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Background: Pelvic tilt (PT) is a compensatory mechanism for adult spinal deformity patients to mitigate sagittal imbalance. The association between preop PT and postop clinical and radiographic outcomes has not been well studied in patients undergoing minimally invasive adult deformity surgery., Objective: To evaluate clinical and radiographic outcomes in adult spinal deformity patients with high and low preoperative PT treated surgically using less invasive techniques., Methods: Retrospective case-control, institutional review board-approved study. A multicenter, minimally invasive surgery spinal deformity patient database was queried for 2-yr follow-up with complete radiographic and health-related quality of life (HRQOL) data. Hybrid surgery patients were excluded. Inclusion criteria were as follows: age > 18 and either coronal Cobb angle > 20, sagittal vertical axis > 5 cm, pelvic incidence-lumbar lordosis (PI-LL) > 10 or PT > 20. Patients were stratified by preop PT as per Schwab classification: low (PT< 20), mid (PT 20-30), or high (>30). Postoperative radiographic alignment parameters (PT, PI, LL, Cobb angle, sagittal vertical axis) and HRQOL data (Visual Analog Scale Back/Leg, Oswestry Disability Index) were evaluated and analyzed., Results: One hundred sixty-five patients had complete 2-yr outcomes data, and 64 patients met inclusion criteria (25 low, 21 mid, 18 high PT). High PT group had higher preop PI-LL mismatch (32.1 vs 4.7; P < .001). At last follow-up, 76.5% of patients in the high PT group had continued PI-LL mismatch compared to 34.8% in the low PT group (P < .006). There was a difference between groups in terms of postop changes of PT (-3.9 vs 1.9), LL (8.7 vs 0.5), and PI-LL (-9.5 vs 0.1). Postoperatively, HRQOL data (Oswestry Disability Index and Visual Analog Scale) were significantly improved in both groups (P < .001)., Conclusion: Adult deformity patients with high preoperative PT treated with minimally invasive surgical techniques had less radiographic success but equivalent clinical outcomes as patients with low PT.

Background: The length of construct can potentially influence perioperative risks in adult spinal deformity (ASD) surgery. A head-to-head comparison between open and minimally invasive surgery (MIS) techniques for treatment of ASD has yet to be performed., Objective: To examine the impact of MIS approaches on construct length and clinical outcomes in comparison to traditional open approaches when treating similar ASD profiles., Methods: Two multicenter databases for ASD, 1 involving MIS procedures and the other open procedures, were propensity matched for clinical and radiographic parameters in this observational study. Inclusion criteria were ASD and minimum 2-year follow-up. Independent t -test and chi-square test were used to evaluate and compare outcomes., Results: A total of 1215 patients were identified, with 84 patients matched in each group. Statistical significance was found for mean levels fused (4.8 for circumferential MIS [cMIS] and 10.1 for open), mean interbody fusion levels (3.6 cMIS and 2.4 open), blood loss (estimated blood loss 488 mL cMIS and 1762 mL open), and hospital length of stay (6.7 days cMIS and 9.7 days open). There was no significant difference in preoperative radiographic parameters or postoperative clinical outcomes (Owestry Disability Index and visual analog scale) between groups. There was a significant difference in postoperative lumbar lordosis (43.3° cMIS and 49.8° open) and pelvic incidence-lumbar lordosis correction (10.6° cMIS and 5.2° open) in the open group. There was no significant difference in reoperation rate between the 2 groups., Conclusion: MIS techniques for ASD may reduce construct length, reoperation rates, blood loss, and length of stay without affecting clinical and radiographic outcomes when compared to a similar group of patients treated with open techniques., (Copyright © 2017 by the Congress of Neurological Surgeons)

