Primary progressive multiple sclerosis diagnostic criteria: a reappraisal

Montalban, X; Sastre Garriga, J; Filippi, Massimo; Khaleeli, Z; Tellez, N; Vellinga, Mm; Tur, C; Brochet, B; Barkhof, F; Rovaris, M; Miller, Dh; Polman, Ch; Rovira, A; Thompson, Aj