Microvascular decompression for trigeminal neuralgia

Microvascular decompression for trigeminal neuralgia

see Microvascular decompression for trigeminal neuralgia and multiple sclerosis

see Awake Microvascular Decompression for Trigeminal Neuralgia

see also Endoscope assisted microvascular decompression for trigeminal neuralgia.

Microvascular decompression is a first-line neurosurgical approach for classical trigeminal neuralgia with neurovascular conflict, but can show clinical relapse despite proper decompression. Second-line destructive techniques like radiofrequency thermocoagulation have become reluctantly used due to their potential for irreversible side effects. Subcutaneous peripheral nerve field stimulation (sPNFS) is a minimally invasive neuromodulatory technique which has been shown to be effective for chronic localised pain conditions.

The most frequently used surgical management of trigeminal neuralgia is Microvascular decompression (MVD), followed closely by stereotactic radiosurgery (SRS). Percutaneous stereotactic rhizotomy (PSR) , despite being the most cost-effective, is by far the least utilized treatment modality 1).

Microvascular decompression (MVD) via lateral suboccipital approach is the standard surgical intervention for trigeminal neuralgia treatment.

Teflon™ and Ivalon® are two materials used in MVD for TN. It is an effective treatment with long-term symptom relief and recurrence rates of 1-5% each year. Ivalon® has been used less than Teflon™ though is associated with similar success rates and similar complication rates 2)

Although microvascular decompression (MVD) is the most effective long-term operative treatment for TN, its use in older patient populations has been debated due to its invasive nature.


Compared with the standard microscope-assisted techniques, the 3D exoscopic endoscope-assisted MVD offers an improved visualisation without compromising the field of view within and outside the surgical field 3).

Systematic Review and Meta-Analysis

Using preferred reporting items for systematic reviews and meta-analyses (PRISMA) guidelines, PubMedCochrane Library, and Scopus were queried for primary studies examining pain outcomes after MVD for TN published between 1988 and March 2018. Potential biases were assessed for included studies. Pain freedom (ie, Barrow Neurological Institute score of 1) at last follow-up was the primary outcome measure. Variables associated with pain freedom on preliminary analysis underwent formal meta-analysis. Odds ratios (OR) and 95% confidence intervals (CI) were calculated for possible predictors.

Outcome data were analyzed for 3897 patients from 46 studies (7 prospective, 39 retrospective). Overall, 76.0% of patients achieved pain freedom after MVD with a mean follow-up of 1.7 ± 1.3 (standard deviation) yr. Predictors of pain freedom on meta-analysis using random effects models included (1) disease duration ≤5 yr (OR = 2.06, 95% CI = 1.08-3.95); (2) arterial compression over venous or other (OR = 3.35, 95% CI = 1.91-5.88); (3) superior cerebellar artery involvement (OR = 2.02, 95% CI = 1.02-4.03), and (4) type 1 Burchiel classification (OR = 2.49, 95% CI = 1.32-4.67).

Approximately three-quarters of patients with drug-resistant TN achieve pain freedom after MVD. Shorter disease duration, arterial compression, and type 1 Burchiel classification may predict a more favorable outcome. These results may improve patient selection and provider expectations 4).

Technique

Outcome

Complications

Case series

References

1)

Sivakanthan S, Van Gompel JJ, Alikhani P, van Loveren H, Chen R, Agazzi S. Surgical management of trigeminal neuralgia: use and cost-effectiveness from an analysis of the medicare claims database. Neurosurgery. 2014 Sep;75(3):220-6. doi: 10.1227/NEU.0000000000000430. PubMed PMID: 24871139.
2)

Pressman E, Jha RT, Zavadskiy G, Kumar JI, van Loveren H, van Gompel JJ, Agazzi S. Teflon™ or Ivalon®: a scoping review of implants used in microvascular decompression for trigeminal neuralgia. Neurosurg Rev. 2019 Nov 30. doi: 10.1007/s10143-019-01187-0. [Epub ahead of print] Review. PubMed PMID: 31786660.
3)

Li Ching Ng A, Di Ieva A. How I do it: 3D exoscopic endoscope-assisted microvascular decompression. Acta Neurochir (Wien). 2019 May 29. doi: 10.1007/s00701-019-03954-w. [Epub ahead of print] PubMed PMID: 31144166.
4)

Holste K, Chan AY, Rolston JD, Englot DJ. Pain Outcomes Following Microvascular Decompression for Drug-Resistant Trigeminal Neuralgia: A Systematic Review and Meta-Analysis. Neurosurgery. 2020 Feb 1;86(2):182-190. doi: 10.1093/neuros/nyz075. PubMed PMID: 30892607.

Microvascular decompression for hemifacial spasm outcome

Microvascular decompression for hemifacial spasm outcome

Microvascular decompression is an effective treatment for hemifacial spasm. Given that postoperative delayed cure was unavoidable, even with accurate identification of the offending vessel and sufficient decompression of the root exit zone, the delayed cure should be considered in patients undergoing reoperation due to lack of remission or relapse after the operation. Additionally, the timing of efficacy assessments should be delayed 1).

The definitive treatment for hemifacial spasm is microvascular decompression (MVD), which cures the disease in 85% to 95% of patients according to reported series. In expert hands, the MVD procedure can be done with relatively low morbidity.

Post-operatively, there may be episodes of mild HFS, however they usually begin to diminish 2–3 days following MVD. Severe spasm that does not abate suggests failure to achieve adequate decompression, and reoperation should be considered.

