Marie Biré, 41, of Lussaud in the Vendée, had gone blind in February 1906 from bilateral optic-nerve atrophy — a degenerative condition then (and now) considered irreversible. Her optic discs had been examined repeatedly by ophthalmologists at Nantes and were documented as pale, atrophic, and incapable of transmitting visual signals. She was brought to Lourdes in August 1908 on a stretcher.
On the afternoon of August 5, as the Blessed Sacrament procession passed her stretcher on the esplanade, she suddenly cried out that she could see. The vision was perfect. She walked to the Bureau des Constatations Médicales. The on-duty ophthalmologists examined her optic discs — and found them still atrophic and degenerated. She could see, yet by the laws of physiology she should not have been able to. The discs gradually regenerated over the following weeks. The cure was formally recognised by the Bishop of Luçon in November 1908.