bluuebunny/crossref_metadata_2025 huggingface dataset:
Dual responsive neurostimulation implants for epilepsy
Authors: Barbaro Michael F. , Chesney Kelsi , Kramer Daniel R. , Kellis Spencer , Peng Terrance , Blumenfeld Zack , Gogia Angad S. , Lee Morgan B. , Greenwood Janet , Nune George , Kalayjian Laura A. , Heck Christianne N. , Liu Charles Y. , Lee Brian
Published: February 2019

Closed-loop brain-responsive neurostimulation via the RNS System is a treatment option for adults with medically refractory focal epilepsy. Using a novel technique, 2 RNS Systems (2 neurostimulators and 4 leads) were successfully implanted in a single patient with bilateral parietal epileptogenic zones. In patients with multiple epileptogenic zones, this technique allows for additional treatment options. Implantation can be done successfully, without telemetry interference, using proper surgical planning and neurostimulator positioning.

Trajectories for the depth leads were planned using neuronavigation with CT and MR imaging. Stereotactic frames were used for coordinate targeting. Each neurostimulator was positioned with maximal spacing to avoid telemetry interference while minimizing patient discomfort. A separate J-shaped incision was used for each neurostimulator to allow for compartmentalization in case of infection. In order to minimize surgical time and risk of infection, the neurostimulators were implanted in 2 separate surgeries, approximately 3 weeks apart.

The neurostimulators and leads were successfully implanted without adverse surgical outcomes. The patient recovered uneventfully, and the early therapy settings over several months resulted in preliminary decreases in aura and seizure frequency. Stimulation by one of the neurostimulators did not result in stimulation artifacts detected by the contralateral neurostimulator.
Management and outcomes of isolated interhemispheric subdural hematomas associated with falx syndrome
Authors: Tonetti Daniel A. , Ares William J. , Okonkwo David O. , Gardner Paul A.
Published: February 2019

OBJECTIVE

Large interhemispheric subdural hematomas (iSDHs) causing falx syndrome are rare; therefore, a paucity of data exists regarding the outcomes of contemporary management of iSDH. There is a general consensus among neurosurgeons that large iSDHs with neurological deficits represent a particular treatment challenge with generally poor outcomes. Thus, radiological and clinical outcomes of surgical and nonsurgical management for iSDH bear further study, which is the aim of this report.

METHODS

A prospectively collected, single-institution trauma database was searched for patients with isolated traumatic iSDH causing falx syndrome in the period from January 2008 to January 2018. Information on demographic and radiological characteristics, serial neurological examinations, clinical and radiological outcomes, and posttreatment complications was collected and tallied. The authors subsequently dichotomized patients by management strategy to evaluate clinical outcome and 30-day survival.

RESULTS

Twenty-five patients (0.4% of those with intracranial injuries, 0.05% of those with trauma) with iSDH and falx syndrome represented the study cohort. The average age was 73.4 years, and most patients (23 [92%] of 25) were taking anticoagulants or antiplatelet medications. Six patients were managed nonoperatively, and 19 patients underwent craniotomy for iSDH evacuation; of the latter patients, 17 (89.5%) had improvement in or resolution of motor deficits postoperatively. There were no instances of venous infarction, reaccumulation, or infection after evacuation. In total, 9 (36%) of the 25 patients died within 30 days, including 6 (32%) of the 19 who had undergone craniotomy and 3 (50%) of the 6 who had been managed nonoperatively. Patients who died within 30 days were significantly more likely to experience in-hospital neurological deterioration prior to surgery (83% vs 15%, p = 0.0095) and to be comatose prior to surgery (100% vs 23%, p = 0.0031). The median modified Rankin Scale score of surgical patients who survived hospitalization (13 patients) was 1 at a mean follow-up of 22.1 months.

CONCLUSIONS

iSDHs associated with falx syndrome can be evacuated safely and effectively, and prompt surgical evacuation prior to neurological deterioration can improve outcomes. In this study, craniotomy for iSDH evacuation proved to be a low-risk strategy that was associated with generally good outcomes, though appropriately selected patients may fare well without evacuation.
Assessment of lipoprotein-associated phospholipase A2 level and its changes in the early stages as predictors of delayed cerebral ischemia in patients with aneurysmal subarachnoid hemorrhage
Authors: Ding Chen-Yu , Cai Han-Pei , Ge Hong-Liang , Yu Liang-Hong , Lin Yuan-Xiang , Kang De-Zhi
Published: February 2019

OBJECTIVE

The relationship between lipoprotein-associated phospholipase A2 (Lp-PLA2) and various cardiovascular and cerebrovascular diseases is inconsistent. However, the connection between Lp-PLA2 level and delayed cerebral ischemia (DCI) following aneurysmal subarachnoid hemorrhage (aSAH) remains unclear. The objective of this study was to investigate the relationships between the Lp-PLA2 levels in the early stages of aSAH and the occurrence of DCI.

METHODS

The authors evaluated 114 patients with aSAH who were enrolled into a prospective observational cohort study. Serum Lp-PLA2 level at admission (D0), on the first morning (D1), and on the second morning of hospitalization (D2) were determined using commercial enzyme-linked immunosorbent assay kits. The relationship between Lp-PLA2 levels and DCI was analyzed.

