What is Horos?
Horos - a free, open medical image viewer. The goal of the Horos Project is to develop a fully functional, 64-bit DICOM viewer for OS X based on OsiriX
Comments and Reviews
Said about Horos as an alternative
It's a fork of OsiriX v5.9
Osirix-based software. Free. Open source. Constantly updated
Nearly identical without the increasingly more onerous update nags.