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Show /. Clin. Neuro-ophthalmol. 3: 227-228, 1983. An Oculinum Report In recent years, we have witnessed the introduction of many exciting diagnostic and therapeutic modalities in neuro-ophthalmology. Virtually everyone interested in the field is aware of such new procedures as digital subtraction angiography, nuclear magnetic resonance, and PET scanning. Similarly, enthusiasm has been generated by such therapeutic drugs as bromocriptine, Clonopin and Inderal. However, one therapeutic procedure with great potential application in neuro-ophthalmology has been generally ignored. I am referring, of course, to the use of Oculinum, which can cause temporary paralysis of the extraocular muscles and produce muscular atrophy when injected into the orbicularis. Dr. Alan Scotti of San Francisco has pioneered its use, especially for the treatment of strabismus. In addition, he has employed it in patients with essential blepharospasm, traumatic muscle palsies (to prevent contracture), and in thyroid eye disease (to release muscular restriction). Treatment of these last three conditions is of great interest to the neuro-ophthalmologist. Being by nature a "Doubting Thomas," I recently visited Dr. Scott and observed first-hand the treatment of six patients and the follow-up examination of 15 post-treatment cases. It became clear, to me at least, that this modality had greater application in neuro-ophthalmologic motility problems than in routine strabismus. Two of Dr. Scott's follow-ups were patients with essential blepharospasm. One, 5-6 months post-therapy, was doing well and the other patient, who had been treated successfully on one side, had returned for treatment of the other side. There was no severe exposure, ectropion, or attendant face or brow droop on the treated side. Having seen and treated a large number of patients with blepharospasm, these results were very impressive. While medical therapy in mild-to-moderate cases of blepharospasm can be helpful, it has been my personal experience that few patients with severe disease respond to any form of pharmacologic therapy. I have found myself frequently resorting to differential section of the facial nerve2 in these refractory cases. While these patients are by and large happy postoperatively just to be rid of the blepharospasm, this treatment is still less than satisfactory because of the attendant complications and tendency for recurrence. Newer surgical procedures have been advocated by Anderson3 and McCord4 with a reportedly lower incidence of side effects. However, they still involve a significant amount of surgery, and like differential section, December 1983 Editorial are usually done under general anesthesia, frequently taking 2 112-3 hours to perform. Conversely, Dr. Scott, using an initial dose of 5 X 10-3 meg (1/ 400 of the lethal dose) diluted in 2.0 ml of saline, injects 0.4 ml medially and 0.4 ml laterally along the lower lid margin, and 0.6 ml medially and 0.6 ml laterally in the upper lid, avoiding the central tarsal area and levator complex. The procedure takes 5 minutes and the maximum effect is reached in 1-2 days. There is no need for hospitalization and no anesthetic is given. A certain percentage of these patients will need to be reinjected at a later date, and occasionally an initial ptosis will accompany the orbicularis weakness. The short-term results appear excellent, and if these are shown to persist over time, this will represent a workable solution to a difficult problem. Additionally, patients with traumatic sixth nerve palsies and medial rectus contraction in whom surgery would not be considered for many months could be greatly aided by Oculinum injection of the medial rectus, thus reducing contracture and allowing the eye to settle in the primary position. If medial rectus contraction is not prevented, of course, even complete resolution of the palsy can be accompanied by a comitant esotropia. Patients with restrictive thyroid ophthalmopathy and severe diplopia would also appear to be good candidates for this therapy. Prisms, of course, can be used in mild cases, but in severe restrictions with a chin-elevated position injection of oculinum into the inferior recti can temporarily reduce the contraction where surgery would not be considered for many months. Finally, severely injured neurosurgical patients who would otherwise require a tarsorrhaphy can benefit from an injection of oculinum into the levator, resulting in a temporary paralysis of 3-4 weeks and eliminating the need for such a procedure. One of the main limitations of this therapy has been that the length of extraocular muscle paralysis is temporary and unpredictable, usually lasting a shorter period of time than desired. According to Dr. Scott, there have been no permanent paralyses of an extraocular muscle following an Oculinum injection. Unlike the extraocular muscles, the orbicularis and other peripheral muscles usually develop atrophy following the use of Oculinum. Although surgery in many strabismus cases can accomplish the same end as the injection of oculinum, it appears to be more complicated and less predictable in neuro-ophthalmologic motility conditions, suggesting the need for considering other 227 Editorial: Oculinum Report forms of therapy such as Ocu!inum. I would encourage those physicians actively engaged in neuro-ophthalmology to at least consider Ocu! inurn as an alternative form of therapy in such conditions as essential blepharospasm, traumatic sixth nerve palsy, and severe restrictive thyroid ophthalmopathy. Patrick S. O'Connor, M.D. The University of Texas Health Science Center at San Antonio San Antonio, Texas References 1. Scott, A. B.: Botulinum toxin injection of eye muscles to correct strabismus. Trans. Am. Ophthalmol. Soc. 228 79: 734-770, 1981. 2. Reynolds, D. H.: Differential section of the facial nerve for blepharospasm. In Neuro-ophthalmology : Symposium of the University of Miami in the Bascom Palmer Eye Institute, Vol. 4. C V. Mosby Co., St. Louis, 1968, pp. 190-200. 3. Gillum, W. N., and Anderson, R. L.: Blepharospasm surgery an anatomical approach. Arch. Ophthalmol. 99: 1056-1062, 1981. 4. McCord, C, et al.: Blepharospasm: Result~ of neurectomy vs. myectomy. (In press.) Write for reprints to: Patrick S. O'Connor, MD., Dept. of Ophthalmology, The University of Texas Health Sciences Center at San Antonio, San Antonio, Texas 78284. Journal of Clinical Neuro-ophthalmology |