Microvascular decompression for trigeminal neuralgia

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.

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.


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).

97 patients with primary trigeminal neuralgia (PTN) underwent fully endoscopic microvascular decompression (MVD) via keyhole approach in Capital Medical University Affiliated Beijing Shijitan Hospital from December 2014 to February 2019 was collected. During fully endoscopic MVD in PTN via keyhole approach, performer use natural clearance without grinding except developed rock bone crest or excessive retraction of the brain tissue, visually and panoramically observe and evaluate the CPA area, accurately identify the responsible vessels, to avoid the omission of responsible vessels or insufficient decompression. And the use of preplaced technology, bridging technology and submersible technology, ensure the efficacy of surgery and reduce the surgical side injuries. Barrow Neurological Institute Pain Intensity Score was used to evaluate the efficacy and identify the recurrence. The surgical efficacy was analyzed. The offending vessels were identified under endoscope in 96 cases. Among them, arterial compression was found in 77 cases, venous compression in 6 cases, and both arterial and venous compression in 13 cases. About the pain outcomes, 87 cases had immediate and complete relief of pain, 5 cases had almost relief of pain, 4 cases had partial relief of pain, and still needed medication control, but the dose was lower than that before operation, and 1 case had no obvious relief of pain. About complications, there were 4 cases of temporary facial numbness, 1 case of temporary hearing loss, both of them recovered after symptomatic treatment. There was no cerebral infarction or hemorrhage, intracranial or incision infection. All cases were followed up for 3.0-38.0 months with a median period of(22.4±2.2) months. During the follow-up periods, postoperative recurrence occurred in 3 cases. Fully endoscopic MVD for PTN through keyhole approach, provides panoramic view to avoid omission of offending vessels and reduce complications, seemed to be a safe and effective surgical method 4).

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 5).

Microvascular decompression for trigeminal neuralgia technique.

Microvascular decompression for trigeminal neuralgia outcome.

Microvascular decompression for trigeminal neuralgia complications

Microvascular decompression for trigeminal neuralgia case series.


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)

Peng WC, Guan F, Hu ZQ, Huang H, Dai B, Zhu GT, Mao BB, Xiao ZY, Zhang BL, Liang X. [Efficacy analysis of fully endoscopic microvascular decompression in primary trigeminal neuralgia via keyhole approach]. Zhonghua Yi Xue Za Zhi. 2021 Mar 30;101(12):856-860. Chinese. doi: 10.3760/cma.j.cn112137-20200630-02002. PMID: 33789367.
5)

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.

Trigeminal nerve

Trigeminal nerve

Johann Friedrich Meckel made the first description of the subarachnoid space investing the trigeminal nerve into the middle fossa.

Possible pathways for facial pain include: trigeminal nerve (portio major as well as portio minor (motor root).

Supratentorial sensory perception, including facial pain, is subserved by the trigeminal nerve, in particular, by the branches of its ophthalmic nerve, which provide an extensive innervation of the dura mater and of the major brain blood vessels. In addition, contrary to previous assumptions, studies on awake patients during surgery have demonstrated that the mechanical stimulation of the pia mater and small cerebral vessels can also produce pain. The trigeminovascular system, located at the interface between the nervous and vascular systems, is therefore perfectly positioned to detect sensory inputs and influence blood flow regulation. Despite the fact that it remains only partially understood, the trigeminovascular system is most probably involved in several pathologies, including very frequent ones such as migraine, or other severe conditions, such as subarachnoid hemorrhage. The incomplete knowledge about the exact roles of the trigeminal system in headacheblood flow regulationBlood-brain Barrier Permeability, and trigemino-cardiac reflex warrants for an increased investigation of the anatomy and physiology of the trigeminal system 1).

