Quiste epidermoide intraventricular. Presentación de un caso / Intraventricular epidermoid cyst. A case report

RESUMEN Fundamento: El tumor epidermoide es una lesión benigna que representa cerca del 1 % de las neoplasias intracraneales, su origen es embrionario y son frecuentes en la línea media. Objetivo: Presentar un caso poco frecuente de un quiste epidermoide dentro del cuarto ventrículo, que debutó con hidrocefalia en un paciente de la quinta década de la vida. Presentación clínica: Paciente blanco, masculino, de 49 años que debutó con cefalea, vértigos e inestabilidad para la marcha. Al examen físico neurológico se encontraba consciente, con manifestaciones de un síndrome cerebeloso vermiano. Los estudios de tomografía axial computarizada y de resonancia magnética nuclear simple y contrastada demostraron una lesión homogénea, redondeada con poca captación de contraste, dentro del cuarto ventrículo acompañada de una hidrocefalia triventricular. La estrategia quirúrgica se orientó primero a colocar una derivación ventrículo peritoneal y en un segundo momento se realizó el tratamiento quirúrgico directo a la lesión a través de una craniectomía medial de fosa posterior. Después de la durotomía se observó la lesión nacarada, de aproximadamente 2 cm de diámetro, encapsulada que permitió su resección completa y el restablecimiento de la circulación del líquido cefalorraquídeo. El paciente evolucionó favorablemente con recuperación total de sus manifestaciones clínicas y sin secuelas. Conclusiones: Los quistes epidermoides, aunque predominan en la línea media son muy raros dentro del sistema ventricular. La resonancia magnética es el estudio de elección, el diagnóstico positivo es histopatológico y la resección quirúrgica completa permitieron la curación del enfermo.

ABSTRACT Background: Epidermoid cyst is a benign lesion that represents about 1 % of intracranial neoplasms, of embryonal origin and frequent in the media line. Objective: To present a rare case of an epidermoid cyst within the fourth ventricle in a patient who had hydrocephalus in the fifth decade of life. Clinical report: 49 years old, white male patient, who presented headache, dizziness and gait instability. He was conscious when neurologic physical examination, with appearances of a cerebellar vermis syndrome. Computed axial tomography also simple and contrasted nuclear magnetic resonance imaging studies showed a homogeneous, rounded lesion with low contrast acquisition, within the fourth ventricle, accompanied by triventricular hydrocephalus. The surgical strategy was first oriented to place a ventricle-peritoneal shunt, then direct surgical treatment of the lesion through a posterior fossa medial craniotomy. After dural surgery, a pearly lesion was observed, approximately 2 cm diameter, encapsulated, which allowed its complete resection and the reestablishment of cerebrospinal fluid circulation. The patient evolved positively with total recovery of his clinical manifestations and without any sequela. Conclusions: Epidermoid cysts, although predominant in the media line are very rare within the ventricular system. Magnetic resonance imaging is the choice study, the positive histopathological diagnosis and complete surgical resection allowed the patient to be cured.

Tortícolis como forma de presentación de quiste de la bolsa de Blake. Diagnóstico ecográfico en atención primaria / Torticolis as a form of presentation of Blake's pouch cyst. Ultrasound diagnosis in primary care

La tortícolis es un signo clínico definido por la inclinación lateral del cuello y rotación de la cabeza, que puede ser fija o flexible y acompañarse o no de dolor cervical. Aparece en trastornos de diferente complejidad. Ante un caso de tortícolis, es preciso realizar una historia clínica cuidadosa y un examen físico completo, y, en caso de ser persistente, solicitar pruebas de imagen.Se hace referencia a una causa de tortícolis no descrita en la literatura. Se trata de una tumoración quística compresiva en la fosa craneal posterior, quiste de la bolsa de Blake, en una lactante pequeña diagnosticada mediante ecografía en la consulta de Pediatría de Atención Primaria. Tras el diagnóstico, se remitió al centro hospitalario de referencia, donde se intervino de urgencia por Neurocirugía Pediátrica, mediante fenestración de la tumoración por ventriculostomía endoscópica y derivación ventrículo-peritoneal. Actualmente, se encuentra asintomática y sin secuelas.

