Pelvic Congestion Syndrome Initially Detected by Contrast-Enhanced F-18 FDG-PET/CT

Abstract

Pelvic congestion syndrome (PCS) is said to occur as a result of retrograde flow in an incompetent ovarian vein. Ovarian vein incompetence is seen in approximately 10 % of women, and up to 60 % with this abnormality can develop PCS [1]. The etiology of PCS is poorly understood and is likely to be multifactorial. Absence of ovarian vein valves is an important factor in its development [2]. The causes of ovarian varicoceles are multifactorial, involving both mechanical and hormonal factors. Dilatation of the ovarian veins can result in vascular incompetence and retrograde blood flow [3].On either CT or magnetic resonance (MR) imaging studies, pelvic varices in PCS appear as dilated, tortuous, enhancing tubular structures near the ovaries and uterus [4]. In addition, the extension of varices to the broad ligament and paravaginal venous plexus can be appreciated [5]. With CT, the tubular nature of these structures and the pattern of enhancement after intravenous contrast medium administration distinguish them from lymphadenopathy or adnexal masses [6]. Unlike such masses, pelvic varices appear isodense with other veins after contrast enhancement [7].Contrast-enhanced CT data as part of the combined PET/ CT examination provide additional information when compared with non-enhanced PET/CT. Because CT data supply the anatomic background for PET, the most important benefit relates to more precise anatomic localization of pathology by differentiation of the lesion from its surrounding structures [8]. By supporting lesion detection and characterization, CT contrast agents can be of additional value in F-18 FDG non-avid disease [9]. As in the presented case, careful review of CT images in contrastenhanced PET/CT enables the detection of F-18 FDG nonavid disease such as PCS (Fig. 1). As contrast-enhanced F-18 FDG PET/CT had been performed frequently, being familiar with the findings of PCS on the contrast-enhanced CT images would have been helpful for the nuclear medicine physicians.