Changes in paranasal sinus volumes, temporal bone pneumatization, internal acoustic canal and olfactory cleft dimensions over the centuries: a comparison of skulls from different epochs in Anatolia.

OBJECTIVES: Investigating changes in temporal bone pneumatization (TBP) and paranasal sinus volumes (PSV) across different eras may help understanding not only changes in skull anatomy but also pathophysiology of chronic otitis media and sinusitis, respectively, which are common health problems. METHODS: Eight skulls from the second century AD, 20 skulls were from the 10th-11th centuries AD, 20 skulls from the 16th-19th centuries AD, and 60 contemporary skulls were included in this cross-sectional observational study. Using computerized tomography (CT) scans, the PSV were calculated by multiplying the height, width, and antero-posterior distance of the sinuses. TBP was divided into three types. Internal acoustic canal (IAC) length and width, and olfactory cleft (OC) width were measured. RESULTS: No statistically significant differences were found between the paranasal sinus (frontal, maxillary, and sphenoid) volumes between the groups. However, TBP decreased statistically significantly over time on both sides of the skulls (p = 0.001). The contemporary IAC and OC measures were found to be significantly lower on both sides compared to the skulls from the other three eras (p < 0.001 for both). CONCLUSIONS: Although no significant change was observed in PSV, decreases were evident in TBP, OC width and IAC length and width over time. It appears a fair inference that changes in size of OC and IAC might be another indication of the fact that olfaction and hearing were more vital for survival in old eras. Since we do not know incidence of chronic ear problems in old eras, we cannot speculate outcome of increased TBP in terms of developing chronic ear diseases. On the contrary, increased TBP was likely to play a protective role in traumas in old ears. Additionally, the environmental influences may be crucial role in the development of paranasal sinuses.

Jugular bulb anatomical variations and pneumatization patterns: a comprehensive CBCT analysis.

PURPOSE: This study aims to assess the anatomical possibilities of the jugular bulb (JB). METHODS: Fifty archived CBCT scans were analyzed. RESULTS: The average distance between the internal acoustic canal (IAC) and the JB was 7.97 mm on both sides (Right: SD = 2.56 mm, range 3.16-13.3 mm; Left: SD = 2.5 mm, range 2.9-13.6 mm). JB walls' pneumatization was classified into eight patterns. Deep petrosal cells (DPCs) prevailed in the lateral wall of the JB. The absence of pneumatization (NP) was commonly found on the left side. The presence of infralabyrinthine and hypotympanic cells varied. Less common types included accessory occipital cells (AOCs), posteromedial tracts (PMTs), and basi-occipital cells (BOCs), which determined a consistent variation of the lateral wall pneumatization patterns. Pneumatization of the medial wall was not observed in 50 right sides and 49 left sides. The inferior wall analysis revealed symmetry in AOC distribution and a predominant occurrence of NP. Cases with hypotympanum (HT) in the lateral wall showed a statistically significant IAC-JB distance increase by an average of 4.67 mm compared to NPs. Specific pneumatizations, particularly HT on the lateral side, have a significant effect on the IAC-JB distance, showing a clear pattern of increasing distance from DPC to NP and then to HT. A significant distance increase in HT pneumatization was noted. There were also recorded instances of JB hypoplasia and hyperplasia, JB diverticula, dehiscent JBs, and high JBs. CONCLUSION: This study establishes a novel classification of JB pneumatizations to aid in the understanding of the temporal bone anatomy.

The Role of Temporal Bone Pneumatization on Fracture Line and Involved Cranial Structures.

