Experiments and Results

Two series of three experiments were completed varying only the features used by $\begin{sc}animal\end{sc}$ where the first series was completed for simulated data, and the second series, for real MRI data. In each experiment, 10 MRI volumes were registered to the chosen target volume. The 3 different experiments were defined as follows: (1) $\begin{sc}animal\end{sc}$ in standard non-linear mode, (2) $\begin{sc}animal\end{sc}$ +selected sulci, (3) $\begin{sc}animal\end{sc}$ +all sulci after using selected sulci.

In method 2, the problem of establishing correspondence is addressed by using ten extracted sulci (superior and middle frontal, Sylvian, olfactory and central, on both hemispheres) as features in addition to the blurred MRI intensity volume already used by $\begin{sc}animal\end{sc}$ , The third method is an attempt to improve the second, by adding all sulci automatically extracted by $\begin{sc}seal\end{sc}$ into the registration process after completing the $\begin{sc}animal\end{sc}$ +selected sulci registration. A linear transformation is also presented for comparisons. Figures 2 and 3 summarize the results qualitatively for simulated and real data, respectively. Tables 1 and 2 present quantitative results for the measure described above.

	TABLE 1				TABLE 2

	simulations				real MRI
	lin	$\nabla$	$\nabla+5$	$\nabla+all$	lin	$\nabla$	$\nabla+5$	$\nabla+all$
Central	3.2;1.5	1.2;1.4	0.7;0.3	0.7;0.4	4.7;1.3	4.1;1.4	2.5;1.2	2.5;1.2
Postcentral	4.2;2.3	2.2;2.4	1.3;1.5	1.3;1.5	6.4;1.7	6.1;2.0	5.0;1.7	5.0;1.8
Middle Frontal	3.2;1.0	1.4;1.2	0.7;0.6	0.7;0.6	6.2;3.5	5.4;3.2	4.5;3.1	4.7;3.2
Superior Frontal	3.4;1.9	1.8;2.1	1.6;2.1	1.7;2.1	6.2;3.8	5.6;3.6	4.4;3.9	4.4;4.0
Sylvian	4.0;1.3	3.0;1.2	2.4;0.9	2.4;1.0	5.2;1.6	5.0;1.4	3.6;0.9	3.7;1.0
Olfactory	3.2;4.2	1.7;2.8	1.5;2.9	1.6;2.8	2.1;1.7	1.6;1.9	1.3;1.6	1.4;1.8
average (n=16)	3.4;2.3	2.1;2.1	1.6;1.7	1.5;1.7	5.0;3.2	4.5;3.1	4.0;3.1	4.0;3.1

$\textstyle \parbox{12.2cm}{Quantitative results for simulations and real data. ... ...d right hemispheres for 16 sulci on 10 subjects. All measures in millimeters.}$