Torticollis is a clinical sign defined by the lateral inclination of the neck and rotation of the head, which can be fixed or flexible and accompanied or not by cervical pain. It appears in disorders of different complexity. In a case of torticollis it is necessary to carry out a careful medical history and a complete physical examination and, if persistent, request imaging tests.Reference is made to a cause of torticollis not described in the literature. This is a compressive cystic tumor in the posterior cranial fossa, Blake's pouch cyst, in a small infant diagnosed by ultrasound in the Primary Care Pediatrics office. After diagnosis, she was referred to the referral hospital, where emergency intervention was performed by pediatric neurosurgery, by fenestration of the tumor by endoscopic ventriculostomy and ventriculo-peritoneal shunt. She is currently asymptomatic and without sequelae.

Ventricular-Peritoneal Shunt in Newborns in a High-Risk Maternity Unit: Case Series

Objective To identify factors related to ventricular-peritoneal shunt (VPS) complications in pediatric patients at a high-risk maternity hospital. Methods Prospective study, conducted between September/2018 and June/2019, with selected newborns without previous ventricular bypass who underwent neurosurgery for VPS placement in a high-risk maternity hospital in the state of Sergipe, Brazil. Diagnosis of hydrocephalus occurred by transfontanelle ultrasound. The variables were analyzed by Student t-test, adopting p < 0.05 as statistical significance. Results Seven newborns participated in the study, 3 male and 4 female. Folic acid supplementation during pregnancy was considered a positive influencing factor in the 1st minute Apgar.Hydrocephalus secondary to premature hemorrhagewas present inmost newborns. Prematurity, 1st minute Apgar score < 7, and birth weight< 2,500 g did not represent a significant negative risk factor for prolonged hospitalization after neurosurgery. One newborn had cerebrospinal fluid infection and was the only one with heart disease. Conclusion This is the first scientific research that associates the benefits of maternal use of folic acid during pregnancy to better newborn Apgar scores. Only one newborn developed complications after neurosurgery, the only one with an associated comorbidity. Further studies are needed to provide more evidence on risk factors related to complications of VPS implantation in newborns. This neurosurgical procedure in a highrisk maternity contributed to the early management of hydrocephalus.

Bruns Syndrome Caused by Intraventricular Neurocysticercosis: Literature Review

Bruns syndrome is one of the clinical presentations of intraventricular neurocysticercosis, and it is characterized by episodes of headache, vertigo and vomiting. The intraventricular form of neurocysticercosis occurs in 7% to 20% of the cases, and it is more serious than the intraparenchymal form. The management is primarily surgical, associated with pharmacological therapy with anthelmintic drugs and corticosteroids. We report the case of a patient who presented Bruns syndrome due to neurocysticercosis.

Epidermoid Cyst of the IV Ventricle: Case Report

Epidermoid cysts constitute congenital, benign and rare lesions, corresponding to 0.2% to 1.8% of all intracranial tumors. Only 5% of the cases are located in the fourth ventricle. Despite their genesis in intrauterine life, they are usually diagnosed between the third and fifth decades of life due to their very slow growth pattern. The image weighted by the diffusion of the magnetic resonance is essential to establish the diagnosis. The ideal treatment consists of emptying the cystic content with complete capsule resection. In the present work, we report the case of a 31-year-old female with cerebellar syndrome that evolved with intracranial hypertension. The symptomatology was due to an obstructive hydrocephalus by an epidermoid cyst located inside the fourth ventricle, which was confirmed by the pathological anatomy.

Medical therapy using omeprazole in 12 hydrocephalic dogs: clinical, diagnostic, and therapeutic findings / Terapia médica utilizando omeprazol em 12 cães hidrocefálicos: achados clínicos, diagnósticos e terapêuticos

