Accepted Manuscript CSF Happens Michelle J. Clarke, M.D. William E. Krauss, M.D. PII:
S1878-8750(14)00222-8
DOI:
10.1016/j.wneu.2014.03.009
Reference:
WNEU 2297
To appear in:
World Neurosurgery
Received Date: 3 December 2013 Accepted Date: 4 March 2014
Please cite this article as: Clarke MJ, Krauss WE, CSF Happens, World Neurosurgery (2014), doi: 10.1016/j.wneu.2014.03.009. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
Perspective: CSF Happens Michelle J. Clarke M.D., and William E. Krauss, M.D. Department of Neurologic Surgery, Mayo Clinic, Rochester MN
SC
RI PT
Corresponding Author: Michelle Clarke Department of Neurosurgery, Go8S Mayo Clinic Rochester MN 55905 507-284-6840 Fax: 507-284-5206 [email protected]
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M AN U
Inadvertent durotomies and intraoperative cerebrospinal fluid (CSF) leaks are an unfortunate fact of life for surgeons performing lumbar spine surgeries. Unfortunately, these surgical misadventures may negatively affect patient outcome, with issues ranging from postural headaches and persistent pseudomeningoceles to meningitis and intracranial hemorrhage. Additionally, operative repair of the dural rent increases operative time, post-operative bedrest extends length of stay, and persistent leakage may require additional operative interventions for resolution. Like many accidents, avoidance is the best strategy. However, when CSF does happen, a facile operative strategy and postoperative care plan likely improves outcome.
AC C
EP
In this issue of World Neurosurgery, Dr. Fessler and colleagues present a mixed retrospective series of simple lumbar decompressions to compare the rate and clinical impact of spinal fluid leaks in minimally invasive spine surgery (MISS) and open surgeries. They note that the MISS cases had a lower rate of CSF leaks, and only patients in the open cohort required revision surgery or lumbar drainage. This is the largest series to date broaching the topic of CSF leak in MIS vs. open procedures, but limitations to the series remain, specifically in the comparison open surgical cohort. Eleven surgeons participated in this series, with 4 primarily performing the MISS procedures and 7 primarily involved in the open surgeries. However, it is questionable whether the surgeon’s expertise was similar between groups. While not elaborated, 95% (303/319) of the MISS cases were performed by surgeons described as “mainly spine” (defined as performing over 20 cases per year), while only 70% (383/544) of open surgeries were performed by “mainly spine” surgeons (Table 1). Even in such “bread and butter” operations as lumbar surgery for spinal stenosis, low volume surgeons have demonstrated a significantly higher complication rate than high-volume surgeons(1). Additionally, as this report involves an experienced MISS surgical team including one of the world’s preeminent MISS surgeons, it is difficult to consider this a valid comparison to a mixed group of open surgeons with varying experience.
ACCEPTED MANUSCRIPT
M AN U
SC
RI PT
This apparent difference in surgical specialization may result in an increase in intraoperative complications. Indeed, the reported open CSF leak rate of 9% is at the high end of the published range for previously unoperated patients (2-6, 8-10). However, it is the aftermath of an intradural cerebrospinal fluid leak which may make experience more valuable, and postoperative management decisions made by a less experienced team could worsen patient outcomes. For instance, this study reports a reoperation rate in patients with CSF leak following open surgery of 24.4% (12/49 patients), which is well beyond the 1.8-8.0% reported rate(2, 5). It is also curious that in the open cases only 75% of patients with spinal fluid leaks had spinal fluid visualized intraoperatively. Although occult leaks can occur and become symptomatic (indeed, 2 such patients were also noted in the MISS group) this seems to be a surprisingly large number, with even the authors noting a published rate of 6.8% of cases. Obviously, if not identified intraoperatively, no primary repair could be attempted at the index procedure, potentially making postoperative symptomatology more prominent. If suspected, these occult CSF leaks were confirmed by imaging demonstrating pseudomeningocele, and as the authors note, may have led to differences in postoperative imaging studies between the two groups. Additionally, it is not confirmed that these pseudomeningocele were truly due to occult CSF and not simply seromas. Again, this may be related to a less experienced open surgical team.
