The New England Neurosurgical Society: growth and evolution over 70 years

The New England Neurosurgical Society (NENS) was founded in 1951 under the leadership of its first President (Dr. William Beecher Scoville) and Secretary-Treasurer (Dr. Henry Thomas Ballantine). The purpose of creating the NENS was to unite local neurosurgeons in the New England area; it was one of the first regional neurosurgical societies in America. Although regional neurosurgical societies are important supplements to national organizations, they have often been overshadowed in the available literature. Now in its 70th year, the NENS continues to serve as a platform to represent the needs of New England neurosurgeons, foster connections and networks with colleagues, and provide research and educational opportunities for trainees. Additionally, regional societies enable discussion of issues uniquely relevant to the region, improve referral patterns, and allow for easier attendance with geographic proximity. In this paper, the authors describe the history of the NENS and provide a roadmap for its future. The first section portrays the founders who led the first meetings and establishment of the NENS. The second section describes the early years of the NENS and profiles key leaders. The third section discusses subsequent neurosurgeons who steered the NENS and partnerships with other societies. In the fourth section, the modern era of the NENS and its current activities are highlighted.

Atlantoaxial Spondyloptosis with Type II Odontoid Fractures: A Report of 2 Cases

CASE

Two patients with delayed presentations of neck pain and fixed kyphotic deformity after trauma were found to have atlantoaxial spondyloptosis (AAS) with type II dens fractures. Owing to the rarity of AAS, outcomes and optimal treatment are not well understood. In both cases, closed reduction was achieved with a dynamic overhead traction setup, followed by posterior surgical stabilization with C1-2 screw fixation.

CONCLUSION

Closed reduction remains a challenge because of the marked deformity of interlocking C1-C2 joints. However, patients with chronic fixed atlantoaxial dislocation due to odontoid fractures can be safely managed with closed reduction and fusion of C1-C2.

LEVEL OF EVIDENCE

Level V.

Telemedicine and the right to health: A neurosurgical perspective

Neurosurgical task force is limited and unevenly distributed. Telemedicine has become increasingly popular, and could help neurosurgical centers meet patient right to care. This scoping review aims to evaluate the impact and feasibility of telemedicine on the right to neurosurgical care, using the AAAQ toolbox. The AAAQ toolbox consists of Availability, Accessibility, Acceptability and Quality. Neurosurgical availability is limited by the number of neurosurgeons, but by using task shifting and -sharing via telemedicine, the number of patients receiving neurosurgical care could increase without increasing the number of neurosurgeons. Telemedicine can improve geographic accessibility to neurosurgical care, but may also introduce technological literacy barriers. Acceptability of telemedicine is a double-edged sword; while a useful service, telemedicine also creates ethical concerns regarding privacy and confidentiality. Regulations and adaptations for vulnerable patient groups are key considerations for deploying telemedicine. Finally, there is emerging evidence that the quality of remote neurosurgical diagnostics and care can keep high standards. Overall, telemedicine has the potential of taking neurosurgery one step closer to meeting patient right to health, globally.

Fibrous Nonunion of Odontoid Fractures: Is It Safe To Accept Nonoperative Management? A Systematic Review

OBJECTIVE

Nonoperative management of odontoid fractures can result in solid fusion, unstable nonunion, and fibrous nonunion. Odontoid fractures with fibrous nonunion will not demonstrate dynamic instability on imaging studies. However, the safety of accepting this outcome has been debated. We have provided, to the best of our knowledge, the first systematic review of the existing literature to explore the safety of allowing fibrous nonunion as an acceptable outcome for odontoid fractures.

METHODS

The PubMed and Embase databases were searched in January 2022. The outcomes were extracted and categorized according to the mortality, neurologic sequelae, pain, neck disability index, and satisfaction.

RESULTS

Of a total of 700 abstracts screened, the full text of 79 reports was assessed, with 13 studies included. Of the included patients, 141 had had a fibrous nonunion, all described in observational studies. The follow-up ranged from 0.6 to 5.8 years. None of the 141 patients had experienced a neurologic event. One patient had died of trauma-related issues; however, causality was not reported. Most of the studies had reported good to excellent pain scores. Most of the neck disabilities reported had ranged from mild to moderate in severity. However, 1 study of 5 patients had reported severe disability. All the patients reported good or excellent satisfaction.

