Commentary

The authors have described an unusual presentation of an orbital and optic sheath tumor. The statement that there is considerable controversy concerning the outcome of treatment for these tumors is correct. Whether anything should be done for most patients with these tumors as long as they remain asymptomatic is still debated.

In our extensive experience with these tumors, my colleagues and I at Johns Hopkins developed a paradigm for management that we think is effective. We do not recommend treatment for the typical optic sheath tumor (usually a meningioma) located only within the optic canal until progressive visual loss is obvious. We then use focused or fractionated radiation. If visual loss continues, decompression of the optic canal and opening the optic sheath may prolong useful vision. If visual loss is rapid, decompression may be performed first.

When hyperostosis involves the orbital walls and sphenoid bone and is associated with proptosis, visual loss, or both, we recommend surgery once symptoms are serious enough to warrant treatment. In this case, the sphenoid bone and anterior clinoid are drilled away extradurally and the optic nerve is decompressed intradurally without attempting to remove the tumor radically. The procedure usually relieves protrusion of the eye and alleviates visual symptoms even when the tumor cannot be removed completely.

Seventy years ago Dandy showed us that small extracanalicular tumors can induce considerable hyperostosis. Treating the hyperostosis by removing the intradural tumor can provide years of cure or palliation. However, if tumor is located internal to the optic sheath, we do not attempt to remove it radically. If radical removal is unfeasible, we believe that the available evidence favors postoperative radiation for these tumors. A minority of our group still believes that radiation should follow objective signs of postoperative tumor growth and not be routine.

The authors' review of these unusual tumors and their treatment reminds us of the unanswered questions that attend the management of these tumors.