Gastric volumetry for the assessment of fundic compliance and visceral hypersensitivity in patients with gastroparesis: a retrospective comparative study.

Background/aims: The evaluation of visceral hypersensitivity and gastric accommodation in patients with gastroparesis (GP) is difficult. CT-scan gastric volumetry allows to test the distension of different regions of the stomach. We aimed to study gastric volumes and patient's sensitivity to gastric distension between in patients with GP compared to patients with GERD.
Method: Retrospective study including patients who had CT-scan volumetry for GP or GERD. Two CT-scan series were made after gastric distension: left lateral decubitus 30° (LLD30) for antrum and right lateral decubitus (RLD) for body. Pain and discomfort were assessed using visual analogue scale (VAS). Gastric volumes were measured for LLD30 and RLD.
Results: 13 patients (7 GP and 6 GERD) were included. Mean age was 35.6+/-7.3 years. Median gastric volume in the RLD was lower in GP vs GERD (927+/-208 ml vs. 1115+/-163 ml; p  = 0.046) while it was similar for LLD30 (1053+/-228 ml vs. 1054+/-193 ml; p  = 0.603). GP patients had significantly more pain and discomfort during the procedure: pain VAS for GP was 6[0-9] versus 0[0-2] for GERD, p  = 0.004, discomfort VAS for GP was 7[4-10] versus 4[0-5] for GERD, p  = 0.007. 66.7% of GERD patients felt no pain vs. 14.3% in GP, p  = 0.053.
Conclusion: This pilot study suggests that GP could be associated with a reduced gastric volume compared to GERD in RLD after gaseous distension. In contrast, patient self-assessment of pain related to gastric distension was greater int GP patients. A lack of fundus accommodation and visceral hypersensitivity could explain some mechanisms in the genesis of GP symptoms.