Slide 88: What is the light-colored structure in the center of the embryo? Slide 98: What is the triangular shape in the center - the heart or another organ? Slides 108 and 112: Very distorted - Is there a problem with the MRI or is it the contrast of the computer screen? These are just a few questions we would like answered by Beckman. Besides the distortion on two of the slides, the images show a well-developing chic. We can already observe a distinct head and body.

Carl:
The light colored spot at E5 (88 and 98) is the remains of the latebra. It is located in the yolk, which is now flattened and appears triangular on this view (point to the left) The appearance differs in the two images due to a change of imaging technique from T2_contrast to T1_contrast.

Frame 108 appears to have been a double or triple exposure due to simultaneous requests from more than one workstation. Please be patient and wait your turn.

Frame 112 is very "grainy" or snowy because the slice is too thin (1mm) and the field of view too small (45mm). This makes the individual "pixels" too small to give any detectable MRI signal.

The problems with 108 and 112 are discussed in the "Guide to getting the most out of MRI".

Anna, Dasha, Yvone, Rachel
1) The embryo is starting to show more characteristics of a chicken. The images are becoming more recognizable. The t2 contrast is not of much use right now because of the large amounts of liquid in the egg. We have a couple of questions: 1) How do you know on Day 5 images what is the beak and what is the eye or wing?

Carl:
The eyes are distinctive - large and round. In some views they have a well-defined boundary, too. The other features take a bit of guesswork with the limited data we have here. A more careful (and much more time-consuming) research project would acquire many thin slices with signal averaging to improve the image quality. These could then be reconstructed to give views from many different directions, so that a clear understanding of the relationship of the various parts could be obtained.

2) MRI image #99 What are the bright and dark sections?

Carl:
From bottom to top: albumen compartment 1 (dark), yolk (triangular, light), albumen compartment 2 (also light), amniotic sac and chick (bright spot). The streaks and smears are due to movement of the chick during the "exposure" (about 8 seconds for this frame). Notice the difference between this artifact and the ones on the Day 8 News page.

David, Ted, and Fernanda
On the picture of mri.00107, at the bottom of the the picture, we saw a structure that looks like a wing of the chick.

Carl:
This slice is located at the BOTTOM of the yolk. Check the detailed parameters (slice offset, mm is zero, placing the slice at level 4-5 in a front view (like frame 99). The chick is at the top of the shell, near +20mm. The curved structure at F2-F3 is probably a blood vessel, bringing nutrients to the chick from the yolk.