Corticomotoneuronal integrity and adaptation in spinal muscular atrophy.

نویسندگان

  • Michelle A Farrar
  • Steve Vucic
  • Heather M Johnston
  • Matthew C Kiernan
چکیده

OBJECTIVE To gain further insight into disease pathophysiologic process and potential adaptations through investigating whether cortical dysfunction or plasticity is a feature of spinal muscle atrophy (SMA). DESIGN Prospective, double-center study. SETTING Outpatient clinics and research institute. PARTICIPANTS Clinical assessments, combined with threshold-tracking transcranial magnetic stimulation techniques, were completed in 11 genetically characterized patients with SMA. MAIN OUTCOME MEASURES Clinical, functional, and neurophysiologic variables were compared between the 11 patients with SMA types 2 and 3, 24 healthy control participants, and 81 patients with amyotrophic lateral sclerosis (ALS) serving as disease controls. RESULTS Maximal motor-evoked potential amplitude as a percentage of the compound muscle action potential was significantly increased in patients with SMA compared with the healthy controls but was similar to that in ALS (SMA, mean [SE], 39.7% [4.0%]; ALS, 38.8% [2.8%]; controls, 20.3% [2.5%]; F = 10.1; P < .001). In contrast, short-interval intracortical inhibition (SMA, 14.4% [1.6%]; ALS, 4.3% [1.8%]; controls, 17.0% [2.3%]; F = 11.4; P < .001) and cortical silent-period duration (SMA, 204.4 [9.8] milliseconds; ALS, 182.7 [5.2] milliseconds; controls, 208.8 [3.7] milliseconds; F = 4.8; P = .01), similar between SMA patients and healthy controls, were significantly larger when compared with the findings in ALS. Of relevance, peripheral disease burden as measured by the compound muscle action potential amplitude (SMA, 6.3 [0.8] mV; ALS, 5.9 [0.4] mV; controls, 11.8 [0.5] mV; F = 35.5; P < .001) and Neurophysiological Index (SMA, 0.7 [0.2]; ALS, 0.7 [0.1]; controls, 3.1 [0.2]; F = 108.2; P < .001), were significantly reduced in both SMA and ALS patients when compared with healthy controls. CONCLUSIONS Taken together, findings from the present study suggest that despite spinal motoneuron degeneration there remains preservation of corticomotoneuronal function in SMA. The greater corticomotoneuronal projections to surviving spinal motoneurons likely represent an adaptive response to spinal motoneuron degeneration in SMA.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Spinal Muscular Atrophy: A Short Review Article

Spinal muscular atrophy (SMA) is a genetic disorder which affect nervous system and is characterized with progressive distal motor neuron weakness. The survival motor neuron (SMN) protein level reduces in patients with SMA. Two different genes code survival motor neuron protein in human genome. Skeletal and intercostal muscles denervation lead to weakness, hypotony, hyporeflexia, respiratory fa...

متن کامل

Drawing Word co-occurrence map of Spinal Muscular Atrophy disease

Introduction:  The purpose of this article is to evaluate the status of articles in the field of Spinal Muscular Atrophy According to the Scientometrics indices Word co-occurrence map of this field . Methods: The present study is an applied one with a quantitative approach and a descriptive approach. It has been done using scientometrics and the co-occurrence words analysis technique. Document...

متن کامل

A Patient with Tuberous Sclerosis Complex and Spinal Muscular Atrophy; A Case Report

Background Tuberous Sclerosis Complex (TSC), and Spinal Muscular Atrophy (SMA) are two inherited disorders while they are genetically independent. TSC is characterized by the formation of multiple hamartomas in nearly all organs. SMA is a destructive neurological disorder leading to progressive muscular weakness and atrophy. Case Presentation</e...

متن کامل

O-27: Preimplantation Genetic Diagnosis in Prevention of Genetic Diseases -Diagnostic of Spinal Muscular Atrophy (SMA)

Background: Preimplantation genetic diagnosis - PGD is currently an established procedure allowing genetic research of oocyte or embryo before implantation to the uterus. Spinal muscular atrophy (SMA) is a neurodegenerative disorder, being the second most common lethal autosomal recessive disease in Caucasians, after cystic fibrosis. There are three clinically different types of which type I (W...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Archives of neurology

دوره 69 4  شماره 

صفحات  -

تاریخ انتشار 2012