CASE 8028 Published on 31.01.2010

Low Pack Pain As The Initial Symptom Of IVC Agenesis

Section

Cardiovascular

Case Type

Clinical Cases

Authors

Galanis S, Geroukis T, Bisba K, Kalpakidis V, Palladas P.

Patient

37 years, male

Clinical History
A 37 year old male with a long history of low back pain worsening during lifting was referred to our institution for evaluation of his symptoms.
Imaging Findings
A lumbar spinal MR imaging examination was performed as part of the diagnostic evaluation of his symptoms. MR imaging scans showed tubular structures located at the anterior epidural space along the lumbar segments of the spinal column, with mixed signal intensities on both T1- and T2-weighted series, which happened to compress the thecal sac and were in communication with para-vertebral tubulonudular structures through the neural foraminae on both sides having similar MR-signal intensity. There was also noted a large inhomogeneous "mass" anterior to the L5 vertebral body with similar signal on both T1- and T2-weighted series in communication with the common iliac veins which had no signal void as expected. Above the level of L5 the IVC could not be defined as a separate structure (Fig 1,2). These findings were suggestive of the vascular nature of the lesions. Post contrast T1 Fat Sat axial and sagittal weighted images revealed that the lesions were in fact enlarged paraspinal and epidural venous collaterals and the "mass" was a thrombosed aneurysm at the blind-ended conjunction of the also thrombosed common iliac veins (no signal void) (Fig 3,4). Fig.5 demonstrates the aneurysm and the absence of the infrarenal segment of IVC. We also see that the hepatic segment of the IVC is tiny, hypoplastic and blind-ended. The patient was diagnosed with IVC agenesis and deep venous thrombosis. Figure 6 shows the blood drainage through the azygos-hemiazygos veins and the scalloping of the L3 vertebral body. CT Phlebography with injection of contrast through the dorsal pedal vein (Fig 7).
Discussion
Vascular malformations in the diagnostic spectrum of low back pain are rare. Vascular compression may either be arterial or venous in origin, and venous mass effect is extremely rare regarding the whole spine.
Patients with IVC agenesis may present with symptoms of lower extremity venous insufficiency or idiopathic deep venous thrombosis. If the deep venous collateral system is sufficiently developed and drains the venous blood from the lower extremities to the heart, venous stasis secondary to inadequate blood return through collaterals (resulting in subsequent deep venous thrombosis) is likely to be prevented. The patient presented here had a very large collateral pool draining the lower body venous blood, which reflects the compensated long duration of the process but caused a mass effect secondary to the very large amount of blood overloading the vertebral-paravertebral venous plexus. This mass effect was typically worsening during an activity increasing the intrathoracic pressure (such as lifting), resulting in the decrease of venous return and aggravating the mass effect of the vertebral venous collaterals. The presence of an epidural or paraspinous mass continuous within multiple spinal segments, particularly showing signal void on MR images, should raise the suspicion of a vascular anomaly. Cross-sectional imaging methods facilitate the recognition of these anomalies and avoid a misdiagnosis of a true solid lesion. Overloaded and enlarged venous structures have the potential to compress the nervous system (either the spinal nerves and spinal cord or thecal sac), eventually causing neurologic symptoms, which might be the only and initial symptom; however, venous insufficiency resulting in deep venous thrombosis is a more frequently expected consequence of IVC agenesis.
Differential Diagnosis List
Absent Infra-Renal IVC With Iliac Vein Thrombosis Causing Low Pack Pain
Final Diagnosis
Absent Infra-Renal IVC With Iliac Vein Thrombosis Causing Low Pack Pain
Case information
URL: https://www.eurorad.org/case/8028
DOI: 10.1594/EURORAD/CASE.8028
ISSN: 1563-4086

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