Quantitative video-fluoroscopic analysis of swallowing in infants

The Impact of Videofluoroscopic Pulse Rate on Duration and Kinematic Measures in Infants and Adults with Feeding and Swallowing Disorders

This investigation assessed the impact of temporal resolution during a videofluoroscopic evaluation of swallowing (VFSS) on measures of duration and kinematics. Thirty adult and ten infant swallow studies, all acquired at 30 frames and 30 pulses per second, were obtained from a New Mexico hospital. All swallow studies were altered to simulate 15 and 5 pulses per second. Duration measures included pharyngeal response time, duration of upper esophageal sphincter (UES) opening, velopharyngeal closure duration and total swallow duration. Kinematic measures were assessed in adults only and included peak hyoid position and extent of UES opening during the swallow. Analysis of outcome measures was performed and compared across the three temporal resolutions (30, 15, and 5 pulses per second). For data points where normative values are available, we evaluated the impact of temporal resolution on clinical determination (i.e., did a change in pulse rate alter the clinical classification). Kinematic and duration measures were altered with changes in pulse rate and these changes increased as temporal resolution decreased. For outcome measures where normative values are available, accuracy of clinical determination decreased with decreased pulse rate. Temporal resolution impacts duration and kinematic measures. However, the direction of these changes is unpredictable, indicating sensitivity and specificity are both affected. Without a predictable impact, the use of lower pulse rates may alter clinical impressions and treatment recommendations yielding inappropriate treatment goals and treatment duration.

Prediction of Pharyngeal 3D Volume Using 2D Lateral Area Measurements During Swallowing

This study evaluated the validity of pharyngeal 2D area measurements acquired from the lateral view for predicting the actual 3D volume in healthy adults during swallowing. Seventy-five healthy adults (39 females, 36 males; mean age 51.3 years) were examined using 320-row area detector computed tomography (320-ADCT). All participants swallowed a 10 mL honey-thick barium bolus upon command while seated in a 45° semi-reclining position. Multi-planar reconstruction images and dynamic 3D-CT images were obtained using Aquilion ONE software. Pharyngeal 2D area and 3D volume measurements were taken before swallowing and at the frame depicting maximum pharyngeal constriction. Pharyngeal volume before swallowing (PVhold) was accurately predicted by 2D area (R2 = 0.816). Adding height and sex to the model increased R2 to 0.836. Regarding pharyngeal volume during maximum constriction (PVmax), 2D area also exhibited acceptable predictive power (R2 = 0.777). However, analysis of statistical residuals and outliers revealed a greater tendency for prediction errors when there is less complete constriction of the pharynx as well as asymmetry in bolus flow or movement. Findings highlight the importance of routinely incorporating anterior-posterior views during VFSS exams. Future work is needed to determine clinical utility of pharyngeal volume measurements derived from 320-ADCT.

Findings of a videofluoroscopic swallowing study in patients with dysphagia

Objective

Swallowing examination is crucial in patients with dysphagia. We aimed to compare qualitative and quantitative videofluoroscopic swallowing study (VFSS) results to provide reference for standardizing quantitative parameters.

Materials and methods

In total, 117 patients with dysphagia were included, 38 with Parkinson's disease and 39 and 40 in convalescence following cerebral hemorrhage and infarction. VFSS was both qualitatively and quantitatively analyzed.

Results

A significant difference of Oral transit time was found between the oral motor function grades (p < 0.001), also was swallowing reaction times found between swallowing reaction duration grades (p < 0.001), and soft palate lift duration between the soft palate lift grades (p < 0.001). Superior hyoid bone movement (p < 0.001), anterior hyoid bone movement (p < 0.001), hyoid pause time (p < 0.001), and hyoid movement duration (p = 0.032) had significant differences between the hyoid laryngeal complex movement grades, as did the pharyngeal cavity transit time among the cricopharyngeal muscle opening duration grades (p < 0.001). The laryngeal vestibule closure duration differed among the glottic closure grades (p < 0.001). No statistically significant difference in upper esophageal sphincter opening diameter (p = 0.682) or duration (p = 0.682) among the cyclopharyngeal muscle opening duration grades. The pharyngeal area at rest did not significantly differ among the different vallecular residue (p = 0.202) and pyriform sinus residue (p = 0.116) grades.

Conclusion

Several quantitative parameters can reflect the swallowing assessment process well. Further optimization of quantitative parameters is recommended.

