The DIAMOND (TANTALUS) system implantation is performed in a minimally-invasive procedure under general anesthesia. The IPG and charger coil are generally implanted in subcutaneous pockets in the abdomen. One bi-polar gastric lead is placed in the fundus for recording of fundus distension, and two bi-polar leads are placed in the pyloric antrum for slow-wave detection and signal delivery.
Two electrodes (bifurcating from a common lead) are placed in the fundus. The proximal electrode is implanted close to the GE junction. The second electrode placed in the fundus is inserted in parallel to the first one, at a similar distance.
Four electrodes are implanted in the pyloric antrum. Two are attached to the posterior part of the antrum and two in the anterior part. The electrodes are attached to the gastric wall.
The electrical signal and antral function can be monitored and modified, if needed, by the external programmer, which is placed over the pulse generator and displays the characteristics of the electrical signaling and the gastric responses when the patient is given a test meal during follow-up visits.
Post implantation, the patient receives standard post-operative care for a minimum of 24 hours prior to discharge.
The DIAMOND (TANTALUS) system is well tolerated in Type 2 Diabetes and obese patients. Most adverse events were non-severe, and unrelated to the procedure or the device. Procedure related adverse events were consistent with similar laparoscopic procedures. Adverse event rate rapidly drops one month post implantation.