Digital radiomorphometric analysis of the frontal sinus and assessment of the relation between persistent metopic suture and frontal sinus development

Personal identification using frontal sinus coding methods: The effect of mixed image modality comparisons

Several code-based methods have been created for comparing the frontal sinus in skeletal identification scenarios. However, little is known regarding matched-pair accuracy rates of these methods or how varying image modalities may affect these rates. The goals of this study were to validate the exclusion rates and to establish matched-pair accuracy rates of two well-cited coding methods, Cameriere et al. [23] and Tatlisumak et al. [24]. Additionally, individual variables were assessed for consistency in scoring between image modalities. Using a sample of U.S. African American, Native American, and European American females and males (n = 225), we examined individual variable scoring and string codes between two different image modalities (radiographs and CT-based 3D models). Arcades showed poor scoring consistency between modalities (p < 0.001). Although exclusion rates were similar to those reported in the original studies (93%-96%), matched-pair accuracy rates were low (13%-18%). None of the demographics (collection, sex, age, ancestry, and orientation) had an effect on the odds of a match. Interobserver and intraobserver analyses showed moderate to near-perfect agreement for all variables except supraorbital cells, which had minimal to no agreement. Currently, we do not recommend the application of these frontal sinus coding methods independent of other supporting identification methods given low variable consistency and accuracy rates. Visual identification should still be used to include or exclude an identification when using the frontal sinus.

Variation, sexual dimorphism, and enlargement of the frontal sinus with age in adult South Africans

OBJECTIVES

To document frontal sinus volume (FSV) in a sample of sub-Saharan Africans with a view to evaluating claims that such populations exhibit comparatively small sinuses. This study also addresses questions related to sexual dimorphism, incidence of sinus aplasia, and the possibility that FSV continues to increase through adulthood.

MATERIALS AND METHODS

FSV was measured from CT scans of adult crania from the Dart Collection. Sex and age were known for each individual. Linear cranial dimensions were used to compute a geometric mean from which a scaled FSV was computed for each cranium.

RESULTS

FSV does not differ significantly between sexes, but females exhibit a higher incidence of aplasia. There is considerable variation in FSV in this sample, with the average ranking among the higher means reported for other population samples. The incidence of FS aplasia falls within the range of values recorded for other population samples. Although our study is cross-sectional rather than longitudinal, there is strong evidence that FSV continues to increase with age throughout adulthood.

DISCUSSION

The FSV mean of our sample contradicts the notion that sub-Saharan Africans possess small sinuses. In a global context, geography (climate and altitude) does not appear to be related to FSV. The absence of sexual dimorphism in our sample is unexpected, as significant dimorphism has been reported for most other population samples. Our results support other indications that the frontal sinus continues to expand throughout adulthood, especially in females, and that it is likely due to bone resorption.

Quantitative anatomy of the primary ossification center of the squamous part of temporal bone in the human fetus

Detailed numerical data about the development of primary ossification centers in human fetuses may influence both better evaluation and early detection of skeletal dysplasias, which are associated with delayed development and mineralization of ossification centers. To the best of our knowledge, this is the first report in the medical literature to morphometrically analyze the primary ossification center of the squamous part of temporal bone in human fetuses based on computed tomography imaging. The present study offers a precise quantitative foundation for ossification of the squamous part of temporal bone that may contribute to enhanced prenatal care and improved outcomes for fetuses with inherited cranial defects and skeletodysplasias. The examinations were carried out on 37 human fetuses of both sexes (16 males and 21 females) aged 18-30 weeks of gestation, which had been preserved in 10% neutral formalin solution. Using CT, digital image analysis software, 3D reconstruction and statistical methods, the size of the primary ossification center of the squamous part of temporal bone was evaluated. With neither sex nor laterality differences, the best-fit growth patterns for the primary ossification center of the squamous part of temporal bone was modelled by the linear function: y = -0.7270 + 0.7682 × age ± 1.256 for its vertical diameter, and the four-degree polynomial functions: y = 5.434 + 0.000019 × (age)4 ± 1.617 for its sagittal diameter, y = -4.086 + 0.00029 × (age)4 ± 2.230 for its projection surface area and y = -25.213 + 0.0004 × (age)4 ± 3.563 for its volume. The CT-based numerical data and growth patterns of the primary ossification center of the squamous part of temporal bone may serve as age-specific normative intervals of relevance for gynecologists, obstetricians, pediatricians and radiologists during screening ultrasound scans of fetuses. Our findings for the growing primary ossification center of the squamous part of temporal bone may be conducive in daily clinical practice, while ultrasonically monitoring normal fetal growth and screening for inherited cranial faults and skeletodysplasias.

