Cerebral revascularization model in a swine

The purpose of this study was to analyze the suitability of the cerebral vasculature of the pig regarding a revascularization procedure. In two 60 kg pigs the femoral artery was exposed and canulated for selective angiography and interventional procedures. After the angiography, the pigs were brought to the animal OR for craniotomy and analysis of the intracranial cerebral arteries and the surgical exposure of the carotid arteries under the microscope. Angiography demonstrated the presence of a true internal-, external carotid artery and vertebral arteries. Both the vertebral and internal carotid arteries are feeding a rete mirabilis both at the cranial base and the cranio-cervical junction. At these sites further advancement of the angiography catheter was not possible. Out of these rete mirabilis, an intracranial carotid artery and an intracranial vertebral artery were formed, respectively. The intracranial cerebral vessels were of the dimension of 1 mm and less. The extracranial portion of the internal carotid artery was 2.5 mm of diameter. From these findings, we conclude that a direct cerebral revascularization procedure of the intracranial vessels is not possible in the swine. However, a global revascularization procedure on the extracranial portion of the internal carotid artery is thus feasible, both using a low- and high-flow anastamosis technique.

rCBF in hemorrhagic, non-hemorrhagic and mixed contusions after severe head injury and its effect on perilesional cerebral blood flow

Intracerebral contusions can lead to regional ischemia caused by extensive release of excitotoxic aminoacids leading to increased cytotoxic brain edema and raised intracranial pressure. rCBF measurements might provide further information about the risk of ischemia within and around contusions. Therefore, the aim of the presented study was to compare the intra- and perilesional rCBF of hemorrhagic, non-hemorrhagic and mixed intracerebral contusions. In 44 patients, 60 stable Xenon-enhanced CT CBF-studies were performed (EtCO2 30 +/- 4 mmHg SD), initially 29 hours (39 studies) and subsequent 95 hours after injury (21 studies). All lesions were classified according to localization and lesion type using CT/MRI scans. The rCBF was calculated within and 1-cm adjacent to each lesion in CT-isodens brain. The rCBF within all contusions (n = 100) of 29 +/- 11 ml/100 g/min was significantly lower (p < 0.0001, Mann-Whitney U) compared to perilesional rCBF of 44 +/- 12 ml/100 g/min and intra/perilesional correlation was 0.4 (p < 0.0005). Hemorrhagic contusions showed an intra/perilesional rCBF of 31 +/- 11/44 +/- 13 ml/100 g/min (p < 0.005), non-hemorrhagic contusions 35 +/- 13/46 +/- 10 ml/100 g/min (p < 0.01). rCBF in mixed contusions (25 +/- 9/44 +/- 12 ml/100 g/min, p < 0.0001) was significantly lower compared to hemorrhagic and non-hemorrhagic contusions (p < 0.02). Intracontusional rCBF is significantly reduced to 29 +/- 11 ml/100 g/min but reduced below ischemic levels of 18 ml/100 g/min in only 16% of all contusions. Perilesional CBF in CT normal appearing brain closed to contusions is not critically reduced. Further differentiation of contusions demonstrates significantly lower rCBF in mixed contusions (defined by both hyper- and hypodense areas in the CT-scan) compared to hemorrhagic and non-hemorrhagic contusions. Mixed contusions may evolve from hemorrhagic contusions with secondary increased perilesional cytotoxic brain edema leading to reduced cerebral blood flow and altered brain metabolism. Therefore, the treatment of ICP might be individually modified by the measurement of intra- and pericontusional cerebral blood.

A rare anomaly of the anterior communicating artery complex hidden by a large broad-neck aneurysm and disclosed by three-dimensional rotational angiography

Double fenestration of the anterior communicating artery (ACoA) complex associated with an aneurysm is a very rare finding and is usually caused by ACoA duplication and the presence of a median artery of the corpus callosum (MACC). We present a patient in whom double fenestration was not associated with ACoA duplication or even with MACC, representing therefore, a previously unreported anatomic variation. A 43 year old woman experienced sudden headache and the CT scans showed subarachnoid haemorrhage (SAH). On admission, her clinical condition was consistent with Hunt and Hess grade II. Conventional digital subtraction angiography (DSA) was performed and revealed multiple intracranial aneurysms arising from both middle cerebral arteries (MCA) and from the ACoA. Three-dimensional rotational angiography (3D-RA) disclosed a double fenestration of the ACoA complex which was missed by DSA. The patient underwent a classic pterional approach in order to achieve occlusion of both left MCA and ACoA aneurysms by surgical clipping. The post-operative period was uneventful. A rare anatomical variation characterised by a double fenestration not associated with ACoA duplication or MACC is described. The DSA images missed the double fenestration which was disclosed by 3D-RA, indicating the importance of 3D-RA in the diagnosis and surgical planning of intracranial aneurysms.