RESULTS

Forty-three patients with aSAH (37.72%) experienced DCI. Mean serum Lp-PLA2 level decreased from 183.06 ± 61.36 μg/L at D0 (D0 vs D1, p = 0.303), to 175.32 ± 51.49 μg/L at D1 and 167.24 ± 54.10 μg/L at D2 (D0 vs D2, p = 0.040). The Lp-PLA2 level changes (D0-D1 and D0-D2) were comparable between patients with and without DCI. Multivariate model analysis revealed Lp-PLA2 level (D0) > 200 μg/L was a more significant factor of DCI compared with Lp-PLA2 (D1) and Lp-PLA2 (D2), and was a strong predictor of DCI (odds ratio [OR] 6.24, 95% confidence interval [CI] 2.05–18.94, p = 0.001) after controlling for World Federation of Neurosurgical Societies (WFNS) grade (OR 3.35, 95% CI 1.18–9.51, p = 0.023) and modified Fisher grade (OR 6.07, 95% CI 2.03–18.14, p = 0.001). WFNS grade (area under the curve [AUC] = 0.792), modified Fisher grade (AUC = 0.731), and Lp-PLA2 level (D0; AUC = 0.710) were all strong predictors of DCI. The predictive powers of WFNS grade, modified Fisher grade, and Lp-PLA2 (D0) were comparable (WFNS grade vs Lp-PLA2: p = 0.233; modified Fisher grade vs Lp-PLA2: p = 0.771). The poor-grade patients with Lp-PLA2 (D0) > 200 μg/L had significantly worse DCI survival rate than poor-grade patients with Lp-PLA2 (D0) ≤ 200 μg/L (p < 0.001).

CONCLUSIONS

The serum level of Lp-PLA2 was significantly elevated in patients with DCI, and decreased within the first 2 days after admission. Lp-PLA2 in the early stages of aSAH might be a novel predictive biomarker for the occurrence of DCI.
Impact of frailty on short-term outcomes in patients undergoing transsphenoidal pituitary surgery
Authors: Asemota Anthony O. , Gallia Gary L.
Published: February 2019

OBJECTIVE

Frailty, a state of decreased physiological reserve, has been shown to significantly impact outcomes of surgery. The authors sought to examine the impact of frailty on the short-term outcomes of patients undergoing transsphenoidal pituitary surgery.

METHODS

Weighted data from the 2000–2014 National (Nationwide) Inpatient Sample were studied. Patients diagnosed with pituitary tumors or disorders who had undergone transsphenoidal pituitary surgery were identified. Frailty was determined using the Johns Hopkins Adjusted Clinical Groups (ACG) frailty-defining diagnoses indicator. Standard descriptive techniques and matched propensity score analyses were used to explore the odds ratios of postoperative complications, discharge dispositions, and costs.

RESULTS

A total of 115,317 cases were included in the analysis. Frailty was present in 1.48% of cases. The mean age of frail versus non-frail patients was 57.14 ± 16.96 years (mean ± standard deviation) versus 51.91 ± 15.88 years, respectively (p < 0.001). A greater proportion of frail compared to non-frail patients had an age ≥ 65 years (37.08% vs 24.08%, respectively, p < 0.001). Frail patients were more likely to be black or Hispanic (p < 0.001), possess Medicare or Medicaid insurance (p < 0.001), belong to lower-median-income groups (p < 0.001), and have greater comorbidity (p < 0.001). Results of propensity score–matched multivariate analysis revealed that frail patients were more likely to develop fluid and electrolyte disorders (OR 1.61, 95% CI 1.07–2.43, p = 0.02), intracranial vascular complications (OR 2.73, 95% CI 1.01–7.49, p = 0.04), mental status changes (OR 3.60, 95% CI 1.65–7.82, p < 0.001), and medical complications including pulmonary insufficiency (OR 2.01, 95% CI 1.13–4.05, p = 0.02) and acute kidney failure (OR 4.70, 95% CI 1.88–11.74, p = 0.01). The mortality rate was higher among frail patients (1.46% vs 0.37%, p < 0.001). Frail patients also demonstrated a greater likelihood for nonroutine discharges (p < 0.001), higher mean total charges ($109,614.33 [95% CI $92,756.09–$126,472.50] vs $56,370.35 [95% CI $55,595.72–$57,144.98], p < 0.001), and longer hospitalizations (9.27 days [95% CI 7.79–10.75] vs 4.46 days [95% CI 4.39–4.53], p < 0.001).

CONCLUSIONS

Frailty in patients undergoing transsphenoidal pituitary surgery is associated with worse postoperative outcomes and higher costs, indicating that state’s potential role in routine preoperative risk stratification.
Wilder Penfield and the vascular hypothesis of focal epilepsy
Authors: Leblanc Richard
Published: February 2019

The vascular hypothesis held that posttraumatic epilepsy results from reflex vasoconstriction of cortical arteries around a cerebral scar. Penfield’s initial support and eventual refutation of the vascular hypothesis is the subject of this paper, which is based on a review of his clinical charts, operative and electrocorticographic reports, and brain maps held in the Montreal Neurological Institute archives. Penfield and his collaborators discovered that posttraumatic cortical scars are composed of astro-glial fibers, collagen fibrils, and a neo-vascular plexus that anastomoses with the surrounding cortical arteries. He hypothesized that the contracting scar applied traction to these arteries, which caused epileptic seizures. This was supported by his observations that cortical arteries constrict during an epileptic seizure. Penfield’s subsequent investigations led to the discovery that parasympathetic nerves innervate the intracranial arteries, that experimental vasospasm can produce cortical infarction, and that cerebral blood flow (CBF) is coupled to cerebral metabolism. In fact, Penfield found that CBF increases in the epileptogenic zone around a cortical scar, contrary to what the hypothesis had predicted. Despite this, Penfield’s investigations shed new light on the dynamics of the cerebral circulation that were not fully understood until decades later.
Cavernous sinus aneurysms: risk of growth over time and risk factors
Authors: Vercelli Giovanni , Sorenson Thomas J. , Aljobeh Ahmad Z. , Vine Roanna , Lanzino Giuseppe
Published: February 2019

OBJECTIVE

Cavernous internal carotid artery (ICA) aneurysms are frequently diagnosed incidentally and the benign natural history of these lesions is well known, but there is limited information assessing the risk of growth in untreated patients. The authors sought to assess and analyze risk factors in patients with cavernous ICA aneurysms and compare them to those of patients with intracranial berry aneurysms in other locations.