Background: Proximal junctional kyphosis (PJK) is a known complication after spinal deformity surgery. One potential cause is disruption of posterior muscular tension band during pedicle screw placement., Objective: To investigate the effect of minimally invasive surgery (MIS) on PJK., Methods: A multicenter database of patients who underwent deformity surgery was propensity matched for pelvic incidence (PI) to lumbar lordosis (LL) mismatch and change in LL. Radiographic PJK was defined as proximal junctional angle >10°. Sixty-eight patients made up the circumferential MIS (cMIS) group, and 68 were in the hybrid (HYB) surgery group (open screw placement)., Results: Preoperatively, there was no difference in age, body mass index, PI-LL mismatch, or sagittal vertical axis. The mean number of levels treated posteriorly was 4.7 for cMIS and 8.2 for HYB (P < .001). Both had improved LL and PI-LL mismatch postoperatively. Sagittal vertical axis remained physiological for the cMIS and HYB groups. Oswestry Disability Index scores were significantly improved in both groups. Radiographic PJK developed in 31.3% of the cMIS and 52.9% of the HYB group (P = .01). Reoperation for PJK was 4.5% for the cMIS and 10.3% for the HYB group (P = .20). Subgroup analysis for patients undergoing similar levels of posterior instrumentation in the cMIS and HYB groups found a PJK rate of 48.1% and 53.8% (P = .68) and a reoperation rate of 11.1% and 19.2%, respectively (P = .41). Mean follow-up was 32.8 months., Conclusion: Overall rates of radiographic PJK and reoperation for PJK were not significantly decreased with MIS pedicle screw placement. However, a larger comparative study is needed to confirm that MIS pedicle screw placement does not affect PJK.

Background: Defensive medicine is prevalent among US neurosurgeons due to the high risk of malpractice claims. This study provides national estimates of US neurosurgeons' defensive behaviors and perceptions., Objective: To examine the relationship of defensive medicine-both "assurance" behaviors and "avoidance" behaviors-to the liability environment., Methods: A 51-question online survey was sent to 3344 US neurosurgeon members of the American Board of Neurological Surgeons (ABNS). The survey was anonymous and conducted over 6 weeks in the spring of 2011. The previously validated questionnaire contained questions on neurosurgeon, patient, and practice characteristics; perceptions of the liability environment; and defensive-medicine behaviors. Bivariate and multivariate analyses examined the state liability risk environment as a predictor of a neurosurgeon's likelihood of practicing defensive medicine., Results: A total of 1026 neurosurgeons completed the survey (31% response rate). Neurosurgeons' perceptions of their state's liability environment generally corresponded well to more objective measures of state-level liability risk because 83% of respondents correctly identified that they were practicing in a high-risk environment. When controlling for surgeon experience, income, high-risk patient load, liability history, and type of patient insurance, neurosurgeons were 50% more likely to practice defensive medicine in high-risk states compared with low-risk-risk states (odds ratio: 1.5, P<.05)., Conclusion: Both avoidance and assurance behaviors are prevalent among US neurosurgeons and are correlated with subjective and objective measures of state-level liability risk. Defensive medicine practices do not align with patient-centered care and may contribute to increased inefficiency in an already taxed health care system.

Objective: Thrombolysis has been demonstrated to improve revascularization and outcome in patients with acute ischemic stroke. Many centers now apply thrombolytic therapy locally via intra-arterial infusion. One therapeutic benefit is the ability to cross soft clots with a guidewire and to perform mechanical thrombolysis. In some instances, reopened arteries reocclude as a result of either thrombosis or vasospasm. We report the use of balloon angioplasty during thrombolysis for acute stroke., Methods: From June 1995 through June 1999, 49 patients underwent intra-arterial therapy for acute stroke. In this group, nine patients (seven men and two women) were treated with balloon angioplasty after inadequate recanalization with thrombolytic infusion. The mean age of these patients was 67.9 years. Nine matched control patients who underwent thrombolysis alone without angioplasty were chosen for comparison., Results: In the group of nine patients who had angioplasty, the mean National Institutes of Health Stroke Scale score at presentation was 21.8 +/- 5.4. Four patients had residual distal occlusion after angioplasty, and one patient had a hemorrhagic conversion. Of the five patients in which recanalization was successful, none had reocclusion of the balloon-dilated vessel. The mean score at 30 days for the five survivors was 12.6 +/- 14.9, for an improvement of 7.0 +/- 14.2. Among the nine control patients, the mean score at presentation was 20.3 +/- 5.2; the mean score at 30 days for the five survivors was 19.4 +/- 7.7, for an improvement of 4.2 +/- 7.8., Conclusion: In our experience, balloon angioplasty is a safe, effective adjuvant therapy in patients who are resistant to intra-arterial thrombolysis. The use of balloon angioplasty may prevent reocclusion in a stenotic artery and permit distal infusion of thrombolytic agents.

