Comparison of Gastric Alimetry® body surface gastric mapping versus electrogastrography spectral analysis

Abstract

Electrogastrography (EGG) non-invasively evaluates gastric motility but is viewed as lacking clinical utility. Gastric Alimetry® is a new diagnostic test that combines high-resolution body surface gastric mapping (BSGM) with validated symptom profiling, with the goal of overcoming EGG’s limitations. This study directly compared EGG and BSGM to define performance differences in spectral analysis. Comparisons between Gastric Alimetry BSGM and EGG were conducted by protocolized retrospective evaluation of 178 subjects [110 controls; 68 nausea and vomiting (NVS) and/or type 1 diabetes (T1D)]. Comparisons followed standard methodologies for each test (pre-processing, post-processing, analysis), with statistical evaluations for group-level differences, symptom correlations, and patient-level classifications. BSGM showed substantially tighter frequency ranges vs EGG in controls. Both tests detected rhythm instability in NVS, but EGG showed opposite frequency effects in T1D. BSGM showed an 8× increase in the number of significant correlations with symptoms. BSGM accuracy for patient-level classification was 0.78 for patients vs controls and 0.96 as compared to blinded consensus panel; EGG accuracy was 0.54 and 0.43. EGG detected group-level differences in patients, but lacked symptom correlations and showed poor accuracy for patient-level classification, explaining EGG’s limited clinical utility. BSGM demonstrated substantial performance improvements across all domains.

Gastric Alimetry® Test Interpretation in Gastroduodenal Disorders: Review and Recommendations

“…We have established the first phenotype set that is based on proposed mechanisms of gastric activity and symptom generation [30]. This has been further supported by comparisons to other conventional diagnostic tests such as EGG [16] and GET [31], as well as in its potential to guide patient-specific therapy [32].…”

“…Historically, electrogastrography (EGG), was introduced as a clinical tool for assessing gastric myoelectric activity using a small number of cutaneous electrodes [15]. Although it is non-invasive and easy to administer, EGG had multiple limitations that hindered clinical utility and adoption, including poor specificity for normal vs. disease states in individual patients, and a lack of clear impact on clinical care [15,16].…”

The Effects of Heart Rate Variability Biofeedback on Functional Gastrointestinal Disorders: A Scoping Review

“…Due to the lack of physiological biomarkers within FGID, there are new methods being developed, giving researchers and clinicians an insight into the physiology of FGIDs and providing biomarkers for analysis. One such example is Body Surface Gastric Mapping (BSGM), a method that can measure gastric electrical activity with high accuracy and correlation to symptomatology, providing a new understanding of the physiological basis of FGID symptoms (Schamberg et al 2023). This is also a potential tool that can be used to provide an objective measurement and understanding of the symptoms that participants experience in future trials, using a validated app-based approach (Sebaratnam et al 2022).…”