Abstract
A 48-year-old female suffered from severe nausea and vomitting for one week before the admission. She showed signs as follows;
1) Spontaneous vertical nystagmus appeared upon gaze upward and horizontal nystagmus appeared upon gaze to right and left. 2) Directional preponderance to right was shown by caloric test. 3) Left and downward optokinetic nystagmus was not observed when the stimulations were given. 4) Severe ataxia was shown. The patient could not keep Romberg's posture even with open eyes. 5) Dysdiadochokinesis was found in her right arm. 6) Paresis of abduction of left eye ball, left facial paresis and left trigeminal paresis were seen. 7) Spinal fluid, ophthalmoscopic finding and the internal auditory meatus were normal.
As a treatment, intravenous injection of Théraptique was performed for-one month. All symptoms were mended after four months from the onset.
Incomplete obstruction of the left anterior inferior cerebellar artery by thrombus is suspected as pathogenesis of this case, because the limit of cerebral nerves which became paretic showed the region of this artery. However, the labyrinthine artery is commonly a branch of the anterior inferior cerebellar artery, and it is contradictory that the patient showed almost normal labyrinthine function. The hearing of the patient was in normal level. The vestibular signs did not occur from the vestibule but from the vestibular nuclei.
We think that the left labyrinthine artery of this patient did not branched from the anterior inferior cerebellar artery but from the posterior inferior cerebellar artery or one of double branches of the anterior inferior cerebellar artery. According to the anatomical investigations, it is said that such a case is not so rare.