Lorenzo LORUSSO¹, Berti G. BOCK², A.F. FRANCHINI² and A. PORRO^3
1Neurology Department, "M. Mellini" Hospital, Chiari, Brescia, Italy.  walton2002 AT libero.it
²History of Medicine, University of Milan, Italy.  antonia.franchini AT unimi.it
³History of Medicine, University of Brescia, Italy.  porroale AT med.unibs.it

Consequence of exposure to intense light and physical properties of sunlight were known since Greeks. Plato and Xenophon warned against direct observation of the sun. Studies concerning those properties and effects were encouraged by introduction of ophthalmoscopes and development of phototherapy. In 20th century Luigi Maggiore (1888-1970) began to apply phototherapy for intraocular neoplasms. In the same time and independently José Morón-Salas and Gerard Meyer-Schwickerath (1920-1992) experimented the use of sunlight for the treatment of internal ocular diseases. Later Meyer-Schwickerath direct his research on intense resource developing a powerful arc lamp that was applied to treat retinal detachment.

Emilio Raverdino (1896-1977) designed a photocoagulator based on xenon lamp, assembled and marketed by Officine Prevost in Milan, a manufacturer of cinematographical apparatuses in which a xenon lamp was usually employed. Almost simultaneously, Meyer-Schwickerath applied a similar apparatus by Carl Zeiss company as a photocoagulator. The apparatuses were similar, but in Raverdino’s model the use of an intra-red filter was optional.

Invention and rapid spread of incandescent lamps banished the electric arc to field not strictly related to lighting, or necessitating a particular intensity of light, often related to spectral features. In cinematography the arch lamp was the best light source. Problems to use the electric arc as a source of energy by Raverdino and Meyer-Schwickerath was satisfactory with ophthalmoiatric colleagues: Carl Zeiss and Officine Prevost were the main European manufacturers of cinematographical apparatus.

Concerning the treatment in neuro-ophthalmology disorders, photocoagulator was applied in corneal and retinal pathology, Eale disease, diabetic retinopathy, von Hippel-Lindau angiomatosis and viral infections (in herpetic cases).

Photodynamic therapy is accepted as a method of care to limit as far as possible any damage to a patient’s neuro-optical structure. Raverdino and Meyer-Schwickerath's studies were important to understand the intrinsic nature of light to the application in the basic and application medicine.

12th Annual Meeting of the International Society for the History of the Neurosciences   (ISHN)
Los Angeles, California, USA, 19-23 June 2007