Real-Time Dynamic Imaging Study of Normal Pharyngolaryngeal Structures During Barium Swallow (GLAM-III) (GLAM-III)

Observational Imaging Study on Real-Time Dynamic Changes of Normal Pharyngolaryngeal Structures During Barium Swallow in Patients Undergoing Routine Barium Meal Examination

The integrity and functional stability of pharyngolaryngeal anatomical structures are critical for airway management, and the dynamic changes of key structures (e.g., pyriform sinus, cricoid cartilage lamina) during swallowing directly relate to the design and clinical safety of laryngeal masks. This observational study aims to investigate the real-time dynamic changes and physiological movement patterns of normal pharyngolaryngeal structures during barium swallow using routine barium meal examination imaging. The findings will provide anatomical and physiological evidence for optimizing laryngeal mask design and improving its anatomical fit with the pharynx and larynx.

Study Overview

• Status: Recruiting
• Conditions: Barium Meal Examination

Detailed Description

After approval by the Ethics Committee of Zhejiang Cancer Hospital (Approval Number: IRB-2025-1096(IIT)), this study will be registered on ClinicalTrials.gov prior to participant enrollment. Given that the study only utilizes de-identified imaging data from routine barium meal examinations (no additional procedures or interventions for participants), informed consent is exempted as approved by the Ethics Committee. The study is planned to be conducted from August 2025 to October 2025.

Eligible participants are patients undergoing routine barium meal examinations at Zhejiang Cancer Hospital, meeting the inclusion criteria (18-75 years old, no pharyngolaryngeal surgery/trauma/congenital malformation, no swallowing dysfunction, unobstructed oropharyngeal-esophageal pathway, etc.) and excluding those with contraindications (e.g., goiter compressing pharyngolaryngeal structures, barium allergy).

Barium Swallow Examination Procedure:

All procedures follow the standard clinical protocol for barium meal examinations, with no additional radiation exposure or burden on participants:

Static Imaging (Resting State): Participants assume a standing position. A digital X-ray machine (Shimadzu Uni-vision) is used to obtain static images of the pharyngolaryngeal region, recording the baseline anatomical positions of the pyriform sinus, cricoid cartilage lamina, and esophageal inlet.

Dynamic Imaging (Swallowing State): Participants are instructed to swallow 5ml, 10ml, 20ml, and 40ml of medical barium sulfate suspension (concentration: 160-200% W/V) sequentially. During swallowing, a dynamic fluoroscopic imaging system is activated (frame rate: 15 frames/second) to continuously record the entire process of barium passing from the oropharynx through the larynx to the esophagus (each swallowing event lasts approximately 5-10 seconds). Each participant repeats the swallowing action 4-5 times, and the clearest dynamic image sequence is selected for subsequent analysis.

Data Collection and Analysis:

Image analysis software is used for frame-by-frame parsing of dynamic images. Key anatomical structures (pyriform sinus boundaries, anterior edge of the cricoid cartilage lamina, esophageal inlet center) are labeled, and coordinate positioning technology is applied to analyze the following parameters:

Displacement and angle changes of pharyngolaryngeal structures from resting state to peak swallowing phase; Preferred pathway of barium through the oropharynx (unilateral pyriform sinus, bilateral pyriform sinuses, or central region of the cricoid cartilage lamina); Retention time of barium in the pyriform sinus and its passing speed; Expansion amplitude of the pyriform sinus and displacement distance of the cricoid cartilage lamina during swallowing

• Study Type: Observational
• Enrollment (Estimated): 3

Contacts and Locations

• Study Contact: Name: Jiangling Wang, Ph. D; Phone Number: +86 571 88122106; Email: wangjl@zjcc.org.cn
• Study Contact Backup: Name: Xiaochun Jin, M.D; Phone Number: +86 571 88122564; Email: ec@zjcc.org.cn

Study Locations

• China
  • Zhejiang
    • Hangzhou, Zhejiang, China, 310022
      • Recruiting
      • Jiangling Wang
      • Principal Investigator: Jiangling Wang, Dr.
      • Contact: Jiangling Wang, Dr.; Phone Number: +8615168373331; Email: wangjl@zjcc.org.cn

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: N/A

• Sampling Method: Non-Probability Sample

Study Population

Patient scheduled to take barium meal examination

Description

Inclusion Criteria:

• Aged 18-75 years;
• No history of pharyngolaryngeal surgery, trauma, or congenital malformation;
• No swallowing dysfunction, pharyngolaryngeal inflammation, or neurological diseases affecting swallowing;
• No recent use of drugs that affect muscle function (e.g., muscle relaxants, anticholinergics);
• Barium meal examination confirms unobstructed oropharyngeal-esophageal pathway;
• Normal pharyngolaryngeal anatomical structure (confirmed by preliminary imaging review);
• Scheduled to undergo routine barium meal examination at Zhejiang Cancer Hospital for clinical diagnosis.

