CT evaluation of the bony nasal pyramid dimensions in Anatolian people

[Piriform aperture as a cause of nasal obstruction. Part I. Anthropometric characteristics in different populations (systematic review).]

The piriform aperture (PA) is anatomically an opening in the central part of the facial skull. To date, the piriform aperture, as an element of the static component of the internal nasal valve (INV) and as a possible cause of its dysfunction, has not received proper surgical attention. If PA is considered as a possible cause of nasal obstruction, then the main parameter is its width, which has a direct effect on the volume of the INV area. This parameter is the focus of the presented work. Despite the absence of generally accepted normative indicators for PA, we currently know the shape and size of the piriform aperture in different ethnic groups of the population, described in the article. As a result of the analysis of the presented research results, it was revealed that the width of the PA is influenced by the gender, age and ethnicity of the individual. The anthropometric data of the piriform aperture require further study, since they are of important reference value not only in the theory of medical research, but also in practical otorhinolaryngology, maxillofacial and plastic surgery, pulmonology.

Analysis of Facial Skeletal Morphology: Nasal Bone, Maxilla, and Mandible

The growth and development of facial bones are closely related to each other. The present study investigated the differences in the nasomaxillary and mandibular morphology among different skeletal patterns. Cephalograms of 240 participants were divided into 3 groups based on the skeletal pattern (Class I, Class II, and Class III). The dimensions of nasomaxilla (nasal bone length, nasal ridge length, nasal depth, palatal length, and maxillary height) and mandible (condylar length, ramus length, body length, symphysis length, and entire mandibular length) were measured. One-way analysis of variance and Pearson's correlation test were used for statistical analysis. No significant differences were observed among the skeletal patterns in terms of nasal bone length, palatal length, maxillary height, or condylar length. Class II had a significantly shorter ramus, mandibular body, and entire mandibular length compared with those of Class I and Class III. Nasal ridge length exhibited a significant moderate correlated with nasal bone length (correlation coefficient: 0.433) and maxillary height (correlation coefficient: 0.535). The entire mandibular length exhibited a significant moderate correlated with ramus length (correlation coefficient: 0.485) and body length (correlation coefficient: 0.536). In conclusion, nasal and maxillary dimensions exhibited no significant difference among the 3 skeletal patterns. Mandibular body and entire mandibular lengths were significantly positively correlations with Class III skeletal patterns.

Computed Tomography Evaluation of Nasal Dimensions among Different Singaporean Ethnicities

Osteotomies in rhinoplasty are performed to correct deformities in nasal contour. The size of osteotome used is dictated by the thickness of the bony nasal pyramid along the osteotomy route. The aim of this study is to determine whether nasal bony dimensions differ between different ethnic groups in Singapore. Randomly selected patients' computed tomography (CT) scans of the face performed between the years 2010 to 2013 in our institution (Khoo Teck Puat Hospital) were evaluated. The setting was a tertiary government hospital. CT images of 309 patients (233 Chinese [147 males, 86 females], 32 Malays [16 males, 16 females], and 44 Indians [33 males, 11 females]) were evaluated. Anthropomorphic measurements of the nasal bone along the track of the lateral, medial, and intermediate osteotomies, as well as the nasal bone length and pyriform aperture width were measured on the CT images by two independent observers. Statistical analysis was performed using Student's t-test and two-way analysis of variance (ANOVA) test. There was no significant difference between the nasal pyramid bone thickness between different ethnicities along the osteotomy tracks (p > 0.05; degrees of freedom [df] = 2). However, there was a significant difference between males and females of the same ethnicity at the low level of the lateral osteotomy (p = 0.003) and the midlevel (p = 0.002) and high-level (p = 0.004) of the intermediate osteotomy. There was a statistically significant difference in nasal pyramid length (p < 0.05, df = 2) and pyriform aperture width (p < 0.05, df = 2) among the races and between the genders (p < 0.05). The mean difference in nasal pyramid length of 2.54 mm and pyriform aperture width of 1.89 mm was particularly significant between the Chinese and the Indians. Gender and ethnic differences in nasal bony dimensions should be considered in surgical planning for rhinoplasty.

Nasal Floor Asymmetry Is Associated With Nasal Obstruction

PURPOSE

The role of morphologic characteristics of the nasal cavity in nasal obstruction is not yet sufficiently understood. The aim of this study was to determine which morphometric parameters of the nasal cavity severely impair nasal breathing and when.

