Gregg Goldin, MD Timothy Miller, MD 9/28/18 Neurology and Neurosurgery Grand Rounds

Transcription

1 Trigeminal Neuralgia (tic douloureux) Gregg Goldin, MD Timothy Miller, MD 9/28/18 Neurology and Neurosurgery Grand Rounds

2 Disclosures -None

3 Objectives 1) Epidemiology, pathophysiology, and medical management (GG) 2) Surgical options (TM) 3) Radiosurgical option (GG)

4 Debilitating neuropathic condition involving the fifth (trigeminal) cranial nerve Chronic facial pain disorder Severe/episodic Typically unilateral Usually affects mandibular and maxillary divisions Isolated involvement of the ophthalmic division is much less common

5 Early 1500 s: Leonardo da Vinci sketches the cranial nerves 1600: Johannes Fehr and Elias Schmidt (secretaries of philosopher John Locke) describe the clinical entity 1756: Nicolas Andre coined the term tic douloureux 1773: John Fothergill described the first case series 1820: Charles Bell first localized the pain to the trigeminal nerve 1925: Walter Dandy sectioned the trigeminal nerve Late 1960 s: Peter Jannetta introduced the microvascular decompression (MVD) 1971, Lars Leksell treated first patient with stereotactic radiosurgery (SRS) Nicolas Andre John Fothergill

6 Epidemiology Prevalence = ~40,000 Incidence = ~15,000/year Condition of elderly Slightly more common in Women >$100 million spent on procedures alone annually in the US Harsha KJ, et al. Imaging of vascular causes of trigeminal neuralgia. J Neuroradiol. 2012;39(5):281 9 Mauskop A. Trigeminal neuralgia (tic douloureux). J Pain Symptom Manage. Apr 1993;8(3):148-54

7 Natural History (Classical TN) Misdiagnosed and under treated No clear natural history Paroxysmal attacks Pain tends to occur in cycles Pain-free intervals typically grow shorter Patients often live in fear and anticipation

8 Natural History Triggers: sensory stimulation touch, certain head movements, talking, chewing, swallowing, shaving, brushing teeth, or even a cold draft. In many, pain is generated spontaneously Stabbing electric shocks, burning, sharp, pressing, crushing, exploding or shooting pain

9 Pathophysiology Believed to involve loss of the myelin around the trigeminal nerve Etiologies include: Neurovascular compression (most commonly accepted) at TN entrance into the brainstem (pons). In one study, 64% of the compressing vessels were identified as an artery, most commonly the superior cerebellar (81%). Multiple Sclerosis Tumor Arteriovenous Malformation Facial Injury Pamir MN, et al. Microvascular decompression in the surgical management of trigeminal neuralgia. Neurosurg Rev. 1995;18(3): Samadian M, et al. Trigeminal Neuralgia Caused by Venous Angioma: A Case Report and Review of the Literature. World Neurosurg. 2015;84(3): Lummel N, et al. Diffusion tensor imaging of the trigeminal nerve in patients with trigeminal neuralgia due to multiple sclerosis. Neuroradiology. 2015;57(3):

10 Pathophysiology Mechanical compression often occurs as the nerve leaves the pons Nerve region especially susceptible to pathologic changes from vascular contact is the Redlich- Obersteiner s zone, also known as the root entry zone (REZ). REZ is characterized by nerve axons ensheathed in central myelin, transitioning to peripheral myelin. Agrawal SM, Kambalimath DH. Trigeminal neuralgia involving supraorbital and infraorbital nerves. Natl J Maxillofac Surg. 2010;1(2):

11 Neurophysiological Mechanism Ignition Therory Vascular contact leads to instability and atrophy Nerves become hyperexcitable and generate abnormal discharges Spontaneous firing results in burning and paresthesias Cascade propagation to the trigeminal nucleus is perceived as burst of pain. Intense flares from synchronization of bursts ephaptic crosstalk increased ions or neurotransmitters in the interstitial space Devor M, Amir R, Rappaport ZH. Pathophysiology of trigeminal neuralgia: the ignition hypothesis. The Clinical journal of pain. 2002;18(1):4 13.

12 Diagnosis of exclusion Diagnosis Neuro exam findings are usually normal. Rapid spreading of pain, bilateral affliction, or involvement of other cranial nerves suggests a systemic cause multiple sclerosis expanding cranial tumors Nerve compression on MRI often not visualized Blood work indicated if medical therapy is contemplated or to exclude collagen vascular diseases Haines SJ, Jannetta PJ, Zorub DS. Microvascular relations of the trigeminal nerve: an anatomical study with clinical correlation. Journal of neurosurgery. 1980;52(3): Hamlyn PJ, King TT. Neurovascular compression in trigeminal neuralgia: a clinical and anatomical study. Journal of neurosurgery. 1992;76(6):

13 Trigeminal neuropathy Differential Diagnosis postherpetic neuralgia (PHN) Neoplasms Granulomatous inflammation odontogenic pain, geniculate neuralgia, glossopharyngeal neuralgia, temporomandibular disorders, sinusitis, cluster headache, hemicrania, and SUNCT (short-lasting, unilateral neuralgia from headache attacks with conjunctival injection and tearing) syndrome

