Diagnostic Accuracy of Somatosensory Evoked Potential Monitoring in Evaluating Neurological Complications During Endovascular Aneurysm Treatment

BACKGROUND

Somatosensory evoked potential (SSEP) monitoring is used extensively for early detection and prevention of neurological complications in patients undergoing many different neurosurgical procedures. However, the predictive ability of SSEP monitoring during endovascular treatment of cerebral aneurysms is not well detailed.

OBJECTIVE

To evaluate the performance of intraoperative SSEP in the prediction postprocedural neurological deficits (PPNDs) after coil embolization of intracranial aneurysms.

METHODS

This population-based cohort study included patients ≥18 years of age undergoing intracranial aneurysm embolization with concurrent SSEP monitoring between January 2006 and August 2012. The ability of SSEP to predict PPNDs was analyzed by multiple regression analyses and assessed by the area under the receiver operating characteristic curve.

RESULTS

In a population of 888 patients, SSEP changes occurred in 8.6% (n = 77). Twenty-eight patients (3.1%) suffered PPNDs. A 50% to 99% loss in SSEP waveform was associated with a 20-fold increase in risk of PPND; a total loss of SSEP waveform, regardless of permanence, was associated with a greater than 200-fold risk of PPND. SSEPs displayed very good predictive ability for PPND, with an area under the receiver operating characteristic curve of 0.84 (95% CI 0.76-0.92).

CONCLUSION

This study supports the predictive ability of SSEPs for the detection of PPNDs. The magnitude and persistence of SSEP changes is clearly associated with the development of PPNDs. The utility of SSEP monitoring in detecting ischemia may provide an opportunity for neurointerventionalists to respond to changes intraoperatively to mitigate the potential for PPNDs.

Long-term outcomes of intradural cervical dorsal root rhizotomy for refractory occipital neuralgia

OBJECT Occipital neuralgia (ON) causes chronic pain in the cutaneous distribution of the greater and lesser occipital nerves. The long-term efficacy of cervical dorsal root rhizotomy (CDR) in the management of ON has not been well described. The authors reviewed their 14-year experience with CDR to assess pain relief and functional outcomes in patients with medically refractory ON. METHODS A retrospective chart review of 75 ON patients who underwent cervical dorsal root rhizotomy, from 1998 to 2012, was performed. Fifty-five patients were included because they met the International Headache Society's (IHS) diagnostic criteria for ON, responded to CT-guided nerve blocks at the C-2 dorsal nerve root, and had at least one follow-up visit. Telephone interviews were additionally used to obtain data on patient satisfaction. RESULTS Forty-two patients (76%) were female, and the average age at surgery was 46 years (range 16-80). Average follow up was 67 months (range 5-150). Etiologies of ON included the following: idiopathic (44%), posttraumatic (27%), postsurgical (22%), post-cerebrovascular accident (4%), postherpetic (2%), and postviral (2%). At last follow-up, 35 patients (64%) reported full pain relief, 11 (20%) partial relief, and 7 (16%) no pain relief. The extent of pain relief after CDR was not significantly associated with ON etiology (p = 0.43). Of 37 patients whose satisfaction-related data were obtained, 25 (68%) reported willingness to undergo repeat surgery for similar pain relief, while 11 (30%) reported no such willingness; a single patient (2%) did not answer this question. Twenty-one individuals (57%) reported that their activity level/functional state improved after surgery, 5 (13%) reported a decline, and 11 (30%) reported no difference. The most common acute postoperative complications were infections in 9% (n = 5) and CSF leaks in 5% (n = 3); chronic complications included neck pain/stiffness in 16% (n = 9) and upper-extremity symptoms in 5% (n = 3) such as trapezius weakness, shoulder pain, and arm paresthesias. CONCLUSIONS Cervical dorsal root rhizotomy provides an efficacious means for pain relief in patients with medically refractory ON. In the appropriately selected patient, it may lead to optimal outcomes with a relatively low risk of complications.

Carotid artery injury during endoscopic endonasal skull base surgery: incidence and outcomes

BACKGROUND

Injury to the internal carotid artery (ICA) during endoscopic endonasal skull base surgery is a feared complication that is not well studied or reported.

OBJECTIVE

To evaluate the incidence, to identify potential risk factors, and to present management strategies and outcomes of ICA injury during endonasal skull base surgery at our institution.

METHODS

We performed a retrospective review of all endoscopic endonasal operations performed at our institution between 1998 and 2011 to examine potential factors predisposing to ICA injury. We also documented the perioperative management and outcomes after injury.

RESULTS

There were 7 ICA injuries encountered in 2015 endonasal skull base surgeries, giving an incidence of 0.3%. Most injuries (5 of 7) involved the left ICA, and the most common diagnosis was chondroid neoplasm (chordoma, chondrosarcoma; 3 of 7 [2% of 142 cases]). Two injuries occurred during 660 pituitary adenoma resections (0.3%). The paraclival ICA segment was the most commonly injured site (5 of 7), and transclival and transpterygoid approaches had a higher incidence of injury, although neither factor reached statistical significance. Four of 7 injured ICAs were sacrificed either intraoperatively or postoperatively. No patient suffered a stroke or neurological deficit. There were no intraoperative mortalities; 1 patient died postoperatively of cardiac ischemia. One of the 3 preserved ICAs developed a pseudoaneurysm over a mean follow-up period of 5 months that was treated endovascularly.

CONCLUSION

ICA injury during endonasal skull base surgery is an infrequent and manageable complication. Preservation of the vessel remains difficult. Chondroid tumors represent a higher risk and should be resected by surgical teams with significant experience.

Endothelin-1 gene polymorphisms influence cerebrospinal fluid endothelin-1 levels following aneurysmal subarachnoid hemorrhage

Aneurysmal subarachnoid hemorrhage is a type of stroke with high morbidity and mortality. Increased endothelin-1 (ET-1) levels have been associated with increased risk of cerebral vasospasm, which is associated with increased morbidity. The purpose of this study was to investigate the relationships between ET-1 genotypes and ET-1 protein levels in cerebrospinal fluid (CSF) measured 72 hr before angiographic vasospasm measurement in subjects at high risk of cerebral vasospasm. Specifically, this study evaluated the differences between variant positive and variant negative groups of nine different ET-1 single-nucleotide polymorphisms (SNPs) in relationship with the ET-1 protein exposure rate. The CSF ET-1 protein levels were quantified using enzyme-linked immunosorbent assay. One functional SNP and eight ET-1 tagging SNPs were selected because they represent genetic variability in the entire ET-1 gene. The variant negative group of SNP rs2070699 was associated with a significantly higher ET-1 exposure rate than the variant positive group (p = 0.004), while the variant positive group of the rs5370 group showed a trend toward association with a higher ET-1 exposure rate (p = 0.051). Other SNPs were not informative. This is the first study to show differences in ET-1 exposure rate 72 hr before angiography in relation to ET-1 genotypes. These exploratory findings need to be replicated in a larger study; if replicated, these differences in genotypes may be a way to inform clinicians of those patients at a higher risk of increased ET-1 protein levels, which may lead to a higher risk of angiographic vasospasm.

Haptoglobin genotype and functional outcome after aneurysmal subarachnoid hemorrhage

OBJECT

Haptoglobin allele heterogeneity has been implicated in differential reactive oxidant inhibition and inflammation. Haptoglobin α2-α2 has a lower affinity for binding hemoglobin, and when bound to hemoglobin, is cleared less easily by the body. The authors hypothesized that haptoglobin α2-α2 genotype should be less protective for downstream injury after aneurysmal subarachnoid hemorrhage (aSAH) and should portend a worse outcome.

METHODS

Patients with Fisher Grade 2 or higher aSAH were enrolled in the study. Genotyping for haptoglobin genotype was performed from blood and/or CSF. Demographic information, medical condition variables, and hospital course were abstracted from the medical record upon enrollment into the study. Outcome data (modified Rankin Scale score, Glasgow Outcome Scale score, and mortality) were collected at 3 months posthemorrhage.

