Table 1.

Time (minutes) taken for each pass using MI and NCC optimization. NCC improves computational speed by a factor of ∼6. Measurements were performed in MATLAB software implemented on a desktop PC (Dell Precision 380; 3.00 GHz CPU; 2 GB RAM). Future work will consider GPU-based implementations for registration speed consistent with clinical requirements.

n	MI optimization	NCC
Pass 1	10.7	2.2
Pass 2	34.0	6.7
Pass 3	154.8	29.1
Pass 4	643.0	115.3