A Ten-Year Retrospective Cohort Study on Neck Collar Immobilization in Trauma Patients with Head and Neck Injuries.

Background and Objectives: In the context of prehospital care, spinal immobilization is commonly employed to maintain cervical stability in head and neck injury patients. However, its use in cases of unclear consciousness or major trauma patients is often precautionary, pending the exclusion of unstable spinal injuries through appropriate diagnostic imaging. The impact of prehospital C-spinal immobilization in these specific patient populations remains uncertain. Materials and Methods: We conducted a retrospective cohort study at Taipei Tzu Chi Hospital from January 2009 to May 2019, focusing on trauma patients suspected of head and neck injuries. The primary outcome assessed was in-hospital mortality. We employed multivariable logistic regression to investigate the relationship between prehospital C-spine immobilization and outcomes, while adjusting for various factors such as age, gender, type of traumatic brain injury, Injury Severity Score (ISS), Revised Trauma Score (RTS), and activation of trauma team. Results: Our analysis encompassed 2733 patients. Among these, patients in the unclear consciousness group (GCS ≤ 8) who underwent C-spine immobilization exhibited a higher mortality rate than those without immobilization. However, there was no statistically significant difference in mortality among patients with alert consciousness (GCS > 8). Multivariable logistic regression analysis revealed that advanced age (age ≥ 65), unclear consciousness (GCS ≤ 8), major traumatic injuries (ISS ≥ 16 and RTS ≤ 7), and the use of neck collars for immobilization (adjusted OR: 1.850, 95% CI: 1.240-2.760, p = 0.003) were significantly associated with an increased risk of mortality. Subgroup analysis indicated that C-spine immobilization was significantly linked to an elevated risk of mortality in older adults (age ≥ 65), patients with unclear consciousness (GCS ≤ 8), those with major traumatic injuries (ISS ≥ 16 and RTS ≤ 7), and individuals in shock (shock index > 1). Conclusions: While our findings do not advocate for the complete abandonment of neck collars in all suspected head and neck injury patients, our study suggests that prehospital cervical and spinal immobilization should be applied more selectively in certain head and neck injury populations. This approach is particularly relevant for older individuals (age ≥ 65), those with unclear consciousness (GCS ≤ 8), individuals experiencing major traumatic injuries (ISS ≥ 16 or RTS ≤ 7), and patients in a state of shock (shock index ≥ 1). Our study employs a retrospective cohort design, which may introduce selection bias. Therefore, in the future, there is a need for confirmation of our results through a two-arm randomized controlled trial (RCT) arises, as this design is considered ideal for addressing this issue.

Erratum: Noiseless variable-pressure neck chamber device to assess the carotid baroreflex function.

[This corrects the article DOI: 10.3389/fphys.2020.613311.].

Neck Collar Assessment for People Living With Motor Neuron Disease: Are Current Outcome Measures Suitable?

A majority of people living with motor neuron disease (MND) experience weakness of the neck and as a result, experience head drop. This exacerbates problems with everyday activities (eating, talking, breathing, etc). Neck collars are often used to support head drop; however, these are typically designed for prehospitalization settings to manage and brace the cervical region of the spine. As a result, it has been recorded that people living with MND often reject these collars for a variety of reasons but most notably because they are too restricting. The current standardized outcome measures (most notably restricting cervical range of motion) used for neck collars are summarized herein along with whether they are suitable for a bespoke neck collar specifically designed for people living with MND.

High School Sports-Related Concussion and the Effect of a Jugular Vein Compression Collar: A Prospective Longitudinal Investigation of Neuroimaging and Neurofunctional Outcomes.