RESULTS

The authors enrolled 193 patients who ranged in age from 18 to 75 years. Only Caucasians were used in this analysis to minimize bias from variable haptoglobin allele frequencies in populations of different ancestral backgrounds. The sample had more women than men (overall mean age 54.45 years). Haptoglobin α2 homozygotes were older than the other individuals in the study sample (57.27 vs 53.2 years, respectively; p = 0.02) and were more likely to have Fisher Grade 3 SAH (p = 0.02). Haptoglobin α2-α2 genotype, along with Fisher grade and Hunt and Hess grade, was associated with a worse 3-month outcome compared to those with the haptoglobin α1-α1 genotype according to modified Rankin Scale score after controlling for covariates (OR 4.138, p = 0.0463).

CONCLUSIONS

Patients with aSAH who carry the haptoglobin α2-α2 genotype had a worse outcome. Interestingly, the presence of a single α-2 allele was associated with worse outcome, suggesting that the haptoglobin α-2 protein may play a role in the pathology of brain injury following aSAH, although the mechanism for this finding requires further research. The haptoglobin genotype may provide additional information on individual risk of secondary injury and recovery to guide care focused on improving outcomes.

Abstract TP14: Simultaneous Endovenous Hypothermia and Intra-Arterial Thrombectomy for Acute Ischemic Stroke is Safe, Feasible and Does Not Require General Anesthesia

Background: Hypothermia is a promising neuroprotectant. Amelioration of reperfusion injury after recanalization is a potential benefit. Due to easy access to the femoral vein, endovenous hypothermia can be combined with intra-arterial therapy. Hypothermia and shivering control is possible without mechanical ventilation, deep sedation or paralytic agents.

Methods: Consecutive patients with acute ischemic stroke and receiving intra-arterial therapy were studied. An arterial sheath and an endovenous hypothermia catheter were placed into the femoral artery and vein. Hypothermia induction was performed with cold saline infusion. Goal temperature prior to recanalization was 35° or lower. Hypothermia was continued to a goal of 32° for 24 hrs. Controlled rewarming at 0.2°/hr was carried out. Shivering was controlled with skin counter warming, magnesium, dexmedetomidine, and meperidine. The BSAS scale was used to monitor shivering.

Results: A total of 10 patients were studied, five women. Two patients with brainstem infarction were intubated, eight recieved sedation. Median age was 65 (range 49 - 80), NIHSS 16 (12 - 27), time from last known well 4 hrs (1 - 10) and ASPECTS 7 (6 - 10). Median door to venous needle time was 37 minutes (26 - 67) and arterial 40 minutes (30 - 70). Median time to reach 35° was 23 minutes (13 - 45). Eight patients reached 35° prior to recanalization. Median time to reach 32° was 171 minutes (122 - 235). Median BSAS was 1 (1-2). Median dose of dexmedetomidine infusion was 0.5 mcg/kg (0.2 - 0.8) meperidine 25mg (0 - 75) and magnesium 4gr (4-6). Two patients were treated for pneumonia prior to discharge. One DVT and one PE were diagnosed. No groin complications were recorded. Three patients died, two after withdrawal of care. Five patients were discharged to a rehabilitation facility and two to a skilled nursing facility.

Conclusions: Combined endovenous hypothermia and intra-arterial therapy for acute ischemic stroke is feasible. In non-intubated patients shivering is well controlled and does not necessitate deep sedation or paralytic agents. Hypothermia catheter insertion does not delay intra-arterial recanalization. These data support the planning of a phase 2 trial to assess safety and optimum temperature goals.

Stereotactic radiosurgery with or without embolization for intracranial dural arteriovenous fistulas

Treatment options for symptomatic dural arteriovenous fistulas (DAVFs) include surgery, embolization and stereotactic radiosurgery (SRS). We reviewed our DAVF experience at the University of Pittsburgh and assessed the role of SRS. We evaluated 40 consecutive patients who underwent Gamma Knife SRS for 44 DAVFs. Twenty-eight patients had upfront SRS before or after embolization performed at our institution, and 12 patients underwent delayed SRS for recurrent or residual DAVFs after initial embolization. The median SRS target volume was 2.0 cm3, and the median marginal dose was 21.0 Gy. At a median follow-up of 45 months (range, 23-116 months), a total of 28 patients with 32 DAVFs had obliteration. The obliteration rate was 83% for patients who had upfront SRS and embolization. The obliteration rate was lower (67%) for patients managed with SRS alone. The obliteration rate was 71% for patients who had delayed SRS for recurrent or residual DAVFs following prior embolization. In our experience cavernous/carotid fistulas were associated with higher rates of obliteration and symptomatic improvement compared to transverse/sigmoid sinus region fistulas. Our experience suggests that successful DAVF obliteration is possible in most patients with upfront SRS in conjunction with embolization. SRS alone is an effective treatment for selected patients with a small-volume, low-risk DAVF.

Early Postmarket Results After Treatment of Intracranial Aneurysms With the Pipeline Embolization Device

BACKGROUND:

The Pipeline embolization device (PED) is the latest technology available for intracranial aneurysm treatment.

OBJECTIVE:

To report early postmarket results with the PED.

METHODS:

This study was a prospective registry of patients treated with PEDs at 7 American neurosurgical centers subsequent to Food and Drug Administration approval of this device. Data collected included clinical presentation, aneurysm characteristics, treatment details, and periprocedural events. Follow-up data included degree of aneurysm occlusion and delayed (> 30 days after the procedure) complications.

RESULTS:

Sixty-two PED procedures were performed to treat 58 aneurysms in 56 patients. Thirty-seven of the aneurysms (64%) treated were located from the cavernous to the superior hypophyseal artery segment of the internal carotid artery; 22% were distal to that segment, and 14% were in the vertebrobasilar system. A total of 123 PEDs were deployed with an average of 2 implanted per aneurysm treated. Six devices were incompletely deployed; in these cases, rescue balloon angioplasty was required. Six periprocedural (during the procedure/within 30 days after the procedure) thromboembolic events occurred, of which 5 were in patients with vertebrobasilar aneurysms. There were 4 fatal postprocedural hemorrhages (from 2 giant basilar trunk and 2 large ophthalmic artery aneurysms). The major complication rate (permanent disability/death resulting from perioperative/delayed complication) was 8.5%. Among 19 patients with 3-month follow-up angiography, 68% (13 patients) had complete aneurysm occlusion. Two patients presented with delayed flow-limiting in-stent stenosis that was successfully treated with angioplasty.

CONCLUSION:

Unlike conventional coil embolization, aneurysm occlusion with PED is not immediate. Early complications include both thromboembolic and hemorrhagic events and appear to be significantly more frequent in association with treatment of vertebrobasilar aneurysms.

Abstract 136: Treatment of Basilar Artery Occlusion Without Time Constraints: Clinical outcomes, safety and predictors of favorable results

Background: Because acute stroke due to basilar artery occlusion (BAO) without recanalization (spontaneous or treated) carries a poor prognosis, recanalization treatment is increasingly initiated beyond conventional time windows. We report our experience with endovascular treatment for this condition when patients are selected without regards to time window considerations.

Methods: A retrospective review of a prospectively acquired database comprising 667 patients treated with endovascular therapy for acute stroke due to large vessel intracranial occlusions from 2000 to date. All patients presenting with BAO were included. Selection of patients occurred at the discretion of the treating stroke neurologist not necessarily based on time but based on clinical and imaging characteristics that led to the belief in a reasonable chance of a good outcome. Successful recanalization was expressed as Thrombolysis in Myocardial Infarction (TIMI) score ≥ 2. Favorable outcomes were considered 3 month modified Rankin Score (mRS) ≤ 2. Any parenchymal hematoma (PH) was considered symptomatic.

