Immunonutrition with Omega-3 Fatty Acid Supplementation in Severe TBI: Retrospective Analysis of Patient Characteristics and Outcomes

Background

Early evidence-based medical interventions to improve patient outcomes after traumatic brain injury (TBI) are lacking. In patients admitted to the ICU after TBI, optimization of nutrition is an emerging field of interest. Specialized enteral nutrition (EN) formulas that include immunonutrition containing omega-3 polyunsaturated fatty acids (n-3 PUFAs) have been developed and are used for their proposed anti-inflammatory and pro-immune properties; however, their use has not been rigorously studied in human TBI populations.

Methods

A single-center, retrospective, descriptive observational study was conducted at LAC + USC Medical Center. Patients with severe TBI (sTBI, Glasgow Coma Scale score ≤ 8) who remained in the ICU for ≥ 2 weeks and received EN were identified between 2017 and 2022 using the institutional trauma registry. Those who received immunonutrition formulas containing n-3 PUFAs were compared to those who received standard, polymeric EN in regard to baseline characteristics, clinical markers of inflammation and immune function, and short-term clinical outcomes.

Results

A total of 151 patients with sTBI were analyzed. Those who received immunonutrition with n-3 PUFA supplementation were more likely to be male, younger, Hispanic/Latinx, and have polytrauma needing non-central nervous system surgery. No differences in clinical markers of inflammation or infection rate were found. In multivariate regression analysis, immunonutrition was associated with reduced hospital length of stay (LOS). ICU LOS was also reduced in the subgroup of patients with polytrauma and TBI.

Conclusion

This study identifies important differences in patient characteristics and outcomes associated with the EN formula prescribed. Study results can directly inform a prospective pragmatic study of immunonutrition with n-3 PUFA supplementation aimed to confirm the biomechanistic and clinical benefits of the intervention.

Unusual Pattern of Arterial Macrothrombosis Causing Stroke in a Young Adult Recovered from COVID-19

Coronavirus disease-19 (COVID-19) pandemic continues to grow all over the world. Neurological manifestations related to COVID-19, including acute ischemic Stroke (AIS), have been reported in recent studies. In most of these, the patients are older, have multiple co-morbidities as risk factors for AIS and have developed a severe respiratory illness. Herein, we report a 36-year-old man with no significant past medical history who recently recovered from a mild COVID-19 infection and presented with unusual pattern of arterial macrothrombosis causing AIS. When the AIS happened, he had no COVID-19 related symptoms, had two negative screening tests for the infection and his chest CT was unremarkable.

A3-A3 Anastomosis in the Management of Complex Anterior Cerebral Artery Aneurysms: Experience With in Situ Bypass and Lessons Learned From Pseudoaneurysm Cases

BACKGROUND

A3-A3 side-to-side bypass is an intracranial-to-intracranial (IC-IC) revascularization option when aneurysm treatment involves occlusion of one anterior cerebral artery (ACA).

OBJECTIVE

To describe applications of A3-A3 side-to-side bypass in the management of ACA true and pseudoaneurysms along with a review of pertinent literature.

METHODS

Six consecutive patients undergoing an A3-A3 bypass as part of their aneurysm management, representing a single-surgeon experience in a 2-yr period, were included in this retrospective review of a prospectively collected database.

RESULTS

Three male and three female patients with a median (range) age of 41.5 (11-69) years representing four ruptured and two unruptured aneurysms were included. Two of the aneurysms were communicating while four were postcommunicating from which three were pseudoaneurysms. Complete aneurysm obliteration was achieved in 5/6 cases. Bypass patency was evaluated in all cases intra- and postoperatively. Good outcomes (modified Rankin Scale score ≤ 2) at follow-up were observed in 4/6 patients. An improvement in mRS scores at the most recent follow-up as compared to preoperative status was achieved in three while scores remained the same in two patients. Ischemic complications related to aneurysm treatment were observed in two patients, both of which achieved good functional recovery upon follow-up. One patient deceased postoperatively due to progression of vasospasm-related infarcts.

CONCLUSION

A3-A3 bypass in the management of true as well as pseudoaneurysms of the ACA can achieve good postoperative outcomes in selected patients. Prompt diagnosis and aggressive surgical treatment needs to be pursued if a vessel injury with pseudoaneurysm formation is suspected.

Predictors of Venous Thromboembolism After Nonemergent Craniotomy: A Nationwide Readmission Database Analysis

BACKGROUND

Venous thromboembolism (VTE) is responsible for many hospital readmissions each year, particularly among postsurgical cohorts. Because early and indiscriminate VTE prophylaxis carries catastrophic consequences in postcraniotomy cohorts, identifying factors associated with a high risk for thromboembolic complications is important for guiding postoperative management.

OBJECTIVE

To determine VTE incidence in patients undergoing nonemergent craniotomy and to evaluate for factors that predict 30-day and 90-day readmission with VTE.

METHODS

The 2010-2014 cohorts of the Nationwide Readmissions Database were used to generate a large heterogeneous craniotomy sample.

RESULTS

There were 89,450 nonemergent craniotomies that met inclusion criteria. Within 30 days, 1513 patients (1.69%) were readmitted with VTE diagnoses; among them, 678 (44.8%) had a diagnosis of deep vein thrombosis alone, 450 (29.7%) had pulmonary embolism alone, and 385 (25.4%) had both. The corresponding 30-day deep vein thrombosis and pulmonary embolism incidences were 1.19% and 0.93%, respectively. In multivariate analysis, several factors were significantly associated with VTE readmission, namely, craniotomy for tumor, corticosteroids, advanced age, greater length of stay, and discharge to institutional care.

CONCLUSIONS

Craniotomies for tumor, corticosteroids, advanced age, prolonged length of stay, and discharge to institutional care are significant predictors of VTE readmission. The implication of steroids, coupled with their ubiquity in neurosurgery, makes them a potentially modifiable risk factor and a prime target for VTE reduction in craniotomy cohorts. Furthermore, the fact that dose is proportional to VTE risk in the literature suggests that careful consideration should be given toward decreasing regimens in situations in which use of a lower dose might prove equally sufficient.

Treatment at Safety-Net Hospitals Is Associated with Delays in Coil Embolization in Patients with Subarachnoid Hemorrhage

BACKGROUND

Successful endovascular management of aneurysmal subarachnoid hemorrhage (aSAH) requires timely access to substantial resources. Prior studies suggest an association between time to treatment and patient outcome. Patients treated at safety-net hospitals are thought to be particularly vulnerable to disparities in access to interventions that require substantial technologic resources. We hypothesized that patients with aSAH treated at safety-net hospitals are at greater risk for delayed access to endovascular treatment.

METHODS

Adults undergoing endovascular coiling procedures between 2002 and 2011 in the Nationwide Inpatient Sample were included. Hospitals in the quartile with the highest proportion of Medicaid or uninsured patients were defined as safety-net hospitals. A multivariate model including patient-level and hospital-level factors was constructed to permit analysis of delays in endovascular treatment (defined as time to treatment >3 days).

RESULTS

Analysis included 7109 discharges of patients with aSAH undergoing endovascular coil embolization procedures from 2002 to 2011. Median time to coil embolization in all patients was 1 day; 10.1% of patients waited >3 days until treatment. In multivariate analysis, patients treated at safety-net hospitals were more likely to have a prolonged time to coil embolization (odds ratio = 1.32, P < 0.01) compared with patients treated at low-burden hospitals.

