Acute Obstructive Hydrocephalus Research Articles

Acute hydrocephalus triggered by isolated traumatic subarachnoid hemorrhage in the posterior fossa following mandibular fracture in a toddler: a rare case report.

Facial bone fractures triggered by low-height falls are rare in toddlers, while severe intracranial injuries resulting from minor trauma are extremely rare. Herein, we report the case of a 2-year-old girl who fell from a baby chair, striking her chin, who rapidly developed impaired consciousness 3h later. The patient subsequently presented with a mandibular fracture and acute obstructive hydrocephalus due to a traumatic isolated subarachnoid hemorrhage in the posterior cranial fossa. She was successfully treated with ventricular drainage, which achieved a favorable outcome. Maxillofacial trauma and head injuries are closely associated. Even in minor cases of maxillofacial trauma, vigilant monitoring and prompt intervention are crucial to prevent fatal outcomes in toddlers.

Clinical features and treatment of apoplectic intratumoral hemorrhage of glioma

ObjectiveThe primary objective of this study was to explore the clinical characteristics of apoplectic intratumoral hemorrhage in gliomas and offer insights for improving the diagnosis and treatment of this disease.MethodsWe analyzed the clinical data of 35 patients with glioma and hemorrhage. There were eight cases of multiple cerebral lobe involvement, and 22 cases involved a single lobe. Twenty-one patients had a preoperative Glasgow Coma Scale (GCS) score of ≥ 9 and had a craniotomy with tumor resection and hematoma evacuation after undergoing preoperative preparation. A total of 14 patients with GCS < 9, including one with thalamic hemorrhage breaking into the ventricles and acute obstructive hydrocephalus, underwent craniotomy for tumor resection after external ventricular drainage (EVD). One patient had combined thrombocytopenia, which was surgically treated after platelet levels were normalized through transfusion. The remaining 12 patients received immediate intervention in the form of craniotomy hematoma evacuation and tumor resection.ResultsWe performed subtotal resection on three tumors of thalamic origin and two tumors of corpus callosum origin, but we were able to successfully resect all the tumors in other locations that were gross total resection Pathology results showed that 71.43% of cases accounted for WHO-grade 4 tumors. Among the 21 patients with a GCS score of ≥ 9, two died perioperatively. Fourteen patients had a GCS score < 9, of which eight patients died perioperatively.ConclusionsPatients with a preoperative GCS score ≥ 9 who underwent subemergency surgery and received aggressive treatment showed a reasonable prognosis. We found their long-term outcomes to be correlated with the pathology findings. On the other hand, patients with a preoperative GCS score < 9 required emergency treatment and had a high perioperative mortality rate.

Endoscopic Third Ventriculostomy and Pineal Biopsy from a Single Entry Point.

Pineal neoplasms have a significant impact on children although they are relatively uncommon. They account for approximately 3-11% of all childhood brain tumors, which is considerably higher than the <1% seen in adult brain tumors. These tumors can be divided into three main categories: germ cell tumors, parenchymal pineal tumors, and tumors arising from related anatomical structures. Obtaining an accurate and minimally invasive tissue diagnosis is crucial for selecting the most appropriate treatment regimen for patients with pineal gland tumors. This is due to the diverse treatment options available and the potential risks associated with complete resection. In cases where patients present with acute obstructive hydrocephalus caused by a pineal gland tumor, immediate treatment of the hydrocephalus is necessary. The urgency stems from the potential complications of hydrocephalus, including increased intracranial pressure and neurological deficits. To address these challenges, a minimally invasive endoscopic approach provides a valuable opportunity. This technique allows clinicians to promptly relieve hydrocephalus and obtain a histological diagnosis simultaneously. This dual benefit enables a more comprehensive understanding of the tumor and assists in determining the most effective treatment strategy for the patient.

