the anterior ethmoid roof (termed AER width) was significant for both sides and gender (p < 0.05). There was a higher correlation on the right side where the pneumatized middle turbinate was observed more frequently (r = 0.357). The relationship between CP width and the diameters of the pneumatized middle turbinate was not significant (p > 0.05) for both sides. Iatrogenic lesions of the skull base occur predominantly in the lateral lamella of the CP. The risk of this complication may decrease with increasing of the AER width. Pneumatized middle turbinate may cause an increase in the width of the anterior ethmoid roof and provide more reliable endoscopic intervention of the anterior skull base and frontal sinus.

Evaluation of inferior turbinate hypertrophy in patients with congenital and traumatic nasal septum deviation

Objective:

To compare mucosal and bony measurements in patients with congenital and traumatic nasal septum deviation and compensatory inferior turbinate hypertrophy.

Methods:

The study examined 50 patients with nasal septum deviation (25 congenital and 25 traumatic) and compensatory inferior turbinate hypertrophy in the contralateral nasal cavity, confirmed by computed tomography.

Results:

The study compared inferior turbinate measurements on the concave and convex sides of the septum, in the congenital and traumatic groups. Measurements comprised: the shortest distance from the median line to the medial border of the conchal bone; the distances from the most medial part of the conchal mucosa and the conchal bone to the lateral line; the projection angle of the inferior turbinate; and the widest parts of the whole inferior turbinate and the inferior turbinate conchal bone. The differences between the concave and convex side measurements were compared in the congenital group versus the traumatic group; for three measurements, the difference between these two groups was statistically significant (p < 0.05).

Conclusion:

The present study findings suggest that the conchal bone has a marked influence on nasal patency in patients with congenital septal deviation. These findings supported the decision to excise the inferior turbinate bone at the time of septoplasty, especially when treating congenital septal deviation.

Paradoxical giant inferior concha

Anatomic variations of the middle and superior conchae are common, but inferior concha anomalies are rare. These anomalies have included pneumatization, agenesis, and duplication. We describe what we believe is the first reported case of a paradoxical curvature of the bony part of the inferior concha. The patient was a 13-year-old girl. The development of a huge inferior concha blocked the left nasal cavity and deviated the nasal septum to the contralateral side, resulting in bilateral obstruction. The patient was successfully treated with surgery.

The drainage system of the paranasal sinuses: a review with possible implications for balloon catheter dilation

BACKGROUND

Intersinus connections and accessory ostia of the maxillary sinus are well known to rhinologic surgeons but are less known for the remaining paranasal sinuses. Probing and dilatation of the natural ostia of diseased sinuses is being popularized currently by the clinical value of balloon catheter dilation (BCD). Although short-term high success rates with treatment of the dilated ostia/duct have been reported with this technique, the potential impact of fractures of adjacent bony septae on accessory sinus ostia, on mucosally lined surfaces, and on intersinus drainage pathways still has not been considered. The aim of this study was to review the literature on accessory sinus ostia, intersinus connections, and mucociliary drainage pathways for the entire sinus system that are relevant to BCD.

METHODS

A literature review was performed.

RESULTS

Accessory sinus ostia exist for each paranasal sinus. Many sinuses drain not only directly into the nasal cavity but also indirectly through adjacent sinuses. Of note, one major drainage pathway of the frontal sinus is over the ethmoid sinuses and via the ethmoids into the maxillary sinus and subsequently into the nose. Drainage of the sphenoid sinus exists both through posterior ethmoidal cells and directly into the nasopharynx.

CONCLUSION

Accessory ostia are not only common for the maxillary sinus but also for the entire paranasal sinus system. BCD may potentially inadvertently impair mucociliary clearance of the sinuses through effects on secondary drainage pathways.

Revisiting human nose anatomy: phylogenic and ontogenic perspectives

This review suggests revisiting nose anatomy by considering the ethmoidal labyrinths as part of the olfactory nose and not as paranasal sinuses. Phylogenetically, the olfactory and respiratory organs of the most primitive vertebrates are separated. Exaptation, a mechanism of evolution, may explain the fusion of the olfactory and respiratory organs in dipnoi. The respiratory and olfactory noses remain anatomically separated by the transverse lamina in most mammals, whose olfactory labyrinth is a blind recess housing the ethmoturbinates. In humans, the partitioning between the olfactory cleft and the ethmoid labyrinth seems to be a consequence of ethmoid bone remodeling induced by the acquisition of an upright posture. The ethmoid bone is derived from the cartilaginous nasal capsule of primitive vertebrates and considered to be a highly conserved region among the bony elements of the skull base. It appears to be involved only in housing and protecting the olfactory function. During the early stages of human fetal development, rupture of the oronasal membrane leads to the integration of the primary olfactory sac in the future respiratory organ. The cartilaginous nasal capsule appears in the tissue under the brain and around the olfactory channels. Its early fetal development is classically regarded as the beginning of paranasal sinus formation. From phylogenic and ontogenic perspectives, it may be regarded as the development of the olfactory labyrinth as modified by the remodeling process of the human face and skull base. The endochondral bony origin of the ethmoid labyrinths makes them substantially different from the other paranasal sinuses.

Morphometric analyses of the development of nasal cavity in human fetuses: an anatomical and radiological study

OBJECTIVE

It was aimed to research the morphometric development of the nasal cavity with dissection and radiological scanning methods and to detect anatomical variations.

DESIGN

Retrospective study.

SETTING

Departments of Anatomy and Radiology, Meram Medical Faculty, Selcuk University.

PATIENTS

Dissection stage was performed on 80 spontaneously aborted fetuses (40 males and 40 females) (63 second trimesters and 17 third trimesters) between 13 and 40 weeks of gestation. Radiological scanning stage was carried out on 40 spontaneously aborted fetuses (19 males and 21 females) (12 second trimesters and 28 third trimesters) with multi-detector computed tomography.

METHODOLOGY

One hundred and sixty nasal cavities and related structures were examined by means of bilateral dissection. Reference images were obtained in the axial plane with 3-mm collimation using multi-detector computed tomography (MDCT; Sensation 64, Siemens, Erlangen, Germany). These reference images were sent to the workstation (Leonardo, Siemens, Germany) and three-dimensional (axial, sagittal, and coronal) reformatted images with 1mm thickness were obtained via multiplanar imaging method.

RESULTS

In the dissected fetuses 16 suprema nasal conchae were determined. Six (15%) NSDs (four towards the left and two towards the right) were detected on radiological sections. The angle between the virtual line from sphenoidal sinus ostium through limen nasi and the horizontal plane was 32.72+/-3.3 degrees on average.

CONCLUSION

It was thought that some anatomic variations (e.g. suprema nasal concha, nasal septum deviation) occur in the fetal period; however, other certain differences (e.g. Onodi, Haller, and Agger nasi cells, concha bullosa) might be with effects of environmental factors (trauma and chronic infections) in postnatal period.

Understanding the formation of maxillary sinus in Japanese human foetuses using cone beam CT

The formation of the maxillary sinus (MS) is tied to the maturation of the craniofacial bones during development. The MS and surrounding bone matrices in Japanese foetal specimens were inspected using cone beam computed tomography relative to the nasal cavity (NC) and the surrounding bones, including the palatine bone, maxillary process, inferior nasal concha and lacrimal bone. The human foetuses analysed were 223.2 ± 25.9 mm in crown-rump length (CRL) and ranged in estimated age from 20 to 30 weeks of gestation. The amount of bone in the maxilla surrounding the MS increased gradually between 20 and 30 weeks of gestation. Various calcified structures that formed the bone matrix were found in the cortical bone of the maxilla, and these calcified structures specifically surrounded the deciduous tooth germs. By 30 weeks of gestation, the uncinate process of the ethmoid bone formed a border with the maxilla. The distance from the midline to the maximum lateral surface border of the MS combined with the width from the midline to the maximum lateral surface border of the inferior nasal concha showed a high positive correlation with CRL in Japanese foetuses. There appears to be a complex correlation between the MS and NC formation during development in the Japanese foetus. Examination of the surrounding bone indicated that MS formation influences maturation of the maxilla and the uncinate process of the ethmoid bone during craniofacial bone development.