PATIENTS AND METHODS

In a hospital-based, computed tomography-morphometric cross-sectional study, we evaluated computed tomography coronal scans of patients with known nasal obstruction scheduled to undergo functional nasal surgical procedures (cases) and trauma patients without facial involvement or known nasal obstruction (controls). The primary predictor variable was case versus control. In both groups, we measured and compared the piriform aperture width; nasal floor canting; piriform aperture vertical height, height-width ratio, and total cross-sectional area; height difference between the right and left nasal floors; and nasal septal thickness; as well as age and gender differences. Metric data means, standard deviations, and 95% confidence intervals were calculated and analyzed.

RESULTS

The sample was composed of 60 patients evenly divided between cases and controls. Of these, 30 were men. The average age of the cases and controls was 27.4 ± 7.8 years and 38.5 ± 18.6 years, respectively (P < .001). The differences in piriform aperture width were not statistically significant between cases and controls (23.3 ± 1.9 mm and 23.8 ± 1.7 mm, respectively; P > .2). In contrast, we noted statistically significant differences between cases and controls in nasal floor canting (5.4° ± 4.6° and 1.8° ± 1.5°, respectively; P < .001) and height difference between the right and left nasal floors (1.8 ± 1.2 mm and 1.0 ± 0.7 mm, respectively; P = .002).

CONCLUSIONS

Nasal floor canting of 3° or greater and a height difference between the right and left nasal floors of 1.5 mm or greater may contribute to the etiology of clinically relevant nasal obstruction. A piriform aperture width of 22 mm or less may be considered narrow. Future studies can determine when and how exactly to surgically address a clinically relevant narrow piriform aperture and nasal floor canting.

An Analysis of Association Between Nasal Bone Morphology and Sinonasal Anatomical Variations

The goal of this study was to investigate the association between various sinonasal anatomical variations and the morphological features of lateral nasal bone, using paranasal computerized tomography (PNCT) sections. Two hundred and fifty patients who underwent a PNCT scan because of a prediagnosis of nasal septum deviation or sinusitis were included in the study. For each patient, presence of the following anatomical variations was determined on CT sections: length and thickness of nasal bone, thickness of intermediate nasal bone, pneumatized middle turbinate, paradox middle turbinate, Agger nasi cell, Haller cell, Onodi cell, supraorbital cell, pneumatized uncinate process, and nasal septal deviation. The effect of each anatomical variation on the length and thickness of the lateral nasal bone was investigated. The patients with bilateral pneumatized middle turbinate and the patients with bilateral Agger nasi cell had a thinner lateral nasal bone both on the right and the left sides compared to those without. The patients with bilateral Onodi cell and Agger nasi cell had a longer lateral nasal bone both on the right and the left sides compared to those without. The nasal bone thickness was significantly thicker on the deviation side than the contralateral nasal bone. The nasal bone length was significantly longer on the side of the septum deviation. In this study, we found that sex, presence of Agger nasi and Onodi cells, pneumatization of middle turbinate, and direction of nasal septal deviation influenced the morphology of the nasal bone. For successful nasal surgery, careful examination of preoperative anatomical variations is very important.

Nasomaxillary and mandibular bone growth in primary school girls aged 7 to 12 years

Background/purpose

Facial bone growth manifests in primary school-aged children, especially girls. This study investigated the changes in nasomaxillary and mandibular morphology of primary school girls.

Materials and methods

Cephalograms of 60 primary school girls were divided into 3 groups (group I, aged 7–8 years; group II, aged 9–10 years; and group III, aged 11–12 years). The dimensions of the nasomaxilla (nasal bone length, nasal ridge length, nasal depth, palatal length, and maxillary height) and mandible (condylar length, condylar width, coronoid length, coronoid width, ramus length, body length, symphysis length, and entire mandibular length) were measured. One-way ANOVA and Pearson's correlation coefficient were used for statistical analysis.

Results

Nasal ridge length, nasal depth, and maxillary height were significantly greater in group III than in group I and group II. Condylar width and body length were significantly greater in group III than in group I and group II. Pearson's correlation revealed significant positive correlations between age and nasal ridge length, nasal depth, or maxillary height. There were also significant positive correlations between age and ramus length, body length, or entire length of the mandible.

Conclusion

We found that nasal ridge length, nasal depth, maxillary height, condylar width and body length were significantly greater in group III than in group I or in group II. Moreover, there were significant correlations between age and the nasal ridge length, nasal depth, maxillary height, ramus length, body length, or entire length of the mandible.