Surgical results of MVD depends on the duration of symptoms (shorter duration has better prognosis) as well as on the age of the patient (elderly patients do less well). Complete resolution of HFS occurred in 44 (81%) of 54 patients undergoing MVD, however, 6 of these patients had relapse 2). 5 patients (9%) had partial improvement, and 5 (9%) had no relief.


Complete resolution of spasm occurs in ≈ 85–93% 3) 4) 5) 6) 7). Spasm is diminished in 9%, and unchanged in 6% 8). Of 29 patients with complete relief, 25 (86%) had immediate post-op resolution, and the remaining 4 patients took from 3 mos to 3 yrs to attain quiescence.

Recurrence

References

1)

Li MW, Jiang XF, Wu M, He F, Niu C. Clinical Research on Delayed Cure after Microvascular Decompression for Hemifacial Spasm. J Neurol Surg A Cent Eur Neurosurg. 2019 Oct 10. doi: 10.1055/s-0039-1698461. [Epub ahead of print] PubMed PMID: 31600810.
2)

Auger RG, Peipgras DG, Laws ER. Hemifacial Spasm: Results of Microvascular Decompression of the Facial Nerve in 54 Patients. Mayo Clin Proc. 1986; 61:640–644
3)

Rhoton AL. Comment on Payner T D and Tew J M: Recurren ce of Hemifacial Spasm After Microvascular Decompression. Neurosurgery. 1996; 38
4)

Jannetta PJ. Neurovascular Compression in Cranial Nerve and Systemic Disease. Ann Surg. 1980; 192:518–525
5)

Loeser JD, Chen J. Hemifacial Spasm: Treatment by Microsurgical Facial Nerve Decompression. Neurosurgery. 1983; 13:141–146
6)

Huang CI, Chen IH, Lee LS. Microvascular Decompression for Hemifacial Spasm: Analyses of Operative Findings and Results in 310 Patients. Neurosurgery. 1992; 30:53–57
7) , 8)

Payner TD, Tew JM. Recurrence of Hemifacial Spasm After Microvascular Decompression. Neurosurgery. 1996; 38:686–691

Recurrent hemifacial spasm after microvascular decompression

Recurrent hemifacial spasm after microvascular decompression

Microvascular decompression (MVD) is a highly effective treatment for hemifacial spasm (HFS), but even if the root exit zone (REZ) from the brainstem is adequately decompressed, residual spasms after surgery or early reappearance of spasms are not uncommon 1) 2) 3) 4) 5)

Return of symptoms after a period of complete resolution of hemifacial spasm occurs in up to 10% of patients, 86% of recurrences happen within 2 yrs of surgery, and the risk of developing recurrence after 2 yrs of post-op relief is only ≈ 1% 6).


Among more than 2500 patients who underwent microvascular decompression for hemifacial spasm, 23 patients received a second MVD in the Kyung Hee University Hospital from January 2002 to December 2017. Three-dimensional time of flight magnetic resonance angiography and reconstructed imaging were used to identify the culprit vessel and its conflict upon root exit zone (REZ) of the facial nerve. They reviewed patients’ medical records and operation videos to identify the missing points of the first surgery.

8 patients had incomplete decompression, such as single-vessel decompression of multiple offending vessels. Teflon was not detected at the REZ, but was found in other locations in 12 patients. Three patients had severe adhesion with previous Teflon around the REZ. Nineteen patients had excellent surgical outcomes at immediate postoperative evaluation; 20 patients showed spasm disappearance at 1 year after surgery and 3 patients showed persistent symptoms. Neuro-vascular contacts around REZ of facial nerve were revealed on MRI of incomplete decompression and Teflon malposition patient groups. There were no clear neuro-vascular contacts in the patients with severe Teflon adhesion.

The decision on secondary MVD for persistent or recurrent spasm is troubling. However, if the neurovascular contact was observed in the MRI of the patient and there were offending vessels, the surgical outcome might be favorable 7).

References

1)

Fukushima T: Microvascular decompression for hemifacial spasm: results in 2890 cases, in Carter LP, Spetzler RF, editors. (eds): Neurovascular Surgery. New York, McGraw-Hill, 1995, pp 1133–1145
2)

Huang CI, Chen IH, Lee LS: Microvascular decompression for hemifacial spasm: analyses of operative findings and results in 310 patients. Neurosurgery 30: 53– 56; discussion 56–57, 1992.
3)

Ishikawa M, Nakanishi T, Takamiya Y, Namiki J: Delayed resolution of residual hemifacial spasm after microvascular decompression operations. Neurosurgery 49: 847– 854; discussion 854–856, 2001.
4)

Li CS: Varied patterns of postoperative course of disappearance of hemifacial spasm after microvascular decompression. Acta Neurochir (Wien) 147: 617– 620; discussion 620, 2005.
5)

Shin JC, Chung UH, Kim YC, Park CI: Prospective study of microvascular decompression in hemifacial spasm. Neurosurgery 40: 730– 734; discussion 734–735, 1997.
6)

Payner TD, Tew JM. Recurrence of Hemifacial Spasm After Microvascular Decompression. Neurosurgery. 1996; 38:686–691
7)

Park CK, Lee SH, Park BJ. Surgical Outcomes of Revision Microvascular Decompression for Persistent or Recurrent Hemifacial Spasm after Surgery: Analysis of radiological and intraoperative findings. World Neurosurg. 2019 Aug 2. pii: S1878-8750(19)32107-2. doi: 10.1016/j.wneu.2019.07.191. [Epub ahead of print] PubMed PMID: 31382068.
WhatsApp WhatsApp us
%d bloggers like this: