Are Guidelines Important? Results of a Prospective Quality Improvement Lumbar Fusion Project.

BACKGROUND: United States (U.S.) healthcare is a volume-based inefficient delivery system. Value requires the consideration of quality, which is lacking in most healthcare disciplines. OBJECTIVE: To assess whether patients who met specific evidence-based medicine (EBM)-based criteria preoperatively for lumbar fusion would achieve higher rates of achieving the minimal clinical important difference (MCID) than those who did not meet the EBM indications. METHODS: All elective lumbar fusion cases, March 2018 to August 2019, were prospectively evaluated and categorized based on EBM guidelines for surgical indications. The MCID was defined as a reduction of ≥5 points in Oswestry Disability Index (ODI). Multiple logistic regression identified multivariable-adjusted odds ratio of EBM concordance. RESULTS: A total of 325 lumbar fusion patients were entered with 6-mo follow-up data available for 309 patients (95%). The median preoperative ODI score was 24.4 with median 6-mo improvement of 7.0 points (P < .0001). Based on ODI scores, 79.6% (246/309) improved, 3.8% (12/309) had no change, and 16% (51/309) worsened. A total of 191 patients had ODI improvement reaching the MCID. 93.2% (288/309) cases were EBM concordant, while 6.7% (21/309) were not.In multivariate analysis, EBM concordance (P = .0338), lower preoperative ODI (P < .001), lower ASA (American Society of Anesthesiologists) (P = .0056), and primary surgeries (P = .0004) were significantly associated with improved functional outcome. EBM concordance conferred a 3.04 (95% CI 1.10-8.40) times greater odds of achieving MCID in ODI at 6 mo (P = .0322), adjusting for other factors. CONCLUSION: This analysis provides validation of EBM guideline criteria to establish optimal patient outcomes. The EBM concordant patients had a greater than 3 times improved outcome compared to those not meeting EBM fusion criteria.

Resected WHO grade I meningioma and predictors of local control.

INTRODUCTION: Despite optimal surgical resection, meningiomas may recur, with increasing grade and the degree of resection being predictive of risk. We hypothesize that an increasing Ki67 correlates with a higher risk of recurrence of resected WHO grade I meningiomas. METHODS: The study population consisted of patients with resected WHO grade 1 meningiomas in locations outside of the base of skull. Digitally scanned slides stained for Ki67 were analyzed using automatic image analysis software in a standardized fashion. RESULTS: Recurrence was observed in 53 (17.7%) of cases with a median follow up time of 25.8 months. Ki67 ranged from 0 to 30%. Median Ki67 was 5.1% for patients with recurrence and 3.5% for patients without recurrence. In unadjusted analyses, high Ki-67 (≥ 5 vs. < 5) vs. ≥ 5) was associated with over a twofold increased risk of recurrence (13.1% vs. 27% respectively; HR 2.1731; 95% CI [1.2534, 3.764]; p = 0.006). After Adjusting for patient or tumor characteristics, elevated Ki-67 remained significantly correlated with recurrence. Grade 4 Simpson resection was noted in 71 (23.7%) of patients and it was associated with a significantly increased risk of recurrence (HR 2.56; 95% CI [1.41, 4.6364]; p = 0.002). CONCLUSIONS: WHO grade 1 meningiomas exhibit a significant rate of recurrence following resection. While Ki-67 is not part of the WHO grading criteria of meningiomas, a value greater than 5% is an independent predictor for increased risk of local recurrence following surgical resection.

Low Yield of Cerebral Angiography in Adequately Occluded Aneurysms After Flow Diversion.

BACKGROUND: Flow diversion has emerged as a highly effective treatment for intracranial aneurysms. OBJECTIVE: To assess the yield of further angiographic follow-up in aneurysms that have achieved adequate occlusion after treatment with the Pipeline Embolization Device (PED; Medtronic Inc, Dublin, Ireland). METHODS: This is a single-institution, retrospective study. Inclusion criteria were as follows: (1) patients with 1 or more aneurysms treated with PED, (2) available short-term (<12 mo) follow-up digital subtraction angiography (DSA), (3) complete (100%) or near-complete (>95%) occlusion on short-term follow-up DSA, and (4) available further angiographic follow-up (DSA, Magnetic Resonance Angiography (MRA), or Computed Tomography Angiography (CTA)). RESULTS: A total of 146 patients were identified. Aneurysm size was 8.4 ± 5.1 mm on average. Mean angiographic follow-up time was 29.7 ± 12.2 mo. On short-term follow-up DSA images, 132 (90.4%) had complete aneurysm occlusion and 14 (9.6%) had near-complete occlusion. Four patients (3%) had further DSA follow-up alone, 30 patients (21%) had further DSA and MRA/CTA follow-up, and 112 patients (76%) had further MRA/CTA follow-up alone. On further angiographic follow-up (DSA, MRA, and/or CTA), no patient had a decrease in the degree of aneurysm occlusion (recurrence) or required retreatment. Of the 14 patients with near-complete occlusion on initial DSA images, 7 patients (50%) progressed to complete aneurysm occlusion on further angiographic follow-up. CONCLUSION: This study did not find any diagnostic yield in repeating cerebral angiography in adequately occluded aneurysms with the PED. We do not recommend repeat angiographic follow-up once aneurysms have achieved complete occlusion with the PED unless clinically warranted.

Suture Choice in Lumbar Dural Closure Contributes to Variation in Leak Pressures: Experimental Model.

STUDY DESIGN: Open-label laboratory investigational study; non-animal surgical simulation. OBJECTIVE: The authors perform a comparison of dural closure strength in a durotomy simulator across 2 different suture materials. SUMMARY OF BACKGROUND DATA: Incidental durotomy leading to persistent cerebrospinal fluid leak adds considerable morbidity to spinal procedures, often complicating routine elective lumbar spinal procedures. Using an experimental durotomy simulation, the authors compare the strength of closure using Gore-Tex with other suture types and sizes, using various closure techniques. METHODS: A comparison of dural closures was performed through an analysis of the peak pressure at which leakage occurred from a standardized durotomy closure in an established cerebrospinal fluid repair model with a premade L3 laminectomy. Nurolon was compared with Gore-Tex sutures sizes (for Gore-Tex, CV-6/5-0 and CV-5/4-0 was compared with Nurolon 4-0, 5-0, and 6-0). RESULTS: Thirty-six trials were performed with Nurolon 4-0, 5-0, and 6-0, whereas 21 trials were performed for 4-0 and 5-0 Gore-Tex. The mean peak pressure at which fluid leakage was observed was 21 cm H2O for Nurolon and 34 cm H2O for Gore-Tex. Irrespective of suture choice, all trials were grouped by closure technique: running suture, locked continuous, and interrupted suture. No significant difference was noted between the groups. For each of the 3 trials groups by closure technique, running, locked continuous, and interrupted, Gore-Tex closures had a significantly higher peak pressure to failure. Interrupted Gore-Tex was significantly higher than Interrupted Nurolon (P=0.007), running Gore-Tex was significantly higher than running Nurolon (P=0.034), and locked Gore-Tex was significantly higher than locked Nurolon (P=0.014). CONCLUSIONS: Durotomy closure in the lumbar spine with Gore-Tex suture may be a reasonable option for providing a watertight closure. In this laboratory study, Gore-Tex suture provided watertight dural closures that withstood higher peak pressures.

Matched Comparison of Flow Diversion and Coiling in Small, Noncomplex Intracranial Aneurysms.

BACKGROUND: Flow diversion is typically reserved for large, giant, or morphologically complex aneurysms. Coiling remains a first-line treatment for small, morphologically simple aneurysms. OBJECTIVE: To compare coiling and flow diversion in small, uncomplicated intracranial aneurysms (typically amenable to coiling). METHODS: Forty patients treated with the pipeline embolization device (PED) for small (<10 mm), morphologically simple aneurysms that would have also been amenable to coiling were identified. These patients were matched in a 1:1 fashion with 40 patients with comparable aneurysms treated with coiling. Matching was based on age, gender, aneurysm size, and aneurysm morphology. RESULTS: The 2 groups were comparable with regard to baseline characteristics including age, gender, and aneurysm size. The complication rate did not differ between the 2 groups (2.5% with coiling vs 5% with PED; P = .6). Multivariate analysis did not identify any predictor of complications. Complete occlusion (100%) at follow-up was significantly higher in patients treated with PED (70%) than coiling (47.5%, P = .04). In multivariate analysis, treatment with PED predicted aneurysm obliteration ( P = .04). A significantly higher proportion of coiled patients (32.5%) required retreatment compared with flow diversion (5%, P = .003). In multivariate analysis, coiling predicted retreatment ( P = .006). All patients achieved a favorable outcome (modified Rankin Scale: 0-2) regardless of group. CONCLUSION: This matched analysis suggests that flow diversion provides higher occlusion rates, lower retreatment rates, and no additional morbidity compared with coiling in small, simple aneurysms amenable to both techniques. These results suggest a potential benefit for flow diversion over coiling even in small, uncomplicated aneurysms.

