Stent-Assisted Clip Placement for Complex Internal Carotid Artery Intracranial Aneurysms.

BACKGROUND: We report two procedures using a stent-assisted microsurgical clip placement to treat complex intracranial aneurysms originating from supraclinoid segment of the internal carotid artery. CASE DESCRIPTIONS: In both procedures, primary clip placement was considered technically difficult due to either complex morphology or inferior protrusion of aneurysm fundus within the interclinoid space. A nitinol self-expanding stent was placed across the neck of the aneurysm either preoperatively or intraoperatively. Obliteration of aneurysm and patency of the artery was confirmed by angiography after clip placement. CONCLUSION: Description of an integrated open microsurgical and endovascular approach and review of literature pertaining to considerations for treatment approach are discussed.

Hormone replacement therapy and the risk of subarachnoid hemorrhage in postmenopausal women.

OBJECT The incidence of subarachnoid hemorrhage (SAH) increases after menopause. Anecdotal data suggest that hormone replacement therapy (HRT) may reduce the rate of SAH and aneurysm formation in women. The goal of this study was to determine the effect of HRT on occurrence of SAH in a large prospective cohort of postmenopausal women. METHODS The data were analyzed for 93, 676 women 50-79 years of age who were enrolled in the observational arm of the Women's Health Initiative Study. The effect of HRT on risk of SAH was determined over a period of 12 ± 1 years (mean ± SD) using Cox proportional hazards analysis after adjusting for potential confounders. Additional analysis was performed to identify the risk associated with "estrogen only" and "estrogen and progesterone" HRT among women. RESULTS Of the 93, 676 participants, 114 (0.1%) developed SAH during the follow-up period. The rate of SAH was higher among women on active HRT compared with those without HRT used (0.14% vs 0.11%, absolute difference 0.03%, p < 0.0001). In unadjusted analysis, participants who reported active use of HRT were 60% more likely to suffer an SAH (RR 1.6, 95% CI 1.1-2.3). Compared with women without HRT use, the risk of SAH continued to be higher among women reporting active use of HRT (RR 1.5, 95% CI 1.0-2.2) after adjusting for age, systolic blood pressure, cigarette smoking, alcohol consumption, body mass index, race/ethnicity, diabetes, and cardiovascular disease. The risk of SAH was nonsignificantly higher among women on "estrogen only" HRT (RR 1.4, 95% CI 0.91-2.0) than "estrogen and progesterone" HRT(RR 1.2, 95% CI 0.8-2.1) after adjusting for the above-mentioned confounders. CONCLUSIONS Postmenopausal women, particularly those at risk for SAH due to presence of unruptured aneurysms, family history, or cardiovascular risk factors, should be counseled against use of HRT.

Hematoma Enlargement Among Patients with Traumatic Brain Injury: Analysis of a Prospective Multicenter Clinical Trial.

Observational studies suggest that hematomas continue to enlarge during hospitalization in patients with traumatic brain injury (TBI). There is limited data regarding factors associated with hematoma enlargement and on whether hematoma enlargement contributes directly to death and disability in patients with TBI. We analyzed data collected as part of the Resuscitation Outcomes Consortium Hypertonic Saline and TBI Study. Hematoma enlargement was ascertained and collected as a predefined safety endpoint. We evaluated the effect of hematoma enlargement on the risk of death and disability at 6 months based on the Extended Glasgow Outcome Scale (GOSE) (dichotomized as >4 or ≤4) using stepwise logistic regression analysis. We adjusted for age (continuous variable), admission GCS score (dichotomized at >5 and ≤5), and computed tomography (CT) scan classification (Marshall grades entered as a categorical variable). Of the 1200 patients with severe TBI analyzed, 238 (19.8%) patients were reported to have hematoma enlargement as an adverse event. The proportion of patients who reached favorable outcome at 6 months was significantly lower (defined by GOSE of >4) among patients with hematoma enlargement (29.0% vs. 40.1%, p<.0001). The proportion of patients who died within 6 months was significantly higher among patients with hematoma enlargement (31.9% vs. 20.7%, p<.0001). After adjusting for age, admission GCS score, and initial injury score, the odds of favorable outcome was lower in patients with hematoma enlargement (odds ratio 0.7, 95% confidence interval [CI]; 0.5-0.97). Our results suggest that hematoma enlargement may be a direct contributor to death and disability in patients with TBI at 6 months. Future clinical trials must continue to evaluate new therapeutic interventions aimed at reducing hematoma enlargement with a favorable risk benefit ratio in patients with TBI.