Results: We identified 85 patients. Median age: 63. Median admission NIHSS: 18 (IQR 11-29). Male sex: 57.6%. Median time from last seen well (TLSW) to groin puncture: 774 min (12.9 hrs) (IQR 324min-2262min). Median procedure duration: 105.5 min (IQR 67min-145min). 18% of patients received IV tPA. TIMI 2-3 recanalization occurred in 87% of patients treated. Favorable outcomes were noted in 34% of patients. mRS of 3 was achieved in 9.4%. Mortality was 46%. PH was noted in 8.2% of patients. Treatment modalities included IA lytics (56.4%), MERCI device (39%), Penumbra (6%), Manual Aspiratoin Thrombectomy (27%), Stenting (42%), Angioplasty (46%). In 76.4% of patients the procedure was carried out in intubated state. In multivariate analysis, age (OR 0.94, P=0.007, 95% CI 0.89-0.98), successful recanalization (OR 16, P=0.027, 95% CI 1.38-197.56) and admission glucose (OR 0.98, P=0.033, 95%CI 0.97-0.99) were found to be significantly associated with favorable outcomes. Of note TLSW to treatment initiation was not found in univariate or multivariate analyses to be significantly associated with favorable outcomes.

Conclusions: This single center experience indicates that endovascular treatment in selected patients with BAO without time window considerations is associated with similar rates of symptomatic hemorrhage (SICH) and rates of favorable outcomes compared to available literature data where selection is based on strict time windows. The role of time as selection criteria for treatment of BAO should be clarified by future prospective trials.

Is a head CT necessary after uncomplicated coiling of unruptured intracranial aneuryms?

In this study, we sought to determine whether routine head computed tomographies (CTs) after uncomplicated coil embolization of intracranial aneurysms can add any significant clinical value.

METHODS

We retrospectively reviewed the medical records of 139 patients with unruptured aneurysms who underwent 150 elective coiling procedures between January 2008 and June 2010. A total of 6 head CTs were obtained emergently after intraprocedural complications and 122 head CTs were obtained routinely after uncomplicated coil embolization of intracranial aneurysms.

RESULTS

The 122 head CTs that were obtained routinely after uncomplicated coil embolization of unruptured intracranial aneurysms did not show any acute or subacute changes.

CONCLUSION

A head CT after uncomplicated coil embolization of an intracranial aneurysm does not add any significant clinical value and should not be ordered routinely.

Microvascular decompression for hemifacial spasm: evaluating outcome prognosticators including the value of intraoperative lateral spread response monitoring and clinical characteristics in 293 patients

Hemifacial spasm is a socially disabling condition that manifests as intermittent involuntary twitching of the eyelid and progresses to muscle contractions of the entire hemiface. Patients receiving microvascular decompression of the facial nerve demonstrate an abnormal lateral spread response (LSR) in peripheral branches during facial electromyography. The authors retrospectively evaluate the prognostic value of preoperative clinical characteristics and the efficacy of intraoperative monitoring in predicting short- and long-term relief after microvascular decompression for hemifacial spasm. Microvascular decompression was performed in 293 patients with hemifacial spasm, and LSR was recorded during intraoperative facial electromyography monitoring. In 259 (87.7%) of the 293 patients, the LSR was attainable. Patient outcome was evaluated on the basis of whether the LSR disappeared or persisted after decompression. The mean follow-up period was 54.5 months (range, 9-102 months). A total of 88.0% of patients experienced immediate postoperative relief of spasm; 90.8% had relief at discharge, and 92.3% had relief at follow-up. Preoperative facial weakness and platysmal spasm correlated with persistent postoperative spasm, with similar trends at follow-up. In 207 patients, the LSR disappeared intraoperatively after decompression (group I), and in the remaining 52 patients, the LSR persisted intraoperatively despite decompression (group II). There was a significant difference in spasm relief between both groups within 24 hours of surgery (94.7% vs. 67.3%) (P < 0.0001) and at discharge (94.2% vs. 76.9%) (P = 0.001), but not at follow-up (93.3% vs. 94.4%) (P = 1.000). Multivariate logistic regression analysis demonstrated independent predictability of residual LSR for present spasm within 24 hours of surgery and at discharge but not at follow-up. Facial electromyography monitoring of the LSR during microvascular decompression is an effective tool in ensuring a complete decompression with long-lasting effects. Although LSR results predict short-term outcomes, long-term outcomes are not as reliant on LSR activity.

Role of endothelin-1 in human aneurysmal subarachnoid hemorrhage: associations with vasospasm and delayed cerebral ischemia

BACKGROUND

Endothelin-1 (ET-1) is a potent vasoconstrictor implicated in the pathogenesis of vasospasm and delayed cerebral ischemia (DCI) in aneurysmal subarachnoid hemorrhage (aSAH) patients. The aim of this study was to investigate the relationship between cerebrospinal fluid (CSF) ET-1 levels and angiographic vasospasm and DCI.

METHODS

Patients with aSAH were consented (n = 106). Cerebral vasospasm was determined by angiography. DCI was determined by transcranial Doppler (TCD) results and/or angiogram results with corresponding clinical deterioration. CSF ET-1 levels over 14 days after the initial insult was quantified by ELISA. ET-1 analysis included a group-based trajectory analysis and ET-1 exposure rate during 24, 48, and 72 h prior to, as well as 72 h post angiography, or clinical deterioration.

RESULTS

Trajectory analysis revealed two distinct groups of subjects with 56% of patients in the low ET-1 trajectory group (mean at day 1 = 0.31 pg/ml; SE = 0.04; mean at day 14 = 0.41 pg/ml; SE = 0.15) and 44% of patients in the high ET-1 trajectory group (mean at day 1 = 0.65 pg/ml; SE = 0.08; mean at day 14 = 0.61 pg/ml; SE = 0.06). Furthermore, we observed that ET-1 exposure rate 72 h before angiography and clinical spasm was a significant predictor of both angiographic vasospasm and DCI, whereas, ET-1 exposure after angiography and clinical spasm was not associated with either angiographic vasospasm or DCI.

CONCLUSION

Based on these results we conclude that ET-1 concentrations are elevated in a sub-group of patients and that the acute (72 h prior to angiography and clinical neurological deterioration), but not chronic, elevations in CSF ET-1 concentrations are indicative of the pathogenic alterations of vasospasm and DCI in aSAH patients.

Stereotactic radiosurgery with or without embolization for intracranial dural arteriovenous fistulas

BACKGROUND

Treatment options for dural arteriovenous fistulas (DAVFs) have expanded with the application of stereotactic radiosurgery (SRS).

OBJECTIVE

To assess the role of SRS with or without embolization, we reviewed our entire DAVF experience.

METHODS

Between 1991 and 2006, 40 patients with 44 DAVFs underwent Gamma knife SRS. Twenty-eight patients had upfront SRS before or after embolization and 12 patients underwent delayed SRS for recurrent or residual DAVFs after initial embolization. The median patient age was 60 years (range, 29-90). DAVFs were diagnosed in 7 patients after they sustained an intracranial hemorrhage. The median SRS target volume was 2.0 mL (range, 0.2-8.2 mL) and the median marginal dose was 21.0 Gy (range, 15-25 Gy).

RESULTS

At a median follow-up of 45 months (range, 23-116 mo), a total of 28 patients (harboring 32 DAVFs) had obliteration confirmed by imaging. We found a 83% obliteration rate in patients who had upfront SRS with embolization and a 67% obliteration rate in patients who only had SRS. One patient died of an intracerebral hemorrhage 2 months after SRS. Cavernous carotid fistulas were associated with higher rates of occlusion (P = .012) and symptom improvement (P = .010) than were transverse-sigmoid sinus-related fistulas.

CONCLUSION

When upfront SRS is possible in conjunction with embolization, successful DAVF obliteration is possible in most patients, especially those with carotid cavernous fistulas. SRS should target the entire fistula regardless of whether it precedes or follows embolization. In selected patients with a small-volume, low-risk DAVF, SRS alone is an effective treatment option in most patients.

Endovascular Treatment of Tandem Extracranial/Intracranial Anterior Circulation Occlusions

Background and Purpose—

Acute ischemic stroke due to tandem occlusions of the extracranial internal carotid artery and intracranial arteries has a poor natural history. We aimed to evaluate our single-center experience with endovascular treatment of this unique stroke population.

