Keywords
spine surgery - intraoperative durotomy - cerebrospinal fluid leakage - gore preclude
MVP dura substitute - repair
Introduction
Intraoperative durotomy or incidental durotomy (ID) can occur unintentionally during
spine surgery. ID can occur from the cervical levels to the lumbar region along the
spinal cord, but ID in the lumbar region is relatively common.[1] The incidence of ID can vary from 3 to 27% during lumbar spinal surgery.[2] Moreover, ID can occur more frequently in the revision/secondary operation than
in the primary operation.[3] ID that is inappropriately managed can result in secondary complications such as
cerebrospinal fluid (CSF) leakage, CSF cutaneous fistula, headache, pseudomeningocele,
arachnoiditis, meningitis, epidural abscess, and neurological deterioration.[1]
[4] Moreover, a persistent CSF leakage due to ID can also lead to a chronic pain disorder,
cranial nerve palsy, and radiculopathy.[1]
[4] To prevent these ID-related secondary complications, ID should be appropriately
managed before wound closure.
Several methods concerning the intraoperative repair of ID have been proposed. In
the cases where direct suture of the ID site is possible, a 6–0 or 7–0 needle is applied.
The needle hole should be covered with a fibrin glue sealant.[5] Nonpenetrating clips can also seal the puncture directly. In the cases where the
puncture is large enough, a muscle pouch, fascia pouch, and artificial dura sheet
can be used. Durotomy repair using a polyglactin acid sheet covered with fibril glue
seems to be an effective method.[5]
[6] Effective intraoperative repair of the durotomy using DuraGen has also been described.[3] However, to the best of our knowledge, reports on the intraoperative repair of ID
using Gore Preclude MVP Dura Substitute (W. L. Gore & Associates, Inc. Japan; henceforth
referred to as “MVP”) seem to be scant. In this study, we present our method to repair
intraoperative durotomy during spine surgery using the MVP.
Materials and Methods
A Representative Case
During the removal of granulation tissue on the dura, an ID occurred during additional
posterior lumbar intervertebral fixation surgery. The subsequent CSF leakage led us
to conclude that repair of the ID was necessary. We measured the dimensions of the
ID site. The MVP was designed to be twice the size of the ID site. The dura around
the ID site was circumferentially detached from the arachnoid membrane. Following
this, the MVP was inserted into the space between the dura and the arachnoid membrane.
Care was taken not to damage the arachnoid membrane. Subsequently, the MVP was stitched
to the dura using a 6–0 nylon yarn by penetrating the convex surface of the MVP. This
procedure was performed under an operative microscope. CSF leakage was not associated
with the Valsalva maneuver ([Fig. 1]).
Fig. 1 Intraoperative procedure of dural repair. (A) A durotomy occurred during granulation tissue excision from the lamina and dura.
Cerebrospinal fluid leakage was observed. (B, C) The size of the dura was measured. In this case, the dimension of the durotomy site
was 5 × 7 mm. (D) The dura was circumferentially detached from the arachnoid membrane. (E) The dimension of the MVP was approximately 10 × 14 mm. (F–I) The MVP was inserted into the space between the dura and arachnoid membrane. (J, K) The MVP was sutured to the dura using 6–0 nylon yarn. The nodes were made by penetrating
the convex surface of the MVP. Ar, arachnoid membrane; Ca, caudal; Cr, cranial; D,
dura; G, MVP (Gore Preclude MVP Dura Substitute).
ID repair using MVP was performed in five patients by three neurosurgeons. The method
was applied to a patient with refractory CSF leakage and four patients in the same
operation where an ID occurred. Bolheal (fibrin sealant), Neoveil sheet, fascia patch,
and DuraGen were also applied if required ([Table 1]).