Detachable-Tip Microcatheters for Liquid Embolization of Brain Arteriovenous Malformations and Fistulas: A United States Single-Center Experience.

BACKGROUND: The US Food and Drug Administration recently approved a detachable-tip microcatheter, the Apollo microcatheter (eV3, Inc, Irvine, California), to prevent catheter entrapment during embolization of brain arteriovenous malformations (AVMs) using liquid embolic systems. OBJECTIVE: To report technical aspects and clinical results of cerebral embolizations with the Apollo microcatheter in 7 embolizations in 3 adult patients. METHODS: A 62-year-old man presented with an AVM in the parieto-occipital region measuring 3.6 × 1.6 cm with major cortical feeders from the right middle cerebral artery (MCA) and minor contribution from the distal right anterior cerebral artery. Two pedicles originating from the MCA were embolized. A 48-year-old woman presented with a left frontal AVM measuring 3.3 × 1.8 cm with arterial feeders from the left MCA, left middle meningeal artery, and contralateral anterior cerebral artery. Three pedicles originating from the left MCA were embolized. A 76-year-old man presented with an arteriovenous fistula with multiple fistulous connections and feeders from both vertebral and occipital arteries and the left posterior cerebral artery draining into the left transverse, torcula, and left sigmoid sinus. Two major occipital artery feeders were embolized. RESULTS: Seven Apollo microcatheters were used with the Onyx 18 liquid embolic system. The length of the detachable tip was 15 mm in 2 and 30 mm in 5 embolizations. The mean microcatheter in-position time within the pedicle was 20 minutes. Detachment of tip occurred in 3 instances. No limitations in accessing target arterial feeders and safe tip disengagement were noted despite prolonged injection times. CONCLUSION: Our initial experience supports the feasibility, safety, and effectiveness of detachable-tip microcatheters in treating brain AVMs and arteriovenous fistulas.

A population-based study of the incidence and case fatality of non-aneurysmal subarachnoid hemorrhage.

BACKGROUND: There is a paucity of reliable and recent data regarding epidemiology of non-aneurysmal subarachnoid hemorrhage (SAH) in population-based studies. OBJECTIVES: To determine the incidence and case fatality of non-aneurysmal SAH using a population-based design. METHODS: Medical records and angiographic data of all patients from Stearns and Benton Counties, Minnesota, admitted with SAH were reviewed to identify incident case of non-aneurysmal SAH. Patients with a first-time diagnosis of non-aneurysmal SAH (based on two negative cerebral angiograms performed ≥7 days apart) between June 1st, 2012 and June 30th, 2014 were considered incident cases. We calculated the incidences of non-aneurysmal and aneurysmal SAH adjusted for age and sex based on the 2010 US census. RESULTS: Of the 18 identified SAH among 189,093 resident populations, five were true incident cases of non-aneurysmal SAH in this population-based study. The age- and sex-adjusted incidence of non-aneurysmal SAH were 2.8 [95 % confidence interval (CI) 2.7-2·9] per 100,000 person-years which was lower than aneurysmal SAH incidence of 7.2 [95 % CI 7.1-7.4] per 100,000 person-years. The age-adjusted incidence of non-aneurysmal SAH was similar (compared with aneurysmal SAH) among men; 3.2 [95 % CI 3.1-3.3] per 100,000 person-years versus 2.2 [95 % CI 2.1-2.3] per 100,000 person-years, respectively. The age-adjusted case fatality rate at 3 months was 4.46 and 0.0 per 100,000 persons for aneurysmal and non-aneurysmal SAH, respectively. CONCLUSIONS: The incidence of non-aneurysmal SAH was higher than previously reported particularly among men.

Flow-independent dynamics in aneurysms: intra-aneurysm pressure measurements following complete flow cessation in internal carotid artery aneurysms.