METHODS

Data from consecutive patients who were diagnosed with a cavernous ICA aneurysm were retrospectively reviewed. The authors evaluated patients for the incidence of cavernous ICA aneurysm growth and rupture. In addition, the authors analyzed risk factors for cavernous ICA aneurysm growth and compared them to risk factors in a population of patients diagnosed with intracranial berry aneurysms in locations other than the cavernous ICA during the same period.

RESULTS

In 194 patients with 208 cavernous ICA aneurysms, the authors found a high risk of aneurysm growth (19.2% per patient-year) in patients with large/giant aneurysms. Size was significantly associated with higher risk of growth. Compared to patients with intracranial berry aneurysms in other locations, patients with cavernous ICA aneurysms were significantly more likely to be female and have a lower incidence of hypertension.

CONCLUSIONS

Aneurysms of the cavernous ICA are benign lesions with a negligible risk of rupture but a definite risk of growth. Aneurysm size was found to be associated with aneurysm growth, which can be associated with new onset of symptoms. Serial follow-up imaging of a cavernous ICA aneurysm might be indicated to monitor for asymptomatic growth, especially in patients with larger lesions.
Third delay in traumatic brain injury: time to management as a predictor of mortality
Authors: Gupta Saksham , Khajanchi Monty , Kumar Vineet , Raykar Nakul P. , Alkire Blake C. , Roy Nobhojit , Park Kee B.
Published: February 2019

OBJECTIVE

Traumatic brain injury (TBI) is a global epidemic with an increasing incidence in low- and middle-income countries (LMICs). The time from arrival at the hospital to receiving appropriate treatment (“third delay”) can vary widely in LMICs, although its association with mortality in TBI remains unknown.

METHODS

A retrospective cohort analysis with multivariable logistic regression was conducted using the Toward Improved Trauma Care Outcomes in India database, which contains data from 4 urban trauma centers in India from 2013–2015.

RESULTS

There were 6278 TBIs included in the cohort. The patients’ median age was 39 years (interquartile range 27–52 years) and 80% of patients were male. The most frequent mechanisms of injury were road traffic accidents (52%) and falls (34%). A majority of cases were transfers from other facilities (79%). In-hospital 30-day mortality was 27%; of patients who died, 21% died within 24 hours of arrival. The median third delay was 10 minutes (interquartile range 0–60 minutes); 34% of cases had moderate third delay (10–60 minutes) and 22% had extended third delay (≥ 61 minutes). Overall 30-day mortality was associated with moderate third delay (OR 1.3, p = 0.001) and extended third delay (OR 1.3, p = 0.001) after adjustment by pertinent covariates. This effect was pronounced for 24-hour mortality: moderate and extended third delays were independently associated with ORs of 3.4 and 3.8, respectively, for 24-hour mortality (both p < 0.001).

CONCLUSIONS

Third delay is associated with early mortality in patients with TBI, and represents a target for process improvement in urban trauma centers.
Factors influencing the presence of hemiparesis in chronic subdural hematoma
Authors: Motiei-Langroudi Rouzbeh , Alterman Ron L. , Stippler Martina , Phan Kevin , Alturki Abdulrahman Y. , Papavassiliou Efstathios , Kasper Ekkehard M. , Arle Jeffrey , Ogilvy Christopher S. , Thomas Ajith J.
Published: February 2019

OBJECTIVE

Chronic subdural hematoma (CSDH) has a variety of clinical presentations, including hemiparesis. Hemiparesis is of the utmost importance because it is one of the major indications for surgical intervention and influences outcome. In the current study, the authors intended to identify factors influencing the presence of hemiparesis in CSDH patients and to determine the threshold value of hematoma thickness and midline shift for development of hemiparesis.

METHODS

The authors retrospectively reviewed 325 patients (266 with unilateral and 59 with bilateral hematomas) with CSDH who underwent surgical evacuation, regardless of presence or absence of hemiparesis.

RESULTS

In univariate analysis, hematoma loculation, age, hematoma maximal thickness, and midline shift were significantly associated with hemiparesis. Moreover, patients with unilateral hematomas had a higher rate of hemiparesis than patients with bilateral hematomas. Sex, trauma history, anticoagulant and antiplatelet drug use, presence of comorbidities, Glasgow Coma Scale score, hematoma density characteristics on CT scan, and hematoma signal intensity on T1- and T2-weighted MRI were not associated with hemiparesis. In multivariate analysis, the presence of loculation and hematoma laterality (unilateral vs bilateral) influenced hemiparesis. For unilateral hematomas, maximal hematoma thickness of 19.8 mm and midline shift of 6.4 mm were associated with a 50% probability of hemiparesis. For bilateral hematomas, 29.0 mm of maximal hematoma thickness and 6.8 mm of shift were associated with a 50% probability of hemiparesis.

