EVALUATION OF REPETITIVE NERVE STIMULATION WITH DIFFERENT STIMULATION FREQUENCIES IN PATIENTS WITH MYASTHENIA GRAVIS

Year 2020, Volume: 83 Issue: 3, 197 - 203, 29.06.2020

Nermin Görkem Şirin Elif Kocasoy Orhan Elif Oğuz Akarsu Hacer Durmuş Feza Deymeer Mehmet Barış Baslo

Abstract

Objective: To investigate the effect of voluntary contraction at low frequency repetitive nerve stimulation (RNS) as a sign of presynaptic compensation in patients with Myasthenia Gravis (MG). Material and Method: Thirty-five patients with MG were included. RNS at 3 Hz, recorded from the abductor digiti minimi, trapezius, nasalis, and orbicularis oculi muscles were performed. In muscles with more than 10% decrement, RNS at 1 Hz with 20-90 stimuli was applied after 10-second maximal isometric voluntary muscle contraction (MIVMC). Progressive decremental pattern was considered when decrement values were increasing until the last response. Facilitation after MIVMC was determined by dividing the amplitude of motor response in resting state by the amplitude of the motor response recorded just after contraction. Results: Among 15 patients having RNS at 1 Hz, nine had facilitation after MIVMC. In the muscle with facilitation, there was a significant positive correlation between the increment ratio and the progressive decrement difference between responses 1-4 and 1-9 (correlation coefficient 0.730, p=0.026). Although not statistically significant, muscles showing facilitation following decrement tended to have a progressive decremental pattern. Conclusion: During RNS, facilitation after MIVMC followed by progressive decremental pattern may be related to presynaptic compensation of neuromuscular transmission failure in MG.

Keywords

., ,, ;

MYASTHENİA GRAVİS HASTALARINDA FARKLI UYARI FREKANSLARI İLE ARDIŞIK SİNİR UYARIM TESTİNİN İNCELENMESİ

Abstract

Amaç: Bu çalışmada, Myasthenia Gravis (MG) hastalarında presinaptik kompansasyonun bir göstergesi olarak maksimal istemli kası sonrasında ardışık sinir uyarım testinde (ASU) değişikliklerin incelenmesi amaçlandı. Gereç ve Yöntem: Otuz beş MG hastası çalışmaya dahil edildi. Bu hastalara abdüktör digiti minimi, trapez, nazalis ve orbikülaris okuli olmak üzere 4 kastan 3 Hz ASU incelemesi yapıldı. Dekrement oranı %10 üzerinde olan kaslarda 10 saniye izometrik maksimal kası sonrasında 1 Hz ASU incelemesi tekrarlandı. Bu kaslarda kası sonrası fasilitasyon ve progresif dekrement paterni varlığı değerlendirildi. Progresif dekrement paterni, ASU incelemesinde dekrement oranının son uyarıya kadar artması olarak belirlendi. Progresif dekrement farkı ise 1-4 ve 1-9 ile 1-4 ve 1-son uyarı ile kaydedilen dekrement değerlerinin birbirinden çıkartılması ile hesaplandı. Fasilitasyon ise kası sonrası ve istirahatte kaydedilen motor yanıt amplitüdlerinin birbirine oranlanması ile belirlendi. Bulgular: İstemli kası sonrası 1 Hz ASU yapılan 15 hastanın 9’unda fasilitasyon saptandı. Fasilitasyon izlenen kaslarda inkrement oranı ile progresif dekremet farkı (1-4 ve 1-9 uyarı arası) istatistiksel olarak anlamlı pozitif bir korelasyon gösterdi (korelasyon katsayısı 0,730; p=0,026). İstatistiksel olarak anlamlı olmamakla birlikte ilk 9 uyarıda progresif dekrement paterni varlığı dekrementi takiben fasilitasyon izlenen kaslarda daha fazlaydı. Sonuç: İzometrik kası sonrasında düşük frekanslı ASU incelemesi MG hastalarında presinaptik kompansasyonu gösterebilir.

