Malignant MCA territory infarction in the pediatric population: subgroup analysis of the Greater Cincinnati/Northern Kentucky Stroke Study.

PURPOSE: Malignant middle cerebral artery (MCA) infarctions are thought to be rare in children. In a recent hospital-based study, only 1.3 % of pediatric ischemic strokes were malignant MCA infarctions. However, population-based rates have not been published. We performed subgroup analysis of a population-based study to determine the rate of malignant MCA infarctions in children. METHODS: In 2005 and 2010, all ischemic stroke-related emergency visits and hospital admissions among the 1.3 million residents of the five-county Greater Cincinnati/Northern Kentucky area were ascertained. Cases that occurred in patients 18 years and younger were reviewed in detail, and corresponding clinical and neuroimaging findings were recorded. Infarctions were considered malignant if they involved 50 % or more of the MCA territory and resulted in cerebral edema and mass effect. RESULTS: In 2005, eight pediatric ischemic strokes occurred in the study population, none of which were malignant infarctions. In 2010, there were also eight ischemic strokes. Of these, two malignant MCA infarctions were identified: (1) a 7-year-old boy who underwent hemicraniectomy and survived with moderate disability at 30 days and (2) a 17-year-old girl with significant prestroke disability who was not offered hemicraniectomy and died following withdrawal of care. Thus, among 16 children over 2 years, there were two malignant MCA infarctions (12.5 %, 95 % CI 0-29). CONCLUSIONS: Malignant MCA infarctions in children may not be as rare as previously thought. Given the significant survival and functional outcome benefit conferred by hemicraniectomy in adults, future studies focusing on its potential role in pediatric patients are warranted.

Endovascular management of posthemorrhagic cerebral vasospasm: indications, technical nuances, and results.

Posthemorrhagic cerebral vasospasm (PHCV) is a common problem and a significant cause of mortality and permanent disability following aneurysmal subarachnoid hemorrhage. While medical therapy remains the mainstay of prevention against PHCV and the first-line treatment for symptomatic patients, endovascular options should not be delayed in medically refractory cases. Although both transluminal balloon angioplasty (TBA) and intra-arterial vasodilator therapy (IAVT) can be effective in relieving proximal symptomatic PHCV, only IAVT is a viable treatment option for distal vasospasm. The main advantage of TBA is its long-lasting therapeutic effect and the very low rate of retreatment. However, its use has been associated with a significant risk of serious complications, particularly vessel rupture and reperfusion hemorrhage. Conversely, IAVT is generally considered an effective and low-risk procedure, despite the transient nature of its therapeutic effects and the risk of intracranial hypertension associated with its use. Moreover, newer vasodilator agents appear to have a longer duration of action and a much better safety profile than papaverine, which is rarely used in current clinical practice. Although endovascular treatment of PHCV has been reported to be effective in clinical series, whether it ultimately improves patient outcomes has yet to be demonstrated in a randomized controlled trial.

Pediatric brain tumors in Puerto Rico.

OBJECTIVE: To determine the frequency of pediatric brain tumors treated at the University Pediatric Hospital of Puerto Rico over a 6-year period and examine the demographic data and tumor histology of patients in different age groups. METHODS: A retrospective study was undertaken at the University Pediatric Hospital. We included patients with brain tumors that had been newly diagnosed during the period covering from January 2002 to December 2007. All cases were analyzed by age, gender, histologic diagnosis, and affected area. RESULTS: One hundred thirty-six patients were included in the study. Overall, males were more frequently affected than were females. Children in the 1 to 4 years old age group had the highest number of newly diagnosed brain tumors. Regarding anatomic location, supratentorial tumors were more frequent than were infratentorial tumors. The most common single tumor was the pilocytic astrocytoma (WHO grade I), representing 31% of the total pediatric brain tumors. CONCLUSION: Our results provide an objective platform for further epidemiological studies and for the development of local health strategies for the timely diagnosis and treatment of the most common pediatric tumors in Puerto Rico.

Pilomyxoid astrocytoma in unusual location in a child with neurofibromatosis type 1: case report and review of the literature.

Pilomyxoid astrocytoma (PMA) is a recently defined brain tumor believed to be a variant of pilocytic astrocytoma (PA), but with a more aggressive course. Most PMAs occur in the optic-chiasmatic/hypothalamic (OCH) region but they have also been described in the posterior fossa, temporal lobe, and in the spinal cord. We report a girl with history of neurofibromatosis type 1 (NF-1) who presented with a PMA located in the left lateral ventricle. Despite the fact that most of PMAs occur in the hypothalamic region, high awareness should be given to lesions in unusual locations, thus expanding the current epidemiologically known locations for this tumor.