Acute Obstructive Hydrocephalus and Acute Cerebellar Ischemic Stroke as a Complication of Takayasu Arteritis in a Young Male Patient: A Rare Case Report

Introduction: Takayasu arteritis is a rare type of vasculitis associated with various neurological manifestations. Multiple components, including thrombosis, embolism, stenosis, and vascular inflammation, are involved in the underlying pathophysiology. Case Presentation: A 21-year-old male patient presented with vomiting, difficulty speaking, disorientation, and seizures. On examination, pinpoint pupils and blood pressure discrepancies among four limbs were noted. Imaging findings supported the diagnosis of acute obstructive hydrocephalus, acute cerebellar infarction, and Takayasu arteritis. The patient was treated with IV antibiotics and steroids and underwent a ventriculoperitoneal shunt. Case discussion: Takayasu arteritis with cerebellar ischemia and obstructive hydrocephalus is quite a rare case. It presents with headache, dizziness, disorientation, and rarely with stroke. The diagnostic process includes computed tomography angiography (CTA) and imaging of the brain. It is mostly treated with pharmacological therapy; however, in some cases, surgery is required. Conclusion: This case highlights the rare but serious neurological adverse effects of Takayasu arteritis in young male patients, as well as the importance of interdisciplinary care. To prevent neurological degeneration, Takayasu arteritis patients must be identified and treated as soon as possible.

Jugulotympanic paraganglioma: A cause of sequential cranial nerve fallout and obstructive hydrocephalus

Abstract A 46-year-old male presented with a longstanding history of a sequential cranial nerve fallout. Following extensive imaging which included contrast enhanced computed tomography, computed tomography angiography, and diagnostic digital subtraction angiography, a diagnosis of jugulotympanic paraganglioma was made. The tumour was found to be locally invasive, encapsulating major neurovascular structures and ultimately inaccessible. Furthermore, the clinical presentation was complicated by acute obstructive hydrocephalus secondary to tumour mass effect. Given the rarity of the condition and unusually extensive presentation, neurosurgery alongside a multidisciplinary team collaborated to formulate a management plan aimed at maximizing functional outcome and minimizing intraoperative morbidity. A decision was made to perform palliative surgical debulking procedure followed by multidisciplinary care and rehabilitation. The patient demised in the care of his family prior to any further intervention.

Acute Obstructive Hydrocephalus: An Unexpected Cause of Cardiac Arrest

BackgroundEmergency physicians are well-versed in managing cardiac arrests, including the diagnostic and therapeutic steps after return of spontaneous circulation. Neurologic emergencies are a common cause of out-of-hospital cardiac arrest and must remain high in the differential diagnosis, as such cases often require specific interventions that may deviate from more common care pathways. Performing a noncontrast head computed tomography (NCHCT) scan after cardiac arrest has been found to change management, although the optimal timing of this imaging is unclear. Case ReportThis is the case of a young, pregnant woman who presented to the emergency department after cardiac arrest with return of spontaneous circulation in the prehospital setting. She was found to have acute obstructive hydrocephalus on NCHCT, which was later confirmed to be due to a previously undiagnosed colloid cyst of the third ventricle. This acute obstruction resulted in myocardial stunning and, ultimately, cardiac arrest. Although outcomes are often dismal when the cause of arrest is secondary to neurologic catastrophe, this patient survived with completely intact neurologic function. Why Should an Emergency Physician Be Aware of This?Although acute obstructive hydrocephalus due to a colloid cyst adjacent to the third ventricle is a rare condition, it is a potentially reversible neurologic cause of out-of-hospital cardiac arrest. However, positive outcomes depend on obtaining the diagnosis rapidly with neurologic imaging and advocating for neurosurgical intervention. This case supports the recommendation that emergency physicians should strongly consider post–cardiac arrest neurologic imaging when another cause is not immediately obvious.