CONCLUSIONS

After controlling for patient and hospital factors, individuals with aSAH treated at safety-net hospitals from 2002 to 2011 were more likely to have a delay to endovascular coil embolization than individuals treated at non-safety-net hospitals. This disparity could affect patient outcomes.

In situ administration of abciximab for thrombus resolution during intracranial bypass surgery: case report

Abciximab is a glycoprotein IIb/IIIa receptor antagonist that functions to prevent platelet aggregation, thus reducing thrombus initiation and propagation. It has been widely used during percutaneous endovascular interventions, such as aneurysm coil embolization, angioplasty, atherectomy, and stent placement, as both a preventative and a salvage therapy. The use of abciximab in cardiac and neurosurgical procedures has been associated with a reduced incidence of ischemic complications and a decreased need for repeated intervention. In these settings, abciximab has been delivered transarterially via a microcatheter or infused intravenously for systemic administration. The authors describe novel in situ delivery of abciximab as an agent to dissolve "white clots," which are composed primarily of platelets, during an intracranial superficial temporal artery to middle cerebral artery bypass in a 28-year-old woman with severe intracranial occlusive disease. Abciximab was able to resolve multiple platelet-based clots after unsuccessful attempts with conventional clot dispersal techniques, such as heparinized saline, tissue plasminogen activator, mechanical passage of a wire through the vessel lumen, and multiple takedowns and re-anastomosis. After abciximab was administered, patency was demonstrated intraoperatively using indocyanine green dye and confirmed postoperatively at 1 and 10 months via CT angiography. The in situ use of abciximab as an agent to disperse a thrombus during intracranial bypass surgery is novel and has not previously been described in the literature, and serves as an additional tool during intracranial vessel bypass surgery.

Angiographic and clinical outcomes of balloon remodeling versus unassisted coil embolization in the ruptured aneurysm cohort of the GEL THE NEC study

BACKGROUND AND PURPOSE

GEL THE NEC (GTN) was a multicenter prospective registry developed to assess the safety and efficacy of HydroSoft coils in treating intracranial aneurysms. We compared the angiographic and clinical outcomes of aneurysms treated with balloon assisted coil embolization (BACE) versus unassisted coil embolization (CE) in the ruptured aneurysm cohort.

MATERIALS AND METHODS

GTN was performed at 27 centers in five countries. Patients aged 21-90 years with a ruptured aneurysm 3-15 mm in size were eligible for enrollment. We analyzed demographics/comorbidities, aneurysm location, and geometry, including maximum diameter, neck size, and dome to neck ratio, immediate and long term angiographic outcomes (graded by an independent core laboratory using the modified Raymond Scale), and procedure related adverse events. Angiographic and clinical outcomes were studied using χ²and t tests.

RESULTS

Of the 599 patients in the GTN, 194 met the inclusion criteria. 84 were treated with BACE and 110 with CE. There were more prior smokers in the BACE group (p=0.01). The BACE group also had more vertebrobasilar aneurysms (p=0.006) and a larger mean neck size (p=0.02). More aneurysms were immediately completely occluded in the BACE group (p=0.02) Procedure- related major morbidity and mortality were no different between the techniques (p=0.4 and p=1, respectively).

CONCLUSIONS

In this prospective ruptured aneurysm cohort from the GTN, BACE resulted in greater occlusion rates compared with unassisted CE with similar morbi-mortality.

Neuroprotective delivery platforms as an adjunct to mechanical thrombectomy

Despite the success of numerous neuroprotective strategies in animal and preclinical stroke models, none have effectively translated to clinical medicine. A multitude of influences are likely responsible. Two such factors are inefficient recanalization strategies for large vessel occlusions and suboptimal delivery methods/platforms for neuroprotective agents. The recent endovascular stroke trials have established a new paradigm for large vessel stroke treatment. The associated advent of advanced mechanical revascularization devices and new stroke technologies help address each of these existing gaps. A strategy combining effective endovascular revascularization with administration of neuroprotective therapies is now practical and could have additive, if not synergistic, effects. This review outlines past and current neuroprotective strategies assessed in acute stroke trials. The discussion focuses on delivery platforms and their potential applicability to endovascular stoke treatment.

Impact of the 2003 ACGME Resident Duty Hour Reform on Hospital-Acquired Conditions: A National Retrospective Analysis

BACKGROUND

The Accreditation Council for Graduate Medical Education reforms in 2003 instituted an 80-hour weekly limit for resident physicians. Critics argue that these restrictions have increased handoffs among residents and the potential for a decline in patient safety. "Never events" hospital-acquired conditions (HACs) are a set of preventable events used as a quality metric in hospital safety analyses.

OBJECTIVE

This analysis evaluated post-work hour reform effects on HAC incidence for US hospital inpatients, using the National Inpatient Sample.

METHODS

Data were collected from 2000-2002 (pre-2003) and 2004-2006 (post-2003) time periods. HAC incidence in academic and non-academic centers was evaluated in multivariate analysis assessing for likelihood of HAC occurrence, prolonged length of stay (pLOS), and increased total charges.

RESULTS

The data encompassed approximately 111 million pre-2003 and 117 million post-2003 admissions. Patients were 10% more likely to incur a HAC in the post-2003 versus pre-2003 era (odds ratio [OR] = 1.10; 95% confidence interval [CI] 1.06-1.14; P < .01). Teaching hospitals exhibited an 18% (OR = 1.18; 95% CI 1.11-1.27; P < .01) increase in HAC likelihood, with no change in nonteaching settings (OR = 1.03; 95% CI 1.00-1.06; P > .05). Patients with ≥ 1 HAC were associated with a 60% likelihood of elevated charges (OR = 1.60; 95% CI 1.50-1.72; P < .01) and 65% likelihood of pLOS (OR = 1.65; 95% CI 1.60-1.70; P < .01).

CONCLUSIONS

Post-2003 era patients were associated with 10% increased likelihood of HAC, with effects noted primarily at teaching hospitals.

GEL THE NEC: a prospective registry evaluating the safety, ease of use, and efficacy of the HydroSoft coil as a finishing device

Background and purpose

The HydroSoft coil was developed as a finishing coil, ideally to be placed along the aneurysm neck to enhance intracranial aneurysm healing. The GEL THE NEC (Gaining Efficacy Long Term: Hydrosoft, an Emerging, New, Embolic Coil) multicenter registry was developed to assess the safety and efficacy of HydroSoft coils in treating intracranial aneurysms. We report angiographic and clinical results of this prospective registry.

Materials and methods

GEL THE NEC was performed at 27 centers in five countries. Patients aged 21–90 years with a ruptured or unruptured aneurysm 3–15 mm in size were eligible for enrollment. The following variables were obtained: demographics/comorbidities, aneurysm geometry, adjunctive devices used, proportion of patients in whom HydroSoft coils were successfully placed, and long-term angiographic outcomes (graded by an independent core laboratory using the Modified Raymond Scale), and procedure-related adverse events. Predictors of good angiographic outcome were studied using χ2 and t-tests.

