Rupture Of Arteriovenous Malformation Research Articles

1654 – Efficacy of aripiprazole on behavioural symptoms in three young patients with severe acquired brain injury

The atypical antipsychotic drug aripirprazole has a partial agonist activity on the dopamine receptors. This characteristic makes aripiprazole different from other antipsychotic agents. In this paper, we aim to describe the use of this drug in the management of three young patients with acquired brain injury: a woman with Wilsons disease, a male with a rupture of an arteriovenous malformation and a male with severe traumatic brain injury. All patients presented behavioural symptoms. One of them presented frequent crises of psychomotor agitation with strong physical aggressive reaction, partial awareness and low frustration tolerance. The other two patients reported a prevalence of negative symptoms, as inactivity, apathy, lack of will and severe perseveration. They were referred to our Unit and were evaluated with a full functional assessment at the moment of admission and at the discharge, depending on their clinical picture. The evaluation included: MMSE (Mini Mental State Examination), LCF (Level of Cognitive Functioning), DRS (Disability Rating Scale) and FIM (Functional Independence Measure). The behavioural assessment was made with clinical interviews. After the introduction of aripiprazole, we found an improvement in the behavioural pattern, moreover neuropsychological and motor evaluation appeared not affected. These results suggest that the use of aripiprazole in patients with acquired brain injury is suitable for its efficacy in reducing psychotic and behavioural symptoms but also for its potential for not affecting motor and cognitive functioning.

Predictive morphological factors of rupture of arteriovenous malformations of the brain

The study includes a series of 39 patients with AVM of the brain that are not subjected to any method of treatment, except for the symptomatic treatment who were hospitalized and diagnosed AVM at the Institute of Neurosurgery, Clinical Center, in the period 2005-2011. Results: The structure of the patients was measured by gender are male. Average age of the respondents was 27.4 ? 7.6 years. With the average length of the follow-up of 4.8 years, new hemorrhage occurred in 24 patients (58 episodes). Predictor (p<0.01), factors for bleeding include: arterial supply from the VB and ACA basin and multiple arterial supply. Conclusion: The analysis of our series may be proposed for following model of the natural course of AVM : After initiall haemorrhage there is annual risk of rehemorrhage of 3.33%. Bleeding events were significantly more common in medium-sized AVM (2.5 - 5 cm), localized in elocvent area of the brain with combined type of venous drainage, arterial supply from the vertebrobasilar artery, anterior cerebral artery basin or combined arterial supply.

The Lessons Learned from Three Cases of Islet Autotransplantation with a Severe Inflammatory Status Due to a Rupture of a Pancreatic Arteriovenous Malformation

Objective: Although many studies on islet autotransplantation for the treatment of chronic pancreatitis have so far been reported, there have only been a few reports regarding islet autotransplantation for the treatment of acute pancreatitis with severe inflammation. In patients demonstrating a severe inflammatory status, islet autotransplantation usually fails due to both an insufficient islet yield and an impaired islet quality. Therefore, it is important to both identify such cases and improve the treatment protocol in order to increase the success of this therapeutic approach. In the present study, we experienced three cases of islet autotransplantation who all had a severe inflammatory status due to a rupture of a pancreatic arteriovenous The Lessons Learned from Three Cases of Islet Autotransplantation with a Severe Inflammatory Status Due to a Rupture of a Pancreatic Arteriovenous Malformation malformation, and we established a novel graft protection protocol to more effectively treat such patients. Methods: Total pancreatectomy and islet autotransplantation were performed in 3 males diagnosed with a pancreatic arteriovenous malformation. An emergency operation was performed on 2 of these cases due to a rupture and bleeding from the mass. The pancreas weight was 54, 186, and 86 g, respectively. The pancreatic islets were isolated using a modified Ricordi method. The inhalation of isoflurane during islet infusion and continuous intensive insulin treatment combined with shortterm fasting/total parenteral nutrition during the avascular period of the grafts (10 days) were carried out in order to allow the islet grafts to rest. Results: The islet yield was 355,270, 244,758, and 310,238 islet equivalents, respectively, but only 229,538 islet equivalents were infused due to catheter trouble in the third case. The total tissue volume was 5.7, 16.0, and 1.0 ml, respectively. After certifying that no bacterial contamination existed, the islets were then transplanted via the portal vein. In the second case, a sudden increase in the portal vein pressure was seen during islet infusion, and then a portal embolism was observed over a wide range of the liver. As a result, a surgical embolectomy and embolytic therapy were performed. In the other 2 cases, the blood glucose of the recipients was well maintained with no sign of hypoglycemia, and a substantial level of fasting C-peptide was observed under a low dose of daily insulin supplementation. The SUIT index of the first case (15-27) was considerably higher than that of the third case (6-10), thus suggesting that the transplanted islet amount and/or the transplanted tissue amount may play an important role in the treatment outcome. Of particular note, no recurrence of the arteriovenous malformation in all the cases has so far been seen at the transplanted site. Conclusions: These data suggest that the above described refined islet isolation procedures combined with a novel graft protecting protocol could play an important role in achieving successful islet autotransplantation in patients with a severe inflammatory status. Furthermore, several modifications, including changes in the catheterization procedures, reducing the graft amount, and switching to either cultured-islet transplantation or intramascular islet transplantation make need to be performed when complications such as unexpected copious bleeding or a suture of the portal vein occurs.