The trigeminal nerve complex is a very important and somewhat unique component of the nervous system. It is responsible for the sensory signals that arise from the most part of the facemouthnosemeninges, and facial muscles, and also for the motor commands carried to the masticatory muscles. These signals travel through a very complex set of structures: dermal receptors, trigeminal branches, Gasserian ganglion, central nuclei, and thalamus, finally reaching the cerebral cortex. Other neural structures participate, directly or indirectly, in the transmission and modulation of the signals, especially the nociceptive ones; these include vagus nervesphenopalatine ganglion, occipital nerves, cervical spinal cord, periaqueductal gray matter, hypothalamus, and motor cortex. But not all stimuli transmitted through the trigeminal system are perceivable. There is a constant selection and modulation of the signals, with either suppression or potentiation of the impulses. As a result, either normal sensory perceptions are elicited or erratic painful sensations are created 2).


Originating in the posterior fossa of the brain stem, it follows a long and complex course towards its distribution territory, crossing several regions with a complex anatomy and establishing important relationships with several structures.

The nerve fibers originate in the brainstem and are part of several grey matter nuclei occupying all the brainstem and even the first spinal cervical segments.

Each of these sensitive and motor nuclei represents different processing centers, and there is a true systematization of the information this nervous tract is responsible for conducting.

The sensitive nucleus is the largest, comprising 3 true sub-nuclei, each responsible for each aspect of the general sensitivity. The highest is the mesencephalic nucleus, located in the tegmentum close to the midline and to the grey matter close to the Sylvian aqueduct. The neurons that form this nucleus are in charge of the propioceptive integration in the Vth nerve territory, high level information for correct mastication. The main nucleus is in the pons, it is also situated in the depth of the tegmentum, and is responsible for the tactile integration of the territory of this nerve. Finally, the inferior nucleus occupies the tegmentum of the medulla, extending caudally to the first segments of the cervical spine, and is in charge of thermal and pain information. Its location explains the possible appearance of symptoms in the facial territory in patients with a degenerative/inflammatory disorder of the upper cervical spine. There is one single motor nucleus, located in the pons tegmentum supplying mastication muscles, and is correspondingly called mastication nucleus. The fibers related with all these nuclei gather in the pons and emerge through the lateral sector of its anterior aspect, forming a thick nervous tract with two roots: a thicker and lateral sensitive root and a thinner more medial motor root.

The only intra-axial segment of the Vth ends there and initiates its long course to its distribution territory; it is formed by different sub-segments before dividing itself into its terminal branches (the cisternal and Gasserian or transdural segments).

The point where the roots emerge in the brainstem is called “REZ” (Root Entry Zone), an anatomical landmark of great functional hierarchy.

see Trigeminal nerve cisternal portion.

The trigeminal nerve as the name indicates is composed of three large branches. They are the ophthalmic nerve (V1, sensory), maxillary nerve (V2, sensory), and mandibular nerve (V3, motor and sensory) branches. The large sensory root and smaller motor root leave the brainstem at the mid-lateral surface of pons.

The trigeminal nerve (the fifth cranial nerve, or simply CN V) is a nerve responsible for sensation in the face and certain motor functions such as biting and chewing. It is the largest of the cranial nerves. Its name (“trigeminal” = tri- or three, and -geminus or twin, or thrice twinned) derives from the fact that each trigeminal nerve, one on each side of the pons, has three major branches: the ophthalmic nerve (V1), the maxillary nerve (V2), and the mandibular nerve (V3). The ophthalmic and maxillary nerves are purely sensory. The mandibular nerve has both cutaneous and motor functions.

Sensory information from the face and body is processed by parallel pathways in the central nervous system. The motor division of the trigeminal nerve is derived from the basal plate of the embryonic pons, while the sensory division originates from the cranial neural crest.

see Trigeminal nerve sensory pathways.

Trigeminal nerve-related pathology.

see Trigeminal nerve imaging.


1)

Terrier LM, Hadjikhani N, Velut S, Magnain C, Amelot A, Bernard F, Zöllei L, Destrieux C. The trigeminal system: The meningovascular complex- A review. J Anat. 2021 Feb 18. doi: 10.1111/joa.13413. Epub ahead of print. PMID: 33604906.
2)

Goellner E, Rocha CE. Anatomy of Trigeminal Neuromodulation Targets: From Periphery to the Brain. Prog Neurol Surg. 2020 Oct 6;35:1-17. doi: 10.1159/000511257. Epub ahead of print. PMID: 33022684.