Nasal, septal, and turbinate anatomy and embryology

This article discusses the development and anatomy of the nasal septum and structures of the lateral nasal wall. Emphasis is placed on anatomic variations associated with surgically correctable nasal obstruction. Common variations, such as deviated nasal septum, inferior turbinate hypertrophy, paradoxic middle turbinate, and concha bullosa, are discussed. Rare developmental causes of nasal obstruction are briefly outlined.

The effect of maxillary sinus surgery on its development

CONCLUSION

The study showed that surgery in the maxillary sinus can affect its development.

OBJECTIVE

To quantitatively evaluate the long-term impact of sinus surgery on its development in the rabbit.

MATERIALS AND METHODS

This was an experimental study performed at an academic tertiary medical center using 20 4-week-old New Zealand white rabbits. The rabbits underwent unilateral right maxillary sinus surgery. The contralateral maxillary sinus used as a control did not undergo the operation. The maxillary sinus ostium was enlarged on the operated side. Volumetric analysis of the maxillary sinus was performed 1 year post-surgery. The maxillary sinus volumes of both sides were calculated using Multidedector CT and the volumetric measurements of the operated side were compared with the non-operated side.

RESULTS

Maxillary sinus development was significantly reduced on the surgical side. Maxillary sinus growth on the surgical side was determined as 87% compared with the non-surgical side.

Imaging of craniofacial and sinonasal anomalies

Whereas CT imaging techniques such as multiple detector spiral imaging with multi-planar reconstructions are desirable in the evaluation of congenital and developmental anomalies of the midface and skull base, there is an essential role for MRI whenever there are related intracranial anomalies. This presentation will focus on describing and classifying the known craniofacial anomalies that have common manifestations in the sinonasal regions, the orbits, and the skull base. Diagrams and clinical cases are utilized to demonstrate the key embryological events leading to the common dysplasias of the craniofacial and sinonasal regions.

Early development of the nose in human embryos: a stereomicroscopic and histologic analysis

OBJECTIVES/HYPOTHESIS

To analyze the morphologic features of the nose in the human embryo from the 4th to 8th developmental week according to Carnegie stage.

STUDY DESIGN

Stereomicroscopic and histologic analysis of the morphology of the human embryo.

METHODS

A total of 27 cases of embryos, ranging from Carnegie stage 13 to 23, were analyzed. The external morphology was observed with a stereomicroscope, photographed, and analyzed. The histologic features were observed with a light microscope in the horizontally transected specimens stained with hematoxylin-eosin.

RESULTS

The nasal placode was observed in stage 13, and it became flat or even concave in stage 14. In stage 15, the nasal pit was formed. In stage 16, the nasal sac and nasal fin were observed. In stage 17, the oronasal membrane was formed by thinning of the nasal fin. In stage 18, the primitive choana was established by a rupture of the oronasal membrane. In stage 19, the lateral palatine process projected vertically below the level of the tongue. The cartilaginous nasal capsule was formed in stage 20. In stage 21, the olfactory area was localized to the upper portion of the lateral nasal wall and the nasal septum. In stage 22, the lateral palatine process developed in a somewhat horizontal orientation. In stage 23, the premaxilla and primitive choana were formed.

CONCLUSIONS

The development of the nose is most active from Carnegie stage 13 to 19, which corresponds to the end of the fourth embryonic week to the end of the seventh week. Thus, this period is considered to be the most important period in human nasal embryonic development.

Long-term outcome of facial growth after functional endoscopic sinus surgery

OBJECTIVE

We sought to determine whether functional endoscopic sinus (FES) surgery performed in children with chronic rhinosinusitis alters facial growth.

