Left iliac vein occlusion: its clinical spectrum

Diagnostic performance of lower extremity Doppler ultrasound in detecting iliocaval obstruction

OBJECTIVE

To retrospectively evaluate the performance of two commonly used Doppler ultrasound parameters, namely, venous flow phasicity and response to Valsalva maneuver, in detecting iliocaval obstruction.

METHODS

All imaging studies of patients seen by interventional radiology for lower extremity venous disease at a single institution from 1996 to 2018 were retrospectively identified. Lower extremity ultrasounds with a concurrent magnetic resonance, computed tomography, or conventional venogram performed within the next 7 days, which served as gold standard, were further identified (n = 192 examinations, including 313 limbs). Iliocaval obstruction were assessed by two ultrasound criteria: (1) nonphasic flow and/or (2) nonresponsive flow to Valsalva in the common femoral vein. The sensitivity, specificity, negative predictive value (NPV) and positive predictive value (PPV) for diagnosing iliocaval obstruction were calculated for each ultrasound criterion, and also for when the two criteria were assessed jointly.

RESULTS

Of the 313 limbs assessed for venous flow phasicity, 133 (42.5%) had an iliocaval obstruction confirmed on subsequent venography. Nonphasic flow demonstrated a sensitivity of 69.2%, specificity of 82.8%, NPV of 78.4%, and PPV of 74.8% for diagnosing iliocaval obstruction. Of the 212 limbs assessed for Valsalva response, 88 (41.5%) had a confirmed iliocaval obstruction. Nonresponsive flow to Valsalva demonstrated a sensitivity of 13.6%, specificity of 97.6%, NPV of 61.6%, and PPV of 80.0% for diagnosing iliocaval obstruction. Joint assessment using phasicity and Valsalva criteria demonstrated a sensitivity of 68.2%, specificity of 87.2%, NPV of 79.6%, and PPV of 78.9%.

CONCLUSIONS

In this tertiary care setting, Doppler ultrasound examination was not a reliable diagnostic tool for detecting iliocaval obstruction.

Surgical Technique of Vertebral Body Removal and Anterior Reconstruction in L5 Spondylectomy

Introduction

L5 spondylectomy for the treatment of spinal tumor is a technically demanding surgery because of the complex anatomy of major vessels, the obscurity of the posterior exposure from the iliac wings, and the increased comparative size of the L5 vertebral body. In this study, we present a surgical technique of L5 spondylectomy, vertebral body removal, and anterior reconstruction for a case with solitary spinal metastatic renal cell carcinoma (RCC).

Technical Note

A 54-year-old man underwent right total nephrectomy for RCC one year ago. At the one-year postoperative follow-up, CT scan and MRI revealed a solitary L5 spinal metastasis. A two-stage posteroanterior approach was performed. To facilitate vertebral body removal, transverse processes were separated from the vertebral body by using the posterior approach. On the basis of the anterior approach, the vertebral body was removed via the interval space between the left common iliac vessels. Reconstruction was performed by using a liquid-nitrogen-frozen, tumor-bearing bone mixed with an autogenous bone graft in an expandable titanium cage.

Results

No intraoperative complications were observed. Postoperatively, the patient exhibited muscle weakness in the tibialis anterior and extensor hallucis longus bilaterally but improved with time. Seven months after the operation, the patient was able to walk independently. At the recent 2.5-year follow-up, the local recurrence of lesions was nonexistent. The bone graft had fused with the adjacent vertebrae.

Conclusion

This report described a novel technique for L5 spondylectomy that can facilitate safe L5 vertebral body removal and demonstrated the effectiveness of liquid-nitrogen-frozen, tumor-bearing bone mixed with autogenous bone graft in anterior reconstruction both in terms of oncologic safety and biological healing.

May-Thurner Syndrome Presenting With Venous Claudication

More than half of patients who present with left-sided iliac vein obstruction have an underlying iliocaval compression syndrome caused by anatomic compression of the left common iliac vein by the overlying right common iliac artery. Because young women are particularly at risk for this condition, commonly referred to as May-Thurner syndrome, suspicion should increase for female patients presenting with iliofemoral obstruction following prolonged bed rest or presenting postpartum. Symptoms are variable, depending on the chronicity of the disease and available collateral circulation, and range from edema to claudication to phlegmasia cerulea dolens from progressive or acute obstruction. The following is a case study of a patient who presented with severe venous claudication caused by postpartum occlusion of her left external iliac vein. Her left common iliac vein was found to be chronically occluded due to iliocaval compression.

Major vascular injury during anterior lumbar spinal surgery: incidence, risk factors, and management

STUDY DESIGN

Retrospective chart review.

OBJECTIVE

To examine the incidence of major vascular injury during anterior lumbar spinal surgery, attempt to identify predisposing risk factors, and to discuss management techniques.

SUMMARY OF BACKGROUND DATA

Major vascular injury can be a catastrophic complication of anterior lumbar spinal surgery.

METHODS

Current procedural terminology codes were used to identify the occurrence of major vascular injury, defined as injury to the iliac vessels, vena cava, and aorta. Once identified, the office record, hospital chart, operative note, and diagnostic test results were reviewed in detail.

RESULTS

Three hundred forty-five operations were performed on 338 patients. Incidence of major vascular complication was 2.9% (10 of 345). There were 9 injuries of the common iliac vein and a single aortic injury. Risk factors identified in patients with major vascular injury were current or previous osteomyelitis or discogenic infection (n = 3), previous anterior spinal surgery (n = 2), spondylolisthesis (n = 2; 1 isthmic Grade II, 1 iatrogenic Grade II), large anterior osteophyte (n = 2), transitional lumbosacral vertebra (n = 1), and anterior migration of interbody device (n = 1). Lateral venorrhaphy by suture (n = 6) and hemoclip application (n = 2) was augmented by topical agents, which constituted the sole method of repair on 1 occasion. Magnetic resonance venography demonstrated iliac vein thrombosis in 1 patient.

CONCLUSION

Current or previous osteomyelitis or discogenic infection, previous anterior spinal surgery, spondylolisthesis, osteophyte formation, transitional lumbosacral vertebra and anterior migration of interbody device point to an increased risk of vascular injury during anterior lumbar spinal surgery. Careful handling of the vascular structures and liberal use of topical hemostatic agents can lead to control of hemorrhage and preservation of vascular patency. Routine postoperative surveillance for proximal deep vein thrombosis, by magnetic resonance venography of the pelvic veins and inferior vena cava, should be performed after venorrhaphy.

Endovascular management of venous thrombotic and occlusive diseases of the lower extremities

Acute complications of deep vein thrombosis (DVT) of the lower extremities include pulmonary embolism and venous ischemia. Delayed complications include a spectrum of debilitating symptoms referred to as postthrombotic syndrome (PST). Anticoagulation therapy is recognized as the mainstay of therapy in acute DVT. However, there are few data to suggest any major beneficial effect on PTS, which is thought to be mediated by valve damage and/or occlusive chronic thrombus and venous scarring. Endovascular catheter-directed thrombolysis techniques with pharmacologic thrombolytic agents, used alone or in combination with mechanical thrombectomy devices, have been proven highly effective in clearing acute DVT, which may allow the preservation of venous valve function and prevention of subsequent venous occlusive disease. Definitive management of underlying anatomic occlusive abnormalities can also be undertaken.