Week 8.1 Flashcards
Describe the appearance of a T1 weighted brain MRI.
white matter is hyperintense
Describe the appearance of a T2 weighted brain MRI.
white matter is hypo intense and CSF is hyperintense
Describe the appearance of a FLAIR MRI.
white matter and CSF is hypointense
What is the density of water on CT?
0 Hounsfield units
What are the major risks of angiopathy?
- vascular injury
- ischemic stroke
- intracerebral hemorrhage
- iodinated contrast complications
- prolonged x-ray exposure
What is true of all enhancing lesions?
they have disrupted the BBB
Why are CT angiograms less risky than conventional catheter angiograms?
because they involve a venous rather than an arterial injection
What are the primary risks of CT?
- ionizing radiation exposure
- iodinated contrast exposure
What are the potential complications of iodinated contrast exposure?
- allergic reaction
- nephrotoxicity
What is a diffusion weighted MRI?
One in which areas of restricted fluid diffusion appear hyperintense
What are the primary risks of MRI?
- claustrophobia
- long scan time
- ferromagnetic metals can’t go through
- gadolinium-associated sclerosing dermopathy in those with renal failure
An fMRI measures what?
changes in oxygen delivery
What is SPECT imaging?
- single photon emission CT
- inject a radioactive compound into the blood
- follow it, much like an fMRI
How can you identify the medulla on MRI?
it is at the level of the cerebellum and is smaller (compared to the pons)
How can you identify the third ventricle on MRI?
it is connected to the lateral ventricles and is superior compared to the more inferior fourth ventricle
Name the four phases of swallowing.
- preparatory
- oral
- pharyngeal
- esophageal
The preparatory phase of swallowing involves which cranial nerves?
V, VII, XII
What does the oral phase of swallowing involve?
elevating the tongue to the palate and propelling the bolus into the pharynx while also closing the soft palate
The pharyngeal phase of swallowing is initiated by what?
the food bolus contacting the pharynx
What happens during the pharyngeal phase of swallowing?
- vocal folds close
- larynx elevates
- epiglottis shuts
- peristaltic contraction of pharyngeal constrictors
- relaxation of the cricopharyngeus muscle (UES)
Which brainstem nuclei mediate swallowing?
- hypoglossal
- solitary
- ambiguous
The pharyngeal phase of swallowing involves primarily which CN?
the vagus
What is the role of the reticular formation in swallowing?
coordinate activity of the involved brainstem nuclei
What is the purpose of the ambiguous nucleus in swallowing?
innervate branchial-derive muscles
What is the role of CN IX in swallowing?
visceral afferent to help control swallowing
The solitary nucleus plays what role in swallowing?
obtains sensory input to modulate swallowing
Describe the input of corticobulbar tracts on swallowing?
bilateral innervation of the RAS
What two things can cause delayed initiation of swallow reflex?
- weakness of tongue
- numbers of posterior palate and pharynx
What two things can cause nasal reflux during swallow?
- weakness of palatal elevators
- weakness of upper pharyngeal constrictors
Problems with which cranial nerve contribute most to nasal reflux during swallowing?
the vagus which innervates the palatal elevators and superior pharyngeal constrictors
What two problems can lead to aspiration during swallowing?
- weakness of pharyngeal and laryngeal muscles
- pharyngeal numbness
Name three complications of dysphagia.
- airway obstruction
- aspiration pneumonia
- poor nutrition
Four methods for identifying dysphagia?
- patient self-reporting
- CN exam
- bedside swallow test
- modified barium swallow
Signs and symptoms of dysphagia.
- difficulty swallowing
- weight loss
- failure to finish meals
- coughing while eating
Problems swallowing liquids suggest what compared to problems swallowing solids.
- liquids: neurologic
- solids: mechanical problem (e.g. esophageal stricture)
Bedside swallow test is abnormal if what occurs?
- coughing during or within 1 minute
- wet/hoarse quality to the person’s voice after
What are the five dietary textures?
- liquid
- thickened liquid
- puree
- mechanical soft
- regular
What texture of food is often best for stroke patients?
a middle texture like puree
Why can’t stroke patients handle liquids or solids?
- liquids pose an aspiration risk
- solids are unlikely to be cleared and therefore obstruct the airway
Name five swallowing maneuvers that can help those with dysphagia.
- sit fully upright
- chin tuck/chin up
- head turn
- small bites
- double swallow
The chin up feeding maneuver is best for who?
those with a weak tongue and struggling with the oral phase
The chin tuck feeding maneuver is best for who?
those with weak pharyngeal muscles because it narrows the pharyngeal space
What are the cons go NG tubes?
- uncomfortable and pulled out
- increased gastric reflux
- increased saliva
- interferes with airway protection
