James L. West

Biomechanics of open-door laminoplasty with and without preservation of posterior structures.

OBJECTIVE Cervical open-door laminoplasty (ODL) is designed to decompress the spinal cord, maintain motion, and prevent postlaminectomy kyphosis. Many traditional laminoplasty techniques involve disruption of the posterior ligamentous structures, most notably the C7-T1 supraspinous ligament and interspinales muscle complex (intraspinous and supraspinous ligaments [ISLs]). METHODS Eight human cervical cadaveric specimens (C2-T1) were used to investigate the subaxial kinematics following ODL with varying degrees of posterior element disruption. Ligamentous integrity was preserved and specimens were tested utilizing force control in flexion-extension (FE), lateral bending (LB), and axial rotation (AR) in the native state, and following 1) C3-7 ODL, 2) ODL with terminal ISL resection, 3) ODL with C3-7 spinous process resection, and 4) C3-7 laminectomy. Range of motion (ROM) was measured across C2-T1, global, and at the segmental level. RESULTS Compared with ODL, sectioning the terminal ISLs resulted in global ROM increases by 7.9% in FE, 2.4% in LB, and 5.6% in AR (p > 0.05), whereas laminectomy increased global ROM by 36.0% in FE (p = 0.002) and a 26.3% increase in AR ROM (p = 0.01). When considering segmental ROM, resection of the terminal ISLs increased ROM in FE by 36.5% at C2-3 (p = 0.019) and 25.4% at C7-T1 (p > 0.05). Segmental increases following C3-7 spinous process resection averaged less than 3% per level, compared with up to 40% increases in ROM per level after laminectomy. CONCLUSIONS Laminectomy resulted in the greatest increase in global cervical ROM. Resection of the ISLs at C2-3 and C7-T1 increased segmental ROM at these specific levels to a similar extent that laminectomy increased ROM at each cervical level. This segmental ROM may contribute to pain or postprocedural deformity and highlights the importance of the ISLs at the terminal ends of the ODL.

Venous waveform morphological changes associated with treatment of symptomatic venous sinus stenosis

Introduction Venous outflow obstruction is recognized as a contributing factor in a subset of patients with idiopathic intracranial hypertension (IIH). Little is known about venous sinus waveform morphology or how it changes after stenting. Methods Fifteen patients with IIH underwent waveform recording during catheter venography and manometry. Ten patients (Group A) with venous sinus stenosis and pressure gradient ≥7 mm Hg underwent waveform recording during awake venography and during stenting under general anesthesia. Five control IIH patients (Group B) without a gradient underwent awake recording only. Results Group A patients underwent successful stenting with reduction of their gradient from 15.1±6.19 mm Hg to 1.2±0.60 mm Hg. This resulted in an amplitude reduction from 8.3u2009mm Hg to 2.8u2009mm Hg (P=0.02). Qualitative evaluation of the waveform yielded a number of novel findings. In Group A before stenting, the observed waveform progressed from an intracranial pressure (ICP)-dominated to central venous pressure (CVP)-dominated waveform. Stenting abolished the high amplitude waveform and smoothed the transition from the intracranial to central venous measurement points. Group B displayed primarily CVP-influenced waveforms distal and proximal to the transverse-sigmoid junction along with respiratory variability of the waveform, absent in 8/10 Group A patients. General anesthesia appeared to blunt the waveform in 5/10 Group A patients. Conclusion The cerebral venous waveform appears to be influenced by both the ICP and CVP waveforms. As measurement moves proximally, the waveform progressively changes to mirror the CVP waveform. Venous sinus stenosis results in a high amplitude waveform which improves with treatment of the stenosis.

Correlation between angiographic stenosis and physiologic venous sinus outflow obstruction in idiopathic intracranial hypertension

Introduction The relationship between degree of angiographic venous sinus stenosis and the trans-stenosis pressure gradient magnitude in idiopathic intracranial hypertension (IIH) is poorly understood. The present study aimed to assess the utility of angiography, venography, and non-invasive imaging (MRV or CTV) for the diagnosis and characterization of clinically significant VSS. Methods Retrospective analysis of a prospectively collected database was performed to identify patients with medically refractory IIH who were evaluated by angiography and venous manometry for the presence of VSS with associated clinically significant pressure gradient. Angiographic stenosis was measured by two independent raters using novel methodology. Results Thirty-seven patients met inclusion criteria for the study. In total, 70% of patients had clinically significant pressure gradients and were selected for stenting. The optimal percentage stenosis for detection of a significant pressure gradient was 34% stenosis on venous phase arteriography (sensitivity 0.81 and specificity 0.91) and 31% stenosis on venography (0.92 and 0.73). For every 10% increase in stenosis, an approximate increase in pressure gradient of 3.5u2009mmHg is seen. MRV/CTV had a calculated sensitivity of 0.42, and a negative predictive value of 22%. Conclusion The degree of stenosis predictive of a clinically significant pressure gradient (30–35%) in the venous sinuses is considerably lower than the arterial stenosis at which pathologic hemodynamic alterations occur. While highly predictive of a venous pressure gradient when a stenosis is identified, non-invasive imaging does not appear to be a suitable diagnostic evaluation for the purpose of ruling out clinically significant cerebral VSS.