Pineal parenchymal tumor of intermediate differentiation: diagnostic pitfalls and discussion of treatment options of a rare tumor entity

Tumors of the pineal region are uncommon, comprising approximately 0.4-1% of all intracranial tumors in adults in European and American series. Histopathologically, they are a very heterogeneous group of tumors. Of genuine pineal tumors, pineal parenchymal tumors of intermediate differentiation (PPTIDs) are the least frequently found type. In this paper, we report on the case of a patient with an unexpected and difficult-to-diagnose PPTID. A 2.2 x 2.2-cm midline mass within the posterior part of the third ventricle with consecutive obstructive hydrocephalus was found in a 44-year-old man presenting with diplopia and gait disturbances. There was no clear connection of the tumor to the pineal gland. Differential diagnosis included all intraventricular and midline tumors, therefore a biopsy was taken. Preliminary histopathological diagnosis was germinoma or primitive neuroectodermal tumor, and the tissue sample was reexamined by a referential neuropathological institute. Final diagnosis was PPTID. The tumor was then resected through a transventricular/transchoroidal approach. Histopathological examination of tumor specimen confirmed the diagnosis of a PPTID. Postoperatively, the patient received gamma-knife radiosurgery. At 1-year follow-up, there are no signs of tumor regrowth. Diagnosis of pineal parenchymal tumors in general and PPTIDs in particular can be troublesome. Their histopathological features are still being defined, as is the biological behavior of the different tumor entities. Thus, treatment options including surgery, radiation therapy, and chemotherapy remain controversial. We recommend surgical removal of PPTID, preferably in toto whenever the size of the tumor permits that kind of excision.

Simultaneous, bilateral anterior ischemic optic neuropathy (AION) in polycythemia vera: a case report

BACKGROUND: Polycythemia vera (PV) is a hemopoetic disorder. Apparently, although thrombosis accounts for the majority of morbidity, AION has not been associated with PV so far. PATIENT AND FINDINGS: A 63 y-old woman with PV was hospitalized because of acute liver failure. She also experienced bilateral painless loss of vision. Bilateral, pale optic disc swelling with flame-like hemorrhages, more pronounced in the right eye, constricted visual fields, and relative afferent papillary defect (RAPD) on the right side were present. Computer tomography scan revealed no signs of intraorbital pathology, elevated intracranial pressure or hemorrhages. CLINICAL COURSE: We interpreted the findings as AION associated with the hyperviscosity syndrome. Liver transplantation had to be carried out in the next days. Three weeks later, vision improved slightly, but RAPD persisted, and disc pallor developed in both eyes. The patient died two months later. DISCUSSION: Central retinal artery and vein occlusions have been described as complications of Essential thrombocythemia, but not of PV. We observed a rare case of bilateral neuropathy suggestive of AION. This condition has so far not been associated with PV.

Postpartum cervicocephalic artery dissection

BACKGROUND AND PURPOSE: Cervicocephalic artery dissection (CAD) after childbirth is rare. The objective of this study was to determine differences between postpartum and nonpostpartum CAD. METHODS: We compared consecutive patients with postpartum CAD with a control group of women with nonpostpartum CAD. RESULTS: Of 245 patients with CAD, 102 women <50 years (6 with postpartum CAD and 96 with nonpostpartum CAD) were identified. Vascular risk factors and presenting characteristics did not differ significantly between postpartum CAD and nonpostpartum CAD women. By contrast, patients with postpartum CAD had more often coexisting conditions such as reversible cerebral vasoconstriction syndrome (2 of 6 versus 2 of 96; P=0.017), reversible posterior leukoencephalopathy syndrome (2 of 6 versus one of 96; P=0.009), and subarachnoid hemorrhage without signs of intracranial extension of CAD (2 of 6 versus zero of 96; P=0.003). CONCLUSIONS: CAD and associated conditions should be looked for in women with unusual headache after childbirth.

