Note 45 — Chapter XXXVII · THE ORBIT AND ITS ADNEXA; THE EXTERNAL AUDITORY APPARATUS; THE ACCESSORY SINUSES; THE CRANIAL AND CERVICAL NERVES; THE ORBITAL CONTENTS AND ADNEXA.

Osmic Acid and Other Treatment of Trigeminal Neuralgia.—While it hardly pertains to operative surgery, it may be worth while to say that it seems to me that no case of trifacial neuralgia should be subjected to radical operation until at least two or three remedies have been given a fair trial. One of these is castor oil its use being based upon the theory that such neuralgia is of toxic origin and that a prolonged evacuant treatment should benefit it. This would mean the administration of two or three good-sized doses of castor oil every day for a period of two to three weeks. It is not such a drastic remedy, thus given, as would appear, for after the oil has once thoroughly produced its laxative effect it ceases to distress, but serves as a very effective eliminant. The second remedy is gelsemium, the best preparation being the tincture of the green root. It seems to exercise a selective affinity for the trifacial nerve. It should be given in large doses, pushed to the physiological limit, i. e., until the patient begins to see everything in yellow colors. Its effect on the heart must also be guarded. Fifteen drops of the green tincture given every two hours, and for a few days, will usually suffice to thoroughly test its efficacy.

Osmic acid is used only for intraneural injection, its efficiency now being under trial. Ten to twelve drops of a 2 per cent., freshly prepared aqueous solution are directly injected into the nerve trunk after its exposure. Murphy has been its particular advocate, and has reported relief of pain in a number of cases thus treated. It seems to depend for its effect upon two factors—the destruction of nerve filaments and their substitution by connective tissue. All the nerve branches that can be exposed should be injected; the palatine and lingual through the mouth; the intra-orbital and supra-orbital by incisions upon the face; orbicular-branches, as well, should be injected, if possible. Most of those who have used it advise also to inject a few drops into the foramina of exit, around the trunks, which are thus infiltrated with the solution. The procedure is painful and usually requires a general anesthetic, but it seems to be free from danger. While the treatment has been successful in some cases it has been equally disappointing in others, and the method will scarcely supplant the more radical method of ganglion exsection.