Table 1—

Summary of diagnostic tests of aspiration

EvaluationBenefitsLimitations
Chest radiographInexpensive and widely available, assesses accumulation of injury over timeInsensitive to early subtle changes of lung injury
HRCTSensitive in detecting lung injury, such as bronchiectasis, tree-in-bud opacities and bronchial thickeningLess radiation than conventional CTAssesses accumulation of injury over timeMore radiation exposure than plain radiographExpensive
VSSEvaluates all phases of swallowingEvaluates multiple consistenciesFeeding recommendations made at time of studyInformation limited if child consumes only small quantitiesDifficult to perform in child who has not been feeding by mouthRadiation exposure proportional to study durationCannot be performed at bedsideLimited evaluation of anatomyEvaluates one moment in timeExpensive
FEES / with sensory testingAbility to thoroughly evaluate functional anatomyEvaluates multiple consistenciesCan assess risk of aspiration in nonorally feeding child; airway protective reflexes can be assessedFeeding recommendations made at time of studyVisual feedback for caregiversCan be performed at bedsideNo radiation exposureBlind to oesophageal phase and actual swallowInvasive and may not represent physiological swallowing conditionsEvaluates one moment in timeNot widely availableExpensive
BALEvaluates anatomy of entire upper and lower airwaysSamples the end-organ of damageSample available for multiple cytological and microbiological testsBecoming more widely availableUncertainty regarding interpretation of lipid-laden macrophage indexIndex cumbersome to calculateRequires sedation or anaesthesiaInvasiveExpensive
Oesophageal pH monitoringCurrent gold standard for diagnosis of GOREstablished normative data in childrenBlind to majority of reflux eventsDifficult to establish causal relationship between GOR and aspirationSomewhat invasiveEvaluates one moment in time
Oesophageal impedance monitoringLikely future gold standard for diagnosis of GOR with supra-oesophageal manifestationsAble to detect acid and nonacid reflux eventsDetects proximal reflux eventsAble to evaluate for GOR without stopping medicationsLack of normative data for childrenSomewhat invasiveExpensive and cumbersome to interpretNot widely availableEvaluates one moment in time
Gastro-oesophageal scintigraphyPerformed under physiological conditionsLow radiation exposurePoor sensitivityMay not differentiate between aspiration from dysphagia or GOR
Radionuclide salivagramChild does not have to be challenged with food bolusLow radiation exposureUnknown sensitivityUnknown relationship to disease outcomesEvaluates one moment in time
Dye studiesCan be constructed as screening test or confirmatory testCan evaluate aspiration of secretions or feedsRepeating over time allows for broader evaluationUncertainty in interpretation owing to variability of techniqueCan only be performed in children with tracheostomies
  • HRCT: high-resolution computed tomography; VSS: videofluoroscopic swallow study; FEES: fibreoptic-endoscopic evaluation of swallowing; BAL: bronchoalveolar lavage; CT: computed tomography; GOR: gastro-oesophageal reflux.