TMJ arthrosis: does the occlusal relationship really interfere? A comparison between cone beam computed tomography and dried skulls

The aim of this study was to investigate the association between condylar bone morphological characteristics with occlusal conditions. Besides the study will compare the tomography images with the real condition in 122 temporomandibular joints from 61 skulls. The occlusal conditions were evaluated by number of teeth missing, measurement of overjet and overbite, in millimeters, and presence or absence of crossbite, openbite and dental rotation. The condylar bone morphological conditions were classified in five types (normal, presence of erosion, presence of osteophytes, flattening and/or deformation). This classification was used in real skulls and in Cone Beam Computed tomography (CBCT) images. The data were submitted to statistical analysis with a level of significance of 0.05. Occlusal variables have no association to morphologic data (p > 0.05). Normal condylar bone was seen in 62 CBCT versus 53 in real skulls while morphological alterations were seen in 60 CBCT versus 67-real condyles. The clinical and tomographic measurements were compared, demonstrating an important difference in the classification demonstrating poor association between detection methods (k - 0.3, p < 0.001). The occlusal conditions appear to have no correlation with the morphological condyle conditions. The CBCT is a reliable diagnostic method, although it may present divergences of findings when compared with clinical raw examination to morphologic condylar conditions.

Computed Tomography Evaluation of Nasal Bone and Nasal Pyramid in the Turkish Population

OBJECTIVE

To classify shapes of the nasal bones in the Turkish population and comparatively evaluate the sizes of nasal bone and piriform apertures.

METHODS

Two- and three-dimensional paranasal sinus computed tomography images of 363 patients were evaluated. Upper, intermediate, and inferior thickness of bilateral nasal bones and thickness of medial and lateral osteotomy line were measured. The shapes of the nasal bones were classified.

RESULTS

The mean thickness of nasal bone in the study participants was 1.99 ± 0.40 mm, the mean thickness at the level of medial osteotomy line was 1.99 ± 0.40 mm, the mean thickness at the level of lateral osteotomy line was 1.75 ± 0.30 mm, the mean length of nasal bone was 1.75 ± 0.30 mm, maximum width and height of piriform aperture were 23.41 ± 2.68 and 36.76 ± 7.06 mm, respectively. When the patients were classified according to the type of nasal bone, 26.7% had type A, 10.5% had type B, 19.6% had type D, and 15.4% had type E nasal bone.

CONCLUSION

The results of the current study provide information about morphological characteristics of nasal bone and piriform aperture in the Turkish population and would therefore reduce postoperative complications after reconstructive surgery and contribute otolaryngology and anthropology.

Relationship between the degree and direction of nasal septum deviation and nasal bone morphology

BACKGROUND

Nasal septal deviation may affect nasal bone growth and facial morphology. Knowledge of nasal morphologic parameters may plays an important role in planning successful rhinoplasty and septoplasty operation. The aim of our study was to evaluate the relationship between the direction and degree of nasal septal deviation with nasal bone morphology, along with factors such as age and gender.

METHODS

Maxillofacial computed tomography (CT) of 250 patients with nasal septal deviation was analyzed retrospectively in this study. We excluded patients with factors that could affect their nasal bone morphology, and a total of 203 patients (111 males, 92 females; mean age, 36.23 years; age range, 18-79 years) were evaluated. The nasal deviation angle was measured on coronal CT images as the angle between the most deviated point of the septum, and the midline nasal morphology was determined by measuring nasal length, internasal angle and lateral and intermediate nasal thickness on both sides.

RESULTS

The deviation of nasal septum has been detected as to the right in 107 patients (52.7%) and to the left in 96 patients (47.3%). Lateral and intermediate nasal bone thickness and nasal bone length were significantly greater on the ipsilateral deviation side (Table 3). No significant correlation was found between the variation of the nasal deviation angle and nasal bone morphology (Table 4). There were significant differences between the sexes for all investigated parameters except for the nasal deviation angle (p = 0.660). We found that the only internasal angle increases with aging (p = 0.002).

CONCLUSION

The study shows that the direction of nasal septal deviation may be a factor that affects nasal bone morphology.

Pyriform aperture enlargement in all aspects

BACKGROUND

The pyriform aperture comprises the central area of facial bone structure. It is formed by the free corners of the nasal bone and the frontal processes of the maxillae, which articulate with each other at the nasomaxillary suture lines. Congenital nasal pyriform aperture stenosis might be linked to various craniofacial problems. This review presents all aspects of pyriform aperture stenosis and enlargement.

METHODS

A literature search was conducted. Pyriform aperture definition, nasal development, congenital nasal pyriform aperture stenosis and pyriform aperture enlargement were reviewed.