Change of frontal sinus in age of according to the international frontal sinus anatomy classification

BACKGROUND

The radiological and surgical anatomy of the frontal sinus should be well-known in all age groups to successfully manage frontal sinus diseases and reduce the risk of complications in sinus surgery.

PURPOSE

To define frontal sinus and frontal cells according to the International Frontal Sinus Anatomy Classification (IFAC) criteria in pediatrics and adults.

MATERIAL AND METHODS

A total of 320 frontal recess regions of 160 individuals (80 pediatric, 80 adults) who underwent a computed tomography (CT) scan of the paranasal sinus (PNS) were included in the study. Agger nasi cells, supra agger cells, supra agger frontal cells, suprabullar cells, suprabullar frontal cells, supraorbital ethmoid cells, and frontal septal cells were evaluated in the CT analysis.

RESULTS

The incidence rates of the investigated cells were determined to be 93.1%, 41.9%, 60.0%, 76.3%, 58.5%, 18.8%, and 0% in the pediatric group, respectively, and 86.3%, 35.0%, 44.4%, 54.4%, 46.9%, 19.4%, and 3.4% in the adult group, respectively. Considering the unilateral and bilateral incidence of the cells, agger nasi cells were highly observed bilaterally in both the pediatric group (89.87%) and the adult group (86.48%).

CONCLUSION

Our study results show that IFAC can be used as a guide to increase the chance of surgical treatment in the pediatric and adult groups and that the prevalence of frontal cells can be determined radiologically and contributes to the generation of estimations of the prevalence of frontal cells.

Does sternal body shape reflect family relationships? A study on a genealogically documented Central European osteological sample (19th-20th centuries)

In forensic contexts, sternal anatomical varieties represent useful tools for the identification of an individual, either by comparison of ante-mortem and post-mortem data, or by potential comparison of data from biologically related individuals. Sternal body variation is also used to detect the biological affinity of individuals in bioarchaeology. However, no study has been made available to date on the degree to which the overall shape of the sternal body reflects the degree of biological relatedness. We, therefore, analyzed the sternal body shape of 10 individuals with known genealogical data, members of one family over three generations including inbred individuals (19th-20th centuries, Bohemia, Czech Republic), and a control sample of 12 biologically unrelated individuals. First, closely biologically related individuals were compared with unrelated individuals based on 10 variables expressing the morphological characteristics of the sternum, and then all individuals were compared based on Fourier analysis depending on their degree of relationship. The results showed that there is a greater degree of shape similarity in biologically related individuals than in unrelated individuals, and variability decreases with an increasing degree of relatedness. Inbred individuals showed the lowest sternum-shape distances and degree of variability, while unrelated individuals, showed the highest distances and variability. Moreover, in some cases, the documented relationships were also supported by a similar morphology of the ossified and fused xiphoid process. Thus, sternal shape analysis expands the possibilities for individual identification and the detection of the biological affinity of individuals for both the forensic sciences and bioarchaeology.

Scaphocephaly and increased intra-cranial pressure in non-operated adults: A controlled anthropological study on 21 skulls

AIM AND SCOPE

The prevalence of increased intra-cranial pressure (ICP) in patients with scaphocephaly is controversial. Here, based on anthropological material, we aimed to determine whether adults with non-operated sagittal synostosis show indirect signs of increased ICP.

