Radiation Dose During Videofluoroscopic Swallowing Studies and Associated Factors in Pediatric Patients

Fluoroscopic-Assisted Tongue Suspension: Advancement and Innovation in the Management of Complex Pediatric Obstructive Sleep Apnea

OBJECTIVES

The primary aim of this study is to describe a novel surgical technique developed for tongue base suspension (TBS). The second aim of this study is to assess the efficacy of the developed procedure by quantifying preoperative and postoperative polysomnographic outcomes for pediatric patients undergoing fluoroscopic-assisted tongue suspension (FATS) with the Encore System. Our hypothesis is that our FATS technique will provide at least a 50% reduction in the Apnea/Hypopnea Index (AHI), including in the medically complex pediatric population.

STUDY DESIGN

Retrospective case series.

METHODS

An electronic medical record review was conducted of patients who underwent FATS by a single surgeon at a tertiary care medical center between December 2019 and June 2022. Inclusion criteria included all patients <18 years old with evidence of OSA or sleep-disordered breathing and who had glossoptosis on sleep endoscopy. Data extracted from the medical record included age, gender, medical comorbidity history, reason for referral, history of airway surgeries, length of hospital stay, surgical complications data, and preoperative and postoperative polysomnographic data. Surgical success was defined by at least a 50% reduction in AHI.

RESULTS

Thirty patients (53.3% male) with a mean age of 6.3 (±5.3, 0.16-17) years underwent FATS over the study period. Most patients (93%) had an underlying comorbidity: cerebral palsy (37%), chromosomal abnormalities (23%), Down syndrome (13%), Pierre-Robin sequence (10%), and obesity (10%). The majority of patients (77%) were explicitly referred for tracheostomy placement secondary to failed management of OSA. 21 patients completed both preoperative and postoperative polysomnograms. The mean preoperative AHI, obstructive AHI (oAHI), and respiratory disturbance index (RDI) were 28.8 (±19.8), 30.8 (±19.6), and 30.5 (±19.3), respectively. The mean postoperative AHI, oAHI, and RDI were 7.3 (±9.2), 7.5 (±9.1), and 7.9 (±9.3), respectively. The mean change in AHI was -21.5 (±21.4) events/h (p < 0.01, 95% CI -29.0 to -11.4 events/h). The mean percentage decrease in AHI was 74.7%. The mean change in oAHI and RDI were -23.3 (±21.9) events/h (p < 0.01 95% CI- 39.9 to -21.4 events/h) and -22.5 (±21.5) events/h (p < 0.01, 95% CI- 31.5 to -12.4 events/h), respectively. The mean percentage decrease in oAHI and RDI was 75.6% and 73.8%, respectively. Surgical success occurred in 16 of the 21 (76%) patients. Of the 23 patients referred explicitly for tracheostomy placement, 21 (91%) were able to avoid tracheostomy placement secondary to improvements in OSA.

CONCLUSIONS

Patients undergoing fluoroscopic-assisted TBS revealed statistically significant improvements in AHI, oAHI, and RDI, with an overall surgical success rate of 76%. Complication rates were minimal, despite the complex nature of the study population. FATS should be considered a viable surgical approach in pediatric patients with an identified base of tongue obstruction and OSA.

LEVEL OF EVIDENCE

4 Laryngoscope, 134:S1-S9, 2024.

A Tutorial on Diagnostic Benefit and Radiation Risk in Videofluoroscopic Swallowing Studies

The videofluoroscopic swallowing study (VFSS) is a key tool in assessing swallowing function. As with any diagnostic procedure, the probable benefits of the study must be weighed against possible risks. The probable benefit of VFSS is an accurate assessment of swallowing function, enabling patient management decisions potentially leading to improved patient health status and quality of life. A possible (though highly unlikely) risk in VFSS is carcinogenesis, arising from the use of ionizing radiation. Clinicians performing videofluoroscopic swallowing studies should be familiar with both sides of the risk benefit equation in order to determine whether the study is medically justified. The intent of this article is to provide the necessary background for conversations about benefit and risk in videofluoroscopic swallowing studies.

