Can parkinson's be detected by a neck and spinal mri?

Not at this time: A far better test is a PET scan with an appropriate chemical tag for dopamine transporter function.

DAT scan: DAT scan... a nuclear imaging test can be helpful for evaluation of Parkinson's disease.

Not usually: With the exception of associative findings on MRI for particular syndromes, it isn't the best test for Parkinson Disease.