References

• 1. Jaretzki A, 3rd, Barohn RJ, Ernstoff RM, Kaminski HJ, Keesey JC, Penn AS, et al. Myasthenia gravis: recommendations for clinical research standards. Task Force of the Medical Scientific Advisory Board of the Myasthenia Gravis Foundation of America. Ann Thorac Surg 2000;70(1):327-34. [CrossRef]
• 2. Stalberg E. Clinical electrophysiology in myasthenia gravis. J Neurol Neurosurg Psychiatry 1980;43(7):622-33. [CrossRef]
• 3. Oh SJ, Morgan MB, Lu L, Hatanaka Y, Hemmi S, Young A, et al. Different characteristic phenotypes according to antibody in myasthenia gravis. J Clin Neuromuscul Dis 2012;14(2):57-65. [CrossRef]
• 4. Farmakidis C, Pasnoor M, Dimachkie MM, Barohn RJ. Treatment of Myasthenia Gravis. Neurol Clin 2018;36(2):31137. [CrossRef]
• 5. Benatar M. A systematic review of diagnostic studies in myasthenia gravis. Neuromuscul Disord 2006;16(7):459-67. [CrossRef]
• 6. Kelly JJ, Jr., Daube JR, Lennon VA, Howard FM, Jr., Younge BR. The laboratory diagnosis of mild myasthenia gravis. Ann Neurol 1982;12(3):238-42. [CrossRef]
• 7. Oh SJ, Kim DE, Kuruoglu R, Bradley RJ, Dwyer D. Diagnostic sensitivity of the laboratory tests in myasthenia gravis. Muscle Nerve 1992;15(6):720-4. [CrossRef]
• 8. Medicine AQACAAoE. Practice parameter for repetitive nerve stimulation and single fiber EMG evaluation of adults with suspected myasthenia gravis or Lambert-Eaton myasthenic syndrome: summary statement. Muscle Nerve 2001;24(9):1236-8. [CrossRef]
• 9. Benatar M, Sanders DB, Burns TM, Cutter GR, Guptill JT, Baggi F, et al. Recommendations for myasthenia gravis clinical trials. Muscle Nerve 2012;45(6):909-17. [CrossRef]
• 10. Oh SJ, Kurokawa K, Claussen GC, Ryan HF, Jr. Electrophysiological diagnostic criteria of Lambert-Eaton myasthenic syndrome. Muscle Nerve 2005;32(4):515-20. [CrossRef]
• 11. Ozdemir C, Young RR. Electrical testing in myasthenia gravis. Ann N Y Acad Sci 1971;183287-302. [CrossRef]
• 12. Baslo MB, Deymeer F, Serdaroglu P, Parman Y, Ozdemir C, Cuttini M. Decrement pattern in Lambert-Eaton myasthenic syndrome is different from myasthenia gravis. Neuromuscul Disord 2006;16(7):454-8. [CrossRef]
• 13. Sanders DB, Cao L, Massey JM, Juel VC, Hobson-Webb L, Guptill JT. Is the decremental pattern in Lambert-Eaton syndrome different from that in myasthenia gravis? Clin Neurophysiol 2014;125(6):1274-7. [CrossRef]
• 14. Sirin NG, Kocasoy Orhan E, Durmus H, Oflazer P, Parman Y, Oge AE, Deymeer F, Baslo MB. Jitter Measurement using a Concentric Needle in 133 Patients with Myasthenia Gravis: A Retrospective Analysis. J Neurol Sci-Turk 2017;34(3):20714. [CrossRef]
• 15. Burns TM, Conaway MR, Cutter GR, Sanders DB, Muscle Study G. Construction of an efficient evaluative instrument for myasthenia gravis: the MG composite. Muscle Nerve 2008;38(6):1553-62. [CrossRef]
• 16. Sirin NG, Kocasoy Orhan E, Durmus H, Deymeer F, Baslo MB. Repetitive nerve stimulation and jitter measurement with disposable concentric needle electrode in newly diagnosed myasthenia gravis patients. Neurophysiol Clin 2018;48(5):261-7. [CrossRef]
• 17. Oh SJ, Nagai T, Kizilay F, Kurt S. One-minute exercise is best for evaluation of postexercise exhaustion in myasthenia gravis. Muscle Nerve 2014;50(3):413-6. [CrossRef]
• 18. Sanders DB, Stalberg EV. AAEM minimonograph #25: single-fiber electromyography. Muscle Nerve 1996;19(9): 1069-83. [CrossRef]
• 19. Sanders DB, Howard JF, Jr. AAEE minimonograph #25: Single-fiber electromyography in myasthenia gravis. Muscle Nerve 1986;9(9):809-19. [CrossRef]
• 20. Oh SJ, Eslami N, Nishihira T, Sarala PK, Kuba T, Elmore RS, et al. Electrophysiological and clinical correlation in myasthenia gravis. Ann Neurol 1982;12(4):348-54. [CrossRef]
• 21. Luigetti M, Modoni A, Lo Monaco M. Low rate repetitive nerve stimulation in Lambert-Eaton myasthenic syndrome: peculiar characteristics of decremental pattern from a singlecentre experience. Clin Neurophysiol 2013;124(4):825-6. [CrossRef]