PT - JOURNAL ARTICLE AU - D G Podikoglou AU - T G Avramidis AU - A L Papadimitriou TI - Blink reflex in primary lateral sclerosis AID - 10.1136/jnnp.2003.017954 DP - 2004 Jul 01 TA - Journal of Neurology, Neurosurgery & Psychiatry PG - 1064--1065 VI - 75 IP - 7 4099 - http://jnnp.bmj.com/content/75/7/1064.short 4100 - http://jnnp.bmj.com/content/75/7/1064.full SO - J Neurol Neurosurg Psychiatry2004 Jul 01; 75 AB - Objective: To investigate the underlying pathophysiology of primary lateral sclerosis (PLS) regarding possible changes in blink reflex (BR) circuit. Methods: BR was studied in 10 patients in whom diagnosis of PLS was established by comparing them to two control groups: ten patients with amyotrophic lateral sclerosis (ALS) and 30 healthy volunteers. All patients were followed up annually for a 5 year period. A typical evoked potential study of the BR was employed. Results: Significantly lower values of R2 and R2′ amplitude were found both in the PLS and ALS groups compared with the healthy control group. All these differences were highly significant (p<0.001). R1 amplitude and latency, as well as R2 and R2′ latencies, were normal in all patients. Annually recorded follow up data revealed no significant changes in BR values for PLS patients. In contrast, for ALS patients, BR progressively disappeared following clinical impairment. Conclusions: The study suggests that BR is abnormal in PLS. It also adds some clues regarding PLS pathophysiology and can be helpful as a marker of ALS progression.