[The comatose child]

The child who presents with acute coma runs a high risk of cardiopulmonary insufficiency, direct brain injury or even cerebral herniation. The case-management of such child requires a coma-specific emergent evaluation, immediate treatment of any hypoxicischemic insults and of the underlying cause. The coma-specific examination includes performance of child-adapted Glasgow Coma Score, the evaluation of brain stem functions such as pupillary response to light, cough- and gag reflex, and determination of all vital signs including body temperature. Treatment of hypoxicischemic insults includes control of airways and ventilation in patient with coma defined as GCS <8; liberal treatment of impaired cardiovascular states with isotonic fluids such as 0.9% sodium chloride; and treatment of cerebral herniation with head elevation, mannitol, hypertonic sodium chlorid fluids, steroids and hyperventilation. Immediately treatable causes are hypoglycemia, meningitis/encephalitis, opioid overdose and status epilepticus. Exclusion of rapidly progressive intracranial lesions almost always requires referral to the tertiary centre with head CT-scan facilities. Finally, an extensive etiology search of the stable coma is performed by looking for disease or trauma of the brain, for metabolic causes, for intoxications and for cardiopulmonary problems.

Depiction of small veins draining into the vein of galen using preoperative 3-dimensional navigation in living patients

OBJECTIVE: The purpose of this study was to delineate the anatomy of the precentral cerebellar vein, superior vermian vein, and internal occipital vein using reconstructions of computed tomographic and magnetic resonance imaging scans with navigation software. These data were compared with previous anatomic and angiographic findings to show the resolution and accuracy of the system. METHODS: We retrospectively reviewed 100 patients with intracranial pathologies (50 computed tomographic scans with contrast and 50 magnetic resonance imaging scans with gadolinium) using a neuronavigation workstation for 3-dimensional reconstruction. Particular attention was paid to depiction of the precentral cerebellar vein, superior vermian vein, and internal occipital vein. The data were reviewed and analyzed. RESULTS: The precentral cerebellar vein, superior vermian vein, and its tributary, the supraculminate vein, were depicted in 52 (52%) patients. The internal occipital vein was delineated on 99 (49.5%) sides and joined the basal vein and vein of Galen in 39 (39.4%) and 60 (60.6%) hemispheres, respectively. Comparing these results with previous angiographic studies, the ability of the neuronavigation system for depicting these vessels is similar to that of digital subtraction angiography. CONCLUSION: This study illustrates the possibility of depicting the small vessels draining into the pineal region venous complex using 3-dimensional neuronavigation with an accuracy comparable to that of digital subtraction angiography. This tool provides important information for both surgical planning and intraoperative orientation.

Decompressive craniectomy in subarachnoid hemorrhage

OBJECT: The aim of this study was to analyze decompressive craniectomy (DC) in the setting of subarachnoid hemorrhage (SAH) with bleeding, infarction, or brain swelling as the underlying pathology in a large cohort of consecutive patients. METHODS: Decompressive craniectomy was performed in 79 of 939 patients with SAH. Patients were stratified according to the indication for DC: 1) primary brain swelling without or 2) with additional intracerebral hematoma, 3) secondary brain swelling without rebleeding or infarcts, and 4) secondary brain swelling with infarcts or 5) with rebleeding. Outcome was assessed according to the modified Rankin Scale (mRS) at 6 months (mRS Score 0-3 favorable vs 4-6 unfavorable). RESULTS: Overall, 61 (77.2%) of 79 patients who did and 292 (34%) of the 860 patients who did not undergo DC had a poor clinical grade on admission (World Federation of Neurosurgical Societies Grade IV-V, p < 0.0001). A favorable outcome was attained in 21 (26.6%) of 79 patients who had undergone DC. In a comparison of favorable outcomes in patients with primary (28.0%) or secondary DC (25.5%), no difference could be found (p = 0.8). Subgroup analysis with respect to the underlying indication for DC (brain swelling vs bleeding vs infarction) revealed no difference in the rate of favorable outcomes. On multivariate analysis, acute hydrocephalus (p = 0.009) and clinical signs of herniation (p = 0.02) were significantly associated with an unfavorable outcome. CONCLUSIONS: Based on the data in this study the authors concluded that primary as well as secondary craniectomy might be warranted, regardless of the underlying etiology (hemorrhage, infarction, or brain swelling) and admission clinical grade of the patient. The time from the onset of intractable intracranial pressure to DC seems to be crucial for a favorable outcome, even when a DC is performed late in the disease course after SAH.

