Trigeminal neuralgia

Trigeminal Neuralgia, consized

1. Trigeminal neuralgia Dr Dikpal

2. ANATOMY

3. History 2 nd Century : Aretaeus , account of TN 1756 : Nicolas Andre, Tic Douloureux 1773: Forthergill , Clinical Features 1820: Charles Bell, Cause 1932: Walter Dandy, MVD 1970 : NAP were gold std 1967: Janetta reintroduced MVD

4. Clinical Features Site: Divisional, Unilateral Character: sharp, shooting, unbearable, arresting Timing: seconds- min. , no after pain Provoking: light touch Relieving: Sleep, Drugs Diurnal : More in morning

5. Burchiel`s Classification TN type 1 : >50 % episodic pain (Spontaneous) TN type 2 : > 50% constant pain TG neuropathic pain: unintentional trauma TG Deafferentation pain: intentional deafferention Symptomatic TGN: MS / Tumour Post Herpetic Neuralgia: HZ outbreak Atypical Facial Pain: somatoform pain disorder

6. Pathophysiology Pulsatile mechanical trauma Obersteiner - Redlich Zone Ectopic action potential Spontaneous / triggered after discharge Cross excitation from neighbouring afferent fibre Elongation of cisternal arteries with age : disease of elderly

7. Differential Diagnosis Dental MS Atypical TN TM joint Pathology Postherpetic Neuralgia Cluster Headache

8. Investigation Clinical diagnosis Support Diagnosis: MRI Structural lesions ( cavernoma , schwanomma , meningioma ) Vascular loops White Matter Lesions CISS (constructive interference in steady state ) BERA / PTA

9. Treatment

10. Medical Carbamazepine : (CBC, Sr Na, LFT, ) Oxcarbamazepine Baclofen Gabapentin Eptoin

11. Surgery Failure / partial relief with medication after 1 year > 3000 tablets of single drug Drugs toxicity Patient preference

12. Percutaneous ablative Elderly MS Pontine infarction White matter lesion w/o MS Previously failed MVD

13. Radiofrequency Ablation Alternating electric field, heat Hartel technique Supine , head extended 30 degree Lesion : 75-80 degree C for 90 sec End point : hypoaesthesia BEST among percutaneous

14. Glycerol Rhizotomy 20 G , 3.5 Inch Spinal Needle Sitting position Selective neurolysis : floating glycerol technique Contact time : atleast 1 hour

15. Balloon Compression Supine with head extended 15 degree 14 G blunt obturator No. 4 Fogarty Intraluminal pressure 1200 – 1500 mmHg (1-1.5atm) {tissue: 650-950 mmHg} Compression time less than 2 mins

16. Post operative management Corneal sensation Jaw opening exercises, soft diet Meningitis (Glycerol vs infective) COMPLICATION Dysesthesia (RF) Corneal hypoesthesia (glycerol) Masseter weakness (balloon) Stroke , hemorrhage, pseudomeningocele , CN weakness

17. Radiosurgery MOA: Axonal degeneration by radiation : presumed Arteriolar thickening of vessel in contact More effective as initial modality Target : Root entry zone Dose : 70-90 Gy Recurrence : delivery at anterior to previous site Cumulative dose < 140 Gy Approx 4-6 weeks for pain relief High recurrence

18. MVD Indication Contraindication : unfit, elderly , MS

19. Steps Lateral position Retro sigmoid craniotomy Cerebellum retracted inferiorly and medially Preserve veins , arteries Inspect V nerve Teflon / muscle / dacron / gelfoam No compression : gentle manipulation / section at antero inferior aspect

20. Complication Mortality < 0.5% Facial weakness, hearing loss Recurrence female venous compression failure of immediate pain relief > 8 yrs symptoms

21. Special cases Multiple sclerosis Balloon compression is the best Recurrent Cases MVD recurrence Glycerol recurrence SRS recurrence

22. Thanks