Figure 3.

Tc-99m TRODAT-1 SPECT image of control (A) and patients belonging to different H and Y stages (B-F). B: stage 1, patient had history of rest tremors in left upper limb since 2 years; image shows reduced uptake in right putamen; C: stage 2, patient presented with difficulty in writing, rest tremor in bilateral upper limb, more on right side, image shows reduced ^99mTc-TRODAT-1 uptake in bilateral putamen (L<R) with preserved uptake in bilateral caudate nuclei; D: stage 3, patient had bilateral rest tremor and difficulty in walking; image shows no significant uptake in bilateral putamen, reduced uptake in right caudate nucleus. Uptake in left caudate nucleus is preserved; E: stage 4, patient presented with slowness of movements, rest tremors, difficulty in walking without support; image shows no significant uptake in bilateral putamen and reduced uptake in left caudate nucleus. Uptake in right caudate nucleus also appears reduced; F: stage 5, patient had rest tremors, was wheel chair bound, rigidity in all 4 limbs (R>L); image shows no significant uptake in bilateral putamen and right caudate nucleus, and reduced uptake in left caudate nucleus