Multichannel magnetogastrogram: a clinical marker for pediatric chronic nausea

Abstract

Chronic nausea is a widespread functional disease in children with numerous comorbidities. High-resolution electrogastrogram (HR-EGG) has shown sufficient sensitivity as a noninvasive clinical marker to objectively detect distinct gastric slow wave properties in children with functional nausea. We hypothesized that the increased precision of magnetogastrogram (MGG) slow wave recordings could provide supplementary information not evident on HR-EGG. We evaluated simultaneous pre- and postprandial MGG and HR-EGG recordings in pediatric patients with chronic nausea and healthy asymptomatic subjects, while also measuring nausea intensity and nausea severity. We found significant reductions in postprandial dominant frequency and normogastric power, and higher levels of postprandial bradygastric power in patients with nausea in both MGG and HR-EGG. MGG also detected significantly lower preprandial normogastric power in patients. A significant difference in the mean preprandial gastric slow wave propagation direction was observed in patients as compared with controls in both MGG (control: 180 ± 61°, patient: 34 ±72°; P < 0.05) and HR-EGG (control: 240 ± 39°, patient: 180 ± 46°; P < 0.05). Patients also showed a significant change in the mean slow wave direction between pre- and postprandial periods in MGG (P < 0.05). No statistical differences were observed in propagation speed between healthy subjects and patients in either MGG or HR-EGG pre/postprandial periods. The use of MGG and/or HR-EGG represents an opportunity to assess noninvasively the effects of chronic nausea on gastric slow wave activity. MGG data may offer the opportunity for further refinement of the more portable and economical HR-EGG in future machine-learning approaches for functional nausea.NEW & NOTEWORTHY Pediatric chronic nausea is a difficult-to-measure subjective complaint that requires objective diagnosis, clinical assessment, and individualized treatment plans. Our study demonstrates that multichannel MGG used in conjunction with custom HR-EGG detects key pathological signatures of functional nausea in children. This quantifiable measure may allow more personalized diagnosis and treatment in addition to minimizing the cost and potential radiation associated with current diagnostic approaches.

Keywords: chronic nausea; gastric slow wave; magnetogastrogram; pediatric.

Graphical abstract

Figure 1.

Experimental setup to measure magnetogastrogram (MGG) using Superconducting Quantum Interference Device (SQUID) magnetometer and high-resolution electrogastrogram (HR-EGG) using cutaneous electrodes in adolescent patients with chronic nausea and healthy controls.

Figure 2.

Reconstructed SOBI-magnetogastrogram (MGG) spatial maps from healthy control subject (A) and pediatric patient with chronic nausea (C) with corresponding power spectra [control (B); pediatric patient with chronic nausea (D)].

Figure 3.

A and B: gastric slow wave dominant frequencies from magnetogastrogram (MGG) and high-resolution electrogastrogram (HR-EGG). Pediatric patients with chronic nausea have an abnormal decrease in postprandial dominant frequency. C and D: percent power distribution determined from MGG and HR-EGG. Between controls (n = 10) and patients (n = 10), preprandial MGG showed significant differences in normogastric PPD, but preprandial HR-EGG PPD showed no significant differences. Postprandial MGG and HR-EGG PPD showed significantly lower normal slow waves and significantly higher bradygastria in patients with nausea compared with normal controls. *Significant difference in patients with nausea compared with control values (P < 0.05).

Figure 4.

Magnetogastrogram (MGG) propagation patterns from healthy control subject shows normal anterograde propagation (A) plus retrograde and anterograde propagation (B and C) from a patient with nausea taken during two different recording times.

Figure 5.

Polar histograms for the mean magnetogastrogram (MGG) gastric slow wave propagation direction from preprandial healthy subjects (n = 10) (A); postprandial healthy subjects (n = 10) (B); preprandial patients with nausea (n = 10) (C); and postprandial patients with nausea (n = 10) (D); polar histograms for the mean high-resolution electrogastrogram (HR-EGG) gastric slow wave propagation direction were shown respectively in E–H.

Figure 6.

Gastric propagation speed determined from magnetogastrogram (MGG) and high-resolution electrogastrogram (HR-EGG) for control subjects (n = 10) and pediatric patients with chronic nausea (n = 10) pre- and postprandial.