RESUMO
BACKGROUND: Corrosive esophageal injury due to accidental ingestion is a serious clinical problem in children particularly in developing countries. The present study was conducted to evaluate the diagnostic utility of technetium-99m-pyrophosphate ((99m)Tc-PYP) scintigraphy in the early stage of esophageal burns by using different concentrations of sodium hydroxide (NaOH) in an experimental rat model. MATERIALS AND METHODS: Twenty-eight male Sprague-Dawley rats, weighing 200-250 g, were used in the study. Esophageal burn model was created in 21 rats by gastrically infusion of various concentrations of NaOH. The rats were divided randomly into three groups: mild-burn group (n = 7) received 15% NaOH, moderate-burn group (n = 7) received 30% NaOH and severe-burn group (n = 7) received 45% NaOH. Seven rats were identified as control group and received normal saline. Three hours after burn injury, 1-mCi (99m)Tc-PYP was administered through tail vein. Two hours after (99m)Tc-PYP administration, static imaging with gamma camera was performed. Then, histopathologic assessment of esophageal samples was achieved properly. RESULTS: All NaOH-applied groups (mild, moderate, and severe) showed a significant higher uptake ratio when compared to control group (P < 0.005). NaOH-applied groups displayed important histologic alterations such as mucosal disintegration, edema, inflammation, and stromal damage when compared to control group. Pearson correlation analysis revealed a significant correlation between the (99m)Tc-PYP uptake ratio and histologic score (P < 0.0005). CONCLUSIONS: The scintigraphic imaging may provide advantages in the early stage of esophageal burns in some patients whom endoscopic procedure is contraindicated because of its high risk of complications such as bleeding and perforation.