Occipital Condyle Fractures and Concomitant Cervical Spine Fractures: Implications for Management

BACKGROUNDnOccipital condyle fractures (OCFs) have traditionally been described based on anatomic characteristics; however, recent literature has proposed management based on biomechanical stability and neural element compression. The treatment of biomechanically stable fractures varies between observation and cervical immobilization. Before determining the best management approach, an understanding of concomitant cervical spine fractures in the presence of OCFs is important. The primary aim of this pilot study was to determine the rate of occurrence of biomechanically significant cervical spine fractures with OCFs.nnnMETHODSnA retrospective chart review was performed of 13,363 patients presenting to a level 1 trauma center between 2013 and 2017 with a diagnosis of OCF.nnnRESULTSnForty-six patients presented with OCFs, with an average Glasgow Coma Scale score of 12 on presentation and an average Injury Severity Score of 23. The average patient age was 42.1 years, and 4 patients had bilateral OCFs. Approximately 30% of these patients had associated intracranial injuries and 59% had an associated cervical spine injury. The overall rate of associated potentially biomechanically significant cervical spine fracture was 43.5%. Treatment of OCFs included collar immobilization (83%) and observation (17%). The average duration of follow-up was 3.37 months.nnnCONCLUSIONSnThis study characterizes cervical spine fractures that occur concomitantly with OCFs. The results indicate that more than one-half of patients with OCFs do not have biomechanically significant fractures elsewhere in the cervical spine. This subset of patients will be the cohort for a prospective study to assess whether collar immobilization is necessary.

Changes in End-Tidal Carbon Dioxide Partial Pressure Alter Venous Sinus Pressure Measurements in Idiopathic Intracranial Hypertension

BACKGROUNDnIn the diagnosis of venous stenosis associated with idiopathic intracranial hypertension, previous studies have identified significant differences when venous pressures are measured under conscious sedation versus general anesthesia. No previous reports have investigated the effect that respiratory parameters may have on cerebral venous sinus pressure and the associated trans-stenosis pressure gradient.nnnCASE DESCRIPTIONnTwo patients with idiopathic intracranial hypertension were retrospectively identified from a prospective database wherein venous manometry was performed as part of a venous stenting procedure with waveform recording during changes in end-tidal carbon dioxide level (EtCO2). Upon microcatheterization of the superior sagittal sinus after induction of general anesthesia, both patients were noted to have an EtCO2 of 29 mm Hg. After EtCO2 was corrected to 40 mm Hg, repeat venous manometry was conducted, which demonstrated increased SSS venous pressures from 12.6 to 21.1 mm Hg and 18.4 to 30.3 mm Hg in patients 1 and 2, respectively. In addition, the waveform amplitude increased in both patients after EtCO2 correction.nnnCONCLUSIONSnThis series demonstrates that EtCO2 changes have an immediate and pronounced effect on venous sinus pressure measurements with waveform changes that may correlate to increased intracranial pressure. These findings underscore the need to perform measurements of venous sinus pressure gradients under normal awake conditions.

Cerebral Abscess in Young Adult with Hypoplastic Left Heart Syndrome

BACKGROUNDnCerebral abscesses are rare, potentially life-threatening entities that result from local spread or hematogenous dissemination to the brain. Prompt diagnosis and initiation of treatment is key in lowering morbidity and preventing mortality associated with cerebral abscesses. Congenital heart diseases with right-to-left intracardiac shunts can be complicated by brain abscesses via paradoxical embolism of infected microthrombi. Hypoplastic left heart syndrome (HLHS) is a rare congenital heart disease characterized by an underdeveloped left heart that uses intracardiac shunting to achieve adequate systemic circulation. We present the first reported case of a cerebral abscess in a patient with HLHS. The pathophysiology of HLHS and how it predisposes patients to development of cerebral abscesses is discussed.nnnCASE DESCRIPTIONnA 25-year-old male was transferred to our institution complaining of headache, nausea, and vomiting. The patient was not an intravenous (IV) drug user, and serologic testing was negative for human immunodeficiency virus. Magnetic resonance imaging revealed a 2.6-cm left occipital abscess, which was surgically resected without complication, and the patient was treated with IV antibiotics.nnnCONCLUSIONnHLHS is a rare congenital cardiac malformation. The long-term outcome of patients with this condition continues to improve as treatment paradigms evolve. As such, patients with HLHS are living longer, and their potential to develop cerebral abscesses secondary to their unique systemic circulation is increasing with improved life expectancy. Surgeons and physicians should maintain a high index of suspicion for cerebral abscess in the setting of HLHS.

