Göksemin ACAR, Levent Sinan BİR, Eylem DEĞİRMENCİ, Selahattin GÜR

Evaluation of motor nerve excitability by subtreshold stimuli in diabetic polyneuropathy

Özet Amaç: Bu çalışmanın amacı diabetik polinöropatide motor sinir uyarılabilirliğini incelemektir. Gereç ve yöntem: Çalışmaya 45 hasta alınarak 3 gruba ayrıldı (Grup I: polinöropatisi olmayan diabetik hastalar, Grup II: polinöropatisi olan diabetik hastalar, Grup III: sağlıklı kontroller). Tibial sinir 100μs süreyle 5mAden başlayıp 5er mAlik artışlarla maksimum 100mA e kadar uyarıldı. Her bir uyarı şiddetiyle ortaya çıkan bileşik kas aksiyon potansiyel (BKAP) amplitüdü, elde edilen maksimum BKAP amplitüdüne bölünerek her bir uyarı şiddetiyle rekrüte olan motor ünit oranı hesaplandı. Hesaplanan bu değer gruplar arasında karşılaştırıldı. Bulgular: Polinöropatisi olmayan diabetik hastalarla polinöropatisi olan diabetik hastalar arasında eşikaltı uyaranlarla motor sinir uyarılabilirliği arasında anlamlı bir fark saptanmadı.   Sonuç: Bu bulgularla, eşik altı uyarıların giderek artan serilerde uygulanmasının diabetik hastalardaki motor sinir hasarı ile ilgili ek bir bilgi sağlamadığı sonucuna varıldı. 

Diabetik polinöropatide eşik altı uyarilarla motor sinir eksitabilitesinin değerlendirilmesi

Abstract Purpose: The aim of this study is to evaluate motor nerve excitability in diabetic polyneuropathy. Materials and methods: Forty-five patients were enrolled and divided into 3 groups (Group I; diabetic patients without polyneuropathy, Group II; diabetic patients with polyneuropathy, Group III; healthy controls,). The stimuli were given to tibial nerve for 100μs with 5 mA increments starting from 5 mA up to the maximum of 100mA. The CMAP amplitudes appearing with each current of stimulus were divided into the maximum CMAP amplitude for each patient. This value is considered as the ratio of recruited motor units (RRMU) for that current. The mean value of the RRMU for each stimulus current in groups II and III were compared with the healthy controls. Results: The statistical analysis revealed no significant difference in diabetic patients in terms of nerve excitability with the subtreshold stimuli. Besides, the current that is needed to achieve the maximum CMAP amplitude did not differ between the groups. Conclusion: Giving subtreshold stimuli with increasing currents did not give additional information about motor nerve impairment in diabetic patients.

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