Sympathectomy for glaucoma: Its rise and fall (1898-1910).

The influence of the sympathetic nervous system upon intraocular pressure (IOP) has been a subject of great interest since 1727, when the first experimental ocular sympathetic paralysis was produced in dogs. By the middle of the 19th century, it was known that excision of the superior cervical sympathetic ganglion lowered, and that electrical stimulation of the sympathetic nerve trunk raised IOP in various animals. From these observations, it was thought that excision of this ganglion could replace or supplement the available operations for glaucoma of which iridectomy was the most popular. Iridectomy was acknowledged to be of great value in acute and subacute glaucoma, but less useful in chronic glaucoma. Iridectomy, however, was associated with major surgical complications and long-term failure, so that there was considerable appeal of an extraocular operation that avoided the risks of intraocular surgery. Beginning in 1898, cervical sympathectomy became a widely performed operation around the world, with most surgeons enthusiastic about its results, at least initially, and many publications from 1898 to 1905 claimed excellent results for various types of glaucoma. Opponents of the procedure emphasized that the effect on IOP was transient, and that the published reports of successful results were poorly documented. The popularity of sympathectomy gradually diminished and by 1910 it was abandoned. I discuss the reasons why cervical sympathectomy received such initial enthusiasm but was then questioned and discarded. These included bias from the surgeons promoting this surgery; the placebo effect; short follow-up; inaccurate, subjective, and variable measures of the surgical results; and the development of more effective procedures such as filtering surgery and cyclodialysis.