Ziconotide

Ziconotide

Decreasing the risk of granuloma formation. with ziconotide 1) have been indeterminate, with some case reports demonstrating regression 2) and others showing persistence of inflammation 3) after substitution.

Intrathecal drug therapy has been established as an effective treatment option for patients with chronic pain of malignant or non-malignant origin, with an established safety profile and fewer adverse effects, compared to oral or parenteral pain medications. Morphine (a μ-opioid receptor agonist) and ziconotide (a non-opioid calcium channel antagonist) are the only IT agents approved by the US Food and Drug Administration for chronic pain treatment. Although both are considered first-line IT therapies, each drug has unique properties and considerations.

A review of Chalil et al. will evaluate the pivotal trials that established the use of morphine and ziconotide as first-line IT therapy for patients with chronic pain, as well as safety and efficacy data generated from various retrospective and prospective studies.

Morphine and ziconotide are effective IT therapies for patients with chronic malignant or non-malignant pain that is refractory to other interventions. IT ziconotide is recommended as first-line therapy due to its efficacy and avoidance of many adverse effects commonly associated with opioids. The use of IT morphine is also considered first-line; however, the risks of respiratory depression, withdrawal with drug discontinuation or pump malfunction, and the development of tolerance require careful patient selection and management 4).


Shao et al. showed that ziconotide intrathecal drug therapy improves pain as well as emotional components and function. The study adds prospective evidence to the literature on IDT for neuropathic pain, specifically its role in improving disability, emotional well-being, and catastrophizing 5).

Staub et al. reported the first case describing the use of a single-shot lumbar intrathecal trial of ziconotide and subsequent placement of lumbar (as opposed to thoracic) intrathecal ziconotide pump for persistent idiopathic facial pain (PIFP). A single-injection intrathecal trial is a low-risk, viable option for patients with this debilitating and frustrating pain condition. Successful trials and subsequent intrathecal pump placement with ziconotide may supplant multimodal medication management and/or invasive orofacial surgical intervention for PIFP 6).


1)

Deer TR, Prager J, Levy R, et al. Polyanalgesic Consensus Conference–2012: consensus on diagnosis, detection, and treatment of catheter-tip granulomas (inflammatory masses). Neuromodulation. 2012; 15: 483–95; discussion 496
2)

Codipietro L, Maino P. Aseptic arachnoiditis in a patient treated with intrathecal morphine infu- sion: symptom resolution on switch to ziconotide. Neuromodulation. 2015; 18:217–20; discussion 220
3)

Tomycz ND, Ortiz V, McFadden KA, et al. Management of symptomatic intrathecal catheter- associated inflammatory masses. Clin Neurol Neurosurg. 2012; 114:190–195
4)

Chalil A, Staudt MD, Harland TA, Leimer EM, Bhullar R, Argoff CE. A safety review of approved intrathecal analgesics for chronic pain management. Expert Opin Drug Saf. 2021 Feb 15. doi: 10.1080/14740338.2021.1889513. Epub ahead of print. PMID: 33583318.
5)

Shao MM, Khazen O, Hellman A, Czerwinski M, Dentinger R, DiMarzio M, Gillogly M, Hadanny A, Argoff C, Pilitsis JG. Effect of First-Line Ziconotide Intrathecal Drug Therapy for Neuropathic Pain on Disability, Emotional Well-Being, and Pain Catastrophizing. World Neurosurg. 2021 Jan;145:e340-e347. doi: 10.1016/j.wneu.2020.10.079. Epub 2020 Oct 20. PMID: 33096281.
6)

Staub BP, Casini GP, Monaco EA 3rd, Sekula RF Jr, Emerick TD. Near-resolution of persistent idiopathic facial pain with low-dose lumbar intrathecal ziconotide: a case report. J Pain Res. 2019 Mar 8;12:945-949. doi: 10.2147/JPR.S193746. PMID: 30881103; PMCID: PMC6413753.
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