Acute Complications of Pre-Resection CSF Diversion in Posterior Fossa Tumors with Hydrocephalus

Study background and significance: Posterior fossa tumors are a common pathology worldwide and often present with obstructive hydrocephalus. In the year 2021 CSF diversion for acute hydrocephalus from brain tumors was the most common performed emergency procedure in Tikur Anbessa hospital. It is a clinical dilemma choosing the mode of management for the hydrocephalus as it could be a lifesaving procedure but with a risk of unfortunate and devastating outcome. Objective: The aim of the study will be to evaluate the acute complications that occur with CSF diversion procedures that are done for obstructive hydrocephalus in the presence of posterior fossa mass before tumor resection. Method: It will be prospective observational study conducted at Tikur anbessa specialized hospital, which will be held from March 2021 up to October 2022. The research will involve all patients who have undergone CSF diversion procedure for obstructive hydrocephalus from posterior fossa tumors prior to tumor resection and patients will be followed for the first 48 hours post operatively. Patient’s presentation, nature of the posterior fossa tumor on imaging, post-operative clinical status and post op imaging will be taken to account. Result: In the study time frame of 18 months there were 89 patients who came with acute obstructive hydrocephalus from posterior fossa of which all underwent CSF diversion procedure before tumor resection. 52.8% were pediatrics and 47.2% where adults. The most common tumor location was vermian (31.5%) followed by cerebellar hemisphere (29.2%), 4th ventricular (25.8%) and the rest 9% account for cranial nerve and extra axial location. The largest tumor was 9.8cm but the median was 5.1cm. Based on the size they were categorized in to 3 groups, 71.9% were tumor size 4-6cm, 22.5% had a tumor size of &gt;6cm and there were 5.6% with tumor size &lt;4cm. Of the CSF diversion procedures performed 93.3% were VPS, EVD and ETV account for 3.4% each. All were followed for 48 hours post op and 8 patients had clinical deterioration after CSF diversion was done, and all patients with clinical deterioration underwent urgent non -contrast CT scan. They were found to have upward herniation, intra-tumoral bleeding, intraventricular hemorrhage or a combination of these findings. Of the 8 patients that deteriorated 5 died without successful resuscitation. The rest 3 improved and underwent definitive surgery. The risk for postoperative deterioration was 8.9% and 48-hour mortality was 5.6%. Variables were chosen to check association with the outcome (post-operative deterioration). Variables tested include age of the patient, tumor size and tumor location, all did not have statistically significant relationship with outcome (post-operative deterioration and 48-hour mortality). The association between the type of intervention and outcome could not be checked as there were not enough samples representing ETV/EVD performed, and majority (93.3%) were VPS. Conclusion: Through our research we tried to investigate the causes of acute deterioration after CSF diversion done for obstructive hydrocephalus from posterior fossa tumors by assessing the tumor size, location the type of intervention. Through our research we were not able to find any association from investigated factors and post-operative deterioration. Because of our limitation (the low number of sample size and not having enough number of ETV and EVD in the study population) we recommend further research is needed to have more information in this problem.

An Unusual Case of Posterior Fossa Predominant Posterior Reversible Encephalopathy Syndrome (PRES) Leading to Acute Hydrocephalus (P10-7.002)

<h3>Objective:</h3> To discuss acute hydrocephalus as an unusual complication of Posterior Reversible Encephalopathy Syndrome. <h3>Background:</h3> Posterior Reversible Encephalopathy Syndrome (PRES) is a well-recognized clinical and radiologic syndrome typically characterized by parieto-occipital vasogenic edema along with neurological symptoms, that improves after management or withdrawal of offending factor, in most cases being acute uncontrolled hypertension. However, clinical presentation and radiological findings are variable and may encompass different cerebral structures. Although pathophysiology is not well established, failure of sympathetic autoregulation in the vertebrobasilar system is thought to be related. This failure leads to breakdown of the blood-brain barrier, hence the vasogenic-type edema appreciated on imaging. Acute obstructive hydrocephalus is a rare and potentially fatal complication of PRES. <h3>Design/Methods:</h3> A 56-year-old Caucasian female who presented due to encephalopathy, headache and falls in the setting of hypertensive emergency. CT (Computed Tomography) head showed hypodense pons, midbrain, cerebellum, and bilateral thalami with effacement of the fourth ventricle, ventriculomegaly in the lateral and 3rd ventricles with associated trans-ependymal edema. Due to initial concern of posterior fossa mass leading to acute hydrocephalus, neurosurgery was consulted, and extra ventricular drain (EVD) was placed for emergent CSF diversion. <h3>Results:</h3> MRI Brain with and without contrast showed no evidence of acute ischemia or enhancing lesions. Severe edema was redemonstrated within the pons, midbrain, bilateral thalami, and cerebellum. Susceptibility weighted imaging showed microhemorrhages confined to the brainstem. The patient’s clinical exam improved after blood pressure management and EVD placement. Repeat head CT showed decreased cerebral edema and improvement of fourth ventricle obstruction. Based on presentation of hypertensive encephalopathy with posterior circulation vasogenic edema that improved with blood pressure management, PRES diagnosis was made. <h3>Conclusions:</h3> Posterior fossa predominant PRES is an uncommon presentation that if overlooked may lead to life threatening complications. Early recognition of clinical manifestations and radiological findings may lead to favorable outcomes. <b>Disclosure:</b> Dr. Morales-Nunez has nothing to disclose. Dr. Baez-Lugo has nothing to disclose. Dr. Yalcin has nothing to disclose. Dr. Shah has nothing to disclose. Dr. Garcia has nothing to disclose. Dr. Nichols has nothing to disclose.

