The medullary palsy is called bulbar palsy, also known as true bulbar palsy. When a motor nerve nucleus within the medulla oblongata, or a cranial nerve from the medulla oblongata (including the glossopharyngeal, vagus and hypoglossal nerves), causes paralysis, a group of symptom clusters appear, mainly manifesting choking on drinking and eating, difficulty swallowing, hoarseness or loss of voice, etc. Where the lesion directly damages the medulla oblongata or related cranial nerves, it is called true medulla oblongata palsy. If the lesion is in the pontocerebrum or above the pontocerebrum, causing the motor nucleus to lose its innervation in the upper part of the medulla oblongata, the medullary palsy is called pseudo-medullary palsy. What are the causes of pseudomyelinating palsy? Vascular Parkinson’s syndrome: Vascular Parkinsonism (VP) is a disease caused by cerebrovascular factors, such as multiple lacunar infarction, basal nucleus accumbens, amyloid angiopathy, and subcortical white matter encephalopathy. The clinical features of the disease are similar to Parkinson’s disease (PD). In 1929 Critchley first proposed the concept of VP, the main clinical signs are tonicity, facial dullness, small broken gait, additional signs are: pseudobulbar palsy, cone bundle sign, cerebellar signs, dementia and urinary incontinence; in 1981 Critichley renamed it atherosclerotic pseudo-parkinsonian syndrome (arteriosclerotic pseudo- parkinsonism); other synonyms: lower body parkinsonism. The prevalence is unknown, accounting for about 3-12% of Parkinson’s syndromes. Vagus nerve injury: The vagus nerve is the longest traveled and most widely distributed cerebral nerve, which exits the skull together with the glossopharyngeal nerve and the paramedian nerve through the jugular foramen and travels down in the neck between the carotid artery and the internal jugular vein within the carotid sheath. The vagus nerve is a mixed nerve, with the nucleus suspensus, the nucleus solitarius and the nucleus of the trigeminal spinal tract coexisting with the glossopharyngeal nerve, so damage to the vagus nerve alone is rare and often occurs simultaneously with the glossopharyngeal nerve. Central pontine myelinolysis (CPM) is a lethal disease characterized by symmetric demyelination at the base of the pontine brain. First reported by Adams et al. (1959), the first case by Adams et al. in 1950, was observed in a young chronic alcoholic who was hospitalized with alcohol withdrawal symptoms, developed quadriplegia with pseudomyelinating palsy within a few days, and died soon after. The main finding on pathological examination was a large symmetrical demyelinating lesion at the base of the pontine brain, hence the name.