Gastric Electrical Stimulation for the Treatment of Obesity: From Entrainment to Bezoars—A Functional Review

Abstract

Growing worldwide obesity epidemic has prompted the development of two main treatment streams: (a) conservative approaches and (b) invasive techniques. However, only invasive surgical methods have delivered significant and sustainable benefits. Therefore, contemporary research exploration has focused on the development of minimally invasive gastric manipulation methods featuring a safe but reliable and long-term sustainable weight loss effect similar to the one delivered by bariatric surgeries. This antiobesity approach is based on placing external devices in the stomach ranging from electrodes for gastric electrical stimulation to temporary intraluminal bezoars for gastric volume displacement for a predetermined amount of time. The present paper examines the evolution of these techniques from invasively implantable units to completely noninvasive patient-controllable implements, from a functional, rather than from the traditional, parametric point of view. Comparative discussion over the available pilot and clinical studies related to gastric electrical stimulation outlines the promises and the fallacies of this concept as a reliable alternative anti-obesity strategy.

Updates on gastric electrical stimulation to treat obesity: Systematic review and future perspectives

“…Generators were implanted in a subcutaneous pouch on the anterior abdominal wall. The mucosa has a higher impedance than the serosa, limiting the spread of electrical stimuli into muscular and neural networks in the stomach [22] . However, the correct placement through the different layers was checked by means of perioperative endoscopy, which can be less accurate than electrophysiology or image-guided testing (such as high frequency endoscopic ultrasound).…”

“…Intestinal electrical stimulation (IES) is used in the duodenum or the colon. It affects intestinal slow waves, contractions and transit through vagal and cholinergic and adrenergic pathways [22] . Just like GES, there are various types of pulses for IES such as long pulse, short pulse, train of short pulses, dual pulses and synchronized pulse stimulation.…”

“…This seems to be related to various reasons, including lack of insurance coverage in some countries, as well as psychological factors related to the permanent anatomical changes and potential postoperative complications [20,21] . Less invasive anti-obesity therapies, which are increasingly used, include intragastric balloons (space-occupying devices) and bezoars, which are collections that accumulate, coalesce and are retained in the gastrointestinal tract [22] . These devices are not very well tolerated and long-term results are disappointing.…”

“…The most widely known commercial ones are the following [22] : ( The first human use of GES was for the treatment of gastroparesis in Tennessee in 1992, and its use for obesity soon followed in Italy in 1995 [56] . While the GES device for the treatment of nausea and vomiting in patients with gastroparesis, called Enterra ® , is FDA-approved, none of the GES devices have obtained FDA approval to treat obesity…”

A Magnetic Soft Endoscopic Capsule-Inflated Intragastric Balloon for Weight Management

“…Lighter weight of air-filled balloon has been proven by its effectiveness over the fluid-filled balloon due to its safer and longer occupation in the stomach26. Here we present a novel approach for the use of IGB in term of a magnetic soft capsule endoscope (MSCE) with the use of air-filled IGB to reduce the postoperative discomfort like epigastric pain, serve vomiting, and heaviness.…”