Sports-related concussion (SRC) can exert serious acute and long-term consequences on brain microstructure, function, and behavioral outcomes. We aimed to quantify the alterations in white matter (WM) microstructure and global network organization, and the decrements in behavioral and cognitive outcomes from pre-season to post-concussion in youth athletes who experienced SRC. We also aimed to evaluate whether wearing a jugular compression neck collar, a device designed to mitigate brain "slosh" injury, would mitigate the pre-season to post-concussion alterations in neuroimaging, behavioral, and cognitive outcomes. A total of 488 high school football and soccer athletes (14-18 years old) were prospectively enrolled and assigned to the non-collar group (n = 237) or the collar group (n = 251). The outcomes of the study were the pre-season to post-concussion neuroimaging, behavioral, and cognitive alterations. Forty-six participants (non-collar: n = 24; collar: n = 22) were diagnosed with a SRC during the season. Forty of these 46 athletes (non-collar: n = 20; collar: n = 20) completed neuroimaging assessment. Significant pre-season to post-concussion alterations in WM microstructural integrity and brain network organization were found in these athletes (corrected p < 0.05). The alterations were significantly reduced in collar-wearing athletes compared to non-collar-wearing athletes (corrected p < 0.05). Concussion and collar main effects were identified for some of the behavioral and cognitive outcomes, but no collar by SRC interaction effects were observed in any outcomes. In summary, young athletes exhibited significant WM microstructural and network organizational, and cognitive alterations following SRC. The use of the jugular vein compression collar showed promising evidence to reduce these alterations in high school contact sport athletes.

Primary treatment of atlantoaxial rotatory fixation in children: a multicenter, retrospective series of 125 cases.

OBJECTIVE: The primary treatment for atlantoaxial rotatory fixation (AARF) remains controversial. The aim of this study was to investigate the primary treatment for AARF and create an algorithm for primary treatment. METHODS: The authors analyzed the data of 125 pediatric patients at four medical institutions from April 1989 to December 2018. The patients were reported to have neck pain, torticollis, and restricted neck range of motion and were diagnosed according to the Fielding classification as type I or II. As a primary treatment, 88 patients received neck collar fixation, and 28 of these patients did not show symptom relief and required Glisson traction. Thirty-seven patients were primarily treated with Glisson traction. In total, 65 patients, including neck collar treatment failure patients, underwent Glisson traction in hospitals. RESULTS: The success rate of treatment was significantly higher in the Glisson traction group (97.3%) than in the neck collar fixation group (68.2%) (p = 0.0001, Wilcoxon test). In the neck collar effective group, Fielding type I was more predominant (p = 0.0002, Wilcoxon test) and the duration from onset to the first visit was shorter (p = 0.02, Wilcoxon test) than that in the neck collar ineffective group. Using multivariate logistic regression analysis with the above items, the authors generalized from the estimated formula: logit [p(success group by neck collar fixation group)|duration from onset to the first visit (x1), Fielding type (x2)] = 0.4(intercept) - 0.15x1 + 1.06x2, where x1 is the number of days and x2 = 1 (for Fielding type I) or -1 (for Fielding type II). In cases for which the score is a positive value, the neck collar should be chosen. Conversely, in cases for which the score is a negative value, Glisson traction should be the first choice. CONCLUSIONS: According to this formula, in patients with Fielding type I AARF, neck collar fixation should be allowed only if the duration from onset is ≤ 10 days. In patients with Fielding type II, because the score would be a negative value, Glisson traction should be performed as the primary treatment.

Altered Functional and Structural Connectomes in Female High School Soccer Athletes After a Season of Head Impact Exposure and the Effect of a Novel Collar.

Background: Characterization of, and evaluation of strategies to mitigate, the effects of sub-concussive impacts (SCI) on brain structure and function are crucial to understanding potential long-term neurological risks associated with sports participation. Objectives: To evaluate the efficacy of a jugular vein compression collar for preserving functional and structural measures of brain network organization in a cohort of female high school soccer players throughout a season of competitive play. Methods: Athletes were assigned to a collar (N = 72) or non-collar (N = 56) group before engaging in a season of play, during which head impact data were recorded via accelerometer for every practice and competition. Participants completed neuroimaging sessions before and following the season. A graph theoretical framework was applied to the functional and structural connectivity measures computed from resting state functional magnetic resonance imaging (rs-fMRI) and diffusion tensor imaging (DTI) data. Results: Non-collar-wearing athletes exhibited significantly increased rs-fMRI-derived global clustering coefficients (p = 0.032) and DTI-derived modularity (p = 0.042), compared to collar-wearing athletes. No longitudinal changes in any graph measures were observed for the collar group (p > 0.05). Conclusion: The observed increase in graph measures in the non-collar group is congruent with previous studies of SCI and is similar to graph theoretical studies of traumatic brain injury. The absence of alterations in graph metrics in the collar group indicates a potential ameliorating effect of the collar device against network reorganization, in line with previous literature.

Noiseless Variable-Pressure Neck Chamber Device to Assess the Carotid Baroreflex Function.