Results

A total of 599 patients with 599 aneurysms were included in this study. HydroSoft coils were successfully deployed in 577 (96.4%) patients. Procedure-related major morbidity and mortality were 0.5% (3/599) and 1.3% (8/599), respectively. The most common perioperative complications were iatrogenic vasospasm (30/599, 5.0%), thromboemboli (27/599, 4.5%), and aneurysm perforation (16/599, 2.7%). At last angiographic follow-up (mean 9.0±6.3 months), the complete occlusion rate was 63.2% (280/442) and near complete occlusion rate was 25.2% (107/442). The core laboratory read recanalization rate was 10.8% (46/425) and the retreatment rate was 3.4% (20/599).

Conclusions

Endovascular treatment of intracranial aneurysms with HydroSoft coils resulted in complete/near complete occlusion rates of 88% and a major complication rate of 1.8%.

Trial registration number

NCT01000675.

Evidence-based guidelines for the management of large hemispheric infarction : a statement for health care professionals from the Neurocritical Care Society and the German Society for Neuro-intensive Care and Emergency Medicine

Large hemispheric infarction (LHI), also known as malignant middle cerebral infarction, is a devastating disease associated with significant disability and mortality. Clinicians and family members are often faced with a paucity of high quality clinical data as they attempt to determine the most appropriate course of treatment for patients with LHI, and current stroke guidelines do not provide a detailed approach regarding the day-to-day management of these complicated patients. To address this need, the Neurocritical Care Society organized an international multidisciplinary consensus conference on the critical care management of LHI. Experts from neurocritical care, neurosurgery, neurology, interventional neuroradiology, and neuroanesthesiology from Europe and North America were recruited based on their publications and expertise. The panel devised a series of clinical questions related to LHI, and assessed the quality of data related to these questions using the Grading of Recommendation Assessment, Development and Evaluation guideline system. They then developed recommendations (denoted as strong or weak) based on the quality of the evidence, as well as the balance of benefits and harms of the studied interventions, the values and preferences of patients, and resource considerations.

Racial and socioeconomic disparities in outcomes following pediatric cerebrospinal fluid shunt procedures

OBJECT Racial and socioeconomic disparities within the US health care system are a growing concern. Despite extensive research and efforts to narrow such disparities, minorities and economically disadvantaged patients continue to exhibit inferior health care outcomes. Disparities in the delivery of pediatric neurosurgical care are understudied. Authors of this study examine the impact of race and socioeconomic status on outcomes following pediatric CSF shunting procedures. METHODS Discharge information from the 2000, 2003, 2006, and 2009 Kids' Inpatient Database for individuals (age < 21 years) with a diagnosis of hydrocephalus who had undergone CSF shunting procedures was abstracted for analysis. Multivariate logistic regression analyses, adjusting for patient and hospital factors and annual CSF shunt procedure volume, were performed to evaluate the effects of race and payer status on the likelihood of inpatient mortality and nonroutine hospital discharge (that is, not to home). RESULTS African American patients (p < 0.05) had an increased likelihood of inpatient death and nonroutine discharge compared with white patients. Furthermore, Medicaid patients had a significantly higher likelihood of nonroutine discharge (p < 0.05) as compared with privately insured patients. CONCLUSIONS Findings in this study, which utilized US population-level data, suggest the presence of racial and socioeconomic status outcome disparities following pediatric CSF shunting procedures. Further studies on health disparities in this population are warranted.

Incidence of "never events" among weekend admissions versus weekday admissions to US hospitals: national analysis

OBJECTIVE

To evaluate the association between weekend admission to hospital and 11 hospital acquired conditions recently considered by the Centers for Medicare and Medicaid as "never events" for which resulting healthcare costs are not reimbursed.

DESIGN

National analysis.

SETTING

US Nationwide Inpatient Sample discharge database.

PARTICIPANTS

351 million patients discharged from US hospitals, 2002-10.

MAIN OUTCOME MEASURES

Univariate rates and multivariable likelihood of hospital acquired conditions among patients admitted on weekdays versus weekends, as well as the impacts of these events on prolonged length of stay and total inpatient charges.

RESULTS

From 2002 to 2010, 351,170,803 patients were admitted to hospital, with 19% admitted on a weekend. Hospital acquired conditions occurred at an overall frequency of 4.1% (5.7% among weekend admissions versus 3.7% among weekday admissions). Adjusting for patient and hospital cofactors the probability of having one or more hospital acquired conditions was more than 20% higher in weekend admissions compared with weekday admissions (odds ratio 1.25, 95% confidence interval 1.24 to 1.26, P<0.01). Hospital acquired conditions have a negative impact on both hospital charges and length of stay. At least one hospital acquired condition was associated with an 83% (1.83, 1.77 to 1.90, P<0.01) likelihood of increased charges and 38% likelihood of prolonged length of stay (1.38, 1.36 to 1.41, P<0.01).

CONCLUSION

Weekend admission to hospital is associated with an increased likelihood of hospital acquired condition, cost, and length of stay. Future protocols and staffing regulations must be tailored to the requirements of this high risk subgroup.

Angioarchitectural evolution of clival dural arteriovenous fistulas in two patients

Dural arteriovenous fistulas (dAVFs) may present in a variety of ways, including as carotid-cavernous sinus fistulas. The ophthalmologic sequelae of carotid-cavernous sinus fistulas are known and recognizable, but less commonly seen is the rare clival fistula. Clival dAVFs may have a variety of potential anatomical configurations but are defined by the involvement of the venous plexus just overlying the bony clivus. Here we present two cases of clival dAVFs that most likely evolved from carotid-cavernous sinus fistulas.

Transarterial embolization of an anterior fossa cranial base dural arteriovenous fistula

Open surgical disconnection has long been the treatment of choice for dural arteriovenous fistulas (dAVFs) of the anterior cranial fossa. However, advanced patient age and the presence of medical comorbidities can substantially increase the risk of craniotomy and favor a less invasive endovascular approach. Optimal positioning within the distal ophthalmic artery, beyond the origin of the central retinal branch, is achievable using current microcatheter technology and embolic materials. Here we present the case of an 88-year-old female with an incidentally discovered dAVF of the anterior cranial fossa. Angiographic cure was achieved with one-stage Onyx embolization. The video can be found here: http://youtu.be/KVE0fUIECQM .

Balloon-assisted transarterial embolization of type 1 spinal dural arteriovenous fistula

Type 1 spinal dural arteriovenous fistula (dAVF) constitute the vast majority of all spinal vascular malformations. Here we present the case of a 71-year-old male with progressive myelopathy, lower-extremity weakness and numbness, and urinary incontinence. MRI imaging of the thoracic spine demonstrated cord edema, and catheter spinal angiography confirmed a type 1 spinal dAVF. The fistula was supplied by small dural branches of the left L-2 segmental artery. Angiographic cure was achieved with a one-stage procedure in which coils were used to occlude the distal segmental vessels, followed by balloon-assisted embolization with Onyx. The video can be found here: http://youtu.be/8aehJbueH0U .

The impact of patient age and comorbidities on the occurrence of "never events" in cerebrovascular surgery: an analysis of the Nationwide Inpatient Sample

OBJECT

As health care administrators focus on patient safety and cost-effectiveness, methodical assessment of quality outcome measures is critical. In 2008 the Centers for Medicare and Medicaid Services (CMS) published a series of "never events" that included 11 hospital-acquired conditions (HACs) for which related costs of treatment are not reimbursed. Cerebrovascular procedures (CVPs) are complex and are often performed in patients with significant medical comorbidities.

