Classification of crista galli pneumatization and clinical considerations for anterior skull base surgery

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.

A comparative analysis of the CP and CG using 2D and 3D visualisation approaches

Investigations on the structural variations in the cribriform plate (CP), olfactory foramina and the Crista Galli showcase the benefits of using 3D imaging on smaller structures. These techniques reveal accurate details about bone morphology and density. Comparing different techniques, this project aims to examine the correlation between the CP, olfactory foramina, and Crista Galli. Computed tomography was used to translate and apply the findings acquired from the samples in radiographic studies on CPs for potential clinical significance. The findings show that the surface area measurements were significantly larger when using 3D imaging techniques in comparison with the 2D counterpart. Using 2D imaging, the maximum surface area of the CPs was 239.54 mm², however, paired 3D samples showed the maximum surface area was 355.51 mm². The findings show that Crista Galli's dimensions varied greatly, with length ranging from 15 to 26 mm, height ranging from 5 to 18 mm, and width ranging from 2 to 7 mm. The 3D imaging allowed for surface area measurements on the Crista Galli, and the surface area ranged from 130 to 390 mm². When 3D imaging was used, significant correlations were found between the surface area of the CP and the length of the Crista Galli (p = 0.001). The findings show that measurements on the Crista Galli using 2D and 3D reconstructed radiographic imaging reflect similar ranges of dimensions to 3D imaging measurements. The findings also suggest that the Crista Galli may increase in length with the CP to support the latter and olfactory bulb during trauma which may be used by clinicians alongside 2D CT scans for optimal diagnosis.

A comprehensive morphometric analysis of crista galli for sex determination with a novel morphological classification on computed tomography images

PURPOSE

This study aimed to examine the morphometry of the crista galli (CG) on paranasal sinus computed tomography (PNCT) images to develop a new approach of morphological classification with objective radiological criteria and to investigate the relationship of morphometric and morphological characteristics with gender.

METHODS

The height, width, and length of the CG were measured on the PNCT images of 533 subjects (266 males, 267 females). Based on the dimensions and the presence of the cavitary component of the CG, the CG was classified into three morphological types. The success of CG dimensions and new morphological classification of CG in the determination of gender was evaluated with ROC and Paired Logistic Regression analyses.

RESULTS

The morphometric cutoff values of the height, width, and length of the CG for the estimation of gender were determined as 15.15, 3.45, and 13.25 mm, respectively. CG length (accuracy 83.7%) showed more successful classification rate on gender determination as compared to height (accuracy: 81.4%), and width (accuracy 81.2%) of the CG. The presence of ossified type CG accurately identified the male sex at a rate of 88.7%, and teardrop type CG determined female sex at a rate of 82.9%. Tubular type CG identified male sex correctly at the rate of 65.8%.

CONCLUSION

The height, length, and width measurements of CG on PNCT images and the new morphological types recommended in this study can be used in the determination of gender with high accuracy rates.