Persistent Hemodynamic Changes in Ruptured Brain Arteriovenous Malformations

Hemodynamic properties of brain arteriovenous malformations (AVMs) with risk factors for a future hemorrhage are essentially unknown. We hypothesized that AVMs with anatomic properties, which are associated with an increased rupture risk, exhibit different hemodynamic characteristics than those without these properties. Seventy-two consecutive patients with AVMs diagnosed by conventional angiography underwent MRI examination, including time-resolved 3-dimensional MR angiography. Signal-intensity curves derived from the time-resolved 3-dimensional MR angiography datasets were used to calculate relative blood flow transit times through the AVM nidus based on the time-to-peak parameter. For identification of characteristics associated with altered transit times, a multiple normal regression model was fitted with stepwise selection of the following regressors: intracranial hemorrhage, deep nidus location, infratentorial location, deep drainage, associated aneurysm, nidus size, draining venous stenosis, and number of draining veins. A previous intracranial hemorrhage is the only characteristic that was associated with a significant alteration of the relative transit time, leading to an increase of 2.4 seconds (95% CI, 1.2-3.6 seconds;, P<0.001) without adjustment and 2.1 seconds (95% CI, 0.6-3.6 seconds; P=0.007) with adjustment for all other regressors considered. The association was independent of the bleeding age. Hemodynamic parameters do not seem useful for risk assessment of an AVM-related hemorrhage because only a previous AVM rupture leads to a significant and permanent alteration of the hemodynamic situation.

Relationships between hemorrhage, angioarchitectural factors and collagen of arteriovenous malformations.

While associations between the angioarchitecture of arteriovenous malformations (AVMs) in the brain and pathological features have been described, here we investigated the relationship between the angioarchitecture, the pathological features of the vessel wall, and hemorrhagic events. The study was conducted on 43 patients: 16 with ruptured AVM (rAVM), 15 with non-ruptured AVM (nrAVM), 6 with craniocerebral trauma (control) and 6 with epilepsy (control). The diagnosis of AVM was confirmed by preoperative digital subtraction angiography. Tissues were stained with hematoxylin and eosin and Masson's trichrome (for collagen fibers) to evaluate the vessel wall structure and endothelial integrity. The content and distribution of collagen types I and III in the vessel wall were assessed by immunohistochemical staining. In the nrAVM group, the nidus had more draining veins than the rAVM group (P <0.05). Severely damaged endothelial cells, significantly fewer smooth muscle cells in the media, and hyperplasic type-I and -III collagen fibers were found in the rAVM group. The content of collagen types I and III in rAVMs was higher than that in the nrAVM (P <0.05) and control groups (P <0.01). There is an association between angioarchitectural features such as the number of draining veins and the pathological structure of the AVM wall. These abnormalities may contribute to AVM rupture.