Acute hydrocephalus caused by a colloid cyst — a case report

BackgroundColloid cysts are rare benign, slowly growing intracranial tumors of endodermal origin. Most colloid cysts are found incidentally and are asymptomatic, but rarely, they can lead to sudden death.Case presentationA 73-year-old female patient was admitted to our emergency department with complaints of dizziness, nausea, vomiting, fatigue, walking difficulties, and behavioral changes. CT imaging revealed acute obstructive hydrocephalus attributable to a third ventricular colloid cyst. The patient was immediately transferred to a tertiary center where she underwent successful neurosurgical resection of the mass. Pathology results of the lesion confirmed the diagnosis of colloid cyst.ConclusionThe case we present emphasizes the critical importance of prompt identification of warning signs, complex thinking, and evaluation. Establishing the right diagnostic approach early on can facilitate accurate diagnosis.

A case of successful intraventricular thrombolysis and external ventricular drain treatment in primary intraventricular hemorrhage

Intraventricular hemorrhage (IVH), accounting for about 45% of acute spontaneous intracranial hemorrhage (ICH), is often associated with obstructive hydrocephalus and poor functional outcomes [1] [2]. Obstructive hydrocephalus and increased intracranial pressure are common after IVH because of an obstruction of normal cerebrospinal fluid (CSF) flow and absorption by blood clots. An external ventricular drain (EVD) - a temporary system that permits drainage of cerebral spinal fluid (CSF) from the ventricles to an external closed system) has been indicated for patients with IVH with hydrocephalus and neurologic decline [3]. However, the treatment with EVD alone is often not sufficiently effective due to a likely potential obstruction of the catheter by blood clots. Intraventricular fibrinolysis (IVF) via the extra-ventricular drain has been known to speed clot resolution and maintain the EVD functionality [4]. However, it is also possible that the risk of hemorrhage, infection, and CFS pleocytosis may be increased with IVF therapy, but these have not been demonstrated so far. We report a clinical case of primary IVH with acute obstructive hydrocephalus, successfully treated with a combination of EVD and direct intraventricular injection of rt-PA into the lateral ventricles. This treatment contributes to confirm that combination of EVD and thrombolysis could be considered as a treatment option for selected patients.

Simultaneous biportal endoscopic management of pineal region tumors in patients with obstructive hydrocephalus: technical notes