Background: The blood pressure responses to baroreflex perturbations can be assessed only using the variable-pressure neck chamber technique. However, the application of this approach in hospital environments is limited owing to the loud noise emitted during its operation. This study was aimed at developing a noiseless neck suction chamber device (NCD) that could stimulate the baroreceptors located in the carotid sinus in humans. Methods: A non-invasive device was developed to pressurize the carotid arteries externally. A microcontroller with a computer interface and neck chamber (3D-printed) was used. The anatomical neck chamber was fitted on six healthy, young, asymptomatic participants (five men; 32 ± 6 year), who were normotensive, nonsmoking, in sinus rhythm, free of known cardiovascular or metabolic diseases, and not consuming any acute or chronic medications. A suction of -60 mmHg was applied for 5 s, and the corresponding data were recorded. Before each study visit, the participants were instructed to abstain from caffeine, alcohol, and strenuous exercise for 12-24 h. Results: In all the trials, a significant reflex bradycardia (-10 ± 2 bpm) and depressor response (-15 ± 4 mmHg) to neck suction were observed, consistent with the results in the literature. The neck chamber device operated noiselessly [sound pressure level (SPL) of 34.3 dB] compared to a regular vacuum-cleaner-based system (74.6 dB). Conclusion: Using the proposed approach, consistent blood pressure and heart rate responses to carotid baroreflex hypertensive stimuli could be recorded, as in previous studies conducted using neck collar devices. Furthermore, the neck chamber device operated noiselessly and can thus be applied in hospital environments.

Impact of Low-Level Blast Exposure on Brain Function after a One-Day Tactile Training and the Ameliorating Effect of a Jugular Vein Compression Neck Collar Device.

Special Weapons and Tactics (SWAT) personnel who conduct breacher exercises are at risk for blast-related head trauma. We aimed to investigate the potential impact of low-level blast exposure during breacher training on the neural functioning of working memory and auditory network connectivity. We also aimed to evaluate the effects of a jugular vein compression collar, designed to internally mitigate slosh energy absorption, preserving neural functioning and connectivity, following blast exposure. A total of 23 SWAT personnel were recruited and randomly assigned to a non-collar (n = 11) and collar group (n = 12). All participants completed a 1-day breacher training with multiple blast exposure. Prior to and following training, 18 participants (non-collar, n = 8; collar, n = 10) completed functional magnetic resonance imaging (fMRI) of working memory using N-Back task; 20 participants (non-collar, n = 10; collar, n = 12) completed resting-state fMRI. Key findings from the working memory analysis include significantly increased fMRI brain activation in the right insular, right superior temporal pole, right inferior frontal gyrus, and pars orbitalis post-training for the non-collar group (p < 0.05, threshold-free cluster enhancement corrected), but no changes were noted for the collar group. The elevation in fMRI activation in the non-collar group was found to correlate significantly (n = 7, r = 0.943, p = 0.001) with average peak impulse amplitude experienced during the training. In the resting-state fMRI analysis, significant pre- to post-training increase in connectivity between the auditory network and two discrete regions (left middle frontal gyrus and left superior lateral occipital/angular gyri) was found in the non-collar group, while no change was observed in the collar group. These data provided initial evidence of the impact of low-level blast on working memory and auditory network connectivity as well as the protective effect of collar on brain function following blast exposure, and is congruent with previous collar findings in sport-related traumatic brain injury.

Postoperative Rigid Cervical Collar Leads to Less Axial Neck Pain in the Early Stage After Open-Door Laminoplasty-A Single-Blinded Randomized Controlled Trial.

