The diagnosis of myathenia gravis in cases presenting only with mild ptosis and ophalmoplegia or only with occasional diplopia is difficult. It has been known for years that extraocular muscle tension influences intraocular pressure in a considerable way. Using short rapid acting intravenous injection of Tensilon combined with tonogram, the recovery of ocular muscle power can easily be observed from the elevation of intraocular pressure shown in the tonogram. The preliminary experiments on three cases of ocular myathenia graivs reveal this Tensilon tonogram has great help in the diagnosis of early cases.