OBJECTIVE: Temporal bone pneumatization (TBP) is speculated to serve as a shock absorber in temporal bone fractures (TBF), directing the fracture line away from vital structures. This study correlates TBP extent with TBF patterns and preservations of vital TB structures. STUDY DESIGN: Retrospective cohort study. SETTING: Tertiary referral medical center. METHODS: All TBF patients referred to a single tertiary center 2017 to 2023 were evaluated. A pneumatization index score for each of their TBs was derived by counting automated-voxel density in a 0 to 100 scale. Results were correlated to the TBF type and the violated structure(s). The ossification index was compared to previously detailed qualitative classification systems of TBP. RESULTS: One hundred and forty-five patients were enrolled (mean age 43 ± 17 years). Kinematics were motor vehicle accidents (46%), scooter (15%), bicycle (14%), falls (13%), and assaults (8%). The mastoid ossification index we used showed a strong correlation to all qualitative classification systems (sigmoid = 0.829; labyrinthine = 0.849; carotis = 0.863, infralabyrinthine = 0.869, all P < .001). The pneumatization index strongly correlated with capsule-violating TBFs, with a mean of 44 ± 23 for otic capsule-sparing TBF and 61 ± 20 for otic capsule-violating (OCV) TBF (P < .001). The facial nerve was violated in 30 patients. Facial canal (FC) involvement was not correlated to the ossification index: it was 49 ± 23 for FC-sparing and 44 ± 23 for FC-violating (P = .620). CONCLUSION: TBP serves as a protective mechanism against OCV TBF. The more pneumatized the TB, the less likely the otic capsule will be violated in the event of a TBF with the exception of the carotid and FCs. TBP index is in strong agreement with qualitative TBP classification systems.

Assessment of the Anterior Clinoid Process and Optic Strut in Chiari Malformation Type I: A Computed Tomography Study.

Objective This study aimed to evaluate morphological features of the anterior clinoid process (ACP) and the optic strut (OS) in Chiari malformation Type I (CM-I). Methods The study universe consisted of computed tomography images of 41 CM-I patients and 45 normal subjects. Comparison of the parameters for CM-I and the control group was performed with the Student's t -test. A " p < 0.05" was accepted as the significance level. Results ACP length was smaller in CM-I than the control group ( p < 0.001). In contrast to ACP length, ACP angle ( p < 0.001), OS length ( p = 0.022), and the distance between ACP and OS ( p = 0.020) were found greater in CM-I in comparison to the control group ( p < 0.05). ACP width ( p = 0.233) and OS width ( p = 0.376) were similar in both groups. ACP pneumatization in CM-I group was found as 12.20%, whereas in the control group as 8.90%. Two different types about the pneumatization were identified in CM-I group (Type 1: 4.9% and Type 2: 7.3%), whereas three different types in the control group (Type 1: 3.3%, Type 2: 4.4%, and Type 3: 1.1%). Relative to ACP, three different types about OS position were identified in CM-I group (Type C: 31.70%, Type D: 64.60%, and Type E: 3.70%) and the control group (Type C: 7.80%, Type D: 64.40%, and Type E: 27.80%). Conclusion Shorter ACP, wide-angled ACP, longer OS, and more anteriorly located OS were found in CM-I group compared with the normal group. Our findings showed that the pneumatization of ACP was not affected by CM-I.

Development of Air Cell System Following Canal Wall Up Mastoidectomy for Pediatric Cholesteatoma.

Background: The development of temporal bone pneumatization is related to the postnatal middle ear environment, where the development of air cells is suppressed with otitis media in early childhood. However, whether air cell formation restarts when mastoidectomy is performed during temporal bone pneumatization remains unclear. Herein, we evaluated temporal bone pneumatization after canal wall up (CWU) tympanomastoidectomy for middle ear cholesteatoma in children. Methods: In total, 63 patients, including 29 patients with congenital cholesteatoma (CC) and 34 patients with acquired cholesteatoma (AC), were assessed using a set of pre- and postoperative computed tomography images. The air cells of the temporal bone were divided into five areas: periantral (anterior), periantral (posterior), periantral (medial), peritubal, and petrous apex. The number of areas with air cells before and after surgery was compared to evaluate temporal bone pneumatization after surgery. Results: A total of 63 patients, comprising 29 with CC and 34 with AC (pars flaccida; 23, pars tensa; 7, unclassified; 4), were evaluated. The median age of patients (18 males and 11 females) with CC was 5.0 (range, 2-15 years), while that of the AC group (23 males and 11 females) was 8 (range, 2-15 years). A significant difference in air cell presence was identified in the CC and AC groups after surgery (Mann-Whitney U, p < 0.001 and p = 0.003, respectively). Between the two groups, considerably better postoperative pneumatization was observed in the CC group. A correlation between age at surgery and gain of postoperative air cell area development was identified in the CC group (Spearman's rank-order correlation coefficient, r = -0.584, p < 0.001). In comparison with the postoperative pneumatization rate of each classified area, the petrous apex area was the lowest in the CC and AC groups. Conclusions: Newly developed air cells were identified in the temporal bones after CWU mastoidectomy for pediatric cholesteatoma. These findings may justify CWU tympanomastoidectomy, at least for younger children and CC patients, who may subsequently develop air cell systems after surgery.