Clinical experience with the use of bivalirudin in a large population undergoing endovascular abdominal aortic aneurysm repair

PURPOSE: To retrospectively evaluate the safety and effectiveness of the use of bivalirudin, a direct thrombin antagonist, compared with unfractionated heparin in endovascular aneurysm repair (EVAR). MATERIALS AND METHODS: Between March 1994 and September 2007, 740 consecutive patients (mean age, 75.7 y +/- 7.7; 69 women) underwent elective EVAR for infrarenal abdominal aortic aneurysm. Bivalirudin was used in 98 of these 740 (13.2%) and unfractioned heparin was used in the other 642 (86.8%). Complications were classified according to the Society of Vascular Surgery/International Society for Cardiovascular Surgery criteria. Major bleeding was defined as clinically overt blood loss resulting in a decrease of hemoglobin of more than 3 g/dL, any decrease in hemoglobin of more than 4 g/dL, transfusion of 2 U or more of red blood cells, or intracranial or retroperitoneal hemorrhage. RESULTS: Grade 1 major complications were observed in 161 of 642 patients (25.2%) in the heparin group and 12 of 98 patients (12.2%) in the bivalirudin group (P = .0046), whereas the incidences of grade 3 major complications were not significantly different between groups (P = .57). The rate of total complications was higher in the heparin group than in the bivalirudin group (247 of 642 [38.5%] vs 21 of 98 [21.4%]; P = .001). Major bleeding occurred in 10 of 98 patients (10.2%) receiving bivalirudin and in 91 of 642 patients (14.2%) receiving heparin (P = .34). One of 21 major complications (4.76%) in the bivalirudin group and 12 of 247 major complications (4.86%) in the heparin group were attributable to thrombosis (P = 1.0). CONCLUSIONS: Bivalirudin is a safe and feasible alternative to unfractionated heparin in patients undergoing EVAR.

Intravenous thrombolysis in stroke attributable to cervical artery dissection

BACKGROUND AND PURPOSE: Intravenous thrombolysis (IVT) for stroke seems to be beneficial independent of the underlying etiology. Whether this is also true for cervical artery dissection (CAD) is addressed in this study. METHODS: We used the Swiss IVT databank to compare outcome and complications of IVT-treated patients with CAD with IVT-treated patients with other etiologies (non-CAD patients). Main outcome and complication measures were favorable 3-month outcome, intracranial cerebral hemorrhage, and recurrent ischemic stroke. Modified Rankin Scale score Intracranial cerebral hemorrhages (asymptomatic, symptomatic, fatal) were equally frequent in CAD (14% [7%, 7%, 2%]) and non-CAD patients (14% [9%, 5%, 2%]; P=0.99). Recurrent ischemic stroke occurred in 1.8% of patients with CAD and in 3.7% of non-CAD-patients (P=0.71). CONCLUSIONS: IVT-treated patients with CAD do not recover as well as IVT-treated non-CAD patients. However, intracranial bleedings and recurrent ischemic strokes were equally frequent in both groups. They do not account for different outcomes and indicate that IVT should not be excluded in patients who may have CAD. Hemodynamic compromise or frequent tandem occlusions might explain the less favorable outcome of patients with CAD.

Rare retinal haemorrhages in translational accidental head trauma in children

PURPOSE: The characteristic findings in accidental head injury consist of linear skull fracture, epidural haematoma, localized subdural haematoma, or cortical contusion because of a linear or translational impact force. Retinal haemorrhages have been found, although uncommon, in accidental head trauma. METHODS: We performed a retrospective study of 24 consecutive cases of children with severe head injuries caused by falls. Inclusion criteria were skull fractures and/or intracranial haemorrhages documented by computerized tomography. All patients underwent a careful ophthalmic examination including dilated indirect fundoscopy within the first 48 h following admission. RESULTS: No retinal haemorrhages could be found in patients whose accidents were plausible and physical and imaging findings were compatible with reported histories. Excessive bilateral retinal haemorrhages were found in only three children with the typical signs of shaken baby syndrome. In eight children, trauma had led to orbital roof fractures. CONCLUSIONS: Retinal haemorrhages were not found in any of the patients with accidental trauma despite the severity of their head injuries. Hence, we add more evidence that there are strong differences between the ocular involvement in accidental translational trauma and those in victims of non-accidental trauma. Fall-related injuries carry a very low risk of retinal haemorrhages.

