Migration of pacemaker lead into the spinal venous plexus: case report with special reference to Batson's theory of spinal metastasis

Revisiting the Vertebral Venous Plexus-A Comprehensive Review of the Literature

The venous drainage of the vertebral and paravertebral regions is important for a better understanding of hematogenous disease spread. Moreover, the spine surgeon must be well acquainted with this anatomy to minimize intraoperative and postoperative complications. A comprehensive review of the vertebral venous plexus (Batson plexus) was performed with a concentration on the clinical and surgical correlations of this venous network.

Lumbar tumor resections and management

More than one-third of patients with cancer have vertebral metastases found at autopsy. Primary and metastatic tumors to the spinal column can lead to pain, instability, and neurologic deficit. Symptomatic lesions are most prevalent in the thoracic spine (70%), followed by the lumbar spine (20%) and cervical spine (10%). Lesions in larger vertebral bodies tend to be asymptomatic given the increased ratio between the diameter of the spinal canal and the traversing nerve roots.

Compressive loading at the end plate directly regulates flow and deformation of the basivertebral vein: an analytical study

BACKGROUND

Metastatic diseases and infections frequently involve the spine. This is the result of seeding of the vertebral body by tumor cells or bacteria delivered by venous blood from Batson's plexus, which is hypothesized to enter the vertebral body via the epidural veins. Isolated spinal segments deform significantly at the bony end plate when under compression. This deformation could cause a volume change of the vertebral body and may be accompanied by retrograde flow of venous blood. To date, this process has not been investigated quantitatively. The purpose of this study was to determine the volume changes of the vertebral body and basivertebral vein for a vertebral body under compression.

METHODS

A three-dimensional finite element mesh model of the L4 segment with both adjacent discs was modified from a 3-D computed tomography scan image. An octagon representing the basivertebral vein was introduced into the center of the vertebral body in the model. Four compressive orientations (1500 N) were applied on the top disc. The volume change of the vertebral body model and the basivertebral vein were then computed.

RESULTS

The volume change of the vertebral body was about 0.1 cm3 (16.3% of the basivertebral vein) for the four loading conditions. The maximum cross-sectional area reductions of the basivertebral vein and volume reduction were 1.54% and 1.02%, for uniform compression.

CONCLUSION

Our study quantified the small but significant volume change of a modeled vertebral body and cross-sectional areas and that of the basivertebral vein, due to the inward bulging of the end plate under compression. This volume change could initiate the reverse flow of blood from the epidural venous system and cause seeding of tumors or bacterial cells.

Long-standing intraspinal glass fragments causing subsequent radiculopathy after dorsal stabilization

A 37-year-old female presented with a history of lumbar intraspinal glass fragments due to an accident in childhood. The patient developed progressive right convexity thoracolumbar scoliosis during puberty. Twenty-eight years after the accident, horizontalization of this deformity was performed by dorsal stabilization. Postoperatively the patient complained of acute L-5 radiculopathy. Radiological examination detected multiple glass fragments intra- and extradurally around the L3-4 levels with compression of the dural sac. Microsurgical removal of the extra- and intradural glass fragments led to complete relief of the radicular pain. Foreign bodies can become symptomatic due to changes in the status of the spine, especially during growth in young patients.

Brain metastases: epidemiology and pathophysiology

Metastases are the most common tumors of the central nervous system (CNS), but cancer databases are often incomplete leading to underestimation of the incidence of even symptomatic brain metastases. Brain imaging studies are not routinely performed on neurologically asymptomatic cancer patients and autopsy studies are outdated. Furthermore, while incidence rates for cancers are stable and mortality is decreasing due to earlier detection and better therapy, the incidence of brain metastases appears to be increasing. The pathophysiology of brain metastases is a complex multistage process, mediated by molecular mechanisms; from the primary organ, cancer cells must transform, grow and be transported to the CNS where they can lay dormant for various lengths of time before invading and growing further. Understanding the pathophysiology of brain metastases is of great importance, because it may lead to the development of more efficient therapies to combat brain tumor growth or to possibly make the CNS an undesirable environment for tumor progression.

Evaluation and treatment of spinal metastases: an overview

Metastases to the spine are a common and somber manifestation of systemic neoplasia. The incidence of spinal metastases continues to increase, likely a result of increasing survival times for patients with cancer. Historically, surgery for spinal metastases has consisted of simple decompressive laminectomy. Results obtained in retrospective case series, however, have shown that this treatment provides little benefit to the patient. With the advent of better patient-related selection practices, in conjunction with new surgical techniques and improved postoperative care, the ability of surgical therapy to play an important and beneficial role in the multidisciplinary care of cancer patients with spinal disease has improved significantly. Controversy remains, however, with respect to the relative merits of surgery, radiotherapy, chemotherapy, or a combination of these treatments.

In this topic review, the literature on spinal column and spinal cord metastases is collated to provide a description of the presentation, investigations, indications for surgical therapy, and the role of adjuvant cancer therapies for patients with spinal metastases. In addition, the authors discuss the different surgical strategies available in the armamentarium of the neurosurgeon treating patients with spinal metastasis.