Subtemporal-Transtentorial Approach for Microsurgical Resection of Hemorrhagic Ambient Cistern Arteriovenous Malformation.

Arteriovenous malformations (AVMs) of the ambient cistern are an extremely rare and complex subgroup of vascular malformation, representing a clinical challenge due to the deep-seated, highly eloquent anatomic location and the debilitating, life-threatening consequences related to hemorrhagic presentation and surgical morbidity. Ultimately, a tailored treatment, based on the presenting symptoms, AVM angioarchitecture, and annual risk of hemorrhage should be discussed among a multidisciplinary team to find the best individualized strategy balancing between the pros and cons of each approach. In Video 1, we present the case of a 60-year-old man with a hemorrhaged AVM of the right ambient cistern, present the pros and cons of each possible treatment strategy, and illustrate the successful resection of this lesion through a subtemporal-transtentorial microsurgical approach.

Enhanced Meningeal Lymphatic Drainage Ameliorates Neuroinflammation and Hepatic Encephalopathy in Cirrhotic Rats.

BACKGROUND & AIMS: Hepatic encephalopathy (HE) is a serious neurologic complication in patients with liver cirrhosis. Very little is known about the role of the meningeal lymphatic system in HE. We tested our hypothesis that enhancement of meningeal lymphatic drainage could decrease neuroinflammation and ameliorate HE. METHODS: A 4-week bile duct ligation model was used to develop cirrhosis with HE in rats. Brain inflammation in patients with HE was evaluated by using archived GSE41919. The motor function of rats was assessed by the rotarod test. Adeno-associated virus 8-vascular endothelial growth factor C (AAV8-VEGF-C) was injected into the cisterna magna of HE rats 1 day after surgery to induce meningeal lymphangiogenesis. RESULTS: Cirrhotic rats with HE showed significantly increased microglia activation in the middle region of the cortex (P < .001) as well as increased neuroinflammation, as indicated by significant increases in interleukin 1ß, interferon γ, tumor necrosis factor α, and ionized calcium binding adaptor molecule 1 (Iba1) expression levels in at least 1 of the 3 regions of the cortex. Motor function was also impaired in rats with HE (P < .05). Human brains of patients with cirrhosis with HE also exhibited up-regulation of proinflammatory genes (NFKB1, IbA1, TNF-α, and IL1ß) (n = 6). AAV8-VEGF-C injection significantly increased meningeal lymphangiogenesis (P = .035) and tracer dye uptake in the anterior and middle regions of the cortex (P = .006 and .003, respectively), their corresponding meninges (P = .086 and .006, respectively), and the draining lymph nodes (P = .02). Furthermore, AAV8-VEGF-C decreased microglia activation (P < .001) and neuroinflammation and ameliorated motor dysfunction (P = .024). CONCLUSIONS: Promoting meningeal lymphatic drainage and enhancing waste clearance improves HE. Manipulation of meningeal lymphangiogenesis could be a new therapeutic strategy for the treatment of HE.

An Uncommon Case of Neuroenteric Cyst Located at the Lateral Cerebellomedullary Cistern.

We present the case of a 42-year-old woman with a 5-week history of headache, progressive dysphagia, dysphonia, and hoarseness. A brain magnetic resonance imaging revealed an extra-axial cyst of the left lateral cerebellomedullary cistern. The subsequent histopathologic examination diagnosed a neuroenteric cyst. This case sheds light on the pivotal role of histologic identification of neuroenteric cyst, which could be crucial for further diagnostic investigations, especially in pediatric patients.

The Clinical and Molecular Characteristics of Molybdenum Cofactor Deficiency Due to MOCS2 Mutations.

BACKGROUND: We explored the clinical and molecular characteristics of molybdenum cofactor deficiency due to MOCS2 muations. METHODS: We summarize the genetic and clinical findings of previously reported patients with a MOCS2 mutation. We also present a new patient with novel neuroradiological findings associated with molybdenum cofactor deficiency due to a novel homozygous variant in the 5' untranslated region of the MOCS2 gene. RESULTS: The study population comprised 35 patients with a MOCS2 gene mutation. All reported children had delayed motor milestones. The major initial symptom was seizures in neonatal period. Facial dysmorphism was present in 61% of the patients. Only one patient had ectopia lentis. Agenesis of the corpus callosum and an associated interhemispheric cyst in our case are novel neuroradiological findings. CONCLUSIONS: The occurrence of neonatal seizures and feeding difficulties can be the first clinical signs of molybdenum cofactor deficiency. Although there is no effective therapy for this condition, early diagnosis and genetic analysis of these lethal disorders facilitate adequate genetic counseling.