MATERIALS AND METHODS

Thirty-eight dry skulls (21 skulls with sagittal craniosynostosis and 17 controls) were selected from the collections of the National Museum of Natural History (Paris, France). All skulls registered as 'fused sagittal suture' or 'scaphocephaly' in the registry of the Museum were included. All had total fusion of the sagittal suture. Controls were selected within skulls of similar origin (France), without visible craniofacial anomalies. The 38 skulls were CT-scanned using a standard medical CT-scan with a protocol dedicated to dry bone imaging. Eight radiological signs associated with raised ICP were assessed: (1) calvaria and (2) skull base thinning, (3) dorsum sellae erosion, (4) sella turcica lengthening, (5) copper beaten skull, (6) suture diastasis, (7) persistent metopic suture, and (8) small frontal sinus. Scaphocephaly was assessed based on head circumference, cranial index, intra-cranial volume, fronto-nasal angle, and inter-zygomatic distance. Linear and non-linear logistic models were used to compare groups.

RESULTS

19/21 skulls with sagittal synostosis were significantly scaphocephalic. None of the criteria for ICP were significantly different in skulls with scaphocephaly relative to controls. Nevertheless, 5 individual skulls with scaphocephaly had ≥ 3 signs in favor of a history of raised ICP. We do not report the significant prevalence of indirect signs of raised ICP in adults with scaphocephaly. These results do not allow ruling out a history of early raised ICP or of minor prolonged raised ICP. Even though our findings support the fact that scaphocephaly is not significantly associated with prolonged raised ICP, individual cases (5/21) with clear signs in favor of a history of brain compression indicate that scaphocephaly correction should be considered as a functional procedure until the production of clear evidence. Cognitive assessments of non-operated adult patients with scaphocephaly could contribute to tackle this recurring question in craniofacial surgery.

Three-Dimensional Evaluation of the Frontal Sinus in Koreans

(1) Background: Among the four paranasal sinuses, the frontal sinus is in the frontal bone. Recent research trends have been focusing on identifying sex based on the frontal sinus. Thus, this study aimed to provide reference data for the frontal sinus in Korean adults by comparing their sizes using a 3D program. Moreover, this study examined the correlation between the size of the frontal sinus and the length of cranial bone. (2) Methods: Cone-beam computed tomography (CBCT) data were obtained from 60 (male 30, female 30) patients in their 20 s who visited the Department of Dankook University Hospital (DKUDH IRB 2020-01-007). The provided patient CBCT data were utilized to reconstruct the patients’ frontal sinuses and cranial bones in 3D using the Mimics (version 22.0, Materialise, Leuven, Belgium) 3D program. All measurements were analyzed using SPSS (ver. 23.0, IBM Corporation, Armonk, NY, USA). (3) Results: By comparing the frontal sinus size of Korean adults according to sex using a 3D program, this study revealed that males had larger frontal sinuses than females. (4) Conclusions: The findings of this study could help in preventing complications that occur in various clinical treatments and analyzing the growth of the frontal sinus in the future.

Cranial morphology in metopism: A comparative geometric morphometric study

BACKGROUND

Cranial sutures are active bone growth sites and any alteration in their normal formation, patency and closure influences the overall cranial morphology. This comparative study aims to establish whether the cranial shape and size are significantly modified when metopic suture persists into adulthood using geometric morphometric analyses.

METHODS

The sample consisted of 63 metopic and 184 non-metopic dry adult male crania. Three-dimensional polygonal models of the crania were generated using a hand-held laser scanner Creaform VIUscan. A total of 50 landmarks were digitized on the three-dimensional models and eight landmark configurations delineating the cranium and its compartments were constructed and analyzed. Geometric morphometric analyses were applied to investigate separately the size and shape differences between the metopic and non-metopic series in each of the landmark configurations.

RESULTS

Significant size differences were established solely in the neurocranium, but not in its total size, rather in its parts. The size modification was expressed by an enlargement of the anterior part of the neurocranium at the expense of the middle and posterior ones. All investigated landmark sets differed significantly between the series regarding the shape. In metopic series, the shape alteration was mainly in a mediolateral widening and an anteroposterior shortening contributing to a more rounded overall shape of the cranium.

CONCLUSIONS

The slight modification of the cranial morphology in metopism suggests that the metopic suture persistence is not an isolated variation limited to the frontal bone. It is rather a complex condition associated with a combination of specific phenotypic characteristics.

The Relation Between the Metopic Suture Persistence and Frontal Sinus Volume and Olfactory Fossa Depth: A Reliability Study with Semiautomatic Volume Measurement

Objective:

This study aims to investigate the relationship of the persistence of metopic suture (PMS), frontal sinus volume (FSV), and olfactory fossa depth (OFD).

