The assessment of gastroesophageal reflux (GER) in children: A comparative study with scintigraphy and 24 hr ambulatory pH monitoring

Objectives Among the several diagnostic examinations used in children with GER, scintigraphy appears to be simple and well-tolerated procedure with low raditaion dose. This study aimed to assess the reliability of scintigraphy in children with GER in comparison with 24 hr ambulatory pH monitoring which has been considered as a gold standard by most.

Methods A total of 97 children (age 1 mo- 18 yrs) with GER symptoms underwent Tc-99m SC labelled milk scan (64 matrix, 20-30 sec/frame, 60 min.acquistion) and 24 hr ambulatory pH recording in a short interval. Comparative data of obtained from both methods were available in 89 pts. Scintigraphic findings were evaluated semi-quantitatively and the severity of reflux, the number of reflux episodes and visualization level (proximal, mid, distal the esophagus) were graded. The occurrence of the first reflux event in the initial half of the imaging period (first 30 minutes) or the last 30 minutes (late postprandial) was also recorded. Gastric emptying (GE) rate was measured. On pH recording, the percentage of total time that esophageal pH was < 4 was expressed as a reflux index (RI) and the patient was considered to have GER if the RI was > 4 %.

Results Scintigraphy and pH records indicated total agreement in supporting or excluding the presence of GER in 71 of 89 pts (79.7 %). However, discordant findings were noted in 18 pts. Scintigraphic reflux severity was concordant with increasing RI index in most pts. In all but 2 patients, initial reflux episode occurred in the first 30 min. period of imaging. Residual gastric activity at 60 min. ranged from 15 -90 %, however no clear relationship with GER could be defined.

Conclusions Scintigraphy seems to be a reliable diagnostic test to assess the presence of GER in symptomatic children. However discordant findings might indicate the potential limitations of both methods and the facts related to the reflux content, volume or clearing mechanisms