CONCLUSIONS

Presence of loculations, unilateral hematomas, older patient age, hematoma maximal thickness, and midline shift were associated with a higher rate of hemiparesis in CSDH patients. Moreover, 19.8 mm of hematoma thickness and 6.4 mm of midline shift were associated with a 50% probability of hemiparesis in patients with unilateral hematomas.
Outcomes after coverage of lenticulostriate vessels by flow diverters: a multicenter experience
Authors: Wagner Kathryn M. , Srinivasan Visish M. , Srivatsan Aditya , Ghali Michael G. Z. , Thomas Ajith J. , Enriquez-Marulanda Alejandro , Alturki Abdulrahman Y. , Ogilvy Christopher S. , Mokin Maxim , Kuhn Anna L. , Puri Ajit , Grandhi Ramesh , Chen Stephen , Johnson Jeremiah , Kan Peter
Published: February 2019

OBJECTIVE

With the increasing use of flow diversion as treatment for intracranial aneurysms, there is a concomitant increased vigilance in monitoring complications. The low porosity of flow diverters is concerning when the origins of vessels are covered, whether large circle of Willis branches or critical perforators. In this study, the authors report their experience with flow diverter coverage of the lenticulostriate vessels and evaluate their safety and outcomes.

METHODS

The authors retrospectively reviewed 5 institutional databases of all flow diversion cases from August 2012 to June 2018. Information regarding patient presentation, aneurysm location, treatment, and outcomes were recorded. Patients who were treated with flow diverters placed in the proximal middle cerebral artery (MCA), proximal anterior cerebral artery, or distal internal carotid artery leading to coverage of the medial and lateral lenticulostriate vessels were included. Clinical outcomes according to the modified Rankin Scale were reviewed. Univariate and multivariate analyses were performed to establish risk factors for lenticulostriate infarct.

RESULTS

Fifty-two patients were included in the analysis. Postprocedure cross-sectional images were available in 30 patients. Two patients experienced transient occlusion of the MCA during the procedure; one was asymptomatic, and the other had a clinical and radiographic ipsilateral internal capsule stroke. Five patients had transient symptoms without radiographic infarct in the lenticulostriate territory. Two patients experienced in-stent thrombosis, leading to clinical MCA infarcts (one in the ipsilateral caudate) after discontinuing antiplatelet therapy. Discontinuation of dual antiplatelet therapy prior to 6 months was the only variable that was significantly correlated with stroke outcome (p < 0.01, OR 0.3, 95% CI 0–0.43), and this significance persisted when controlled for other risk factors, including age, smoking status, and aneurysm location.

CONCLUSIONS

The use and versatility of flow diversion is increasing, and safety data are continuing to accumulate. Here, the authors provide early data on the safety of covering lenticulostriate vessels with flow diverters. The authors concluded that the coverage of these perforators does not routinely lead to clinically significant ischemia when dual antiplatelet therapy is continued for 6 months. Further evaluation is needed in larger cohorts and with imaging follow-up as experience develops in using these devices in more distal circulation.
Effectiveness of staged angioplasty for avoidance of cerebral hyperperfusion syndrome after carotid revascularization
Authors: Hayakawa Mikito , Sugiu Kenji , Yoshimura Shinichi , Hishikawa Tomohito , Yamagami Hiroshi , Fukuda-Doi Mayumi , Sakai Nobuyuki , Iihara Koji , Ogasawara Kuniaki , Oishi Hidenori , Ito Yasushi , Matsumaru Yuji
Published: February 2019

OBJECTIVE

Cerebral hyperperfusion syndrome (CHS) is a serious complication after carotid artery stenting (CAS). Staged angioplasty (SAP)—i.e., angioplasty followed by delayed CAS—has been reported as a potential CHS-avoiding procedure. The purpose of this study was to clarify the effectiveness of SAP in avoiding CHS after carotid revascularization for patients at high risk for this complication.

METHODS

The authors retrospectively studied cases involving patients at high risk for CHS from 44 Japanese centers who were scheduled for SAP, regular CAS, angioplasty, or staged procedures other than SAP between October 2007 and March 2014. They investigated the rate of CHS in the population scheduled for SAP or regular CAS, and for safety analysis, the composite rate of transient ischemic attack (TIA) and ischemic stroke in the population eventually receiving SAP or regular CAS.

RESULTS

Data from a total of 525 patients (532 lesions, mean age 72.5 ± 7.5 years, 74 women ) were analyzed. Scheduled procedures included SAP for 113 lesions and regular CAS for 419 lesions. The rate of CHS was lower in the SAP group than in the regular CAS group (4.4% vs 10.5%, p = 0.047). Multivariate analysis showed that SAP was negatively related to CHS (OR 0.315; 95% CI 0.120–0.828). In the population eventually receiving SAP (102 lesions) or regular CAS (428 lesions), the composite rate of TIA and ischemic stroke was comparable between the SAP group and the regular CAS group (9.8% vs 9.3%).

CONCLUSIONS

SAP may be an effective and safe carotid revascularization procedure to avoid CHS.
Patterns of opioid use in patients with trigeminal neuralgia undergoing neurosurgery
Authors: Yang Andrew I. , McShane Brendan J. , Hitti Frederick L. , Sandhu Sukhmeet K. , Chen H. Isaac , Lee John Y. K.
Published: February 2019

OBJECTIVE

First-line treatment for trigeminal neuralgia (TN) is pharmacological management using antiepileptic drugs (AEDs), e.g., carbamazepine (CBZ) and oxcarbazepine (OCBZ). Surgical intervention has been shown to be an effective and durable treatment for TN that is refractory to medical therapy. Despite the lack of evidence for efficacy in patients with TN, the authors hypothesized that patients with neuropathic facial pain are prescribed opioids at high rates, and that neurosurgical intervention may lead to a reduction in opioid use.

METHODS

This is a retrospective study of patients with facial pain seen by a single neurosurgeon. All patients completed a survey on pain medications, medical comorbidities, prior interventions for facial pain, and a validated pain outcome tool (the Penn Facial Pain Scale). Patients subsequently undergoing neurosurgical intervention completed a survey at the 1-month follow-up in the office, in addition to telephone interviews using a standardized script between 1 and 6 years after intervention. Univariate and multivariate logistic regression were used to predict opioid use.

