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Objectives/Hypothesis Nasal obstruction is the principal symptom that drives patients with rhinosinus disease to seek medical treatment. However, patient perception of obstruction often bears little relationship to actual measured physical obstruction of airflow. This lack of an objective clinical tool hinders effective diagnosis and treatment. Previous work has suggested that the perception of nasal patency may involve nasal trigeminal activation by cool inspiratory airflow; we attempt to derive clinically relevant variables following this phenomenon. Study Design Prospective healthy cohort. Methods Twenty-two healthy subjects rated unilateral nasal patency in controlled room air using a visual analog scale, followed by rhinomanometry, acoustic rhinometry, and butanol lateralization thresholds (BLTs). Each subject then immediately underwent a computed tomography scan, enabling the construction of a real-time computational fluid dynamics (CFD) nasal airway model, which was used to simulate nasal mucosa heat loss during steady resting breathing. Results Among all measured and computed variables, only CFD-simulated peak heat loss posterior to the nasal vestibule significantly correlated with patency ratings ( r = −0.46, P < .01). Linear discriminant analysis predicted patency categories with 89% success rate, with BLT and rhinomanometric nasal resistance being two additional significant variables. As validation, CFD simulated nasal resistance significantly correlated with rhinomanometrically measured resistance ( r = 0.41, P < .01). Conclusions These results reveal that our noses are sensing patency via a mechanism involving localized peak nasal mucosal cooling. The analysis provides a strong rationale for combining the individualized CFD with other objective and neurologic measures to create a novel clinical tool to diagnose nasal obstruction and to predict and evaluate treatment outcomes. Level of Evidence 4 Laryngoscope, 124:589-595, 2014 [ABSTRACT FROM AUTHOR]

Although smell loss has several potential etiologies (e.g., head trauma, allergic rhinitis, and enlarged adenoids) that are common among children, studies evaluating the prevalence of olfactory dysfunction in the pediatric population are rare. Several challenges confront the clinician or researcher hoping to evaluate odor identification ability in young children. Children are likely to be unfamiliar with many of the odor stimuli used in adult tests and have limited ability to read and identify labels to select from alternative choices, which is the typical adult response option. Consequently, specialized forms of olfactory tests must be developed for this population. Based on the format of the San Diego Odor Identification Test 1 and the delivery system of the Brief Smell Identification Test, 2 we are developing a short form odor identification test utilizing standardized odor stimuli in which participants match 6 odorants to pictures of the odor source. The pilot version of this test is being administered to children between the ages of 3–17 as part of the pre-surgical intake evaluation at the A.I. duPont Hospital for Children and as part of basic research studies at the Monell Center. The hospital study population is broad and includes children undergoing ear, nose, and throat surgery as well as controls subjects (children undergoing general surgery), with approximately 50 children per week eligible for evaluation. To improve correct interpretation of the results, stimulus familiarity is evaluated by having the child's parent/guardian also complete the test and answer a short questionnaire about the child's experience with the various odor stimuli. The challenges confronted in studying this clinical population as well as extrapolation to larger populations will be discussed. [ABSTRACT FROM AUTHOR]

The impact of chronic rhinosinusitis (CRS) on the olfactory mucosa (OM) is dramatic. Cellular profiles and epithelial integrity in OM biopsies were evaluated using histological and immunohistochemical methods to define a strategy for future histological studies of CRS. We have examined nasal biopsies of 54 CRS patients (18–63 years old) and have defined specific histopathological patterns of the OM: normal pseudostratified, goblet cell hyperplasia, squamous metaplasia, and erosion. Goblet cell hyperplasia was most similar to a normal pseudostratified OM pattern but with goblet cells intermixed in the apical layers. Squamous metaplasia exhibited an absence of olfactory supporting cells and had olfactory sensory neurons that were morphologically abnormal. It is unknown if these neurons would be functional in this type of tissue transformation. The pattern of erosion exhibited a severe loss of epithelial layers and a higher prevalence of infiltrating inflammatory cells within the olfactory epithelium when compared to the other OM patterns. Although it is not known if the OM patterns we have noted correspond to specific stages or distinct pathways of the disease, the template proposed here can be used in further studies to understand how the histopathological progression of CRS relates to olfactory loss and the response to treatment. [ABSTRACT FROM AUTHOR]

Acceptance of and expressed preference for varying levels of salt (NaCl) were assessed among children 3-6 years of age. 20 children received 0, 0.17, and 0.34 M NaCl in aqueous solution, and 20 received these same NaCl concentrations in a soup broth. In both groups, children were asked to ingest as much as they wanted to each stimulus during brief, sequential presentations and to indicate which stimulus they preferred in a series of paired-comparison presentations. A striking, context-specific reaction to the taste of salt was observed on both measures. Children in this age group strongly rejected even the moderate level of salt in water relative to unsalted water. In contrast, the most highly salted soup was well accepted and preferred to either unsalted or moderately salted soup by the majority of children. [ABSTRACT FROM AUTHOR]

Two studies investigated the human infant's response to salt during development. In the first study, measures of intake and sucking were obtained from two groups of infants, newborns, and 4- and 8-month-olds, in response to brief presentations of two concentrations of salt (0.2 or 0.4 M) and water. For several measures of sucking and for intake, there were significant age and concentration effects. Generally, newborn infants tended to reject saline relative to water more than did 4- to 8-month-old infants. This result, consistent with previously published research, suggests a developmental change in salt acceptability and, probably, sensitivity in the human infant. In the second longitudinal study, the response to salted (0.15 M) versus unsalted formulas was evaluated monthly in infants 2 to 7 months of age. Again, a developmental change was observed. Based on some sucking measures, younger infants appeared to be indifferent to the salted formula relative to the unsalted formula whereas older infants tended to reject the salted formula, presumably because either it was less sweet than the unsalted formulas or because it was novel. These data are consistent with the hypothesis developed from animal model studies that during early human postnatal development, transductive elements sensitive to saltiness mature. [ABSTRACT FROM AUTHOR]

Human newborns (birth-6 days) and older infants (14-180 days) were allowed to ingest both urea (0.12-0.24 M) in a mildly sweet diluent and the diluent alone, and multiple measures of responsivity were obtained (relative intake, sucking behavior, and hedonic ratings based on facial expressions and body movements). For newborns, there was no indication of rejection of urea relative to the diluent in measures of intake or sucking behavior; rather, their responses were predominantly controlled by the order of presentation of the two tastes. In contrast, older infants tended to reject all concentrations of urea according to these measures. Hedonic ratings provided an indication of limited rejection of the bitter taste by newborns, but older infants were still found to respond more consistently. These data suggest there is an early developmental change in bitter taste perception. [ABSTRACT FROM AUTHOR]

Human infants less than 4 months of age ingested water and moderate concentrations of sodium chloride solution (0.10-0.20 M) in equal amounts. In contrast, infants 4-24 months of age exhibited heightened acceptance of saline solution relative to water. Such a developmental change in salt acceptability is consistent with a hypothesis of postnatal maturation of peripheral and/or central structures underlying this response. Children 31-60 months of age tended to reject saline solution relative to water. This change may in part reflect the effects of experience. [ABSTRACT FROM AUTHOR]

A response from the authors of the article "Regional Peak Mucosal Cooling Predicts the Perception of Nasal Patency" in a 2013 issue is presented.