Diagnosis of a Fetal Neck Mass by Amniography

Abstract

Abnormalities of fetal attitude and presentation may have no apparent etiology or may be caused by a number of fetal, placental, or maternal abnormalities. Menees et al. (6) in 1930 demonstrated the use of amniography in localizing the placenta and cord, in determining fetal sex, and in demonstrating contrast medium in the gastrointestinal tract (indicative of fetal swallowing). Savignac (8) suggested its use in diagnosing uterine or fetal abnormalities in abnormal fetal presentation or in cases of hydramnios. Case Report The patient, a 24-year-old white gravida II, Para 1, was noted at twenty-two weeks gestation to have a uterus measuring approximately 28 cm. An abdominal film obtained at twenty-four weeks gestation demonstrated a single fetus in a breech position with the head markedly deflexed in a greatly enlarged uterine cavity. Because of the diagnosis of polyhydramnios, the patient was treated with bedrest, diuretics, and sodium restriction. The uterine enlargement progressed, however, and at twenty-six weeks the patient was admitted to the hospital. The fundus at this time measured 37 cm. Initial radiographs showed no change in fetal position or attitude, but some fetal growth. Fetal heart tones could not be heard, using the conventional fetoscope. Amniocentesis was performed with the removal of 500 cc of yellow-stained amniotic fluid. Fifty cubic centimeters of 50 per cent Hypaque was then instilled into the amniotic sac. Radiographs obtained after administration of contrast material showed a mass with a diameter of 19 cm involving the anterior neck (Fig. 1). The mass was the cause of the marked deflexion noted on the first abdominal film. The mandible was not seen on the contrast examination, nor had it been seen on the plain films. The scalp was seen to be markedly thickened. Delayed films showed no contrast medium in the intestines. The patient went into labor the following day. Fetal heart tones were heard, using sound amplification, but were of poor quality. A primary cesarean section was performed because of the probable dystocia that would result from a breech presentation with a mass of this size involving the after-coming head. A stillborn male was delivered with a huge mass in the neck markedly deforming the lower face. Postmortem radiographs revealed calcifications within the mass and marked edema of the scalp (Fig. 2). At autopsy, the mass was found to arise from the base of the tongue, compressing the mouth, pharynx, and vessels of the neck, thereby accounting for the scalp edema. The pathologic diagnosis was malignant teratoma. Discussion Localized deflexion of the cervical spine can be caused by a contracted maternal pelvis, placenta praevia, hydramnios, cord around the neck, anomalies of the spine, hypertonus of the posterior neck muscles, as well as neck tumors such as cystic hygroma or thyroid tumors (1, 3, 5).