BackgroundThe goal of this study is to show the feasibility and benefits of using the simultaneous biportal endoscopic procedure to treat pineal tumors in patients with obstructive hydrocephalus.MethodsWe retrospectively reviewed three patients with pineal tumors and acute obstructive hydrocephalus who were treated in one session with a frameless stereotactic guided simultaneous biportal endoscopic third ventriculostomy and endoscopic tumor biopsy performed through two separate ports using one rigid ventriculoscope.ResultsIn the three patients, ventriculostomy and endoscopic biopsies were conducted. There was no death or morbidity throughout the 45-min procedure. All of the patients’ histological findings were confirmed. Germinoma was diagnosed in two patients who recieved postoperative radiotherapy, and the third patient diagnosed with a pineocytoma. Magnetic resonance imaging with flow-sensitive sequences was used to confirm ventriculostomy patency in all patients 6 months after the surgery.ConclusionBiportal endoscopic approach enables better visual control of both procedures. Furthermore, it allows the surgeon to safely pass the ventriculoscope via the foramen of monro, even if it is narrow. Moreover, during endoscopic tumor biopsy and third ventriculostomy, the intracranial pressure can be smoothly managed using the outlet tubes accessible. This treatment may be an alternative to traditional uniportal endoscopic operations in certain patients.

Posterior Fossa Intradural Dermoid Cyst with a Dermal Sinus Complicating with Cerebellar Abscess and Acute Obstructive Hydrocephalus in a Child: Case Report

Posterior Fossa Dermoid Cysts (PFDCs), associated with a Dermal Sinus (DS), are rare congenital brain tumors. More rarely, PFDCs may complicate with cerebellar abscess or hydrocephalus. These complications are represented in only a few case reports as a separate entity.

Acute obstructive hydrocephalus in posterior reversible encephalopathy syndrome

Posterior reversible encephalopathy syndrome (PRES) is an uncommon, subacute neurological disorder that presents radiologically with a pattern of bilateral parieto-occipital areas of vasogenic oedema. Conditions commonly associated with PRES include autoimmune disorders, cytotoxic drugs, metabolic abnormalities and, most frequently, hypertensive emergencies. Clinically, headache, visual disturbances, seizures and an altered level of consciousness are often reported. The outcome is favourable if the underlying cause is addressed. Posterior fossa involvement resulting in obstructive hydrocephalus is a rare presentation and may be misdiagnosed as a mass lesion or infection, leading to delayed or unnecessary treatment. We describe the clinical presentation, findings on neuroimaging and conservative management of a man with PRES resulting in severe cerebellar oedema and acute obstructive hydrocephalus. This case illustrates that awareness of atypical neuroimaging in PRES is important for the management of these patients and to avoid morbidity and mortality.

Clinical Comparison of FD-CT and MS-CT in Aneurysmal Subarachnoid Haemorrhage: A Single Center Experience.

Single-center comparison of postinterventional multislice computed tomography (MS-CT) and flat-detector computed tomography (FD-CT) in patients with subarachnoid haemorrhage (SAH) and endovascularly treated cerebral aneurysms with a focus on detection of posttherapeutical complications. Patients with endovascularly treated aneurysmal SAH undergoing both MS-CT and FD-CT within 24 h after intervention were included. Datasets were compared regarding image quality (IQ) as well as qualitative (detection of SAH, intracerebral haemorrhage [ICH], intraventricular haemorrhage [IVH], external ventricular drain [EVD] position, acute obstructive hydrocephalus [AOH]) and quantitative (cella media distance [CMD], modified Graeb score [GS]) parameters. 410 patients with endovascularly treated aneurysmal SAH were included. IQ was equal between MS-CT and FD-CT. FD-CT allowed equal detection of SAH and ICH in comparison to MS-CT. FD-CT allowed excellent detection of IVH and delineation of EVD position with strong agreement to MS-CT findings. FD-CT allowed equal detection of AOH in comparison to MS-CT. There was no significant difference of CMD and GS between FD-CT and MS-CT. Postinterventional FD-CT yields equivalent diagnostic value in patients with endovascular treated SAH as MS-CT. Enabling reliable detection of SAH-associated complications within the angiosuite, FD-CT might be an efficient and safe imaging modality in these clinical emergencies.