Exclusion Criteria:

• Presence of diseases that may compress pharyngolaryngeal structures (e.g., goiter, mediastinal mass);
• Allergy to barium sulfate or other components of the barium suspension.

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Real-time dynamic changes of pharyngolaryngeal structures during swallowing	Measurement of displacement distance of the cricoid cartilage lamina, expansion amplitude of the pyriform sinus, and movement trajectory of the esophageal inlet during swallowing (assessed via dynamic fluoroscopic imaging).	From the initiation of the barium swallow to the complete passage of the bolus through the upper esophageal sphincter, as assessed under videofluoroscopy (an average of 15 minutes per participant).

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Proportion of participants with consistent instrument insertion pathway and barium's preferred pathway (pyriform sinus)	Analysis of the consistency between the barium's preferred pathway (pyriform sinus) and the insertion pathway of laryngeal mask-related instruments, to explain the anatomical fit differences among three laryngeal mask designs (LMA Supreme, I-gel, GMA-Tulip).	From the initiation of the barium swallow to the complete passage of the bolus through the upper esophageal sphincter, as assessed under videofluoroscopy (an average of 15 minutes per participant).

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
Barium flow speed through the oropharynx	The speed of barium flow through the oropharyngeal region, measured by videofluoroscopic swallowing study. The speed will be calculated by tracking the movement of the barium bolus head between two predefined anatomical points (e.g., the pyriform sinus and the lower edge of the cricoid cartilage) and reported in millimeters per second (mm/s)	From the initiation of the barium swallow to the complete passage of the bolus through the upper esophageal sphincter, as assessed under videofluoroscopy (an average of 15 minutes per participant).
Preferred pathway of barium flow	The primary anatomical pathway of the barium bolus as it passes the laryngeal inlet, assessed by videofluoroscopy. The pathway will be categorized as either passing through the pyriform sinuses or through other channels (e.g., directly over the arytenoids). The result will be reported as the proportion (percentage) of participants with barium flow primarily through the pyriform sinuses.	From the initiation of the barium swallow to the complete passage of the bolus through the upper esophageal sphincter, as assessed under videofluoroscopy (an average of 15 minutes per participant).
Displacement of the cricoid cartilage lamina during barium swallow	The extent of posterior-inferior displacement of the cricoid cartilage lamina during the pharyngeal phase of swallowing, measured on lateral videofluoroscopic images. The displacement will be quantified as the vertical distance (in millimeters) from the resting position of the cricoid cartilage to its maximum displaced position.	From the initiation of the barium swallow to the complete passage of the bolus through the upper esophageal sphincter, as assessed under videofluoroscopy (an average of 15 minutes per participant).

Collaborators and Investigators

• Sponsor: Zhejiang Cancer Hospital
• Investigators: Study Chair: Pingbo Xu, Ph. D, Zhejiang Cancer Hospital

Study record dates

Study Major Dates

• Study Start (Actual): September 10, 2025
• Primary Completion (Estimated): December 30, 2025
• Study Completion (Estimated): December 30, 2025

Study Registration Dates

• First Submitted: September 21, 2025
• First Submitted That Met QC Criteria: November 23, 2025
• First Posted (Estimated): December 4, 2025

Study Record Updates

• Last Update Posted (Estimated): December 4, 2025
• Last Update Submitted That Met QC Criteria: November 23, 2025
• Last Verified: November 1, 2025

More Information

Terms related to this study

• Keywords: Barium Swallow; Pharyngolaryngeal Dynamic Changes; Pyriform Sinus; Cricoid Cartilage Lamina; Laryngeal Mask Design
• Other Study ID Numbers: IRB-2025-1096（IIT）

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No