RESULTS

The study cohort consisted of 309 patients (70% Burchiel type 1 TN [TN1], 18% Burchiel type 2 [TN2], 6% atypical facial pain [AFP], and 6% TN secondary to multiple sclerosis [TN-MS]). At initial presentation, 20% of patients were taking opioids. Of these patients, 55% were receiving concurrent opioid therapy with CBZ/OCBZ, and 84% were receiving concurrent therapy with at least one type of AED. Facial pain diagnosis (for diagnoses other than TN1, odds ratio [OR] 2.5, p = 0.01) and facial pain intensity at its worst (for each unit increase, OR 1.4, p = 0.005) were predictors of opioid use at baseline. Neurosurgical intervention led to a reduction in opioid use to 8% at long-term follow-up (p < 0.01, Fisher’s exact test; n = 154). Diagnosis (for diagnoses other than TN1, OR 4.7, p = 0.002) and postintervention reduction in pain at its worst (for each unit reduction, OR 0.8, p < 10−3) were predictors of opioid use at long-term follow-up. On subgroup analysis, patients with TN1 demonstrated a decrease in opioid use to 5% at long-term follow-up (p < 0.05, Fisher’s exact test), whereas patients with non-TN1 facial pain did not. In the nonsurgical group, there was no statistically significant decrease in opioid use at long-term follow-up (n = 81).

CONCLUSIONS

In spite of its high potential for abuse, opioid use, mostly as an adjunct to AEDs, is prevalent in patients with facial pain. Opportunities to curb opioid use in TN1 include earlier neurosurgical intervention.
Long-term impact of pediatric endoscopic endonasal skull base surgery on midface growth
Authors: Chen Wendy , Gardner Paul A. , Branstetter Barton F. , Liu Shih-Dun , Chang Yue Fang , Snyderman Carl H. , Goldstein Jesse A. , Tyler-Kabara Elizabeth C. , Schuster Lindsay A.
Published: February 2019

OBJECTIVE

Cranial base development plays a large role in anterior and vertical maxillary growth through 7 years of age, and the effect of early endonasal cranial base surgery on midface growth is unknown. The authors present their experience with pediatric endoscopic endonasal surgery (EES) and long-term midface growth.

METHODS

This is a retrospective review of cases where EES was performed from 2000 to 2016. Patients who underwent their first EES of the skull base before age 7 (prior to cranial suture fusion) and had a complete set of pre- and postoperative imaging studies (CT or MRI) with at least 1 year of follow-up were included. A radiologist performed measurements (sella-nasion [S-N] distance and angles between the sella, nasion, and the most concave points of the anterior maxilla [A point] or anterior mandibular synthesis [B point], the SNA, SNB, and ANB angles), which were compared to age- and sex-matched Bolton standards. A Z-score test was used; significance was set at p < 0.05.

RESULTS

The early surgery group had 11 patients, with an average follow-up of 5 years; the late surgery group had 33 patients. Most tumors were benign; 1 patient with a panclival arteriovenous malformation was a significant outlier for all measurements. Comparing the measurements obtained in the early surgery group to Bolton standard norms, the authors found no significant difference in postoperative SNA (p = 0.10), SNB (p = 0.14), or ANB (0.67) angles. The S-N distance was reduced both pre- and postoperatively (SD 1.5, p = 0.01 and p = 0.009). Sex had no significant effect. Compared to patients who had surgery after the age of 7 years, the early surgery group demonstrated no significant difference in pre- to postoperative changes with regard to S-N distance (p = 0.87), SNA angle (p = 0.89), or ANB angle (p = 0.14). Lesion type (craniopharyngioma, angiofibroma, and other types) had no significant effect in either age group.

CONCLUSIONS

Though our cohort of patients with skull base lesions demonstrated some abnormal measurements in the maxillary-mandibular relationship before their operation, their postoperative cephalometrics fell within the normal range and showed no significant difference from those of patients who underwent operations at an older age. Therefore, there appears to be no evidence of impact of endoscopic endonasal skull base surgery on craniofacial development within the growth period studied.
Unintended facet fusions after Dynesys dynamic stabilization in patients with spondylolisthesis
Authors: Fay Li-Yu , Huang Wen-Cheng , Chang Chih-Chang , Chang Hsuan-Kan , Tsai Tzu-Yun , Tu Tsung-Hsi , Wu Ching-Lan , Cheng Henrich , Wu Jau-Ching
Published: February 2019

OBJECTIVE

The pedicle screw–based Dynesys dynamic stabilization (DDS) has reportedly become a surgical option for lumbar spondylosis and spondylolisthesis. However, it is still unclear whether the dynamic construct remains mobile or eventually fuses. The aim of this study was to investigate the incidence of unintended facet arthrodesis after DDS and its association with spondylolisthesis.

METHODS

This retrospective study was designed to review 105 consecutive patients with 1- or 2-level lumbar spondylosis who were treated with DDS surgery. The patients were then divided into 2 groups according to preexisting spondylolisthesis or not. All patients underwent laminectomies, foraminotomies, and DDS. The clinical outcomes were measured using visual analog scale (VAS) scores for back and leg pain, Japanese Orthopaedic Association (JOA) scores, and Oswestry Disability Index (ODI) scores. All medical records, including pre- and postoperative radiographs, CT scans, and MR images, were also reviewed and compared.