AC C
EP
TE D
As open surgeons with a high-volume of simple lumbar cases, we were interested in the number of invasive leak-related postoperative interventions. Delving into the morbidity and mortality data of MJC’s practice, over a 3-year period, 316 lumbar laminectomies/discectomies (both revision and virgin) were performed. Of this cohort, only one patient was returned to the OR for wound revision due to CSF leak (0.3%), no patients had a blood patch or lumbar drainage. One additional patient was reoperated due to persistent radiculopathy and “mass” noted on imaging studies near the site of a known leak. This patient was found to have a strangulated nerve root which had herniated through an incompletely approximated incidental durotomy, and was improved following a very challenging reexploration and repair. This difference may simply be related to experience with the open procedures and their complications. It is our practice to promptly repair durotomies with excellent exposure and direct repair with suture. If direct repair is impossible, a fascial patch or muscle pledget is used to close the defect and a dural sealant may be applied. However, the primary defense in these cases is a superior fascial closure and good approximation of the lower wound layers. In many cases, we close fascia with interrupted sutures and run another stitch overtop to reinforce again, taking special care at either end of the wound or even lengthening the skin incision slightly to ensure tight fascial closure. While this does extend the operating time, in general we don’t think it exceeds the MISS procedure length noted in this paper (in fact, the authors did not find a statistically significant difference between MISS and open leak cases, despite no need for a repair in MISS cases).
ACCEPTED MANUSCRIPT
Postoperatively, we suggest but do not mandate the patient lie flat overnight or in the case of headache, but plan on mobilizing them the following day. Of note, we do not tolerate postoperative gluing or oversewing the incision: if CSF has broached the skin, I insist on reexploring and reinforcing the inadequately reinforced fascial layer at a minimum.
M AN U
SC
RI PT
Our own experience with the postoperatively strangulated nerve roots and arachnoiditis in patients with incidental durotomies is not addressed in this paper. Long-term follow-up would be interesting to determine whether there is any root egress in the setting of an unrepaired MISS durotomy as I have seen. I imagine this complication is rare; but, I would be curious if the incidence is higher as these tears are intentionally not approximated. Post-operative radicular symptoms in patients with known leaks in both cohorts would be interesting, although likely require much higher numbers due to their rarity. Although not statistically significant, there were more patients with spinal cord stimulators implanted in the MISS group. It is certainly a reach to expect these were needed due to herniated nerve roots, but exploring this question would be a fascinating extension of this paper.
TE D
Secondly, it is theorized that arachnoiditis is exacerbated by blood in the CSF space(11), which commonly occurs in the setting of a durotomy. As spontaneous CSF leaks can result in superficial siderosis(7) due to hemosiderin deposition without obvious active bleeding, is there any long-term increased incidence of arachnoiditis or other sequela in cases in which the dura is intentionally unrepaired? It may well be possible that the dead space is so thoroughly obliterated upon retractor removal that it acts as a vascularized muscle pledget and that this concern is not relevant, but as yet remains unproven.
AC C
EP
The authors do note that CSF leaks that occur in MISS cases are less likely to become symptomatic than those occurring in open cases. This statement concurs with other published reports. Indeed, the authors elegantly explain that it is likely a decrease in dead space that the smaller MISS surgical corridor offers which precludes fluid collection or wound extravasation. Again, based on surgical experience and a large number of unrecognized leaks in the open cohort, this may be exaggerated although it is likely valid. While a multilayered closure and tight fascial sutures due wonders to prevent CSF extravasation and reduce potential pseudomeningocele size, the tissue approximation is not as robust as that offered by simply removing a tubular retractor. It would be interesting to have more comprehensive long-range follow-up on these patients although it is beyond the scope of this study. Additional immediate complications note a higher rate of infection in the open cohort although this did not reach statistical significance. Likewise, the recorded long-term sequela of fusions, adjacent segment disease, and spinal cord stimulator placement also do not reach statistical significance. However it would be very valuable to obtain patient reported outcomes data on both leak cohorts to determine whether there is a
ACCEPTED MANUSCRIPT
difference in long-term complications of CSF leak based on surgical approach, and we hope the authors will continue to explore this in their large series.
RI PT
The authors should be commended on their openness to discuss surgical complications and their clinical sequela. This series provides important information about CSF leaks in both open and MISS simple spine procedures, although the reader should use caution in directly comparing the two cohorts.
References
5.
6.
7.
8.
9.
10. 11.
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M AN U
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TE D
3.
EP
2.