Using an Automated Speech Recognition Approach to Differentiate Between Normal and Aspirating Swallowing Sounds Recorded from Digital Cervical Auscultation in Children

Use of machine learning to accurately detect aspirating swallowing sounds in children is an evolving field. Previously reported classifiers for the detection of aspirating swallowing sounds in children have reported sensitivities between 79 and 89%. This study aimed to investigate the accuracy of using an automatic speaker recognition approach to differentiate between normal and aspirating swallowing sounds recorded from digital cervical auscultation in children. We analysed 106 normal swallows from 23 healthy children (median 13 months; 52.1% male) and 18 aspirating swallows from 18 children (median 10.5 months; 61.1% male) who underwent concurrent videofluoroscopic swallow studies with digital cervical auscultation. All swallowing sounds were on thin fluids. A support vector machine classifier with a polynomial kernel was trained on feature vectors that comprised the mean and standard deviation of spectral subband centroids extracted from each swallowing sound in the training set. The trained support vector machine was then used to classify swallowing sounds in the test set. We found high accuracy in the differentiation of aspirating and normal swallowing sounds with 98% overall accuracy. Sensitivity for the detection of aspiration and normal swallowing sounds were 89% and 100%, respectively. There were consistent differences in time, power spectral density and spectral subband centroid features between aspirating and normal swallowing sounds in children. This study provides preliminary research evidence that aspirating and normal swallowing sounds in children can be differentiated accurately using machine learning techniques.

Infant aspiration and associated signs on clinical feeding evaluation

OBJECTIVES

Few studies have examined clinical signs of aspiration in infants <51 weeks post-menstrual age (PMA) for whom the laryngeal cough reflex is not fully developed. This retrospective study explored 1) the association between signs of aspiration on a clinical feeding evaluation (CFE) and/or comorbid conditions with aspiration (silent or overt) on a modified barium swallow study (MBS) for infants in this age range, 2) the association between lower respiratory infection (LRI) and aspiration on MBS, and 3) the sensitivity and specificity of detecting aspiration according to signs on CFE and the evaluating speech-language pathologist's (SLP) years of experience.

METHODS

A retrospective review of charts of patients with MBS completed January 1, 2012-December 31, 2014 was performed. Patients were included if they were <51-weeks PMA at the time of MBS and had a CFE conducted no more than seven days prior to the MBS. Patient age, comorbidities, and MBS and CFE details were collected. The impact of CFE findings, patient age, comorbid syndromes/associations, and aerodigestive diagnoses on the odds of demonstrating silent aspiration (SA) or overt aspiration during MBS with thin liquids was determined using logistic regression, and the sensitivity and specificity of CFE for identifying SA was calculated.

RESULTS

Results from 114 patients indicated that 46 (40 %) of the infants had SA and nine (8 %) had overt aspiration on MBS. Notable signs on CFEs were cough (36 %), oxygen desaturations (33 %), and chest congestion (32 %). On multiple regression analysis there was increased odds of SA on MBS with at least one clinical sign on CFE (OR: 24.3, p = 0.02), chronic lung disease, (OR: 18.2, p = 0.01), and airway abnormalities (OR: 2.94, p = 0.01). Cough on CFE was associated with increased odds of overt aspiration on MBS (OR: 5.69, p = 0.04). Neither SA nor overt aspiration were significantly associated with LRI. Sensitivity and specificity of CFE for correctly identifying the presence of SA were 98 % and 15 %, respectively; experience of the SLP was not a contributing factor.

CONCLUSION

Further study is required to determine if specific signs on CFE are predictive of aspiration.

Usefulness of the Modified Videofluoroscopic Dysphagia Scale in Evaluating Swallowing Function among Patients with Amyotrophic Lateral Sclerosis and Dysphagia

INTRODUCTION

The videofluoroscopic dysphagia scale (VDS) is used to predict the long-term prognosis of dysphagia among patients with the condition. Previously, a modified version of the VDS (mVDS) was established to overcome the relatively low inter-rater reliability of VDS, and was verified in patients with dysphagia, such as stroke patients. However, the validity of mVDS in patients with amyotrophic lateral sclerosis (ALS) has never been proved. Therefore, in this study, we attempted to seek the validity of the mVDS score in patients with ALS suffering from dysphagia.

