Hyperaeration of the frontal sinus

Internal structural analysis of the nasomaxillary complex in patients with skeletal class III asymmetry: A study on asymmetry patterns

OBJECTIVES

To investigate the internal structure of the nasomaxillary complex, including the maxillary sinus, nasal cavity and nasal septum according to the facial asymmetry pattern and to evaluate its correlation with external maxillomandibular asymmetry in Class III patients based on cone-beam computerized tomography (CBCT) images.

MATERIALS AND METHODS

Facial asymmetry was analysed in a total of 100 Class III patients aged 16 years or older using CBCT scans. Patients were categorized into subgroups based on asymmetry pattern. Measurements of the nasomaxillary complex were obtained from the CBCT scans, including the volume and width of the maxillary sinuses and nasal cavities on deviated and non-deviated sides, as well as the displacement of the nasal septum. Statistical analysis was performed to compare the internal nasomaxillary variables within and between groups, and regression analysis was conducted to evaluate the correlation between facial asymmetry and the internal nasomaxillary variables.

RESULTS

Group comparisons showed that there were no significant differences in the volume of the maxillary sinus and nasal cavity. However, the direction and extent of nasal septum deviation, as well as the width of the nasal cavity, varied depending on the maxillary asymmetry pattern. Regression analysis indicated a correlation between nasal septum deviation and the difference in maxillary height, while the difference in nasal cavity width was correlated with the difference in maxillary width.

CONCLUSION

A comprehensive evaluation of the internal nasal anatomy is vital for understanding the intricate relationship between nasal structure and maxillary growth.

Frontal sinus pneumatisation: an isolated finding or a sign of concomitant anatomical variation?

OBJECTIVE

To determine the association between frontal sinus pneumatisation and concomitant anatomical variations in paranasal sinuses as seen on computed tomography.

METHODS

A total of 403 patients who underwent paranasal sinus computed tomography were allocated to three groups according to the degree of frontal sinus pneumatisation (type 1 - hypoplasia; type 2 - medium size; and type 3 - hyperplasia). In this unique model, the prevalence of ipsilateral variations on paranasal sinuses on each side of the head were analysed separately within each pneumatisation group.

RESULTS

The type 3 frontal sinus pneumatisation group showed a greater association with ipsilateral variations of the sphenoid bone. Variations included pneumatisation of the anterior clinoid process, lateral sphenoid recess, pterygoid process and greater wing, and exposure of Vidian canal. This group also showed significant associations with male gender, and the presence of frontal and Onodi cells.

CONCLUSION

Interpretation of the paranasal sinus variations is imperative for pre-operative evaluation in functional endoscopic sinus surgery, particularly in patients with frontal sinus hyperplasia. Attention to variation on the ipsilateral side is informative.

Paranasal sinus volumes and headache: is there a relation?

PURPOSE

The aim of the study is to investigate the relation between paranasal sinus volumes and headache in patients with no other rhinologic causes.

METHODS

Two hundred patients with chronic headache and 99 subjects with no headache or facial pain history in the last 6 months were included in the study. Paranasal computed tomography (CT) scans of both patient and control groups were evaluated. Sixty one patients were excluded from the study due to possible rhinogenic headache CT findings such as secretions and contact points. Sinus volume index (SVI) formula created by Barghouth et al. in 2002 was used to calculate paranasal sinus volumes: SVI = ½. A × B × C. Mann-Whitney U test was used to compare an independent continuous variable and a continuous variable with non-normal distribution.

RESULTS

In the patient group, the total sinus, frontal sinus, and maxillary sinus volumes were found to be significantly lower than those of the control group (p < 0.001). Although the total sphenoid sinus volume was found to be lower in the patient group, there was no significant difference between the two groups (p = 0.013).

CONCLUSION

Although rhinogenic findings are often related to secondary headache, the relation between paranasal sinus volume and headache is scarcely investigated in the literature. Our study showed that paranasal sinus volumes might have a role in secondary headaches. Furthermore, in contrast to the literature, our study showed a significant relation between headache and smaller paranasal sinus volumes.

