HC 4 Radiography + DSS Flashcards
How do we assess the pharynx by radiography?
= (modified) barium swallow or Dynamic Swallowing Study (DSS)
- accomplished by videofluoroscopy of video radiography:
- recording of the fluoroscopic image
- spatial resolution is not so much, but is generally adequate for most studies
- less radiation exposure
- easier manipulation of the images
What is a esophagram?
= radiographic examination of the esophagus
= barium meal or swallow
- often combined with examination of the stomach and duodenum
Which other equipment is used in radiography? Explain
•Rapid sequence digital radiography
−6 frames per second
−Excellent spatial resolution & easy manipulation of the images
−Relatively low radiation exposure
−Disadvantage: too few frames for some studies
•Cine-MRI and turbo- FLASH MRI:
−less or no radiation
−Not commonplace
•Videofluoromanometry:
−Dynamic and functional structural information
−Provides insights to bolus flow and pressures
What are our concerns regarding radiation exposure and safety?
- ALARA principle: As Low As Reasonably Achievable (there is no safe dose of radiation)
- balance between an effective study and minimizing long-term radiation risk: in the elderly the risk to health in missing aspiration or swallow impairment is far greater than the cumulative risk from low-dose radiation
When is it indicated to perform radiography?
- suspicion for silent aspiration
- Persistent dysphagia
- Odynophagia
- Aspiration
- Pulmonary pathology
- Chronic cough
- Regurgitation
- Weight loss
- Reflux or esophageal pathology
- After surgery or radiotherapy to the head and neck
- Full assessment of pharyngeal and esophageal phases
- Tailored
- Testing maneuvers or strategies
Why is DSS the optimal radiographic procedure?
−Provides information regarding transit and pathway bolus through oropharynx, hypopharynx, pharyngoesophageal segment and esophagus
−Ability to demonstrate motion
−Is general available
−From oral cavity, base of the tongue, valleculae, epiglottis, piriform sinuses, to pharyngoesophageal segment and cervical esophagus
What’s the difference between a lateral and a anterior posterior view?
- lateral view: better view on epiglottis and cricopharyngeus muscle
- anterior posterior view: better view
- on valleculae and piriform sinuses
- on asymmetries (unilateral weakness)
- on some pathologies e.g. Zenker’s diverticulum
What are possible observations during radiography?
−Penetration
−Aspiration
−Hyolaryngeal elevation
−Esophagus: abnormalities in anatomy and motility problems
−Epiglottic folding back
−Residue: valleculae and piriform sinus
−Stream (Posterior cricoid findings)
−During esophageal screen (large bolus of barium, barium tablet): transit time, completeness of bolus transfer, reflux, stasis, constrictions of the stream, presence of hiatal hernia
When is it indicated to perform DSS?
When complaints, signs/symptoms and/or histories
suggest
oral, pharyngeal, laryngeal or pharyngoesophageal dysfunction
to identify risks to
respiratory/pulmonary and nutrition/hydration health
and to target potential
behavioral, surgical or medical interventions more precisely and effectively
What are DSS’ limitations?
−Limited length of observation and repetition
−Technical limitations (e.g. two-dimensionality)
−Radiation exposure
−Dependence on the quality of images obtained
−Good positioning of the patient may be difficult
−Lack of attention to or experience with Fluoroscopic swallow study
−No information on pressures
−No information on sensation of tissues
−Inability of some patients to undergo the study
−Conditions can have an effect of swallow performance (e.g. not similar to real-life eating)
What are DSS’ contra-indications?
- when moving the patient is dangerous
- when rapid fluctuations
- when positioning is not possible
What does DSS attempt to do?
−Determine risks to respiratory system during eating/drinking
−Clarify and characterize variables that lead to such risks
−Modify variables (if possible)
−Elaborate patient’s potential for oral eating
Which variables could influence the patient performance and study success with DSS?
−Position
−Postural stability and flexibility
−Respiratory sufficiency
−Stamina and endurance
−Lubrication
−Bolus characteristics
−Competing behaviors and states
−Environment
−Adaptability
−Views
Why does the position of head/neck influence the swallow performance?
- alters the effect of gravity
- changes the relationships of structures and shapes of the chambers
- e.g. rotation -> increase/decrease size of piriform sinus
- e.g. neck flexion (buiging) -> changes shape of valleculae
- e.g. neck extension -> alters relationship between hyoid movement direction and the PES
Why does the postural stability and flexibility affect the swallow performance?
- Fine movements depend on a stable support structure (eg. airway)
- flexibility in posture is needed to apply compensatory strategies