A neonate who showed right-sided diaphragmatic elevation on a chest X-ray is presented. Transabdominal plication of the right hemidiaphragm was carried out at 13 days of age. Dur-ing the operation both hemidiaphragms were found to be hypoplastic. The patient died at 15 days of age due to respiratory insufficiency. Diaphragmatic eventration refers to absence or deficiency of diaphragmatic muscle, with resultant elevation. Bilateral diaphragmatic eventration is rare, and its prognosis is extremely poor. The literatures including 20 cases of bilateral diaphragmatic eventration in Japan and the Western Countries were reviewed. The diagnosis by chest X-ray films is rather difficult and complicated. Of these 20 cases, 8 actually showed bilateral elevation. But 6 cases were reported to have unilateral diaphragmatic elevation on the chest X-rays, as presented in our case. Recognition of the existence of the "masked" bilateral diaphragmatic hypoplasia is one of the important factors in managing postoperative respiratory care. Therefore, transabdominal plication of the diaphragm is preferable as the operative procedure, because it is much easier to find bilateral diaphragmatic hypoplasia than thoracic approach.
