Modern trends in surgical treatment of trigeminal neuralgia

315 J. max.-fac, Surg, 7 (1979) 315-319

Modern Trends in Surgical Treatment of Trigeminal Neuralgia Beniamino GUIDETTI,Bernardo ~TRAIOLI,Gianni Marino REFICE

Neurosurgical institute (Director: Prof. B. Guidetti, M.D.), University of Rome, Italy Summary From 1955 to July 1978, 560 patients suffering from trigeminal neuralgia, who had not responded to medical treatment underwent various alternative procedures. Considering some of these to be out of date, some as showing too high a number of relapses and some as having potentially unjustified risks in an affection in itself not fatal, the authors report only the results observed in a series of 175 patients operated on by retrogasserian rhizotomy according to Frazier (1931), and the results of a series of 184 patients treated by controlled thermocoagulation according to Sweet and Wepsic (1974). Key-Words: Trigeminal neuralgia; Medical t:teatment; Alternative treatment; Controlled thermocoagulation. Introduction Chronic paroxysmal trigeminal neuralgia (or "tic douloureux", or "essential" trigeminal neuralgia) is an extremely painful affection of unknown aetiopathology which usually occurs in middle or old age. It consists of painful, lancinating and shooting but not burning, atta&s, triggered off by facial movements, such as during speaking, drinking, chewing, etc.; and touching particular facial areas, during washing the face or cleaning the teeth or shaving, often provokes the attacks, which are generally unilateral and confined exactly to the trigeminal divisions. The attacks are short, usually lasting for seconds or minutes, and vegetative phenomena, such as salivation, facial flushing and lacrimation, are usually associated. Between attacks or series of atta&s the patient feels well and it should be noted that at the beginning of the affection there are pain-free periods lasting months or years. The touching of the facial points of emergence of the trigeminal nerve ("trigger zones") characteristically provokes the attacks and it should be noted that blocking them with anaesthetics temporarily relieves the pain, while all the analgesic drugs, morphine included, give little benefit to the patient. Neurological examination is negative. 0301-0503/79

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It is known that when medical treatment for trigeminal neuralgia fails, there are many therapeutic alternatives, for minor procedures as well as major surgical interventions. However, our experience over more than twenty years indicates that only two types of treatment are to be considered, both with little risk and both able to give satisfactory results: retrogasserian rhizotomy (Frazier 1931) and control,led thermocoagulation (Sweet and Wepsic 1974). Therefore, in this article we report only the results achieved by these two methods.

Material and Method Of 560 patients treated for trigeminal neuralgia intractable to medical procedures between 1955 and July 1977; we report the results observed in a series of 175 patients operated on by retrogasserian rhizotomy according to Frazier (1931), and the results of a series of 184 patients treated by means of controlled differential thermocoagulation according to Sweet and Wepsic (1974). With regard to the patients operated on by retrogasserian rhizotomy, it should be noted that 172 of them were suffering from "essential" trigeminal neuralgia and 3 from trigeminal neuralgia associated with multiple sclerosis. The age of the majority of the patients ranged from sixty to seventy years and all were operated on according to the technique described by Frazier (1931). With regard to the patients treated by means of controlled thermocoagulation, 167 of them were suffering from "essential" trigeminal neuralgia; 9 from trigeminal neuralgia associated with multiple sclerosis; 4 from symptomatic neuralgia due to lymphoepithelioma of the pharynx or cheek carcinoma; 3 from atypical neuralgia and one from postherpetic neuralgia. The age of the majority of the patients ranged from fifty to seventy years and all were treated according to the technique .described by Sweet and Wepsic (1974), except for the use, in the great majority of

© 1979 Georg Thieme Publishers

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B. Guidetti, B. Fraioli, G. M. Refice

Table 1 Results following retrogasserian rhizotomy according to Frazier (1931)in 175 patients. Conditions

No. Patients

Success

Failure

"Essential" trigeminal neuralgia Trigeminal neuralgia in multiple sclerosis

172 3

170 3

2 (for painful anesthesia) -

Table 2 Complications after retrogasserian rhizotomy in 175 patients. Mortality Undesired first-division anaesthesia or hypo-aesthesia Neuroparalytic keratitis Painful anaesthesia Transitory lesion of 7th cranial nerve Paraesthesias which required transitory antianxiety medication Herpes

0 8 1 2 5 14 31

Relapses (average follow-up: 10 years) - 12 patients (8 underwent a second successful operation; 4 were treated by means of controlled thermocoagulation).

patients, of fluoroscopic control throughout the entire procedure.