Table 1
Five patients with intraoperative durotomy treated using Gore Preclude MVP Dura Substitute
|
Patients
|
Sex, age (y)
|
Preceded operation
|
Operation related to intraoperative durotomy
|
Preceded procedures to repair intraoperative durotomy
|
Additional procedures to repair durotomy
|
|
Patient 1
|
Male, 55
|
L2/L3 PLIF
|
L3/L4 PLIF
Removal of L2 screws
|
1 Neoveil and Bolheal
2 fascia patch (6–0 Prolene), Surgicel, Bolheal, and DuraGen
|
Bolheal, DuraGen, fascia and fatty tissue patch, and Neoveil
|
|
Patient 2
|
Female, 54
|
None
|
L4/L5 PLIF
|
None
|
None
|
|
Patient 3
|
Male, 76
|
L4/L5, L5/S1 PLIF
|
L3/L4 MD + laminectomy
|
None
|
Fascia patch
|
|
Patient 4
|
Female, 77
|
None
|
L3/L4, L4/L5 laminectomy
|
None
|
Bolheal, DuraGen, and Neoveil
|
|
Patient 5 (representative case)
|
Female, 81
|
MD
|
L3–S1 PLIF
|
None
|
Bolheal and Neoveil
|
Abbreviations: MD, microdiskectomy; PLIF, posterior lumbar intervertebral fixation.
Results
The intraoperative dural repair was achieved, and CSF leakage did not persist. Postoperative
complications related to ID did not occur.
Discussion
We described a simple and effective method to repair ID using the MVP. This method
successfully managed the incidental occurrence of durotomy and prevented secondary
complications associated with ID in lumbar surgery.
The MVP is an artificial dura mater like Gore-Tex. Gore-Tex is composed of an expanded
polytetrafluoroethylene (EPTEE) sheet.[7] After the utility of the EPTEE sheet to prevent postoperative fibrous ingrowth was
confirmed by experimental studies,[8]
[9] Gore-Tex was applied to clinical use.[10]
[11]
[12] However, Gore-Tex is associated with CSF leakage from needle holes on the surface
can be a disadvantage. To minimize the CSF leakage, small needles such as 6–0 or 7–0
are applied to suture Gore-Tex to an ID site.[3] Alternatively, ID repaired with nonpenetrating titanium clips is preferred.[13] Similar to Gore-Tex, the surface of the MVP is also composed of EPTEE. Moreover,
the three-layered MVP consists of a proprietary intermediate layer of fluoroelastomer
between two EPTEE layers. The intermediate layer works as an impermeable watertight
barrier owing to a self-sealing feature. Among the two outer layers, the surface attaching
to the neural tissue is relatively smooth and not adhesive and, hence, ensures flexibility.
The opposite surface is designed as an open pore structure that facilitates rapid
ingrowth of fibroblasts.[14]
In our method, the MVP was inserted in the space between the dura and arachnoid membrane
([Fig. 2]). For sufficient coverage of the ID site, the MVP was designed bigger than the size
of the ID site in the representative case. Since fixing MVP with a multinodes of 6–0
nylon yarn is associated with CSF leakage from the holes, only four nodes were used
for suturing the 6–0 nylon yarn anchoring the convex surface to the dura in our method.
Fig. 2 Schema of our method to repair intraoperative using MVP. The MVP was designed bigger
than the size of the durotomy. The MVP was anchored with 6–0 nylon to the dura. The
CSF pressure aids better attachment of MVP to the inner surface of the dura. This
condition seems favorable to prevent CSF leakage. CSF, cerebrospinal fluid; MVP, Gore
Preclude MVP Dura Substitute.
Our method to repair ID using the MVP seems to have the following advantages: (1)
minimization of CSF leakage from the node holes; (2) the open pore surface of the
MVP firmly attaches to the inner surface of the dura, facilitating rapid ingrowth
of fibroblasts; and (3) as the MVP is not tightly fixed to the dura, the flexibility
of the MVP is maintained. Thus, the MVP can adapt to the dural position and expansion
due to CSF pressure change associated with posture.
Since a long-term follow-up is lacking in this method, the patients undergoing our
method to repair ID using the MVP are now monitored in an outpatient clinic.
Conclusion
Our simple method of dural repair using the Gore Preclude MVP Dura Substitute is effective.
This method will be useful in improving the management of complications associated
with ID.