RESULTS

One of the most common abnormalities is holoprosencephaly, which is a midline developmental deficiency that may also be present in combination with facial clefting. The aetiology of nasal pyriform aperture stenosis remains unclear. When diagnosed, the choice of treatment is between non-surgical and operative methods, depending on the seriousness of the problem. Provided the sufferer can maintain a secure air passage with the help of specialised medical procedures and respiratory tract adjuvants, operative therapy may be delayed.

CONCLUSION

The operative outcomes are extremely good, and the prognosis relies mainly on coexisting neural and endocrine problems. This paper evaluates the nasal pyriform aperture in detail.

Morphometric Study of Nasal Bone and Piriform Aperture in Human Dry Skull of Indian Origin

INTRODUCTION

Nasal bone and piriform aperture shows racial and geographical differences because of variable climate. The aim of this study was to evaluate the dimensions (maximal width and length), the size and the shape of the piriform aperture (PA) and their sexual dimorphism in North Indian adult.

MATERIALS AND METHODS

In this observational study, dimension of piriform aperture and nasal bone were measured using digital vernier caliper after assessing landmarks around the piriform aperture on the norma frontalis in Frankfurt plane in 40 skull of Indian orgin.

RESULTS

The mean width of the piriform aperture was 24.9±1.59 mm in males and 22.77±1.57 mm in females, the mean length was 29.57±3.28mm in females and 31.16±3.58mm in males. The difference between males and females was significant, and our data correlates well with the previously data acquired from humans skulls. Most of North Indian skulls have platyrhine type of piriform aperture (triangular to oval shape with pyriform aperture index of 0.79). Mean length and width of nasal bone were 17.58±2.47mm and 12.1±0.97mm respectively without sexual.

CONCLUSION

Shape and size analysis of the piriform aperture and nasal bone showed the existence of a significant sexual dimorphism. These results encourage us to go further with functional and imaging correlations. This study will also be helpful in forensic research and anthropology.

The evaluation of morphometry of nasal bone and pyriform aperture using multidetector computed tomography

INTRODUCTION

The aim of this study was to measure nasal bone (NB) and pyriform aperture (PA), morphometrically. Besides, the different types of NB and PA were classified and determined the sexual differences.

MATERIALS AND METHODS

Our study was performed on 120 (60 women, 60 men) multidetector computed tomography images obtained from patients who underwent radiologic examination in the Department of Radiology of Meram Faculty of Medicine, Necmettin Erbakan University. The right, left, and median heights of NB; the superior and inferior widths of NB; the width of PA; and the distance between rhinion and anterior nasal spine (as the height of PA) were measured. Frontonasal and internasal angles were also determined. All data were analyzed statistically using Student's t-test.

RESULTS

The other data of men were higher than of women except for the superior and inferior widths of NB and the frontonasal angle. We also determined the ratio of the height of PA to the height of NB on median plane and the ratio of the height of PA to the width of PA. They were found less than 2.0 in 64.2% and 100% of the cases, respectively. The NB and PA were classified into 8 and 7 different types, respectively.

CONCLUSIONS

The knowledge of the morphometric data and different types of the NB and PA is essential for sex determination, all surgical procedures related to this area, and nasal reconstructions.

CBCT Evaluation of Bony Nasal Pyramid Dimensions in Iranian Population: A Comparative Study with Ethnic Groups

Background. The aim of the present study was to have normative data of nasal bone thickness for use before reconstructive surgery and nasal augmentation through radiography analysis. Methods and Materials. In this descriptive-analytical study, 74 patients were selected from people referred to Radiology Department of Isfahan University for CBCT examination in 2012. Patients with a history of nasal surgery or facial trauma and known congenital anomaly were excluded from the study. Height of nasal bone and width of pyriform aperture and nasal bone thickness in lateral and medial osteotomy line were measured. All these measurements were repeated by two radiologists; finally one sample t-test was performed. Results. The mean thickness of nasal bone on the lateral osteotomy line was 1.92 ± 0.29 mm in females and 1.73 ± 0.32 mm in males (P value = 0.39). The mean thickness of medial osteotomy line was 1.63 ± 0.47 mm in females and 1.94 ± 0.19 mm in males (P value = 0.31). The mean length of nasal bone was 23.5 ± 3.34 mm in females and 25.7 ± 2.96 mm in males (P value = 0.11). The mean width of pyriform aperture was 23.77 ± 2.58 mm in females and 25.67 ± 1.79 mm in males (P value = 0.25). Conclusions. The dimensions of nasal pyramid are known to be significant in choosing suitable osteotome size for reducing surgery side effect. Our results can be used for preoperative estimation of nasal bone dimension of people undergoing reconstructive surgery and augmentation.