抄録
The causes of MLF syndrome are generally considered to be vascular lesion, tumor, multiple sclerosis and head trauma. In clinical practice we often encounter such cases, where neurotological examination is important for the diagnosis of MLF syndrome.
It is well known that MLF plays an important role in the system of vestibulo-ocular reflex. For instance, clear electrical potential can be obtained from MLF during the electrical stimulation of individual vestibular nerve branches. Such anatomical and physiological data are shown in this paper.
On the other hand, when MLF is stimulated electrically in monkey at the level between trochlear and abducens nucleus, only the ipsilateral eye adducts. Furthermore, when electrical lesion is made in MLF, the ipsilateral eye cannot adduct. In clinical cases, MLF syndrome presents the following signs, as described by M. B. Bender.:
1) paralysis of ipsilateral ocular adduction.
2) nystagmus in the abducted eye during horizontal gaze.
3) preservation of convergence.
In this paper, two clinical cases are presented, which showed typical MLF syndrome. The first case was suspectedly due to vascular lesion and the second case occurred after head trauma. For diagnosis of MLF syndrome, neuro-otological examination, especially the test of eye movement, is essential. So it is emphasized that the fundamental knowledge of MLF syndrome is important for otologists.
