View Full Version : Markers and medical imaging (CT).

10-13-1997, 11:21 PM
Dear Biomch-L Readers,

We are planning to start new experiments involving visualization of
external markers on CT-Scan images. We'd like to determine the centroid
of these markers from the images (with the highest accuracy of course!).

I'd like to know your opinion and/or experience about the following:

1) According to you, what is the best ratio between the size of the marker
and the thickness of the CT slice ?

A ratio 1:1 should give good resul IF each marker is included EXACTLY in one slice. Better,
the marker should a)- be cube-shaped, b)- have the size of a voxel and c-) be entirely
included in a particular voxel.
Unfortunatly, this is theoretical and practically (we think, maybe we're wrong!?)
difficult to implement ...

So, what is the best marker size? We haven't found anything specific about that particular
topic in the litterature.

2) Are tantalum markers still the best for X-rays experiment ?
If not, what is the best matter?

3) Does somebody know the name of a company selling products made of tantalum (balls, plates)?

Thank you VERY much in advance !!!

I'll post a summary of the answers.


Serge VAN SINT JAN, Ph.D. | phone: + 32 2 555 63 25 (office)
Dept. of Anatomy (CP 619) | + 32 2 555 63 76 (secretary)
University of Brussels | fax: + 32 2 555 63 78
808 Lennik Street | email: sintjans@ulb.ac.be
1070 Brussels - Belgium | WWW: http://homepages.ulb.ac.be/~sintjans