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+--- Thread: any radiologists out there? - boggart (/showthread.php?tid=82257)
any radiologists out there? - boggart - ArchivalUser - 04-05-2006
can someone tell me a website, or if you know can you tell me what is bright and dark on
head:
CT
MRI T1
MRI T2
including pathology changes
0 - ArchivalUser - 04-06-2006
try this ;though sometimes its too detailed(but u can choose which ones u want to see)
the whole brain atlas by keith a. johnson
at:http://www.med.harvard.edu/AANLIB/home.html
sorry i couldn't paste the url directly over here.
gl.
0 - ArchivalUser - 04-06-2006
CT scan is a low intensity xray. MRI has no radiation and is obtained depending on bodys protons. There is an extremely easy way to differentiate between T1 and T2 MRI without even going into the details of white and gray matter. Just look at CSF!!. On T1 sequences CSF appears hypointense( Dark). On T2 Sequences CSF will be appearing ( Hyperintense) Bright. Isn't it Easy???
On CT scan, CSF will be appearing dark, but you will see Cranium bone hyperintense.
As far as Pathology is concerned. If the pathology contains fluid, like Cyst or Hemorrhage, it will appear bright on T2 and dark on T1. If pathology is a growth, it will show as hypointense area. Then they use other sequences like diffusion imaging ( For Stroke) , Flair ( For MS) or inject Gadolinium to differentiate different types of tumors or metastasis.
Talha