Endoscopic third ventriculostomy: a surgeon's experience.

INTRODUCTION: Endoscopic third ventriculostomy (ETV) is considered an alternative treatment for certain types ofhydrocephalus. Depending on patient's age and etiology of hydrocephalus, it carries a success rate of around 90%. However, as in any surgical procedure, inherent risks are present and a risk-benefit analysis must be done prior to selecting patients for this intervention. OBJECTIVE: To evaluate retrospectively the experience of ETV at the University of Puerto Rico and examine the etiological factors, demographic data and symptoms among the Puerto Rico population. This study represents the data of one neurosurgeon and is the first account of endoscopic third ventriculostomy as a mode of treatment in the Caribbean area. METHODS: Retrospective analysis was undertaken of 29 patients treated at the University Pediatric Hospital (UPH) and University District Hospital (UDH) in San Juan was undertaken Different etiologies of hydrocephalus were identified and managed. RESULTS: The most common indication for ETV was aqueductal stenosis (59%) with male predominance (55%). Also, the most common population treated were adults (72%) and the most common symptom presented were headaches (52%) and gait disturbances (43%). CONCLUSIONS: Endoscopic third ventriculostomy is a safe and effective way to treat hydrocephalus and should be considered as first choice of treatment for certain patients with hydrocephalus unless otherwise contraindicated.

Descriptive profile of surgically-confirmed adult central nervous system tumors in Puerto Rico.

INTRODUCTION: Published studies regarding the incidence of central nervous system (CNS) tumors in Puerto Rico (PR) are exceedingly rare. The general understanding is that the incidence of these tumors in Puerto Rico is similar to the one found in the United States of America (USA). The objective of this study is to describe the specific profile of all the CNS tumors that are surgically intervened in Puerto Rico, through the creation of a database. METHODS: A retrospective analysis of all the surgical procedures from January 1, 2002 to May 31, 2006 for adult CNS tumors in Puerto Rico was performed. Each case was evaluated for demographic information, operative procedure, lesion description and official pathological report. Recurrent lesions were excluded. The information was organized to form a database of all the CNS neoplasms. RESULTS: A total of 1,018 procedures for CNS tumors were performed on 1,005 patients. The incidence rate of surgically intervened CNS tumors in Puerto Rico is 6 per 100,000 people. CNS tumors were more common in women than in men (58% vs. 42%), respectively. The mean age was 52.4 years. The most common histological type found was meningioma WHO I (24%), followed by pituitary adenomas (16%), and glioblastoma multiforme (14%). CONCLUSIONS: Our results reflect a unique histopathological distribution of operated CNS tumors in Puerto Rico. In this series, primary tumors are more common than metastatic tumors. Benign histological tumors were more frequent than more malignant variants. Although this study reflects only the histologically diagnosed tumors, it is headway towards diagnosing the incidence of all CNS tumors in Puerto Rico.

Prolactinoma with extensive amyloid deposits: a case report.

Prolactinomas are common benign pituitary neoplasms. Amyloid deposits are rare findings that have been reported in pituitary neoplasms. We report a case of a 48-year old man with a diagnosis of prolactinoma with extensive amyloid deposition. To our knowledge, this is the first case of amyloid in a pituitary neoplasm at our institution.

The Interlenticulostriate Approach to Very High-Riding Distal Basilar Trunk Aneurysms.

BACKGROUND: Most high-riding distal basilar trunk aneurysms can be surgically approached via the transsylvian route and its orbitozygomatic variant. However, on rare occasions, the basilar bifurcation may be unusually high and an approach above the carotid terminus may be required. OBJECTIVE: In this cadaveric study, we sought to determine the feasibility and exposure limits of the interlenticulostriate approach (ILSA). METHODS: A standard transsylvian approach was performed in 10 cerebral hemispheres of 5 formalin-fixed, silicone-injected cadaver heads. The interpeduncular cistern was exposed via the opticocarotid window, carotid-oculomotor window, and supracarotid ILSA window. The latter was measured and an aneurysm clip or ventriculostomy stylet was placed as high as possible through each corridor. Using noncontrast 3-D rotational angiography, clip/stylet positions were measured relative to the dorsum sellae. RESULTS: ILSA provided a 9.4 × 4.6 mm mean surgical corridor, just enough room for a standard clip applier. This space was limited by the carotid bifurcation inferiorly, the lenticulostriate arteries medially and laterally, and the optic tract superiorly. There was no difference between opticocarotid and carotid-oculomotor windows, in terms of clip position (+8.9 vs +8.6 mm, respectively; P = .78). In contrast, ILSA provided significantly improved superior exposure, compared with either approaches (mean stylet position: +14.3 mm; P = .005). The exposure benefit afforded by ILSA was consistent across all 10 hemispheres, ranging from +2.5 to +8 mm. CONCLUSION: For high-riding distal basilar trunk aneurysms that cannot be reached via the frontotemporal orbitozygomatic approach, ILSA can provide a viable route of access. Vascular neurosurgeons should be familiarized with this approach.