Non-dysraphic intramedullary lipoma of the craniocervical region in an adult: Case report.

Intradural spinal lipomas with intracranial extension are very rare and are typically diagnosed in childhood. Radical surgical excision usually causes a high rate of morbidity because of the firm adherence between the lipoma and neural tissues. In this report, we present a case of craniocervical intradural intramedullary lipoma in an adult patient. The patient underwent surgery with excision of the mass, leaving a sheet of lipoma on the tumor bed.

Cisterna magna meningiomas without dural attachment: Report of two cases.

Meningiomas within the cisterna magna without dural attachment are extremely rare. To the best of our knowledge, only three cases of meningiomas within the cisterna magna have been reported in the literature. The authors present two cases of patient with the cisterna magna meningioma without dural attachment. (Case 1) A 36-year-old female presented with a 10-month history of numbness in the left hand. Magnetic resonance imaging (MRI) disclosed the presence of a contrast-enhanced tumor in the posterior fossa. A suboccipital craniectomy was performed, and the tumor located within the cisterna magna with no attachment to the dura. Diagnosis is made as clear cell meningioma. The postoperative course was uneventful, and a recurrence has not been observed for three years. (Case 2) A 58-year-old man presented with a well-circumscribed mass in the posterior fossa. At surgery, the tumor located within the cisterna magna with a connection to the right tenia. The tumor was totally removed without neurological deficits. At a 7-year follow-up, no evidence of a recurrence was observed. It is quite difficult to preoperatively diagnose as a cisterna magna meningioma without dural attachment. However, complete removal of the tumor should be achieved.

Clinical features and neuroimaging (CT and MRI) findings in presumed Zika virus related congenital infection and microcephaly: retrospective case series study.

OBJECTIVE: To report radiological findings observed in computed tomography (CT) and magnetic resonance imaging (MRI) scans of the first cases of congenital infection and microcephaly presumably associated with the Zika virus in the current Brazilian epidemic. DESIGN: Retrospective study with a case series. SETTING: Association for Assistance of Disabled Children (AACD), Pernambuco state, Brazil. PARTICIPANTS: 23 children with a diagnosis of congenital infection presumably associated with the Zika virus during the Brazilian microcephaly epidemic. MAIN OUTCOME MEASURES: Types of abnormalities and the radiological pattern of lesions identified on CT and MRI brain scans. RESULTS: Six of the 23 children tested positive for IgM antibodies to Zika virus in cerebrospinal fluid. The other 17 children met the protocol criteria for congenital infection presumably associated with the Zika virus, even without being tested for IgM antibodies to the virus--the test was not yet available on a routine basis. Of the 23 children, 15 underwent CT, seven underwent both CT and MRI, and one underwent MRI. Of the 22 children who underwent CT, all had calcifications in the junction between cortical and subcortical white matter, 21 (95%) had malformations of cortical development, 20 (91%) had a decreased brain volume, 19 (86%) had ventriculomegaly, and 11 (50%) had hypoplasia of the cerebellum or brainstem. Of the eight children who underwent MRI, all had calcifications in the junction between cortical and subcortical white matter, malformations of cortical development occurring predominantly in the frontal lobes, and ventriculomegaly. Seven of the eight (88%) children had enlarged cisterna magna, seven (88%) delayed myelination, and six each (75%) a moderate to severe decrease in brain volume, simplified gyral pattern, and abnormalities of the corpus callosum (38% hypogenesis and 38% hypoplasia). Malformations were symmetrical in 75% of the cases. CONCLUSION: Severe cerebral damage was found on imaging in most of the children in this case series with congenital infection presumably associated with the Zika virus. The features most commonly found were brain calcifications in the junction between cortical and subcortical white matter associated with malformations of cortical development, often with a simplified gyral pattern and predominance of pachygyria or polymicrogyria in the frontal lobes. Additional findings were enlarged cisterna magna, abnormalities of corpus callosum (hypoplasia or hypogenesis), ventriculomegaly, delayed myelination, and hypoplasia of the cerebellum and the brainstem.