METHODS

This study examines the impact of patient age and medical comorbidities on the occurrence of CMS-defined HACs, as well as the effect of these factors on the length of stay (LOS) and hospitalization charges in patients undergoing common CVPs.

RESULTS

The HACs occurred at a frequency of 0.49% (1.33% in the intracranial procedures and 0.33% in the carotid procedures). Falls/trauma (n = 4610, 72.3% HACs, 357 HACs per 100,000 CVPs) and catheter-associated urinary tract infections (n = 714, 11.2% HACs, 55 HACs per 100,000 CVPs) were the most common events. Age and the presence of ≥ 2 comorbidities were strong independent predictors of HACs (p < 0.0001). The occurrence of HACs negatively impacts both LOS and hospital costs. Patients with at least 1 HAC were 10 times more likely to have prolonged LOS (≥ 90th percentile) (p < 0.0001), and 8 times more likely to have high inpatient costs (≥ 90th percentile) (p < 0.0001) when adjusting for patient and hospital factors.

CONCLUSIONS

Improved quality protocols focused on individual patient characteristics might help to decrease the frequency of HACs in this high-risk population. These data suggest that risk adjustment according to underlying patient factors may be warranted when considering reimbursement for costs related to HACs in the setting of CVPs.

Complications of endovascular treatment for acute stroke in the SWIFT trial with solitaire and Merci devices

BACKGROUND AND PURPOSE

Treatment of patients with ischemic stroke after endovascular treatment requires in-depth knowledge of complications. The goal of this study was to make endovascular treatment for acute ischemic stroke safer through an in-depth review of the major periprocedural complications observed in the Solitaire FR With Intention for Thrombectomy (SWIFT) trial.

MATERIALS AND METHODS

The SWIFT data base was searched for major peri-procedural complications defined as symptomatic intracranial hemorrhage within 36 hours, SAH, air emboli, vessel dissection, major groin complications, and emboli to new vascular territories.

RESULTS

Major peri-procedural complications occurred in 18 of 144 patients (12.5%) as follows: symptomatic intracranial hemorrhage, 4.9%; air emboli, 1.4%; vessel dissection, 4.2%; major groin complications, 2.8%; and emboli to new vascular territories, 0.7%. Rates of symptomatic intracranial bleeding by subtype were PH1, 0.7%; PH2, 0.7% (PH1 indicates hematoma within ischemic field with some mild space-occupying effect but involving ≤ 30% of the infarcted area; PH2, hematoma within ischemic field with space-occupying effect involving >30% of the infarcted area); intracranial hemorrhage remote from ischemic zone, 0%; intraventricular hemorrhage, 0.7%; and SAH, 3.5%. We did not observe any statistically significant associations of peri-procedural complications with age; type of treatment center; duration of stroke symptoms; NIHSS score, IV thrombolytics, atrial fibrillation, site of vessel occlusion; rescue therapy administered after endovascular treatment; or device. Comparing the Merci with the Solitaire FR retrieval device, we observed symptomatic cerebral hemorrhage (10.9% versus 1.1%; P = .013); symptomatic SAH (7.3% versus 1.1%; P = .07), air emboli (1.8% versus 1.1%; P = 1.0), emboli to new vascular territories (1.8% versus 0%; P = .38), vessel dissection (1.8% versus 4.5%; P = .65), and major groin complications (3.6% versus 7.9%; P = .48). Angiographic vasospasm was common but without clinical sequelae.

CONCLUSIONS

Understanding of procedural complications is important for treatment of patients with stroke after endovascular treatment. We observed fewer endovascular complications with the Solitaire FR device treatment compared with Merci device treatment, particularly symptomatic cerebral hemorrhage.

Racial and socioeconomic disparities in access to mechanical revascularization procedures for acute ischemic stroke

BACKGROUND

Mechanical revascularization procedures performed for treatment of acute ischemic stroke have increased in recent years. Data suggest association between operative volume and mortality rates. Understanding procedural allocation and patient access patterns is critical. Few studies have examined these demographics.

METHODS

Data were collected from the 2008 Nationwide Inpatient Sample database. Patients hospitalized with ischemic stroke and the subset of individuals who underwent mechanical thrombectomy were characterized by race, payer source, population density, and median wealth of the patient's zip code. Demographic data among patients undergoing mechanical thrombectomy procedures were examined. Stroke admission demographics were analyzed according to thrombectomy volume at admitting centers and patient demographics assessed according to the thrombectomy volume at treating centers.

RESULTS

Significant allocation differences with respect to frequency of mechanical thrombectomy procedures among stroke patients existed according to race, expected payer, population density, and wealth of the patient's zip code (P < .0001). White, Hispanic, and Asian/Pacific Islander patients received endovascular treatment at higher rates than black and Native American patients. Compared with the white stroke patients, black (P < .001), Hispanic (P < .001), Asian/Pacific Islander (P < .001), and Native American stroke patients (P < .001) all demonstrated decreased frequency of admission to hospitals performing mechanical thrombectomy procedures at high volumes. Among treated patients, blacks (P = .0876), Hispanics (P = .0335), and Asian/Pacific Islanders (P < .001) demonstrated decreased frequency in mechanical thrombectomy procedures performed at high-volume centers when compared with whites. While present, socioeconomic disparities were not as consistent or pronounced as racial differences.

CONCLUSIONS

We demonstrate variances in endovascular acute stroke treatment allocation according to racial and socioeconomic factors in 2008. Efforts should be made to monitor and address potential disparities in treatment utilization.

Delayed cavernous carotid artery pseudoaneurysm caused by absorbable plate following transsphenoidal surgery: case report and review of the literature

Background Bioabsorbable plates are frequently utilized in the repair of skull base defects following transsphenoidal operations. Traumatic intracranial pseudoaneurysms are a rare complication of transsphenoidal surgery. To date, iatrogenic carotid pseudoaneurysm associated with the use of an absorbable plate has been reported once. Results A 57-year-old man with a large nonfunctional pituitary macroadenoma underwent an endoscopic transsphenoidal operation with gross total resection. An absorbable plate was placed extradurally to reconstruct the sellar floor. He experienced delayed repeated epistaxis, followed by a right middle cerebral artery distribution embolic stroke. Computed tomorgraphy (CT) angiogram 6 weeks postoperatively revealed a 6 × 4 mm pseudoaneurysm located on the medial wall of the right cavernous internal carotid artery. Stent coiling was used to successfully obliterate the pseudoaneurysm, and the patient fully recovered. Conclusion Delayed erosion of the carotid artery wall caused by a plate used to reconstruct the sellar floor may manifest with epistaxis or embolic stroke. The authors' preference is to avoid insertion of a rigid plate for sellar floor reconstruction in the absence of intraoperative cerebrospinal fluid (CSF) leaks, unless it is required to buttress a large skull base defect. Short-segment embolization with stent coiling is the preferred treatment option for carotid pseudoaneurysms following transsphenoidal operations.

Abstract TP390: Ethnic and Regional Disparities in Access to Endovascular Embolectomy for Acute Ischemic Stroke

Background: Endovascular stroke treatment volume has significantly increased in recent years. Data from the Nationwide Inpatient Sample (NIS) database in 2008 demonstrates an association between improved outcomes and centers that perform substantial procedural volume (>10/year). Few reports have described demographics of patient populations or centers performing mechanical thrombectomy.