Haemorrhagic Strokes in Pregnancy and Puerperium

There is an increased risk of strokes in pregnancy and puerperium. Intracranial haemorrhage is the rarer of the two stroke subtypes but carries a greater morbidity and mortality for both the mother and the child. This review highlights the causes of pregnancy-related intracranial haemorrhage and its management. The incidence varies from region to region with the highest being reported from China and Taiwan. Majority of these haemorrhages are secondary to hypertensive disorders of pregnancy with smaller proportions related to aneurysm and arteriovenous malformation rupture. A small but important contributor is cortical venous thrombosis which, although predominantly gives rise to ischaemic lesions, may lead to parenchymal haemorrhages as well. Presentation is usually with headaches or seizures, with or without focal deficits. Diagnosis requires brain imaging with computerized tomography or magnetic resonance imaging, and the necessity of investigation when this diagnosis is suspected supersedes the small risk of fetal malformation. Management follows the general management principles for intracranial haemorrhage management. Blood pressures need to be strictly monitored and medicines used for controlling them may differ slightly due to teratogenic effects. For preeclampsia, early but safe delivery is the best treatment. For cortical venous thrombosis, low-molecular-weight heparin is the preferred agent. Aneurysms and vascular malformations need to be definitively treated to prevent re-bleed and this can be achieved through surgical or endovascular procedures. The timing of surgery depends on neurosurgical considerations. However, the timing and mode of delivery are governed by obstetric factors. Risk of future haemorrhage depends on whether the underlying aetiology can be and has been definitively treated.

Management of non-traumatic intraventricular hemorrhage

Intraventricular hemorrhage (IVH) is defined as the eruption of blood in the cerebral ventricular system and is mostly secondary to spontaneous intracerebral hemorrhage and aneurysmal and arteriovenous malformation rupture. IVH is a proven risk factor of increased mortality and poor functional outcome. Its seriousness is correlated not only with the amount of blood but also with the involvement of the third and fourth ventricles. There are four mechanisms that explain the pathophysiology of this event: acute obstructive hydrocephalus, the mass effect exerted by the blood clot, the toxicity of blood-breaking products on the adjacent brain parenchyma, and, lastly, the development of a chronic hydrocephalus. It is thus obvious that the clearance of blood from the ventricles should be a therapeutic goal. In cases of acute hydrocephalus, external ventricular drainage is a mandatory step, but proven often insufficient. The concomitant use of intraventricular fibrinolytics such as recombinant tissue plasminogen activator or urokinase seems to be beneficial at least in the context of spontaneous intracerebral hemorrhage, in which their use is now accepted but not yet validated by a randomized trial. Given the potential neurotoxicity of these agents, further research is needed in order to identify the best treatment for intraventricular fibrinolysis (IVF). The endoscopic retrieval of intraventricular blood was also described recently and seems to be as efficient as IVF, but its use is limited to specialized centers. IVH represents a therapeutic challenge for neurosurgeons, neurologists, and intensivists. Thus, a better understanding of this dramatic event will help in better tailoring the treatment strategies.

Retrospective analysis of brain structural changes in early terms of nontraumatic intracranial hemorrhage and prognosis of disease course

Introduction. Nontraumatic intracranial hemorrhage (NIH) is not only medical but important social problem because of disease prevalence, it’s severity and high lethality rate. The hemorrhage centers as a rule arise in area of a. cerebri media, frequently at uncontrollable arterial hypertension, rupture of arterial aneurisms and arteriovenous malformations.Materials and methods. Structural features of NIH were estimated in 162 patients, died because of arterial aneurisms or arteriovenous malformations rupture, taking into consideration their structural features. The role of morphological changes in pathogenesis of secondary changes at NIH, depending on their centers localization and duration of treatment, was defined. Main pathogenetic chains links of a thanatogenesis were defined.Results. At hematomas in the zone of capsula interna and subcortical knots а cavity filled with liquid and blood parcels is formed. The area of hemorrhagic impregnation arises due to it’s small centers coalescence, it has no clear border and characterized by brain tissue flaccid consistence, impregnated with blood elements. In acute period of hemorrhagic NIH secondary diffuse and focal changes of brain tissue are observed, in their realization both pathogenetic, and sanogenic factors, referred to isolation of areas of necrosis by vascular reactions and an inflammation, play a significant role.However blood flow retardation owing to coagulation disturbances and brain edema at their inadequate expression and a long exposition can cause neurons’ death not only on border of primary damage, but also on a distance that can lead to fatal consequences.Conclusions. NIH, caused by arterial aneurysms or malformations rupture is accompanied by considerable secondary changes of brain tissue around the hemorrhage centers that breaks functions of many organs and systems, frequently with fatal consequences. In-timed diagnostics of secondary structural changes of brain tissue and prevention of their emergence are based on complex theoretical studying of this problem and are possible under use of complex of clinical, neurovisualizing and retrospective morphological researches. The obtained results allow to define certain links of cerebrovascular disease pathogenesis, show importance of in-timed neurosurgical help, and expand representations concerning thanatogenesis at NIH.

