How important is susceptibility-weighted imaging in mild traumatic brain injury?

BACKGROUND: Mild traumatic brain injury (mTBI) is a public health problem that is recognized as a “silent epidemic” in its late stages due to undiagnosed axonal damage rated 13 and above on the Glasgow Coma Scale (GCS). Injury-related microhemorrhages often cannot be detected on computed tomography (CT) scans and conventional magnetic resonance imaging (MRI). This study aims to investigate whether susceptibility-weighted imaging is feasible in mTBI patients.
METHODS: Fifty-eight patients with GCS scores of 14 and 15 and with symptoms of brief mental fogs, impairment of concentration, memory loss, headache, dizziness, or imbalance after brain injury were examined at the emergency service. A brain CT scan and MRI containing diffusion-weighted and susceptibility-weighted imaging (SWI) sequences were performed on the patients whose symptoms did not seem to alleviate after the sixth hour. Thirteen patients were excluded from this study because of advanced age, diabetes, a history of hypertension or its chronic sequelae, or acute cerebrovascular disease; 45 patients were included in this study.
RESULTS: The patients’ CT results were normal, and no diffusion restrictions were observed. The SWI revealed microhemorrhages in seven patients (15.6%). Five of these patients had hyperintense areas in conventional sequences corresponding to the hemorrhages spotted in the SWI. In three of the five patients, these pockets of hemorrhages were higher in number and size in comparison with conventional in the SWI sequence.
CONCLUSION: Susceptibility-weighted imaging, which can be used to assess the presence and severity of microhemorrhages due to diffuse axonal injury, is recommended for determining the cause of symptoms in patients with mTBI, to continue targeted treatment and prevent complications that may develop.

Hafif travmatik beyin hasarýnda duyarlýlýk aðýrlýklý görüntüleme ne kadar önemli?

AMAÇ: Hafif travmatik beyin hasarý (mTBI), Glascow Koma Skalasý (GCS) 13 ve üzerinde olan, taný alamayan aksonal hasar nedeniyle geç dönemde ‘sessiz epidemik’ olarak adlandýrýlan bir halk saðlýðý sorunudur. Bilgisayarlý tomografi (BT) ve konvansiyonel manyetik rezonans gorüntülemede (MRG) hasara baðlý mikrohemorajiler çoðunlukla görüntülenememektedir. Bu çalýþmada, MRG sekanslarýndan duyarlýlýk aðýrlýklý görüntülemenin (SWI) mTBI olgularýnda uygulanabilir olup olmadýðýnýn araþtýrýlmasý amaçlanmýþtýr.
GEREÇ VE YÖNTEM: Beyin hasarý sonrasý GCS’si 14 ve 15 olan, kýsa süreli bilinç bulanýklýðý, konsantrasyon zorluðu, hafýza kaybý, baþ aðrýsý, baþ dönmesi, dengesizlik gibi semptomlarý bulunan 58 hasta acil serviste deðerlendirildi. Altýncý saatten sonra semptomlarý gerilemeyen hastalara beyin BT ve difüzyon aðýrlýklý ve SWI sekanslarýný içeren MRG çekildi. On üç hasta, ileri yaþ, diyabet, hipertansiyon öyküsü ve kronik sekel deðiþiklikler, akut serebrovasküler hastalýk bulgusu bulunmasý nedeniyle dýþlandý.
BULGULAR: Olgularýn BT bulgularý normaldi, difüzyon aðýrlýklý sekanslarda difüzyon kýsýtlanmasý izlenmedi. Yedi hastada (%15.6) SWI’da mikrohemoraji odaklarý saptandý. Bunlarýn beþinde SWI’daki mikrohemoraji alanlarý konvansiyonel sekanslarda hiperdens odaklar olarak izlendi. Bu olgularýn üçünde ise mikrohemoraji odaklarý sayý ve boyut açýsýndan SWI sekansýnda T2A ve FLAIR’a göre artmýþtý.
TARTIÞMA: Diffüz aksonal hasara baðlý mikrohemoraji varlýðýný ve ciddiyetini deðerlendirebilen SWI, hafif beyin hasarlý (mTBI) hastalarda semptomlarýn nedenini açýklamak, nedene yönelik tedavisini sürdürmek ve geliþebilecek komplikasyonlarý önlemek için tavsiye edilir.