Objective: Eptifibatide, a competitive platelet glycoprotein IIb-IIIa receptor inhibitor with high selectivity and a short half-life, has been demonstrated to reduce the risk of ischemic events associated with coronary interventions. However, its role in neurointerventional procedures needs to be analyzed. We report the results of an open-label Phase I study to evaluate the safety of the use of eptifibatide during carotid angioplasty and stent placement., Methods: Each study patient received eptifibatide administered intravenously as a 135-microg/kg single-dose bolus, then a 0.5-microg/kg/min infusion for 20 to 24 hours during carotid angioplasty and stent placement. The primary efficacy end point was the 30-day composite occurrence of death, cerebral infarction, transient ischemic attack, and unplanned or urgent surgical intervention, thrombolysis, or subsequent percutaneous revascularization. The primary safety end point was bleeding. Bleeding complications were classified as major (hemoglobin decrease >5 g/dl), minor (hemoglobin decrease 3-5 g/dl), or insignificant., Results: Ten patients (mean age, 73 yr; four men) were treated by use of the study protocol. One patient developed a minor stroke postprocedurally (National Institutes of Health Stroke Scale score of 21 at 24 h that improved to 1 at 7 d). Three patients underwent scheduled coronary artery bypass graft surgery 4 to 12 days after undergoing carotid angioplasty and stent placement. At 1-month follow-up, no new ischemic events were observed. Major or minor bleeding was not observed in any patient. Insignificant bleeding was observed in two patients., Conclusion: The use of eptifibatide as an adjunct to carotid angioplasty and stent placement seems to be safe. Further studies are required to analyze the effectiveness and role of eptifibatide in neurointerventional procedures.

The intervertebral disc is a complex anatomic and biochemical structure. It is composed primarily of fibrocytes and chondrocytes that are anatomically segregated in an elaborate avascular macromolecular matrix of collagen and proteoglycans. Degenerative processes associated with aging and trauma result in morphological and molecular changes to the disc. Morphological changes are observed as dehydration, fissuring, and tearing of the nucleus, annulus and endplates. On the molecular level, degenerative changes include decreased diffusion, decreased cell viability, decreased proteoglycan synthesis, and alteration in collagen distribution. The role of inflammatory mediators in these processes, and the potential use of growth factors to delay or reverse the degenerative cascade, is poorly understood. However, these areas are under active investigation, the results of which may soon contribute significantly to our understanding of degenerative disc disease.

