We present a case of a 57-year-old woman who underwent gamma-knife radiosurgery (GKRS) for pontine metastasis. Magnetic resonance (MR) imaging 2.8 months after GKRS showed T₂ hyperintensity and hypertrophy of the left inferior olivary nucleus (ION) without gadolinium enhancement and smaller pontine metastasis. We diagnosed the signal change in the left ION as hypertrophic olivary degeneration (...

A clinicopathological case of pontine metastatic tumour is reported with an oculomotor syndrome including bilateral horizontal gaze paralysis affecting saccades and foveal pursuit. During full-field pursuit, oculocephalic movement, and after caloric stimulation, the right eye alone was able to move slowly only 30 degrees to the right of the midline. Convergence and vertical eye movements were u...

Microinjections of the cholinergic agonist carbachol into a caudal part of the pontine reticular formation of the rat induce a rapid eye movement sleep-like state. This carbachol-sensitive region of the pontine reticular formation is innervated by cholinergic neurons in the pedunculopontine and laterodorsol tegmental nuclei. The same population of cholinergic neurons also project heavily to the...

This study was performed to test the hypothesis that cholinoceptive basal forebrain systems can significantly influence cholinoceptive pontine mechanisms known to be important for generating rapid eye movement (REM) sleep. This hypothesis was examined by microinjecting the cholinergic agonist carbachol or saline (vehicle control) into the pons, the basal forebrain, or simultaneously into the po...

pontine reticular formation induces rapid-eye-movement (REM) sleep with atonia in intact animals, and lesions at this pontine site cause REM sleep without atonia.1,2,3 REM sleep without atonia is also induced by lesions in the medial medulla.4,5 In the decerebrate cat, both chemical and electrical stimulation delivered to the pontine inhibitory regions, as well as to portions of the medial medu...

We present a female patient with central positioning nystagmus and vertigo (c-PPV) due to a pontine stroke. To our knowledge this is the first report of central upbeat positioning nystagmus caused by pontine lacunar stroke. This report, together with those published previously, supports the existence of a crossing ventral tegmental tract in humans.

Pre- and postoperative pneumoencephalo-roulette tomography has been carried out in two cases of primary pontine haemorrhage with long survival. A pontine or cerebellar atrophy was revealed in case 1, in whom an intrapontine haematoma was removed. A markedly hollowed pons on the affected side has been demonstrated nearly five months after ventriculoatrial shunting in case 2.

Two patients with small primary pontine hemorrhage developed a syndrome identical to ataxic hemiparesis, one of the lacunar syndromes of Fisher. The possible mechanisms of the homolateral cerebellar signs, pyramidal signs, and dysarthria are discussed. Lesions of the ipsilateral pontine nuclei may be responsible for the homolateral ataxia.

The anterior corticospinal tract (CST) has been suggested as one of the ipsilateral motor pathways, which contribute to motor recovery following stroke. In this study, we report on a patient who showed deterioration of pre-existing hemiparesis due to an injury of the ipsilateral anterior CST following a pontine infarct, as evaluated by diffusion tensor tractography (DTT). A 55-year-old male pat...

The micturition reflex is one of the autonomic reflexes, but the release of urine is regulated by voluntary neural mechanisms that involve centers in the brain and spinal cord. The micturition reflex is a bladder-to-bladder contraction reflex for which the reflex center is located in the rostral pontine tegmentum (pontine micturition center: PMC). There are two afferent pathways from the bladde...