[Retinal rosettes and their relation to the vitreoretinal barrier in the chronobiologic model]

Chronobiological experiments were carried out on animals to investigate the peristatic development of retinal rosettes in the course of a day. Every 3 h one single dose of four different concentrations of cyclophosphamide (CP) was applied subcutaneously under defined conditions in young mice of the Agnes Bluhm strain, Halle. A series of 1,396 eyes was studied to determine which retinal malformations were present in the fine tissue. The authors found daily variations in all rosettes in the inner retinal layers, which are of interest here. However, there was no hint of any circadian pattern. The incidence in rosettes in the inner retinal layers increased in correspondence with a decrease in CP concentration. Disturbances of the vitreoretinal limiting membrane were not only detected in rosettes placed in the ganglion and nerve fibre layers and in epiretinal positions, but also in very large rosettes penetrating all retinal layers. In 7 eyes a special form of rosettes was found: a rosette scattered in the vitreous body like a floater. The authors emphasize the importance the localization of rosettes has for clinical practice.