Objective: Urokinase has been conventionally used for intraarterial thrombolysis in acute ischemic stroke. Recently, due to the withdrawal of urokinase from the market, attention has been focused on recombinant tissue plasminogen activator (r-tPA) for intraarterial administration. Data is limited regarding the intraarterial dose, efficacy, and safety profile of this agent., Methods: We prospectively studied 8 consecutive patients with acute ischemic stroke who were referred for intraarterial lysis. Each patient was considered by the treating neurologist to be a poor candidate for intravenous therapy. We administered a maximum total dose of 40 mg of r-tPA intraarterially via superselective catheterization. Angiograms were obtained after each 10 mg of r-tPA, and responses were graded using modified Thrombolysis in Myocardial Infarction (TIMI) criteria for perfusion and degree of thrombus., Results: Initial National Institutes of Health Stroke Scale (NIHSS) scores ranged from 16 to 21. Intervals from presentation to treatment initiation ranged from 1 to 8 hours. After administration of r-tPA, neurological improvement (decrease in NIHSS score > or =2) was observed in 4 patients. Mean perfusion grade improved from a pretreatment score of 0 with increasing doses of r-tPA to 1.1 +/- 1.0 with 10 mg, 1.5 +/- 1.4 with 20 mg, 2.0 +/- 0.8 with 30 mg, and 2.7 +/- 1.0 with 40 mg. Mean thrombus degree decreased from a pretreatment score of 4 with increasing doses of r-tPA to 2.8 +/- 1.2 after 10 mg, 2.6 +/- 1.4 after 20 mg, 1.9 +/- 1.5 after 30 mg, and 1.4 +/- 1.5 after 40 mg. Asymptomatic intraparenchymal hemorrhage was observed on CT scan in 2 patients at 24 hours., Conclusion: Our study suggests that intraarterial r-tPA in doses up to 40 mg is relatively safe. The dose appears to facilitate the recanalization process by lysis of local thrombus and improvement in distal flow.

Objective: Abciximab, a platelet glycoprotein IIb/IIIa receptor inhibitor, has been shown to reduce the risk of ischemic events associated with coronary intervention. However, its role in neurointerventional procedures needs to be defined. We prospectively evaluated our initial experience with the use of abciximab in a series of high-risk patients undergoing carotid, basilar, or vertebral artery angioplasty., Methods: Patients were given an intravenous abciximab bolus (0.25 mg/kg), followed by infusion (10 microg/min) for a period ranging from 12 to 24 hours, as an adjunct to angioplasty in 20 procedures (19 patients). These patients were considered to be at high risk for thromboembolic events because of recent ischemic symptoms and/or complex lesion morphology. Before, immediately after, and 24 hours after the procedure, each patient was evaluated by a neurologist for the presence of new neurological deficits. Any bleeding or other complications during hospitalization were also recorded. Bleeding was defined as major (hemoglobin decrease >5 g/dl), minor (hemoglobin decrease 3-5 g/dl), or insignificant., Results: Angioplasty was performed in the internal carotid artery (n = 13), vertebral artery (n = 4), or basilar artery (n = 2). Stents were placed across 13 lesions. In one patient, angioplasty could not be performed owing to technical difficulties; however, abciximab was administered because of extensive lesion manipulation. Intraprocedural heparin was given in 19 procedures (35-86 U/kg intravenously) and partially reversed in 6 procedures. Low-dose intra-arterial thrombolytic agents were administered in seven patients before the lesion was crossed. Two patients experienced transient neurological deficits either during (n = 1) or immediately after (n = 1) the procedure. Another patient had complete occlusion of the right vertebral artery after angioplasty with complete recanalization after 24 hours of abciximab infusion. Major or minor bleeding was not observed in any patient. Insignificant bleeding was observed in eight patients. Thrombocytopenia was observed in one patient who received concomitant administration of intravenous heparin and abciximab infusion., Conclusion: We observed a low frequency of neurological events in high-risk patients undergoing angioplasty with or without stent placement. Abciximab seems to be a relatively safe adjunct for carotid or vertebrobasilar endovascular intervention either alone or in combination with low-dose thrombolytics. Partial reversal of intraprocedural heparin should be considered to reduce the risk of postprocedural bleeding.

Objective: We report the technique of transradial vertebral artery stenting for two patients in whom severe supra-aortic ectasia prevented ready access to the right vertebral artery origin., Methods: An Allen test was performed to verify ulnar artery collateral flow in the hand. After the administration of local anesthesia, a 6-French sheath was introduced into the radial artery. To allay induced spasm, a mixture of heparin (5000 IU/ml), verapamil (2.5 mg), nitroglycerine (400 microg/ml, 0.25 ml), and lidocaine (2%, 1.0 ml) was infused through the introducer sheath. A microguidewire was positioned across the vertebral artery lesion, followed by placement of a balloon-expandable stent., Results: Postdeployment angiography revealed improved vertebrobasilar system flow. There were no complications related to the radial artery. The patients tolerated the procedure without difficulty and were immediately ambulatory., Conclusion: This novel approach should be considered for endovascular procedures for which access to the vertebral artery origin via the femoral approach is limited.