CONCLUSIONS

The evidence we found supports that it is safe to forgo surgery for carefully selected patients with nonunited odontoid fractures when near-anatomic alignment is present, dynamic instability is lacking on imaging studies, the neurologic examination findings are normal, and the risk of neck injury is low. Further study is needed to define the full natural history of fibrous nonunion of odontoid fractures.

Rare large colloid cyst obstructing the posterior third ventricle: illustrative case

BACKGROUND

Colloid cysts of the posterior third ventricle are exceedingly rare. This location is a high-risk zone for colloid cysts because of potential obstruction of the cerebral aqueduct.

OBSERVATIONS

The authors report a case of a 57-year-old man who presented with a 6-month history of progressive headache, short-term memory loss, visual blurring, and an episode of double vision. Magnetic resonance imaging (MRI) revealed a colloid cyst, 22 mm in diameter, attached to the roof of the posterior third ventricle. The posterior third ventricle was obstructed, but both foramina of Monro were patent. The entirety of the cyst was resected via a right frontal parasagittal, interhemispheric, transventricular approach through the foramen of Monro. It was not contained within the velum interpositum. The patient did not experience any postoperative deficits.

LESSONS

This case supports the theoretical evidence that colloid cysts in the posterior zone of the third ventricle pose a risk for obstructive hydrocephalus. This report of a large cyst in a rare location describes a unique lesion and provides the first published MRI description.

How to Transect the C2 Root for C1 Lateral Mass Screw Placement: Case Series and Review of an Underappreciated Variable in Outcome

BACKGROUND

The techniques for atlantoaxial arthrodesis have been modified over the years, and placing C1 lateral mass screws is a modern approach. C2 neuropathy is a complication of concern; however, sacrifice of the C2 nerve is an accepted and often favored adjunct. The impact of the technique for cutting the C2 nerve is not adequately addressed in the literature. The aim of this study was to evaluate the clinical outcomes from a series of roots sacrificed during C1-2 fusion with attention to the C2 transection method.

METHODS

Clinical data were collected from trauma patients who underwent C1 screw fixation for atlantoaxial fusion. Chart review was performed and outcome assessed through telephone surveys to patients who were at least 6 months postoperative. Quality of life, C2 nerve function, neck pain, and head pain were assessed.

RESULTS

Sixty-six roots were divided in 35 patients. There were no cases of occipital neuralgia at routine 3-month follow-up. Delayed telephone surveys were completed in 17 patients and exposed 4 cases of severe head/neck pain but none consistent with occipital neuralgia.

CONCLUSIONS

C2 neuralgia is rare when sharply dividing the C2 root with the aid of bipolar electrocautery at the midportion of the ganglion where it overlies the C1-2 joint. A literature review suggests the impact of the root sacrifice method is an underappreciated modifiable factor in outcome. In future reports, description of the root transection technique is imperative and trials comparing ganglionectomy versus transection proximal to the ganglion or through the ganglion should be considered.

The relationship between surgical site drains and reoperation for wound-related complications following posterior cervical spine surgery: a multicenter retrospective study

OBJECTIVE

Use of surgical site drains following posterior cervical spine surgery is variable, and its impact on outcomes remains controversial. Studies of drain use in the lumbar spine have suggested that drains are not associated with reduction of reoperations for wound infection or hematoma. There is a paucity of studies examining this relationship in the cervical spine, where hematomas and infections can have severe consequences. This study aims to examine the relationship between surgical site drains and reoperation for wound-related complications following posterior cervical spine surgery.

METHODS

This study is a multicenter retrospective review of 1799 consecutive patients who underwent posterior cervical decompression with instrumentation at 4 tertiary care centers between 2004 and 2016. Demographic and perioperative data were analyzed for associations with drain placement and return to the operating room.

RESULTS

Of 1799 patients, 1180 (65.6%) had a drain placed. Multivariate logistic regression analysis identified history of diabetes (OR 1.37, p = 0.03) and total number of levels operated (OR 1.32, p < 0.001) as independent predictors of drain placement. Rates of reoperation for any surgical site complication were not different between the drain and no-drain groups (4.07% vs 3.88%, p = 0.85). Similarly, rates of reoperation for surgical site infection (1.61% vs 2.58%, p = 0.16) and hematoma (0.68% vs 0.48%, p = 0.62) were not different between the drain and no-drain groups. However, after adjusting for history of diabetes and the number of operative levels, patients with drains had significantly lower odds of returning to the operating room for surgical site infection (OR 0.48, p = 0.04) but not for hematoma (OR 1.22, p = 0.77).

