Tinnituslu hastalarda 3 boyutlu T2 ağırlıklı manyetik rezonans görüntüleme ile serebelopontin kenardaki vasküler değişikliklerin değerlendirilmesi

Abstract

Amaç: Serebelopontin köşe (CPA) vasküler ve nöral yapıların anatomik etkileşimleri işitsel-vestibüler semptomlarla ilişkili olduğu düşünülmektedir. Manyetik rezonans görüntüleme, bu karmaşık anatomik bölgeyi değerlendirmek için tercih edilen bir yöntem haline gelmiştir. Bu çalışmada, 3-boyutlu T2 ağırlıklı MRI ile tinnitus hastalarda CPA’da vasküler loop varyasyon ilişkisini değerlendirmeyi amaçladık.

Materyal ve Metod: Bu çalışmada, açıklanamayan tinnitus olan ve kulak MRI tetkiki yapılan 149 hasta yer almıştır. Hastaların tinnitusu olan kulakları çalışma grubunu, şikâyet olmayan kulakları kontrol grubunu oluşturdu. Çift taraflı tinnitusu olanlar iki taraf ayrı ayrı olarak çalışma grubuna dâhil edildi. MRI taramaları, CPA’da vasküler varyasyon varlığına ilişkin olarak değerlendirildi.

Bulgular: Sol tarafta tinnitusu olan hastalarda Tip 1 (CPA düzeyinde) (p=0.001) ve Tip A (vestibüloklear ve/veya fasial ile temas) (p<0.001) vasküler loop anlamlı derecede yüksekti. Sağ tarafta tinnitusu olan hastalarda, sadece Tip A vasküler loop anlamlı derecede yüksekti (p=0.005). Çift taraflı tinnituslu hastalar için sağ kulakta Tip 2 vasküler loop (internal akustik kanalı proksimal [IAC]) (p=0.035) ve sol kulakta Tip A vasküler loop(p<0.001) anlamlı derecede yüksekti.

Sonuç: Bu çalışma, 3D T2W MRI kullanılarak tinnitus etyolojisini araştıran en büyük ölçekli çalışmadır. CPA ve IAC’deki vasküler loop sıklığı öncelikle tanı tekniğine bağlıdır. Bulgularımız, vasküler varyasyon nedenlerin yüksek çözünürlüklü görüntüleme yöntemleri kullanılarak daha net gösterilebileceğini gösterdi. Buna göre, tedavi seçenekleri etiyolojinin aydınlatılmasıyla daha iyi belirlenebilir.

Keywords

• Vasküler loop,serebelopontin köşe,internal akustik kanal,tinnitus,manyetik rezonans görüntüleme

Evaluation of vascular variations at cerebellopontine angle by 3-dimensional T2-weighted magnetic resonance imaging in patients with tinnitus

Abstract

Objective: Anatomical interactions of vascular and neural structures at cerebellopontine angle (CPA) are considered related to auditory-vestibular symptoms. Magnetic resonance imaging (MRI) has become the preferred method to visualize this complex anatomical region. This study aimed to assess the relation of vascular loops at CPA with clinical symptoms in patients with tinnitus using 3-dimensional (3D) T2-weighted (T2W) MRI.

Materials and Methods: The study included 476 patients, grouped as those with and without tinnitus, undergoing MRI for various clinical auditory symptoms. MRI scans were assessed regarding the presence of vascular abnormalities at CPA.

Results: For the patients with tinnitus on the left side, the frequencies of Type 1 vascular loop (at the CPA level) (p=0.001) and Type A vascular loop (contact with the vestibulocochlear and facial nerves) (p<0.001) vascular loops were significantly higher. For the patients with tinnitus on the right side, only the frequency of Type A vascular loop was significantly higher (p=0.005). For the patients with bilateral tinnitus, Type 2 vascular loop (proximal to the internal auditory canal [IAC]) on the right side (p=0.035) and Type A vascular loop on the left side (p<0.001) were significantly higher.

Conclusion: This study is the largest scale study investigating the tinnitus etiology using 3D T2W MRI. The frequency of vascular loops at the CPA and IAC primarily depends on the diagnostic technique. Our results indicated that vascular causes could be shown more clearly with the use of high-resolution imaging methods. Accordingly, treatment options can be better determined by the clarification of etiology.

Keywords

• Vascular loop,cerebellopontine angle,internal acoustic canal,tinnitus,magnetic resonance imaging

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