Pneumatization types of the dorsum sellae: a computed tomography study.

PURPOSE: The present work aimed to classify the pneumatization of the dorsum sellae (DS) in subjects aged 1-90 years. METHODS: The study consisted of computed tomography images of 1080 subjects (582 males / 498 females), aged 1-90 years (mean age: 45.51 ± 26.06 years). Four different types regarding DS pneumatization were defined as follows: Type 0: no pneumatization, Type 1: pneumatization < 50%, Type 2: pneumatization > 50%, and Type 3: total pneumatization. RESULTS: DS pneumatization was identified in 354 (32.8%) subjects (189 males and 165 females). Its pneumatization was identified in 51 (21.2%) out of 241 children, and 303 (36.1%) out of 839 adults. The frequency of DS pneumatization types was found as follows: Type 0 (no pneumatization in 726 subjects, 67.2%) > Type 1 (pneumatization < 50% in 234 subjects, 21.6%) > Type 2 (pneumatization > 50% in 87 subjects, 8.1%) > Type 3 (total pneumatization in 33 subjects, 3.1%). DS pneumatization incidence was affected by ages (p < 0.001), but not sex (p = 0.818). The pneumatization degrees of DS (i.e., the distributions of Types 1-3) were not affected by ages (p = 0.637) or sex (p = 0.391). CONCLUSION: The pneumatization incidence of DS increased significantly with advancing adult ages (especially in elderly people). DS pneumatization should be taken into account by neurosurgeons and neuroradiologists to decrease the risk of complications such as cerebrospinal fluid fistula during surgeries such as posterior clinoidectomy.

Three-Dimensional Volumetric Investigation of Onodi Cells: A Multi-Slice Computed Tomography Study.

Introduction Onodi cells (OCs) are posterior ethmoid cells that are located above the sphenoid sinus, close to or even surrounding the carotid artery and optic nerve. Objective To investigate and evaluate the volumetric variation of OCs through multi-slice computed tomography (MSCT) scans. Methods We performed a retrospective review of MSCT scans of 79 subjects, 40 male and 39 female patients, Whose age ranged from 18 to 83 (mean: 39.6) years. The volumes of the OCs on the right and left sides were measured using the ITK-SNAP software (open-source) with semiautomatic segmentation. The possible relationships involving age, gender, contact with the optic nerve, extension of the pneumatization of the posterior ethmoid cells into the clinoid processes, mucous thickening in the anterior and posterior ethmoid cells, and obliteration of the sphenoethmoidal complex were analyzed with the Pearson correlation and Chi-squared tests according to the type of data compared and logistic regression models ( p < 0.05). Results We observed that an increase of one unit in the volume of OCs also increases the chance of extension of pneumatization into the clinoid processes by 0.15% ( p = 0.001). No significant correlations were identified regarding age, gender, and volume of the OCs. Conclusion The volume of the OCs has effects on the extension of pneumatization into the clinoid processes.

Evaluation of Dimensional Changes in Maxillary and Frontal Sinus in Adult Patients With Anterior Open Bite and Normal Overbite: A Retrospective Cone Beam Computed Tomography (CBCT) Study.

