Does normal substantia nigra echogenicity make a difference in Parkinson’s disease diagnosis? A real clinical practice follow-up study

1. Alonso-Canovas, A.
2. Lopez-Sendon Moreno, J.L.
3. Buisan, J.
4. Sainz de la Maza, S.
5. Costa-Frossard, L.
6. Garcia-Ribas, G.
7. de Felipe-Mimbrera, A.
8. Matute-Lozano, M.C.
9. Zarza Sanz, B.
10. Toledano Delgado, R.
11. Corral, I.
12. Masjuan, J.
13. Martinez-Castrillo, J.C.