Use of endovascular embolization to treat a ruptured arteriovenous malformation in a pregnant woman: a case report

IntroductionPregnancy has been linked to increased rates of arteriovenous malformation rupture. This link remains a matter of debate and very few studies have addressed the management of arteriovenous malformation in pregnancy. Unruptured arteriovenous malformations in pregnant woman generally warrant conservative management due to the low rupture risk. When pregnant women present with ruptured arteriovenous malformation, however, surgery is often indicated due to the increased risk of re-rupture and associated mortality. Endovascular embolization is widely accepted as an important component of contemporary, multimodal therapy for arteriovenous malformations. Although rarely curative, embolization can facilitate subsequent surgical resection or radiosurgery. No previous reports have been devoted to the endovascular management of an arteriovenous malformation in a pregnant woman.Case presentationA 23-year-old Caucasian woman presented with headache and visual disturbance after the rupture of a left parieto-occipital arteriovenous malformation in the 22nd week of her pregnancy. After involving high-risk obstetric consultants and taking precautions to shield the fetus from ionizing radiation, we proceeded with a single stage of endovascular embolization followed soon after by open surgical resection of the arteriovenous malformation. There were several goals for the angiography in this patient: to better understand the anatomy of the arteriovenous malformation, including the number and orientation of feeding arteries and draining veins; to look for associated pre-nidal or intra-nidal aneurysms; and to partially embolize the arteriovenous malformation via safely-accessible feeders to facilitate surgical resection and minimize blood loss and operative morbidity.ConclusionFrom our experience and review of the literature, we maintain that ruptured arteriovenous malformations in pregnancy may be managed in a similar manner to those in non-gravid women. Precautions should be taken to reduce the operative time and exposure of the fetus to ionizing radiation and contrast agents.

Radiotherapy for AVM-related epilepsy

The majority of cerebral arteriovenous malformations (AVM) detected in the United States are diagnosed unruptured and among those, epileptic seizures constitute the most common clinical presentation in otherwise asymptomatic patients.1 Recent population-based data suggest the 5-year incidence of first-ever seizures after AVM diagnosis is about 8%, but may increase to 23% after eventual AVM rupture during follow-up.2 Other AVM-specific predictors of seizures include increasing AVM size, frontal lobe and arterial border zone location, and the presence of superficial drainage.3 Similar to headaches, AVM-related seizures may disappear,4 worsen,5 or remain the same after successful interventional therapy.6 Nonetheless, systematic follow-up studies on seizure activity after AVM eradication are rare.

Silent Intralesional Microhemorrhage as a Risk Factor for Brain Arteriovenous Malformation Rupture

We investigated whether brain arteriovenous malformation silent intralesional microhemorrhage, that is, asymptomatic bleeding in the nidal compartment, might serve as a marker for increased risk of symptomatic intracranial hemorrhage (ICH). We evaluated 2 markers to assess the occurrence of silent intralesional microhemorrhage: neuroradiological assessment of evidence of old hemorrhage-imaging evidence of bleeding before the outcome events-and hemosiderin positivity in hematoxylin and eosin-stained paraffin block sections. We identified cases from our brain arteriovenous malformation database with recorded neuroradiological data or available surgical paraffin blocks. Using 2 end points, index ICH or new ICH after diagnosis (censored at treatment, loss to follow-up, or death), we performed logistic or Cox regression to assess evidence of old hemorrhage and hemosiderin positivity adjusting for age, sex, deep-only venous drainage, maximal brain arteriovenous malformation size, deep location, and associated arterial aneurysms. Evidence of old hemorrhage was present in 6.5% (n=975) of patients and highly predictive of index ICH (P<0.001; OR, 3.97; 95% CI, 2.1-7.5) adjusting for other risk factors. In a multivariable model (n=643), evidence of old hemorrhage was an independent predictor of new ICH (hazard ratio, 3.53; 95% CI, 1.35-9.23; P=0.010). Hemosiderin positivity was found in 36.2% (29.6% in unruptured; 47.8% in ruptured; P=0.04) and associated with index ICH in univariate (OR, 2.18; 95% CI, 1.03-4.61; P=0.042; n=127) and multivariable models (OR, 3.64; 95% CI, 1.11-12.00; P=0.034; n=79). The prevalence of silent intralesional microhemorrhage is high and there is evidence for an association with both index and subsequent ICH. Further development of means to detect silent intralesional microhemorrhage during brain arteriovenous malformation evaluation may present an opportunity to improve risk stratification, especially for unruptured brain arteriovenous malformations.

