Teaching Case

A 37-year-old woman, 10 days after the 6th caesarean section and hysterectomy, presented to the ER complaining of a 2 days continuous left lumbar pain, with distermic sensation and dyspnoea.

A chest X-ray was performed and a consolidation was seen in the LLL (Fig. 1).

Due to the wedge-shaped juxtapleural opacification (Hampton hump) observed in the LLL and the lumbar pain, a DE-CT angiogram of the chest and a venous abdominal phase were carried out.

Fig. 2: axial (a), coronal (b), multiplanar and sagittal (c) reformations of the thoracic CT show intraluminal defects in subsegmental branches of the LLL pulmonary artery that dilate and occlude the vessel, suggestive of acute pulmonary thromboembolism. The iodine maps show perfusion defects in the LLL in concordance with the pulmonary infarction.

Figure 3: CT coronal reformation shows a thrombus along the ovarian veins, whose calibre is reactively increased. Thrombosis of the left ovarian vein extends through the left renal vein to its outlet in the inferior vena cava. The described thrombosis constitutes the emboligenic focus towards a segmental branch of the LLL shown in figure 2.

Ovarian vein thrombosis (OVT) is an uncommon condition in postpartum women [1]. Hypercoagulabilitity caused by hormonal changes, venous stasis and a potential endothelial injury during delivery are the main risk factors for its ocurrence [2]. Furthermore, recent surgery (e.g. hysterectomy, as in our case) increases the risk of thrombosis [3]. OVT occurs more commonly in the right ovarian vein due to its compression by the enlarged uterus [4].

Women with OVT complain of abdominal pain which can mimic acute appendicitis or renal colic. Most of the patients present with fever, tachycardia, nausea, and vomiting.

Although usually ultrasonography with Doppler examination is the first technique performed, contrast-enhanced CT shows more sensitivity and specificity [3]. In this case, CT showed distended bilateral ovarian veins, left renal vein and inferior vena cava due to the presence of thrombus. However, we should be aware of the fact that a similar appearance may be seen in CT if a too early acquisition is done, due to mixing effect between the enhanced and non-enhanced blood, causing the effect of pseudothrombus (although in this case, there would not be vein dilatation). When this effect occurs, a delayed acquisition is recommended. MRI can be used when CT is contraindicated.

OVT complications include sepsis and extension of the thrombus to renal veins and/or the inferior vena cava, which can lead to pulmonary embolism [3]. This one is the most common source of mortality in OVT patients with an incidence reported as high as 13% and a 4% risk of mortality [5]. Therefore, the pulmonary embolism must be always taken into account when a patient with OVT suspicion presents with dyspnoea or respiratory symptoms [6].

Intravenous anticoagulation and antibiotics are the current treatment of choice for OVT [1]. Nevertheless, to date, there is not a specific protocol and, therefore, the treatment guidelines for deep lower extremity vein thrombosis are usually applied [3]. Surgical treatment is not indicated routinely [6]; thrombectomy and ligation of the ovarian vein or inferior vena cava filter [7] are only considered in cases of inefficiency of medical therapy after 5 days [3].