INTRODUCTION: An anterior open bite is a form of vertical discrepancy that presents as a lack of contact between maxillary and mandibular segments. The treatment modalities usually involve either intrusion of posterior teeth or extrusion of anterior or a combination of both. The anatomical relationship between the apex of the maxillary molar roots to the inferior wall of the maxillary sinus floor is crucial in planning posterior intrusion. The paranasal sinuses influence the growth of the facial structures that eventually get altered in various malocclusions. Studies have proven that the height of the sinus gets modified in anterior open bite owing to pneumatization. This study aims to evaluate the distance from the root apex of maxillary first molars (mesiobuccal, distobuccal, and palatal roots) to the maxillary sinus floor to evaluate the significance of the vertical pneumatization of the sinus on planning for true intrusion in anterior open bite and to assess the correlation between frontal and maxillary sinuses in an anterior open bite. METHODS: This retrospective study evaluated 30 pre-treatment cone beam computed tomographies (CBCTs) of patients out of which 15 were with anterior open bite and 15 with ideal overbite. Linear measurements were carried out using care stream software in CBCTs. RESULTS: There was a significant correlation between the distance of the palatal root and the distobuccal root of the maxillary first molar to the maxillary sinus floor bilaterally in the anterior open bite (p<0.04). A significant moderate positive correlation of the maxillary and frontal sinus height in anterior open bite (p<0.006). A significant moderate negative correlation between the distance from the palatal root to the maxillary sinus floor and maxillary sinus height in anterior open bite (p<0.001). CONCLUSION: Vertical pneumatisation of the maxillary sinus has caused a significant negative correlation between the apex of the palatal root of the maxillary first molar tooth and the maxillary sinus floor in the anterior open bite. The palatal root being the closest to the sinus floor, and the distobuccal root being second nearest. There is a significant correlation between the height of the sinuses in the anterior open bite.

Do Decreased Mastoid Pneumatization, Bilateral Involvement and Eustachian Tube Function Affect the Success of Type 1 Tympanoplasty?

Aim: The surgical success rate of tympanoplasty appears to be influenced by a number of variables. Eustachian tube dysfunction has been shown as one of the factors causing failure in tympanoplasty. It is known that bilateral disease and decreased in mastoid pneumatization are associated with Eustachian tube (ET) dysfunction. In this study, the relationship between the success of type 1 tympanoplasty and mastoid pneumatization, bilateral disease and ET function was investigated. Materials and Methods: A total of 44 patients who were operated for chronic otitis media in our clinic were included. The information of the patients was obtained retrospectively, the direction of the disease (bilateral/unilateral), the status of the graft (intact/perforated), mastoid pneumatization status, and hearing levels (preoperative/postoperative 6th month) were noted. Automatic Williams test was used to tympanometrically evaluate ET functions (ETF) in postoperative period. The relationship between tympanoplasty success and mastoid pneumatization, bilateral disease and ETF was investigated by statistical analysis. Results: The disease aspect was found bilateral in 34.1% (n = 15) of the cases, and unilateral in 65.9% (n = 29) of the cases. Mastoid pneumatization was decreased in 52.2% (n = 23) of the cases, and normal in 45.4% (n = 20). The preoperative air-bone mean difference (gap) of the cases with decreased mastoid pneumatization was found to be statistically significantly higher than the cases with normal mastoid pneumatization (p < 0.05). The closure of the postoperative air-bone gap in patients with unilateral disease direction was found to be statistically significantly higher than in patients with bilateral disease direction (p < 0.05). Also we found significantly worse ET functions both in unilateral and bilateral disease. Conclusion: Preoperative air-bone gap average is higher in ears with decreased mastoid pneumatization, and postoperative air-bone gap closure is higher in unilateral patients. Mastoid ventilation does not make a significant difference in the success of type 1 tympanoplasty. On the other hand, our results support that ET dysfunction can be effective in the occurrence of chronic otitis media (COM).

Unravelling the Complex Relationship Between Frontal Sinus Pneumatization and Paranasal Sinus Anatomical Variants: Insights from CT Imaging.

The aim of this study was to analyse the relationship between frontal sinus pneumatization and its effect on various variations of paranasal sinuses on paranasal sinus CT scan. A total number of 100 patients (51 males, 49 females) were included in this study. Patients were divided into three groups on the basis of their frontal sinus pneumatization extent on paranasal sinus CT as Type 1 pneumatization (aplasia and hypoplasia), Type 2 pneumatization (medium) and Type 3 pneumatization (hyperplasia). The prevalence of various variations like pneumatization of upper and middle turbinate, presence of agger nasi, Haller and Onodi cell, maxillary sinus hypoplasia, extent of sphenoid sinus pneumatization, pneumatization of anterior clinoid process, pterygoid process and greater wing of sphenoid sinus, dehiscence and protrusion of internal carotid artery and optic nerve types were ascertained and compared within each group. The prevalence of Onodi cell, anterior clinoid process and greater wing of sphenoid pneumatization and optic nerves type 3 and 4 were higher in Type 3 frontal sinus pneumatization group as compared with other groups. Excessive pneumatization of frontal sinus has various effects on paranasal sinus variations. Surgeons dealing with endoscopic sinus surgery, maxillofacial and skull base surgery must be vigilant of association between these variations preoperatively for avoiding complications.