Dasenbrock H, Clarke M, Witham T, Sciubba D, Gokaslan Z, Bydon A: The impact of provider volume on the outcomes after surgery for lumbar spinal stenosis. Neurosurgery 70:1346-1353, 2012. Jankowitz B, Atteberry D, Gerszten P, P PK, Cheng B, Faught R, Welch W: Effect of fibrin glue on the prevention of persistent cerebral spinal fluid leakage after incidental durotomy during lumbar spinal surgery. Eur Spine J 18:116-1174, 2009. JC Wang HB, DK Riew: Dural tears secondary to operations on the lumbar spine: Management and results after two-year-minimum follow-up of 88 patients. J Bone Joint Surg (Am) 80:1728, 1998. Jr FC, Girardi F, Sangani P, Parvataneni H, Cadag S, Sandhu H: Incidental durotomy in spine surgery. Spine (Phila Pa 1976) 25:2663-2667, 2000. Khan M, Rihn J, Steele G, R RD, 3rd WD, Kang J, Lee J: Postoperative management protocol for incidental dural tears during degenerative lumbar spine surgery: a review of 3183 consecutive degenerative lumbar cases. Spine (Phila Pa 1976) 31, 2006. Kotilainen E, Valtonen S, Carlson C: Microsurgical treatment of lumbar disc herniation: follow-up of 237 patients. Acta Neurochir (Wien) 120:143-149, 1992. Miller G, Piepgras D, mokri B: A unifying hypothesis for a patient with superficial siderosis, low-pressure headache, intraspinal cyst, back pain, and prominent vascularity. J Neurosurg 113:97-101, 2010. Rampersaud Y, Moro E, Neary M, White K, Lewis S, Massicotte E, Fehlings M: Intraoperative adverse events and related postoperative complications in spine surgery: implications for enhancing patient safety founded on evidence-based protocols. Spine (Phila Pa 1976) 31:1503-1510, 2006. Saxler G, Kramer J, Barden B, Kurt A, Pförtner J, Bernsmann K: The long-term clinical sequelae of incidental durotomy in lumbar disc surgery. Spine 30:2298-2302, 2005. Tafazal S, Sell P: Incidental durotomy in lumbar spine surgery: incidence and management. Eur J Spine 14:287-290, 2005. Whetstone K, crane D: Cauda equina syndrome resulting from lumbar arachnoiditis after intracranial subarachnoid hemorrhage: a case report. PMR 5:539-541, 2013.
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ACCEPTED MANUSCRIPT
S1878-8750(14)00222-8
DOI:
10.1016/j.wneu.2014.03.009
Reference:
WNEU 2297
To appear in:
World Neurosurgery
Received Date: 3 December 2013 Accepted Date: 4 March 2014
Please cite this article as: Clarke MJ, Krauss WE, CSF Happens, World Neurosurgery (2014), doi: 10.1016/j.wneu.2014.03.009. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
ACCEPTED MANUSCRIPT
Perspective: CSF Happens Michelle J. Clarke M.D., and William E. Krauss, M.D. Department of Neurologic Surgery, Mayo Clinic, Rochester MN
SC
RI PT
Corresponding Author: Michelle Clarke Department of Neurosurgery, Go8S Mayo Clinic Rochester MN 55905 507-284-6840 Fax: 507-284-5206 [email protected]
TE D
M AN U
Inadvertent durotomies and intraoperative cerebrospinal fluid (CSF) leaks are an unfortunate fact of life for surgeons performing lumbar spine surgeries. Unfortunately, these surgical misadventures may negatively affect patient outcome, with issues ranging from postural headaches and persistent pseudomeningoceles to meningitis and intracranial hemorrhage. Additionally, operative repair of the dural rent increases operative time, post-operative bedrest extends length of stay, and persistent leakage may require additional operative interventions for resolution. Like many accidents, avoidance is the best strategy. However, when CSF does happen, a facile operative strategy and postoperative care plan likely improves outcome.
AC C
EP
In this issue of World Neurosurgery, Dr. Fessler and colleagues present a mixed retrospective series of simple lumbar decompressions to compare the rate and clinical impact of spinal fluid leaks in minimally invasive spine surgery (MISS) and open surgeries. They note that the MISS cases had a lower rate of CSF leaks, and only patients in the open cohort required revision surgery or lumbar drainage. This is the largest series to date broaching the topic of CSF leak in MIS vs. open procedures, but limitations to the series remain, specifically in the comparison open surgical cohort. Eleven surgeons participated in this series, with 4 primarily performing the MISS procedures and 7 primarily involved in the open surgeries. However, it is questionable whether the surgeon’s expertise was similar between groups. While not elaborated, 95% (303/319) of the MISS cases were performed by surgeons described as “mainly spine” (defined as performing over 20 cases per year), while only 70% (383/544) of open surgeries were performed by “mainly spine” surgeons (Table 1). Even in such “bread and butter” operations as lumbar surgery for spinal stenosis, low volume surgeons have demonstrated a significantly higher complication rate than high-volume surgeons(1). Additionally, as this report involves an experienced MISS surgical team including one of the world’s preeminent MISS surgeons, it is difficult to consider this a valid comparison to a mixed group of open surgeons with varying experience.