Widespread and efficient transduction of spinal cord and brain following neonatal AAV injection and potential disease modifying effect in ALS mice.

The architecture of the spinal cord makes efficient delivery of recombinant adeno-associated virus (rAAV) vectors throughout the neuraxis challenging. We describe a paradigm in which small amounts of virus delivered intraspinally to newborn mice result in robust rAAV-mediated transgene expression in the spinal cord. We compared the efficacy of rAAV2/1, 2/5, 2/8, and 2/9 encoding EGFP delivered to the hindlimb muscle (IM), cisterna magna (ICM), or lumbar spinal cord (IS) of neonatal pups. IS injection of all four capsids resulted in robust transduction of the spinal cord with rAAV2/5, 2/8, and 2/9 vectors appearing to be transported to brain. ICM injection resulted in widespread expression of EGFP in the brain, and upper spinal cord. IM injection resulted in robust muscle expression, with only rAAV2/8 and 2/9 transducing spinal motor and sensory neurons. As proof of concept, we use the IS paradigm to express murine Interleukin (IL)-10 in the spinal cord of the SOD1-G93A transgenic mouse model of amyotrophic lateral sclerosis. We show that expression of IL-10 in the spinal axis of SOD1-G93A mice altered the immune milieu and significantly prolonged survival. These data establish an efficient paradigm for somatic transgene delivery of therapeutic biologics to the spinal cord of mice.

[A case of filamentous fungal infection showing tumor-like expansion in the cisterns].

A 67-year-old woman was admitted for headache. The initial MRI showed a gadolinium-enhanced lesion in the prepontine area. Initial and repeated CSF examinations were negative for the fungal infection. Since the enhanced lesion expanded in the cisterns, and showed tumor-like appearance, brain biopsy was performed at 3 months from her first admission. Histological studies revealed filamentous fungal infection probably caused by the pseudallescheria boydii. Intrathecal miconazole injection through the Ommaya reservoir successfully ameliorated patient's symptoms and the MRI findings. Primary cisternal fungal infection showing tumor-like expansion typically fails to demonstrate its supportive findings by the CSF examination. Therefore, histopathological assessment after brain biopsy should be considered in cases that are not conclusive by means of conventional laboratory examinations.

Psychiatric manifestations associated with mega cisterna magna.

The Dandy-Walker variant is a milder form of the Dandy-Walker complex and is characterized by normal-sized posterior fossa, mild vermian hypoplasia, and a cystic lesion that communicates with the fourth ventricle. This syndrome has been described in association with schizophrenia, obsessive-compulsive disorder, manic episode, psychosis (delusional type), and recurrent catatonia. The authors present two cases of mega cisterna magna associated with mania and catatonic schizophrenia.

Surgical treatment of Chiari I malformation with ventricular dilation.

Ventricular dilation affects 7% to 10% of patients with Chiari type I malformation (CIM), but the choice of surgical treatment is controversial. To study the surgical approaches for treating CIM with ventricular dilation and to evaluate the efficacy of posterior fossa decompression (PFD), clinical and imaging data of 38 adult patients who received surgical correction performed at the authors' department from 2004 to 2011 were reviewed. Ventricular dilation was defined as Evans' index > 0.30. Preoperative fundus examinations were done on all patients and no papilledema was found. Surgical procedures included a sub-occipital decompression and a C1 laminectomy, followed by a duraplasty with an autologous graft. Evans' index was measured before and after surgery respectively, and a paired samples t-test was performed to examine the difference. Factors predicting outcomes were investigated using logistic regression analysis. Follow-up was done to all patients with an average duration of 43 months. All postoperative magnetic resonance (MR) images showed a relief of cervicomedullary compression and recreation of the cisterna magna. Symptoms improved in 33 patients (86.8%), remained stable in 5 (13.2%), and no patient deteriorated. No significant change in ventricular size was observed after surgery (P = 0.257). Regression analysis showed duration of illness had a significant effect on clinical outcome (P = 0.034, OR = 12.5, 95% CI: 1.214, 128.661). Our study suggests that the intracranial pressure (ICP) of patients with CIM and ventricular dilation is usually normal. PFD with duraplasty is an effective and safe treatment for CIM with ventricular dilation. Treatment of ventricular dilation is unnecessary before PFD as long as there is no persistent headache, vomiting, and papilledema.

