Computed Tomographic Study of Remarkable Anatomic Variations in Paranasal Sinus Region and their Clinical Importance - A Retrospective Study

Sinonasal Anatomic Variations in the Adult Population: CT Examination of 1200 Patients

BACKGROUND

The nasal cavity and paranasal sinuses are one of the most frequently anatomically varied regions. Their size and shape vary from person to person, and ethnic origin may have a role in this variety. Recognizing this variations is so important for ear nose throat (ENT) specialists because they predispose to sinonasal pathologies and affect the complication rate and success of endoscopic sinus surgery.

AIM

This study aimed to determine the frequency of sinonasal anatomic variations on paranasal sinus computed tomography (CT) in the Turkish population.

METHODS

Patients who had undergone paranasal sinus CT with any complaints between 2013 and 2020 and aged over 18 years were included in the study. A total of 1209 patients who had undergone paranasal sinus CT were examined for coronal, axial, and sagittal plans retrospectively by two ENT professionals, and anatomical variations were evaluated. To assign the frequency of anatomic variations in a healthy population, patients who had previously undergone paranasal sinus and nasal surgery, who had nasal polyposis, and for whom CT evaluation was not possible due to intense sinusitis were excluded from the study.

RESULTS

Among 1209 patients, 644 were male and 565 were female. The mean age of the patients was 33.7 years. The most common sinonasal anatomical variations were nasal septal deviation and agger nasi cells, while the least common variation is the supreme turbinate. No variation was found in 48 (3.9%) CTs.

CONCLUSION

Almost all patients had at least one sinonasal anatomical variation. These variations should be known by the professionals who have interest in sinonasal disease and surgery.

Radiological anatomical variations of the lateral nasal wall and anterior skull base amongst different populations: A systematic review and meta-analysis

OBJECTIVES

To determine the anatomical variations of the lateral nasal wall and anterior skull base amongst populations in different geographical regions.

DESIGN

Systematic review and meta-analysis.

METHODS

Using PRISMA guidelines, SCOPUS and PUBMED databases were searched from inception until 1 March 2022. The regions and populations identified were from Europe, Asia, Middle East, Australia-New Zealand-Oceania, South America, North America and Africa. Random-effects model was used to estimate the pooled prevalence with 95% confidence intervals (CIs). Heterogeneity was assessed using the I² statistic and Cochran's Q test.

MAIN OUTCOME MEASURES

Anatomical variations of the lateral nasal wall and anterior skull base confirmed by computed tomography scan.

RESULTS

Fifty-six articles were included with a total of 11 805 persons. The most common anatomical variation of the ostiomeatal complex was pneumatization of the agger nasi (84.1%), olfactory fossa was Keros type 2 (53.8%) and ethmoids was asymmetry of the roof (42.8%). Sphenoethmoidal and suprabullar cells have a higher prevalence in North Americans (53.7%, 95% CI: 46.00-61.33) while asymmetry of ethmoid roof more common in Middle Easterns (85.5%, 95% CI: .00-100). Bent uncinate process has greater prevalence in Asians while supraorbital ethmoid cells and Keros type 3 more common in non-Asians. The overall studies have substantial heterogeneity and publication bias.

CONCLUSION

Certain anatomic variants are more common in a specific population. The 'approach of analysis' plays a role in the prevalence estimates and consensus should be made in future studies regarding the most appropriate 'approach of analysis' either by persons or by sides.

Incidence of maxillary sinus septa in the saudi population

BACKGROUND

The variability in the maxillary sinus anatomy makes dental implant planning challenging. One of the anatomical landmarks that could affect the decision for implant placement around the maxillary sinus is the sinus septa. This study aimed to retrospectively determine the prevalence, anatomical distribution, and morphology of the maxillary sinus septa.

MATERIALS AND METHODS

This study included 309 CBCT images that were analyzed to determine the prevalence, height, location, and orientation of the maxillary sinus septa. Descriptive statistics, Mann‒Whitney U tests, and Kruskal‒Wallis tests were used for data analysis.

RESULTS

A total of 618 maxillary sinuses were analyzed. Maxillary septa were present in 30% (n = 188) of the sinuses and in approximately 45% of the analyzed images. The mean height of the septa was 5.09 mm. The presence of bilateral septa was evident in 49 subjects (35.25%). Female subjects were significantly more likely to have only one septum (n = 67, 53.6%, p < 0.05).

CONCLUSION

The presence of septa is very common, found in one-third to approximately half of the evaluated cases, which warrants careful examination before any surgical interventions to avoid possible complications.