Management of cerebral cavernous malformations: from diagnosis to treatment.

Cerebral cavernous malformations are the most common vascular malformations and can be found in many locations in the brain. If left untreated, cavernomas may lead to intracerebral hemorrhage, seizures, focal neurological deficits, or headaches. As they are angiographically occult, their diagnosis relies on various MR imaging techniques, which detect different characteristics of the lesions as well as aiding in planning the surgical treatment. The clinical presentation and the location of the lesion are the most important factors involved in determining the optimal course of treatment of cavernomas. We concisely review the literature and discuss the advantages and limitations of each of the three available methods of treatment--microsurgical resection, stereotactic radiosurgery, and conservative management--depending on the lesion characteristics.

Intraoperative vancomycin use in spinal surgery: single institution experience and microbial trends.

STUDY DESIGN: Retrospective case series. OBJECTIVE: To demonstrate the microbial trends of spinal surgical site infections in patients who had previously received crystallized vancomycin in the operative bed. SUMMARY OF BACKGROUND DATA: Prior large, case control series demonstrate the significant decrease in surgical site infection with the administration of vancomycin in the wound bed. METHODS: A single institution, electronic database search was conducted for all patients who underwent spinal surgery who had received prophylactic crystalline vancomycin powder in the wound bed. Patients with a prior history of wound infection, intrathecal pumps, or spinal stimulators were excluded. RESULTS: A total of 981 consecutive patients (494 males, 487 females; mean age, 59.4 yr; range, 16-95 yr) were identified from January 2011 to June 2013. The average dose of vancomycin powder was 1.13 g (range, 1-6 g). Sixty-six patients (6.71%) were diagnosed with a surgical site infection, of which 51 patients had positive wound cultures (5.2%). Of the 51 positive cultures, the most common organism was Staphylococcus aureus. The average dose of vancomycin was 1.3 g in the 38 cases where a gram-positive organism was cultured. A number of gram-negative infections were encountered such as Serratia marcescens, Enterobacter aerogenes, Bacteroides fragilis, Enterobacter cloacae, Citrobacter koseri, and Pseudomonas aeruginosa. The average dose of vancomycin was 1.2 g in 23 cases where a gram-negative infection was cultured. Fifteen of the 51 positive cultures (29.4%) were polymicrobial. Eight (53%) of these 15 polymicrobial cultures contained 3 or more distinct organisms. CONCLUSION: Prophylactic intraoperative vancomycin use in the wound bed in spinal surgery may increase the incidence of gram-negative or polymicrobial spinal infections. The use of intraoperative vancomycin may correlate with postoperative seromas, due to the high incidence of nonpositive cultures. Large, randomized, prospective trials are needed to demonstrate causation and dose-response relationship.

Radiosurgery for the treatment of dominant hemisphere periventricular heterotopia and intractable epilepsy in a series of three patients.

Periventricular heterotopia (PVH) is a neuronal migration disorder characterized by masses of gray matter located along the lateral ventricles that commonly cause epilepsy. The benefit of surgical resection of the PVH has been demonstrated in case reports to date; however, the location of the PVH in the paratrigonal region of the lateral ventricles can present significant surgical challenges. Noninvasive modalities of ablating this epileptogenic focus must therefore be considered. We present a small series of three patients who underwent stereotactic radiosurgery (SRS) for inoperable unilateral dominant hemisphere PVHs in order to illustrate the potential benefits and risks of this treatment modality. A total dose of 37.5-65 Gy resulted in seizure freedom for at least 14 months at the time of their last follow-up, even in patients harboring a second independent epileptic focus. Whether intracranial electrode recording truly offers added value is therefore uncertain. The two patients who received higher radiation doses suffered from symptomatic radiation necrosis and associated cerebral edema, requiring further medical intervention, and persistent monocular visual loss in one patient. While a longer interval prior to re-treatment may have been attempted, neither patient demonstrated radiographic findings typically associated with seizure remission. Refractory epilepsy due to PVH may be successfully treated with radiation therapy; but further work is needed to define the optimal dosing parameters in order to lower toxicity to normal tissue.