Multiple coexisting variations of skull and cervical spine anatomy in a symptomatic patient - uncommon or uncommonly noticed? A CT-based case study.

INTRODUCTION: Among many anatomical variations of the skull and cervical spine, some may be an underlying cause of a disease, while others remain clinically silent. The estimated individual prevalences of them differ, but given the available data it is impossible to clarify how frequently they coexist with each other. The following study presents an example of seven anomalies, amongst which at least few have manifested clinically in the examined patient. CASE REPORT: A 35 y.o. Polish woman who suffered from chronic sinusitis was subjected to a computed tomography scan. Mild thickening of the anterior ethmoidal cells' mucosa, bilateral concha bullosa, paradoxical right middle turbinate, bilateral uncinate process pneumatization and arrested pneumatization of sphenoid sinus were found and addressed in context of the reported symptoms. Simultaneously other, clinically silent anatomical anomalies, were found - namely ossification of the anterior petroclinoid ligament, incomplete medial basal canal and bilateral arcuate foramen. CONCLUSION: To the best knowledge of the authors, this case report is the first to present such a coexistence of this many various anatomical anomalies, among which some played a crucial part in the chronic sinusitis experienced by the patient. Concurrence of multiple variations in the same anatomical area or functional unit may exacerbate clinical presentation of a patient. Identifying a single anomaly ought to warrant a thorough investigation into any other potentially existing variants.

Is there a relationship between sphenoid sinus pneumatization and carotid canal-intersinus septa connection?

OBJECTIVES: We investigated the relationship between sphenoid sinus (SS) pneumatization types, carotid canal types and carotid canal-intersinus septa connection. METHODS: The paranasal sinus computed tomography (PNSCT) images of 274 patients (141 males and 133 females) were evaluated retrospectively. SS pneumatization, SS intersinus septation, SS intersinus septa deviation, carotid canal classification, carotid canal dehiscence, carotid canal-intersinus septa connection and presence of Onodi cells were evaluated. RESULTS: In presellar and sellar SS, type 1 carotid canal was detected. However, type 3 carotid canal was detected more in postsellar SS. On the left side, in 26.4% of the postsellar SS, carotid canal dehiscence was detected. On the right side, carotid canal-intersinus septa connection was detected in 55.8% of the postsellar SS and 35.1% of the sellar SS. On the left side, it was detected 58.3% of the postsellar SS and 30.9% of the sellar SS. In postsellar type SS pneumatized cases, right caroid canal-intersinus septa connection increased by 5.4 fold and left carotid canal-intersinus septa connection increased by 7.3 fold compared to presellar type SS pneumatization. In 2≥ intersinus septa group, left carotid canal-intersinus septa connection increased 5.0 fold compared to 'no septa' group. CONCLUSION: In this study, we evaluated SS pneumatization types and their relation with carotid canal types and carotid canal-intersinus septa connections. Type 3 carotid canal (protrudation to SS wall) was detected more in postsellar SS. In these cases, surgeons should be very careful during surgery to avoid damage to the internal carotid artery (ICA).

Three-dimensional volumetric analyses of temporal bone pneumatization from early childhood to early adulthood in a South African population.

BACKGROUND: A debate exists on whether the size of temporal bone pneumatization is a cause or consequence of otitis media (a global disease burden). However, a normal middle-ear mucosa is a prerequisite for normal temporal bone pneumatization. This study investigated the size of temporal bone pneumatization with age and the normal distribution of air cell volume in different stages of human growth postnatally. MATERIALS AND METHODS: A three-dimensional computer-based volumetric-rendering technique was performed bilaterally on 248 head/brain and internal acoustic meatus computed tomography images of slice thickness ≤ 0.6 mm consisting of 133 males and 115 females with age range 0-35 years. RESULTS: The average volume of infant (0-2 years) pneumatization was 1920 mm3 with an expected rapid increase to about 4510 mm3 in childhood (6-9 years). The result also showed a significant increase (p < 0.001) in the volume of air cells up to the young adult stage I (19-25 years), followed by a significant decline in young adult stage II (26-35 years). However, the females were observed to experience an earlier increase than males. Also, population differences were observed as the Black South African population group showed a higher increase in volume with age than the White and Indian South African population groups, though the volumes of the latter increased up to young adult stage II. CONCLUSIONS: This study concludes that the pneumatization of a healthy temporal bone is expected to continue a linear increase up until at least adult stage I. Termination of temporal bone pneumatization in an individual before this stage could signify pathologic involvement of the middle ear during childhood.

