Extra-thoracic Findings on the Venous Phase of Combined Computed Tomographic Venography and Pulmonary Angiography

Non-traumatic thoracic emergencies: CT venography in an integrated diagnostic strategy of acute pulmonary embolism and venous thrombosis

“…The CTV has been performed using sequential [38,39,40,43,51,68], spiral [41,48,56,57,77,78] or mixed technique [54,58]. Results are most often compared to US which is known to be a weak standard of reference (Table 1).…”

“…The clot was not evidenced on the early phase of SCTA, due to strong contrast enhancement and inflow artefacts from the IVC (not shown). The right heart chambers will probably be better studied when using ECG-gated multi-slice CT [40,41,51,54,58,68,80]. In one study the addition of CTV to SCTA increased the accuracy of detection of VTE from 69 to 88% [74].…”

“…Other advantages were more accurate demonstration of extension of DVT, particularly in pelvic and abdominal veins [39,40,51,58,79]. Additional findings and alternative diagnoses for the clinical symptoms were also provided by CTV [39,54,56,68]. Other authors have suggested to perform limited CTV of the pelvis only or pelvis and abdomen, in combination with SCTA, when a previous US was negative.…”

“…Theoretical advantages of the sequential technique is to reduce the number of slices and total irradiation. We perform 5-mm slice every 20 mm (15-mm interslice gap) [39], whereas others use 5-to 10-mm-thick sections every 50 mm (40-to 45-mm interslice gap) [3,38,51,68] or 10 mm every 20 mm (10-mm interslice gap) [40]. We found that a Fig.…”

“…12 Beam-hardening artefact from opacified ureter in a 55-year-old man. Axial CT venogram at the level of the pelvis demonstrates a linear filling defect in the right internal iliac vein (arrow) that corresponds to streak or beam-hardening artefact from contrast in the right ureter located anteriorly 13,14,15) [39,54,56,68]. Computed tomographic venography may also decrease multiple referrals to CT units for suspected malignancy as an underlying cause for VTE [59].…”