Melih TÜTÜNCÜ, Hikmat ABBASZADE, Ayşegül GÜNDÜZ, Meral E. KIZILTAN

Peripheral Silent Period In Cervical and Generalized Dystonia

Objective: Dystonia is a movement disorder described by continuous or alternating muscle contractions causing unusual postures or insistent motions. Abnormal sensorimotor integration and abnormalities in inhibitory pathways are thought to have a role in pathogenesis. This paper aims to research the state of inhibitory pathways in the spinal cord in dystonia through documenting a silent period (SP) through cutaneous stimulation (CuSP) or mixed nerve stimulation (MnSP). Methods: 23 patients with dystonia were included in the study. Also, 19 healthy subjects were included in the study as a control group. Ages were similar between two groups. (p=0.092). CuSP and MnSP are recorded through abductor pollicis brevis and median nerve at the wrist respectively. Results: Onset latency, time, and suppression index of CuSP were equivalent between two groups. Moreover, the initiation and terminate latencies of MnSP, also duration, were similar between these two groups. I2 suppression index was lower in generalized dystonia patients compared to patients with cervical dystonia (100.0 vs 86.7±21.4%; F=4.252, 0.035). Conclusions: The most striking result to emerge from the data is that there was lower suppression during CuSP in generalized dystonia patients. Our results suggest that spinal inhibitory circuits are less active if only there is clinical involvement of the relevant segment.

Servikal ve Jeneralize Distonide Periferik Sessiz Periyot

Amaç: Distoni, sürekli veya aralıklı kas kasılmalarının anormal duruşlara veya tekrarlayan hareketlere neden olduğu istemsiz bir hareket bozukluğudur. Distoni sadece bir motor sistem hastalığı değildir. Patofizyolojisinde, anormal sensorimotor entegrasyon yaygın olarak kabul edilmektedir. Diğer bir patofizyolojik açıklama, inhibitör yolaklardaki anormalliklerdir. Bu çalışmanın amacı, kutanöz stimülasyonu (CuSP) veya miks sinir stimülasyonunu (MnSP) takiben sessiz period (SP) kaydederek distonide, omurilikteki inhibitör yolakların durumunu araştırmaktır. Yöntemler: Çalışmaya 23 distonili hasta dahil edildi. Ayrıca kontrol grubu olarak 19 sağlıklı denek mevcuttu. Yaş gruplar arasında benzerdi. (p = 0.092). CuSP ve MnSP, sırasıyla abdüktör pollicis brevis ve median sinir aracılığıyla kaydedildi. Bulgular: CuSP'nin başlangıç latansı, süresi ve supresyon indeksi ile ilgili olarak, distoni hastaları ile sağlıklı bireyler arasında fark yoktu. MnSP'nin başlangıç ve bitiş latansları ayrıca süreleri, hastalar ve sağlıklı bireyler arasında farklı değildi. Segmental ve jeneralize distonili hastaların karşılaştırılması, jeneralize distoni hastalarında I2 supresyon indeksinin düşük olduğunu gösterdi (100.0'a karşı 86.7 ± 21.4%; F = 4.252, 0.035). Tartışma: Jeneralize distonili hastalarda CuSP sırasında daha az supresyon görülürken, servikal distonili hastalarda sağlıklı deneklere benzerdi. Sonuçlarımız, spinal inhibitör devrelerin, sadece ilgili segmentin klinik tutulumu varsa daha az aktif olduğunu.

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