BACKGROUND: Cervical collars are used after laminoplasty to protect the hinge opening, reduce risks of hinge fractures, and avoid spring-back phenomena. However, their use may lead to reduced range of motion and worse neck pain. OBJECTIVE: To investigate the clinical, radiological, and functional outcomes of patients undergoing single-door laminoplasty with or without collar immobilization. METHODS: This was a prospective, parallel, single-blinded randomized controlled trial. Patients underwent standardized single-door laminoplasty with mini-plates for cervical myelopathy and were randomly allocated into 2 groups based on the use of collar postoperatively. Clinical assessments included cervical range of motion, axial neck pain (VAS [visual analogue scale]), and objective scores (short-form 36-item, neck disability index, and modified Japanese Orthopaedic Association). All assessments were performed preoperatively and at postoperative 1, 2, 3, and 6 wk, and 3, 6, and 12 mo. Comparative analysis was performed via analysis of variance adjusted by baseline scores, sex, and age as covariates. RESULTS: A total of 35 patients were recruited and randomized to collar use (n = 16) and without (n = 19). There were no dropouts or complications. There were no differences between groups at baseline. Subjects had comparable objective scores and range of motion at postoperative time-points. Patients without collar use had higher VAS at postoperative 1 wk (5.4 vs 3.5; P = .038) and 2 wk (3.5 vs 1.5; P = .028) but subsequently follow-up revealed no differences between the 2 groups. CONCLUSION: The use of a rigid collar after laminoplasty leads to less axial neck pain in the first 2 wk after surgery. However, there is no additional benefit with regards to range of motion, quality of life, and complication risk.

Characteristic "neck collar" injuries in Australian sea lions (Neophoca cinerea) caused by marine debris.

An adult male Australian sea lion (Neophoca cinerea) presented with a deep, almost circumferential, incised wound around the neck caused by a noose formed by a single strand of green nylon rope. The wound extended 4-5 cm deeply through the skin and blubber into skeletal muscle, predominantly on the dorsal surface and left side, but had not involved the airway or major vessels. The edges of the wound were sharply incised and oozing blood with a granulating infected base. The rope was removed and the wound debrided of necrotic tissues and irrigated with disinfectant. Antibiotic and rehydration therapy were successful and the seal was released after 2 weeks of treatment. Entanglement injuries such as "neck collars" have characteristic features, are increasing in incidence and often have lethal outcomes. This type of injury may significantly impact upon populations of pinnipeds in the wild.

Superficial Chronic Ulcerative Dermatitis (SCUD) in Psittacine Birds: Review of 11 Cases (2008-2016).

We reviewed 11 cases of superficial chronic ulcerative dermatitis (SCUD) in psittacine birds that presented to an exotic animal practice over an 8-year period. African grey parrots ( Psittacus erithacus) were overrepresented, accounting for 55% of SCUD-affected birds. All affected birds were hand-reared pets and bonded strongly to their owners. In all cases, fungal culture results were negative. The most commonly cultured bacteria were Enterobacter cloacae (27%), followed by Escherichia coli, and Staphylococcus aureus (both 18%). An underlying cause of behavioral self-mutilation with secondary infection of dermatitis lesions by opportunistic bacteria was suspected in 10 of 11 cases. The axillae were the most common anatomic sites affected (45%). In two cases, more than one site was affected concurrently. Mean age of birds affected was 11.4 years. Two birds had suffered from SCUD previously, with 1 bird having suffered from 3 previous episodes and was euthanized as a result. All birds were treated with systemic antibiotics, topical antibacterial preparations, and systemic nonsteroidal anti-inflammatory drugs. A neck collar was applied in all cases. Median time to clinical resolution was 2 months (range, 1-21 months). Excluding the bird that was euthanized, all birds showed a positive response to treatment.

Mild Jugular Compression Collar Ameliorated Changes in Brain Activation of Working Memory after One Soccer Season in Female High School Athletes.

Recent neuroimaging studies have suggested that repetitive subconcussive head impacts, even after only one sport season, may lead to pre- to post-season structural and functional alterations in male high school football athletes. However, data on female athletes are limited. In the current investigation, we aimed to (1) assess the longitudinal pre- to post-season changes in functional MRI (fMRI) of working memory and working memory performance, (2) quantify the association between the pre- to post-season change in fMRI of working memory and the exposure to head impact and working memory performance, and (3) assess whether wearing a neck collar designed to reduce intracranial slosh via mild compression of the jugular veins can ameliorate the changes in fMRI brain activation observed in the female high school athletes who did not wear collars after a full soccer season. A total of 48 female high school soccer athletes (age range: 14.00-17.97 years) were included in the study. These athletes were assigned to the non-collar group (n = 21) or to the collar group (n = 27). All athletes undewent MRI at both pre-season and post-season. In each session, a fMRI verbal N-Back task was used to engage working memory. A significant pre- to post-season increase in fMRI blood oxygen level dependent (BOLD) signal was demonstrated when performing the N-back working memory task in the non-collar group but not in the collar group, despite the comparable exposure to head impacts during the season between the two groups. The collar group demonstrated significantly smaller pre- to post-season change in fMRI BOLD signal than the non-collar group, suggesting a potential protective effect from the collar device. Significant correlations were also found between the pre- to post-season increase in fMRI brain activation and the decrease in task accuracy in the non-collar group, indicating an association between the compensatory mechanism in underlying neurophysiology and the alteration in the behavioral outcomes.

