In 1958, the author reported a case of persistent right jugular lymph sac that simulated a cervical tumor (1). This anomaly was visualized by angiocardiography. Recently, a left-sided persistent jugular sac was encountered in a woman, and the purpose of this paper is to record its roentgen demonstration. Case Report A swelling in the left cervical region (Fig. 1,A) was noted in a 56-year-old woman with recurrent attacks of migraine head aches. Characteristically, this enlarged during the Valsalva maneuver, reaching a size of 3 by 2 cm. (Fig. 1,B). No pulsation or bruit was detected in it, but the lesion was soft, fluctuant, and cystic on palpation. Angiocardiography, via the left arm with the patient in the supine position after a mild inspiration, showed a 3 mm. tract extending into a sacciform structure arising from the left subclavian vein adjacent to the left jugular vein (Fig. 2,A). Soon after, a rounded opacified sac was visualized (Fig. 2,B). Later in the series, and also when the Valsalva maneuver...