Evaluation of the Sigmoid Sinus Morphology by Cone Beam Computed Tomography; Touchstone of the Posterior Cranial Fossa.

OBJECTIVE: In this study, we aimed to analyze the relationship of the sigmoid sinus (SS) with the external auditory canal, facial nerve, and mastoid cells from an anatomic point of view, to define the position of the SS during transmastoid, translabyrinthine, retrosigmoid (lateral suboccipital) approaches, in tympanomastoidectomy and posterior cranial fossa surgery. METHODS: In this study, the morphologic structures associated with the sigmoid sinus were evaluated in cone beam computed tomography images taken between 2015 and 2022. The images of 68 men and 106 women, aged 18-65 years, obtained from the archive of Ankara University Faculty of Dentistry, Department of Oral and Maxillofacial Radiology were analyzed. RESULTS: The most common SS pattern was type II, with a rate of 60.8% (n = 209); the second was type III, with 20.6% (n = 71); and the least common was type I, with 18.6% (n = 64). Although the distance between the horizontal line passing through the external auditory canal and facial nerve and the anterior contour of the SS was highest in type I (right, 7.26 ± 1.62; left, 7.44 ± 0.97), it was lowest in type III (right, 4.40 ± 1.50; left, 4.84 ± 1.16) (P < 0.05). CONCLUSIONS: This study highlights the importance of the SS position in surgery, with special reference to otologic, neurotologic, and posterior cranial fossa surgery. To avoid intraoperative complications, each patient should be evaluated preoperatively by appropriate radiologic methods.

Three-Dimensional Volumetric Investigation of Onodi Cells: A Multi-Slice Computed Tomography Study

Abstract Introduction Onodi cells (OCs) are posterior ethmoid cells that are located above the sphenoid sinus, close to or even surrounding the carotid artery and optic nerve. Objective To investigate and evaluate the volumetric variation of OCs through multi-slice computed tomography (MSCT) scans. Methods We performed a retrospective review of MSCT scans of 79 subjects, 40 male and 39 female patients, Whose age ranged from 18 to 83 (mean: 39.6) years. The volumes of the OCs on the right and left sides were measured using the ITK-SNAP software (open-source) with semiautomatic segmentation. The possible relationships involving age, gender, contact with the optic nerve, extension of the pneumatization of the posterior ethmoid cells into the clinoid processes, mucous thickening in the anterior and posterior ethmoid cells, and obliteration of the sphenoethmoidal complex were analyzed with the Pearson correlation and Chi-squared tests according to the type of data compared and logistic regression models (p < 0.05). Results We observed that an increase of one unit in the volume of OCs also increases the chance of extension of pneumatization into the clinoid processes by 0.15% (p = 0.001). No significant correlations were identified regarding age, gender, and volume of the OCs. Conclusion The volume of the OCs has effects on the extension of pneumatization into the clinoid processes.

Growth and microanatomy of the paranasal sinuses in two species of New World monkeys.

Paranasal sinuses of living apes and humans grow with positive allometry, suggesting a novel mechanism for bone enlargement. Here, we examine the paranasal sinuses of the owl monkey (Aotus spp.) and a tamarin (Saguinus midas) across postnatal development. The prediction that paranasal sinuses grow disproportionately faster than the main nasal chamber is tested. We used diffusible iodine-based contrast-enhanced computed tomography and histology to study sinuses in eight Aotus and three tamarins ranging from newborn to adult ages. Sinuses were segmented at the mucosa-air cavity interface and measured in volume. All sinuses were lined by a ciliated respiratory epithelium, except for the ethmoid air cells in Aotus, which are lined in part by olfactory epithelium. An age comparison indicates that only the maxillary sinus and ethmoid air cells are present in newborns, and two additional sinuses (invading the orbitosphenoid and the frontal bone), do not appear until late infancy or later. Comparing newborns and adults, the main nasal airway is 10 times larger in the adult Aotus and ~ 6.5 times larger in adult Saguinus. In contrast, the maxillary sinus far exceeds this magnitude of difference: 24 times larger in the adult Aotus and 46 times larger in adult Saguinus. The frontal sinuses add significantly to total paranasal space volume in both species, but this growth is likely delayed until juvenile age. Results suggest ethmoid air cells expand the least. These results support our prediction that most paranasal sinuses have a distinctly higher growth rate compared to the main nasal chamber.