White matter alterations over the course of two consecutive high-school football seasons and the effect of a jugular compression collar: A preliminary longitudinal diffusion tensor imaging study.

The cumulative effects of repetitive subclinical head impacts during sports may result in chronic white matter (WM) changes and possibly, neurodegenerative sequelae. In this pilot study, we investigated the longitudinal WM changes over the course of two consecutive high-school football seasons and explored the long-term effects of a jugular vein compression collar on these WM alterations. Diffusion tensor imaging data were prospectively collected both pre- and postseason in the two consecutive seasons. Participants were assigned into either collar or noncollar groups. Tract-based spatial statistics (TBSS) approach and region of interest-based approach were used to quantify changes in WM diffusion properties. Despite comparable exposure to repetitive head impacts, significant reductions in mean, axial, and/or radial diffusivity were identified in Season 1 in multiple WM regions in the noncollar group but not in the collar group. After an 8- to 9-month long off-season, these changes observed in the noncollar group partially and significantly reversed but also remained significantly different from the baseline. In Season 2, trend level WM alterations in the noncollar group were found but located in spatially different regions than Season 1. Last, the WM integrity in the collar group remained unchanged throughout the four time points. In conclusion, we quantitatively assessed the WM structural changes and partial reversal over the course of two consecutive high-school football seasons. In addition, the mitigated WM alterations in athletes in the collar group might indicate potential effect of the collar in ameliorating the changes against repetitive head impacts. Hum Brain Mapp 39:491-508, 2018. © 2017 Wiley Periodicals, Inc.

A comfort assessment of existing cervical orthoses.

PURPOSE: Identify location and intensity of discomfort experienced by healthy participants wearing cervical orthoses. METHOD: Convenience sample of 34 healthy participants wore Stro II, Philadelphia, Headmaster, and AspenVista® cervical orthoses for four-hour periods. Participants reported discomfort level (scale 0-6) and location. RESULTS: Participants reported mean discomfort for all orthoses over the four-hour test between 'a little discomfort' and 'very uncomfortable' (mean discomfort score = 1.64, SD = 1.50). Seven participants prematurely stopped tests due to pain and six reported maximum discomfort scores. Significant linear increase in discomfort with duration of wear was found for all orthoses. Significantly less discomfort was reported with Stro II than Headmaster and Philadelphia. Age correlated with greater perceived discomfort. Orthoses differed in the location discomfort was experienced. CONCLUSION: Existing cervical orthoses cause discomfort influenced by design and duration of wear with orthoses' design the more significant factor. This work informed the design of a new orthosis and future orthoses developments. Practitioner Summary: The purpose of this study was to gain greater knowledge about the discomfort caused by wearing of existing neck orthoses in order to inform the design and development of a new neck orthosis. This study gathers empirical data from a surrogate population and concludes that orthosis design is more influential than the duration of wear.

Endotracheal intubation using semi-rigid optical stylet in simulated difficult airways of high grade modified Cormack and Lehane laryngeal views

BACKGROUND: Endotracheal intubation in patients with compromised cervical vertebrae and limited mouth opening is challenging, however, there are still limited options available. Among devices used for managing difficult airways, the Clarus Video System (CVS) might have considerable promise due to its semi-rigid tip. We evaluated the performance of CVS in patients with simulated difficult airways. METHODS: Philadelphia cervical collars were applied to 74 patients undergoing general anesthesia. The degree of simulated difficult airway was assessed by observing laryngeal view using McCoy laryngoscope; modified Cormack and Lehane grade (MCL) ≥ 3a (high-grade group, n = 38) or ≤ 2b (low-grade group, n = 36). Subsequently, patients were intubated using CVS by a blinded practitioner. We evaluated total time to intubation, intubation success rate, and conditions of intubation. RESULTS: Intubation took significantly longer time for the high-grade group than that for the low-grade group (38.2 ± 25.9 seconds vs. 27.9 ± 6.2 seconds, time difference 10.3 seconds, 95% confidence interval: 1.4–19.2 seconds, P < 0.001). However, CVS provided similar high intubation success rates for both groups (97.4% for the high-grade and 100% for the low-grade group). During intubation, visualization of vocal cords and advancement into the glottis for the high-grade group were significantly more difficult than those for the low-grade group. CONCLUSIONS: Although intubation took longer for patients with higher MCL laryngeal view grade, CVS provided high intubation success rate for patients with severely restricted neck motion and mouth opening regardless of its MCL laryngeal view grade.