Use of the Valsalva Maneuver in Addition to Controlled Hypotension During Endovascular AVM Embolization: A Novel Approach to Reducing Distal Particle Embolization?

Study Objective: To report the use of a sustained Valsalva maneuver during deliberate hypotension in order to reduce the incidence of distal particle embolization during the neuroangiographic embolization of intracranial arteriovenous malformations (AVMs). Design: Retrospective case series. Patients: 54 cases were studied involving 46 unique patients (20 male, 26 female) seen between January 1, 2007 and December 31, 2008. All patients were ASA class II-III and were undergoing neuroangiographically-assisted embolization for intracranial AVMs. Intervention: Immediately prior to the injection of the embolic substance, each patient received a dose of nitroglycerin to lower their systolic blood pressure from baseline (112146 mm Hg) to a target of 55 mm Hg. Next, mechanical ventilation was suspended and manual pressure was applied to the ventilation bag of the anesthesia circuit to maintain a constant airway pressure of 20 cm H2O. This simulated Valsalva maneuver was maintained for 15 seconds after the injection of the embolic material, at which point mechanical ventilation was resumed. Main Results: All patients tolerated the deliberate hypotension/Valsalva protocol well. 2 patients experienced a rupture of the AVM during the procedure. Case Study British Journal of Medicine & Medical Research, 2(3): 444-453, 2012 445 Conclusions: The distal embolization of the embolic material during intracranial AVM embolization is a potentially fatal complication of this procedure. Although our results represent a small case series, they suggest that the use of deliberate arterial hypotension in addition to a simulated Valsalva maneuver may enhance the safety and efficacy of intracranial AVM embolization. Further study, with rigorous control standards and monitoring, is warranted.

The neural correlates of impaired collision avoidance in hemianopic patients

The aim of this study was to assess the brain regions associated with impaired performance in a virtual, dynamic collision avoidance task, in a group of patients with homonymous visual field defects (HVFDs) because of unilateral vascular brain lesions. Overall task performance was quantitatively assessed as the number of collisions while crossing an intersection at two levels of traffic density. Twenty-six patients were divided into two subgroups using the median split method: patients with 'performance above average' (HVFD(A), i.e. lower number of collisions) and patients with 'performance below average' (HVFD(B), i.e. higher number of collisions). In order to identify the anatomical structures that might be specifically affected in HVFD(B) patients but spared in HVFD(A) patients, overlap, subtraction and voxel-based lesion-symptom mapping analyses were performed using the MRIcron software. No significant difference in collision avoidance between patients with left- and right-hemispheric lesions was revealed. Separate lesion analysis in 12 patients with right- and 14 patients with left-hemispheric lesions showed that the cortical structures associated with impaired collision avoidance were the parieto-occipital region and posterior cingulate gyrus in the right hemisphere and the inferior occipital cortex and parts of the fusiform (occipito-temporal) gyrus in the left hemisphere. In the present collision avoidance paradigm, impaired performance of patients with right-hemispheric lesions is associated with damage in the dorsal processing stream and potential impact on the visual spatial working memory (WM), while impaired performance of patients with left-hemispheric lesions is associated with damage in the ventral stream and potential impact on the visual object WM.

