a$)$ Using the T $1,$ T$2,$ and proton density values given below, at what TR do we

achieve a maximum contrast between white matter and gray matter on a T $1-$wieghted

image? $($b$)$ At what TR are the signal intensities of white and grey matter equal? $($c$)$

At what TE do we achieve a maximum contrast on a T$2-$weighted image? For the T$2-$

weighted image assume a TR where the signal intensities of white and grey matter

are equal. You can determine the answer for $($b$)$ using Microsoft EXCEL, but $($a$)$ and

$($c$)$ must be solved for algebraically.

T$1,$ T$2,$ and Proton Density of Brain Tissues

T$1($msec$)$ T$2($msec$)$ Proton Density

White Matter $510670\mathrm{.}61$

Gray Matter $760770\mathrm{.}691)($a$)$ Using the $\backslash ($ T$\_\{1\},$ T$\_\{2\}\backslash ),$ and proton density values given below, at what TR do we achieve a maximum contrast between white matter and gray matter on a T$,-$wieghted image? $($b$)$ At what TR are the signal intensities of white and grey matter equal? $($c$)$ At what TE do we achieve a maximum contrast on a $\backslash (\backslash$mathrm$\{$T$\}\_\{2\}\backslash )-$weighted image? For the T$2$weighted image assume a TR where the signal intensities of white and grey matter are equal. You can determine the answer for $($b$)$ using Microsoft EXCEL, but $($a$)$ and $($c$)$ must be solved for algebraically.

$\backslash$begin$\{$tabular$\}\{|$c$|$c$|$c$|$c$|\}$

$\backslash$hline $\backslash$multicolumn$\{4\}\{|$c$|\}\{$ T$1,$ T$2,$ and Proton Density of Brain Tissues $\}\backslash \backslash$

$\backslash$hline & T$1($msec$)$ & T$2($msec$)$ & Proton Density $\backslash \backslash$

$\backslash$hline White Matter & $510$ & $67$ & $0\mathrm{.}61\backslash \backslash$

$\backslash$hline Gray Matter & $760$ & $77$ & $0\mathrm{.}69\backslash \backslash$

$\backslash$hline

$\backslash$end$\{$tabular$\}$