The eye of Vesalius.

In the time of Vesalius, knowledge of ocular anatomy was limited. The first description of the anatomy of the eye comes from Democrites, for whom the eye was surrounded by two 'coats', filled with a homogenous fluid. The optic nerve was hollow and the lens was considered to be a postmortem artefact. Until the 15th century AD, medicine was influenced by the writings of Galenus and the model of the eye he proposed was still considered valid, even after Vesalius. According to the Alexandrian tradition, the lens was considered as the seat of visual perception. Although Vesalius rightly deserves the title of father of modern anatomy, his description of ocular anatomy was rudimentary and often incorrect. He described a musculus retractorius bulbi, which is found only in lower mammals, not in primates. The lens, the role of which as an optical device he recognized correctly, was placed too centrally in the eye. The optic nerve was not correctly placed and, following Galenus, Vesalius described only seven cranial nerves. The Galenian concept of ocular anatomy was to endure until the development of the microscope by Anthony van Leeuwenhoek. Modern ocular anatomy, in fact, can be dated from the works of Zinn.

Verteporfin photodynamic therapy for choroidal neovascularization associated with toxoplasmic retinochoroiditis.

PURPOSE: To evaluate the efficacy and safety of verteporfin photodynamic therapy (V-PDT) for young adults and children with subfoveal choroidal neovascularization (CNV) associated with toxoplasmic retinochoroiditis. METHODS: Patients with subfoveal CNV associated with toxoplasmic retinochoroiditis were treated with V-PDT and prospectively followed up. Before V-PDT and during follow-up, patients underwent visual acuity testing, complete ophthalmic examination including color photography, angiography with fluorescein and/or indocyanine green, and optical coherence tomography. The decision to retreat CNV was based on the criteria used in the Treatment of Age-Related Macular Degeneration with Photodynamic Therapy investigation. RESULTS: Eight patients (5 males and 3 females) were treated at a mean age of 15.3 years (range, 5-31 years). CNV was 100% classic or predominantly classic in all study patients. Mean visual acuity increased from 20/225 (range, 20/400 to 20/50) to 20/123 (range, 20/200 to 20/25) during a mean follow-up period of 25 months (range, 5-49 months). Persistent closure of CNV was achieved in all eight patients (mean number of treatments, 1.75). Vascular anastomosis developed in the treated area in two patients, but there was no additional visual loss. No significant adverse effects of V-PDT were observed. CONCLUSION: V-PDT for subfoveal CNV associated with toxoplasmic retinochoroiditis appears to be effective and safe even in young adults and children. However, a longer follow-up is recommended to confirm our observations.