Pontomedullary (caudal brainstem) disease Flashcards
What is the role of the pontomedullary area
This area is an essential part of the central nervous system from a functional point of view
- It provides motor and sensory innervation to the head and neck via cranial nerves VI-XII
- it connects the higher centers of the forebrain to the rest of the body via pathways that transmit motor (corticospinal or pyramidal tract) and sensory information (e.g., nociception, proprioception, touch, vibrations, temperature and itch sensations)
What are the roles of the “pons” area
The pons contains nuclei that relay signals from the forebrain to the cerebellum via the cerebellar peduncles
It contains areas responsible for:
- the regulation of sleep
- switching from inspiratory to expiratory respiration
- posture
- CN pathways and the nuclei of the trigeminal, abducenc, facial, vestibular and cochlear nerves
What are the roles of the medulla oblongata
The medulla oblongata primarily deals with autonomic functions to do with the cardiac, respiratory, vomiting and vasomotor centers
This is the area where the neurological fibres joining the brain to the spinal cord decussate
- the dorsal aspect of the medulla forms the ventral floor of the fourth ventricule
What are the clinical signs associated with a pontomedullary disease
Multiple cranial nerve deficits producing one or more of the following signs:
- jaw paralysis
- masticatory muscle atrophy
- decreased facial sensation
- decreased palpebral reflex
- lip paralysis, ear droop
- strabismus
- vestibular disturbances
- pharyngeal/laryngeal and tongue paralysis
Ipsilateral hemiparesis/plegia or tetraparesis/plegia
Ataxia if ambulatory
Depressed postural reactions
Intact reflexes
Increased muscle tone in affected limbs
May see irregular respiration
May see mental depression (due to disruption of ascending reticular activating system)
What would be your main differentials for pontomedullary disease
Infectious:
- FIP
- cryptococcosis
- toxoplasmosis
- bacterial infections
Neoplasia
- primary
- metastatic
Vascular
- ischemia
- hemorrhage
Trauma
Congenital
- storage disorders
- chiari malformations