Aspirin vs anticoagulation in carotid artery dissection: a study of 298 patients

BACKGROUND: No randomized study has yet compared efficacy and safety of aspirin and anticoagulants in patients with spontaneous dissection of the cervical carotid artery (sICAD). METHODS: Prospectively collected data from 298 consecutive patients with sICAD (56% men; mean age 46 +/- 10 years) treated with anticoagulants alone (n = 202) or aspirin alone (n = 96) were retrospectively analyzed. Admission diagnosis was ischemic stroke in 165, TIA in 37, retinal ischemia in 8, and local symptoms and signs (headache, neck pain, Horner syndrome, cranial nerve palsy) in 80 patients, while 8 patients were asymptomatic. Clinical follow-up was obtained after 3 months by neurologic examination (97% of patients) or structured telephone interview. Outcome measures were 1) new cerebral ischemic events, defined as ischemic stroke, TIA, or retinal ischemia, 2) symptomatic intracranial hemorrhage, and 3) major extracranial bleeding. RESULTS: During follow-up, ischemic events were rare (ischemic stroke, 0.3%; TIA, 3.4%; retinal ischemia, 1%); their frequency did not significantly differ between patients treated with anticoagulants (5.9%) and those treated with aspirin (2.1%). The same was true for hemorrhagic adverse events (anticoagulants, 2%; aspirin, 1%). New ischemic events were significantly more frequent in patients with ischemic events at onset (6.2%) than in patients with local symptoms or asymptomatic patients (1.1%). CONCLUSIONS: Within the limitations of a nonrandomized study, our data suggest that frequency of new cerebral and retinal ischemic events in patients with spontaneous dissection of the cervical carotid artery is low and probably independent of the type of antithrombotic treatment (aspirin or anticoagulants).

Cerebral extension of steroid-responsive meningitis arteritis in a boxer

A comatose 30-month-old, entire male boxer was presented because of an acute history of a cluster of three to four seizures. Neurological examination suggested a diffuse to multifocal intracranial lesion. Magnetic resonance tomography revealed symmetrical multifocal to diffuse changes of the cerebral grey matter and ependymal lining with sediment in the lateral ventricles. Haematological examination revealed leucocytosis with neutrophilia. Cerebrospinal fluid examination revealed high protein concentration and polymorphonuclear pleocytosis. Despite antiepileptic treatment, therapy against increased intracranial pressure and antibiosis, the dog's condition continued to deteriorate and he was euthanased. Pathological examination revealed fibrinosuppurative meningo-ependymitis and necrotising arteritis throughout the brain. In addition, chronic inflammation and arterial stenosis was found in the spinal meninges. No infectious agent was found. A diagnosis of steroid-responsive meningitis arteritis was made. The massive extension into the meninges and ventricular system of the forebrain has not been described previously in dogs with steroid-responsive meningitis arteritis and should be considered in the differential diagnosis when an intracranial suppurative infection is suspected.

Antiplatelets versus Anticoagulants for the Treatment of Cervical Artery Dissection: Bayesian Meta-Analysis

OBJECTIVE To compare the effects of antiplatelets and anticoagulants on stroke and death in patients with acute cervical artery dissection. DESIGN Systematic review with Bayesian meta-analysis. DATA SOURCES The reviewers searched MEDLINE and EMBASE from inception to November 2012, checked reference lists, and contacted authors. STUDY SELECTION Studies were eligible if they were randomised, quasi-randomised or observational comparisons of antiplatelets and anticoagulants in patients with cervical artery dissection. DATA EXTRACTION Data were extracted by one reviewer and checked by another. Bayesian techniques were used to appropriately account for studies with scarce event data and imbalances in the size of comparison groups. DATA SYNTHESIS Thirty-seven studies (1991 patients) were included. We found no randomised trial. The primary analysis revealed a large treatment effect in favour of antiplatelets for preventing the primary composite outcome of ischaemic stroke, intracranial haemorrhage or death within the first 3 months after treatment initiation (relative risk 0.32, 95% credibility interval 0.12 to 0.63), while the degree of between-study heterogeneity was moderate (τ(2) = 0.18). In an analysis restricted to studies of higher methodological quality, the possible advantage of antiplatelets over anticoagulants was less obvious than in the main analysis (relative risk 0.73, 95% credibility interval 0.17 to 2.30). CONCLUSION In view of these results and the safety advantages, easier usage and lower cost of antiplatelets, we conclude that antiplatelets should be given precedence over anticoagulants as a first line treatment in patients with cervical artery dissection unless results of an adequately powered randomised trial suggest the opposite.