Intracisternal interleukin-1 receptor antagonist prevents postoperative cognitive decline and neuroinflammatory response in aged rats.

To investigate the role of the pro-inflammatory cytokine interleukin-1ß (IL-1ß) in postoperative cognitive dysfunction (POCD) in aged rats, we used laparotomy to mimic human abdominal surgery in adult (3 months) and aged (24 months) F344/BN rats. We demonstrated that memory consolidation of the hippocampal-dependent contextual fear-conditioning task is significantly impaired in aged but not young rats 4 d after surgery. Hippocampal-independent auditory-cued fear memory was not disrupted by laparotomy in either age group. The hippocampal-dependent memory impairment was paralleled by elevations of IL-1ß in the hippocampus of aged animals 1 and 4 d after surgery. These findings support our substantial line of previous research showing that aged animals are more vulnerable to cognitive decline after a peripheral immune challenge. In addition, we demonstrated that a single intracisternal administration of interleukin-1 receptor antagonist (IL-1RA; 112 µg) at the time of surgery was sufficient to block both the behavioral deficit and the neuroinflammatory response. Injecting the same dose of IL-1RA peripherally failed to have a protective effect. These data provide strong support for the specific role of central, not peripheral, IL-1ß in POCD. Furthermore, the long-lasting presence of IL-1RA in the brain (4 d) compared with in the blood (<24 h) underscores the value of intracisternal administration of IL-1RA for therapeutic purposes.

[Epidermoid cyst of the cisterna magna and the fourth ventricle: Report of four cases]. / Kystes épidermoïdes de la grande citerne et du quatrième ventricule : à propos de quatre cas.

INTRODUCTION: Epidermoid cyst is a congenital and benign tumor, developed from ectodermal inclusion. These cysts occur very rarely in the cisterna magna and the fourth ventricle. OBJECTIVE: To report four cases of epidermoid cyst of the cisterna magna and the fourth ventricle in the light of the data of literature. PATIENTS AND METHODS: We report a retrospective study of four cases of epidermoid cysts of the cisterna magna and the fourth ventricle. The data was collected from January 2000 to December 2006 from to series of 18 cases of epidermoid cysts of posterior cranial fossa (14 cases were localised at the cerebellopontine angle). All the patients had a physical examination and a complete neuroradiological imagery. The treatment was surgical. The follow-up was at least 9 months. RESULTS: There were two men and two women. The mean age was 47.75 years. All patients presented with cerebellar syndrome. Three patients had intracranial hypertension. Neuroradiological explorations showed a cystic lesion developed in the cisterna magna in two cases, in the fourth ventricle in one case and in the two locations in one case. Two patients had hydrocephalus. All patients had surgery with a posterior approach and one patient had first ventriculoperitoneal shunt. The diagnosis was confirmed by histological examination. Postoperatory outcome was favourable in all cases. One patient developed bilateral chronic subdural hematoma, which was surgically removed. A long time follow-up was good in all cases. CONCLUSION: Epidermoid cysts are characterized by a long evolution. The diagnosis is relatively characteristic in the imagery. The prognosis was favourable with a complete surgical resection.

Initial experience with combined endoscopic third ventriculostomy and choroid plexus cauterization for post-hemorrhagic hydrocephalus of prematurity: the importance of prepontine cistern status and the predictive value of FIESTA MRI imaging.