CONCLUSIONS

This large study characterizes current practice patterns in the utilization of surgical site drains during posterior cervical decompression and instrumentation. Patients with drains placed did not have lower odds of returning to the operating room for postoperative hematoma. However, the authors’ data suggest that patients with drains may be less likely to return to the operating room for surgical site infection, although the absolute number of infections in the entire population was small, limiting the analysis.

A protocol for postoperative admission of elective craniotomy patients to a non-ICU or step-down setting

OBJECTIVE Selecting the appropriate patients undergoing craniotomy who can safely forgo postoperative intensive care unit (ICU) monitoring remains a source of debate. Through a multidisciplinary work group, the authors redefined their institutional care process for postoperative monitoring of patients undergoing elective craniotomy to include transfer from the postanesthesia care unit (PACU) to the neurosurgical floor. The hypothesis was that an appropriately selected group of patients undergoing craniotomy could be safely managed outside the ICU in the postoperative period. METHODS The work group developed and implemented a protocol for transfer of patients to the neurosurgical floor after 4-hour recovery in the PACU following elective craniotomy for supratentorial tumor. Criteria included hemodynamically stable adults without significant new postoperative neurological impairment. Data were prospectively collected including patient demographics, clinical characteristics, surgical details, postoperative complications, and events surrounding transfer to a higher level of care. RESULTS Of the first 200 consecutive patients admitted to the floor, 5 underwent escalation of care in the first 48 hours. Three of these escalations were for agitation, 1 for seizure, and 1 for neurological change. Ninety-eight percent of patients meeting criteria for transfer to the floor were managed without incident. No patient experienced a major complication or any permanent morbidity or mortality following this care pathway. CONCLUSIONS Care of patients undergoing uneventful elective supratentorial craniotomy for tumor on a neurosurgical floor after 4 hours of PACU monitoring appears to be a safe practice in this patient population. This tailored practice safely optimized hospital resources, is financially responsible, and is a strong tool for improving health care value.

Appraisal of the Quality of Neurosurgery Clinical Practice Guidelines

OBJECTIVE

The rate of neurosurgery guidelines publications was compared over time with all other specialties. Neurosurgical guidelines and quality of supporting evidence were then analyzed and compared by subspecialty.

METHODS

The authors first performed a PubMed search for "Neurosurgery" and "Guidelines." This was then compared against searches performed for each specialty of the American Board of Medical Specialties. The second analysis was an inventory of all neurosurgery guidelines published by the Agency for Healthcare Research and Quality Guidelines clearinghouse. All Class I evidence and Level 1 recommendations were compared for different subspecialty topics.

RESULTS

When examined from 1970-2010, the rate of increase in publication of neurosurgery guidelines was about one third of all specialties combined (P < 0.0001). However, when only looking at the past 5 years the publication rate of neurosurgery guidelines has converged upon that for all specialties. The second analysis identified 49 published guidelines for assessment. There were 2733 studies cited as supporting evidence, with only 243 of these papers considered the highest class of evidence (8.9%). These papers were used to generate 697 recommendations, of which 170 (24.4%) were considered "Level 1" recommendations.

CONCLUSION

Although initially lagging, the publication of neurosurgical guidelines has recently increased at a rate comparable with that of other specialties. However, the quality of the evidence cited consists of a relatively low number of high-quality studies from which guidelines are created. Wider implications of this must be considered when defining and measuring quality of clinical performance in neurosurgery.