According to experimental studies with healthy dogs, omeprazole might decrease the CSF production by about 26%; therefore, book texts have been suggested the usage of omeprazole in medical protocols for hydrocephalus treatment. However, to the best knowledge of the authors, the usage and medical response of the omeprazole with substantial group of illness dogs, such as hydrocephalic animals, was lacking. This report describes clinical, diagnostic, and therapeutic findings in 12 dogs with hydrocephalus in which omeprazole were used for medical treatment. The diagnosis of hydrocephalus was accomplished by transcranial sonography (TCS) and/or computed tomography. The ventricular measurement was assessed periodically by TCS during medical treatment. Six dogs were diagnosed with non-obstrutive hydrocephalus and in the other 6 cases hydrocephalus occurred with other concomitant anomalous encephalic disease often related with obstructive hysdrocephalus, such as quadrigeminal cist, arachnoid cyst, chiary-like malformation, and syringomyelia. All of them had medical improvement after the use of omeprazole and the most of the cases had ventricular size reduction. In 10 dogs, the omeprazole was used as single drug, and in 2 dogs medical treatment with steroids and/or diuretics was previously being performed, and omeprazole was added because conventional treatment was resulting in mild to unsatisfactory medical control of the neurological status. The results of this paper shown that omeprazole may be used to ameliorate the neurological status in symptomatic hydrocephalic dogs. This work may represent the first description about the use of omeprazole in order to treat a substantial group of affected dogs with suspected increased intracranial pressure by hydrocephalus, probably due to limitation of CSF production.(AU)

O omeprazol diminui a produção do fluido cerebrospinal (FCE) por cerca de 26% de acordo com estudos experimentais em cães saudáveis. Segundo o conhecimento dos autores, embora utilizado na prática clínica e recomendado em livros textos, não há até o momento estudos clínicos em um grupo substancial de animais avaliando a resposta terapêutica ao uso do omeprazol em pacientes enfermos, tais como cães hidrocefálicos sintomáticos. Este trabalho descreve os achados clínicos, diagnósticos e terapêuticos em 12 cães com hidrocefalia que foram submetidos ao tratamento com omeprazol para o manejo médico de hidrocefalia. O diagnóstico de hidrocefalia e doenças neurológicas concomitantes foi realizado por ultrassonografia transcraniana (USTC) e/ou tomografia computadorizada. A mensuração do tamanho ventricular foi realizada pela USTC durante o tratamento médico. Seis cães foram diagnosticados com hidrocefalia não obstrutiva e os outros 6 casos apresentaram hidrofalia concomitante com outras afecções encefálicas anômalas comumente associada à hidrocefalia obstrutiva, tal como cisto quadrigêmio, cisto aracnóide, síndrome de chiari-like e seringomegalia. Em 10 cães o omeprazol foi utilizado como droga única e em 2 cães a terapia inicial foi a convencional utilizando esteroides e diuréticos, e o omeprazol foi adicionado, pois a resposta clínica a terapia convencional foi insatisfatória. Todos os animais obtiveram melhora dos parâmetros neurológicos e a maioria teve uma redução do tamanho ventricular após o uso do omeprazol. Os resultados deste estudo demonstram que o omeprazol pode ser utilizado para melhorar o estado neurológico em cães com hidrocefalia. Este estudo representa a primeira descrição clínica usando o omeprazol para tratar uma série de cães com suspeita de aumento da pressão intracraniana devido à hidrocefalia, provavelmente pela capacidade do fármaco em limitar a produção do FCE.(AU)

Migration of Oxidized Cellulose to the Ventricle as a Complication of Endoscopic Third Ventriculostomy: A Case Report

Endoscopic third ventriculostomy (ETV) is an increasingly common neurosurgical procedure. Hemostatic agentes (porcine gelatin and oxidized cellulose) are normally placed to plug the cortical hole after ETV to avoid cerebral spinal fluid leakage, subdural hygroma, and hemorrhage. Here we report the case of a 6-year-old boy with hydrocephalus who underwent ETV and which oxidized cellulose was placed to plug the cortical hole.Magnetic resonance imaging of the head performed 3 months after the procedure showed the presence of oxidized cellulose in the ventricle. After an unsuccessful attempt to remove the cellulose, it was decided that the patient should be kept under observation. Twoyears later, the child is in good health and without any complaints. Hemostatic agents (especially oxidized cellulose) used on the cortical hole after ETV can migrate to the ventricle and compromise the procedure. Follow-up should be performedfor such patients, and the main focus should be on not causing further injury.