Methods:

Tomography scans of 1,603 patients aged 18-65 years were evaluated for the presence of PMS. In the study, 74 PMS cases and 74 controls were included. The appearance of each individual’s frontal sinus was classified as aplasia, hypoplasia, or normal. Two observers independently measured the lateral lamella length (LLL), OFD, and FSV. Interobserver agreement was evaluated with the intraclass correlation coefficient (ICC) and Cohen’s kappa coefficient (κ).

Results:

The prevalence of PMS was found to be 4.99% [95% confidence interval (CI): 4.03-6.17]. The PMS group had five times higher hypoplasia/aplasia than the controls (52.70%, 95% CI: 41.48-63.66 and 10.81%, 95% CI: 5.58-19.91, respectively; p<0.001). An “almost perfect” agreement was detected among observers for the frontal sinus appearance classification: κ=0.807, p<0.001. The ICC of continuous measurements for OFD, LLL, and FSV, respectively, presented “excellent” reliability: 0.956, 0.958, and 0.981, with p<0.001 for each. LLL was shorter, OFD was shallower, and FSV was smaller in the PMS group than the control group (p<0.001). There was a moderate positive correlation between OFD, LLL, and FSV (r=0.306, r=0.302).

Conclusions:

This study interprets that the presence of PMS is related frontal sinus development and volume. With PMS, a smaller FS, shorter lateral lamella, and shallower olfactory fossa may be expected.

Influence of persistent metopic suture on sagittal suture closure

BACKGROUND

Metopic suture lies between the halves of the growing frontal bone and usually closes in early infancy. If the metopic suture fails to close it persists in adulthood and could be considered an anterior continuation of the sagittal suture (SS). This study aimed to investigate if the metopic suture persistence is related to any significant deviations from the normal SS maturation. We also aimed to elaborate linear regression models for age-at-death prediction of the metopic crania and to compare their accuracy with the models developed on the control ones.

METHODS

The SS was investigated in a total of 122 dry adult contemporary male crania of known age-at-death divided in a metopic series (n = 34) and a control one (n = 88). The crania were scanned and high-resolution volumetric images were generated using an industrial μCT system. The SS closure degree was assessed on cross-sectional tomograms using a scale of grades. Both series were compared and linear regression models for age-at-death prediction were elaborated.

RESULTS

The comparison between both series showed that the degree of SS closure differs significantly in all SS sections and bone layers and it is considerably lower in the metopic series. The elaborated linear regression models showed that the error in the age-at-death prediction of the metopic crania is almost two times bigger than that in the control.

CONCLUSIONS

The SS closure in metopic crania is significantly delayed compared to the control, which means that it is entirely unreliable and misleading as an indicator for age-at-death prediction.

Anatomical Variations of the Nasal Cavities and Paranasal Sinuses: A Systematic Review

The anatomy of the nasal cavities and paranasal sinuses is one of the most varied in the human body. The aim of this study is to review the prevalence of anatomical variations in the sinonasal area. This systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. We performed on PubMed a literature search from October 2004 until May 2020. The search strategy included the following keywords: ('paranasal sinus' OR 'frontal sinus' OR 'maxillary sinus' AND ('anatomical variants' OR 'anomalies')). Fifty studies were eligible and included in the analysis. Overall, the studies encompassed a total of 18,118 patients included in this review. Most common anatomical variations include agger nasi cells, nasal septum deviation and concha bullosa. Other variations seen in this region are uncinate process variations, paradoxical middle turbinate, Haller, Onodi and supraorbital ethmoid cells, accessory ostia of maxillary sinus. Less common variations include any sinus aplasia, crista galli pneumatization and dehiscence of the optic or maxillary nerve, internal carotid artery and lamina papyracea. Anatomical variations of this region also differ among ethnic groups. This study highlights the amount, variability and significance of most anatomical variants reported in the literature in the last years. It is essential for the sinus surgeon to have a broad spectrum of knowledge not only of "the typical" anatomy but also all the possible anatomical variations. With modern imaging modalities, anatomical variations can be detected, and uneventful pitfalls might be prevented.

