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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Date data sharing statement initially provided
Date results information initially provided
Type of registration
Retrospectively registered

Titles & IDs
Public title
Use of novel device in the endoscopic treatment of Zenker's Diverticulum patients
Scientific title
Functional Lumen Imaging Probe demonstrates reduced cricopharyngeal distensibility and myotomy-induced improvement in Zenker’s Diverticulum patients
Secondary ID [1] 300800 0
Nil known
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Zenker diverticulum 316672 0
Condition category
Condition code
Oral and Gastrointestinal 314913 314913 0 0
Other diseases of the mouth, teeth, oesophagus, digestive system including liver and colon

Study type
Patient registry
Target follow-up duration
Target follow-up type
Description of intervention(s) / exposure
FLIP (functional lumen imaging probe) measures intestinal distensibility measurements. It has been used in a variety of clinical applications, and has previously been shown to discriminate outcomes from treatment of other oesophageal pathologies including achalasia and oesophageal strictures.
At our facility, FLIP measurements were performed pre- and post-therapeutic endoscopy procedures for dysphagic patients as part of standard care. This includes Zenker patients as well as patients with benign oesophageal strictures and achalasia.
For Zenker patients as relevant to our study, FLIP measurements will be performed during flexible endoscopy cricopharyngeal myotomy. Measurements will be performed by a senior gastroenterologist with expertise in oesophageal pathologies and advanced endoscopic techniques. Patients will be anaesthetised during the procedure by an anaesthesiologist(as is standard for endoscopic myotomy) and FLIP measurements will be taken immediately pre- and post-myotomy. FLIP measurements add approximately 10 minutes to procedure length, and will be performed as a single assessment during the procedure.
Intervention code [1] 317122 0
Not applicable
Comparator / control treatment
A historical control group was used. Our facility prospectively maintains data on distensibility measurements. Non-dysphagic patients were identified who had presented for review at our outpatient clinic and had distensibility measurements taken during routine diagnostic gastroscopy. These patients were screened for and data collected between February 2012 and February 2015.
Control group

Primary outcome [1] 323228 0
Cricopharyngeal distensibility as assessed by FLIP measurements.
Timepoint [1] 323228 0
Measurements will be taken at the time of gastroscopy for both groups. For the Zenker's diverticulum patients, FLIP measurements will be performed immediately before and after endoscopy myotomy. For the control group, measurements will be performed on completion of the diagnostic gastroscopy.
Secondary outcome [1] 381231 0
Clinical assessment of symptom severity (using modified Dakkak and Bennett scale)

Timepoint [1] 381231 0
Symptoms will be assessed pre-procedure and then again at 1 month post-myotomy.

Secondary outcome [2] 381232 0
Pre-operative and post-operative diverticulum size (classified using the Morton & Bartley classification system on the basis of barium swallow studies)
Timepoint [2] 381232 0
Diverticulum size will be assessed pre-procedure then at 1 month post-myotomy.
Secondary outcome [3] 381233 0
Procedural time measured from time of anaesthesia commencement to cessation. This was determined from routinely collected endoscopy suite documentation of time in/time out.
Timepoint [3] 381233 0
At completion of gastroscopy.
Secondary outcome [4] 381234 0
Adverse events including major (e.g. perforation, bleeding requiring transfusion, sepsis) and minor (e.g. pain, minor bleeding). These will be assessed through medical records.
Timepoint [4] 381234 0
Adverse events are screened for during routine follow up of patients up to 12 months following procedure.

Key inclusion criteria
Treatment naive Zenker's diverticulum patients undergoing flexible endoscopic cricopharyngeal myotomy
Minimum age
18 Years
Maximum age
No limit
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Patients without radiologically proven presence of Zenker diverticulum.
Patients who have previously had endoscopic or surgical treatment of Zenker diverticulum

Study design
Statistical methods / analysis

Recruitment status
Date of first participant enrolment
Date of last participant enrolment
Date of last data collection
Sample size
Accrual to date
Recruitment in Australia
Recruitment state(s)
Recruitment hospital [1] 16126 0
St George Hospital - Kogarah
Recruitment hospital [2] 16127 0
St George Private Hospital - Kogarah
Recruitment postcode(s) [1] 29645 0
2217 - Kogarah

Funding & Sponsors
Funding source category [1] 305257 0
Name [1] 305257 0
St George Hospital
Address [1] 305257 0
Gray St, Kogarah NSW 2217
Country [1] 305257 0
Primary sponsor type
Linda Zhang
St George Hospital
Gray St Kogarah NSW 2217
Secondary sponsor category [1] 305618 0
Name [1] 305618 0
Address [1] 305618 0
Country [1] 305618 0

Ethics approval
Ethics application status
Ethics committee name [1] 305599 0
Human Research Ethics Committee Prince of Wales Hospital
Ethics committee address [1] 305599 0
G71 East Wing Edmund Blacket Building
Prince of Wales Hospital
Randwick NSW 2031
Ethics committee country [1] 305599 0
Date submitted for ethics approval [1] 305599 0
Approval date [1] 305599 0
Ethics approval number [1] 305599 0
HREC ref no 18/199

Brief summary
Zenker diverticulum is a herniation of the oesophageal mucosa resulting in pouch formation which can result in dysphagia and spontaneous regurgitation. Treatment with flexible endoscopic myotomy demonstrates lower morbidity compared to previous modalities. However, there is no established standard approach with unknown
optimal technique. While the principal is to cut the cricopharyngeal muscle, a careful balance needs to be achieved to not cause perforation, while noting that an incomplete myotomy leads to higher recurrence rates.
Intra-procedural measurement of distensibility across the Zenker's using the endoscopic Functional Lumen Imaging Probe (FLIP) could allow real-time determination of whether further incision will be required. Through retrospective review of medical records we hope to determine the feasibility of intra-procedural FLIP measurements in these patients, and assess whether there is a correlation between changes of distensibility following myotomy with symptoms and pouch size. We expect approximately 10 patients and hope to show that intra-procedural measurements will help to guide extent of myotomy to minimise risk of perforation as well as recurrence.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 100918 0
Dr Linda Zhang
Address 100918 0
St George Hospital
Gray St Kogarah
NSW 2217
Country 100918 0
Phone 100918 0
Fax 100918 0
Email 100918 0
Contact person for public queries
Name 100919 0
Dr Linda Zhang
Address 100919 0
St George Hospital
Gray St Kogarah NSW 2217
Country 100919 0
Phone 100919 0
+61 0291131111
Fax 100919 0
Email 100919 0
Contact person for scientific queries
Name 100920 0
Dr Linda Zhang
Address 100920 0
St George Hospital
Gray St Kogarah
NSW 2217
Country 100920 0
Phone 100920 0
Fax 100920 0
Email 100920 0

Data sharing statement
Will individual participant data (IPD) for this trial be available (including data dictionaries)?
No/undecided IPD sharing reason/comment
Only grouped data will be shared.
What supporting documents are/will be available?
Ethical approval
How or where can supporting documents be obtained?
Type [1] 7365 0
Ethical approval
Citation [1] 7365 0
Link [1] 7365 0
Email [1] 7365 0
Other [1] 7365 0
Summary results
Have study results been published in a peer-reviewed journal?
Other publications
Have study results been made publicly available in another format?
Results – basic reporting
Results – plain English summary