Morphometry Of The Olfactory Bulb, Tract, Trigon and Sulcus: An Anatomical Study

Abstract

Aim: Most common sites of injury in patients with posttraumatic olfactory dysfunction are the olfactory bulbs and tracts followed by the inferior frontal lobes and volumes of bulb and tract were
smaller in these patients. Also during the frontal lesion resections there is increased injury risk for
olfactory structures in this region. This study aimed to provide direct normal morphometical information regarding dimensions of olfactory bulb, tract, trigon and sulcus.
Materials and Methods: 80 basal surfaces of forty adult cadaveric brains were evaluated. The following parameters were measured using digital caliper: olfactory bulb length and width, olfactory tract height and width, distance between anterior border of the olfactory bulb and posterior
border of the olfactory trigon, the olfactory sulcus depth and the length of olfactory tract.
Results: Means of the distance between anterior border of the olfactory bulb and posterior border of the olfactory trigon and length of olfactory tract were measured as 42.5±8.45 mm and
25.53±7.11 mm, consequently. Also means of olfactory bulb length and width, olfactory tract height and width were 13.22±3.14 mm, 4.87±1.83 mm, 1.97±1.86 mm and 2.87±2.64 mm, consequently. The mean of the olfactory sulcus depth was obtained as 9.91±2.87 mm.
Conclusion: Precise knowledge regarding the normal anatomic features of the olfactory bulb,
tract, trigon and sulcus and their morphometrical relations are important during treatment of
frontotemporal lesions and during pterional approaches. Normal anatomical features and dimensions of the olfactory bulb and tract are also helpful during decision about damage of these structures. 

Keywords

• Olfactory Bulb
• Olfactory Tract
• Olfactory Trigon
• Olfactory Sulcus
• Morphometry

Bulbus Olfactorius, Tractus Olfactorius, Sulcus Olfactorius ve Trigonum Olfactorium Morfometrisi: Anatomik Çalışma

Abstract

Amaç: Travma sonrası koku disfonksiyonu olan hastaların en sık hasar gören yerleri bulbus olfactorius ve gyrus frontalis inferior’a uzanan tractus olfactorius’lardır. Bu hastalarda bulbus ve tractus olfactorius’ların hacim ve boyutları daha küçüktür. Ayrıca frontal kitle rezeksiyonları esnasında olfaktor yapılara zarar verme riski yüksektir. Bu çalışma bulbus olfactorius, tractus olfactorius, sulcus olfactorius ve trigonum olfactorium’un direk normal boyutları hakkında morfometrik ölçümler elde etmeyi amaçlamıştır. Gereç ve Yöntem: Kırk insan beyninin 80 adet lobus frontalis’in bazal yüzeyi incelendi ve değerlendirmeye alındı. Dijital kumpas aracılığı ile bulbus olfactorius’un uzunluk ve genişliği, tractus olfactorius’un genişlik ve kalınlığı, bulbus olfactorius’un ön sınırı ile trigonum olfactorium’un arka sınırı arasındaki mesafe, sulcus olfactorius’un derinliği ve tractus olfactorius’un uzunluğu ölçüldü. Bulgular: Bulbus olfactorius’un ön sınırı ile trigonum olfactorium’un arka sınırı arasındaki mesafe ve tractus olfactorius’un uzunluğunun ortalamaları, sırasıyla 42,5±8,45 mm ve 25,53±7,11 mm olarak bulundu. Bulbus olfactorius’un uzunluk ve genişliği, tractus olfactorius’un genişlik ve kalınlığının ortalamaları da sırasıyla 13,22±3,14 mm, 4,87±1,83 mm, 1,97±1,86 mm ve 2,87±2,64 mm olarak ölçüldü. Sulcus olfactorius’un derinliği de, ortalama 9,91±2,87 mm olarak bulundu. Sonuç: Bulbus olfactorius, tractus olfactorius, sulcus olfactorius ve trigonum olfactorium’un normal anatomik özellikleri ve morfometrik ilişkisi hakkındaki direk elde edilen bilgi frontotemporal lezyon tedavisinde ve pterional yaklaşımlar esnasında önemlidir. Ayrıca bulbus olfactorius ile tractus olfactorius’un normal anatomik özellikleri ve boyutları bu yapıların normal olup olmadıklarına karar verirken de yardımcıdır.

Keywords

• Bulbus Olfactorius
• Tractus Olfactorius
• Trigonum Olfactorium
• Sulcus Olfactorius
• Morphometri

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