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Trial registered on ANZCTR

Registration number
Ethics application status
Date submitted
Date registered
Date last updated
Type of registration
Prospectively registered

Titles & IDs
Public title
Does having a Minimizer Ring help prevent the stomach stretching and weight regain after a sleeve gastrectomy?
Scientific title
The efficacy of the Minimizer Ring in preventing sleeve dilatation and weight regain (total weight loss) after a primary laparoscopic sleeve gastrectomy, and its effect on complication rate, de novo reflux and food tolerance.
Secondary ID [1] 294703 0
Universal Trial Number (UTN)
Trial acronym
Linked study record

Health condition
Health condition(s) or problem(s) studied:
Obesity 307570 0
Condition category
Condition code
Surgery 306640 306640 0 0
Surgical techniques
Metabolic and Endocrine 306787 306787 0 0
Diet and Nutrition 306788 306788 0 0
Musculoskeletal 306789 306789 0 0

Study type
Description of intervention(s) / exposure
The intervention is the placement of a Minimizer Ring (a silicone ring) at the time of a laparoscopic sleeve gastrectomy (LSG). The ring is placed by a bariatric surgeon with approximately 10 years experience at performing LSGs and approximately 4.5 years experience of placing the Minimizer Ring. The ring is placed around the sleeve (stomach remnant) immediately after the excised stomach is removed during a LSG thus in surgical theatre under a general anaesthesia. Patients will be randomised into two goups - one that recieves the ring and one that does not. The ring is placed loosely around the sleeve at a typical diameter of 8cm. If the ring cannot be fixed loosely, it will not be placed. Currently this is a rare occurrence. The progress of all patients will then be monitored for 3 years after surgery.
Intervention code [1] 301013 0
Treatment: Devices
Comparator / control treatment
The control group will consist of patients who undergo a LSG without the silicone ring placed.
Control group

Primary outcome [1] 305661 0
Total percentage weight loss (kg) measured on a digital scale.
Timepoint [1] 305661 0
6mo, 12mo, 18mo, 24mo, 30mo and 36mo (primary time-point) post-LSG
Secondary outcome [1] 346069 0
Sleeve (stomach volume cm3) as measured by a CT Fizzogram
Timepoint [1] 346069 0
Three years post-LSG
Secondary outcome [2] 346070 0
The presence of reflux as measured by a pH nasopharyngeal probe.
Timepoint [2] 346070 0
Three years post-LSG
Secondary outcome [3] 346071 0
Symptoms of reflux as measured by GSAS (reflux) questionnaire
Timepoint [3] 346071 0
Pre-surgery (when the patient presents to clinic to sign the surgical consent), 6mo, 12mo, 18mo, 24mo, 30mo and 36mo post-LSG.
Secondary outcome [4] 346072 0
Food tolerance score as measured by Suter (food tolerance) questionnaire
Timepoint [4] 346072 0
6mo, 12mo, 18mo, 24mo, 30mo and 36mo post-LSG

Key inclusion criteria
Patients eligible for a primary LSG aged 18-65yrs and who present to the clinic without already having determined if they do or do not wish to have a Minimizer Ring placed.
Minimum age
18 Years
Maximum age
65 Years
Both males and females
Can healthy volunteers participate?
Key exclusion criteria
Patients who cannot attend appointments primarily due to geographical restraints eg. live remotely and do not visit Perth regularly

Study design
Purpose of the study
Allocation to intervention
Randomised controlled trial
Procedure for enrolling a subject and allocating the treatment (allocation concealment procedures)
Central concealed randomisation by computer software and pair-matched for gender and age-quartile.
Methods used to generate the sequence in which subjects will be randomised (sequence generation)
Pair-matched by gender and age quartile (18-30; 30-40; 40-50; 50-65yrs) computer generated.
Masking / blinding
Blinded (masking used)
Who is / are masked / blinded?
The people receiving the treatment/s

Intervention assignment
Other design features
Not Applicable
Type of endpoint(s)
Statistical methods / analysis

Recruitment status
Reason for early stopping/withdrawal
Lack of funding/staff/facilities
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] 10788 0
St John of God Hospital, Murdoch - Murdoch
Recruitment hospital [2] 10789 0
St John of God Hospital, Subiaco - Subiaco
Recruitment postcode(s) [1] 22527 0
6150 - Murdoch
Recruitment postcode(s) [2] 22528 0
6008 - Subiaco