Objective: The development of low profile, navigable stents has expanded the range of intracranial neuroendovascular procedures. We report a unique case of endovascular stent placement to trap a partially extruded Guglielmi detachable coil (GDC) during treatment of an internal carotid artery (ICA) cavernous segment aneurysm., Methods: A 49-year-old woman presented for endovascular coiling of a left superior hypophyseal artery aneurysm. Previously, a contralateral mirror lesion had been treated by stent-assisted coiling. Heparin was administered to maintain an activated coagulation time of greater than 250 seconds, and a guide catheter was placed in the cervical ICA. A microcatheter was advanced into the aneurysm over a microguidewire. A GDC-10, 3-dimension, 6 x 20-mm coil was placed within the aneurysm, forming a stable basket. Three additional GDCs were placed with near-complete obliteration of the aneurysm. Attempted placement of a fifth coil caused partial prolapse of a previously placed coil into the cavernous ICA. We decided to place a stent rather than to snare the extruded coil because the extruded coil was integral to the aneurysm coil mass. A 3.5x8-mm balloon-expandable stent was placed across the aneurysm orifice, trapping the extruded coil between the stent and ICA., Results: Digital subtraction angiography documented patency of the ICA lumen. The patient remains neurologically intact and awaits 3-month follow-up cerebral angiography., Conclusion: Trapping of an extruded intraaneurysmal coil via stent placement obviated the need for coil removal and avoided the risk of coil mass manipulation. The use of a stent to displace extruded coils and reconstitute a "normal" lumen is an excellent addition to our endovascular armamentarium.

Objective and Importance: Atherosclerotic occlusive disease of the intracranial vasculature is associated with increased risk of systemic vascular occlusive disease and stroke. Therapeutic options have included anticoagulation therapy, antiplatelet therapy, or, in a limited number of patients, extracranial-intracranial vascular bypass procedures. We report a patient who had improved cerebral perfusion with silent watershed zone infarctions after endovascular stenting of a severe petrous segment carotid stenosis., Clinical Presentation: A 73-year-old man with severe coronary artery disease and unstable angina was referred for treatment of a 90% right petrous carotid artery stenosis before coronary artery bypass grafting. A brain single-photon emission computed tomographic scan using 99mTc-bicisate revealed diminished perfusion throughout the right internal carotid artery territory, particularly in posterior watershed zones., Technique: The patient underwent transfemoral placement of a 7-French introducer sheath, followed by a 7-French guide catheter. Urokinase (225,000 U) was infused through a microcatheter placed proximal to the lesion. No changes were noted in lesion morphology after this infusion. A microguidewire was navigated across the lesion. Subsequent balloon angioplasty with a coronary artery balloon was performed twice, followed by placement of a 4- x 12-mm coronary stent., Conclusion: Selective internal carotid artery angiography after stenting revealed markedly improved flow. A brain 99mTc-bicisate single-photon emission computed tomographic scan performed within 24 hours of stent placement, revealed significantly improved perfusion within the right internal carotid artery territory. Two perfusion voids suggestive of embolic stroke were noted; both were clinically silent. The patient had uncomplicated coronary artery bypass grafting 72 hours later. Five months postoperatively, he remains at home, living independently and with intact neurological function. Intracranial stenting for severe atherosclerotic stenosis is technically possible. However, its ultimate clinical role remains to be determined.