Probable Hydrocephalus Decompensation after Immunization with Pentavalent Vaccine: Case Report and Literature Review

AbstractThere are several complications associated with immunization with the pentavalent vaccine. Most of them are mild reactions, of spontaneous resolution; however, though rare, serious and potentially-fatal adverse effects can occur. We report a case of acute intracranial hypertension syndrome in an infant with a previously-unknown suprasellar arachnoid cyst who developed acute obstructive hydrocephalus after immunization with the pentavalent vaccine. He underwent neuroendoscopic treatment, showing complete resolution of the condition. The present article aims to compare the activation of the immune system by the pertussis component of the vaccine and the mechanisms that hypothetically potentiated the pathological decompensation.

Rare Case of Pediatric Disseminated Choroid Plexus Papilloma: Literature Review and Call for Reclassification

Introduction: Choroid plexus tumors are rare neuroectodermal tumors that arise from the choroid plexus. Choroid plexus papillomas (CPPs) represent the lowest grade of these types of tumors and have a WHO grade I designation. Despite their typical low grade, some CPPs can exhibit aggressive behaviors including parenchymal invasion and dissemination throughout the neuro-axis. Due to their association with the choroid plexus, patients with CPP commonly present with signs and symptoms of hydrocephalus and increased intracranial pressure. Case Presentation: A 2-year-old male presented in extremis with acute hydrocephalus and seizure. He was found to have a large left intraventricular mass with innumerable intraparenchymal and extra-axial cysts throughout his neuro-axis. A literature review revealed five similar disseminated CPP cases with innumerable lesions. This is the youngest reported patient with disseminated CPP and the first with multiple compressive lesions. Following cranial resection and thoracic decompression, the patient’s lesions have remained stable (2 years of follow-up). A literature search of the PubMed/Medline databases was performed using the search terms [“disseminated choroid plexus papilloma” OR “choroid plexus papilloma” OR “metastatic choroid plexus papilloma”] up to March 2021. Articles were then screened for similar patient radiographic presentation and histological diagnosis. To mitigate publication bias, referenced articles were utilized to identify other case reports and case series. Discussion/Conclusion: We describe a rare case of a lateral ventricle CPP with widespread leptomeningeal dissemination causing acute obstructive hydrocephalus and compressive myelopathy requiring cerebrospinal fluid diversion and intracranial resection followed by thoracic spine decompression. This case report serves to broaden knowledge of disseminated CPP and to encourage complete neuro-axis imaging for choroid plexus tumors. Additionally, we propose a naming paradigm refinement that includes radiographic characteristics.

Clinical Features, Diagnosis, and Treatment of Primary Intraventricular Lymphoma: Insights From a Monocentric Case Series.

ObjectivePrimary ventricular lymphoma (PVL) is an extremely rare and commonly misdiagnosed disease. Previous studies were predominantly case reports, and literature regarding the diagnosis and treatment of PVL is limited. Therefore, this study aimed to evaluate the characteristics of patients with PVL.MethodsThe data of patients with pathologically confirmed PVL were assessed. Epidemiological data, imaging findings, surgery, pathological results, and prognosis were retrospectively analyzed. A systematic review of relevant literature was also conducted.ResultsA total of eight patients with PVL were identified. The main symptom was increased intracranial pressure. Radiographically, five patients had single lesion and three had multiple lesions; typical findings on magnetic resonance imaging included hypointensity on T1- and T2-weighted imaging, adjacent brain edema, and homogeneous enhancement on contrast-enhanced T1-weighted images. Preoperatively, six cases were misdiagnosed and two cases did not get a definite diagnosis. Craniotomy was performed on all patients, and four achieved gross total resection. Hydrocephalus was relieved after surgical resection in four patients. Pathology revealed diffuse large B-cell lymphoma in all patients. Only one patient had a severe complication. A total of three patients received concomitant adjuvant treatment, whereas five patients refused any adjuvant therapy. At the time of follow-up, the median survival time of patients was 15 months.ConclusionPrimary ventricular lymphoma mainly presented with symptoms of increased intracranial pressure and had several imaging characteristics for the diagnosis, but the condition still tends to be misdiagnosed. Surgical resection is a feasible treatment for patients with isolated nodules, especially those with acute obstructive hydrocephalus.