Results Following Retrogasserian Rhizotomy Success was achieved in 173 patients and the loss of sensation following the procedure was, in the great majority of patients, exactly confined to the trigeminal divisions which the operator wanted to render anaesthetic or hypoaesthetic. Almost all of the patients felt anaesthesia in the division treated, but almost all of them accepted such defects with gratitude and anti-anxiety medication was only required transitorily by 14 patients. However, another two patients developed the painful anaesthesia syndrome (Table 1). In a follow-up averaging 10 years, relapse of the neuralgia occurred .in 12 patients, the first eight of whom underwent a second operation, while the other four were treated by means of controlled thermocoagulation. There was no mortality, and a low complication rate was observed (Table 2). As shown, 8 patients disFlayed unwanted first division anaesthesia or hypo-aesthesia, ,but only one developed neuroparalytic keratitis; moreover five other patients showed transitory lesions of the 7th cranial nerve

and two the painful anaesthesia syndrome already mentioned. We have also reported 31 cases of postoperative herpes in the trigeminal divisions treated; this complication was not important because it lasted only a few days, but we think it is interesting to note, since it was so frequent in the present series and, on the contrary, absent in the other series treated by controlled thermocoagulation.

Results Following Thermocoagulation As shown in Table 3, in all 167 patients but one, suffering from "essential" neuralgia, the painful attacks ceased completely following the procedure, and it should be noted that in 158 analgesia, or rarely hypo-algesia, was produced while preserving some touch sensation. One patient developed painful anesthesia several months following the procedure and it should be noted that he was one of the nine patients in whom complete loss of sensation occurred in the trigeminal divisions treated. In all nine patients suffering from trigeminal neuralgia occurring in multiple sclerosis and in all four patients with symptomatic neuralgia, success was observed following the procedure. In the three patients suffering from atypical neuralgia, failure was observed in two, and it should be noted that some weeks after the procedure one of these developed painful hypo-aesthesia, although facial sensation was partially preserved. Failure was observed also in the patient suffering from postherpetic trigeminal neura,lgia. Complications following thermocoagulation were rare and, as shown in Table 4, these consisted of unwanted first-division analgesia or anaesthesia in 7 patients, but showing no ocular complication until now; transitory weakness of masticatory muscles in 6 patients and a transitory lesion of the 6th cranial nerve in one. Moreover, in addition to the two cases already mentioned of painful anaesthesia and hypo-aesthesia, it should be noted that eight patients required anti-anxiety medi-

Modern Trends in Surgical Treatment of Trigeminal Neuralgia

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Table 3 Results following thermocoagulation in 184 patients according to Sweet and Wepsic (1974). Condition

No. Patients

Success

Failure

"Essential" trigeminal neuralgia Trigeminal neuralgia in multiple sclerosis Symptomatic neuralgia Atypical neuralgia

167 9 4 3

166 9

1 (for painful anesthesia

Postherpetic neuralgia

i

cation for paraesthesias, but only transitorily. Lastly, one patient showed a transitory haematoma of the orbit due to a wrong trajectory of the needle, but this occurred in one of the first patients treated, When fluoroscopic control was not yet in use. The relatively brief follow-up averaging two years, probably does not give the real picture of the recurrence rate of neuralgia; however, as shown in Table 2, it should be noted that only six patients have presented with relapse of the neurMgia to date and that in all these patients only hypoalgesia and not analgesia was produced. In any case, ajll these patients underwent a second successful procedure. Discussion

Our experience in patients treated with medical procedures for trigeminal neuralgia agrees with those authors (Blom 1963, Kiluk et al. 1968, Szuba et al. 1973, Fassauer et al. 1974) who have reported that the first method to choose in the treatment of "essential" trigeminal neuralgia should be medical treatment with carbamazepine. Actually, if side effects such as asthenia, dizziness, drowsiness, etc., can be noted frequently enough following this treatment, they very seldom lead to withdrawal of the drug. However, it should b.e noted that Kiluk et al. (1968) have reported one case of mortality from aplastic anaemia due to treatment with carbamazepine; and so this treatment should be considered as potentially hazardous and periodic laboratory checking is required. There are many alternative therapeutic procedures when medical therapy fails. These include minor procedures such as nerve avulsions peripherally, instillation of alco.ho(1 or phenol into Meckel's cave, Gasserian ganglion electrocoagula-