Sucking and drinking behaviour in preweaned dairy calves in the first five weeks of life

Background

Nursing and sucking are essential for adequate nourishment of preweaned calves and the relationship between sucking indices has not been studied. The goal of this study was to investigate the number of sucks per litre of milk and per minute of drinking and the amount of milk ingested per suck in healthy preweaned calves. Correlation coefficients were calculated for the relationships between these variables. Eighteen healthy calves were used from birth to 5 weeks of age, and five measurements were made at the end of weeks 1 to 5. The calves were randomly divided into three groups and offered milk twice daily in a bucket with a rubber nipple. The amount of milk offered per day was equal to 12% of body weight in group A and 16% of body weight in group B. Calves in group C were offered as much milk as they wanted during each feeding period. The duration of drinking was determined with a stopwatch, and the number of sucks was counted with a handheld tally counter. The variables drinking duration, total amount consumed and the number of sucks required were used to calculate the number of sucks/min, the number of sucks/L, the amount ingested per suck and drinking speed.

Results

The number of sucks/min ranged from 113 to 133 and increased significantly during the study period. The mean number of sucks/L decreased from 204 in week 1 to 141 in week 5 and drinking speed increased from 0.6 to 1.0 L/min. There were significant correlations between the number of sucks/L of milk and the amount of milk ingested per suck, drinking duration, total amount consumed and drinking speed. Drinking speed was positively correlated with the amount of milk ingested per suck and the total amount of milk consumed, and negatively correlated with drinking duration.

Conclusions

These findings show that drinking variables of calves offered different amounts of milk vary little and significant changes occur during the same period with respect to the number of sucks/L of milk and the amount of milk ingested per suck. Several drinking variables are significantly correlated with other variables.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12917-022-03280-x.

Developing a Protocol for Quantitative Analysis of Liquid Swallowing in Children

PURPOSE

Objective measures in videofluoroscopic swallow studies (VFSSs) can quantify swallow biomechanics. There are a wide array of validated measures studied in infants, children, and adults. There is a need for a pediatric VFSS protocol that consists of a small number of vital, time efficient, and clinically relevant measures. In this study, we aimed to establish a standard protocol for quantitative VFSS analysis in children.

METHOD

Protocol development began with a systematic literature review, which identified 22 quantitative and eight descriptive measures available in the literature. A pediatric VFSS database of 553 children was collected using a standardized VFSS protocol. Studies were evaluated using the 30 previously reported measures covering displacement and timing parameters as well as penetration-aspiration and residue. Measures were tested for rater reliability and internal consistency. Measures meeting acceptable values for protocol inclusion were included in the final protocol (Cronbach's alpha > .53).

RESULTS

Interrater and intrarater reliability of 17 measures met acceptable reliability levels. During internal consistency testing, we removed six further measures based on Cronbach's alpha levels indicating that two or more measures were equivalent in measuring the same aspect of swallow biomechanics in children. A VFSS protocol of reliable, valid, and obtainable objective quantitative (n = 6) and descriptive measures (n = 3) with separate protocols for young infants (≤ 9 months) and older children was established.

CONCLUSIONS

A standardized quantitative VFSS protocol for children has been developed to suit two age groups (≤ 9 and > 9 months old). Consistent VFSS administration and reporting support assessment over time and across disease groups. Future research should focus on how this information can be used by clinicians to produce individualized treatment plans for children with swallowing impairment.

Variability in Swallowing Biomechanics in Infants with Feeding Difficulties: A Videofluoroscopic Analysis

Clinicians performing feeding evaluations in infants often report swallow variability or inconsistency as concerning. However, little is known about whether this represents pathological incoordination or normal physiologic variance in a developing child. Our retrospective study explored quantitative videofluoroscopic measures in 50 bottle-fed infants (0-9 months) referred with feeding concerns. Our research questions were as follows: Is it possible to assess swallow to swallow variability in an infant with feeding concerns, is there variability in pharyngeal timing and displacement in infants referred for videofluoroscopy, and is variability associated with aspiration risk? Measures were taken from a mid-feed, 20-s loop recorded at 30 frames per second. Each swallow within the 20-s loop (n = 349 swallows) was analysed using quantitative digital measures of timing, displacement and coordination (Swallowtail™). Two blinded raters measured all swallows with strong inter-rater reliability (ICC .78). Swallow frequency, suck-swallow ratio, residue and aspiration were also rated. Variability in timing and displacement was identified across all infants but did not correlate with aspiration (p > .05). Sixteen infants (32%) aspirated. Across the cohort, swallow frequency varied from 1 to 15 within the 20-s loops; suck-swallow ratios varied from 1:1 to 6:1. Within-infant variability in suck-swallow ratios was associated with higher penetration-aspiration scores (p < .001). In conclusion, pharyngeal timing and displacement variability is present in infants referred with feeding difficulties but does not correlate with aspiration. Suck-swallow ratio variability, however, is an important risk factor for aspiration that can be observed at bedside without radiation. These objective measures provide insight into infant swallowing biomechanics and deserve further exploration for their clinical applicability.

