P1.052. Photodynamic Therapy (PDT) in the Treatment of Gastroesophageal Reflux Disease (GERD) Complicated by Metaplasia of the Esophageal Mucosa in Children

Topic Benign Disease: Pediatric Esophageal Disorders Background GERD is common among children. Conservative treatment methods and surgical interventions for GERD complicated by esophageal mucosal metaplasia, do not always lead to reversal of the metaplasia or a reduction in the risk of esophageal adenocarcinoma. In some cases, PDT is used after antireflux surgery to target the metaplastic mucosa. Methods Five patients with a diagnosis of esophageal mucosal metaplasia were treated in the Thoracic Surgery Department. Two patients were diagnosed with intestinal esophageal metaplasia and three had cardiac gastric metaplasia. Three patients were female and two were male. The average age of the patients was 15.2 years. All children underwent Nissen fundoplication to correct a hiatal hernia. Due to the development of stenosis of the distal third of the esophagus, the patients underwent multiple sessions of balloon dilation, which produced a temporary positive effect. Given persistent restenosis of the esophageal lumen and the presence of metaplastic areas in the lower third of the esophagus, we used photodynamic therapy (PDT). Five hours before PDT, a chlorine photosensitizer (PS) was administered intravenously for 30 minutes. To perform PDT, a laser system, an optical power meter, a video gastroscope, and a spectrum analyzer were used. Results To achieve complete destruction of metaplastic areas and recanalization of the esophageal lumen, two patients with intestinal metaplasia required 3 sessions of PDT, while 3 patients with cardiac gastric metaplasia required 4 sessions. One patient experienced an esophageal wall burn due to close contact between the light guide and the esophageal wall, which subsequently led to restenosis. A "potentiation" method was developed for children with gastric metaplasia. This method was used during the first PDT session to induce inflammation in the esophageal mucosa and subsequent accumulation of photosynthesis supplements in the metaplastic area. During PDT, the amount of photosynthesis supplements in the tissues was also monitored using spectral analyzer images. Follow-up examinations demonstrated healing of the metaplastic area, followed by epithelial regeneration, as confirmed by histology, and maintenance of a normal esophageal lumen. Conclusion Thus, photodynamic therapy can be effectively used for both intestinal and gastric esophageal mucosal metaplasia in children and adolescents. The efficacy of this method has been demonstrated in a three-year follow-up study. Given the minimally invasive nature of the technique, the comparatively low cost of photosensitizers, laser equipment, and the recording of photosensitizer concentrations in tissues, this provides a basis for further research into the treatment of this condition in children.