4 1

2 (in 1, painful hypoaesthesia) 1

Table 4 Complications following thermocoagulation in 184 patients. Undesired first-division analgesia or anaesthesia Painful anaesthesia or hypo-aesthesia Transitory weakness of masticatory muscles Transitory lesion of 6th cranial nerve Paraesthesias which required transitory antianxiety medication Transitory haematoma of the orbit

7 2 6 l 8 l

Relapses (average follow-up: 2 years) - 6 patients, in divisions which were made only hypoalgesic. All underwent a second successful procedure.

tion according to Kirschner (1936), controlled thermocoagulation of the trigeminal ganglion and rootlets according to Sweet and Wepsic (1974); moreover, major procedures are also available, such as trigeminal nerve rhizotomy at the pons according to Dandy (1925), extradural retrogasserian rhizotomy according to Frazier (1931) or intradural retrogasserian rhizotomy according to Wilkins (1966), decompression of trigeminal root and gasserian ganglion according to Taarnho] (1952), bulbar tractotomy according to S](}quist (1938), the microsurgica] approach through the posterior fossa according to Jannetta (1976). Each procedure has its advocates, but the very multiplicity of choices is obviously disconcerting. Our experience covering more than twenty years includes almost all the minor procedures which were, and are in use and all the major procedures. W e feel that peripheral alcoholization or phenolization, as well as nerve avulsions peripherally, should be considered as procedures only temporarily effective, which furthermore do not preserve some touch sensation; and we feel that instilla-

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B. Guidetti, B. Fraioli, G. M. Re[ice

tion of alcohol or phenol into Meckel's cave should be considered out of da.te procedures today because not only they do not allow production of lesions differential between painful or tactile trigeminal fibres, nor the production of lesions confined to the trigeminal divisions affected by the neuralgia, but also they are not safe enough, because of the uncontrollable spread of the injected chemicals. Moreover, Gasserian ganglion electrocoagulation according to Kirschner (1936) should be considered a technique less advantageous than controlled thermocoagulation according to Sweet and Wepsic (1974), since these authors have documented that thermocoagulation is a more safe technique than electrocoagulation and that controlled increments of radiofrequency heating allow the production of lesions more differential between painfu~l or tactile trigeminal fibres than electrocoagulation. Finally, Taarnhoj's (1952) and Sjfquist's (1938) methods have the disavantage of a high number of relapses and Dandy's (1925) and Jannetta's (1976) methods have potential hazards not justified for an affection in itself non-fatal. Thus, we think that only two methods may be considered both effective and potentially not dangerous, i.e. retro-gasserian rhizotomy and controlled thermocoagulation. Moreover, we have found that controlled thermocoagulation has several advantages over retrogasserian rhizotomy: it is simpler, even if open retrogasserian rhizotomy is usually much quicker, and neuroleptanaesthesia is sufficient for its execution; fewer complications are generally to be expected and, lastbutnotleast, thermo,coa,gulation allows a much shorter postoperative hospitalization, usually 12-24 hours. With regard to the qualitative differences between the two methods, it should be noted that even after thermocoagulation the patients felt more or less unpleasant sensations in the trigeminal divisions treated, although in a lesser degree than after retrogasserian rhizotomy; moreover, the incidence of painful anaesthesia or hypoaesthesia was the same following the two methods. In effect, at the same time as thermocoagulation produces analgesia, it also produces loss of exteroceptive sensation, and only proprioceptive sensation can be preserved. Only by producing

hypoalgesia can a partial preservation of all sensory modalities be obtained, but in so doing painrecurrence is possible and eventually a second procedure has to be planned. For these reasons, we think that analgesia should be produced only in old non-apprehensive patients suffering from 3rd and/or 2nd .division trigeminal neuralgia; at the same time, only hypoalgesia should be produced in young or apprehensive patients, since thermocoagulation in a procedure repeatable without increased difficulty or hazard. In any case, only hypoalgesia should be produced in the first trigeminal division, in order to preserve the corneal reflex. Conclusion