ACCEPTED MANUSCRIPT
M AN U
SC
RI PT
This apparent difference in surgical specialization may result in an increase in intraoperative complications. Indeed, the reported open CSF leak rate of 9% is at the high end of the published range for previously unoperated patients (2-6, 8-10). However, it is the aftermath of an intradural cerebrospinal fluid leak which may make experience more valuable, and postoperative management decisions made by a less experienced team could worsen patient outcomes. For instance, this study reports a reoperation rate in patients with CSF leak following open surgery of 24.4% (12/49 patients), which is well beyond the 1.8-8.0% reported rate(2, 5). It is also curious that in the open cases only 75% of patients with spinal fluid leaks had spinal fluid visualized intraoperatively. Although occult leaks can occur and become symptomatic (indeed, 2 such patients were also noted in the MISS group) this seems to be a surprisingly large number, with even the authors noting a published rate of 6.8% of cases. Obviously, if not identified intraoperatively, no primary repair could be attempted at the index procedure, potentially making postoperative symptomatology more prominent. If suspected, these occult CSF leaks were confirmed by imaging demonstrating pseudomeningocele, and as the authors note, may have led to differences in postoperative imaging studies between the two groups. Additionally, it is not confirmed that these pseudomeningocele were truly due to occult CSF and not simply seromas. Again, this may be related to a less experienced open surgical team.
AC C
EP
TE D
As open surgeons with a high-volume of simple lumbar cases, we were interested in the number of invasive leak-related postoperative interventions. Delving into the morbidity and mortality data of MJC’s practice, over a 3-year period, 316 lumbar laminectomies/discectomies (both revision and virgin) were performed. Of this cohort, only one patient was returned to the OR for wound revision due to CSF leak (0.3%), no patients had a blood patch or lumbar drainage. One additional patient was reoperated due to persistent radiculopathy and “mass” noted on imaging studies near the site of a known leak. This patient was found to have a strangulated nerve root which had herniated through an incompletely approximated incidental durotomy, and was improved following a very challenging reexploration and repair. This difference may simply be related to experience with the open procedures and their complications. It is our practice to promptly repair durotomies with excellent exposure and direct repair with suture. If direct repair is impossible, a fascial patch or muscle pledget is used to close the defect and a dural sealant may be applied. However, the primary defense in these cases is a superior fascial closure and good approximation of the lower wound layers. In many cases, we close fascia with interrupted sutures and run another stitch overtop to reinforce again, taking special care at either end of the wound or even lengthening the skin incision slightly to ensure tight fascial closure. While this does extend the operating time, in general we don’t think it exceeds the MISS procedure length noted in this paper (in fact, the authors did not find a statistically significant difference between MISS and open leak cases, despite no need for a repair in MISS cases).
ACCEPTED MANUSCRIPT
Postoperatively, we suggest but do not mandate the patient lie flat overnight or in the case of headache, but plan on mobilizing them the following day. Of note, we do not tolerate postoperative gluing or oversewing the incision: if CSF has broached the skin, I insist on reexploring and reinforcing the inadequately reinforced fascial layer at a minimum.
M AN U
SC
RI PT
Our own experience with the postoperatively strangulated nerve roots and arachnoiditis in patients with incidental durotomies is not addressed in this paper. Long-term follow-up would be interesting to determine whether there is any root egress in the setting of an unrepaired MISS durotomy as I have seen. I imagine this complication is rare; but, I would be curious if the incidence is higher as these tears are intentionally not approximated. Post-operative radicular symptoms in patients with known leaks in both cohorts would be interesting, although likely require much higher numbers due to their rarity. Although not statistically significant, there were more patients with spinal cord stimulators implanted in the MISS group. It is certainly a reach to expect these were needed due to herniated nerve roots, but exploring this question would be a fascinating extension of this paper.
