PREOPERATIVE DIAGNOSES:
1.
Recurrent holocord spinal cord astrocytoma extending from C-5 through T12.
2.
Proximal syringobulbia secondary to spinal cord tumor.
3.
Distal syringohydromyelia secondary to intramedullary spinal cord tumor.
4.
Status post prior laminectomy of C-7 through T-12.
POSTOPERATIVE DIAGNOSES:
1.
Recurrent holocord spinal cord astrocytoma extending from C-5 through T12.
2.
Proximal syringobulbia secondary to spinal cord tumor.
3.
Distal syringohydromyelia secondary to intramedullary spinal cord tumor.
4.
Status post prior laminectomy of C-7 through T-12.
PROCEDURE:
1.
Laminectomy C-5 through T-12 with subsequent replacement and
laminoplasty, C-5 through T-12.
2.
Intradural microdissection and aggressive resection of intramedullary
spinal cord tumor, C-5 through T-12, with drainage of a proximal
syringohydrobulbia and distal syringohydromyelia.
3.
Use of the operating microscope and microdissection.
4.
Intraoperative somatosensory evoked potentials and motor evoked
potentials (Dr. Jaime Lopez).
ESTIMATED BLOOD LOSS:
BLOOD TRANSFUSIONS:
hematocrit.
ANESTHESIA:
Blood transfusions given due to preexisting low
General endotracheal.
PRIMARY SURGEON:
CO-SURGEON:
Approximately 100 to 150 cc.
Michael Edwards, M.D.
Stephen L. Huhn, M.D.
ASSISTANTS: Stephen Ryu, M.D.
Jennifer Zou, M.D., Ph.D.
PROCEDURE IN DETAIL: Xxxxx was brought to the operating room where careful
endotracheal anesthesia was established. Appropriate lines and monitors were
placed. Appropriate recording electrodes and stimulating electrodes were
similarly placed. Arterial line and Foley catheter were placed. The child
was started on the methylprednisolone spinal cord injury protocol. Antibiotic
prophylaxis was given with a third-generation cephalosporin.
Xxxxx was carefully turned prone onto the laminectomy rolls. The face was
carefully placed in the padded gel Mayfield pediatric headrest, and throughout
the procedure, the face was moved and elevated to try to minimize pressure.
We subsequently draped out the entire spine, extending from the occiput to the
mid-lumbar area with Steri-drapes. The skin was scrubbed for 10 minutes with
Betadine soap, painted with alcohol and DuraPrep. The prior incision
extending from L1-2 to C-7 was marked and extended superiorly up into the high
cervical area. A lateral radiograph was obtained, indicating that we were
high enough to obtain removal of bone to C-5.
The skin had been infiltrated with 10 cc of 0.25% local with 1:400,000 of
adrenaline. The skin was opened with a #15-blade and a needlepoint Bovie
scalpel, dissecting the muscle off of the spinous process and lamina,
extending from just above C-5, possibly C-3 and C-4, all the way through L1-2.
Meticulous hemostasis was established with the bipolar cautery.
Attention was first turned to the upper cervical spine area, where we knew
there was significant hydrobulbia. In this area, we carefully drilled away a
small part of the lamina above C-5 to expose dura, and at the junction of
approximately T-1 to T-2, which was the site of our prior surgery. In fact,
it was noted that the laminoplasty had completely healed back into position,
as if there had never been a surgical procedure. The only remnant was the
sutures in the lamina used to replace the entire dorsal portion of the spine.
After exposing the dura proximally and distally, we used the B5 bit on the
Midas Rex drill to perform a laminotomy, extending from approximately T1-2 to
C-5. The lamina and spinous process were preserved. Meticulous hemostasis
was established in the epidural space with bone wax, FloSeal, and Cottonoid
patties.
When we obtained hemostasis, we carefully covered the remaining portion of the
spine. The operating microscope was brought into the field.
Prior to our surgery, somatosensory evoked potentials could not be obtained
from the lower extremities, nor could motor-evoked potentials. Somatosensory
and motor evoked potentials could be obtained from the left upper extremity,
but none from the right upper extremity.
The dura was elevated with a sharp and opened in the midline with a #15 blade,
exposing a markedly swollen, abnormally shaped somewhat vascular cervical
spinal cord. The dura was retracted with fine silk sutures. After the dural
packing sutures were placed, we brought the microscope into the field. Under
high magnification, we carefully coagulated the midline of the cervical spine.
We could not determine where the dorsal columns resided. Using a #11 blade,
we opened the pial surface, which was markedly abnormal, and immediately
entered into tumor at the cervical thoracic region. The tumor was somewhat
gelatinous in areas, and as we extended our midline myelotomy superiorly, we
entered into the cervical portion of the hydrobulbia. This gave us the
proximal portion of the tumor, which extended up as a nodule into the
hydrobulbia. Using the Cavitron, we were able to start debulking the tumor.