Methods—

Consecutive patients with tandem occlusions of the internal carotid artery origin and an intracranial artery (ie, internal carotid artery terminus, M1 middle cerebral artery, or M2 middle cerebral artery) were studied retrospectively. Treatment consisted of proximal revascularization with angioplasty and stenting followed by intracranial intervention. Endpoints were recanalization of both extracranial and intracranial vessels (Thrombolysis In Myocardial Ischemia ≥2), parenchymal hematoma, and good clinical outcome (modified Rankin Scale ≤2) at 3 months.

Results—

We identified 77 patients with tandem occlusions. Recanalization occurred in 58 cases (75.3%) and parenchymal hematoma occurred in 8 cases (10.4%). Distal embolization occurred in 3 cases (3.9%). In 18 of 77 patients (23.4%), distal (ie, intracranial) recanalization was observed after proximal recanalization, obviating the need for distal intervention. Good clinical outcomes were achieved in 32 patients (41.6%). In multivariate analysis, Thrombolysis In Myocardial Ischemia ≥2 recanalization, baseline National Institutes of Health Stroke Scale score, baseline Alberta Stroke Programme Early CT score, and age were significantly associated with good outcome.

Conclusions—

Endovascular therapy of tandem occlusions using extracranial internal carotid artery revascularization as the first step is technically feasible, has a high recanalization rate, and results in an acceptable rate of good clinical outcome. Future randomized, prospective studies should clarify the role of this approach.

Endoscopic endonasal skull base surgery: analysis of complications in the authors' initial 800 patients

Object

The development of endoscopic endonasal approaches, albeit in the early stages, represents part of the continuous evolution of skull base surgery. During this early period, it is important to determine the safety of these approaches by analyzing surgical complications to identify and eliminate their causes.

Methods

The authors reviewed all perioperative complications associated with endoscopic endonasal skull base surgeries performed between July 1998 and June 2007 at the University of Pittsburgh Medical Center.

Results

This study includes the data for the authors' first 800 patients, comprising 399 male (49.9%) and 401 female (50.1%) patients with a mean age of 49.21 years (range 3–96 years). Pituitary adenomas (39.1%) and meningiomas (11.8%) were the 2 most common pathologies. A postoperative CSF leak represented the most common complication, occurring in 15.9% of the patients. All patients with a postoperative CSF leak were successfully treated with a lumbar drain and/or another endoscopic approach, except for 1 patient who required a transcranial repair. The incidence of postoperative CSF leaks decreased significantly with the adoption of vascularized tissue for reconstruction of the skull base (< 6%). Transient neurological deficits occurred in 20 patients (2.5%) and permanent neurological deficits in 14 patients (1.8%). Intracranial infection and systemic complications were encountered and successfully treated in 13 (1.6%) and 17 (2.1%) patients, respectively. Seven patients died during the 30-day perioperative period, 6 of systemic illness and 1 of infection (overall mortality 0.9%).

Conclusions

Endoscopic endonasal skull base surgery provides a viable median corridor based on anatomical landmarks and is customized according to the specific pathological process. This corridor should be considered as the sole access or may be combined with traditional approaches. With the incremental acquisition of skills and experience, endoscopic endonasal approaches have an acceptable safety profile in select patients presenting with various skull base pathologies.

Endovascular therapy for cardiac catheterization associated strokes

BACKGROUND

Stroke is one of the most feared complications after cardiac catheterization. Endovascular treatment combining mechanical and pharmacological therapy has been reported as an effective treatment option in selected patients with acute stroke due to large-vessel occlusion. Little is known about safety and clinical outcome when this approach is utilized in cardiac catheterization associated strokes.

METHODS AND RESULTS

We analyzed clinical and radiological characteristics and outcomes in the endovascular acute stroke treatment databases from two University Hospitals from July 2006 to December 2008 (Cleveland Clinic Foundation) and September 1999 and December 2008 (UPMC Presbyterian hospital), respectively. Of a total of 419 acute stroke interventions, 14 (3.34%) were identified as strokes during or immediately after cardiac catheterization. The mean age was 71 ± 7 years; eight were women (57.1%). Mean National Institute of Health Stroke Scale was 17 (±7.6). Four patients underwent intravenous thrombolysis followed by intraarterial intervention. Median time to treatment was 240 minutes from last time seen normal (range 66-1,365 minutes). Seven patients (50%) had a favorable outcome (modified Rankin Scale [mRS]≤ 2). In-patient mortality was 42%.

CONCLUSION

In acute strokes following cardiac catheterization, multimodal endovascular therapy is safe and feasible and despite a high mortality is associated with a higher than expected rate of favorable outcomes compared to the natural history of the disease. Despite a significant proportion of patients developing symptoms in hospitals where neurointerventions are available, the median time to treatment was longer than expected. Future efforts should focus on faster implementation of recanalization therapies for this form of acute stroke.

Intracranial angiomatoid fibrous histiocytoma presenting as recurrent multifocal intraparenchymal hemorrhage

Angiomatoid fibrous histiocytoma (AFH) is a rare soft-tissue neoplasm that most commonly appears in the limbs, typically affecting children and young adults. The tumor has a propensity for local recurrence and recurrent hemorrhage but rarely for remote metastasis. To date, only 2 reports have documented an intracranial occurrence of the tumor (1 of which was believed to be metastatic disease). This is the second report of primary intracranial AFH. Additionally, hemorrhage from an intracranial AFH lesion has yet to be reported, and little is known about the radiographic characteristics and biological behavior of these lesions. In this report, the authors describe the case of a patient with recurrent hemorrhage due to primary multifocal intracranial AFH. Initially misdiagnosed as a cavernous malformation and then an unusual meningioma, the tumor was finally correctly identified when there was a large enough intact resection specimen to reveal the characteristic histological pattern. The diagnosis was confirmed using immunohistochemical and molecular studies.

Minimal-access technique for distal catheter insertion during ventricular peritoneal shunt procedures: a review of 100 cases

The authors report the safety and efficacy of using a percutaneous minimal-access insertion technique for distal shunt catheter placement in 100 cases. From June 2007 to March 2008, they attempted 100 minimal-access insertions of distal shunt catheters in 91 patients who required ventriculoperitoneal shunting. Using the minimal-access approach, they avoided utilizing laparoscopic assistance or a mini-laparotomy in 91% of the cases. There were no bowel injuries or misplaced distal catheters. Additional outcomes in terms of operative times, cases that required conversion to open or laparoscopically assisted implantation, and infection rates are presented. They conclude that intraperitoneal shunt catheter placement can be safely and effectively accomplished using a simplified percutaneous minimal-access insertion method that does not require direct laparoscopic visualization.

Rapid, simultaneous quantitation of mono and dioxygenated metabolites of arachidonic acid in human CSF and rat brain

Currently, there are few biomarkers to predict the risk of symptomatic cerebral vasospasm (SV) in subarachnoid hemorrhage (SAH) patients. Mono and dioxygenated arachidonic acid metabolites, involved in the pathogenesis of ischemic injury, may serve as indicators of SV. This study developed a quantitative UPLC-MS/MS method to simultaneously measure hydroxyeicosatetraenoic acid (HETE), dihydroxyeicosatrienoic acid (DiHETrE), and epoxyeicosatrienoic acid (EET) metabolites of arachidonic acid in cerebrospinal fluid (CSF) samples of SAH patients. Additionally, we determined the recovery of these metabolites from polyvinylchloride (PVC) bags used for CSF collection. Linear calibration curves ranging from 0.208 to 33.3 ng/ml were validated. The inter-day and intra-day variance was less than 15% at most concentrations with extraction efficiency greater than 73%. The matrix did not affect the reproducibility and reliability of the assay. In CSF samples, peak concentrations of 8,9-DiHETrE, 20-HETE, 15-HETE, and 12-HETE ranged from 0.293 to 24.9 ng/ml. In rat brain cortical tissue samples, concentrations of 20-, 15-, 12-HETE, 8,9-EET, and 14,15-, 11,12-DiHETrE ranged from 0.57 to 23.99 pmol/g wet tissue. In rat cortical microsomal incubates, all 10 metabolites were measured with formation rates ranging from 0.03 to 7.77 pmol/mg/min. Furthermore, 12-HETE and EET metabolites were significantly altered by contact with PVC bags at all time points evaluated. These data demonstrate that the simultaneous measurement of these compounds in human CSF and rat brain can be achieved with a UPLC-MS/MS system and that this method is necessary for evaluation of these metabolites as potential quantitative biomarkers in future clinical trials.

