How does a midsagittal and parasagittal section (cut) differ?

Midsagittal is a verticals cut cut down the exact center of the line that separates the left half and from right half.
Parasagittal is a verticals cut that is off the center line of that separates the left of the specimens from the right in unequal portions

Blood transfusions were rarely done and often fatal; they were outlawed until the nineteenth century.