A very low-calorie diet (VLCD) is often used to shrink the liver prior to laparoscopic surgery to facilitate easy access to the hiatus. However, little is known about the optimal timeframe of a VLCD prior to surgery and whether weight loss equates to a reduction in liver volume. We have recently developed a reliable bedside ultrasound method to measure liver volume and acquired funding to compare this technique to magnetic resonance imaging (MRI) before and after a VLCD.
16 patients were recruited who met the study inclusion criteria (over 18 years old, BMI > 25kg/m2, and meets criteria for laparoscopic fundoplication. Patients met with a dietician and a baseline ultrasound, MRI, and body composition analysis was performed. A VLCD was commenced and a weekly ultrasound occurred to determine the change in liver volume. The day prior to surgery, a second MRI, ultrasound, and body composition analysis were performed. Funding was provided by a Royal Adelaide Hospital 2018 clinical project grant
Preliminary results based on the initial 8 patients show that two weeks of a VLCD were sufficient to achieve optimal liver shrinkage if the starting BMI was less than 30. In patients with an initial BMI over 30, at least 3 weeks of a VLCD were necessary. Liver volume loss by ultrasound was a better predictor of fat loss than liver volume loss by MRI.
With a BMI less than 30kg/m2, two weeks of a VLCD is sufficient to achieve maximal liver volume reduction prior to laparoscopic surgery. With a BMI greater than 30kg/m2, at least 3 weeks of a VLCD is necessary. Bedside ultrasound measurements were comparable to MRI measurements and could be used to confirm readiness for surgery.