Methods: We collected data from the 2008 NIS database for patients hospitalized for ischemic stroke, and those undergoing mechanical clot retrieval. Patients were characterized by ethnicity, payment source, and regional hospital variables of population density and median zipcode wealth. Patients were evaluated for admission and treatment at substantial thrombectomy volume centers.

Results: Approximately 1.1 million patients were hospitalized for acute stroke, with 2749 patients receiving mechanical thrombectomy in 2008. Asian patients received the highest frequency of intervention (0.39%) with Blacks and Native Americans receiving the lowest (0.18%, 0.17%). Patients from zipcodes with highest median wealth most frequently received intervention (0.29%, p<0.001). Among all stroke patients, Whites, Hispanics, individuals in highest salaried zip codes and patients residing in counties with population > 1 million were most often admitted to centers with substantial endovascular procedural volume (all, p<0.001 in multivariate analysis). Among those undergoing thrombectomy, Hispanics (p=0.03, OR 0.654 [0.442,0.967]), Asians (p=<0.001, 0.205 [0.120,0.350]) and Blacks (p=0.09, OR 0.717[0.489,1.050]), were treated less frequently than Whites at substantial volume centers.

Conclusion: Native Americans and Blacks received the lowest frequency of thrombectomy for acute ischemic stroke. Whites, individuals residing in wealthy and high population density regions were more often admitted to centers performing substantial procedural volume. Among patients undergoing mechanical thrombectomy, Whites were more often treated at substantial volume centers than Hispanics, Blacks or Asians. Though noted correlations may be multi-factorial, socioeconomic factors may predict admission and treatment in high volume procedural centers.

Abstract TMP6: Peri-procedural Complications of Endovascular Treatment for Acute Stroke in SWIFT Trial

Background: Management of patients with ischemic stroke after endovascular treatment requires knowledge of peri-procedural complications. The SWIFT trial compared two devices (Merci and SOLITAIRE) in a randomized, prospective study. We reviewed peri-procedural complications of endovascular treatment and related clinical and technical factors.

Methods: The SWIFT database was searched for major peri-procedural complications defined as: symptomatic intracranial hemorrhage (sICH) within 36 hours, symptomatic subarachnoid hemorrhage (SAH), air emboli, vessel dissection, major groin complications, and emboli to new vascular territories.

Results: Major peri-procedural complications occurred in 18/144 patients (12.5%) at the following rates: sICH (4.9%); SAH (3.5%), air emboli (1.4%), vessel dissection (4.2%), major groin complications (2.8%), and emboli to new vascular territories (0.7%). We did not observe any statistically significant associations of complications with: age (<65 y 13.8% vs. >65 y 11.6%); type of center (academic 9.3% vs non-academic 13.9%); duration of stroke symptoms (<6h 11.1% vs 14.7% >6 h), NIH stroke scale score (NIHSS<20 12% vs. NIHSS >20,13.9%), iv thrombolytics (no iv tPA 10.5% vs iv tPA15.2%), atrial fibrillation (absent 10.1% vs present 14.7%), site of vessel occlusion (ICA 19.2%; MCA 11.5%); rescue therapy administered after endovascular treatment (no rescue 11.9% vs rescue 14.9%); or device (Merci 14.5%; Solitaire 11.2%). Comparing the Merci to the Solitaire retrieval device, we observed the following peri-procedural events:

Conclusion: Detailed knowledge of peri-procedural complications is important for managing stroke patients after endovascular treatment. Fewer endovascular complications were observed after with SOLITAIRE device treatment compared to Merci device treatment, particularly symptomatic cerebral hemorrhage. Device registries will be helpful to gain deeper understanding of rare events.

Mechanical thrombectomy for acute ischemic stroke using the MERCI retriever and penumbra aspiration systems

OBJECTIVE

Intracranial large-vessel ischemia is associated with poor clinical outcome and increased mortality. Early reperfusion of ischemic tissue remains the goal of treatment of stroke. Intravenous tissue plasminogen activator (IV tPA) has been shown to improve clinical outcomes for patients who experience ischemic stroke, but it has been shown to be less efficacious for large-vessel occlusions. Mechanical clot extraction provides a therapeutic option for those who are ineligible for, or who do not respond to, conventional ischemic stroke treatment.

METHODS

We reviewed the initial studies of the Merci Retriever and Penumbra System for mechanical clot extraction. Baseline patient characteristics, as well as revascularization rates and clinical outcome, were examined.

RESULTS

Baseline National Institutes of Health Stroke Scale scores were greater than those observed in previous IV tPA studies, consistent with large-vessel occlusion. Successful recanalization occurred more frequently than with IV tPA and was associated with improved clinical outcome and mortality. Symptomatic intracranial hemorrhage and mortality rates were greater than those seen with IV tPA.

CONCLUSIONS

Mechanical clot extraction can be performed safely in patients with large-vessel occlusions, and successful recanalization resulted in better clinical outcomes than those without. Mechanical thrombectomy provides a therapeutic option for ischemic stroke patients who are ineligible for, or who do not respond to, IV thrombolytics. Further studies, including randomized clinical trials, are needed to validate these findings.

Cerebral arteriovenous malformations: issues of the interplay between stereotactic radiosurgery and endovascular surgical therapy

Intracranial arteriovenous malformations (AVMs) are congenital lesions frequently diagnosed as a result of hemorrhage or other neurological symptoms. Prevention of such devastating neurological injury has promoted a variety of treatment strategies. The rich history of multimodal therapy in the treatment of AVMs includes microsurgery, endovascular embolization, and stereotactic radiosurgery (SRS). This article reviews the biology and natural history of AVMs, as well as their treatment with both SRS and endovascular neurosurgery. It considers various paradigms and goals of endovascular treatment, along with relevant issues such as the features of an AVM to be targeted. Issues of the interplay between SRS and endovascular neurosurgery include the compartments of an embolized AVM to contain within the radiosurgery plan, the radioprotective and radiosensitizing effects of the embolic agent, the durability of embolization, and the sequencing of embolization with respect to the radiosurgical treatment. Published literature on these topics is sparse, and the flimsiness of the data offers limited guidance.

Shape memory alloys: metallurgy, biocompatibility, and biomechanics for neurosurgical applications

SHAPE MEMORY ALLOYS possess distinct dynamic properties with particular applications in neurosurgery. Because of their unique physical characteristics, these materials are finding increasing application where resiliency, conformation, and actuation are needed. Nitinol, the most frequently manufactured shape memory alloy, responds to thermal and mechanical stimuli with remarkable mechanical properties such as shape memory effect, super-elasticity, and high damping capacity. Nitinol has found particular use in the biomedical community because of its excellent fatigue resistance and biocompatibility, with special interest in neurosurgical applications. The properties of nitinol and its diffusionless phase transformations contribute to these unique mechanical capabilities. The features of nitinol, particularly its shape memory effect, super-elasticity, damping capacity, as well as its biocompatibility and biomechanics are discussed herein. Current and future applications of nitinol and other shape memory alloys in endovascular, spinal, and minimally invasive neurosurgery are introduced. An understanding of the metallurgic properties of nitinol provides a foundation for further exploration of its use in neurosurgical implant design.

