Prevalence of Pterygoid Process Pneumatization, Distribution of Anterior Skull Base Depth, and Their Correlation

Abstract

Aim: Prior to functional endoscopic sinus surgery (FESS), Paranasal Sinus Computed Tomography (PSCT) is routinely performed to assess anatomical structures and variations in detail. Numerous studies have investigated the relationships between anatomical structures in the paranasal region. This study aims to evaluate the impact of pterygoid process pneumatization (PPP) on the depth of the olfactory sulcus and the anterior skull base (ASB) in the Turkish population. Materials and Methods: PSCT images of 460 patients aged 18 years and older were retrospectively analyzed. PPP and ASB depth were evaluated separately for the right and left sides using the Keros classification. The association between PPP and ASB depth, as well as its impact on the Keros classification, was statistically assessed. Results: A total of 460 patients were included in the study, comprising 222 males (48.3%) and 238 females (51.7%), based on PSCT images. According to the Keros classification, a similar distribution was observed between the right and left sides, with Type 2 being the most prevalent (54.1%), followed by Type 1 (28.3%), while Type 3 (17.6%) was the least frequent. PPP was identified in 40.7% of cases on the right side, 42.2% on the left side, and 39.1% bilaterally. Statistical analysis revealed no significant association between PPP and Keros classification. Conclusion: Our study demonstrated that PPP was present in 42.2% of cases on the left side, with Keros Type 2 being the most common classification. No significant correlation was found between PPP and ASB depth, suggesting that PPP does not influence the depth of the anterior skull base.

Keywords

• paranasal sinuses
• anatomic variation
• computed tomography
• skull base

Supporting Institution

The study did not receive funding.

Ethical Statement

Ankara Bilkent City Hospital, TABED-1-25-914/15.01.2025

Pterygoid Process Pnömotizasyonunun Sıklığı, Anterior Kafa Tabanı Derinliğinin Dağılımı ve Birbiriyle Korelasyonu

Abstract

Fonksiyonel endoskopik sinüs cerrahisi öncesinde paranazal sinüsler, Paranazal Sinüs Bilgisayarlı Tomografi (PSBT) ile dikkatli değerlendirilerek anatomik yapılar ve anatomik varvasyonlar dikkatle değerlendirilmektedir. Paranazal bölgedeki anatomik yapıların ilişkisini inceleyen pek çok çalışma bildirilmiştir. Çalışmamızda pterygoid process pnömotizasyonunun olfaktor sulkus ve anterior kafa tabanı derinliğine etkisinin Türk popülasyonunda araştırılması amaçlanmıştır. Gereç ve Yöntemler: 18 yaş üstü 460 hastanın PSBT görüntüleri incelenmiştir. PSBT’de, pterigoid proses pnömatizasyonu ve Keros sınıflaması ile anterior kafa tabanı derinliği, sağ ve sol olarak ayrı ayrı değerlendirilmiştir. Pterigoid proses pnömotizasyonunun anterior kafa tabanı derinliği ve Keros sınıflaması üzerine etkisi değerlendirilmiştir. Tüm sonuçlar istatistiksel olarak değerlendirilmiştir. Bulgular: 222 erkek (% 48,3 ), 238 kadın (% 51,7) toplamda 460 hastanın PSBT görüntüleri değerlendirilmiştir. Keros klasifikasyonuna göre, sağ ve sol taraflar arasında benzer dağılımlar gözlemlenmiş olup, en yaygın %54,1 oranıyla tip 2, bunu %28,3 oranla tip 1 ve en düşük sıklıkta %17,6 oranla tip 3 takip etmiştir. Çalışmamızda, %40,7 sağda, %42,2 solda ve %39,1 bilateral pterygoid process pnömotizasyonu saptandı. Pterygoid process pnömotizasyonunun Keros sınıflaması üzerinde istatistiksel anlamlı bir etkisi olmadığı saptanmıştır. Sonuç: İkinci basamak hastanelerde psikiyatri kliniği için fiziki olarak kapalı hasta servislerinin yaygınlaştırılması, yan dal uzmanı ve özellikle uzman sayısının az olduğu branşlarda hekim sayısının artırılması ile sevk edilen hasta sayılarında azalma olacağı düşünülmektedir.

Keywords

• anatomik varyasyon
• bilgisayarlı tomografi
• paranazal sinüs
• kafa tabanı

Supporting Institution

Rapor edilecek hiçbir destek kaynağı yoktur.

Ethical Statement

Ankara Bilkent Şehir Hastanesi, TABED-1-25-914/15.01.2025

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