Intracranial arterialized venous angioma: case report with new insights from functional brain MRI

We present the case of a 58-year-old man who suffered a left thalamic intracerebral hemorrhage. Brain magnetic resonance imaging (MRI) revealed an incidental venous angioma in the left frontal lobe. Further elucidated by cerebral angiography and functional MRI, this venous angioma exhibited arteriovenous shunting. The arterialized venous angioma represents an uncommon, "mixed" intracranial vascular lesion whose natural history remains unknown.

Elevated cardiac troponin I and relationship to persistence of electrocardiographic and echocardiographic abnormalities after aneurysmal subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Cardiac injury persistence after aneurysmal subarachnoid hemorrhage (aSAH) is not well described. We hypothesized that post-aSAH cardiac injury, detected by elevated cardiac troponin I (cTnI), is related to aSAH severity and associated with electrocardiographic and structural echocardiographic abnormalities that are persistent.

METHODS

Prospective longitudinal study was conducted of patients with aSAH with Fisher grade >or=2 and/or Hunt/Hess grade >or=3. Serum cTnI was collected on Days 1 to 5; cohort dichotomized into peak cTnI >or=0.3 ng/mL (elevated) or cTnI <0.3 ng/mL. Relationships among cTnI and aSAH severity, 12-lead electrocardiography early (<or=4 days) and late (>or=7 days), Holter monitoring on Days 1 to 5, and transthoracic echocardiogram (left ventricular ejection fraction and regional wall motion abnormalities) early (Days 0 to 5) and late (Days 5 to 12) were evaluated.

RESULTS

Of 204 subjects, 31% had cTnI >or=0.3 ng/mL. cTnI >or=0.3 ng/mL was incrementally related to aSAH severity by admission symptoms (Hunt/Hess P=0.001) and blood load (Fisher P=0.028). More patients with cTnI >or=0.3 ng/mL had prolonged QTc on early (63% versus 30%, P<0.0001) and late electrocardiography (24% versus 7%, P=0.024). On Holter monitoring, more patients with cTnI >or=0.3 ng/mL had ventricular tachycardia/fibrillation (22% versus 9%, P=0.018) but not atrial fibrillation/flutter (P=0.241). Cardiac troponin I >or=0.3 ng/mL was associated with both early ejection fraction <50% (44% versus 5%, P<0.0001) and regional wall motion abnormalities (44% versus 4%, P<0.0001). Regional wall motion abnormalities predominated in basal and midventricular segments and persisted to some degree in 73% of patients affected, whereas ejection fraction <50% persisted in 59% of patients affected.

CONCLUSIONS

Cardiac injury is incrementally worse with increasing aSAH severity and associated with persistent QTc prolongation and ventricular arrhythmias. Regional wall motion abnormalities and depressed ejection fraction persist to some degree in the majority of those affected.

PICA origin aneurysm diagnosed 27 years after microvascular decompression of cranial nerve VII

The authors report a case of a posterior inferior cerebellar artery origin aneurysm causing brainstem compression and swallowing difficulty. The patient had an ipsilateral microvascular decompression of cranial nerve VII for hemifacial spasm 27 years prior to the discovery of the aneurysm. The aneurysm was successfully treated endovascularly. A discussion of possible etiologies of the aneurysm's formation is presented.

Clinical and angiographic outcome after endovascular management of giant intracranial aneurysms

OBJECTIVE

Giant (>or=25 mm) intracranial aneurysms (IA) have an extremely poor natural history and continue to confound modern techniques for management. Currently, there is a dearth of large series examining endovascular treatment of giant IAs only.

METHODS

We reviewed long-term clinical and radiological outcome from a series of 39 consecutive giant IAs treated with endovascular repair in 38 patients at 2 tertiary referral centers. Data were evaluated in 3 ways: on a per-treatment session basis for each aneurysm, at 30 days after each patient's final treatment, and at the last known follow-up examination.

RESULTS

Ten (26%) aneurysms were ruptured. At the last angiographic follow-up examination (21.5 +/- 22.9 months), 95% or higher and 100% occlusion rates were documented in 64 and 36% of aneurysms, respectively, with parent vessel preservation maintained in 74%. Stents were required in 25 aneurysms. Twenty percent of treatment sessions resulted in permanent morbidity, and death within 30 days occurred after 8% of treatment sessions. On average, 1.9 +/- 1.1 sessions were required to treat each aneurysm, with a resulting cumulative per-patient mortality of 16% and morbidity of 32%. At the last known clinical follow-up examination (mean, 24.8 +/- 24.8 months), 24 (63%) patients had Glasgow Outcome Scale scores of 4 or 5 ("good" or "excellent"), 10 patients had worsened neurological function from baseline (26% morbidity), and 11 had died (29% mortality).

CONCLUSION

We present what is to our knowledge the largest series to date evaluating outcome after consecutive giant IAs treated with endovascular repair. Giant IAs carry a high risk for surgical or endovascular intervention. We hope critical and honest evaluation of treatment results will ensure continued improvement in patient care.

Relation of elevation in cardiac troponin I to clinical severity, cardiac dysfunction, and pulmonary congestion in patients with subarachnoid hemorrhage

An increase in cardiac troponin I (cTnI) occurs often after aneurysmal subarachnoid hemorrhage (SAH), but its significance is not well understood. One hundred three patients with SAH were prospectively evaluated in the SAHMII Study to determine the relations of cTnI to clinical severity, systolic and diastolic cardiac function, pulmonary congestion, and length of intensive care unit stay. Echocardiographic ejection fraction, wall motion score, mitral inflow early diastolic (E) and mitral annular early (E') velocities were assessed. Thirty patients (29%) had mildly positive cTnI (0.1 to 1.0 ng/ml), 24 (23%) had highly positive cTnI (>1.0 ng/ml), and 49 (48%) had negative cTnI (<0.1 ng/ml). Highly positive cTnI was associated with worse neurologic disease, longer intensive care unit stay, and slight depression of ejection fraction (51 +/- 11% [p <0.05] vs 59 +/- 8% and 63 +/- 6% in mildly positive or negative cTnI groups, respectively). Highly positive cTnI was also associated with abnormal wall motion acutely (>1.31 ng/ml; 76% sensitivity, 91% specificity), which typically resolved within 5 to 10 days. Both mildly or highly positive cTnI were associated with acute diastolic dysfunction, with E/E' of 17 +/- 6 and 16 +/- 6 (both p <0.05) vs 13 +/- 4 in patients with negative cTnI. Prevalences of pulmonary congestion were 79% (p <0.05) in patients with highly positive cTnI, 53% (p <0.05) in patients with mildly positive cTnI, and 29% in cTnI-negative patients. In conclusion, highly positive cTnI with SAH was associated with clinical neurologic severity, systolic and diastolic cardiac dysfunction, pulmonary congestion, and longer intensive care unit stay. Even mild increases in cTnI were associated with diastolic dysfunction and pulmonary congestion.