Surgery of the mind and mood: a mosaic of issues in time and evolution

The prevalence and economic burden of neuropsychiatric disease are enormous. The surgical treatment of these psychiatric disorders, although potentially valuable, remains one of the most controversial subjects in medicine, as its concept and potential reality raises thorny issues of moral, ethical, and socioeconomic consequence. This article traces the roots of concept and surgical efforts in this turbulent area from prehistory to the 21st century. The details of the late 19th and 20th century evolution of approaches to the problem of intractable psychiatric diseases with scrutiny of the persona and contributions of the key individuals Gottlieb Burckhardt, John Fulton, Egas Moniz, Walter Freeman, James Watts, and William Scoville are presented as a foundation for the later, more logically refined approaches of Lars Leksell, Peter Lindstrom, Geoffrey Knight, Jean Talaraich, and Desmond Kelly. These refinements, characterized by progressive minimalism and founded on a better comprehension of underlying pathways of normal function and disease states, have been further explored with recent advances in imaging, which have allowed the emergence of less invasive and technology driven non-ablative surgical directives toward these problematical disorders of mind and mood. The application of therapies based on imaging comprehension of pathway and relay abnormalities, along with explorations of the notion of surgical minimalism, promise to serve as an impetus for revival of an active surgical effort in this key global health and socioeconomic problem. Eventual coupling of cellular and molecular biology and nanotechnology with surgical enterprise is on the horizon.

A novel technique and new grading scale for the embolization of cerebral vascular malformations

OBJECTIVE

Effective transarterial embolization of a dural arteriovenous fistula or pial arteriovenous malformation (AVM) requires penetration of a durable occlusive agent into the fistula or AVM nidus. Cyanoacrylate glue often cannot traverse the tortuous vessels that typically supply such malformations, leading to proximal occlusion and recruitment of collateral flow. Other embolic agents, such as polyvinyl alcohol particles, achieve better penetration, but their effects are short lived, often leading to recanalization. The authors sought to overcome these obstacles by developing a technique to enhance glue penetration into the fistula or AVM nidus itself.

METHODS

After placing a guide catheter in the proximal feeding artery, a microcatheter is advanced coaxially to its limit. As glue is injected through the microcatheter, a column of 5% dextrose in water (D5W) is pushed manually through the guide catheter lumen to propel the glue forward. This technique has been bench tested in a standard flow model of vascular malformations, using a pump capable of delivering various rates of D5W. It has also been validated in treating 17 patients with cerebral dural arteriovenous fistulae or AVMs, with real-time adjustment of D5W flow according to the extent of glue penetration.

RESULTS

In the bench model, the extent of glue penetration, as graded by a new scale of liquid agent embolization proposed by the authors, correlated directly with the rate of D5W flow (P = 0.5, analysis of variance). In vivo, this technique has enhanced the penetration of glue into the fistula or AVM nidus, resulting in longstanding embolization of these malformations.

CONCLUSION

Coaxial injection of D5W through the guide catheter can propel cyanoacrylate glue through tortuous feeding arteries and can enhance its penetration into dural fistulae and AVMs, leading to more effective endovascular treatment of these malformations.

Surgery of the mind and mood: a mosaic of issues in time and evolution

The prevalence and economic burden of neuropsychiatric disease are enormous. The surgical treatment of these psychiatric disorders, although potentially valuable, remains one of the most controversial subjects in medicine, as its concept and potential reality raises thorny issues of moral, ethical, and socioeconomic consequence. This article traces the roots of concept and surgical efforts in this turbulent area from prehistory to the 21st century. The details of the late 19th and 20th century evolution of approaches to the problem of intractable psychiatric diseases with scrutiny of the persona and contributions of the key individuals Gottlieb Burckhardt, John Fulton, Egas Moniz, Walter Freeman, James Watts, and William Scoville are presented as a foundation for the later, more logically refined approaches of Lars Leksell, Peter Lindstrom, Geoffrey Knight, Jean Talaraich, and Desmond Kelly. These refinements, characterized by progressive minimalism and founded on a better comprehension of underlying pathways of normal function and disease states, have been further explored with recent advances in imaging, which have allowed the emergence of less invasive and technology driven non-ablative surgical directives toward these problematical disorders of mind and mood. The application of therapies based on imaging comprehension of pathway and relay abnormalities, along with explorations of the notion of surgical minimalism, promise to serve as an impetus for revival of an active surgical effort in this key global health and socioeconomic problem. Eventual coupling of cellular and molecular biology and nanotechnology with surgical enterprise is on the horizon.

Gunshot wounds to the spine in adolescents

OBJECTIVE

The incidence of spinal instability after penetrating gunshot wounds to the spine in adolescents is unknown. We describe our experience over a 15-year period.

METHODS

Hospital records were reviewed retrospectively. After injury and emergency care, patients were transferred to a rehabilitation facility. Examinations were completed using the American Spinal Injury Association and Frankel scales on admission, discharge, and 6 and 12 months after injury. Severity of injury was described by: 1) degree of neurological damage, 2) degree of preserved neurological function, and 3) presence of instability.

RESULTS

Sixty patients were identified with a mean age 15.6 years (+/- 2.7 yr). Twelve patients had cervical, 31 thoracic, and 17 lumbosacral injuries. No operative treatments were used in their care. Thirty-four patients had complete neurological deficits. Mean acute hospitalization was 21.1 days (+/- 22.8 d), and mean rehabilitation stay was 86.3 days (+/- 48.9 d), for a total hospitalization of 107.4 days (+/- 65.9 d). At 1 year, 19 patients were ambulatory and 53 were autonomous. Despite the presence of bony involvement in all, no evidence of spinal instability was noted on follow-up dynamic imaging. Even in two patients with apparent two-column disruption, no instability was noted. At 1-year follow-up, significant (nonfunctional) improvement was noted in the neurological examination (P < 0.0001). Improvements were most notable in those patients with cervical injuries, followed by thoracic and lumbar injuries.

CONCLUSION

After penetrating gunshot wounds to the spine, patients at 1-year follow-up examinations have evidence of significant, but nonfunctional, improvement. No evidence of spinal instability was noted in this study, and no surgical intervention was required.

Gunshot Wounds to the Spine in Adolescents

OBJECTIVE:

The incidence of spinal instability after penetrating gunshot wounds to the spine in adolescents is unknown. We describe our experience over a 15-year period.

METHODS:

Hospital records were reviewed retrospectively. After injury and emergency care, patients were transferred to a rehabilitation facility. Examinations were completed using the American Spinal Injury Association and Frankel scales on admission, discharge, and 6 and 12 months after injury. Severity of injury was described by: 1) degree of neurological damage, 2) degree of preserved neurological function, and 3) presence of instability.

RESULTS:

Sixty patients were identified with a mean age 15.6 years (± 2.7 yr). Twelve patients had cervical, 31 thoracic, and 17 lumbosacral injuries. No operative treatments were used in their care. Thirty-four patients had complete neurological deficits. Mean acute hospitalization was 21.1 days (± 22.8 d), and mean rehabilitation stay was 86.3 days (± 48.9 d), for a total hospitalization of 107.4 days (± 65.9 d). At 1 year, 19 patients were ambulatory and 53 were autonomous. Despite the presence of bony involvement in all, no evidence of spinal instability was noted on follow-up dynamic imaging. Even in two patients with apparent two-column disruption, no instability was noted. At 1-year follow-up, significant (nonfunctional) improvement was noted in the neurological examination (P &lt; 0.0001). Improvements were most notable in those patients with cervical injuries, followed by thoracic and lumbar injuries.