The role of endovascular therapy in the treatment of acute ischemic stroke.

Of the approximately 795,000 strokes in the United States annually, 87% are ischemic and result in significant morbidity and mortality. Improvements in acute ischemic stroke (AIS) outcomes have been achieved with intravenous thrombolytics (IVT) and intra-arterial thrombolytics vs supportive medical therapy. Given its ease of administration, noninvasiveness, and most validated efficacy, IVT is the standard of care in AIS patients without contraindications to systemic fibrinolysis. However, patients with large-vessel occlusions respond poorly to IVT. Recent trials designed to select this population for randomization to IVT vs IVT with adjunctive endovascular therapy have not shown improvement in clinical outcomes with endovascular therapy. This could be due to the lack of utilization of modern thrombectomy devices such as Penumbra aspiration devices, Solitaire stent-trievers, or Trevo stent-trievers, which have shown the best recanalization results. Continued improvement in the techniques with using these devices as well as randomized controlled trials using them is warranted. This article defines the goals of AIS revascularization, presents the evolution of treatment from the initial use of IVT to modern thrombectomy devices, and discusses current treatment and ongoing AIS trials.

Management of vasospasm in ruptured unsecured intracranial vascular lesions: review of 10 cases.

INTRODUCTION: Risks associated with endovascular management remain unaddressed for post-hemorrhagic cerebral vasospasm (PHCV) caused by pathologies that cannot be secured or identified before vasospasm treatment. This retrospective study reviews our 10 year experience in the difficult scenario of subarachnoid hemorrhage (SAH) with vasospasm, including intra-arterial vasodilators or percutaneous transluminal angioplasty (PTA) to vessels feeding a ruptured unsecured lesion. METHODS: 10 SAH patients with ruptured unsecured vascular lesions underwent 44 endovascular treatments for PHCV (2002-2011). We defined unsecured as an untreated aneurysm/dissection, incompletely coiled aneurysm, dissection covered with self-expanding nitinol stents, or angiographically negative SAH. Treatments were categorized by location of the ruptured unsecured (partial or complete) lesion relative to the vessel treated for vasospasm. RESULTS: Our 10 patients with four aneurysms, four dissections, and two angiographically negative SAH accounted for 10.3% of SAH patients who underwent angiography for vasospasm. No procedure related complications occurred when treating vessels not supplying the index lesion or with angiographically negative SAH. Of the endovascular treated vessels supplying partially secured lesions, one (6.3%) fatal complication occurred; none of these patients receiving only vasodilators had complications. With endovascular treatment of PHCV with completely unsecured lesions, one (33%) complication was fatal. CONCLUSIONS: Endovascular treatment appeared safe for PHCV for vessels not supplying the index arterial lesion and for angiographically negative SAH. Vasodilators were safe for vessels harboring partially secured, ruptured lesions (eg, incompletely coiled aneurysms, stented dissections). Following two major complications, the safety of administering vasodilators or performing PTA to vessels supplying completely unsecured vascular lesions remains inconclusive and should be used cautiously.

Predicting parent vessel patency and treatment durability: a proposed grading scheme for the immediate angiographic results following Onyx HD-500 embolization of intracranial aneurysms.

