Lymphatic capillaries in the meninges of the human optic nerve.
OBJECTIVE
Although many anatomical studies of the orbit and the optic nerve have been performed, lymphatic capillaries in the dura of the human optic nerve have never been reported. This study was performed to determine whether or not lymphatic capillaries are present in the dura of the human optic nerve.


METHODS
This postmortem study was carried out in seven subjects without ocular disease. The subjects were obtained no later than 6 hours after death, following qualified consent for autopsy. The dura of the human optic nerve was studied with light microscopy, scanning electron microscopy, and transmission electron microscopy. In some cases, india ink was injected into the subarachnoid space as a marker.


RESULTS
Lymphatic capillaries in the dura of the human optic nerve were morphologically demonstrated with histological criteria (fenestrated endothelium, lack of a basal membrane, and absence of blood cells in the lumen of the vessels). The highest concentration of lymphatic capillaries was found in the bulbar part of the dura behind the ocular globe. Using light microscopy and transmission electron microscopy, ink was seen within the lumen of the lymphatic capillaries. The dura itself was not stained with the marker.


CONCLUSIONS
The presence of lymphatic capillaries in the dura of the human optic nerve was demonstrated with light microscopy, transmission electron microscopy, and scanning electron microscopy.
Killer
H E
HE
Department of Ophthalmology, Teaching Hospital for the University of Basel and Bern, Switzerland.
Laeng
H R
HR
Groscurth
P
P
D002102:Cadaver; D002244:Carbon; D002555:Cerebrospinal Fluid / Q000378:metabolism; D004396:Coloring Agents; D006801:Humans; D008208:Lymphatic System / Q000033:anatomy & histology* / Q000378:metabolism / Q000648:ultrastructure; D008854:Microscopy, Electron; D008855:Microscopy, Electron, Scanning; D009900:Optic Nerve / Q000033:anatomy & histology* / Q000378:metabolism / Q000648:ultrastructure; D013346:Subarachnoid Space / Q000378:metabolism
D004396:Coloring Agents; C028433:chinese ink; D002244:Carbon