Frontal sinus anatomy of the noble Swéerts-Sporck family and verification of their biological relationships using similarity analysis

The evaluation of frontal sinus similarity is one way to detect biological relationships, especially in small groups, including families of historically known personalities. However, possibilities for studying this issue are currently limited. This contribution deals with the frontal sinuses of a rare osteological sample with known genealogical data, members of the noble Swéerts-Sporck family from the 17th to 20th centuries. The aim is to verify whether the frontal sinuses reflect documented family relationships. Basic dimensions of the frontal sinus such as total surface area and volume, and maximum height and width, and also morphology and anatomical features were evaluated using computed tomography scans. The portions of the frontal sinus above the "external supraorbital line" were analyzed. The degree of similarity between biologically related individuals was determined for each variable and compared with their known biological distance. The degree of similarity based on dimensions was evaluated using both the unadjusted measured data and standardized data adjusted to size. For the unadjusted dimensions, a positive correlation between morphological similarity and biological relatedness was apparent. On the other hand, no positive correlation was apparent for most of the standardized data. Only total volume showed a very weak indication of a positive trend in the standardized data, but this was weaker than in the original values. A positive quantifiable relationship between morphological patterns and biological distance is not clearly indicated. However, nonmetric features do support the documented relationships of the individuals.

Biological relationships and frontal sinus similarity in skeletal remains with known genealogical data

Frontal sinus analysis has potential utility for detecting biologically related individuals. However, the methodological approach to its evaluation, as well as its informative value, have been questioned. The aim of this work is to introduce a new approach to evaluating the frontal sinus using the 'external supraorbital line' (ESOL) and to determine whether there are sex differences within families in frontal sinus measurements and whether frontal sinus similarity reflects known genetic relationships in both measurements and morphology. We examined the skeletal remains of 41 adult individuals (25 males, 16 females), all members of one family over four generations (19th to 20th centuries), including individuals with very close consanguinity. CT images of skulls were acquired, and both the dimensions and morphology of the frontal sinuses were analyzed using their portions above the ESOL. No significant sex differences were found within families based on frontal sinus dimensions. Significant relationships were found between biological distance and the maximum height and morphology of the frontal sinuses. The greatest degree of similarity was found among closely related individuals. Additionally, in several cases, there was a greater degree of similarity between first cousins or grandparents and their grandchildren than among siblings or parents and their children. Total surface, volume and width are not significant indicators of relatedness. Known genetic relationships are also supported by individual morphological features. Variability within families with very close consanguineous relationships was lower than within families with common degrees of consanguinity, although differences are significant only for some variables.

Morphometric study of the primary ossification center of the frontal squama in the human fetus

PURPOSES

Detailed morphometric data on the development of ossification centers in human fetuses is useful in the early detection of skeletal dysplasias associated with a delayed development of ossification centers and their mineralization. Quantitative analysis of primary ossification centers of cranial bones is sporadic due to limited availability of fetal material.

MATERIAL AND METHODS

The size of the primary ossification center of the frontal squama in 37 human (16 males and 21 females) spontaneously aborted human fetuses aged 18-30 weeks was studied by means of CT, digital-image analysis and statistics.

RESULTS

With neither sex nor laterality differences, the best-fit growth dynamics for the primary ossification center of the frontal squama was modelled by the following functions: y = 13.756 + 0.021 × (age)² ± 0.024 for its vertical diameter, y = 0.956 + 0.956 × age ± 0.823 for its transverse diameter, y = 38.285 + 0.889 × (age)² ± 0.034 for its projection surface area, and y = 90.020 + 1.375 × (age)² ± 11.441 for its volume.

CONCLUSIONS

Our findings for the primary ossification center of the frontal squama may be conducive in monitoring normal fetal growth and screening for inherited faults and anomalies of the skull in human fetuses.

Sagittal suture maturation: Morphological reorganization, relation to aging, and reliability as an age-at-death indicator

OBJECTIVES

The sagittal suture (SS) is assumed to be an initial site for the commencement of cranial suture closure as well as the most frequent spot of isolated craniosynostosis. The present study aimed to inspect the reorganization of the SS at the microlevel to assess the relation between its closure and aging and to establish whether it could be used as a reliable indicator in age-at-death prediction.