Anatomical variations of the frontal sinus and its relationship with the orbital cavity

The anatomy of the frontal sinus is highly variable and its variations affect the occurrence/course of pathological processes. We investigated its size and relationship to the orbit, searching for patterns that would allow it to be classified anatomically. Cone beam computed tomography was applied to 91 skulls (age range 21-86 years) to determine sinus height, width, length, and length of contact with the orbit in the coronal and sagittal planes. In addition, orbital roof pneumatization in the coronal plane was categorized as: none; only medial part pneumatized; the medial and a portion of the central part pneumatized; roof predominantly pneumatized. Sinus dimensions varied widely (mm): height 6.2-50.0; width 3.7-54.0; length 2.4-45.0; frontal orbital contact 4.0-41.6; sagittal orbital contact 0.0-41.2. Pneumatization of the orbital roof (coronal plane) mostly affected the medial and a portion of the central part (50%), or the roof was predominantly pneumatized (32%). Three "types" of sinus (cluster analysis) were distinguished by the extent of pneumatization of the orbital roof in the coronal plane: "small", pneumatization absent or only of the medial part; "medium-sized", pneumatization of the medial and a portion of the central part; "large", roof predominantly pneumatized. All dimensions were significantly different among the types (P < 0.001). Sinus type was fairly predictive of the extent of contact with the orbit in the sagittal plane (not routinely assessed clinically). The data confirm the variability of frontal sinus anatomy and suggest a simple and straightforward classification with potential clinical relevance. Clin. Anat. 31:576-582, 2018. © 2017 Wiley Periodicals, Inc.

The classification of frontal sinus pneumatization patterns by CT-based volumetry

PURPOSE

We aimed to define the classification of frontal sinus pneumatization patterns according to three-dimensional volume measurements.

METHODS

Datasets of 148 sides of 74 dry skulls were generated by the computerized tomography-based volumetry to measure frontal sinus volumes. The cutoff points for frontal sinus hypoplasia and hyperplasia were tested by ROC curve analysis and the validity of the diagnostic points was measured.

RESULTS

The overall frequencies were 4.1, 14.2, 37.2 and 44.5 % for frontal sinus aplasia, hypoplasia, medium size and hyperplasia, respectively. The aplasia was bilateral in all three skulls. Hypoplasia was seen 76 % at the right side and hyperplasia was seen 56 % at the left side. The cutoff points for diagnosing frontal sinus hypoplasia and hyperplasia were '1131.25 mm(3)' (95.2 % sensitivity and 100 % specificity) and '3328.50 mm(3)' (88 % sensitivity and 86 % specificity), respectively.

CONCLUSIONS

The findings provided in the present study, which define frontal sinus pneumatization patterns by CT-based volumetry, proved that two opposite sides of the frontal sinuses are asymmetric and three-dimensional classification should be developed by CT-based volumetry, because two-dimensional evaluations lack depth measurement.

Mucosal contact points and paranasal sinus pneumatization: Does radiology predict headache causality?

OBJECTIVES/HYPOTHESIS

The goal of this study was to evaluate the prevalence of mucosal contact points (MCP), concha bullosa (CB), and variable paranasal sinus (PNS) volumes among patients sent for rhinogenic headache workup as compared with controls.

STUDY DESIGN

Retrospective study with case and control groups.

METHODS

Fifty-three adults with clear PNS computed tomography (CT) scans were included: 28 patients who have originally undergone PNS CT scan as part of sinus (rhinogenic) headache workup, and 25 controls in whom PNS CT scans were obtained for other purposes. All subjects were asked to report their symptoms using a headache scoring system. CT scans of all subjects were analyzed for presence of MCP, CB, as well as for volumes of maxillary, frontal, and sphenoid sinuses.

RESULTS

MCP was found in 40% of controls, and in 50%, 50%, and 40% of mild, moderate, and severe headache groups, respectively. CB was found in 24% of controls, and in 33.3%, 58.3%, and 20%, of mild, moderate, and severe headache groups, respectively. Total volume of the measured PNS ranged from 23.9 to 81.4 cm(3) (mean ± standard deviation [SD], 48.3 ± 15.8) in the control group and from 5.31 to 87.4 cm(3) (mean ± SD, 43.6 ± 16) in the patient group. No statistically significant difference was found between groups regarding all studied variables.

CONCLUSIONS

Radiological identification of MCP, CB, or hyperpneumatized sinuses does not seem to be a predictor of headache causality. Further studies are required to identify clinical scenarios in which these variations may contribute to pain symptoms.

LEVEL OF EVIDENCE

3b.

Excessive paranasal sinuses and mastoid aeration as a possible cause of chronic headache

The objective of this case report is to present a patient with chronic headache who was diagnosed with excessive aeration of all paranasal sinuses and mastoid air cells using computed tomography imaging. The volume and linear measurements of all of the cavities revealed values greater than the greatest values reported in the literature. To date, this is the second reported case of excessive enlargement of all paranasal sinuses and the first which includes the enlargement of the mastoid air cells. No surgical intervention was required for the patient, but in similar cases, with more severe symptoms, surgical treatment is a challenge for the surgeon and may mandate a multidisciplinary approach.