Survival following Ommaya reservoir placement for neoplastic meningitis

The objective of this study was to evaluate the outcomes of patients with neoplastic meningitis (NM) following Ommaya reservoir placement in order to determine whether any patient factors are associated with longer survival. NM is a devastating late manifestation of cancer, and given its dismal prognosis, identifying appropriate patients for Ommaya reservoir placement is difficult. The authors performed a retrospective review of 80 patients who underwent Ommaya reservoir placement at three medical centers from September 2001 through September 2012. The primary outcome was death. Differences in survival were assessed with Kaplan-Meier survival analyses. The Cox proportional hazards and logistic regression modeling were performed to identify factors associated with survival. The primary diagnoses were solid organ, hematologic, and primary central nervous system tumors in 53.8%, 41.3%, and 5%, respectively. The median overall survival was 72.5 days (95% confidence interval 36-122) with 30% expiring within 30 days and only 13.8% surviving more than 1 year. There were no differences in median overall survival between sites (p=0.37) despite differences in time from diagnosis of NM to Ommaya reservoir placement (p<0.001). Diagnosis of hematologic malignancy was inversely associated with death within 90 days (p=0.04; odds ratio 0.34), older age was associated with death within 90 days (p=0.05; odds ratio 1.5, per 10 year increase in age). The prognosis of NM remains poor despite the available treatment with intraventricular chemotherapy. There exists significant variability in treatment algorithms among medical centers and consideration of this variability is crucial when interpreting existing series of Ommaya reservoir use in the treatment of patients with NM.

Lower motor neuron findings after upper motor neuron injury: insights from postoperative supplementary motor area syndrome

Hypertonia and hyperreflexia are classically described responses to upper motor neuron injury. However, acute hypotonia and areflexia with motor deficit are hallmark findings after many central nervous system insults such as acute stroke and spinal shock. Historic theories to explain these contradictory findings have implicated a number of potential mechanisms mostly relying on the loss of descending corticospinal input as the underlying etiology. Unfortunately, these simple descriptions consistently fail to adequately explain the pathophysiology and connectivity leading to acute hyporeflexia and delayed hyperreflexia that result from such insult. This article highlights the common observation of acute hyporeflexia after central nervous system insults and explores the underlying anatomy and physiology. Further, evidence for the underlying connectivity is presented and implicates the dominant role of supraspinal inhibitory influence originating in the supplementary motor area descending through the corticospinal tracts. Unlike traditional explanations, this theory more adequately explains the findings of postoperative supplementary motor area syndrome in which hyporeflexia motor deficit is observed acutely in the face of intact primary motor cortex connections to the spinal cord. Further, the proposed connectivity can be generalized to help explain other insults including stroke, atonic seizures, and spinal shock.

Pneumosinus dilitans and meningioma: a case series and review of the literature

Pneumosinus dilitans (PSD) is enlargement of the sinuses of the skull base and is frequently seen with meningiomas. Identifying PSD on imaging can assist with operative planning and preparation. Meningiomas associated with PSD are not more commonly high grade, and complete resection is frequently possible.

Helmet use and reduction in skull fractures in skiers and snowboarders admitted to the hospital

OBJECT

Helmet use has been associated with fewer hospital visits among injured skiers and snowboarders, but there remains no evidence that helmets alter the intracranial injury patterns. The authors hypothesized that helmet use among skiers and snowboarders reduces the incidence of head injury as defined by findings on head CT scans.

METHODS

The authors performed a retrospective review of head-injured skiers and snowboarders at 2 Level I trauma centers in New England over a 6-year period. The primary outcome of interest was intracranial injury evident on CT scans. Secondary outcomes included the following: need for a neurosurgical procedure, presence of spine injury, need for ICU admission, length of stay, discharge location, and death.

RESULTS

Of the 57 children identified who sustained a head injury while skiing or snowboarding, 33.3% were wearing a helmet at the time of injury. Of the helmeted patients, 5.3% sustained a calvarial fracture compared with 36.8% of the unhelmeted patients (p = 0.009). Although there was a favorable trend, there was no significant difference in the incidence of epidural hematoma, subdural hematoma, intraparenchymal hemorrhage, subarachnoid hemorrhage, or contusion in helmeted and unhelmeted patients. With regard to secondary outcomes, there were no significant differences between the 2 groups in percentage of patients requiring neurosurgical intervention, percentage requiring admission to an ICU, total length of stay, or percentage discharged home. There was no difference in the incidence of cervical spine injury. There was 1 death in an unhelmeted patient, and there were no deaths among helmeted patients.

CONCLUSIONS

Among hospitalized children who sustained a head injury while skiing or snowboarding, a significantly lower number of patients suffered a skull fracture if they were wearing helmets at the time of the injury.

