Spinal Cord Tumor: Dr. Jho's Anterolateral or Posterolateral Approach for Endoscopic Spinal Cord Tumor Surgery

Spinal Cord Tumor: Dr. Jho's Anterolateral or Posterolateral Approach for Endoscopic Spinal Cord Tumor Surgery

Dr. Jho's Minimally Invasive Spinal Cord Tumor Surgery: Anterolateral or Posterolateral Approach for Spinal Cord Tumors, Endoscopic Spinal Cord Tumor Surgery

Hae Dong Jho, M.D.& Ph.D.

Professor & Chair, Department of Neuroendoscopy

Jho Institute for Minimally Invasive Neurosurgery

Dr. Jho has developed various minimally invasive spinal tumor surgeries such as an anterolateral approach, a posterolateral approach, an endoscopic approach, etc. These minimally invasive approaches accomplish adequate tumor removal with maximal protection of the spinal cord and spinal nerves. These approaches often eliminate the need for bone fusion also.

Spinal cord tumors include spinal bone tumors, tumors located in the spinal canal but outside the spinal cord itself (extramedullary tumors), and tumors of the spinal cord itself (intramedullary).

Spinal bone tumors can be divided into cancerous tumors and benign tumors. Cancerous spinal bone tumors include metastatic cancers and primary bone cancers. Although any type of cancers can spread to the spinal bone, the most common ones include lung cancers, breast cancers, prostate cancers, kidney cancers, and lymphomas. Primary cancerous spinal bone tumors are relatively uncommon and include chordomas, osteosarcomas, chondrosarcomas, Ewing's sarcomas, multiple myelomas, lymphomas etc. Treatments for these malignant tumors must involve multimodality measures including surgery, chemotherapy and radiation. Benign spinal bone tumors include osteoid osteomas, osteoblastomas, osteochondromas, giant cell tumors, aneurysmal bone cysts, plasmacytomas, hemangiomas, etc. Treatments for these benign tumors have to be individualized depending on the type of pathology and their symptoms.

Two common extramedullary tumors are neurofibromas and meningiomas. Neurofibromas can occur as a sporadic condition or as a genetic disorder such as neurofibromatosis. These are benign tumors that often require surgical removal.

Although hemangioblastomas, epidermoid, dermoid, and others can rarely occur, the two most common intramedullary tumors are astrocytomas and ependymomas. Treatment involves primarily surgical resection. Radiation treatments may be required in some cases as an adjunctive treatment.

Anterolateral Approach to Spinal Cord Tumors

Figure 1. Schematic drawings, axial (A) and lateral oblique view (B) demonstrate exposure of a spinal cord tumor through a small hole of anterior microforaminotomy (anterolateral approach).

Figure 2. MR scans, axial views, show a spinal cord meningioma (A, an oval gray shadow at the center) preoperatively, and complete removal of the tumor postoperatively (B). Surgical access tract is demonstrated in a white shadow by contrast enhancement.

Figure 3. MR scans, sagittal views, reveal a spinal cord tumor and bony spurs at the C5-6 level preoperatively (A, a white shadow) and total removal of the tumor and bony spurs postoperatively (B). In this technique, bone graft fusion and metal implants are not necessary. Patients are hospitalized only overnight and do not need cervical collars postoperatively.

Figure 4. These intraoperative photographs were taken during an anterolateral approach to a spinal cord tumor. A neurofibroma is exposed through an anterolateral microforaminotomy hole. The upper (A) and lower (B) edge of the tumor are demonstrated.

Posterolateral Approach for Spinal Cord Tumors

Figure 1. Schematic drawings show a patient's positioning, a line of a skin incision (3-5 cm) (A), and a surgical approach (B).

Figure 2. A bony tumor (osteoma) is demonstrated in a postmyelographic CT scan preoperatively (A, arrow), and total removal of the tumor is confirmed in a postoperative CT scan (B).

Figure 3. A preoperative MR scan, sagittal view, reveals a spinal cord tumor (hemangioblastoma) (A, arrow). A postoperative MR scan, sagittal view, confirms total removal of the tumor (B). An intraoperative photograph demonstrates the lateral aspect of the stretched spinal cord and the tumor (C, arrows).

Facts About These Surgeries

These approaches conserve anatomical structure during the removal of spinal cord tumors.

These procedures are innovative because they offer an effective alternative to undergoing more extensive procedures which often require metal spinal implants and bone fusion.

These methods are less invasive than conventional methods because bone resection is minimized.

Shorter hospital stays are involved than in conventional procedures.

Postoperative braces are generally not required.

Discussion

Both of these approaches, the anterolateral approach (which means the surgeon approaches from the front and to the side), and the posterolateral approach (which indicates the surgeon is working from the back and to the side), are bone-sparing procedures which focus on maintaining the structural stability of the spine. Conventional procedures often require extensive bone removal from the spine which then necessitates fusion and/or placement of metal implants to provide stability. The anterolateral approach spares bone by using small anterior foraminotomy holes (made for tumor access) and allows preservation of the structural integrity of the bone. The posterolateral approach spares bone by utilizing a limited hemilaminectomy. Most patients are able to be discharged the day following surgery. Various minimally invasive endoscopic techniques have been also used for different types of spinal cord tumors.

Definitions

foraminotomy - enlargement of an opening or passageway for a nerve root.

hemilaminectomy - excision of a vertebral lamina on one side.

References

Jho HD: Posterolateral approach for anteriorly located cervical spinal cord tumors. Minimally Invasive Neurosurgery 41:204-208, 1998

Jho, HD and Ha, HG: Anterolateral approach for cervical spinal cord tumors. Minimally Invasive Neurosurgery 42:1-6, 1999