PURPOSE: To determine if complete flow obliteration by covered stents reduces intra-aneurysm pressures in internal carotid artery (ICA) aneurysms. METHODS: A single lumen microcatheter was placed into the aneurysm sac prior to covered stent deployment in 3 patients and connected to a pressure monitoring system. The intra-aneurysm pressure was continuously monitored, and readings were recorded prior to and immediately after stent deployment and at 5-minute intervals up to 20 minutes after stent placement. Complete occlusion of flow into the aneurysms was confirmed by carotid angiography. RESULTS: There was no change in mean pressure within the aneurysm before and immediately after stent placement (80 mmHg) in any patient, nor was there a change in waveform of the intra-aneurysm pressure recording. The average of intra-aneurysm pressures among the 3 patients was higher (99 mmHg) at 10 and 15 minutes after stent placement. In 2 patients, the microcatheter was retracted into the parent arterial lumen; no difference in pressure was noted. CONCLUSION: Our observations suggest no change in the pressures within the aneurysm after complete flow cessation (flow-independent). These findings may assist clinicians in better understanding aneurysm hemodynamics and rupture after covered stent deployment.

Liquid embolization of brain arteriovenous malformation using novel detachable tip micro catheter: a technical report.

BACKGROUND AND IMPORTANCE: Liquid embolization using Onyx® of brain arteriovenous malformations (AVMs) is sometimes limited by micro catheter retention by Onyx® cast during the disengagement process. Use of the new detachable tip micro catheter is presented in this report. CLINICAL PRESENTATION: Two feeding arteries of a previously ruptured brain AVM in a 62-year-old man were embolized by Onyx 18 prior to surgery using the new Apollo™ micro catheter with the detachable-tip (30 mm) was utilized. The arterial feeders were accessed without difficulty by micro catheter, guided by 0.010" microwire. Onyx reflux around the distal end of the micro catheter was necessary for effective embolization of arteriovenous fistulous components of brain AVM. The micro catheter was successfully retracted after embolization in both feeding arteries, with distal end detachment seen in one but not the other arterial embolization. No arterial thrombosis, vasospasm, dissection, or rupture was seen at respective sites of disengagement. CONCLUSION: Use of the new micro catheters with detachable-tip design allowed prolonged Onyx® injection times, safe micro catheter disengagement, without any limitations in accessing target arterial feeders.

Acute and critical care management of a pediatric patient with medullo-cerebellar impaling.

The authors present a child with an accidental cervical medullo-cerebellar impaling by an aluminum rod. Careful planning for safe removal of the rod as well as vigilant attention to early cardiac instability and flash neurogenic pulmonary edema were paramount to her successful recovery. This patient illustrates that it is possible to survive impaling of the brainstem but it requires both innovation and collaboration by multiple specialists across different departments. The value of well coordinated and collaborative neuro surgical intensive care is demonstrated in this young girl's nearly complete recovery from the accident.

Use of therapeutic plasma exchange in the management of acute hemorrhagic leukoencephalitis: a case report and review of the literature.

BACKGROUND: Acute hemorrhagic leukoencephalitis (AHLE) is a rare, fatal, central nervous demyelinating disease characterized by a rapid fulminant clinical course. Successful management requires early diagnosis, aggressive management of cerebral edema, and immunosuppression. Therapeutic plasma exchange (TPE) is infrequently used and commences after initial management fails. CASE REPORT: A 31-year-old man presented with right arm weakness, whose symptoms rapidly progressed to hemiplegia and aphasia. The patient was initially managed with glucocorticosteroids. Decompressive craniotomy and brain biopsies were performed when his intracranial pressure increased. Brain biopsy findings were consistent with AHLE. Mycoplasma pneumonia immunoglobulin G and immunoglobulin M serologies revealed recent infection. Despite surgical and medical management, he decompensated on Day 11, and TPE was initiated. The patient received a total of 10 TPE treatments. On the fourth day of TPE treatment, he was extubated. Twenty-one days after TPE began, he was ambulating with near normal muscle strength and was discharged. Four months after initial presentation, the patient has normal strength and is working full-time. CONCLUSIONS: AHLE has a fulminant course requiring accurate and rapid diagnosis. Successful therapy requires aggressive management of intracranial pressure and immunosuppression. Two other reports of AHLE document successful management with TPE. Each of these patients survived with minimal neurologic impairments. Given the likely immune-mediated nature of this disease, combined treatment of steroids, surgery, and TPE may lead to shorter hospital stays and improved neurologic outcomes. Clinical studies are needed to further study the effect of TPE on neurologic outcome in AHLE.