14 World Neurosurg Feb;98: doi: /j.wneu Epub 2016 Oct 27. MRI Characteristics MRI (using heavily T2 weighted (FIESTA) sequences) to visualize cranial nerves and exclude neoplasia Anatomical Volume: depletion of the trigeminal nerve volume is correlated with TN Neurovascular compression Functional Decreased Fractional Anisotropy: indicator of microstructural changes and reduced connectivity Increased Apparent Diffusion Coefficient: associated with nerve atrophy

15 Treatment Medical treatment is first line Surgical interventions (including SRS) for refractory cases up to 50% of patients with classic TN will eventually require surgery

16 Medical Therapy Interrupt the temporal summation of afferent impulses After breakthrough on a single agent, a second and even third medication may be required Anticonvulsant medicines carbamazepine (most effective), oxcarbazepine, topiramate, clonazepam, phenytoin, lamotrigine, and valproic acid. many adverse CNS side effects up to 44% relapse or have unsatisfactory relief Gabapentin or baclofen Tricyclic antidepressants used to treat pain described as constant, burning, or aching Opiates are typically not helpful Dalessio DJ. Trigeminal neuralgia. A practical approach to treatment. Drugs. Sep 1982;24(3):

17 Surgical Management of Facial Pain

18 Classification of Facial Pain

19 Classification of Facial Pain

20 Trigeminal Neuralgia Diagnostic Questionnaire

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22 Facial Pain Treatment Algorithm

23 Trigeminal Tract Neuroanatomy -Semilunar Ganglion -Gasserian Ganglion -Gasser s Ganglion -Trigeminal Ganglion

24 Trigeminal Tract Neuroanatomy VPM

25 Trigeminal Tract Neuroanatomy

26 Peripheral Trigeminal Nerve Interventions V3 block V2 block Peripheral nerve blockade

27 Peripheral Trigeminal Nerve Interventions Supraorbital Infraorbital Inferior Alveolar Neurectomy

28 Peripheral Trigeminal Nerve Interventions Peripheral Neurostimulation

29 Interventions at the Ganglion Percutaneous Radiofrequency Trigeminal Gangliolysis

30 Interventions at the Ganglion Balloon Compression and Glycerol Rhizolysis

31 Interventions at the Ganglion Gasserian Stimulation

32 Dorsal Root Entry Zone Microvascular Decompression

33 Dorsal Root Entry Zone Trigeminal Rhizotomy

34 Trigeminothalamic Tract -Trigeminal Tractotomy -Nucleus Caudalis DREZ

35 Trigeminothalamic Tract High Cervical Spinal Cord Stimulation

36 Thalamus Deep Brain Stimulation

37 Cortex

38 Temporary Trials

39 Absence of surgical risk Targets focused beams of high dose radiation to the trigeminal nerve at exit from the brainstem Axonal degeneration and necrosis disrupt transmission of pain signals Single treatment: maximum dose of 70 to 90 Gy Average pain-free is about the same as for radiofrequency (RF) rhizotomy, or around 3 years Stereotactic Radiosurgery

40 Delineate the retrogasserian sensory root of the prepontine TN 1) anatomy tends to be symmetric. 2) Find the trigeminal eminence 3) Find Meckel s cave 4) trigeminal sensory root will travel between brainstem and Meckel s cave 5) Reference the coronal and sagittal images 6) target volume encompassed by 2 to 3, two mm thick MR slices

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42 Gammaknife

43 Cyberknife Frameless SRS

44 initial pain relief in up to 90% of cases, lag time ranging from 1 to 3 months. side effects: facial numbness, ranging from 20% to 32%, and less commonly dysesthesias and weakness One of the challenges of SRS is the long-term durability of pain relief

45 Of 59 studies, 41 reported on SRS (n =5242), 12 reported on MVD (n= 8028), and 5 reported on both SRS (n = 535) and MVD (n =237). Efficacy In the group treated with SRS, the initial success rate was 71.1%. Success rates at follow-up (2 years, between years 2 and 5, and after 5 years) amounted to 77.8%, 63.1%, and 63.8%, respectively. In the group treated with MVD, the initial success rate was 86.9%. At followup, success rates were 91.4% (2 years), 80.6% (between years 2 and 5), and 84% (>5 years), respectively. With a median follow-up time of 36 months, the median recurrence rate was 11% for MVD and 25% for SRS, respectively

46 Complications less frequent complications: MVD: perioperative mortality (0.31%), cerebrospinal fluid leak (2.73%), and the combined percentage of cerebrovascular, cardiologic, pneumologic, or thromboembolic events (3.92%) in MVD. SRS: Keratitis, Anesthesia dolorosa (0.04%), tinnitus (0.15%), brainstem edema (0.06%), and chronic fatigue (0.79%)

47 Conclusions MVD yields more immediate and better long-term relief Although surgical complications associated with MVD are not negligible, dysesthesia and other CN effects after SRS may significantly compromise the patient s quality of life too. MVD is a valid first-line treatment option for patients free of comorbidities. SRS would be advised in patients with a high surgical and anesthetic risk.

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50 Questions?