INTRODUCTION: Onyx HD-500 embolization of intracranial aneurysms leads to high rates of complete and durable occlusion. However, little information exists as to what constitutes an optimal immediate angiographic result. We devised a simple grading scheme based on the pattern of parent artery and aneurysm neck reconstruction, and correlated it with long term outcome. METHODS: All cases of Onyx embolization for unruptured aneurysms performed between September 2008 and April 2010 were retrospectively reviewed. Immediate angiographic results were categorized according to the pattern of extra-aneurysmal Onyx leakage: grade A, none; grade B, 'hat brim' lamination; and grade C, 'ectopic' Onyx (C1, non-flow limiting; C2, flow limiting). Results of follow-up vascular imaging were reviewed and correlated with the angiographic grade. RESULTS: 24 embolization procedures were performed in 21 patients with 23 aneurysms. Aneurysm size ranged from 2.5 to 24 mm and neck width from 2 to 8 mm. Complete occlusion was achieved in 20 cases (83.3%) and subtotal occlusion in three (12.5%). Immediate angiographic results were: grade A in ten (41.7%), grade B in eight (33.3%), and grade C in six (25%). Stable angiographic results were seen in 85%, 94%, 94%, and 100% at 6, 12, 24, and 36 months, respectively. Angiographic recurrence was observed in four cases (16.7%), all grade A (p=0.006). Delayed parent vessel occlusion occurred in two cases (8.3%), both grade C2 (p=0.014). CONCLUSIONS: This simple grading system may help predict long term angiographic results. Hat brim Onyx lamination seems to provide an optimal balance between treatment durability and parent vessel patency. Prospective validation is warranted.

Onyx HD-500 embolization of intracranial aneurysms: modified technique using continuous balloon inflation under conscious sedation.

The conventional technique of intracranial aneurysm embolization using Onyx HD-500 (ev3 Neurovascular, Irvine, CA, USA) involves repetitive balloon inflation-deflation cycles under general anesthesia. By limiting parent artery occlusion to 5 minutes, this cyclic technique is thought to minimize cerebral ischemia. However, intermittent balloon deflation may lengthen procedure time and allow balloon migration, resulting in intimal injury or Onyx leakage. We report our experience using a modified technique of uninterrupted Onyx injection with continuous balloon occlusion under conscious sedation. All Onyx embolization procedures for unruptured aneurysms performed by the senior author (A.J.R.) between September 2008 and April 2010 were retrospectively reviewed. Demographic, clinical, angiographic, and procedural data were recorded. Twenty-four embolization procedures were performed in 21 patients with 23 aneurysms, including four recurrences. Twenty aneurysms (87%) involved the paraclinoid or proximal supraclinoid internal carotid artery. Size ranged from 2.5 to 24mm and neck diameter from 2 to 8mm. The modified technique was employed in 19 cases. All but one patient (94.4%) tolerated continuous balloon inflation. Complete occlusion was achieved in 20 aneurysms (83.3%) and subtotal occlusion in three (12.5%). Stable angiographic results were seen in 85%, 94%, 94%, and 100% of patients at 6, 12, 24, and 36months, respectively. There were no deaths. Permanent non-disabling neurological morbidity occurred in one patient (4.2%). Minor, transient, and/or angiographic complications were seen in three patients (12.5%), none related to the technique itself. Onyx embolization of unruptured intracranial aneurysms can be safely and effectively performed using continuous balloon inflation under conscious sedation.

Early reperfusion and clinical outcomes in patients with M2 occlusion: pooled analysis of the PROACT II, IMS, and IMS II studies.

OBJECT: The role of endovascular therapy in patients with acute ischemic stroke and a solitary M2 occlusion remains unclear. Through a pooled analysis of 3 interventional stroke trials, the authors sought to analyze the impact of successful early reperfusion of M2 occlusions on patient outcome. METHODS: Patients with a solitary M2 occlusion were identified from the Prolyse in Acute Cerebral Thromboembolism (PROACT) II, Interventional Management of Stroke (IMS), and IMS II trial databases and were divided into 2 groups: successful reperfusion (thrombolysis in cerebral infarction [TICI] 2-3) at 2 hours and failed reperfusion (TICI 0-1) at 2 hours. Baseline characteristics and clinical outcomes were compared. RESULTS: Sixty-three patients, 40 from PROACT II and 23 from IMS and IMS II, were identified. Successful early angiographic reperfusion (TICI 2-3) was observed in 31 patients (49.2%). No statistically significant difference in the rates of intracerebral hemorrhage (60.9% vs 47.6%, p = 0.55) or mortality (19.4% vs 15.6%, p = 0.75) was observed. However, there was a trend toward higher incidence of symptomatic hemorrhage in the TICI 2-3 group (17.4% vs 0%, p = 0.11). There was also a trend toward higher baseline glucose levels in this group (151.5 mg/dl vs 129.6 mg/ dl, p = 0.09). Despite these differences, the rate of functional independence (modified Rankin Scale Score 0-2) at 3 months was similar (TICI 2-3, 58.1% vs TICI 0-1, 53.1%; p = 0.80). CONCLUSIONS: A positive correlation between successful early reperfusion and clinical outcome could not be demonstrated for patients with M2 occlusion. Irrespective of reperfusion status, such patients have better outcomes than those with more proximal occlusions, with more than 50% achieving functional independence at 3 months.