Convection-enhanced delivery: targeted toxin treatment of malignant glioma.

Historically, malignant gliomas are perhaps the most difficult intracranial neoplasms to treat. Surgery, radiation therapy, and traditional chemotherapy have not been able to significantly alter the course of this disease. By definition, these tumors are located in the protected space of the cranial vault, where the blood-brain barrier prevents most therapies from gaining access. Because of the difficulty in treating this disease, new, innovative treatments and alternative delivery techniques for those therapies are needed. Targeted toxins are fusion proteins that represent a novel medical treatment for these cancers that is under development. However, the efficacy of these agents is dependent on the method of delivery to the tumor. The administration of targeted toxins requires image-guided placement of catheters, either within the tumor or into the adjacent infiltrated brain, and positive pressure infusion. The term that has been applied to this microinfusion technique is convection-enhanced delivery (CED). This infusion method was first attempted via direct intratumoral infusion in nude mouse flank tumor models of human malignant glioma. After significant development of this delivery technique in animal models, the successful demonstration of in vivo efficacy of targeted toxins in Phase I and II clinical trials was reported. Currently, ongoing targeted toxin trials are being conducted at academic health centers to define the best clinical practice for CED. This work involves refining the details of delivery such as infusion rate, duration of treatment, and drug dosing. The early results of CED of targeted toxins supports their continued investigation, as few other treatment modalities have produced durable results in the fight against gliomas.

Convection-enhanced delivery of targeted toxins for malignant glioma.

Malignant gliomas represent a difficult treatment challenge for the neuro-oncologist and the neurosurgeon. These tumours continue to be refractory to standard therapies, such as surgery, radiotherapy and conventional chemotherapy, and new therapeutic options are clearly needed. Therefore, investigators have recently taken a new direction and started to engineer compounds such as recombinant cytotoxins, antiangiogenesis factors and genetic delivery vectors. However, these promising new agents are all dependent on an effective distribution method in order to bypass the blood-brain barrier. Convection-enhanced delivery (CED) allows for the administration of targeted toxins and other agents directly into the brain at the site of a tumour via catheters placed with the aid of stereotactic or image-guided surgery. The use of this technique is gaining momentum as a newly accepted treatment modality where little else has produced durable results in the fight against gliomas. Direct intratumoural infusion was first performed in nude mouse flank tumour models of human malignant glioma. After significant testing in preclinical animal studies, this method of delivery was followed by the successful demonstration of in vivo efficacy in Phase I and II clinical trials. Currently, this technique is being used in the investigational setting at academic medical centres where investigators are starting to define the best practice for CED. Fundamental issues in this method of delivery such as rate of infusion, cannula size, infusate concentration and tissue-cannula sealing time shape the current discussion in the literature. Targeted toxin therapy represents one of the newest and most promising treatments for this unfortunate patient population, with proven clinical efficacy administered through CED, which is a novel approach to drug delivery.

Noncommunicating spinal extradural arachnoid cyst causing spinal cord compression in a child.

Extradural arachnoid cysts in the spine are relatively uncommon causes of spinal cord compression in the pediatric population that are thought to arise from congenital defects in the dura mater. Most reports describe such cysts communicating with the intrathecal subarachnoid space through a small defect in the dura. The authors describe the case of a child who presented with spinal cord compression caused by a large spinal extradural arachnoid cyst that did not communicate with the intradural subarachnoid space. An 11-year-old girl presented with urinary urgency, progressive lower-extremity weakness, myelopathy, and severe gait ataxia. Magnetic resonance imaging of the spine demonstrated a large extradural arachnoid cyst extending from T-8 to T-12. The patient underwent a thoracic laminoplasty for en bloc resection of the spinal extradural arachnoid cyst. Intraoperatively, the dura was intact and there was no evidence of communication into the intradural subarachnoid space. Postoperatively, the patient's motor strength and ambulation improved immediately, and no subsequent cerebrospinal fluid leak occurred. Noncommunicating spinal extradural arachnoid cysts are extremely rare lesions that can cause spinal cord compression in children. Because the dura remains intact, they can be removed entirely without subsequent dural repair. The authors review the literature and discuss the proposed underlying mechanisms of formation of these arachnoid cysts.