Perfil clínico e epidemiológico de crianças internadas por hidrocefalia num hospital municipal de São Paulo no período de 2014 a 2016 / Clinical and epidemiological profile of children hospitalized by hydrocephalia in a municipal hospital of São Paulo in the period 2014 to 2016

Fundamento: A hidrocefalia é acúmulo anormal de líquido cefalorraquidiano (LCR) nos ventrículos, ocasionando anormalidades funcionais e neuropsíquicas, gerando impacto para crianças, familiares e profissionais da saúde. Objetivos: Descrever a prevalência do sexo, idade, achados clínicos, idade de diagnóstico e as possíveis associações da hidrocefalia. Métodos: Trata-se de um estudo retrospectivo, a partir da análise dos prontuários de crianças de 0 a 3 anos com diagnóstico de hidrocefalia, internados na enfermaria de pediatria do Hospital Municipal Doutor Alípio Correa Netto (São Paulo - SP), no período de janeiro de 2014 a dezembro de 2016. Os dados coletados foram apresentados em relação a à porcentagem dos achados e para a análise estatística foi utilizado o cálculo de razão de chances e o intervalo de confiança pelo programa EZ-R Excel 1.99. Resultados: Foram avaliados 34 prontuários, sendo 50% de cada gênero, 50% prematuras com perímetro cefálico normal (26.5%), idade de diagnóstico menor que 6 meses (73.5%), convulsão (37.2%) como principal sintoma. O diagnóstico foi realizado por TC (61.7%). Foi encontrado que a idade materna entre 15 e 20 anos, assim como o peso ao nascimento menor 2500g estão associados aos casos de hidrocefalia. O diagnóstico da hidrocefalia, nas crianças acompanhadas no referido hospital, foi realizado principalmente por TC crânio, predominantemente em menores de 6 meses, e a convulsão foi o sintoma prevalente, podendo ser usado como alerta.(AU)

Background: Hydrocephalus is an abnormal accumulation of cerebrospinal fluid (CSF) in the ventricles, causing functional and neuropsychic abnormalities, generating impact for children, family members and health professionals. Objectives: To describe the prevalence of gender, age, clinical findings, age of diagnosis and possible associations of hydrocephalus. Methods: This is a retrospective study, based on the analysis of the children aged 0 to 3 years with diagnosis of hydrocephalus, hospitalized in the pediatrics at the Municipal Hospital Doctor Alípio Correa Netto (São Paulo - SP), from January 2014 to December 2016. The data collected were presented in relation to the percentage of the findings and for the statistical analysis, the Odds ratio and the confidence interval by the program EZ-R Excel 1.99. Results: 34 medical records were analyzed, 50% of each genus, 50% premature with normal head circumference (26.5%), diagnosis age less than 6 months (73.5%), seizure (37.2%) as the main symptom. The diagnosis was made by CT (61.7%). It was found that maternal age between age…15 and 20 years as well as birth weight less than 2500g are associated with cases of hydrocephalus. The diagnosis of Hydrocephalus, in children accompanied at the referred hospital, was performed mainly by CT scans, predominantly in children younger than 6 months and the seizure was the prevalent symptom and can be used as an alert.(AU)

Cerebrospinal fluid drainage options for posthemorrhagic hydrocephalus in premature neonates / Opções de drenagem liquórica em neonatos prematuros com hidrocefalia pós hemorrágica

ABSTRACT Objective The literature describes various cerebrospinal fluid (CSF) drainage techniques to alleviate posthemorrhagic hydrocephalus in preterm newborns; however, consensus has not been reached. The scope of this study was describing a case series of premature neonates with posthemorrhagic hydrocephalus and assessing the outcomes of different approaches used for CSF diversion. Methods A consecutive review of the medical records of neonates with posthemorrhagic hydrocephalus treated with CSF drainage was conducted. Results Forty premature neonates were included. Serial lumbar puncture, ventriculosubgaleal shunt, and ventriculoperitoneal shunt were the treatments of choice in 25%, 37.5% and 37.5% of the cases, respectively. Conclusion Cerebrospinal fluid diversion should be tailored to each case with preference given to temporary CSF drainage in neonates with lower age and lower birth-weight, while the permanent ventriculoperitoneal shunt should be considered in healthier, higher birth-weight neonates born closer to term.