We then used fine #7-0 Prolene sutures as pial retraction sutures on the pia
of the cord to hold the cord open. We resected as much of the tumor as we
could, until we reached an interface where we could not tell tumor from normal
cord. This was tedious, prolonged, and throughout the procedure, multiple
evoked potential epics were performed. Throughout the procedure, warm
Physiosol was used to maintain as much physiologic normality of the cord as
possible.
It was clear the tumor extended inferiorly. Therefore, after removing the
tumor from approximately T-1 through C-5, and draining the hydromyelia, we
covered this area with moist pieces of cotton and Telfa. We similarly
identified the dura at the T-1 lamina and extended down to the T-12, L-1 area.
In this area, we used the Midas Rex drill to remove a small portion of the
lamina on either side to gain access to the dura and performed an extensive
laminotomy from T-12 to T-1, removing the remaining thoracic spine and
preserving the spinous process and lamina. We similarly controlled any
epidural bleeding with FloSeal, Cottonoid patties, and bone wax. Meticulous
hemostasis was again established. We carefully opened the dura in the midline
with a #15-blade, elevating it off of the spinal cord. As we retracted the
dura, it was clear that some of the tumor was gelatinous, and it extruded
itself from the midline myelotomy. Inferiorly, we identified the area of the
cord, which we felt was most suspicious for the terminal hydromyelia.
Throughout the procedure, we kept the area of cord in which we did not work
covered with moist Cottonoid sponges. We performed a midline myelotomy at
approximately T-12, L-1 and entered into the terminal syrinx. This, again,
gave us access to the inferior nodular portion of the tumor. In this area,
the tumor was slightly more firm. Throughout the procedure, multiple biopsies
were taken and reviewed with Pathology, and they were felt to be consistent
with a low-grade tumor. Throughout the procedure, tumor was preserved for
special tumor bank studies, and specimens were preserved throughout the
procedure from different areas for permanent pathologic examination.
We continued to open the cord cephalad. As indicated, in some areas, the
tumor was gelatinous, and in other areas, it was firm. By using the CUSA and
intermittently checking evoked potentials, we slowly began debulking tumor
centrally. The cord was retracted with fine Prolene sutures on Hartman's
hemostats.
As we continued working, it was noted that the motor evoked potentials in the
right upper extremity had returned. We could not state the function in the
lower extremities, as preoperatively, neither motor or somatosensory evoked
potentials were obtainable.
By slowly removing tumor centrally, we performed a rather extensive debulking
of the tumor. Throughout the procedure, the removal was tedious. In the
midthoracic area, there was no evidence of a plane that could be defined
between tumor and normal cord. In fact, on the basis of the MR scan, the
entire cord was replaced by tumor. This clearly could not have been the case,
and therefore, we were somewhat cautious in how extensive our removal was in
the midthoracic area. However, both above and below, a rather aggressive
removal of tumor was carried out. In some areas, we could define an
interface, and in other areas, it could not be found.
The duration of the resection was exceptionally long, probably exceeding 5 to
6 hours. After completing the dissection and determining that the evoked
potentials had actually improved, we decided that we could not determine an
interface between normal and abnormal tissue and decided that further
resection would only leave the risk of complete paralysis.
We irrigated copiously with saline and Bacitracin solution. All brain cotton
was removed. Meticulous hemostasis was established with the bipolar cautery.
The pial retraction sutures were removed. Using a #6-0 Maxon, we
intermittently closed the pial surface, leaving an opening at the proximal and
at the distal area of syringomyelia. This was done to allow fluid to exit the
spinal central canal.
We continued our irrigation with warm Physiosol and again checked the evoked
potentials. They remained improved in the right upper extremity.
The dura was closed with a running #5-0 Maxon suture. We then irrigated the
dura copiously with antibiotic solution. Multiple holes were drilled in the
lamina, and corresponding holes in the spinous process and lamina. The lamina
was reattached using interrupted #2-0 and #3-0 Surgilon suture in multiple
sites, giving a rather rigid alignment and fixation.
We obtained hemostasis on the muscle with the bipolar cautery. We removed all
the retractors. We then closed the muscle in an interrupted fashion with #2-0
and #3-0 Vicryl, the subcutaneous tissue with running #3-0 Vicryl, and the
skin with running #4-0 Monocryl. The duration of the procedure was probably 8
to 9 hours. At the end of the procedure, Xeroform gauze, Telfa and Tegaderm
dressings were applied. All electrodes were removed. The patient was turned
supine.
She was left intubated and transferred to the Intensive Care Unit in stable
but guarded condition.