CONCLUSION:

After penetrating gunshot wounds to the spine, patients at 1-year follow-up examinations have evidence of significant, but nonfunctional, improvement. No evidence of spinal instability was noted in this study, and no surgical intervention was required.

Hypertension, age, and location predict rupture of small intracranial aneurysms

BACKGROUND

Although current guidelines for the management of unruptured intracranial aneurysms (IAs) suggest aneurysms larger than 7 mm should be considered for treatment, a significant number of subarachnoid hemorrhages are caused by IAs 7 mm or smaller. Thus, we sought to identify risk factors associated with the rupture of IAs 7 mm or smaller.

METHODS

We identified 100 patients with subarachnoid hemorrhage resulting from IAs 7 mm or smaller between January 2001 and 2004. Patients were compared with controls (n = 51) with unruptured IAs 7 mm or smaller, diagnosed by conventional angiography or three-dimensional computerized angiography, with respect to aneurysm characteristics (size, location, and age of presentation) and risk factors (hypertension, smoking, cocaine use, and family history).

RESULTS

Hypertensive patients with IAs 7 mm or smaller were 2.6 times more likely to experience rupture (P = 0.01; 95% confidence interval, 1.21-5.53) than patients with normal blood pressure. Posterior circulation aneurysms were 3.5 times more likely to rupture than anterior circulation aneurysms (P = 0.048; 95% confidence interval, 0.95-19.4). After adjustment for location and hypertension, the age of patient on presentation was associated with a trend toward inverse correlation with aneurysmal rupture risk (P = 0.07). Hypertension and posterior location remained significant independent predictors in the logistic regression model.

CONCLUSION

Among patients with small aneurysms (< or = 7 mm), hypertension, relatively young age, and posterior circulation were significant risk factors for rupture. Given the minimal long-term morbidity and mortality of treatment of unruptured aneurysms in large, tertiary medical centers, management of unruptured aneurysms 7 mm or smaller should be governed by factors other than size, specifically age, history of hypertension, and location.

Long-term neurological, visual, and endocrine outcomes following transnasal resection of craniopharyngioma

OBJECT

The authors report on a cohort of patients with craniopharyngioma treated principally through transnasal (TN) resection and followed up for a minimum of 5 years. More specifically, they evaluate the role of the TN approach in the management of craniopharyngioma.

METHODS

Between 1984 and 1994, 68 patients underwent TN resection of craniopharyngiomas at the University of Southern California. The tumor was at least partially cystic in 88% of cases. Four tumors were purely intrasellar, 53 had intra- and suprasellar components, and 11 were exclusively suprasellar. During the same period, 18 patients underwent transcranial (TC) resection of purely suprasellar craniopharyngiomas. Long-term neurological, visual, and endocrine outcomes were reviewed for all patients. In 61 (90%) of 68 patients in the TN group, total resection was achieved, according to 3-month postoperative magnetic resonance images, although four patients suffered a recurrence. Three (43%) of the seven tumors that had been partially resected were enlarged on serial imaging. Fifty-four (87%) of 62 patients with preoperative visual loss experienced improvement in one or both eyes, but two patients (3%) with exclusively suprasellar tumors experienced postoperative visual worsening in one or both eyes. New instances of postoperative endocrinopathy (that is, not present preoperatively) occurred as follows: hypogonadism (eight of 22 cases), growth hormone (GH) deficiency (four of 18 cases), hypothyroidism (11 of 49 cases), hypocortisolemia (nine of 52 cases), and diabetes insipidus (DI; four of 61 cases). One case each of hypocortisolemia and hypothyroidism resolved after surgery. Hyperphagia occurred in 27 (40%) of 68 patients. One patient had short-term memory loss. Postoperative complications included one case of cerebrospinal fluid leak. Among the 18 patients in the TC group, 11 had complete resections. In one case (9%) the tumors recurred. Three (43%) of the seven subtotally resected tumors grew during the follow-up interval. Vision improved in 11 (61%) of 18 cases and worsened in three (17%) as a result of surgery. New instances of postoperative endocrinopathy occurred as follows: hypogonadism (one of six cases), GH deficiency (four of seven cases), hypothyroidism (11 of 14 cases), hypocortisolemia (eight of 15 cases), and DI (nine of 16 cases). No instance of preoperative endocrinopathy was corrected through TC surgery. Four patients (22%) exhibited short-term memory loss and 11 (61%) had hyperphagia after surgery. When compared with those in the TC group, patients in the TN group had shorter hospital stays.

CONCLUSIONS

Use of the TN approach can render good outcomes in properly selected patients with craniopharyngioma, particularly when the tumor is cystic. Even in mostly suprasellar cases, an extended TN approach can afford complete resection. Note that endocrine function often worsens after surgery and that postoperative obesity can be a significant problem.

Neonatal subgaleal hematoma causing brain compression: report of two cases and review of the literature

OBJECTIVE AND IMPORTANCE

Neonatal subgaleal hematomas (SGHs) are infrequent but underdiagnosed collections of blood beneath the galea, often caused by vacuum delivery. With massive bleeding into the subgaleal space, exsanguination and hypovolemic shock can cause death in 20 to 60% of newborn infants. We report the first two known patients with extracranial cerebral compression caused by SGH. Also, the surgical evacuation of neonatal SGH has not been described previously.

CLINICAL PRESENTATION

One patient was a full-term boy who was delivered via vacuum extraction after an uncomplicated pregnancy. Within a few hours, he developed an expanding fluid collection of the scalp and disseminated intravascular coagulation and shock requiring intubation, inotropic support, and blood transfusions. His head circumference grew from 33 cm at birth to 42 cm. He became progressively lethargic and developed posturing movements. Computed tomography of the head revealed a massive SGH causing gross overlapping of the cranial sutures and diffuse cerebral edema. The other patient was a full-term boy delivered via cesarean section after an unsuccessful attempt at vacuum extraction and forceps delivery. The initial head circumference was 34 cm. Within a few hours, he developed an expanding fluid collection of the scalp and became progressively lethargic with posturing. Magnetic resonance imaging of the head revealed a massive SGH with cranial compromise and diffuse cerebral edema.

INTERVENTION

Both children had radiographic features indicative of elevated intracranial pressure as well as neurological decompensation. The first patient was taken to the operating room, and the hematoma was evacuated through a small scalp incision. Initially, approximately 150 ml of blood was removed, and a Jackson-Pratt drain diverted another 200 ml of blood during the next 2 days. The infant made a good recovery. In the second case, the patient remained too unstable for operative intervention and died.

CONCLUSION

Extracranial cerebral compression represents another way by which neonatal SGH may jeopardize the infant's life. Management consists of measures to correct hypovolemic shock and disseminated intravascular coagulation, as well as surgical intervention to control elevated intracranial pressure.