STUDY DESIGN AND SETTING

This was a retrospective age-matched cohort outcome study performed at a tertiary care hospital.

RESULTS

Sixty-seven children participated. There were 46 boys and 21 girls, and the mean age was 3.1 years at presentation and 13.2 years at follow-up. There were 46 children who underwent FES surgery and 21 children who did not undergo FES surgery. Quantitative anthropomorphic analysis was performed using 12 standard facial measurements. A facial plastic expert performed qualitative facial analysis. Both quantitative and qualitative analyses showed no statistical significance in facial growth between children who underwent FES surgery and those who did not undergo FES surgery.

CONCLUSIONS

In this study, there was no evidence that FES surgery affected facial growth.

SIGNIFICANCE

These results will aid physicians when discussing with parents the risks of FES surgery.

The forgotten turbinate: the role of the superior turbinate in endoscopic sinus surgery

The fate of the middle turbinate in endoscopic sinus surgery has been a subject of debate for some time. The superior turbinate's role, however, has been largely passed over. Past anatomic descriptions and illustrations have given surgeons the incorrect impression that this structure is well superior and out of the field of dissection. Injury to the superior turbinate may account for postoperative hyposmia. The superior turbinate also serves as a constant landmark for the sphenoethmoidal recess, and a limited resection allows the surgeon to identify and include the natural ostium of the sphenoid sinus in the sphenoidotomy. The embryology and anatomy of the superior turbinate are reviewed. An approach to the natural ostium of the sphenoid sinus from the lateral side of the middle turbinate, using the superior turbinate as a guide, is described.

The embryonic development of the human ethmoid labyrinth from 8-40 weeks

The embryonic development of the human ethmoid labyrinth was studied in 24 fetal heads aged between 8 and 40 weeks of gestation under light microscopy. The uncinate process was identifiable at 8 weeks of gestation on the laterosuperior portion of the inferior turbinate; however, at this stage of development, the ethmoid bulla was not apparent. The ethmoid bulla developed on the lateral wall of the middle meatus by 12 weeks of gestation. By 14 weeks, the primordial ethmoid infundibulum and primordial maxillary sinus were seen developing between the uncinate process and the ethmoid bulla. It was obvious that the anterior and middle ethmoid cells developed from the ethmoid bulla. By 22 weeks of gestation, the first cell of the anterior ethmoid group was evident in the anterior-inferior portion of the ethmoid bulla. By 23 weeks of gestation, the first cell of the middle ethmoid group was visible in the superior portion of the ethmoid bulla. Pneumatization of the middle turbinate occurred as part of normal development of the ethmoid labyrinth. By 32 weeks of gestation, the ostium for the development of the middle turbinate cell was seen in the superior-interior portion of the middle turbinate. These observations provide new insight into the development of the ethmoid labyrinth and have important implications for the understanding of normal anatomy and developmental variants of the ethmoid labyrinth.

Morphogenesis of the Lateral Nasal wall from 6 to 36 weeks

This research describes the development of the lateral nasal wall, the description of which will allow a better comprehension of its anatomic complexity. One hundred embryos and fetuses from the sixth to thirty-sixth weeks of morphologic age were studied. The seventh week shows the first buds of the three turbinates. At the ninth week the precartilaginous nucleus of the inferior turbinate is observed. Likewise, at the tenth week the uncinate process appears, and the invagination of the epithelium begins the formation of the infundibulum and the maxillar sinus. At the fourteenth week the cartilaginous nasal capsule is present. The epithelium is invaginated, starting the formation of the ethmoid cells. During the seventeenth week of development the invagination of the mucus has invaded the maxillar bone, which constitutes the maxillar sinus. At the thirty-sixth week the lateral nasal wall is well developed. In 23 fetuses the supreme turbinate (fourth) was found. Although the length of the lower three turbinates increased progressively and proportionally in intrauterine life without differences between the sexes, the fourth remains invariably at an average length of 5 mm from the fourteenth to the thirty-sixth and was present in 65% of male fetuses.