Humans ; Neurons ; Olivary Nucleus ; Superior Olivary Complex

Hypertrophic olivary degeneration (HOD) is regarded as a secondary degenerative change subsequent to the formation of lesions in the "Guillain-Mollaret Triangle," and this is the result of the loss of transsynaptic neurologic input to the inferior olivary nucleus. HOD usually occurs unilaterally, but bilateral hypertrophic olivary degeneration is known to be rare. We experienced one case of this lesion, and we report here on the bilateral HOD that was secondary to infarction of the brainstem and cerebellum.
Brain Stem* ; Cerebellum* ; Infarction* ; Olivary Nucleus*

OBJECTIVETo investigate the distribution and projective feature of cat olivocochlear neurons.

METHODSEleven adult cats were divided into two groups randomly. The experimental group of eight cats was injected of 1% cholera toxin B (CTB) to the left cochlea, while injected of 5% fluoro gold (FG) to the right cochlea. The control group of three cats was injected of saline to bilateral cochlea. After a survival time of 7 days, serial frozen sections were cut in the cat brainstem. All the sections were processed by immunofluorescent procedure for CTB and FG, and the labeled olivocochlear neurons were observed by fluorescent microscope.

RESULTSIn the experimental group, the mean total of olivocochlear neurons labeled by CTB and FG was 3210 +/- 168, including lateral olivocochlear neurons (LOC, 2298 +/- 120) and medial olivocochlear neurons (MOC, 913 +/- 64). The labeled neurons were divided into three different types according to their feature of projection: neurons which only projected to the ipsilateral cochlea, neurons which only projected to the contralateral cochlea, and double-labeled neurons which projected both to the ipsilateral and contralateral cochlea, but the double-labeled neurons comprised 3.9% and 15.1% in the LOC and MOC system respectively. No labeled neurons were found in the control group.

CONCLUSIONSThere are three types of neurons in the cat olivocochlear system. The neurons which projected to the bilateral cochlea may distribute both in the LOC and MOC system.

Animals ; Auditory Pathways ; Biomarkers ; Cats ; Cochlear Nucleus ; anatomy & histology ; Fluorescent Dyes ; Neurons ; physiology ; Olivary Nucleus ; physiology

Holmes' tremor is a condition characterized by a mixture of postural, rest, and action tremors due to midbrain lesions in the vicinity of the red nucleus. Hypertrophic olivary degeneration (HOD) is a rare type of neuronal degeneration involving the dento-rubro-olivary pathway and may present clinically as Holmes tremor. We report on a 59-year-old female patient who developed Holmes tremor in association with bilateral HOD, following brain stem hemorrhage.
Brain Stem* ; Female ; Hemorrhage* ; Humans ; Mesencephalon ; Middle Aged ; Neurons ; Olivary Nucleus ; Red Nucleus ; Tremor*

OBJECTIVE: The purpose of the study is to draw the three-dimensional reconstructions of nuclei and tracts of the auditory pathway structures of drainstem. METHOD: The drawings of 1 mm sections of the brainstem were scanned with a computer scanner into AUTOCAD program. All lines of structures except for the auditory pathway structures and outlines were removed. Each layer was plotted to a x, y, and z coordinated plotting reference to the corresponding points on the mid-sagittal plane and reconstructed to a three-dimensional drawing. Center point of the auditory pathway structures of all cross section layers were connected with a line in succession and that was thought to be a imaginary pathway of auditory pathway through the brainstem. RESULTS: This auditory pathway has several turning points, at the cochlear nucleus, superior olivary nucleus, and inferior colliculus which correspond with known generation sources of the peak of brainstem evoked potentials. CONCLUSION: This study presents a method for the conversion of the two-dimensional transverse sections into a three-dimensional format, to allow the visualization of the auditory pathway structures from multiple directions.
Auditory Pathways* ; Brain Stem* ; Cochlear Nucleus ; Evoked Potentials ; Inferior Colliculi ; Olivary Nucleus

The dorsolateral medullary syndrome (Wallenberg's syndrome) is produced by infarction of a wedge of lateral medulla posterior to the inferior olivary nucleus, and is usually caused by vertebral artery occlusion. Ipsilateral axial lateropulsion as an initial symptom of vertebral artery occlusion is rare, and the responsible anatomical structure is still uncertain. Here we describe a patient presenting with ipsilateral axial lateropulsion as an initial symptom of vertebral artery occlusion.
Humans ; Infarction* ; Lateral Medullary Syndrome ; Magnetic Resonance Imaging ; Olivary Nucleus ; Vertebral Artery