MATERIALS AND METHODS

The SS was investigated in 68 dry contemporary adult male skulls of known age-at-death. An additional series of 20 skulls was used for verification. The skulls were scanned using a micro-computed tomography system. The SS closure degree was assessed along the three bone layers on cross-sectional tomograms by using a scoring scale.

RESULTS

In the entirely open SS, the bone edges consist of compact bone and are widely separated. With SS maturation, the bone edges come into contact, and the remodeling process leads to a decrease in the sutural area and bone homogenization across all three layers. SS closure is an irregular process roughly related to aging, beginning in the early 20s, reaching its peak at about 30 years of age and abating in the late 40s.

DISCUSSION

Although related to aging, SS closure is not a simple function of it. Rather, the underlying factors inducing and managing this process are multifaceted and complex. Although the etiology of SS maturation remains unclear, it is reasonable to use SS closure cautiously and only as a supportive method for age prediction.

Risk of frontal sinus anterior table fractures after craniofacial trauma and the role of anatomic variations in frontal sinus size: A retrospective case-control study

INTRODUCTION

Purpose of this study was to evaluate a probable risk of frontal sinus size for traumatic depressed anterior table fractures in patients with similar forehead trauma.

METHODS

We conducted a retrospective case-control study with a case group of consecutive treated patients with displaced frontal sinus anterior table fractures. The control group was randomly sampled from patients who presented with a blunt forehead trauma in our institution's emergency unit. In computed tomography data sets, all patients' frontal sinus size was categorized by Guerram's classification that is defined as aplasia, hypoplasia, medium-size and hyperplasia. Odds for prevalence of the sinus types as well as sinus total width and height were compared between both groups.

RESULTS

In total, 47 cases and 93 controls were identified. Hyperplasia in the case group had an odds ratio of 46:1 (p < 0.001) compared to the controls. Mean sinus width (73 mm vs. 46 mm; p < 0.001) and sinus height (30 mm vs. 15 mm; p < 0.001) were larger in the case group.

CONCLUSION

Depressed traumatic fractures of the anterior table are an injury with a high risk specific for enlarged frontal sinus sizes. Anatomy is the predictive factor for this mode of craniofacial trauma.

Frontal Sinus Morphology: A Reliable Factor for Classification of Frontal Bone Fractures?

PURPOSE

The frontal sinus shows a wide range of morphologic variations. The aim of this study was to evaluate the influence of frontal sinus size on fracture characteristics in frontal bone trauma.

MATERIALS AND METHODS

In this cross-sectional study, data from patients with traumatic fractures of the frontal bone were retrospectively collected from the institution's database. Radiometric analysis of computed tomography and cone-beam computed tomography datasets was performed. Frontal sinus size was measured as variables of height, width, and depth. The secondary predictor was morphologic sinus type according to Guerram's classification: hyperplasia, medium size, hypoplasia, or aplasia of the frontal sinus. To determine outcomes, we classified fractures into the following categories: fracture isolated to the anterior table, combined fractures of the anterior and posterior tables, fracture isolated to the posterior table, and frontal bone fracture without sinus involvement. Further study variables were patients' demographic characteristics, combined midfacial fractures, orbital rim involvement, fracture displacement, and surgical approach. For statistical analysis, fracture types were assessed for frontal sinus metric size and morphologic type using bivariate tests with P < .05 defined as significant.

RESULTS

We enrolled 53 consecutive patients with a mean age of 35 years; male patients comprised 91%. Fracture types differed significantly in sinus width and height (both P < .001), as well as depth (P = .002). Frontal sinus morphology was hyperplastic in 66%, medium in 30.2%, and hypoplastic in 3.8%. Patients with a hyperplastic frontal sinus had an increased likelihood of isolated anterior table fractures (odds ratio, 6.0; P = .007) compared with medium-sized types. Fractures without sinus involvement were more likely in hypoplastic and medium types (P < .001).

CONCLUSIONS

The morphology of the frontal sinus determines the probability of fracture types from craniofacial trauma. Thus the frontal sinus size appears to be a major factor for frontal bone resistance to traumatic force impingement.