APOE genotype and functional outcome following aneurysmal subarachnoid hemorrhage

Apolipoprotein E (apoE), the major apolipoprotein in the central nervous system, has been shown to influence neurologic disease progression and response to neurologic injury in a gene-specific manner. Presence of the APOE4 allele is associated with poorer response to traumatic brain injury and ischemic stroke, but the association between APOE genotype and outcome following aneurysmal subarachnoid hemorrhage (SAH) remains unclear. The purpose of this project was to investigate the association between APOE genotype and outcome after SAH. We also explored the association of APOE4 genotype and cerebral vasospasm (CV) presence in a subsample of our population with available angiographic data. A sample of 206 aneurysmal SAH participants had APOE genotyping performed, Glasgow outcome scores (GOS) and modified Rankin scores (MRS) collected at 3 and 6 months after aneurysm rupture. No significant association was found between the presence of the APOE4 genotype and functional outcomes controlling for age, race, size of hemorrhage (Fisher grade), and severity of injury (Hunt & Hess grade). However when controlling for CV and the covariates listed above, individuals with the APOE4 allele had worse functional outcomes at both time points. The presence of the APOE2 allele was not associated with functional outcomes even when considering presence of CV. There was no difference in mortality associated with APOE4 presence, APOE2 presence, or presence of CV. These findings suggest APOE4 allele is associated with poor outcome after aneurysmal SAH.

Anatomic results and complications of stent-assisted coil embolization of intracranial aneurysms

SUMMARY

The purpose of this study was to evaluate and report our anatomic results and complications associated with stent-assisted coil embolization of intracranial aneurysms using the Neuroform stent. From September 2003 to August 2007, 127 consecutive patients (ruptured 50, 39.4%; unruptured 77, 60.6%) underwent 129 stent-assisted coil embolization procedures to treat 136 aneurysms at our institution. Anatomic results at follow-up, procedure-related complications, and morbidity/mortality were retrospectively reviewed. Stent deployment was successful in 128 out of 129 procedures (99.2%). Forty-seven patients presented with 53 procedure-related complications (37.0%, 47/127). Thromboembolic events (n=17, 13.4%) were the most common complications, followed by intraoperative rupture (n=8, 6.3%), coil herniation (n=5, 3.9%), and postoperative rupture (n=4, 3.1%). For thromboembolic events, acute intra-procedural instent thromboses were observed in two patients and subacute or delayed in-stent thromboses in three patients. Overall mortality rate was 16.5% (21/127) and procedure-related morbidity and mortality rates were 5.5% (7/127) and 8.7% (11/127) retrospectively. Patients with poor grade subarachnoid hemorrhage (Hunt and Hess grade IV or V; 25/127, 19.7%) exhibited 56% (14/25) overall mortality rate and 24% (6/25) procedure-related mortality rate. Immediate angiographic results showed complete occlusion in 31.7% of aneurysms, near-complete occlusion in 45.5%, and partial occlusion in 22.8%. Sixty nine patients in 70 procedures with 77 aneurysms underwent angiographic followup at six months or later. Mean follow-up period was 13.7 months (6 to 45 months). Complete occlusion was observed in 57 aneurysms (74.0%) and significant in-stent stenosis was not found. Thromboembolism and intra/postoperative aneurysm ruptures were the most common complications and the main causes of procedure-related morbidity and mortality. Patients with poor grade subarachnoid hemorrhage showed poor clinical outcomes. Since most complications were induced by stent manipulation and deployment, it is mandatory to utilize these devices selectively and cautiously. While the follow- up angiographic results are promising, further studies are essential to evaluate safety, efficacy, and durability of the Neuroform stent.

Extensive brainstem ischemia on neuroimaging does not preclude meaningful recovery from locked-in syndrome: two cases of endovascularly managed basilar thrombosis

We report 2 patients with angiographically demonstrated basilar artery thrombosis who received emergent intra-arterial thrombolysis with successful recanalization of the basilar artery. In the ensuing weeks after the procedure, both patients were in a locked-in state and had sustained large bilateral regions of pontine ischemia on brain imaging. Following aggressive supportive care and rehabilitation, outcomes obtained prospectively revealed that both patients made a remarkable recovery, becoming fully independent with Barthel scores of 20 and modified Rankin scores of 2.

Treatment of extracranial carotid artery pseudoaneurysms with stent grafts: case series

BACKGROUND AND PURPOSE

Extracranial carotid artery pseudoaneurysms are a rare entity with a poorly defined natural history. Treatment has been limited to open surgical repair and limited experience with endovascular repair. We review our experience with the use of stent grafts to treat this disease entity.

METHOD

We retrospectively reviewed the interventional databases of two university hospitals (Michigan State University and University of Pittsburgh Medical Center) between 2004 and 2006 to identify patients with carotid pseudoaneurysms that were treated with stent grafts. A total of five patients were identified.

RESULTS

Of the five patients treated, four presented with acute bleeding secondary to carcinomatous invasion of the carotid artery, while one presented with thromboembolic events. Four of the five were successfully occluded with stent grafts. The one patient in whom the bleeding could not be stopped with the stent graft expired due to cardiac arrest. There were no peri-procedural complications noted as a result of stent graft placement.

CONCLUSIONS

Stent grafts can be utilized to treat pseudoaneurysms safely, but may not always stop active extravasation as an isolated therapy. Long-term data is required to determine the durability of the treatment.

Ethylenevinylalcohol copolymer (Onyx-18) used in endovascular treatment of vein of Galen malformation

BACKGROUND

Vein of Galen malformations (VGM) are rare congenital arteriovenous fistulas that usually present with heart failure in the neonate. Endovascular treatment options in the past have utilized coils, balloons, and acrylics.

CASE REPORT

We present, for the first time in the literature, a case of an infant with VGM treated initially with staged coil embolizations followed 1 year later by the transarterial and transvenous catheter based injection of Onyx-18 (ethylenevinylalcohol copolymer) in a single treatment session. The fistula was eliminated, and the infant's cardiopulmonary symptoms were improved.

Factors predicting hemorrhagic complications after multimodal reperfusion therapy for acute ischemic stroke

BACKGROUND AND PURPOSE

We sought to find predictors for hemorrhagic complications in patients with acute ischemic stroke treated with multimodal endovascular therapy.

MATERIALS AND METHODS

We retrospectively reviewed patients with acute ischemic stroke treated with multimodal endovascular therapy from May 1999 to March 2006. We reviewed clinical and angiographic data, admission CT Alberta Stroke Programme Early CT Score (ASPECTS), and the therapeutic endovascular interventions used. Posttreatment CT scans were reviewed for the presence of a parenchymal hematoma or hemorrhagic infarction based on defined criteria. Predictors for these types of hemorrhages were determined by logistic regression analysis.

RESULTS

We identified 185 patients with a mean age of 65+/-13 years and mean National Institutes of Health Stroke Scale score of 17+/-4. Sixty-nine patients (37%) developed postprocedural hemorrhages: 24 (13%) parenchymal hematomas and 45 (24%) hemorrhagic infarctions. Patients with tandem occlusions (odds ratio [OR] 4.6 [1.4-6.5], P<.016), hyperglycemia (OR 2.8 [1.1-7.7], P<.043), or treated concomitantly with intravenous (IV) tissue plasminogen activator (tPA) and intra-arterial (IA) urokinase (OR 5.1 [1.1-25.0], P<.041) were at a significant risk for a parenchymal hematoma. Hemorrhagic infarction occurred significantly more in patients presenting with an ASPECTS

CONCLUSIONS

Hemorrhagic infarctions are related to the extent of infarct based on presentation CT, whereas parenchymal hematomas are associated with the presence of tandem occlusions, hyperglycemia, and treatment with both IV tPA and IA urokinase in patients with acute stroke treated with multimodal endovascular therapy.