RESULTS

A total of 96 patients who completed the postoperative follow-up for more than 30 months were analyzed. The mean age was 64.1 ± 12.9 years, and the mean follow-up duration was 46.3 ± 12.0 months. There were 45 patients in the spondylolisthesis group and 51 patients in the nonspondylolisthesis group. The overall prevalence rate of unintended facet fusion was 52.1% in the series of DDS. Patients with spondylolisthesis were older (67.8 vs 60.8 years, p = 0.007) and had a higher incidence rate of facet arthrodesis (75.6% vs 31.4%, p < 0.001) than patients without spondylolisthesis. Patients who had spondylolisthesis or were older than 65 years were more likely to have facet arthrodesis (OR 6.76 and 4.82, respectively). There were no significant differences in clinical outcomes, including VAS back and leg pain, ODI, and JOA scores between the 2 groups. Furthermore, regardless of whether or not unintended facet arthrodesis occurred, all patients experienced significant improvement (all p < 0.05) in the clinical evaluations.

CONCLUSIONS

During the mean follow-up of almost 4 years, the prevalence of unintended facet arthrodesis was 52.1% in patients who underwent DDS. Although the clinical outcomes were not affected, elderly patients with spondylolisthesis might have a greater chance of facet fusion. This could be a cause of the limited range of motion at the index levels long after DDS.
Atlantoaxial fixation using C1 posterior arch screws: feasibility study, morphometric data, and biomechanical analysis
Authors: Cadena Gilbert , Duong Huy T. , Liu Jonathan J. , Kim Kee D.
Published: February 2019

OBJECTIVE

C1–2 is a highly mobile complex that presents unique surgical challenges to achieving biomechanical rigidity and fusion. Posterior wiring methods have been largely replaced with segmental constructs using the C1 lateral mass, C1 pedicle, C2 pars, and C2 pedicle. Modifications to reduce surgical morbidity led to the development of C2 laminar screws. The C1 posterior arch has been utilized mostly as a salvage technique, but recent data indicate that this method provides significant rigidity in flexion-extension and axial rotation. The authors performed biomechanical testing of a C1 posterior arch screw (PAS)/C2 pars screw construct, collected morphometric data from a population of 150 CT scans, and performed a feasibility study of a freehand C1 PAS technique in 45 cadaveric specimens.

METHODS

Cervical spine CT scans from 150 patients were analyzed to determine the average C1 posterior tubercle thickness and size of C1 posterior arches. Eight cadavers were used to compare biomechanical stability of intact specimens, C1 lateral mass/C2 pars screw, and C1 PAS/C2 pars screw constructs. Paired comparisons were made using repeated-measures ANOVA and Holm-Sidak tests. Forty-five cadaveric specimens were used to demonstrate the feasibility and safety of the C1 PAS freehand technique.

RESULTS

Morphometric data showed the average craniocaudal thickness of the C1 posterior tubercle was 12.3 ± 1.94 mm. Eight percent (12/150) of cases showed thin posterior tubercles or midline defects. Average posterior arch thickness was 6.1 ± 1.1 mm and right and left average posterior arch length was 28.7 mm ± 2.53 mm and 28.9 ± 2.29 mm, respectively. Biomechanical testing demonstrated C1 lateral mass/C2 pars and C1 PAS/C2 pars constructs significantly reduced motion in flexion-extension and axial rotation compared with intact specimens (p < 0.05). The C1 lateral mass/C2 pars screw construct provided significant rigidity in lateral bending (p < 0.05). There was no statistically significant difference between the two constructs in flexion-extension, lateral bending, or axial rotation. Of the C1 posterior arches, 91.3% were successfully cannulated using a freehand technique with a low incidence of cortical breach (4.4%).

CONCLUSIONS

This biomechanical analysis indicates equivalent stability of the C1 PAS/C2 pars screw construct compared with a traditional C1 lateral mass/C2 pars screw construct. Both provide significant rigidity in flexion-extension and axial rotation. Feasibility testing in 45 cadaveric specimens indicates a high degree of accuracy with low incidence of cortical breach. These findings are supported by a separate radiographic morphometric analysis.
Surgical management of spinal meningiomas: focus on unilateral posterior approach and anterior localization
Authors: Onken Julia , Obermüller Kathrin , Staub-Bartelt Franziska , Meyer Bernhard , Vajkoczy Peter , Wostrack Maria
Published: February 2019

OBJECTIVE

Spinal meningiomas (sMNGs) are relatively rare in comparison to intracranial MNGs. sMNGs localized anterior to the denticulate ligament (aMNGs) represent a surgically challenging subgroup. A high perioperative complication rate due to the need for complex surgical approaches has been described. In the present study, the authors report on their surgical experience that involves two institutions in which 207 patients underwent surgery for sMNGs. Special focus was placed on patients with aMNGs that were treated via a unilateral posterior approach (ULPA).

METHODS

Between 2005 and 2017, 207 patients underwent resection of sMNGs at one of two institutions. The following characteristics were assessed: tumor size and localization, surgical approach, duration of surgery, grade of resection, peri- and postoperative complication rates, and neurological outcome. Data were compared between the subgroups of patients according to the lesion’s relationship to the denticulate ligament and to surgical approach.

RESULTS

The authors identified 48 patients with aMNGs, 86 patients with lateral MNGs, and 76 patients with posterior MNGs (pMNGs). Overall, 66.6% of aMNGs and 64% of pMNGs were reached via a ULPA. aMNGs that were approached via a ULPA showed reduced duration of surgery (131 vs 224 minutes, p < 0.0001) and had surgical complication rates and neurological outcomes comparable to those of lesions that were approached via a bilateral approach. No significant differences in complication rate, outcomes, and extent of resection were seen between aMNGs and pMNGs.

