The eligibility for Nuclear Medicine course are:

• Must have completed BSc with at least 55% marks.
• The student must be from the following fields- Physics, Chemistry, Mathematics, Zoology, Microbiology, Biochemistry, Bioinformatics, Biotechnology, Nuclear Medicine with Physics or Chemistry.

Thus no after MLT you can't go for Nuclear Medicine course.

To know more about Nuclear Medicine visit the link below:

https://www.careers360.com/courses/nuclear-medicine-course

I hope this answer helps. All the very best for your future endeavors!