Grunert followed the method of Gerota in injecting a solution of Prussian blue into the skin of the lid. This fills first the superficial network of the lymph spaces and capillaries which pervades the subcutaneous fatty tissue between the skin and the orbicularis muscle. Among the muscle bundles numerous canals pass to a second network which lies on the tarsus. The exit channels have deep and superficial origins, but both end jointly in the same lymph gland.
Reference: Grunert. On the lymph passages of the lids. Arch Ophthalmol. 1902;31:43.
The Lymph Passages of the Lids. Arch Ophthalmol. 2003;121(8):1203. doi:10.1001/archopht.121.8.1203