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Key Words Collapse

MESH Headings

• Acute Disease
• Aged
• Brain Ischemia/epidemiology
• Brain Ischemia/therapy
• Cerebral Hemorrhage/epidemiology
• Comorbidity
• Female
• Humans
• Male
• Middle Aged
• Pennsylvania/epidemiology
• Prevalence
• Reperfusion/statistics & numerical data
• Risk Assessment/methods
• Risk Factors
• Stroke/epidemiology
• Stroke/therapy
• Treatment Outcome

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Grants Collapse

Affiliation(s)

N A Vora Department of Neurology, Stroke Institute, University of Pittsburgh, Medical Center, Pittsburgh, PA 15213, USA
R Gupta
A J Thomas
M B Horowitz
A H Tayal
M D Hammer
K Uchino
L R Wechsler
T G Jovin

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Self-expanding stents for recanalization of acute cerebrovascular occlusions

BACKGROUND AND PURPOSE

Stent-assisted revascularization increases prevailing recanalization rates ( congruent with 50%-69%) for vessel occlusions recalcitrant to thrombolytics. Although balloon-mounted coronary stents can displace thrombus (via angioplasty) and retain clot along vessel walls, intracranial self-expanding stents are more flexible and exert less radial outward force during deployment, increasing deliverability and safety. To understand the effectiveness of self-expanding stents for recanalization of acute cerebrovascular occlusions, we retrospectively reviewed our preliminary experience with these stents.

MATERIALS AND METHODS

Eighteen patients (19 lesions) presenting with a clinical diagnosis of acute stroke underwent catheter-based angiography documenting focal occlusion of an intracranial artery. A self-expanding stent was delivered to the occlusion and deployed. Stent placement was the initial mechanical maneuver in 6 cases; others involved a combination of pharmacologic and/or mechanical maneuvers prestenting. GP IIb/IIIa inhibitors were administered in 10 cases intraprocedurally or immediately postprocedurally to avoid acute in-stent thrombosis.

RESULTS

Stent deployment at the target occlusion (technical success) was achieved in all cases. Thrombolysis in Cerebral Ischemia (TICI)/Thrombolysis in Myocardial Ischemia (TIMI) 2/3 recanalization (angiographic success) was achieved in 15 of 19 lesions (79%). All single-vessel lesions (n=8) were recanalized, but only 7 of 11 combination internal carotid artery and middle cerebral artery lesions were recanalized. No intraprocedural complications occurred. Seven in-hospital deaths occurred: stroke progression, 4; intracranial hemorrhage, 2; respiratory failure, 1. Seven patients had >or=4-point National Institutes of Health Stroke Scale improvement within 24 hours after the procedure, 6 had modified Rankin Score (mRS) <or=3 at discharge, and 4 had mRS <or=3 at 3 months. Overall, revascularization and improvement in clinical outcome were more likely to occur in women.

CONCLUSION

Feasibility of self-expanding stents for treatment of acute symptomatic intracranial occlusions is shown. For single-vessel lesions, stent placement with concomitant administration of IIb/IIIa inhibitors contributed to the achievement of recanalization rates exceeding those currently reported for other means of thrombolysis.

Management of symptomatic intracranial atherosclerotic disease

Recently completed prospective studies have shown that with an incidence of recurrent stroke of approximately 10% per year, significant mortality, and other vascular comorbidities, symptomatic intracranial stenosis is a marker of aggressive vascular disease. Although strict control of atherosclerotic risk factors and antithrombotic therapy preferably with antiplatelet agents should be the mainstay of treatment for every patient with this disease, some patients are likely to remain refractory to medical therapy. These high-risk patients appear to be individuals with recent symptoms and severe (> 70%) stenosis with clinical and imaging evidence of hemodynamic impairment distal to the stenotic artery. Advances in balloon and stent technology have made consideration of these high-risk patients for endovascular management with angioplasty and stenting possible, which should ideally take place as part of randomized clinical trials, because the benefit of these high-risk therapies compared with medical therapy is not yet established. This article reviews available medical treatment options for symptomatic intracranial disease and outlines the current state of endovascular therapy for this disease.

Pretreatment ipsilateral regional cortical blood flow influences vessel recanalization in intra-arterial thrombolysis for MCA occlusion

BACKGROUND AND PURPOSE

The aim of acute stroke interventions is to achieve recanalization of the target occluded artery. We sought to determine whether pretreatment cortical cerebral blood flow (CBF) was associated with vessel recanalization in patients undergoing intra-arterial therapy.

METHODS

This is a retrospective analysis of patients who underwent a quantitative xenon CT blood flow study and were noted to have a documented M1 middle cerebral artery (MCA) or carotid terminus occlusion less than 6 hours from symptom onset between January 1997 and April 2001. Twenty-three patients who underwent intra-arterial thrombolysis were included in the analysis. Univariate and multivariate analyses were performed to determine whether pretherapy CBF was correlated to the likelihood of recanalization.

RESULTS

A total of 23 patients were studied in this analysis with a median age of 69 (range 32-81) and median National Institutes of Health Stroke Score of 19 (range, 8-22). Twelve patients (52%) underwent combined intravenous/intra-arterial therapy, and 11 patients (48%) were treated with intra-arterial thrombolytics alone. Successful vessel recanalization (Thrombolysis in Myocardial Infarction classification 2 or 3 flow) occurred in 13 patients (57%). The only variable associated with recanalization in multivariate modeling was mean ipsilateral MCA CBF (odds ratio, 1.25; 95% confidence interval, 1.01-1.54; P = .035). A receiver operating characteristic curve was generated, and a mean ipsilateral MCA CBF threshold of 18 mL/100 g/min was found to be the threshold for successful recanalization.

CONCLUSIONS

Our study suggests that patients with higher mean ipsilateral MCA CBF are more likely to recanalize. The threshold for successful revascularization may be 18 mL/100 g/min. Further study is required to determine whether pretreatment CBF is related to recanalization success.

Stenting and angioplasty of the symptomatic chronically occluded carotid artery

Patients with hemodynamic impairment ipsilateral to a carotid occlusion are at a high risk of subsequent stroke, and currently 2 surgical options have been studied: extracranial-to-intracranial bypass and direct thromboendarterectomy. We report the successful revascularization of 2 symptomatic chronically occluded carotid arteries with stenting and angioplasty.

Magnesium infusion for vasospasm prophylaxis after subarachnoid hemorrhage

Object

Despite the application of current standard therapies, vasospasm continues to result in death or major disability in patients treated for ruptured aneurysms. The authors investigated the effectiveness of continous MgSO4 infusion for vasospasm prophylaxis.

Methods

Seventy-six adults (mean age 54.6 years; 71% women; 92% Caucasian) were included in this comparative matched-cohort study of patients with aneurysmal subarachnoid hemorrhage on the basis of computed tomography (CT) findings. Thirty-eight patients who received continuous MgSO4 infusion were matched for age, race, sex, treatment option, Fisher grade, and Hunt and Hess grade to 38 historical control individuals who did not receive MgSO4 infusion. Twelve grams of MgSO4 in 500 ml normal saline was given intravenously daily for 12 days if the patient presented within 48 hours of aneurysm rupture. Vasospasm was diagnosed on the basis of digital substraction angiography, CT angiography, and transcranial Doppler ultrasonography, and evidence of neurological deterioration.

Symptomatic vasospasm was present at a significantly lower frequency in patients who received MgSO4 infusion (18%) compared with patients who did not receive MgSO4 (42%) (p = 0.025). There was no significant difference in mortality rate at discharge (p = 0.328). A trend toward improved outcome as measured by the modifed Rankin Scale (p = 0.084), but not the Glasgow Outcome Scale (p = 1.0), was seen in the MgSO4-treated group.

Conclusions

Analysis of the results suggests that MgSO4 infusion may have a role in cerebral vasospasm prophylaxis if therapy is initiated within 48 hours of aneurysm rupture.

The expanded endonasal approach for an endoscopic transnasal clipping and aneurysmorrhaphy of a large vertebral artery aneurysm: technical case report

OBJECTIVE

Aneurysms of the vertebral artery are rare, comprising less than 5% of all aneurysms. They can present with subarachnoid hemorrhage, medullary compression, and cranial neuropathies. In consideration of their surrounding regional anatomy, they present a formidable surgical challenge to the neurosurgeon using traditional techniques. Recent advances in endoscopic transnasal surgery have provided an additional approach for the treatment of these difficult lesions.

CLINICAL PRESENTATION

We present a case of a large vertebral artery aneurysm causing mass effect on the medulla. Initial treatment consisted of endovascular trapping of the aneurysm; however, because of concerns that the remaining aneurysm and intraluminal thrombus was causing mass effect and continued brainstem compression, a decompressive procedure was required.