The use of oxidized regenerated cellulose in neurosurgical procedures

The following paper discusses a number of issues relevant to the use of topical hemostatic agents in neurosurgical procedures. We initially describe the basic application of such products and review their relative benefits in neurosurgical interventions, emphasizing the use of oxidized, regenerated cellulose. We then discuss their role in specific operations, such as cortical debridement, cavernous sinus, and other skull base approaches, and aneurysms and arteriovenous malformations of the brain.

Predictive value of serum prolactin levels measured immediately after transsphenoidal surgery

OBJECT

Prolactin-secreting pituitary adenomas may be managed by surgery, medication, radiotherapy, or observation. The authors reviewed a consecutive series of patients who were followed for at least 5 years after surgery to assess the prognostic significance of preoperative factors (tumor size and prolactin level) and an immediate postoperative factor (prolactin level obtained the morning after surgery) on long-term hormonal outcome, thereby clarifying the indications for surgical removal of tumor, the definition of successful treatment outcomes, and the nature of "recurrent" tumors.

METHODS

Between 1979 and 1991, 241 patients with prolactinomas underwent transsphenoidal resection. Nineteen patients were lost to follow-up review, whereas the remaining 222 patients underwent measurement of their prolactin levels on postoperative Day 1 (POD 1), at 6 and 12 weeks, and every 6 months thereafter for a minimum of 5 years. On POD 1, prolactin levels in 133 patients (Group 1) were lower than 10 ng/ml, in 43 patients (Group 2) between 10 and 20 ng/ml, and in 46 patients (Group 3) higher than 20 ng/ml. At 6 and 12 weeks, normal prolactin levels (< or = 20 ng/ml) were measured in 132 (99%) of the 133 patients in Group 1 but only in 32 (74%) of the 43 patients in Group 2. By 5 years postoperatively, normal levels of prolactin were still measured in 130 patients (98%) in Group 1 compared with only five patients (12%) in Group 2. No patient with a prolactin level lower than 3 ng/ml on POD 1 was found to have an elevated hormone level at 5 years. The likelihood of a long-term chemical cure was greater for patients with microadenomas (91% cure rate) than for those with macroadenomas (33%). Preoperative prolactin levels also correlated with hormonal outcome.

CONCLUSIONS

Prolactin levels lower than 10 ng/ml on POD 1 predict a long-term chemical cure in patients with microadenomas (100% cure rate) and those with macroadenomas (93% cure rate). In contrast, a cure is not likely to be obtained in patients with normal levels ranging between 10 and 20 ng/ml on POD 1 if they harbor macroadenomas (0% cure rate). A recurrence reported several years after surgery probably represents the presence of persistent tumor that was not originally removed. If the initial operation was performed by an experienced surgeon, however, reoperation is not likely to yield a chemical cure.

Percutaneous transpedicular polymethylmethacrylate vertebroplasty for the treatment of spinal compression fractures

OBJECTIVE

To assess the safety, feasibility, and clinical outcome of percutaneous transpedicular polymethylmethacrylate vertebroplasty (PTPV) for the treatment of spinal compression fractures causing refractory pain.

METHODS

We retrospectively reviewed a consecutive group of patients undergoing PTPV at our institution between April 1998 and January 2001. Outcome measures included analgesic requirements, ambulatory status, sleep comfort, and overall quality of life 2 weeks after the procedure.

RESULTS

A total of 97 patients (73 women and 24 men) underwent 258 PTPV procedures during 133 treatment sessions. The mean age was 76 years (range, 42-99 yr). The mean duration of follow-up was 14.7 months (range, 2-35 mo). Most of the patients had osteoporotic compression fractures, although some had osteolytic malignancies. Complete follow-up was obtained in 81 patients (84%). Narcotic and analgesic usage decreased in 63% of patients, increased in 7%, and remained the same in 30%. Ambulation and mobility were improved in 51%, worse in 1% and the same in 48%. One-half of the patients were able to sleep more comfortably after the procedure, whereas the other half remained the same. Most patients who reported no change in sleep or ambulation had experienced no impairment of these activities before PTPV. Overall, 74% of patients believed that PTPV significantly enhanced their quality of life and 26% reported no change. No patient was worse after PTPV. One patient with preexisting pneumonia died of respiratory failure after the procedure; another died of an acute stroke weeks later. One patient developed symptomatic pulmonary embolism of cement, and another developed transient quadriceps weakness from radiculopathy. Other complications were minor and infrequent. There were no infections.

CONCLUSION

PTPV provided significant relief in a high percentage of patients with refractory pain. PTPV is a safe and feasible treatment for patients with spinal compression fractures.

Percutaneous carotid angioplasty and stenting with the use of gadolinium in lieu of iodinated contrast medium: technical case report and review of the literature

OBJECTIVE AND IMPORTANCE

We describe a patient who underwent percutaneous transluminal carotid angioplasty and stent placement with the use of intra-arterial gadolinium (Gd-DTPA) instead of iodinated contrast medium. This represents one of the first published reports of the use of Gd-DTPA as an angiographic contrast agent for an interventional neuroradiological procedure.

CLINICAL PRESENTATION

A 75-year-old man with renal insufficiency and multiple comorbidities developed amaurosis fugax. Doppler examination revealed high-grade stenosis of the right internal carotid artery.

INTERVENTION

The patient underwent percutaneous transluminal balloon angioplasty with endovascular stent placement for 95% narrowing of the proximal right internal carotid artery. Because of his impaired renal function, the procedure was performed with the use of Gd-DTPA as the sole contrast agent. Approximately 60 ml of contrast medium (twice the volume typically used for a magnetic resonance imaging study) was used. There were no neurological, renal, or other complications.

CONCLUSION

Intra-arterially administered Gd-DTPA may be substituted for iodinated contrast agents in complex neuroendovascular procedures. This capacity expands the armamentarium for interventional neuroradiological procedures.

Microcatheterization of the cervical epidural space via lumbar puncture: technical note

OBJECTIVE

Deposition of opiates, corticosteroids, or local anesthetics into the epidural space is useful for the management of painful maladies of the cervical and thoracic spine. We describe a novel technique for epidural medication delivery via an angiographic microcatheter inserted at or below the conus and advanced cephalad under fluoroscopic guidance. Unlike commercial kits used by anesthesiologists, this method uses a radiopaque catheter that can be precisely targeted to the levels of interest. The hazards of direct puncture, such as "wet tap" or injury to the cervical cord, are minimized.

METHODS

An 18-gauge Tuohy needle is inserted into the lumbar epidural space. A 2.3-French microcatheter and a 0.018-inch steerable guidewire are then introduced through the lumen of the needle. The catheter is fluoroscopically advanced to the cervical epidural space, where Depo-Medrol (Pharmacia & Upjohn, Kalamazoo, MI) is administered. As the catheter is withdrawn, additional corticosteroid can be delivered to the thoracic epidural space, together with long-acting morphine compounds or local anesthetics. Regional pressures within the epidural space and other physiological parameters can be measured, and the local microenvironment can be sampled.

RESULTS

To date, we have performed 16 procedures for 13 patients. All patients reported improvement, of varying extent and duration. There have been no complications.

CONCLUSION

Our system of accessing the epidural space has many advantages, compared with direct puncture and commercially available kits. It provides a safe means of delivering epidural medication to multiple spinal levels and permits measurement of physiological variables that may be useful in the diagnosis and treatment of cervical and thoracic spine disease.