Neck Collar with Mild Jugular Vein Compression Ameliorates Brain Activation Changes during a Working Memory Task after a Season of High School Football.

Emerging evidence indicates that repetitive head impacts, even at a sub-concussive level, may result in exacerbated or prolonged neurological deficits in athletes. This study aimed to: 1) quantify the effect of repetitive head impacts on the alteration of neuronal activity based on functional magnetic resonance imaging (fMRI) of working memory after a high school football season; and 2) determine whether a neck collar that applies mild jugular vein compression designed to reduce brain energy absorption in head impact through "slosh" mitigation can ameliorate the altered fMRI activation during a working memory task. Participants were recruited from local high school football teams with 27 and 25 athletes assigned to the non-collar and collar group, respectively. A standard N-Back task was used to engage working memory in the fMRI at both pre- and post-season. The two study groups experienced similar head impact frequency and magnitude during the season (all p > 0.05). fMRI blood oxygen level dependent (BOLD) signal response (a reflection of the neuronal activity level) during the working memory task increased significantly from pre- to post-season in the non-collar group (corrected p < 0.05), but not in the collar group. Areas displaying less activation change in the collar group (corrected p < 0.05) included the precuneus, inferior parietal cortex, and dorsal lateral prefrontal cortex. Additionally, BOLD response in the non-collar group increased significantly in direct association with the total number of impacts and total g-force (p < 0.05). Our data provide initial neuroimaging evidence for the effect of repetitive head impacts on the working memory related brain activity, as well as a potential protective effect that resulted from the use of the purported brain slosh reducing neck collar in contact sports.

Surgical approach and technique in retrosternal goiter: Case report and review of the literature.

BACKGROUND: Retrosternal goiter is defined as a thyroid mass of which more than 50% is located below the thoracic inlet. The aim of this study is to assess the retrosternal goiter surgically approach through a neck incision and analyze the surgical technique. CASE PRESENTATION: The case reported by us used a single neck collar-shaped incision for huge retrosternal goiter with good outcome. The patient was surgically treated through a neck incision without the need for sternotomy or lateral thoracotomy. We did not observe definitive lesions in the inferior laryngeal nerve or definitive hypoparathyroidism. CONCLUSIONS: Patients with retrosternal goiter can be safely treated surgically through a single neck incision, which is less trauma and recovery quickly.

Effect of a neck collar on upper airway size in children sedated with propofol-midazolam combination during magnetic resonance imaging.

INTRODUCTION: Propofol and midazolam are widely used for pediatric magnetic resonance imaging (MRI) sedation. Increasing depth of sedation may be associated with airway obstruction. A neck collar supporting the mandible and maintaining the head in slight extension may be beneficial in maintaining airway patency. AIM OF THE STUDY: Primary aim: To assess upper airway size with and without a neck collar during pediatric MRI sedation with propofol-midazolam. Secondary aim: To evaluate complications encountered during the procedure. MATERIALS AND METHODS: Sixty patients aged 2-4 years scheduled for MRI of the brain were selected. They were sedated with intramuscular midazolam 0.1 mg·kg(-1) 30 min before the procedure. Patients were sedated with i.v. propofol 1 mg·kg(-1) and continued with 50-100 µg·kg(-1) ·min(-1) . T1 3D fast-field echo axial sequence from the nasopharyngeal roof to subglottic region was taken with and without application of a neck collar. Airway dimensions were measured and analyzed at the base of the tongue, soft palate, and at the epiglottis. RESULTS: At the base of the tongue and soft palate, the cross-sectional area (CSA) and the anteroposterior diameter of the airway were respectively statistically significantly higher when the neck collar was applied. The CSA at the epiglottis was significantly less with application of the neck collar. Complications were not significantly different between the two sequences. CONCLUSION: Application of a soft neck collar in children aged 2-4 years may enhance the retropalatal and retroglossal airway dimensions during pediatric sedation in the supine position.