Decision-Making in the Scheduling of Endovascular Treatment after Brain Arteriovenous Malformation Haemorrhage: A Retrospective Single Centre Study

The appropriate timing for endovascular intervention after brain arteriovenous malformation (bAVM) rupture is not known. This paper aims to determine factors that lead to early endovascular intervention and to investigate whether early intervention has the same complication rate as late intervention in a single centre. All patients who underwent endovascular treatment for a ruptured bAVM at our institution in the period January 2007 and July 2010 were included in this retrospective observational study. Of 50 patients, 33 had early endovascular intervention, defined as within 30 days of haemorrhage and the remaining 17 patients had endovascular treatment at day 30 or beyond. A greater proportion of patients treated within the first 30 days were in neuro-intensive care preoperatively (51.5% vs. 23.5%, p=0.07). A 'high-risk' angioarchitectural feature was identified in more patients who had acute intervention (78.8% vs. 11.8%, p<0.0001) and targeted embolization was also more frequent in this group (48.5% vs. 5.9%, p=0.004). Nidal aneurysms, venous varices and impaired venous outflow (venous stenosis) were the principal 'high risk' features. Clinically apparent complications occurred in 10.8% of procedures with permanent neurological deficit in 3.6%. There was no directly procedure-related mortality. There was no statistically significant difference in the complication rate of early procedures compared with delayed interventions (12.5% vs. 7.4%, p=0.71). Greater initial injury severity and the presence of high-risk lesion characteristics are the factors that lead to early endovascular intervention. Early intervention is associated with a higher complication rate, but this difference is not statistically significant.

Internal cerebral veins varix due to midline arteriovenous malformation: how much is the risk of bleeding?

We report a case of 40-year-old sportsman admitted to our department for a generalized seizure associated with bladder and bowel incontinence occurred during exercise. The patient quickly regained consciousness without postcritical deficits. Neurological examination appeared completely normal. A head computer tomography (CT) scan showed a midline arteriovenous malformation (AVM) without the evidence of bleeding (Fig. 1a, b). A digital subtraction angiography revealed a dysplastic nidus fed by branches of bilateral internal–external carotid and vertebrobasilar arteries, and draining both in the superficial and deep venous system, which showed varicose dilatation with Galen’s vein stenosis (Fig. 1c–g). Cerebral varix is defined as an ectasia which doubles vein diameter. It can be due to an arteriovenous shunt and appears more common in patients with direct fistulas, than in cerebral AVM with dysplastic nidi [1]. Differently from those associated with Galen’s vein fistulae, huge intracranial varix associated with cerebral AVMs were seldom reported. Headache, bruit, focal mass effect and hydrocephalus are common presentation symptoms [2]. Intracranial haemorrhage has been instead less often reported at clinical onset [3]. In the most of the cases of giant varix, direct arteriovenous communications in the context of nidus were observed, especially between feeding arteries and the varicose veins [4]. This discrete angiographic finding separate these vascular malformations from the classical and more common AVMs in which an abnormal vascular network is identified between the arterial feeders and draining veins [4]. Venous hypertension with retrograde drainage often results in focal neurological deficits and seizures [1]. Although it is commonly assumed that venous ectasia increases the bleeding risk, varix haemorrhagic presentation has been rarely reported [4]. It is may be due to the progressive thickening of the arterialized veins wall, with intimal proliferation of synthetic smoothmuscle cells and disappearance of the internal elastic lamina, that make arterialized veins not greatly prone to rupture [1, 4]. On the other hand, instead, the presence of venous varix on the draining veins has been recognized as a factor increasing the risk of haemorrhage in dural arteriovenous fistulae [5]. In the case reported here, the presence of multiple feeders causing high flow shunt rate, direct drainage in a cisternal venous system, and an impaired venous outlet due to the Galen’s vein stenosis, may have contributed to the varix formation. Prolonged sporting activity, instead, has not been a factor influencing AVM rupture.

Hypovolemic Shock Caused by an Abrupt Rupture of Giant Renal Arteriovenous Malformations

Hypovolemic Shock Caused by an Abrupt Rupture of Giant Renal Arteriovenous Malformations

Re: "Comparison of 2 Approaches for Determining the Natural History Risk of Brain Arteriovenous Malformation Rupture"

