Cap-assisted endoscopic sclerotherapy for internal hemorrhoids: technique protocol and study design for a multi-center randomized controlled trial

Abstract

Background: Cap-assisted endoscopic sclerotherapy is a new interventional therapy for internal hemorrhoids and rectal prolapse under colonoscopy. The proper length of the endoscopic injection needle is the core for performing cap-assisted endoscopic sclerotherapy well with more benefits and less complications. However, no data are currently available to guide endoscopists to consider the length of injection needle before cap-assisted endoscopic sclerotherapy. This study is designed to evaluate the efficacy and safety of cap-assisted endoscopic sclerotherapy with long or short injection needle in the treatment of internal hemorrhoids.

Methods: This is a nationwide multi-center, prospective, single-blind and randomized controlled trial. Patients with grade I-II internal hemorrhoids who have failed to conservative treatments and grade III internal hemorrhoids who are not suitable for surgery or refuse surgery will be included. Participants will be randomized 1:1 into either long or short injection needle group. The primary outcome is the recurrence rate of internal hemorrhoids 24 weeks after cap-assisted endoscopic sclerotherapy. The secondary outcomes are as follows: (1) symptom severity score, (2) three-level EuroQoL five dimensions health scale scores, (3) occurrence of adverse events and severe adverse events, and (4) patients' attitudes toward cap-assisted endoscopic sclerotherapy. Data collection will be conducted before and during operation, the 1st day, 1st week, 2nd week, and 24th week after cap-assisted endoscopic sclerotherapy.

Discussion: The outcome of this study is expected to provide a practical clinical protocol of cap-assisted endoscopic sclerotherapy for patients with internal hemorrhoids and promote the use of this new endoscopic technique.

Trial registration: ClinicalTrials.gov, NCT03917056. Registered on 12 April 2019.

Keywords: cap-assisted endoscopic sclerotherapy; endoscopy; hemorrhoids; prolapse; randomized controlled trial; sclerotherapy.

Figure 1.

Flowchart of the trail.

Figure 2.

The procedure and checklist of the trial.

Figure 3.

The difference of (a and b) therapeutic procedure, effect, and (c) length between the long injection needle group and the short injection needle group.

Figure 4.

The operation steps of CAES. (a) A full scale of colonoscopy is recommended prior to CAES. (b) The injection needle is advanced to the targeted points through the endoscopic channel to inject the sclerosing agent. (c)–(e) Then choose the injection sites in clockwise order.