CONCLUSIONS

The duration of surgery, extent of resection, and outcomes are comparable between aMNGs and pMNGs when removed via a ULPA. Thus, ULPA represents a safe route to achieve a gross-total resection, even in cases of aMNG.
An institutional intervention to modify opioid prescribing practices after lumbar spine surgery
Authors: Lovecchio Francis , Stepan Jeffrey G. , Premkumar Ajay , Steinhaus Michael E. , Sava Maria , Derman Peter , Kim Han Jo , Albert Todd
Published: February 2019

OBJECTIVE

Patients with lumbar spine pathology are at high risk for opioid misuse. Standardizing prescribing practices through an institutional intervention may reduce the overprescribing of opiates, leading to a decrease in the risk for opioid misuse and the number of pills available for diversion. Without quantitative data on the “minimum necessary quantity” of opioids appropriate for postdischarge prescriptions, the optimal method for changing existing prescribing practices is unknown. The purpose of this study was to determine whether mandatory provider education and prescribing guidelines could modify prescriber behavior and lead to a decreased amount of opioids prescribed at hospital discharge following lumbar spine surgery.

METHODS

Qualified staff were required to attend a mandatory educational conference, and a consensus method among the spine service was used to publish qualitative prescribing guidelines. Prescription data for 2479 patients who had undergone lumbar spine surgery were captured and compared based on the timing of surgery. The preintervention group consisted of 1177 patients who had undergone spine surgery in the period before prescriber education and guidelines (March 1, 2016–November 1, 2016). The postintervention group consisted of 1302 patients who had undergone spine surgery after the dissemination of the guidelines (February 1, 2017–October 1, 2017). Surgeries were classified as decompression or fusion procedures. Patients who had undergone surgeries for infection and patients on long-acting opioids were excluded.

RESULTS

For all lumbar spine surgeries (decompression and fusion), the mean amount of opioids prescribed at discharge was lower after the educational program and distribution of prescribing guidelines (629 ± 294 oral morphine equivalent [OME] preintervention vs 490 ± 245 OME postintervention, p < 0.001). The mean number of prescribed pills also decreased (81 ± 26 vs 66 ± 22, p < 0.001). Prescriptions for 81 or more tablets dropped from 65.5% to 25.5%. Tramadol was prescribed more frequently after prescriber education (9.9% vs 18.6%, p < 0.001). Refill rates within 6 weeks were higher after the institutional intervention (7.6% vs 12.4%, p < 0.07).

CONCLUSIONS

Qualitative guidelines and prescriber education are effective in reducing the amount of opioids prescribed at discharge and encouraging the use of weaker opioids. Coupling provider education with prescribing guidelines is likely synergistic in achieving larger reductions. The sustainability of these changes is yet to be determined.
How do physician demographics, training, social media usage, online presence, and wait times influence online physician review scores for spine surgeons?
Authors: Donnally Chester J. , McCormick Johnathon R. , Li Deborah J. , Maguire James A. , Barker Grant P. , Rush Augustus J. , Wang Michael Y.
Published: February 2019

OBJECTIVE

The purpose of this study was to assess the impact of certain demographics, social media usage, and physician review website variables for spine surgeons across Healthgrades.com (Healthgrades), Vitals.com (Vitals), and Google.com (Google).

METHODS

Through a directory of registered North American Spine Society (NASS) physicians, we identified spine surgeons practicing in Texas (107 neurosurgery trained, 192 orthopedic trained). Three physician rating websites (Healthgrades, Vitals, Google) were accessed to obtain surgeon demographics, training history, practice setting, number of ratings/reviews, and overall score (January 2, 2018–January 16, 2018). Using only the first 10 search results from Google.com, we then identified whether the surgeon had a website presence or an accessible social media account on Facebook, Twitter, and/or Instagram.

RESULTS

Physicians with either a personal or institutional website had a higher overall rating on Healthgrades compared to those who did not have a website (p < 0.01). Nearly all spine surgeons had a personal or institutional website (90.3%), and at least 1 accessible social media account was recorded for 43.5% of the spine surgeons in our study cohort (39.5% Facebook, 10.4% Twitter, 2.7% Instagram). Social media presence was not significantly associated with overall ratings across all 3 sites, but it did significantly correlate with more comments on Healthgrades. In multivariable analysis, increasing surgeon age was significantly associated with a lower overall rating across all 3 review sites (p < 0.05). Neurosurgeons had higher overall ratings on Vitals (p = 0.04). Longer wait times were significantly associated with a lower overall rating on Healthgrades (p < 0.0001). Overall ratings from all 3 websites correlated significantly with each other, indicating agreement between physician ratings across different platforms.

CONCLUSIONS

Longer wait times, increasing physician age, and the absence of a website are indicative of lower online review scores for spine surgeons. Neurosurgery training correlated with a higher overall review score on Vitals. Having an accessible social media account does not appear to influence scores, but it is correlated with increased patient feedback on Healthgrades. Identification of ways to optimize patients’ perception of care are important in the future of performance-based medicine.
Morphologic variations of the second cervical vertebra in Down syndrome compared with age-matched peers
Authors: Hofler Ryan C. , Heiferman Daniel M. , Molefe Ayrin , LeDuc Ryan , Johans Stephen J. , Rosenblum Jordan D. , Nockels Russ P. , Jones G. Alexander
Published: February 2019

OBJECTIVE

Atlantoaxial instability is an important cause of pain and neurological dysfunction in patients with Down syndrome (DS), frequently requiring instrumented fusion of the upper cervical spine. This study provides a quantitative analysis of C2 morphology in DS patients compared with their peers without DS to identify differences that must be considered for the safe placement of instrumentation.