Factors Associated with Acute Obstructive Hydrocephalus After Retrosigmoid Approach for Extra-Axial Cerebellopontine Angle Tumors

This study aimed to identify the risk factors for acute obstructive hydrocephalus (AOHCP) after extra-axial cerebellopontine angle (CPA) tumor surgery using the retrosigmoid (RS) approach. This retrospective study assessed 154 patients (100 vestibular schwannomas, 34 CPA meningiomas [MNGs], 9 trigeminal schwannomas, and 11 petroclival MNGs) who underwent surgical resection using the RS approach by a single surgeon between August 2010 and September 2019. AOHCP was defined as postoperative ventricular enlargement due to cerebrospinal fluid flow obstruction caused by surgery-related cerebellar injury within 1week. The radiological characteristics of the tumors were classified, and the surgical outcomes were reviewed. We analyzed the impact of different factors on the development of AOHCP after surgery. AOHCP developed in 17 (11%) patients, all of whom were treated with external ventricular drain insertion. Multivariate analysis showed that CPA MNGs (odds ratio [OR], 37.98), grade of tumor extension beyond the petroclival junction (grade 1: OR, 16.42; grade 2: OR, 17.47), major fourth ventricle compression (OR, 17.77), and surgery-related hemorrhage (OR, 7.64) were associated with AOHCP. Surgery-related hemorrhage was observed in 17 (11%) patients. 9 (6%) patients underwent ventriculoperitoneal shunt surgery because of persistent HCP. An increased risk of AOHCP after the RS approach was observed in patients with extra-axial CPA tumors with clival extension and major fourth ventricle compression. Compulsive and meticulous hemostasis must be achieved because postoperative hemorrhage is associated with AOHCP.

Giant Posterior Inferior Cerebellar Artery Aneurysm Mimicking a Brainstem Tumor

Aneurysms from the vertebrobasilar system are rare, accounting for only 5%-10% of all intracranial aneurysms. The most common sites in which these lesions occur are the bifurcation of the basilar artery and the origin of the posterior inferior cerebellar artery (PICA). When the aneurysms present in the distal portion of the PICA, they represent from 0.5% to 6%. These aneurysms are called giant when they exceed 25 mm in diameter. We present a case of a 49-year-old male who presented with acute obstructive hydrocephalus, which required ventriculoperitoneal shunting and left hemispheric cerebellar syndrome. The magnetic resonance imaging study revealed an occupative mass located in the fourth ventricle, and diagnostic angiography showed a partially thrombosed giant saccular aneurysm in the posterior inferior cerebellar artery. He underwent surgical management via a lateral suboccipital approach. The aneurysm was remodeled and clipped successfully without complications, with an uneventful postoperative course.Although rare, PICA aneurysms should always be considered when posterior fossa syndrome occurs, including brainstem and cranial nerve compression symptoms. It can easily be misdiagnosed as a neoplastic lesion, especially when the aneurysm reaches big or giant size. Therefore, complete diagnostic studies, such as cerebral angiography, must be performed. Surgical clipping must be offered as the first line of treatment. It provides occlusion of the aneurysm and relieves compressive symptoms.

De novo brain AVM following radiotherapy for cerebral cavernous malformation in a child: A 15-year clinical course.

Multiple de novo brain arteriovenous malformations (bAVM) have been reported in the literature, raising questions about the contended purely congenital nature of these lesions. We present the 15-year course of a pediatric patient, who initially presented at age 5 with a thalamic cavernous malformation and was treated with radiosurgery, and then subsequently developed a thalamic de novo bAVM immediately adjacent to the initial lesion location, discovered 2years later. Treatment of the bAVM entailed two transarterial embolizations and one radiosurgery session which ultimately led to complete angiographic resolution. Finally, this patient's course was complicated by intraparenchymal hemorrhage and acute obstructive hydrocephalus, and further imaging revealed two newly formed cavernous malformations, also associated with the initial lesion's location, that have remained stable since their formation. This case likely represents the second-hit model for the formation of vascular malformations, as sparsely supported by the current literature. According to this, genetically aberrant, yet quiescent, brain areas might promote the de novo formation of vascular malformations after brain injury, including radiation.