Magnetic continent colostomy device.

For patients, the principal drawback of a colostomy is the loss of faecal continence. To achieve a continent colostomy has long been the goal of surgeons. A magnetic stoma seal became feasible when a strong, light, durable magnet made of samarium-cobalt became commercially available in 1972. This metal compound has the highest magnetic energy per unit volume and loses only a few per cent of its power in 100 years. A magnetic ring coated with Palacos (an acrylate used successfully for many years in orthopaedic surgery) was developed in Erlangen, Germany, and has been used there in clinical trials since 1974. The ring is implanted in the anterior abdominal wall, either at the time of abdominoperineal resection (primary) or to make an already established colostomy continent (secondary). The colon is brought through the centre of the ring and a muco-cutoneous suture performed. After healing the patient may wear a matching outside cover, containing a ring-shaped magnet and a protruding magnet on its central core. The cap is so designed to achieve a nearly constant force of attraction over a distance of 10 to 30 mm. The development and manufacture of the device have now been taken over by Coloplast International and is being marketed under the name of Maclet. Before making the product commercially available the manufacturers invited several surgeons in Britain and Scandinavia to try the device and keep accurate details of operative technique, complications, and results. The results were verified and the patients interviewed and examined by a nurse/stomatherapist, who visited the 12 or more centres engaged in the trial. At a recent symposium in London, organised to correlate the preliminary results of the trial and to compare them with the experience from Erlangen, the participants decided that the preliminary results should be published in Britain. Surgical technique The stoma site is carefully chosen before operation on a flat part of the abdominal wall away from ridges and creases; often slightly higher than the usual position. The acrylic-covered magnetic ring is sterilised with gas and inserted either through the hole where the skin disc has been excised (25 to 35 mm diameter) or into the subcuta-neous fat laterally from the main incision or from within the abdomen. The south pole of the magnetic ring is marked with a rim that must be sited towards the skin. The ring is then fixed in the deeper part of the subcutaneous …