The Associations between the Maxillary Sinus Volume, Infraorbital Ethmoid Cells, and the Infraorbital Canal: A CT-Based Study.

This CT-based study aimed to characterize and explain the existence of two anatomical structures positioned near the maxillary sinuses, which are of clinical relevance in rhinology and maxillofacial surgery. A total of 182 head scans (92 males and 90 females) were inspected for infraorbital ethmoid cells (IECs) and for the type (route) of infraorbital canal (IOC). The maxillary sinuses were segmented, and their volumes were measured. Statistical analysis was conducted to reveal the associations between the two anatomical variations, namely, sex and the maxillary sinus volume. Infraorbital ethmoid cells were noted in 43.9% of the individuals studied; they were more frequent in males (53.3%) than in females (34.4%). The descending infraorbital nerve (type 3 IOC) was found in 13.2% of individuals and was independent of sex. Infraorbital ethmoid cells were associated with the IOC types. The maxillary sinus volume was found to be sex-dependent. A large sinus volume is significantly associated with IOC Type 3 (the descending canal) and the presence of IEC. Dentists, radiologists, and surgeons should be aware that individuals with extensive pneumatization of the maxillary sinuses are more likely to display a descending IOC and IEC. These findings should be studied, along with CT scans, before treatment and surgery.

Evaluation of the Radiological Anatomy of the Temporal Bone Air Spaces and Morphometric Analysis in Turkish Healthy Adults / Evaluación de la Anatomía Radiológica de los Espacios Aéreos del Hueso Temporal y Análisis Morfométrico en Adultos Turcos Sanos

SUMMARY: The temporal bone is a complicate structure which located on the lateral skull. The objective of the present study was to determine the temporal bone air spaces' morphometry, morphology, and pneumatization in Turkish healthy adult people. This retrospective observational study was carried out from 82 subjects (47 males, 35 females) aged 18-69 years. The external auditory canal and related structures' diameters and the volume of these areas were evaluated. The means and standard deviations of the Meatus acusticus externus length (MAEL), meatus acusticus externus pars cartilaginea length (MAEcL), meatus acusticus externus pars ossea length (MAEoL), meatus acusticus externus pars cartilaginea surface (MAEcS), meatus acusticus externus pars ossea surface (MAEoS), meatus acusticus externus volume (MAEV), meatus acusticus externus pars cartilaginea volume (MAEcV), meatus acusticus externus pars ossea volume (MAEoV), processus mastoideus air cells volume (PMACV), cavum tympani volume (CTV), and temporale pneumatic spaces volume (OTPSV) were found as 23.21±3.70 mm, 12.69±3.72 mm, 7.80±3.70 mm, 669.89±107.7 mm2, 267.50±30.51 mm2, 743.50±119.6 mm3, 971.97±156.69 mm3, 419.51±48.67 mm3, 5915.93±650.34 mm3, 673.48±91.93 mm3, 7813.34±717.49 mm3 have found in 82 subjects, respectively. In this paper, the morphometric and volume properties of the temporal bone cavities measurements were significantly higher in males than females. These results may both provide reference values of Turkish healthy population, and lead to decrease potential surgical complications about temporal and mastoid regions.