METHOD

Data from the videofluoroscopic swallowing study (VFSS) of 34 patients with ALS and dysphagia were retrospectively collected. We investigated the presence of aspiration pneumonia and the selected feeding method based on the VFSS. We also evaluated the correlations between the mVDS and the selected feeding method, and between the mVDS and the presence of aspiration pneumonia. Multivariate logistic regression and receiver operating characteristic (ROC) analyses were performed during the data analysis.

RESULTS

In patients with ALS and dysphagia, the mVDS scores were statistically correlated with the selected feeding method (p < 0.05) and the presence of aspiration pneumonia (p < 0.05). In the ROC curve analysis, the area under the ROC curve values for the selected feeding method and the presence of aspiration pneumonia were 0.886 (95% confidence interval (CI), 0.730-0.969; p < 0.0001) and 0.886 (95% CI, 0.730-0.969; p < 0.0001), respectively.

CONCLUSION

The mVDS can be a useful tool for quantifying the severity of dysphagia and interpreting the VFSS findings in patients with ALS and dysphagia. However, further studies involving a more general population of patients with ALS are needed to elucidate a more accurate cut-off value for the allowance of oral feeding and the presence of aspiration pneumonia.

Radiation exposure in modified barium swallow studies

PURPOSE OF REVIEW

The modified barium swallow study (MBSS) is an X-ray examination of swallowing used to detect the presence and type impairment, aspiration risk, and to develop intervention plans. In this review, we will cover the use of ionizing radiation in MBSSs and review recent literature concerning radiation exposure and cancer risks to patients undergoing MBSSs. Lastly, we will discuss the clinical implications of these findings.

RECENT FINDINGS

Recent literature confirms that the MBSS is a low-dose examination and that reducing pulse rate negatively impacts diagnostic accuracy. Importantly, cancer risks to adults undergoing MBSSs were also reported to be low.

SUMMARY

An adult undergoing MBSS using a standardized, valid protocol, like the Modified Barium Swallow Impairment Profile (MBSImP), has low-radiation exposure and very low associated cancer risks. MBSSs should be used whenever relevant to adult patient care without undue concern regarding radiation exposure. Children also have low radiation exposure from MBSSs; however, cancer risks from that exposure remain unknown. Best practices in radiation safety must always be followed. Reducing pulse rates in the adult or pediatric population to reduce radiation exposure is not a valid strategy because of the resulting reduction in diagnostic accuracy.

Radiation Safety in Videofluoroscopic Swallowing Study: Systematic Review

Videofluoroscopic swallowing study (VFSS) is generally used to diagnose dysphagia and oropharyngeal aspiration during swallowing movement. Patients and bolus-feeding operators (such as occupational therapist and speech language pathologist) may undergo multiple VFSS procedure, placing them at risk for more radiation exposure due to increased scan time. The present study investigated the dose-area product, effective dose of various protocols, and summarized dose reports from various studies of VFSS. The PubMed database searched for relevant publications reporting radiation dose in the VFSS procedure. 13 articles were selected to be reviewed. This systematic review involved 13 peer-reviewed articles that reported the specific dose of the VFSS procedure. The articles were categorized into three types: operator radiation dose, adult patient radiation dose, and pediatric radiation dose. The operator dose reports showed that the operators' scattering exposure, equivalent dose (across the whole body, eyes, and hands), and annual effective dose were significantly lower than the annual dose limit of 20 mSv. Both adult and pediatric patient dose reports showed that the effective dose, which was estimated from recorded dose-area product, was significantly lower than the annual background exposure of 2.4 mSv in various protocols. The present literature review suggested that the radiation dose of VFSS by modified barium swallowing is acceptable in both operators and patients. However, various radiation protection strategies should be conducted during the procedure to reduce the risk of stochastic effect.