Remeshing segmented model

Is it possible to remesh the surface of the segmented model specifying the element edge size (maybe using surface toolbox)?

There are a number of tools available for this. We need to know a bit more to be able to give advice on which approaches could work for you.

What is your application (3D printing, mesh editing, FEM, …)?

What would you like to achieve by remeshing (have uniform/adaptive element size, increase or decrease the number of elements, …)?

Yes actually I need it for FEA and a uniform mesh should work.
Do you have any suggestions?
Thank you.

You can use SegmentMesher extension to generate a volumetric mesh directly from an image segmentation. I would recommend to use Cleaver2 backend, as it is much more reliable than tetgen and Cleaver2 has a free license (tetgen is commercial/GPL). You have several options for controlling mesh element size - it can be enforced to be strictly uniform size or adaptive (so that you can cut down on computation time and make simulation of large deformations more robust).