One rather fantastic theory suggests that the Mandylion later turned up in Turin as the shroud. See Ian Wilson, The Shroud of Turin (Garden City, NY: Doubleday, 1978); and the critique of such a theory in Averil Cameron, “The Sceptic and the Shroud,” in Continuity and Change in Sixth-Century Byzantium (London: Variorum Reprints, 1981).