A Comparison of the Existing Wellness Programs in Neurosurgery and Institution Champion's Perspectives

Once the accepted norm during Harvey Cushings time, the mantra of work to the exclusion of family and lifestyle is now recognized as deleterious to overall well-being. A number of neurosurgical residency training programs have implemented wellness programs to enhance the physical, mental, and emotional well-being of trainees and faculty. This manuscript highlights existing organized wellness education within neurosurgery residency programs in order to describe the motivations behind development, structure, and potential implementation strategies, cost of implementation, and identify successes and barriers in the integration process. This manuscript is designed to serve as a how-to guide for other programs who may identify a need in their own trainees and begins the discussion of how to develop wellness, leadership, grit, and resiliency within our future generation of neurosurgeons.

Incidental durotomy in the pediatric spine population

OBJECTIVESpine surgery is less common in children than adults. These surgeries, like all others, are subject to complications such as bleeding, infection, and CSF leak. The rate of incidental durotomy in the pediatric population, and its associated complications, has scarcely been reported in the literature.METHODSThis is a retrospective chart review of all pediatric patients operated on at Wake Forest Baptist Health from 2012 to 2017 who underwent spine surgeries. The authors excluded any procedures with intended durotomy, such as tethered cord release or spinal cord tumor resection.RESULTSFrom 2012 to 2017, 318 pediatric patients underwent surgery for a variety of indications, including adolescent idiopathic scoliosis (51.9%), neuromuscular scoliosis (27.4%), thoracolumbar fracture (2.83%), and other non-fusion-related indications (3.77%). Of these patients, the average age was 14.1 years, and 71.0% were female. There were 6 total incidental durotomies, resulting in an overall incidence of 1.9%. The incidence was 18.5% in revision operations, compared to 0.34% for index surgeries. Comparison of the revision cohort to the durotomy cohort revealed a trend toward increased length of stay, operative time, and blood loss; however, the trends were not statistically significant. The pedicle probe was implicated in 3 cases and the exact cause was not ascertained in the remaining 3 cases. The 3 durotomies caused by pedicle probe were treated with bone wax; 1 was treated with dry Gelfoam application and 2 were treated with primary repair. Only 1 patient had a persistent leak postoperatively that eventually required wound revision.CONCLUSIONSIncidental durotomy is an uncommon occurrence in the pediatric spinal surgery population. The majority occurred during placement of pedicle screws, and they were easily treated with bone wax at the time of surgery. Awareness of the incidence, predisposing factors, and treatment options is important in preventing complications and disability.

Lifting the veil on stroke outcomes: revisiting stroke centers’ transparency through public reporting of metrics

Public reporting of healthcare metrics provides transparency that allows patients and emergency medical providers to make informed decisions about where patients should receive care. Most previous reports about public reporting of health metrics have demonstrated significant improvements in outcome metrics after implementation. However, no mechanism exists, voluntary or otherwise, for the public reporting of outcomes of stroke care. We review the components of public reporting of health outcomes data and its limited history in stroke outcomes. We summarize the literature on public reporting in cardiovascular interventions, particularly percutaneous coronary interventions, as a close corollary to mechanical neurothrombectomy. The benefits, limitations, and controversies associated with reporting of cardiovascular outcomes are reviewed with a focus on the development of risk-avoidant behaviors. This article serves as a primer for discussion of the potential benefits, limitations, and unintended consequences of public reporting of stroke data.

Unexpected early radiographic findings associated with a ruptured blister-like carotid wall aneurysm

A 33-year-old man presented with aneurysmal subarachnoid hemorrhage from a ruptured, blister-type sidewall internal carotid artery (ICA) aneurysm. Balloon-assisted coiling was performed with residual neck. He subsequently developed severe vasospasm requiring intra-arterial therapies on multiple occasions, during which it was noted that despite widespread vasospasm, a focal segment of the ICA at the site of the aneurysm showed no significant spasm, suggesting underlying vessel abnormality. He was discharged without deficit and scheduled for flow diversion given concern over this potentially pathologic segment of vessel. At time of scheduled flow diversion 6 weeks later, a de novo unstable-appearing 6u2009mm stalk-like pseudoaneurysm was identified in this segment. Both aneurysms and the diseased vessel were successfully treated with Pipeline stenting, with excellent clinical and angiographic result. This case highlights the need for close angiographic follow-up when there is a heterogeneous vasospastic response in arterial segments adjacent to a ruptured aneurysm.