A new explanation for an old finding: the ductus bump

Abstract

Received: 1 May 2004 Revised: 25 May 2004 Accepted: 3 June 2004 Published online: 31 July 2004 Springer-Verlag 2004 In this issue of Pediatric Radiology, Kaushik et al. [1] present an asymptomatic neonate with a 7.5-mm-diameter mediastinal mass. The mass was thought to be a ‘‘ductus bump’’ on the initial film and seemed to disappear within 3 days; over time there was calcification in the region of the ligamentum arteriosum [2]. However, what is most interesting about this child is that both CT and ultrasound showed this ‘‘ductus bump’’ to be a clot containing a ductus arteriosus aneurysm (DAA), which indeed did resolve, but not within 3 days. This case report is important because it prompts us to reconsider the various warnings in the literature concerning a DAA. Many authors have discussed the dangers of these aneurysms and in the past most were surgically removed [3–10]. Newer findings and larger studies using echocardiography show us that a DAA is relatively common (1–8.8%) in normal neonates [11]. All of the DAAs which were less than 11.2 mm in diameter disappeared although 30% closed after thrombus formation [11]. The warnings of spontaneous dissecting DAAs, Marfan’s syndrome or aneurysm of the ductal region in adults are probably an entirely different subgroup. Extensive follow-up, invasive imaging or surgery in most neonates is not advisable [12]. Follow-up ultrasound during the first 1– 2 months is the conservative approach. Those DAAs still present after 1–2 months may need treatment. Patients with larger DAAs, or those with family history of connective tissue disorder, may represent a high-risk segment in which more frequent follow-up is important. In the description of calcification of the ligamentum arteriosum by Currarino and Jackson [13], they suggested that calcification was present when the ductus arteriosus was closed. These new echocardiographic data support their 1970 hypothesis but it may be that the DAA has closed. Kaushik’s [1] report ties the ‘‘ductus bump,’’ DAA and calcification of the ligamentum arteriosum together. The concept of the ‘‘ductus bump’’ may not be viable—all of these are most probably DAAs. The approach of noninvasive observation seems quite appropriate.