Evaluation of interpeduncular angle values according to age and gender by magnetic resonance imaging

Year 2025, Volume: 16 Issue: 2, 386 - 393, 30.06.2025

Nazire Kılıç Şafak , Hüseyin Erdem , Yusuf Kemal Arslan , Sibel Tepecik , Zekiye Karaca Bozdağ , Danış Aygün , Neslihan Boyan , Özkan Oğuz

https://doi.org/10.18663/tjcl.1718763

Abstract

Aim: This study aimed to establish normative, age- and sex-stratified reference values for the interpeduncular angle (IPA), pontomesencephalic angle (PMA), and pontomedullary angle using magnetic resonance imaging (MRI) in a healthy adult population.
Material and Methods: This retrospective study included 290 healthy adult patients (124 males, 166 females; mean age: 43.1 ± 16.7 years) who underwent brain MRI between January 2018 and December 2020. IPA, PMA, and pontomedullary angles were measured on standardized axial and mid-sagittal T1-weighted spin-echo MRI sequences. The classification was as follows: 18–24 years (young adults), 25–33 years (adults), 34–48 years (early middle-aged), 49–64 years (middle-aged), ≥65 years (elderly).
Results: The mean IPA was 75.5° ± 10.2, PMA was 57.0° ± 10.2, and pontomedullary angle was 133.8° ± 10.6. No significant differences in any angular measurements were observed between male and female (p > 0.05). However, a significant increase in IPA values was observed with advancing age (p < 0.001), particularly in middle-aged and elderly groups. IPA showed a moderate positive correlation with age (r = 0.372; p < 0.001), while PMA and pontomedullary angle showed no significant correlation with age. No significant correlations were found among the three angular parameters.
Conclusion: IPA values increase significantly with age, whereas PMA and pontomedullary angles remain relatively stable throughout adulthood. These findings provide normative, age- and sex-stratified reference data for brainstem angular measurements, which may enhance their utility in clinical diagnostics, especially in conditions such as spontaneous intracranial hypotension and neurodegenerative syndromes.

Keywords

interpeduncular angle , pontomesencephalic angle , pontomedullary angle , magnetic resonance imaging , brainstem morphology , normative data

Ethical Statement

The study was performed in accordance with the Declaration of Helsinki, and was approved by the Cukurova University Non-Interventional Clinical Research Ethics Committee (Date: 05.11.2021, Decision No: 2021/116-60).

Manyetik Rezonans Görüntüleme ile Yaşa ve Cinsiyete Göre İnterpedünküler Açı Değerlerinin Değerlendirilmesi

Abstract

Bu çalışma, sağlıklı yetişkin bir popülasyonda manyetik rezonans görüntüleme (MRI) kullanarak interpedünküler açı (IPA), pontomesensefalik açı (PMA) ve pontomedüller açı için normatif, yaşa ve cinsiyete göre tabakalandırılmış referans değerleri belirlemeyi amaçlamaktadır.
Gereç ve Yöntemler: Bu retrospektif çalışmaya Ocak 2018 ile Aralık 2020 arasında beyin MRI'ı çekilen 290 sağlıklı yetişkin hasta (124 erkek, 166 kadın; ortalama yaş: 43,1 ± 16,7 yıl) dahil edildi. IPA, PMA ve pontomedüller açılar, standartlaştırılmış aksiyel ve orta sagital T1 ağırlıklı spin-eko MRI dizilerinde ölçüldü. Sınıflandırma şu şekildeydi: 18-24 yaş (genç yetişkinler), 25-33 yaş (yetişkinler), 34-48 yaş (erken orta yaşlı), 49-64 yaş (orta yaşlı), ≥65 yaş (yaşlı).
Sonuçlar: Ortalama IPA 75,5° ± 10,2, PMA 57,0° ± 10,2 ve pontomedüller açı 133,8° ± 10,6 idi. Erkek ve kadınlar arasında herhangi bir açısal ölçümde anlamlı bir fark gözlenmedi (p > 0,05). Ancak, özellikle orta yaşlı ve yaşlı gruplarında, ilerleyen yaşla birlikte IPA değerlerinde anlamlı bir artış gözlendi (p < 0,001). IPA yaşla orta düzeyde pozitif bir korelasyon gösterdi (r = 0,372; p < 0,001), PMA ve pontomedüller açı ise yaşla anlamlı bir korelasyon göstermedi. Üç açısal parametre arasında anlamlı bir korelasyon bulunamadı.
Sonuç: IPA değerleri yaşla birlikte önemli ölçüde artarken, PMA ve pontomedüller açılar yetişkinlik boyunca nispeten sabit kaldı. Bu bulgular, beyin sapı açısal ölçümleri için normatif, yaşa ve cinsiyete göre sınıflandırılmış referans verileri sağlar ve bu da klinik tanılamada, özellikle spontan intrakraniyal hipotansiyon ve nörodejeneratif sendromlar gibi durumlarda, bunların kullanımını artırabilir.

Keywords

interpedinküler açı , pontomesensefalik açı , pontomedüller açı , manyetik rezonans görüntüleme , beyin sapı morfolojisi , normatif veriler

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