Funding & Sponsors
Funding source category [1] 299688 0
Commercial sector/Industry
Name [1] 299688 0
Obesity Surgery WA
Address [1] 299688 0
Suite 27, Murdoch Medical Centre, 100 Murdoch Dve, Murdoch WA 6150
Country [1] 299688 0
Primary sponsor type
Ass. Prof. Harsha Chandraratna
Obesity Surgery WA, Suite 27 Murdoch Medical Centre, 100 Murdoch Dve Murdoch WA 6150
Secondary sponsor category [1] 298577 0
Name [1] 298577 0
Prof. Eli Gabbay
Address [1] 298577 0
Respiratory West
1/178 Cambridge Street,
Wembley, WA 6014
Country [1] 298577 0
Secondary sponsor category [2] 298664 0
Name [2] 298664 0
Prof. Joe Proietto
Address [2] 298664 0
The University of Melbourne
Parkville, Victoria 3010
Country [2] 298664 0
Other collaborator category [1] 280089 0
Name [1] 280089 0
Angela Houston
Address [1] 280089 0
Obesity Surgery WA, Suite 27 Murdoch Medical Centre, 100 Murdoch Dve, Murdoch WA 6150
Country [1] 280089 0

Ethics approval
Ethics application status
Ethics committee name [1] 300218 0
University Notre Dame Australia Human Research Ethics Committee
Ethics committee address [1] 300218 0
23 High Street, Fremantle, WA 6160
Ethics committee country [1] 300218 0
Date submitted for ethics approval [1] 300218 0
Approval date [1] 300218 0
Ethics approval number [1] 300218 0
Ethics committee name [2] 300234 0
St John of God Health Care Human Research Ethics Committee
Ethics committee address [2] 300234 0
C/o St John of God Subiaco Hospital
12 Salvado Road
Subiaco Western Australia 6008
Ethics committee country [2] 300234 0
Date submitted for ethics approval [2] 300234 0
Approval date [2] 300234 0
Ethics approval number [2] 300234 0

Brief summary
The laparoscopic sleeve gastrectomy (LSG) is currently the most commonly performed bariatric procedure in Australia. Long-term data is beginning to appear in the literature and indicates that up to half of patients who have undergone the surgery regain a significant amount of weight in the years following the surgery. These patients often progress to have further surgery to promote more weight loss. In some patients, the regain in weight is thought to be caused by the stomach stretching in size and the patient can then eat more again. Some surgeons have started placing a silastic ring around the stomach with the original surgery to prevent the stomach from stretching. Long-term data on the efficacy and safety of inserting a ring with a sleeve gastrectomy is scarce. It is also possible that a ring may have an effect on reflux and what foods a person can tolerate.
This study will be a randomised prospective study with the purpose of evaluating the efficacy of a silastic ring in preventing sleeve dilatation (stomach stretching) and deduce any effect on complication rate; reflux; and food tolerance. The study will provide three-year data to assist in determining whether a banded LSG (using a ring) should become the preferred surgical option for the treatment of obesity.
Approximately 95 patients who undergo a banded LSG and 95 patients who receive a standard LSG will be followed for a period of thirty-six months. Patients will be randomised into one of the two study groups. Anthropometric and metabolic data will be collected pre-operative, and at 6, 12, 24 and 36 months after surgery. Food tolerance and reflux evaluated . Stomach capacity will be measured by a Computerised Tomography (CT) Fizzogram at 36 months post-operative. Participants will be asked to have a nasopharyngeal 24 hr pH probe placed at 36 months’ post-operatively irrespective of symptoms as per current clinical practice.
Patients presenting before 36 months with weight regain and /or symptomatic reflux will have a CT Fizzogram or oropharyngeal pH monitoring performed earlier, as per normal clinical practice.
Trial website
Trial related presentations / publications
Public notes

Principal investigator
Name 82950 0
Ms Angela S Houston
Address 82950 0
Obesity Surgery WA, Suite 27 Murdoch Medical Centre, 100 Murdoch Dve, Murdoch WA 6150
Country 82950 0
Phone 82950 0
Fax 82950 0
Email 82950 0
Contact person for public queries
Name 82951 0
Ms Angela S Houston
Address 82951 0
Obesity Surgery WA, Suite 27 Murdoch Medical Centre, 100 Murdoch Dve, Murdoch WA 6150
Country 82951 0
Phone 82951 0
Fax 82951 0
Email 82951 0
Contact person for scientific queries
Name 82952 0
A/Prof Harsha Chandraratna
Address 82952 0
Obesity Surgery WA, Suite 27 Murdoch Medical Centre, 100 Murdoch Dve, Murdoch WA 6150
Country 82952 0
Phone 82952 0
Fax 82952 0
Email 82952 0

No information has been provided regarding IPD availability
Summary results
No Results