METHODS

A retrospective chart review identified age-matched patients with and without DS with a CT scan of the cervical spine. Three-dimensional reconstructions of these scans were made with images along the axis of, and perpendicular to, the pars, lamina, facet, and transverse foramen of C2 bilaterally. Two of the authors performed independent measurements of anatomical structures using these images, and the average of the 2 raters’ measurements was recorded. Pedicle height and width; pars axis length (the distance from the facet to the anterior vertebral body through the pars); pars rostrocaudal angle (angle of the pars axis length to the endplate of C2); pars axial angle (angle of the pars axis length to the median coronal plane); lamina height, length, and width; lamina angle (angle of the lamina length to the median coronal plane); and transverse foramen posterior distance (the distance from the posterior wall of the transverse foramen to the tangent of the posterior vertebral body) were measured bilaterally. Patients with and without DS were compared using a mixed-effects model accounting for patient height.

RESULTS

A total of 18 patients with and 20 patients without DS were included in the analysis. The groups were matched based on age and sex. The median height was 147 cm (IQR 142–160 cm) in the DS group and 165 cm (IQR 161–172 cm) in the non-DS group (p < 0.001). After accounting for variations in height, the mean pars rostrocaudal angle was greater (50.86° vs 45.54°, p = 0.004), the mean transverse foramen posterior distance was less (−1.5 mm vs +1.3 mm, p = 0.001), and the mean lamina width was less (6.2 mm vs 7.7 mm, p = 0.038) in patients with DS.

CONCLUSIONS

Patients with DS had a steeper rostrocaudal trajectory of the pars, a more posteriorly positioned transverse foramen posterior wall, and a narrower lamina compared with age- and sex-matched peers. These variations should be considered during surgical planning, as they may have implications to safe placement of instrumentation.
Defining a new neurosurgical complication classification: lessons learned from a monthly Morbidity and Mortality conference
Authors: Gozal Yair M. , Aktüre Erinç , Ravindra Vijay M. , Scoville Jonathan P. , Jensen Randy L. , Couldwell William T. , Taussky Philipp
Published: February 2019

OBJECTIVE

The absence of a commonly accepted standardized classification system for complication reporting confounds the recognition, objective reporting, management, and avoidance of perioperative adverse events. In the past decade, several classification systems have been proposed for use in neurosurgery, but these generally focus on tallying specific complications and grading their effect on patient morbidity. Herein, the authors propose and prospectively validate a new neurosurgical complication classification based on understanding the underlying causes of the adverse events.

METHODS

A new complication classification system was devised based on the authors’ previous work on morbidity in endovascular surgery. Adverse events were prospectively compiled for all neurosurgical procedures performed at their tertiary care academic medical center over the course of 1 year into 5 subgroups: 1) indication errors; 2) procedural errors; 3) technical errors; 4) judgment errors; and 5) critical events. The complications were presented at the monthly institutional Morbidity and Mortality conference where, following extensive discussion, they were assigned to one of the 5 subgroups. Additional subgroup analyses by neurosurgical subspecialty were also performed.

RESULTS

A total of 115 neurosurgical complications were observed and analyzed during the study period. Of these, nearly half were critical events, while technical errors accounted for approximately one-third of all complications. Within neurosurgical subspecialties, vascular neurosurgery (36.5%) had the most complications, followed by spine & peripheral nerve (21.7%), neuro-oncology (14.8%), cranial trauma (13.9%), general neurosurgery (12.2%), and functional neurosurgery (0.9%).

CONCLUSIONS

The authors’ novel neurosurgical complication classification system was successfully implemented in a prospective manner at their high-volume tertiary medical center. By employing the well-established Morbidity and Mortality conference mechanism, this simple system may be easily applied at other neurosurgical centers and may allow for uniform analyses of perioperative morbidity and the introduction of corrective initiatives.
Revascularization surgery for symptomatic non-moyamoya intracranial arterial stenosis or occlusion
Authors: Gunawardena Manuri , Rogers Jeffrey M. , Stoodley Marcus A. , Morgan Michael K.
Published: February 2019

OBJECTIVE

Previous trials rejected a role of extracranial-to-intracranial bypass surgery for managing symptomatic atheromatous disease. However, hemodynamic insufficiency may still be a rationale for surgery, provided the bypass can be performed with low morbidity and patency is robust.

METHODS

Consecutive patients undergoing bypass surgery for symptomatic non-moyamoya intracranial arterial stenosis or occlusion were retrospectively identified. The clinical course and surgical outcomes of the cohort were evaluated at 6 weeks, 6 months, and annually thereafter.

RESULTS

From 1992 to 2017, 112 patients underwent 127 bypasses. The angiographic abnormality was arterial occlusion in 80% and stenosis in 20%. Procedures were performed to prevent future stroke (76%) and stroke reversal (24%), with revascularization using an arterial pedicle graft in 80% and venous interposition graft (VIG) in 20%. A poor outcome (bypass occlusion, new stroke, new neurological deficit, or worsening neurological deficit) occurred in 8.9% of patients, with arterial pedicle grafts (odds ratio [OR] 0.15), bypass for prophylaxis against future stroke (OR 0.11), or anterior circulation bypass (OR 0.17) identified as protective factors. Over the first 8 years following surgery the 66 cases exhibiting all three of these characteristics had minimal risk of a poor outcome (95% confidence interval 0%–6.6%).

CONCLUSIONS

Prophylactic arterial pedicle bypass surgery for anterior circulation ischemia is associated with high graft patency and low stroke and surgical complication rates. Higher risks are associated with acute procedures, typically for posterior circulation pathology and requiring VIGs. A carefully selected subgroup of individuals with hemodynamic insufficiency and ischemic symptoms is likely to benefit from cerebral revascularization surgery.