El hueso temporal es una compleja estructura ubicada en el parte lateral del cráneo. El objetivo del presente estudio fue determinar la morfometría, morfología y neumatización de los espacios aéreos del hueso temporal en individuos adultos turcos sanos. Este estudio observacional retrospectivo que se llevó a cabo en 82 sujetos (47 hombres, 35 mujeres) de entre 18 y 69 años. Se evaluaron los diámetros del meato acústico externo y las estructuras relacionadas y el volumen de estas áreas. Las medias y las desviaciones estándar de la longitud del meato acústico externo (MAEL), la longitud de la parte cartilaginosa del meato acústico externo (MAEcL), la longitud de la parte ósea del meato acústico externo (MAEoL), la superficie de la parte cartilaginosa del meato acústico externo (MAEcS), la superficie de la parte ósea del meato acústico externo (MAEoS), volumen del meato acústico externo (MAEV), volumen de la parte cartilaginosa del meato acústico externo (MAEcV), volumen de la parte ósea del meato acústico externo (MAEoV), volumen de las células aéreas del proceso mastoideo (PMACV), volumen del cavum tympani (CTV) y el volumen de los espacios neumáticos temporales (OTPSV) se encontró como 23,21 ± 3,70 mm, 12,69 ± 3,72 mm, 7,80 ± 3,70 mm, 669,89 ± 107,7 mm2, 267,50 ± 30,51 mm2, 743,50 ± 119,6 mm3, 971,97 ± 156,69 mm3, 419,5. 1±48,67 mm3, 5915,93 ± 650,34 mm3, 673,48 ± 91,93 mm3, 7813,34 ± 717,49 mm3, respectivamente. En este artículo, las propiedades morfométricas y de volumen de las mediciones de las cavidades del hueso temporal fueron significativamente mayores en hombres que en mujeres. Estos resultados pueden proporcionar valores de referencia de la población sana turca y conducir a una disminución de las posibles complicaciones quirúrgicas en las regiones temporal y mastoidea.

Computed tomography-based assessment of sphenoid sinus and sella turcica pneumatization analysis: a retrospective study.

Background: A preoperative three-dimensional examination of the sphenoid sinus anatomy, its pneumatization pattern, and its relevance to neighboring neurovascular constructions is crucial to preventing possible complications. In this study, the aim was to evaluate the relationship between sphenoid sinus pneumatization types and the sella turcica using computed tomography (CT). Methods: CT data from 420 patients referred to the Department of Dentomaxillofacial Radiology were evaluated retrospectively. Sella pneumatization types were classified as conchal, presellar, incomplete sellar, and complete sellar, and they were evaluated. Obtained data were evaluated using the IBM SPSS 25.0 (Armonk, New York, USA) package program. Results: CT images of 420 individuals, including 174 women and 246 men with a mean age of 43.87 ± 17.58 years, were included in the study. When the sella turcica morphologies were evaluated, the most widespread morphological type was irregularity in the posterior part of the dorsum sella, in 51.2% of cases. In addition, a statistically significant correlation was found between the pneumatization of the sphenoid sinus and the morphological types of sella (p < 0.05). Conclusion: In this research endeavor, the predominant observation comprised the complete sellar sphenoid sinus pneumatization type, exhibiting irregularity in the posterior aspect of the dorsum sella, representing one of the sellar types. Notwithstanding, it is imperative to conduct additional investigations to establish the generalizability of the present study's findings.

Prevalence of zygomatic air cell defects in a North American population.

Zygomatic air cell defects (ZACDs) are asymptomatic defects present in the zygomatic process and articular eminence of the temporal bone. This defect is considered a normal anatomical variant and can be detected on routine panoramic images. The objective of this study was to determine the prevalence, dominant type, and location of ZACDs in a North American population. A total of 1724 panoramic images of adult patients were analyzed by a third-year dental student in conjunction with an oral and maxillofacial radiologist. Patient demographics (age and sex) as well as ZACD location (unilateral right/left or bilateral) and appearance (unilocular or multilocular) were evaluated. Statistical analyses included the Clopper-Pearson method to calculate the 95% CI, Student t test for independent samples, and Fisher exact test. The prevalence of ZACDs in this study population was 2.1%. A total of 24 women (2.3%) and 12 men (1.7%) were affected, with no statistically significant difference between the sexes. The mean (SD) age of patients presenting with a ZACD was 56.6 (17.7) years, while that of patients without a ZACD was 53.0 (16.3) years, with no statistically significant difference between groups. Among the 36 patients with ZACDs, 28 (1.6%) had unilateral and 8 (0.5%) had bilateral lesions. One patient with bilateral ZACDs had a unilocular lesion on the right side and a multilocular lesion on the left, so there were a total of 31 unilocular lesions (1.8%) and 6 multilocular lesions (0.3%). The results of this study indicate that the prevalence of ZACDs in the study population was 2.1%, without any statistically significant differences based on the sex or age of the patient or laterality or appearance of the lesions.