BEYİN TÜMÖRLERİNİN 3T MANYETİK ALANDA İN VİVO FOSFOR MANYETİK REZONANS SPEKTROSKOPİK GÖRÜNTÜLEME PİKLERİNİN Z-SKORLARINA DAYALI İNCELENMESİ

Abstract

Amaç: Fosfor manyetik rezonans spektroskopik görüntüleme (³¹P-MRSG) beyin tümörlerinin enerji metabolizması hakkında non-invazif olarak bilgi sağlar. Bu çalışmanın amacı, beyin tümörlerinin 3T manyetik alanda in vivo fosfor manyetik rezonans spektroskopik görüntülenmeleri sonucunda elde edilen piklerin oranlarına bağlı z-skorları tanımlamak ve değerlendirmektir.

Gereç ve Yöntem: On üç beyin tümörü teşhisi konmuş hastanın ve beş sağlıklı gönüllünün beyin ³¹P-MRSG verileri retrospektif olarak incelendi. Hastalarda tümörlü ve normal görünen bölgelerden, ve sağlıklı gönüllülerden elde edilmiş olan ³¹P-MRSG pik değerlerine bağlı z-skorları tanımlandı. Pik oranlarının ve z-skorlarının bu üç grup arasındaki farklılıkları karşılaştırıldı.

Bulgular: Hastaların ortalama yaşı 53.2±12.4, sağlıklı gönüllülerin ortalama yaşı ise, 34.4±11.6 yıl olarak saptandı. Retrospektif planlanan bu çalışmada, beyin tümörlü hastalarda tümörlü bölgelerde, normal görünen bölgelerine ve sağlıklı gönüllülerin beyin bölgelerine göre istatistiksel olarak anlamlı daha yüksek GPC/PCr, GPE/PCr, Pi/PCr, PC/PCr, PE/PCr, γATP/PCr, αATP/PCr, βATP/PCr, (GPE+PE)/PCr, ve (GPC+PC)/PCr pik oranları tespit edildi. Beyin tümörlü dokuda, GPC/PCr, PC/PCr, PE/PCr, β-ATP/PCr, ve (GPC+PC)/PCr pik oranlarına bağlı hesaplanan z-skorları normal görünen dokudan istatistiksel olarak anlamlı yüksek bulundu.

Sonuç: Bu çalışmanın sonucunda, beyin tümörlerinin lokalizasyonu, biyopsi hedefi tanımlanması ve tedavi sonrası takiplerinde, standart ve objektif bir ölçüm olarak kullanılabilecek ³¹P-MRSG pik oranlarına bağlı z-skorları tanımlanmıştır.

Anahtar kelimeler: fosfor manyetik rezonans spektroskopik görüntüleme; beyin tümörü; z-skoru; 3 Tesla

Keywords

• fosfor manyetik rezonans spektroskopik görüntüleme, beyin tümörü, z-skoru, 3 Tesla

Z-SCORE BASED INVESTIGATION OF IN VIVO PHOSPHORUS MAGNETIC RESONANCE SPECTROSCOPIC IMAGING PEAKS OF BRAIN TUMORS AT 3T

Abstract

Objective: Phosphorus magnetic resonance spectroscopic imaging (³¹P-MRSI) provides information about the energy metabolism of brain tumors noninvasively. The aim of this study is to define and assess the z-scores of the in vivo phosphorus magnetic resonance spectroscopic imaging peak ratios of brain tumors at 3T.

Materials and Methods: ³¹P-MRSI data of thirteen brain tumor patients and five healthy volunteers were retrospectively analyzed. z-scores were defined based on the ³¹P-MRSI peak ratios obtained from the tumor and normal appearing regions of the brain tumor patients and the healthy volunteers. The peak ratios and the z-scores were compared between these three groups.

Results: The mean age was 53.2±12.4 years in brain tumor patients, and 34.4±11.6 years in volunteers. In this retrospective study, statistically significantly higher GPC/PCr, GPE/PCr, Pi/PCr, PC/PCr, PE/PCr, γATP/PCr, αATP/PCr, βATP/PCr, (GPE+PE)/PCr, and (GPC+PC)/PCr peak ratios were observed in tumor regions than both normal appearing regions of patients and healthy volunteers. The z-scores calculated based on GPC/PCr, PC/PCr, PE/PCr, β-ATP/PCr, and (GPC+PC)/PCr peak ratios were statistically significantly higher in brain tumor regions than normal appearing regions.

Conclusion: As a result of this study, z-scores based on ³¹P-MRSI peak ratios were defined that might be used as a standardised and objective measure in brain tumor localization, biopsy target definition and followup after treatment.

Key words: phoshporus magnetic resonance spectroscopic imaging, brain tumor, z-score, 3 Tesla,

Keywords

• phoshporus magnetic resonance spectroscopic imaging,brain tumor,z-score,3 Tesla

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