The cerebellum is known to be very important for the maintenance of body balance or of smooth eye movements. Eye movements consist of two factors, that is saccade and pursuit, which are examined using the stimuli of saw-toothed waves. A round target of 1 cm in diameter moves from the right to the left side with a visual angle of 30° for the period of 3 sec and it moves back to the right side immediately after the target has reached to the left side. This reversed stimulus is also used. The saccade and pursuit eye movements were evoked in the examinees who followed the traget movements, which were recorded by an electronystagmography (ENG). The eye velocity of saccade and the latency between the initiation of the target and that of eye movements were measured. Horizontal eye movements, saccade and pursuit were studied.The numbers of small saccadic eye movements during the pursuit eye movements were measured. In 20 normal adults, the eye velocity of saccade was 169±19°/sec, the latency 0.15 ±0.05 sec and the small saccadic eye movements 0-1 beats/cycle during the pursuit eye movements.In 27 cerebellar lesions, the eye velocity of saccade was within normal limits, the latency prolonged and the pursuit eye movements strongly impaired. That is, the pursuit eye movements seem to be closely related with the cerebellum.
Eye movements have two factors, that is, quick components or saccades and slow components or pursuit eye movements. A study has been made of whether visual fixation is concerned with saccades or pursuit eye movements.Visual fixation has been examined by the visual suppression test. The eye-tracking test is one of the methods for examining visual fixation, although it evaluates pursuit eye movements. Visual suppression is concerned with both saccades and pursuit eye movements.Visual fixation is composed of two factors, that is, quick eye movements or saccades and slow eye movements or pursuit eye movents.
The magnetic resonance (MR) images of the temporal bones have been analyzed, these MR images taken with head coils utilizing a 1.5-Tesla magnet whole-body imaging system. The MR images were acquired by means of spin-echo pulse sequences, and the thickness of the sections was 2.5 mm. By this modality, the T2-weighted images could clearly delineate the details of the liquid-containing labyrinthine structures and facial nerve. MR imaging can provide information that is unobtainable from a CT scan in the diagnosis of inner ear disorders, particularly as to whether the membranous labyrinth is filled with the lymph fluid or is flbrosed. This point is one of the greatest advantages of MR imaging over a high-resolution CT scan.After the dramatic advances of X-ray-computerized tomography it seems that since 5 years the next step of this evolution has begun with the development of magnetic resonance imaging for clinical diagnosis.
12 cases of unilateral labyrinthectomy, 3 cases of VIIIth nerve section, 22 cases of streptomycin sulfate infusion into the middle ear cavity and 8 cases of bilateral vestibular a-functions underwent vestibular training. Our training is very useful for regaining equilibrium and for evaluating the effects of training on equilibrium by recording the gravity center movements.
IN 1904, Albrecht1defined hamartoma as a tumor-like malformation in which normal tissue components of the organ are abnormally arranged, varying in size and differentiation of tissues. The liver, spleen, kidney, and lung are frequent sites. However, hamartoma is seldom found in the tongue. We recently experienced a case of lingual hamartoma which was successfully removed. This is a brief report of the case.
Report of a Case
The patient, a 4-month-old girl, was brought to our clinic. The mother noticed four round, gray-white masses in the tongue one month after birth. The patient was born prematurely as a fraternal twin. According to her mother's impression, the baby seemed to have slight difficulty in nursing. Examination of the oral cavity revealed four smoothly surfaced, gray-white hard tumor-like masses in the lingual area (Fig 1). The largest, 1 × 1 × 3 cm was located at the lingual base of the