BACKGROUND: Oculopalatal tremor (OPT) is a delayed complication of damage to the dentato-rubro-olivary pathway (Guillain-Mollaret triangle) and subsequent hypertrophic olivary degeneration. Mixed torsional-vertical pendular nystagmus in OPT has been considered to signify unilateral brainstem damage while symmetrical vertical nystagmus has been regarded to indicate bilateral disease. However, 3-dimensional oculographic analysis of OPT has been sparse. METHODS: In 8 patients with OPT; binocular 3-dimensional analyses of ocular oscillations were performed by using a magnetic search coil technique. Lateralization of the lesions was determined by the imaged olivary hypertrophy in the MRI. RESULTS: One patient had conjugate vertical pendular nystagmus and four showed mixed torsional-vertical pendular nystagmus. Two patients showed mixed horizontal-torsional-vertical nystagmus. One patient had predominantly horizontal pendular nystagmus. MRI demonstrated increased signal or hypertrophy of the inferior olivary nucleus, unilateral in six and bilateral in two. Unilateral olivary changes were associated with mixed torsional-vertical nystagmus in three patients, mixed horizontal-torsional-vertical nystagmus in another two patients, and predominantly horizontal pendular nystagmus in the remaining one patient. Bilateral olivary changes were visible in one patient with conjugate vertical pendular nystagmus and in the other patient with mixed torsional-vertical nystagmus. Palatal tremor appeared to be symmetrical in all patients. CONCLUSIONS: Three-dimensional analyses of OPT indicate that conjugate vertical and mixed torsional-vertical pendular nystagmus do not correspond to the laterality of signal changes in the inferior olivary nucleus. Ocular oscillations often have all the vertical, horizontal and torsional components.
Brain Stem ; Humans ; Hypertrophy ; Magnetic Resonance Imaging ; Nystagmus, Pathologic ; Olivary Nucleus ; Telescopes ; Tremor*

PURPOSE: Palatal myoclonus(PM) is an involuntary cyclic movement of the soft palate and is known to be caused by the hypertrophic degeneration of the inferior oilvary nucleus of the medulla, secondary to the dentato-rubro-tegmental tract lesions. Our purpose is to describe the brain magnetic resonance(MR) imaging findings in palatal myoclonus. MATERIALS AND METHODS: We retrospectively analyzed the locations and causes of primary lesions in the dentato-rubro-tegmental tract and correlated them with changes in MR signal intensity and size of the inferior olive on T2-weighted MR images in 10 patients with palatal myoclonus. RESULTS: All cases showed hyperintensity in one or both inferior olive and six cases showed accompaning enlargement. The locations of the primary lesions were dorsal aspect of pons(central tegmental tract) in eight patients and the dentate nucleus in one, and no lesion was found in the dentato-rubro-tegmental tract in one. Among eight patients who had lesions in the ports, the ipsilateral inferior olivary nuclei showed changes in five and bilateral olive were involved in three. In the case with a lesion in the dentate nucleus, the contralateral inferior olivary nucleus was involved. The causes of primary lesions were hemorrhage in eight cases and traumatic brain stem injury in one. CONCLUSION: MR specifically showed enlargement and hyperintensity of the inferior olivary nucleus on T2-weighted images and matching lesions in the ports or the dentate nucleus in patients with palatal myoclonus.
Brain ; Brain Stem ; Cerebellar Nuclei ; Hemorrhage ; Humans ; Myoclonus ; Olea ; Olivary Nucleus ; Palate, Soft ; Retrospective Studies

The development of involuntary movement by the lesion in the brainstem and spinal cord has been rarely reported. We report a 56-year-old man who suffered from bilateral dystonic tremor and left hemiparesis by an acute cervicomedullary infarction. The patient had acute infarcted lesion on the anterior-medial cervicomedullary junction located at the inferior olivary nucleus. Current study suggests that the involvement of inferior olivary nucleus in lower medulla could be a cause to develop dystonic tremor by cervicomedullary lesions.
Brain Stem ; Dyskinesias ; Dystonia ; Humans ; Infarction* ; Middle Aged ; Olivary Nucleus ; Paresis* ; Spinal Cord ; Tremor*

Palatal myoclonus is a rare disorder described as separable from the general group of myoclonias as a clinical and antomical entity result from lesion involving the dentato-rubro-olivary pathway and the inferior olivary nucleus. This 21-year-old man was injured in a fall from the roof. On admission to the hospital, he had cerebral contusion and occipital bone fracture with other multiple trauma. On the eleventh day after the injury, he began showing rhythmic, 150/min, bilateral contraction of the palate. This movement disorder has hitherto been considered untreatable when idiopathic origin. But several reports describe improvement of palatal myoclonus during sleep or medical treatment. In this case, palatal myoclonus was absent during sleep and it responded well to oral administration of clonazepam. We report a case of palatal myoclonus which developed after trauma for the first time in Korea.
Administration, Oral ; Clonazepam ; Contusions ; Humans ; Korea ; Movement Disorders ; Multiple Trauma ; Myoclonus* ; Occipital Bone ; Olivary Nucleus ; Palate ; Young Adult