Changes in computed tomography perfusion parameters after superficial temporal artery to middle cerebral artery bypass: an analysis of 29 cases.

Introduction Analysis of computed tomography perfusion (CTP) studies before and after superficial temporal artery to middle cerebral artery (STA-MCA) bypass is warranted to better understand cerebral steno-occlusive pathology. Methods Retrospective review was performed of STA-MCA bypass patients with steno-occlusive disease with CTP before and after surgery. CTP parameters were evaluated for change after STA-MCA bypass. Results A total of 29 hemispheres were bypassed in 23 patients. After STA-MCA bypass, mean transit time (MTT) and time to peak (TTP) improved. When analyzed as a ratio to the contralateral hemisphere, MTT, TTP, and cerebral blood flow (CBF) improved. There was no effect of gender, double vessel versus single vessel bypass, or time until postoperative CTP study to changes in CTP parameters after bypass. Conclusions Blood flow augmentation after STA-MCA bypass may best be assessed by CTP using baseline MTT or TTP and ratios of MTT, TTP, or CBF to the contralateral hemisphere. The failure of cerebrovascular reserve to improve after cerebral bypass may indicate irreversible loss of autoregulation with chronic cerebral vasodilation or the inability of CTP to detect these improvements.

Inhibition of Protein kinase Mzeta (PKMζ) in the mesolimbic system alters cocaine sensitization in rats.

Chronic cocaine use produces long-lasting changes in reward circuits that may underlie the transition from casual to compulsive patterns of drug use. Although strong neuroadaptations within the mesocorticolimbic system are known to occur, the specific role of these drug-induced plasticities on sensitization remains to be elucidated. Here we investigate whether PKMζ, a protein involved in maintaining long-term potentiation (LTP), plays a role in these cocaine-induced changes in synaptic strengthening. We performed whole-cell voltage clamp recordings of putative ventral tegmental area (VTA) dopamine (DA) cells 24 hours after five days of 15 mg/kg i.p. cocaine or isovolumetric saline injections. We observed that superfusion of 5µM ZIP (PKMζ inhibitory peptide) decreased AMPA currents and AMPA/NMDA ratios only in cocaine sensitized rats. In vivo ZIP microinfusions (10 nmol) into the VTA after cocaine sensitization decreased locomotor activity on a subsequent cocaine challenge only if given ZIP is given before the withdrawal period. On the other hand, ZIP microinfusions into the nucleus accumbens (NAc) core after a seven days withdrawal period disrupt the expression of locomotor sensitization. The present data provide a potentially relevant region, and time-specific PKMζ-dependent brain mechanism that enables sensitization. Our results support the vision that addiction involves a pathological learning process. They imply that if this synaptic strengthening is reversed, changes in the behavioral response may also be overturned.

Systemic exposure to paraquat and maneb models early Parkinson's disease in young adult rats.

In recent years, several lines of evidence have shown an increase in Parkinson's disease (PD) prevalence in rural environments where pesticides are widely used. Paraquat (PQ--herbicide) and maneb (MB--fungicide) are among the compounds suspected to induce neuronal degeneration and motor deficits characteristics of PD. Here, we investigated the effects of PQ and MB on dopaminergic (DA) neuron-glia cultures and in vivo in young adult rats. In vitro, PQ led to a loss of DA as compared to non-DA neurons and microglial activation in a dose-dependent manner. Addition of MB had no further effect nor did it lead to microglial activation when used alone. In vivo, 2-month old young adult rats were subjected to intraperitoneal injections of vehicle (n = 4), PQ alone (n = 8), or PQ in combination with MB (n = 8) twice a week for 4 weeks and were sacrificed the day following the last injection. Significant loss of nigral DA neurons was observed in both treatment groups, but a significant decrease in striatal DA fibers was not found. Microglial activation was seen in the nigra of rats subjected to PQ with or without MB. Behavioral analyses demonstrated a mixed pattern of motor impairments, which may have been related to early effects of nigral DA neuronal loss or systemic effects associated with MB exposure in addition to PQ. These results indicate that exposure to PQ with or without MB induces neurodegeneration which might occur via an early inflammatory response in young adult animals.