Michael J. Cools, Carolyn S. Quinsey and Scott W. Elton
The choice of graft material for duraplasty in decompressions of Chiari malformations remains a matter of debate. The authors present a detailed technique for harvesting ligamenta nuchae, as well as the clinical and radiographic outcomes of this technique, in a case series.
The authors conducted a retrospective study evaluating the outcomes of Chiari malformation type I decompression and duraplasty in children aged 0–18 years at a single institution from 2013 to 2016. They collected both intraoperative and postoperative variables and compared them qualitatively to published data.
During the study period, the authors performed 25 Chiari malformation decompressions with ligamentum nuchae graft duraplasties. Of the 25 patients, 10 were females, and the mean age at surgery was 8.6 years (range 13 months to 18 years). The median operative time was 163 minutes (IQR 152–187 minutes), with approximately 10 minutes needed by a resident surgeon to harvest the graft. The mean length of stay was 3 nights (range 2–6 nights), and the mean follow-up was 12.6 months (range 0.5–43.5 months). One patient (4%) developed a CSF leak that was repaired using an oversewing patch. There were no postoperative pseudomeningoceles or infections. Of the 19 patients presenting with a syrinx, imaging showed improvement in 10 (53%) and 8 (42%) had stable syrinx size on imaging. Of 16 patients presenting with a symptomatic Chiari malformation, 14 (87.5%) experienced resolution of symptoms and in 1 (4%) symptoms remained the same. One patient (4%) presented with worsening syrinx and symptoms 1.5 months after initial surgery and underwent repeat decompression.
The authors describe a series of clinical and imaging outcomes of patients who underwent Chiari malformation decompression and duraplasty with a harvested ligamentum nuchae. The rates of postoperative CSF leak are similar to established techniques of autologous and artificial grafts, with similarly successful outcomes. Further study will be needed with larger patient cohorts to more directly compare duraplasty graft outcomes.
E. H. Botterell, W. M. Lougheed, J. W. Scott and S. L. Vandewater
William W. Scott, Jeffrey A. Fearon, Dale M. Swift and David J. Sacco
The optimal management of Chiari malformations in the setting of craniosynostosis is not well established. In this report the authors describe their outcomes with the combined technique of simultaneous suboccipital decompression (SOD) during posterior cranial vault remodeling (PCVR).
A retrospective review was performed of all patients undergoing PCVR and simultaneous SOD. Demographic data, diagnosis, imaging studies, operative intervention, and clinical follow-up were evaluated.
Thirty-four patients were identified as having undergone a simultaneous PCVR/SOD for Chiari malformation associated with craniosynostosis. Eighty-eight percent of these patients had syndromic, multisutural craniosynostosis, and the remaining patients had unilateral lambdoid craniosynostosis. There were no postoperative complications as a direct result from this combined procedure. Two patients required a subsequent direct approach for decompression of the Chiari malformation. The interval between these subsequent surgeries was 3 years and 19 months.
Chiari malformations are commonly associated with syndromic, complex craniosynostosis and isolated lambdoid craniosynostosis. In appropriately selected patients, a combined posterior cranial vault enlargement and SOD of the foramen magnum is associated with a low complication rate and appears to be an effective procedure.
S. Scott Lollis, Dudley J. Weider, Joseph M. Phillips and David W. Roberts
The goal of this study was to provide preliminary data regarding clinical and functional outcome, including postoperative morbidity, related to ventriculoperitoneal (VP) shunt insertion for refractory perilymphatic fistula.
The authors retrospectively reviewed the records of seven consecutive patients who had undergone VP shunt insertion for medically and surgically refractory perilymphatic fistula between 1996 and 2004. Patients were also contacted by telephone and asked to assess retrospectively their symptomatic improvement, changes in functional status, and changes in work status following shunt placement. Preoperative and postoperative functional statuses were assessed using a standardized instrument. In each patient, preoperative opening pressure was measured via lumbar puncture. Pressures ranged from 160 to 300 mm H2O, with a mean of 241 mm H2O.