PURPOSE: Post-hemorrhagic hydrocephalus of prematurity (PHHP) is among the most common causes of infant hydrocephalus in developed nations. This population has a high incidence of shunt failure, infection, and slit ventricle syndrome. Although effective for other etiologies of infant hydrocephalus, the efficacy of combined endoscopic third ventriculostomy and choroid plexus cauterization (ETV/CPC) in PHHP has not been investigated. This pilot study reports the initial experience. METHODS: Ten patients (four grade III and six grade IV intraventricular hemorrhage) requiring definitive treatment for PHHP underwent ETV/CPC within 6 months of birth. Seven had a prior ventriculo-subgaleal shunt. Mean age at birth was -12.8 weeks, or 25.2 weeks gestation (24-28 weeks), and at surgery was -1.6 weeks (-11 to +11 weeks). Mean weight at surgery was 3.3 (1.0-5.5 kg). Each patient had preoperative magnetic resonance imaging (MRI) with fast imaging employing steady-state acquisition (FIESTA). RESULTS: Four of ten (40%) required no further operations related to hydrocephalus (mean follow-up, 29.7 months). Six required another procedure (five ultimately shunted). Prepontine cistern status correlated with outcome (p = 0.033). Procedures in all infants with unobstructed cisterns were successful but failed in six of seven with cisternal obstruction, with the one success having an alternative lamina terminalis endoscopic third ventriculostomy. Preoperative MRI FIESTA images correlated well with intraoperative assessment of the cistern. CONCLUSIONS: Results from this small homogenous cohort suggest cistern status is an important determinant of outcome. FIESTA imaging correlated with endoscopic observation. Preliminary analysis suggests ETV/CPC as an effective treatment for PHHP, but only when the cistern is unscarred. This information should guide patient selection for future study protocols.

Intraoperative assessment of cerebral aqueduct patency and cisternal scarring: impact on success of endoscopic third ventriculostomy in 403 African children.

OBJECT: In the setting of a developing country where preoperative imaging may be limited, the authors wished to determine whether cisternal scarring or aqueduct patency at the time of surgery was sufficiently predictive of the failure of endoscopic third ventriculostomy (ETV) to justify shunt placement at the time of the initial operation. METHODS: The status of the prepontine cistern and aqueduct at the time of ventriculoscopy was prospectively recorded in 403 children in whom an ETV had been completed. Kaplan-Meier methods were used to construct survival curves. A Cox proportional hazards model was used to provide estimates of HRs for the time to ETV failure. Several independent variables were tested in a single multivariable model, including those previously shown to be associated with ETV survival, that is, age, hydrocephalus etiology, and extent of choroid plexus cauterization (CPC). In addition, intraoperative variables of particular interest were included in the analysis: status of the aqueduct at surgery (closed vs open) and status of the prepontine cistern at surgery (scarred vs clean/unscarred). Multicollinearity was not a concern since the variance inflation factors for all variables were < 2. The examination of stratified survival curves confirmed the appropriateness of the proportional hazards assumption for each variable. RESULTS: Overall actuarial 3-year success was 57%. Consistent with previous results, age, hydrocephalus etiology, and extent of CPC were significantly associated with ETV success. A closed aqueduct and an unscarred cistern were each independently associated with significantly better ETV success (HRs of 0.66 and 0.44, respectively). The presence of cisternal scarring more than doubled the risk of ETV failure, and an open aqueduct increased the risk of failure by 50%. CONCLUSIONS: Intraoperative observations of the aqueduct and prepontine cistern are independent predictors of the risk of ETV failure and can be used to further refine outcome predictions based on age, hydrocephalus etiology, and extent of CPC. Further studies will test validity in several African centers and determine what threshold of failure risk should prompt shunt placement at the initial operation.

Dermoid tumor with diastematobulbia.

BACKGROUND: Dermoid tumors are rare congenital lesions and account for 0.2% to 1.8% of all intracranial tumors. Dermoid tumor with diastematobulbia is very rare. CASE DESCRIPTION: We report a dermoid tumor in an adult female with an unusual location and morphology. The lesion had 2 major components with different material within the cysts. The posterior part of the dermoid had presented on the floor of the fourth ventricle and had split the pons into 2 distinct halves. The anterior part of the lesion was situated in the prepontine cistern and encircling the anterior half of the brainstem. The lesion was radically excised, and the postoperative images showed return of the 2 halves of the pons to appose each other in the midline. CONCLUSION: This case report demonstrates the anatomical peculiarities of this extremely unusual presentation of a dermoid cyst with diastematobulbia. Total excision of the lesion through a dorsal approach resulted in a good outcome.