Yedinci Servikal Vertebra'ya Ait Bilgisayarlı Tomografi Görüntülerinden Elde Edilen Parametrelerle Geometrik Morfometri Kullanılarak Cinsiyet Tahmini

Öz

Amaç: Vertebraların dayanıklılığı, adli durumlarda veya doğal afetlerde bulunma olasılıklarını artırır. Bu yapılar üzerinden de kimlik tayini işlemleri kolaylaştırılabilir. Kurulan bu hipotez ile yola çıkılan bu çalışmada amaç, 7. servikal vertebra üzerinde belirlenen noktalara geometrik morfometri yöntemi kullanılarak yüksek doğrulukta ve güvenilirlikte cinsiyet tayininin mümkün olup olmadığını ortaya koymaktır. Materyal ve metod: Çalışma 18-65 yaş aralığındaki 300 bireye ait bilgisayarlı tomografi görüntüleri kullanılarak gerçekleştirildi. Görüntüler üç boyutlu hale getirilerek üst üste çakıştırma işlemi uygulandı. Daha sonra gerçek büyütmedeki görüntüler TPS formatına çevrilerek 30 landmark eklendi. Oluşan bu ham koordinatlara Generalized Procrusters Analysis (GPA) analizi uygulanıp ağırlık merkezi etrafında koordinatlar yeniden konumlandırıldı. Yeniden konumlandırılan bu verilere de Principal Component Analysis uygulanıp boyutsallık azaltıldı. Boyutsallığı azaltılan görüntülere de Lineer diskriminant analizi (LDA) uygulanıp cinsiyet tahmini doğruluk oranı elde edildi. Bulgular: Çalışma sonucunda ağırlık merkezi etrafında toplanan koordinatların %63,674’ünün ilk 6 principal component tarafından açıklanabileceği bulundu. Yeni koordinatlara uygulanan LDA analizi ile de %83,33 cinsiyet tahmin oranı elde edildi. Sonuç: Çalışma sonucunda 7. servikal vertebra üzerinde belirlenen noktalara geometrik morfometri yöntemi uygulanarak cinsiyet tahmini açısından yüksek bir doğruluk oranı elde edildi.

Anahtar Kelimeler

• Vertebra prominens
• Geometrik morfometri
• Bilgisayarlı tomografi
• Cinsiyet tahmini

Sex Prediction Using Geometric Morphometry with Parameters Obtained From Computed Tomography Images of the Seventh Cervical Vertebra

Öz

Background: The durability of vertebrae increases their likelihood of being discovered in forensic contexts or natural disasters. Identification procedures can also be facilitated through these structures. The aim of this study, based on this hypothesis, is to determine whether it is possible to identify gender with high accuracy and reliability using geometric morphometry on specific points identified on the 7th cervical vertebra. Materials and Methods: The study was conducted using computed tomography images from 300 individuals aged 18-65. The images were converted into three dimensions and superimposed. The images at actual magnification were then converted to TPS format and 30 landmarks were added. Generalized Procrustes Analysis was applied to these raw coordinates, and the coordinates were repositioned around the center of gravity. Principal Component Analysis was then applied to these repositioned data to reduce dimensionality. Linear discriminant analysis (LDA) was applied to the reduced-dimensionality images to obtain the gender prediction accuracy rate. Results: The study found that 63.674% of the coordinates clustered around the center of gravity could be explained by the first 6 principal components. LDA analysis applied to the new coordinates yielded an 83.33% gender prediction rate. Conclusions: The study achieved a high accuracy rate for gender prediction by applying geometric morphometry to points identified on the 7th cervical vertebra.

Anahtar Kelimeler

• Vertebra prominens
• Geometric morphometry
• Computed tomography
• Sex determination

Kaynakça

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