We have with great interest read the article, ‘‘Comparison of 2 Approaches for Determining the Natural History Risk of Brain Arteriovenous Malformation Rupture,’’ by Kim et al. (1), published in the June 15, 2010, issue of the American Journal of Epidemiology. We agree with the authors that it is conceptually attractive to use age at the first arteriovenous malformation hemorrhage to assess the natural course of disease, and we published a paper using this concept in 1997 (2). However, as with all evaluations of retrospective data, the study by Kim et al. must be observed for the risk of selection bias. The use of life table statistics in this case is flawed with the lack of information from all patients that died from the initial hemorrhage, before reaching the hospital, and also in cases where the arteriovenous malformation is not diagnosed. We therefore preferred an analytical approach, using the age distribution at first hemorrhage rather than life table statistics to elucidate the annual risk for hemorrhage from these lesions (2). This has the advantage of being insensitive to the relation between arteriovenous malformations that have or have not bled. It can also be used to calculate the age dependence, if such exists. However, assessment of the annual risk is accurate only if the assumption of arteriovenous malformation’s being a congenital condition is correct. If so, there is an unambiguous relation between the age distribution of the age at first hemorrhage and the risk for hemorrhage. If not, the calculated risk is lower than the true annual risk for hemorrhage. Furthermore, it implies that an insignificant number of patients develop an arteriovenous malformation after the peak of the age distribution, that is, later than 25 years of age in our material. The most important finding in our study was the strong relation between age and risk for arteriovenous malformation rupture, the risk increasing with increasing patient age. It would be very interesting to combine the patient materials and further analyze the important question of the natural course of brain arteriovenous malformations.

Effective Treatment With Clozapine and Valproate for Refractory Schizophrenia-Like Psychosis After Cerebellar Hemorrhage

The cerebellum has traditionally been regarded as an organ of motor coordination. However, the importance of the cerebellum in psychiatric disorders, behavior, and cognition is increasingly being recognized. There is no consensus concerning treatment of schizophrenia-like psychosis after cerebellar pathology. Reports describe the use of several antipsychotics, either alone or in combination with antidepressants or lithium. Clozapine is used for the treatment of refractory schizophrenia, but there are no reports of its use in the above-mentioned situation. We report the case of a 20-year-old woman who developed a schizophrenia-like psychosis after rupture of arteriovenous malformation at 13 years of age. The psychotic symptoms proved to be resistant to treatment, and several psychopharmacological schemas were tried. The clinical picture only showed consistent improvement with the combined use of clozapine and valproate. The relationship between chronic psychosis and cerebellar pathology remains poorly understood. Cases like the present one suggest that clozapine and valproate may be used safely and effectively in refractory schizophrenia-like psychosis associated with cerebellar pathology.

An Easy Performed Sit-to-Stand Test for the Patient with Cerebella Arteriovenous Malformation rupture: A Case Report

An Easy Performed Sit-to-Stand Test for the Patient with Cerebella Arteriovenous Malformation rupture: A Case Report

Intraventricular Hemorrhage Secondary to Intranidal Aneurysm Rupture—Successful Management by Arteriovenous Malformation Embolization Followed by Intraventricular Tissue Plasminogen Activator: Case Report

Intraventricular hemorrhage related to arteriovenous malformation (AVM) rupture is associated with significant morbidity and mortality. Intraventricular tissue plasminogen activator (tPA) has been used to treat spontaneous intraventricular hemorrhage. We demonstrate the successful application of endovascular occlusion to seal the rupture site of an AVM followed by intraventricular tPA. A 32-year-old woman presented with a right frontoparietal parasagittal AVM abutting the motor cortex. The AVM was diagnosed when the patient was 13 years old, and she initially underwent conservative management. At the age of 30, the patient suffered an intracranial hemorrhage, leaving her with left hemiparesis. After rehabilitation, the patient regained ambulation; however, she remained spastic and hyperreflexic on the left side. Two years after her major hemorrhage, she presented for elective treatment of her AVM. The patient was advised to undergo staged embolization before surgical resection of her AVM. The initial embolization was uneventful. A second embolization was complicated by intraventricular hemorrhage and coma. The patient was treated with placement of an external ventricular drain followed by embolization of intranidal aneurysm. After embolization of the intranidal aneurysm the ruptured, the patient was treated with intraventricular tPA. The patient had rapid clearance of the intraventricular hemorrhage and significant improvement in her neurological examination, following commands 24 hours later and returning almost to baseline. This case demonstrates the feasibility of treating AVM-related intraventricular hemorrhage with tPA if the rupture source can be confidently sealed interventionally. This strategy can be lifesaving but needs further study to ensure its safety.