INTERVENTION

After the endovascular trapping, the patient underwent a completely endoscopic transnasal surgical clipping and aneurysmorrhaphy. After exposure of the aneurysm, distal and proximal clips were applied transnasal, and the aneurysmorrhaphy completed using suction and ultrasonic aspiration.

CONCLUSION

In consideration of their surrounding regional anatomy, aneurysms of the vertebral artery present a formidable surgical challenge to the neurosurgeon. Although endovascular techniques have proven to be extremely valuable for the treatment of these lesions, they are limited when patients have significant mass effect with brainstem compression or cranial neuropathy. Advances in endoscopic transnasal surgery have provided an additional approach for the treatment of these difficult lesions. This case report represents, to our knowledge, the first literature report of a transnasal endoscopic aneurysm clipping and thrombectomy.

Safety, feasibility, and short-term follow-up of drug-eluting stent placement in the intracranial and extracranial circulation

BACKGROUND AND PURPOSE

The use of bare metal stents to treat symptomatic intracranial stenosis may be associated with significant restenosis rates. The advent of drug-eluting stents (DESs) in the coronary circulation has resulted in a reduction of restenosis rates. We report our technical success rate and short-term restenosis rates after stenting with DESs in the intracranial and extracranial circulation.

METHODS

This study was a retrospective review of the period between April 1, 2004, and April 15, 2006, of 59 patients with 62 symptomatic intracranial or extracranial atherosclerotic lesions at 2 medical centers (University of Pittsburgh and Borgess Medical Center).

RESULTS

The mean age of our cohort was 61+/-12 years. The location of the 62 lesions was as follows: extracranial vertebral artery 31 (50%), intracranial vertebral artery or basilar artery 18 (29%), extracranial internal carotid artery (ICA) near the petrous bone 5 (8%), and intracranial ICA 8 (13%). There were 2 (3%) periprocedural complications: 1 non-flow-limiting dissection and 1 disabling stroke. Fifty vessels were available for follow-up angiography or computed tomography angiography at a median time of 4.0+/-2 months. A total of 2 of 36 extracranial stents (7%) and 1 of 26 intracranial stents (5%) were found to have restenosis > or = 50% at follow-up.

CONCLUSIONS

This report demonstrates that DES delivery in the intracranial and extracranial circulation is technically feasible. A small percentage of patients developed short-term in-stent restenosis. Longer-term follow-up is required in the setting of a prospective study to determine the late restenosis rates for DESs in comparison with bare metal stents.

What do patients with cerebral aneurysms know about their condition?

OBJECTIVE

During diagnosis and treatment, patients with cerebral aneurysms receive complex medical information. To study what patients know about their condition, we compared patients' knowledge about their aneurysm-related medical history with information in the medical record.

METHODS

Neurosurgery clinic outpatients with cerebral aneurysms were interviewed about their history of subarachnoid hemorrhage, number of aneurysms, aneurysm treatments, and treatment outcomes. Corresponding data were abstracted from the medical record by study personnel. We used kappa scores to assess the agreement between patient responses and the medical record.

RESULTS

The 178 study patients were predominantly women (71%), with a mean age of 54.4 years. The medical record showed that 56% of patients currently harbored an unsecured aneurysm, 53% had experienced a subarachnoid hemorrhage, 29% had multiple aneurysms, and 68% had undergone previous surgical or endovascular aneurysm treatment. Patient responses showed that, of the 100 patients with unsecured aneurysms, 33% were not aware that they harbored an unsecured aneurysm. Ninety percent of all patients knew whether they had experienced a subarachnoid hemorrhage (kappa = 0.81, near perfect agreement), 78% knew how many aneurysms they harbored (kappa = 0.57, moderate agreement), and 92% understood whether they had undergone previous aneurysm treatment (kappa = 0.82, near perfect agreement).

CONCLUSION

Most patients with cerebral aneurysms had an accurate understanding of many aspects of their aneurysm-related medical history. Of concern, patients were most often incorrect about the presence of an unsecured aneurysm, the issue most relevant to treatment decision-making and to their future risk of subarachnoid hemorrhage, stroke, and premature death.

Neuroform stent-assisted coil embolization of a ruptured A1 segment anterior cerebral artery aneurysm

We report a case of a 71-year-old woman who presented with a ruptured wide-necked proximal anterior cerebral artery (ACA) aneurysm that was successfully embolized using Neuroform stent-assisted coiling.

Multimodal Reperfusion Therapy for Acute Ischemic Stroke

Background and Purpose— Endovascular therapies using mechanical and pharmacological modalities for large vessel occlusions in acute stroke are rapidly evolving. Our aim was to determine whether one modality is associated with higher recanalization rates.

Methods— We retrospectively reviewed 168 consecutive patients treated with intra-arterial (IA) therapy for acute ischemic stroke between May 1999 and November 15, 2005. Demographic, clinical, radiographic, angiographic, and procedural notes were reviewed. Recanalization was defined as achieving thrombolysis in myocardial infarction 2 or 3 flow after intervention. A logistic regression model was constructed to determine independent predictors of successful recanalization.

Results— A total of 168 patients were reviewed with a mean age of 64±13 years and mean National Institutes of Health Stroke Scale score of 17±4. Recanalization was achieved in 106 (63%) patients. Independent predictors of recanalization include: the combination of IA thrombolytics and glycoprotein IIb/IIIa inhibitors (odds ratio [OR], 2.9 [95% CI, 1.04 to 6.7]; P <0.048), intracranial stent placement with angioplasty (OR, 4.8 [95% CI, 1.8 to 10.0]; P <0.001), or extracranial stent placement with angioplasty (OR, 4.2 [95% CI, 1.4 to 9.8]; P <0.014). Lesions at the terminus of the internal carotid artery were recalcitrant to revascularization (OR, 0.34 [95% CI, 0.16 to 0.73]; P value 0.006).

Conclusions— Intracranial or extracranial stenting or combination therapy with IA thrombolytics and glycoprotein IIb/IIIa inhibitors in the setting of multimodal therapy is associated with successful recanalization in patients treated with multimodal endovascular reperfusion therapy for acute ischemic stroke.

Stent-assisted intracranial recanalization for acute stroke: early results

OBJECTIVE

In patients who are not candidates for intravenous tissue plasminogen activator, intra-arterial (IA) therapy is an alternative. Current recanalization rates are 50 to 60% for IA thrombolysis. Stent-assisted recanalization in the setting of acute stroke after failed thrombolysis may improve recanalization rates.

METHODS

A retrospective analysis was performed of 19 patients treated at two institutions between July 2001 and March, 2005 with intracranial stenting of a vessel resistant to standard thrombolytic techniques. Demographics, clinical, and radiographic presentation and outcomes were studied.

RESULTS

Thirteen men and six women with a median baseline National Institutes of Health Stroke Scale (NIHSS) score of 16 (range, 15-22) were included. Eight lesions were located at the internal carotid artery terminus, seven in the M1/M2 segment, and four in the basilar artery. Average time-to-treatment was 210 +/- 160 minutes. Overall recanalization rate (Thrombolysis in Cerebral Infarction Grade 2 or 3) was 79%. There were six deaths: five due to progression of stroke and withdrawal of care at the family's request and one as the result of a delayed carotid injury after tracheostomy. One postoperative asymptomatic intracranial hemorrhage occurred without adverse affect on outcome. Median discharge NIHSS score of surviving patients was 5 (range, 2.5-11.5). Lesions at the internal carotid artery terminus (P < 0.009), older age (P < 0.003), and higher baseline NIHSS score (P < 0.009) were significant negative outcome predictors, as measured by >3 modified Rankin scale score at discharge.

CONCLUSION

Stent-assisted recanalization for acute stroke resulting from intracranial thrombotic occlusion is associated with a high recanalization rate and low intracranial hemorrhage rate. These initial results suggest that stenting may be an option for recalcitrant cerebral arterial occlusions.