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Published on: March 1, 2024
Age-dependent differences of the depth of olfactory fossa in children
Mehmet Güven1, Halil Elden1, Atılay Yaylacı2
1Sakarya University, Faculty of Medicine, Department of Otorhinolaryngology, Sakarya, Turkey.
Insights
This study analyzed olfactory fossa depth in pediatric patients using Keros classification. Findings reveal age-related variations, suggesting potential limitations of the Keros classification in younger children and the need for further research.
Area of Science:
- Radiology
- Pediatric Anatomy
- Otolaryngology
Background:
- The olfactory fossa depth is crucial for sinonasal surgery safety.
- The Keros classification is widely used but its applicability in pediatric populations requires further investigation.
- Normative data for olfactory fossa depth in children is limited.
Purpose of the Study:
- To describe the distribution of olfactory fossa depth using the Keros classification in a pediatric cohort.
- To establish normative data for the pediatric population to potentially reduce surgical complications.
- To assess age-related variations in olfactory fossa depth and Keros classification.
Main Methods:
- Retrospective analysis of 390 pediatric patients' paranasal sinus CT scans.
- Patients were stratified into three age groups: 1-6, 6-12, and 12-18 years.
- Olfactory fossa depth was measured and classified according to Keros criteria; asymmetry was also evaluated.
Main Results:
- Olfactory fossa distribution: 24.7% Keros I, 65.9% Keros II, 9.4% Keros III.
- Keros I prevalence was higher in the 1-6 age group, while Keros II was more common in older groups.
- Keros III prevalence increased with age, and olfactory fossa asymmetry was observed in 7.4% of patients.
Conclusions:
- A high Keros I rate and low Keros III rate were noted in children aged 1-6.
- The Keros classification's validity in children under six warrants further examination.
- Larger, diverse population studies are necessary to refine understanding of pediatric olfactory fossa anatomy.
Objective:
With this radio-anatomical study, we aimed to describe the distribution of the depth of the olfactory fossa based on the Keros classification in the pediatric population in our region and to reduce complication rates by providing normative data.
Methods:
This was a retrospective study conducted with computed tomography imaging of the paranasal sinuses of 390 pediatric patients referred over a six-year period in Sakarya and Kocaeli University Faculty of Medicine. Patients were divided into 3 groups as 1-6, 6-12, and 12-18 years old. The depth of the olfactory fossa was measured and classified according to the Keros classification. The incidence of Keros asymmetries was also investigated.
Results:
The distribution of the depth of a total of 780 olfactory fossa according to the Keros classification was 24.7% Keros I, 65.9% Keros II, and 9.4% Keros III. When the groups were evaluated with each other and within each group, it was seen that the prevalence of Keros I type was significantly higher in the first group (p<0.05), and the prevalence of Keros type II was significantly higher in the second and third groups (p<0.05). Apart from this, the number of Keros type III increased in the third group compared to the first two groups and showed a statistically significant difference (p<0.05). Among all patients, asymmetry of the olfactory fossa was detected in 29 patients (7.4%). Although the number of olfactory fossa asymmetry was low in group I, it was not significantly different between the groups (p>0.05).
Conclusion:
In our study, high Keros I rate and low Keros III rate in children aged 1-6 were remarkable. Especially for children under the age of six, questions arise about the validity of the Keros classification. More detailed studies in larger populations, in different ethnicities, and with various age groups are needed.
Level Of Evidence:
Level 3.
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