Objective and Importance: Symptomatic basilar artery stenosis has a poor prognosis. Treatment options are limited. Surgical bypasses are technically demanding and of no proven benefit. Percutaneous angioplasty is associated with a significant complication rate, because of intraplaque dissection, restenosis secondary to vessel recoil, and embolic phenomena. A new generation of intravascular stents that are flexible enough to navigate the tortuosities of the vertebral artery may provide a new therapeutic approach. We report a case of basilar artery stenosis that was treated using stent-assisted angioplasty., Clinical Presentation: A 56-year-old woman experienced a vertebrobasilar ischemic stroke, from which she recovered. Magnetic resonance angiography revealed severe proximal basilar artery stenosis. Brain Neurolite-single-photon emission computed tomographic scans revealed significantly decreased perfusion of the brainstem. Endovascular intra-arterial pressure measurements revealed a 35-mm Hg gradient across the lesion., Intervention: The patient underwent uncomplicated angioplasty and stenting of the proximal basilar artery, with excellent angiographic results., Conclusion: The availability of new flexible intravascular stents, allowing access to tortuous proximal intracranial vessels, provides a new therapeutic approach for patients with basilar artery stenosis. Long-term follow-up monitoring is required to assess the durability of this approach.

Objective: To evaluate the efficacy of anterior surgery for the treatment of cervical spondylotic myelopathy, we have reviewed our experience with anterior cervical corpectomy (ACC) at the University of Florida, specifically analyzing neurological outcomes and complications. These results have been compared with historical control subjects receiving laminectomy or "no treatment.", Methods: Between 1982 and 1992, 93 ACC operations were performed for the primary diagnosis of cervical spondylotic myelopathy. This consecutive series of patients was reviewed retrospectively. Age, gender, pre- and postoperative myelopathy severity, number of levels decompressed, and neurological complications were assessed. Myelopathy severity was graded using the Nurick myelopathy grading system. The average follow-up period was 39 months (range, 2-137 mo)., Results: Symptomatic improvement was achieved for 92% of patients (F = 28.9, df = 2172, P < 0.001). Nurick scores reflected improvement for 86% of patients, with the conditions of 13% remaining unchanged and only one patient showing worsening. Preoperative myelopathy severity was weakly correlated with age (P < 0.05) but was not correlated with gender or number of levels decompressed. Similarly, postoperative myelopathy severity was not significantly correlated with age, gender, preoperative myelopathy severity, or number of levels decompressed. ACC-treated patients showed an average improvement of 1.24 points on the Nurick scale, compared with an improvement of 0.07 points for patients treated with laminectomy (P < 0.001) and a deterioration of 0.23 points for patients undergoing conservative treatment (P < 0.001). Complications were slightly more likely to occur in older patients (P < 0.05). The number of levels decompressed was not significantly correlated with complications. Only one permanent neurological complication was seen in this series of patients., Conclusion: We conclude that ACC is a safe and effective treatment for cervical spondylotic myelopathy. In an average of 39 months, ACC showed improved results in terms of myelopathy scores, compared with historical control subjects receiving either no treatment or laminectomy. Age, gender, preoperative myelopathy severity, and extent of disease were not negative predictors of clinical outcomes.

Intraoperative ultrasound can aid the biopsy of deep intracranial lesions. It is, perhaps, less clear whether ultrasound could be useful in functional neurosurgery, where the target is not abnormal in echogenicity. As an example, we chose to investigate in a dog model the periventricular gray target, which is frequently the choice for the placement of electrodes to control intractable pain. Autopsies showed the placement of our electrodes with less than 1 mm of error in four of five brains and a 1.5-mm error in the fifth brain. The largest error was seen to occur on the video screen and was due to our failure to tighten the guide properly. The potential advantages of this technique over conventional stereotaxis include the avoidance of: ventricular catheterization, the injection of contrast agent into the ventricles, the necessity for a stereotactic frame, and multiple x-ray exposures. Also, with real time scanning the surgeon has instant visual confirmation of electrode placement and can observe quickly any significant hematoma formation.

A case of infection of the superior sagittal sinus with Petriellidium boydii is reported. This relatively common fungal pathogen rarely invades the central nervous system. Immunological compromise and poor personal hygiene seem to be common attributes shared by this patient and the 4 previous patients reported to have suffered invasion of the central nervous system by this organism. This report is unique in that it is the first demonstrating apparent hematogenous dissemination of this organism to the central nervous system.