All patients reported significant improvement in symptom severity following surgery. Two patients reported complete resolution of symptoms. Three patients were able to resume full-time work. Clinically significant improvement in functional status was noted in six of seven patients. All patients would recommend the procedure to others in a similar situation.
Data in this study suggest that some patients with disabling vertigo, tinnitus, and headache due to perilymphatic fistula, whose conventional medical and surgical therapies have failed to produce a cure, benefit from VP shunt insertion. The authors hypothesize that VP shunt placement blunts intracranial pressure increases, which would cause secondary elevations in perilymphatic fluid pressure. Shunt insertion reduces perilymph leakage into the middle ear and may permit closure of the fistula.
Nitish Agarwal, Mohit Agrawal and Dattaraj P. Sawarkar
Brian L. Hoh, Koji Hosaka, Daniel P. Downes, Kamil W. Nowicki, Erin N. Wilmer, Gregory J. Velat and Edward W. Scott
A small percentage of cerebral aneurysms rupture, but when they do, the effects are devastating. Current management of unruptured aneurysms consists of surgery, endovascular treatment, or watchful waiting. If the biology of how aneurysms grow and rupture were better known, a novel drug could be developed to prevent unruptured aneurysms from rupturing. Ruptured cerebral aneurysms are characterized by inflammation-mediated wall remodeling. The authors studied the role of stromal cell–derived factor-1 (SDF-1) in inflammation-mediated wall remodeling in cerebral aneurysms.
Human aneurysms, murine carotid artery aneurysms, and murine intracranial aneurysms were studied using immunohistochemistry. Flow cytometry analysis was performed on blood from mice developing carotid or intracranial aneurysms. The effect of SDF-1 on endothelial cells and macrophages was studied by chemotaxis cell migration assay and capillary tube formation assay. Anti–SDF-1 blocking antibody was given to mice and compared with control (vehicle)-administered mice for its effects on the walls of carotid aneurysms and the development of intracranial aneurysms.
Human aneurysms, murine carotid aneurysms, and murine intracranial aneurysms all expressed SDF-1, and mice with developing carotid or intracranial aneurysms had increased progenitor cells expressing CXCR4, the receptor for SDF-1 (p < 0.01 and p < 0.001, respectively). Human aneurysms and murine carotid aneurysms had endothelial cells, macrophages, and capillaries in the walls of the aneurysms, and the presence of capillaries in the walls of human aneurysms was associated with the presence of macrophages (p = 0.01). Stromal cell–derived factor-1 promoted endothelial cell and macrophage migration (p < 0.01 for each), and promoted capillary tube formation (p < 0.001). When mice were given anti–SDF-1 blocking antibody, there was a significant reduction in endothelial cells (p < 0.05), capillaries (p < 0.05), and cell proliferation (p < 0.05) in the aneurysm wall. Mice given anti–SDF-1 blocking antibody developed significantly fewer intracranial aneurysms (33% vs 89% in mice given control immunoglobulin G, respectively; p < 0.05).
These data suggest SDF-1 is associated with angiogenesis and inflammatory cell migration and proliferation in the walls of aneurysms, and may have a role in the development of intracranial aneurysms.
Matthew F. Gornet, Todd H. Lanman, J. Kenneth Burkus, Randall F. Dryer, Jeffrey R. McConnell, Scott D. Hodges and Francine W. Schranck
The authors assessed the 10-year clinical safety and effectiveness of cervical disc arthroplasty (CDA) to treat degenerative cervical spine disease at 2 adjacent levels compared to anterior cervical discectomy and fusion (ACDF).
A prospective, randomized, controlled, multicenter FDA-approved clinical trial was conducted comparing the low-profile titanium ceramic composite–based Prestige LP Cervical Disc (n = 209) at two levels with ACDF (n = 188). Ten-year follow-up data from a postapproval study were available on 148 CDA and 118 ACDF patients and are reported here. Clinical and radiographic evaluations were completed preoperatively, intraoperatively, and at regular postoperative follow-up intervals for up to 10 years. The primary endpoint was overall success, a composite variable that included key safety and efficacy considerations. Ten-year follow-up rates were 86.0% for CDA and 84.9% for ACDF.