Radiographic assessment of snap-shunt failure: report of 2 cases

Accurate assessment of imaging studies in patients with ventriculoperitoneal shunts can be aided by empirical findings. The authors characterize an objective measurement easily performed on head CT scans with the goal of producing clear evidence of shunt fracture or disconnection in patients with a snap shunt-type system. The authors describe 2 cases of ventriculoperitoneal shunt failure involving a fracture and a disconnection associated with a snap-shunt assembly. In both cases the initial clinical symptoms were not convincing for shunt malfunction, and the interpretation of the CT finding failed to immediately identify the abnormality. As the clinical picture became more convincing for shunt malfunction, each patient subsequently underwent successful shunt revision. The authors reviewed the CT scans of 10 patients with an intact and functioning snap-shunt system to characterize the normal appearance of the snap-shunt connection. On CT scans the distance between the radiopaque portion of the ventricular catheter and the radiopaque portion of the reservoir dome measures an average of 4.72 mm (range 4.6-4.9 mm, 95% CI 4.63-4.81 mm). In the authors' patient with a fractured ventricular catheter, this interval measured 7.8 mm, and in the patient with a disconnection it measured 7.7 mm. In comparison with the range of normal values, a radiolucent interval significantly greater than 4.9 mm should promptly raise concern for a disconnected or fractured shunt in this system. This measurement may prove particularly useful when serial imaging is not readily available.

Laminectomy contributes to cervical spine deformity demonstrated by holographic interferometry

Multiple factors contribute to the pathogenesis of postlaminectomy deformity and instability of the cervical spine. The complex alterations in both static and dynamic biomechanics after laminectomy are incompletely defined. We sought to examine the role of the lamina in compressive load bearing across the vertebral body. Holographic interferometry was used to study the surface deformation of single axially loaded cervical vertebral bodies before and after hemilaminotomy, hemilaminectomy, and experimental acrylic laminar reconstruction. Our results showed that hemilaminotomy did not alter the surface deformation because of axial loading across the cervical vertebral body. However, gross alterations in surface deformation across the cervical vertebral body were consistently observed after hemilaminectomy. Experimental reconstruction of the laminar arch using acrylic restored the deformation pattern to the prelaminectomized baseline. Our results support a role for the lamina and the integrity of the laminar arch in axial load bearing across the cervical vertebral body. The altered axial load bearing may be a significant contributor to postlaminectomy deformity and instability. These findings offer an additional biomechanical advantage to minimal bony intervention for cervical spine pathology.

Percutaneous access to the anterior spinal canal through a cervical disk

We describe a CT-guided percutaneous technique for aspiration of an anterior intraspinal fluid collection through a cervical disk. The approach is identical to that of cervical diskography or percutaneous cervical diskectomy, with intentional placement of the needle tip in the spinal canal. This procedure had no adverse effects and avoided an open operation to exclude spinal cord compression.

Preoperative volume expansion improves tolerance to carotid artery cross-clamping during endarterectomy

OBJECTIVE

The benefit of carotid endarterectomy for carotid artery stenosis relates to both appropriate patient selection and careful surgical technique. Critical to the latter is the ability to afford intraoperative neuroprotection during carotid cross-clamping, although the optimal strategy to assure this protection remains debated. This report describes the impact of adding preoperative colloid volume expansion to a surgical algorithm that includes electroencephalographic (EEG) monitoring and barbiturate-induced burst suppression for EEG lateralization refractory to hypertension.

METHODS

The incidence of ischemic EEG change during carotid cross-clamping was observed. The results of an initial series of patients (n = 45) reported before incorporation of volume expansion were compared with the results of the current series (n = 155) of carotid endarterectomies, which included preoperative volume expansion with 6% hetastarch (500 or 1000 cc).

RESULTS

With preoperative volume expansion, there was a 40% decrease in the incidence of EEG lateralization during carotid cross-clamping (17.4 versus 28.9%, P < 0.05) and a 63% decrease in the EEG lateralization refractory to induced hypertension (5.8 versus 15.6%, P < 0.05). The combined perioperative stroke and death rate was 1.3%.

CONCLUSION

These results support the use of preoperative colloid volume expansion in carotid endarterectomy as a means of increasing the cerebral tolerance to carotid cross-clamping.