In conclusion, we feel that the method of choice for the treatment of trigeminal neuralgia should be medical treatment with carbamazepine, while the alternative method of choice should be controlled differential thermocoagulation according to Sweet and Wepsic (1974). This latter method has several advantages over retrogasserian rhizotomy according to Frazier (1931). As regards the other procedures avai,lable today, we feel that Gasserian ganglion electrocoagulation (Kirschner 1936) should be considered a technically oldfashioned method, while peripheral alcoholization or phenolization should be considered only temporarily effective methods and not suitable for production of lesions differential between painful or tactile trigeminal fibres. Moreover, we feel that instillation of alcohol or phenol into Meckel's cave are not absolute.ly selective, and potentially dangerous methods. Lastly, bulbar tractotomy according to Sj6quist (1938) and decompression of the trigeminal root and Gasserian ganglion according to Taarnhoj (1952) have the disavantage of a high number of relapses, while trigeminal nerve rhizotomy at the pons according to Dandy (1925) and the microsurgical approach through the posterior fossa according to Jannetta (1976) are potentially hazardous methods. References

Blom, S.: Tic douloureux treated with new anticonvulsant: experience with G 32883. Arch. Neurol. 9 (1963) 285-290 Broggi, G.: Thermorhizotomy in trigeminal neuralgia: preliminary considerations on 46 cases. In: Penz-

Modern Trends in Surgical Treatment of Trigeminal Neuralgia holz, H. et al.: Brain, Ipoxia, Pain. Advanc. Neurosurg. 3 (1975) 297-299 Dandy, W . E.: Section of the sensory root of trigeminal nerve at the pons. Preliminary report of the operative procedure. Bull. Johns Hopkins Hosp. 36 (1925) 105-106 Fassauer, G., C. Schreiter, K. Boehm: Conservative medical treatment of facial neuralgias. Stomat. ddr. 24 (1974) 471-482 Fraioli, B.: Controlled Differential Thermocoagulation in the treatment of trigeminal neuralgia. J. Neurosurg. Sci. 22 (1978) 71-76 Frazier, C. H.: Radical operations for major trigeminal neuralgia. J. Amer. med. Ass. 96 (1931) 913-916 Guidetti, B.: Tractotomy for relief of trigeminal neuralgia. Observations in 124 cases. J. Neurosurg. 7 (1950) 499-508 ]anne~ta, P. ].: Microsurgical approach to the trigeminal nerve for tic douloureux. Prog. Neurol. Surg. 7 (1976) 180-200 Kiluk, K. I., R. S. Knighton, ]. D. Newman: The treatment of trigeminal neuralgia and other facial pain with carbamazepine. Mich. Med. 67 (1968) 1066-1069 Kirschner, M.: Zur Behandlung der Trigeminusneuralgie. Erfahrungen an 250 Ffillen. Arch. klin. Chir. 186 (1936) 325-334

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Morello, G., M. Bianchi, F. Migliavacca: Combined extradural temporal rhizotomy for the treatment of trigeminal neuralgia. Results in 409 patients. J. Neurosurg. 34 (1971) 372-379 Sj6quist, 0.: Studies on pain conduction in the trigeminal nerve. A contribution to the surgical treatment of facial pain. Acta psych. Koh. Suppl. 17 (1938) 139 Szuba, S., Z. Dobaczewski, F. Cwioro: Amizepin in idiopathic trigeminal neuralgia. Pol. Tyg. Lek. 28 (1973) 218-221 Sweet, W . H., ]. G. Wepsic: Controlled thermocoagulation of trigeminal ganglion and rootlets for differential destruction of pain fibers. Part I: Trigeminal neuralgia. J. Neurosurg. 40 (1974) 143-156 Taarnhoj, P.: Decompression of th.e trigeminal root and the posterior part of the ganglion as treatment in trigeminal neuralgia: preliminary communication. J. Neurosurg. 9 (1952) 288-290 Wilkins, H.: The treatment of trigeminal neuralgia by section of the posterior sensory fibers using th.e transdural temporal approach. J. Neurosurg. 25 (1966) 370-378 Benlamlno Guidetti, M.D. Bernardo Fraioli, M.D. lstituto di Neurochlrurgia dell'Universltd di Roma Viale dell'Universitd, 80, 00185 Roma, Italy