From 2 to 10 years, CDA demonstrated statistical superiority over ACDF for overall success, with rates at 10 years of 80.4% versus 62.2%, respectively (posterior probability of superiority [PPS] = 99.9%). Neck Disability Index (NDI) success was also superior, with rates at 10 years of 88.4% versus 76.5% (PPS = 99.5%), as was neurological success (92.6% vs 86.1%; PPS = 95.6%). Improvements from preoperative results in NDI and neck pain scores were consistently statistically superior for CDA compared to ACDF. All other study effectiveness measures were at least noninferior for CDA compared to ACDF through the 10-year follow-up period, including disc height. Mean angular ranges of motion at treated levels were maintained in the CDA group for up to 10 years. The rates of grade IV heterotopic ossification (HO) at the superior and inferior levels were 8.2% and 10.3%, respectively. The rate of severe HO (grade III or IV) did not increase significantly from 7 years (42.4%) to 10 years (39.0%). The CDA group had fewer serious (grade 3–4) implant-related or implant/surgical procedure–related adverse events (3.8% vs 8.1%; posterior mean 95% Bayesian credible interval [BCI] of the log hazard ratio [LHR] −0.92 [−1.88, −0.01]). The CDA group also had statistically fewer secondary surgical procedures at the index levels (4.7%) than the ACDF group (17.6%) (LHR [95% BCI] −1.39 [−2.15, −0.61]) as well as at adjacent levels (9.0% vs 17.9%).
The Prestige LP Cervical Disc, implanted at two adjacent levels, maintains improved clinical outcomes and segmental motion 10 years after surgery and is a safe and effective alternative to fusion.
Clinical trial registration no.: NCT00637156 (clinicaltrials.gov)
William W. Scott, Steven Sharp, Stephen A. Figueroa, Christopher J. Madden and Kim L. Rickert
Screening of blunt vertebral artery (VA) injuries has increased since research has shown that they occur at a higher incidence than originally reported. Grade 1 and 2 injuries are the most common form of blunt VA injury. Proper screening, management, and follow-up of these injuries remain controversial. In this report, imaging, progression, treatment, and outcomes of Grade 1 and 2 blunt VA injuries were analyzed to better define their natural history and to establish a rational management plan based upon their risk of progression and cerebral infarct.
A retrospective review of all blunt traumatic carotid artery and VA injuries from December 2003 to April 2013 was performed. For the purposes of this report, focus was given to Grade 1 and 2 VA injuries. Grade 1 injuries were defined as a vessel lumen stenosis of less than 25%, and Grade 2 injuries were defined as vessel lumen stenosis between 25% and 50%. Demographic information, radiological imaging, number of images performed per individual, length of radiological follow-up, radiological outcome at the end of follow-up, treatment provided, and documentation of stroke or transient ischemic attack were recorded.
One hundred eighty-seven Grade 1 and 2 VA injuries in 143 patients were identified. Of these 143 patients, 120 with 152 Grade 1 or 2 blunt VA injuries were available for follow-up. The mean duration of follow-up was 40 days. Repeat imaging showed that 148 (97.4%) Grade 1 or 2 blunt VA injuries were stable, improved, or resolved on final follow-up imaging. Seventy-nine patients (66%) were treated with aspirin, whereas 35 patients (29%) received no treatment. The remaining patients were treated with other antiplatelet agents or anticoagulant medication. Neuroimaging demonstrated 2 cases (1.7%) with posterior circulation infarcts that were believed to be related to their blunt VA injuries, both of which occurred during the initial hospitalization and within the first 4 days after injury.
Although follow-up imaging showed progressive worsening without radiological improvement in only a small number of patients with low-grade blunt VA injuries, these findings did not correlate with adverse clinical outcome. The posttraumatic cerebral infarction rate of 1.7% may be overestimated, and the use of acetylsalicylic acid or other antiplatelet or anticoagulant medication did not correlate with radiological changes or rate of cerebral infarction. While these data suggest the possibility that these low-grade VA injuries may not require treatment or follow-up, future prospective studies are needed to make conclusive changes related to management.