TE D
Secondly, it is theorized that arachnoiditis is exacerbated by blood in the CSF space(11), which commonly occurs in the setting of a durotomy. As spontaneous CSF leaks can result in superficial siderosis(7) due to hemosiderin deposition without obvious active bleeding, is there any long-term increased incidence of arachnoiditis or other sequela in cases in which the dura is intentionally unrepaired? It may well be possible that the dead space is so thoroughly obliterated upon retractor removal that it acts as a vascularized muscle pledget and that this concern is not relevant, but as yet remains unproven.
AC C
EP
The authors do note that CSF leaks that occur in MISS cases are less likely to become symptomatic than those occurring in open cases. This statement concurs with other published reports. Indeed, the authors elegantly explain that it is likely a decrease in dead space that the smaller MISS surgical corridor offers which precludes fluid collection or wound extravasation. Again, based on surgical experience and a large number of unrecognized leaks in the open cohort, this may be exaggerated although it is likely valid. While a multilayered closure and tight fascial sutures due wonders to prevent CSF extravasation and reduce potential pseudomeningocele size, the tissue approximation is not as robust as that offered by simply removing a tubular retractor. It would be interesting to have more comprehensive long-range follow-up on these patients although it is beyond the scope of this study. Additional immediate complications note a higher rate of infection in the open cohort although this did not reach statistical significance. Likewise, the recorded long-term sequela of fusions, adjacent segment disease, and spinal cord stimulator placement also do not reach statistical significance. However it would be very valuable to obtain patient reported outcomes data on both leak cohorts to determine whether there is a
ACCEPTED MANUSCRIPT
difference in long-term complications of CSF leak based on surgical approach, and we hope the authors will continue to explore this in their large series.
RI PT
The authors should be commended on their openness to discuss surgical complications and their clinical sequela. This series provides important information about CSF leaks in both open and MISS simple spine procedures, although the reader should use caution in directly comparing the two cohorts.
References
5.
6.
7.
8.
9.
10. 11.
SC
M AN U
4.
TE D
3.
EP
2.
Dasenbrock H, Clarke M, Witham T, Sciubba D, Gokaslan Z, Bydon A: The impact of provider volume on the outcomes after surgery for lumbar spinal stenosis. Neurosurgery 70:1346-1353, 2012. Jankowitz B, Atteberry D, Gerszten P, P PK, Cheng B, Faught R, Welch W: Effect of fibrin glue on the prevention of persistent cerebral spinal fluid leakage after incidental durotomy during lumbar spinal surgery. Eur Spine J 18:116-1174, 2009. JC Wang HB, DK Riew: Dural tears secondary to operations on the lumbar spine: Management and results after two-year-minimum follow-up of 88 patients. J Bone Joint Surg (Am) 80:1728, 1998. Jr FC, Girardi F, Sangani P, Parvataneni H, Cadag S, Sandhu H: Incidental durotomy in spine surgery. Spine (Phila Pa 1976) 25:2663-2667, 2000. Khan M, Rihn J, Steele G, R RD, 3rd WD, Kang J, Lee J: Postoperative management protocol for incidental dural tears during degenerative lumbar spine surgery: a review of 3183 consecutive degenerative lumbar cases. Spine (Phila Pa 1976) 31, 2006. Kotilainen E, Valtonen S, Carlson C: Microsurgical treatment of lumbar disc herniation: follow-up of 237 patients. Acta Neurochir (Wien) 120:143-149, 1992. Miller G, Piepgras D, mokri B: A unifying hypothesis for a patient with superficial siderosis, low-pressure headache, intraspinal cyst, back pain, and prominent vascularity. J Neurosurg 113:97-101, 2010. Rampersaud Y, Moro E, Neary M, White K, Lewis S, Massicotte E, Fehlings M: Intraoperative adverse events and related postoperative complications in spine surgery: implications for enhancing patient safety founded on evidence-based protocols. Spine (Phila Pa 1976) 31:1503-1510, 2006. Saxler G, Kramer J, Barden B, Kurt A, Pförtner J, Bernsmann K: The long-term clinical sequelae of incidental durotomy in lumbar disc surgery. Spine 30:2298-2302, 2005. Tafazal S, Sell P: Incidental durotomy in lumbar spine surgery: incidence and management. Eur J Spine 14:287-290, 2005. Whetstone K, crane D: Cauda equina syndrome resulting from lumbar arachnoiditis after intracranial subarachnoid hemorrhage: a case report. PMR 5:539-541, 2013.
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ACCEPTED MANUSCRIPT
