Hasan AYDIN, Egemen ÇİFTÇİ, Baki HEKİMOĞLU

Visualization of 4thcranial nerve with mri: Value of balanced fastfield echo and 3d-drive sequences against the T2-TSE and post-contrast t1w sequences

Bu çalışmanın amacı, 4. kranial (Trokhlear) sinirin sister-nal uzanımını görüntülemede en etkili MRG sekansınıbelirlemektir. Balans fast-field eko (b-FFE), T2A 3D Drive,T2A TSE ve Post-kontrast T1A sekanslar uygulandı ve 4. kranial sinirin analizinde en etkin sekansı bulmaya çalıştık. Bu sekanslar kullanılarak, 4.sinir paralizi şikayeti olmayan 100 hasta çalışıldı. Görüntüleme analizi aşağı-daki şekilde sınıflandırıldı; kesin analiz edilen sinir (Skor 2)- kısmi analiz edilen sinir (Skor 1)- tanımlanamayansinir (Skor 0). Post-kontrast T1A serilerde, kısmi ve tam analizedilen sinir saptanamadı. B-FFE sekansında %50 tam, %11 kısmi görüntülendi. T2A drive sekansı kullanıldı-ğında %19u total, %13’ü kısmi görüntülendi. T2A TSE sekansında ise; Sadece %7 tam görüntüleme yapılırken, %22 sinir kısmi görüntülendi. Sonuç olarak, trokhlear sinirin sisternal uzanımını en iyi görüntüleyen sekans b-FFE sekansı bulunmuştur, sinir fasiküllerini %61 başa-rıyla göstermiştir (100 sinir tam-22 sinir kısmi). Trokhlear sinirin sisternal kısmını belirlemede Drive T2A sekansı T2A TSE sekansından üstünbulunmuştur.

4. Kranial sinirin MR görüntülenmesi: Balans Fast-field eko ve 3D-Drive sekanslarının T2-TSE ve Post-kontrast T1 Ağırlıklı sekanslara karşı değeri

The aim of this study is to assess the best effective MRI sequence forthe visualization of the 4thcranial nerve (Trochlear nerve) in its cisternal course. Balanced fast-field echo (B-FFE), 3D-T2W DRIVE Sense, T2W 2D TSE and Post-contrast T1W sequences were all applied and we tried to get the best sequence for the exact assessment of the 4thcranial nerve. 100 patients without the symptoms of trochlear nerve palsy were examined using the above sequences. Imaging analysis is graded as; nerve analysed by certainty (score of 2), nerve analysed partially (score of 1), nerve is not identified (score of 0). Nerves were not visualized exactly and partially in all cases with the post-contrast T1 series. In B-FFE sequence, 50% was exactly seen-11% partially screened. With using the DRIVE T2W sequences; In 19% of cases nerves were properly seen in 13% cases, the nerves were partially visualized. According to T2W TSE sequence; only 7% of the trochlear nerves were properlydepicted, in 22% cases it was partially visualized. As a conclusion, the best sequence for the visualization of the cisternal course of trochlear nerve is B-FFE among others, with 61% success with showing the fascicles (100 nerves exactly, 22 nerves partially). DRIVE T2W sequence was superior than the T2W TSE in assessing the cisternal part of trochlear nerve.

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