Treatments

Percutaneous destructive neurosurgical techniques (radiofrequency thermocoagulation, glycerol rhizolysis, or balloon compression)

In this section:

Key points | Benefits and Harms | Comment

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Key points

  • For GRADE evaluation of interventions for Trigeminal neuralgia, see table.
  • We found no RCT evidence assessing percutaneous destructive neurosurgical techniques (radiofrequency thermocoagulation, glycerol rhizolysis, or balloon compression) versus placebo/no treatment or other treatments covered in this review in people with trigeminal neuralgia.
  • There is some observational data suggesting that radiofrequency thermocoagulation may offer higher rates of complete pain relief than glycerol rhizolysis and stereotactic radiosurgery, but is associated with the highest rate of complications (e.g., facial numbness and corneal insensitivity).
  • Percutaneous destructive neurosurgical techniques require sedation and, sometimes, general anaesthesia before they are performed.
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Benefits and harms

Percutaneous destructive neurosurgical techniques (radiofrequency thermocoagulation, glycerol rhizolysis, or balloon compression):

We found four systematic reviews (search date 2003;[54][55][56] search date 2010[57]), which identified no RCTs comparing percutaneous destructive neurosurgical techniques (radiofrequency thermocoagulation, glycerol rhizolysis, or balloon compression) versus placebo/no treatment or versus other treatments covered in this review.

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Comment

As Clinical Evidence was unable to perform a second appraisal of results retrieved by the contributor's search, we may have missed studies that could affect our overall assessment of this intervention.

Clinical guide:

One of the systematic reviews (search date 2003)[54] identified nine observational studies (mainly case series, 2077 people) comparing percutaneous destructive neurosurgical techniques to the Gasserian ganglion and/or pre-ganglionic nerve route versus stereotactic radiosurgery. It suggested that radiofrequency thermocoagulation may offer higher rates of complete pain relief than glycerol rhizolysis and stereotactic radiosurgery (a non-percutaneous destructive neurosurgical technique), but it is also associated with the highest rate of complications. RCTs comparing the effects of percutaneous destructive neurosurgical techniques with no treatment have not been undertaken and are unlikely to be in future because of ethical considerations.

We did identify one small prospective comparative cohort observational study comparing radiofrequency thermocoagulation with glycerol rhizolysis.[67] This low-quality evidence study of 79 people with relatively short median follow-ups of 24 to 36 months for each technique showed better pain control results for radiofrequency thermocoagulation compared with glycerol rhizolysis (85% v 59%, P < 0.05) based on raw data, but this difference lost significance when life-table analysis was applied (P = 0.51).

One of the systematic reviews (search date 2010)[57] identified a small RCT comparing pulsed radiofrequency thermocoagulation versus conventional radiofrequency thermocoagulation.[68] Everyone in the pulsed radiofrequency thermocoagulation treatment group dropped out and needed conventional radiofrequency thermocoagulation. Furthermore, everyone in the pulsed radiofrequency thermocoagulation group required additional carbamazepine and/or gabapentin, compared with one person in the conventional radiofrequency thermocoagulation group. We found a similar study assessing combined pulsed radiofrequency and continuous radiofrequency.[69] The benefits of pulsed radiofrequency thermocoagulation in treating trigeminal neuralgia appear to be limited.

The main complications associated with radiofrequency thermocoagulation are facial numbness and corneal insensitivity. Although radiofrequency thermocoagulation runs the risk of adding to the problem of de-afferentation and trigeminal neuralgia pain, sensory loss in the area of facial pain appear to correlate with the best chance of pain relief and durability of response when used as a first percutaneous destructive neurosurgical technique.[54]

Similar to microvascular decompression, but unlike stereotactic radiosurgery, percutaneous destructive neurosurgical techniques can achieve immediate pain relief.[70][71][72][73][74][75][76][77][78][79][80][81] These procedures can therefore be considered along with microvascular decompression for the emergency management of people with trigeminal neuralgia in acute extremis. However, the duration of response with percutaneous destructive neurosurgical techniques is shorter than that of microvascular decompression.[50][44][54] Furthermore, these procedures require a brief pulse of heavy sedation and, sometimes, general anaesthesia before they are performed.

Percutaneous destructive neurosurgical techniques can be repeated for trigeminal neuralgia pain recurrence, but the damage to the nerve is cumulative. Each re-treatment is, therefore, associated with a cumulative higher risk of trigeminal de-afferentation.[82][83] De-afferentation pain, in addition to trigeminal neuralgia pain, could then become a problem.

As with stereotactic radiosurgery, percutaneous destructive neurosurgical techniques can be used to treat multiple sclerosis-associated trigeminal neuralgia, albeit with somewhat lower anticipated success rates.[84][85]