Thickened liquids: do they still have a place in the paediatric dysphagia toolkit?

PURPOSE OF REVIEW

Use of thickened fluids has long been a cornerstone of dysphagia management. However, clinicians and researchers are increasingly questioning their effectiveness and highlighting potential harms. This review aims to present the current state of the evidence for use of thickened fluids in children.

RECENT FINDINGS

The relationship between aspiration and respiratory infection is complex. The role of thickened fluids in improving respiratory health is limited and contradictory. A high level of variability exists in all aspects of thickened fluid use. Little is known about patient and family perspectives on meaningful endpoints for intervention.

SUMMARY

Clinicians should be open and transparent in their decision making with patients and families, acknowledging the limited evidence and the need for individualised care. Further research is needed to establish the efficacy of thickened fluid use in children with regard to improvements in respiratory health, fluid intake and child and family wellbeing.

Quantifying Bolus Residue and Its Risks in Children: A Videofluoroscopic Study

Purpose Postswallow residue is a clinical sign of swallow impairment and has shown a strong association with aspiration. Videofluoroscopy (videofluoroscopic study of swallowing [VFSS]) is commonly used to visualize oropharyngeal swallowing and to identify pharyngeal residue. However, subjective binary observation (present or absent) fails to provide important information on volume or location and lacks objectivity and reproducibility. Reliable judgment of changes in residue over time and with treatment is therefore challenging. We aimed to (a) determine the reliability of quantifying pharyngeal residue in children using the bolus clearance ratio (BCR), (b) determine associations between BCR and other timing and displacement measures of oropharyngeal swallowing, and (c) explore the association between BCR and penetration-aspiration in children. Method In this single-center retrospective observational study, we obtained a set of quantitative and descriptive VFSS measures from 553 children (0-21 years old) using a standard protocol. VFSS data were recorded at 30 frames per second for quantitative analysis using specialized software. Results Good interrater (ICC = .86, 95% CI [.74, .961], p < .001) and excellent intrarater reliability was achieved for BCR (ICC = .97, 95% CI [.91, 1.000], p = 001). Significant correlations between BCR and pharyngeal constriction ratio and total pharyngeal transit time were reported (p < .05). Using binomial logistic regression modeling, we found BCR was predictive of penetration-aspiration in children, χ²(13) = 58.093, p < .001, 64.9%. Children with BCR of ≥ 0.1 were 4 times more likely to aspirate. Conclusion BCR is a reliable, clinically useful measure to quantify postswallow residue in children, which can be used to identify and treat children with swallow impairments, as well as to measure outcomes of intervention.

Predicting penetration-aspiration through quantitative swallow measures of children: a videofluoroscopic study

PURPOSE

Quantitative measures have improved the reliability and accuracy in interpretation and reporting of videofluoroscopy (VFSS). Associations between quantitative VFSS measures and swallow safety in children are not widely reported. The ability to predict aspiration in children, even if not observed during brief VFSS, will improve diagnostic reporting and potentially reduce the need for extended radiation time. The aims of this study were to determine associations between quantitative fluoroscopic swallow measures and penetration-aspiration and to predict likelihood of penetration-aspiration.

METHODS

We selected videofluoroscopic data of 553 children from a pediatric hospital database for this single-center retrospective observational study. A standard protocol of VFSS administration was used and data were recorded at 30 frames-per-second. A set of quantitative and descriptive swallow measures was obtained using a specialized software with satisfactory inter-rater and intra-rater reliability. Binomial logistic regression with backward likelihood ratio was conducted, while controlling for age, gender, and etiology.

RESULTS

We found bolus clearance ratio (BCR), pharyngeal constriction ratio (PCR), duration to hyoid maximal elevation (Hdur), and total pharyngeal transit time (TPT) to be predictive of penetration-aspiration in children. PCR was the most predictive of penetration-aspiration in children (61.5%). Risk of aspiration was more than 100 times, when BCR =  ≥ 0.1, TPT =  ≥ 2 s, Hdur =  > 1 s or PCR =  ≥ 0.2 (p < 0.05 for all measures).

CONCLUSION

The results confirm the potential of objective quantitative swallow measures in predicting the risk of aspiration in children with dysphagia. These parameters provide predictive measures of aspiration risk that are clinically useful in identifying children of concern, even if no aspiration is observed during VFSS.