Kamler JP, Lemperle G, Lemperle S, Lehman GA. Endoscopic lower esophageal sphincter bulking for the treatment of GERD: safety evaluation of injectable polymethylmethacrylate microspheres in miniature swine.
Gastrointest Endosc 2010;
72:337-42. [PMID:
20541193 DOI:
10.1016/j.gie.2010.02.035]
[Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/09/2009] [Accepted: 02/14/2010] [Indexed: 12/10/2022]
Abstract
BACKGROUND
Endoscopic therapy for GERD is an appealing, minimally invasive alternative to medical treatment and surgery. Various materials have been tested to augment the lower esophageal sphincter (LES), with limited success. To our knowledge, safety and migration of polymethylmethacrylate (PMMA) microspheres has never been evaluated.
OBJECTIVE
To assess the safety, migration, inflammatory reaction, and durability of PMMA injected into the LES of miniature swine to create a reflux barrier.
DESIGN
Animal study.
SETTING
Approved animal research facilities.
INTERVENTION
Injection of the LES of miniature swine with PMMA. Histopathology of the injected site at certain intervals and postnecropsy microsphere counts of various organs.
MAIN OUTCOME MEASUREMENTS
Minimal inflammatory reaction at the injection site, persistent bulking effect of the material, and no migration of microspheres.
RESULTS
Injection of LES with PMMA caused a mild inflammatory reaction. The bulking effect of the injected material was persistent. Migration of microspheres was eliminated with the use of larger-sized microspheres.
LIMITATIONS
Animal model.
CONCLUSION
Our phase I study documented that 40-microm polymethylmethacrylate microspheres are biocompatible and that PMMA microspheres are resistant to degradation when injected submucosally into the wall of the esophagus. The detection of 40-microm PMMA microspheres in local lymph nodes, liver, and lungs of some animals in the phase I study clearly documented transport of PMMA away from the injection site. This finding was eliminated by increasing the size of microspheres to 125 microm. The potential therapeutic effects of these larger microspheres for humans with GERD remains to be evaluated.
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