RESUMO Objetivo A literatura descreve várias opções de drenagem liquórica (DL) para alivio da hidrocefalia pós-hemorrágica (HPH) em neonatos prematuros; contudo, não existe um consenso sobre a melhor abordagem. O escopo deste estudo foi descrever uma série de casos de neonatos prematuros, portadores de HPH, verificando os resultados de diferentes técnicas utilizadas para DL. Métodos Revisão consecutiva dos prontuários de neonatos com diagnostico de HPH submetidos a DL. Resultados Quarenta recém-nascidos prematuros foram incluídos. A punção lombar seriada (PL), a derivação ventriculosubgaleal (VSG) e a derivação ventrículo peritoneal (VP) foram o tratamento escolhido em 25%, 37,5% e 37,5% dos casos, respectivamente. Conclusão As opções de DL devem ser avaliadas caso a caso, sendo dada preferência às drenagens temporária em prematuros com idade e peso mais baixos ao nascer, enquanto o shunt definitivo (derivação VP) pode ser considerado naqueles prematuros mais saudáveis, com idade e peso superiores.

Neurological Outcome in Fetuses with Mild and Moderate Ventriculomegaly / Resultado neurológico em fetos com ventriculomegalia leve e moderada

Abstract Introduction Ventriculomegaly (VM) is one the most frequent anomalies detected on prenatal ultrasound. Magnetic resonance imaging (MRI) may enhance diagnostic accuracy and prediction of developmental outcome in newborns. Purpose The aim of this study was to assess the correlation between ultrasound and MRI in fetuses with isolated mild and moderate VM. The secondary aim was to report the neurodevelopmental outcome at 4 years of age. Methods Fetuses with a prenatal ultrasound (brain scan) diagnosis of VM were identified over a 4-year period. Ventriculomegaly was defined as an atrial width of 10- 15 mm that was further divided as mild (10.1-12.0 mm) and moderate (12.1-15.0 mm). Fetuses with VM underwent antenatal as well as postnatal follow-ups by brain scan and MRI. Neurodevelopmental outcome was performed using the Griffiths Mental Development Scales and conducted, where indicated, until 4 years into the postnatal period. Results Sixty-two fetuses were identified. Ventriculomegaly was bilateral in 58% of cases. A stable dilatation was seen in 45% of cases, progression was seen in 13%, and regression of VM was seen in 4.5% respectively. Fetal MRI was performed in 54 fetuses and was concordant with brain scan findings in 85% of cases. Abnormal neurodevelopmental outcomes were seen in 9.6% of cases. Conclusion Fetuses in whom a progression of VM is seen are at a higher risk of developing an abnormal neurodevelopmental outcome. Although brain scan and MRI are substantially in agreement in defining the grade of ventricular dilatation, a low correlation was seen in the evaluation of VM associated with central nervous system (CNS) or non-CNS abnormalities.

Resumo Introdução Ventriculomegalia (VM) é uma das anomalias mais frequente no ultrassom pre-natal. Ressonâncias magnéticas (RM) melhoram a precisão do diagnóstico e previsão do desenvolvimento em recém-nascidos. Objetivo A proposta deste estudo foi avaliar a correlação entre ultrassom e RM em fetos com leve e moderada VM isolada. O objetivo secundário foi reportar o resultado neurológico na idade de 4 anos. Métodos Fetos com diagnóstico pré-natal pelo ultrassom de VM foram identificados na idade de 4 anos. Ventriculomegalia foi definida como medida do átrio do ventrículo lateral entre 10-15 mm, a qual foi subdividida em leve (10,1-12,0 mm) e moderada (12,1-15,0 mm). Fetos com VM foram seguidos nos períodos pré-natal e pós-natal por ultrassom e RM. O resultado neurológico foi realizado usando a escala de desenvolvimento mental de Griffiths, quando indicada, até a idade de 4 anos. Resultados Sessenta e dois fetos foram identificados. Ventriculomegalia bilateral ocorreu sem 58% dos casos. Uma dilatação estável foi observada em 45%, progressiva em 13% e regressiva em 4,5% dos casos, respectivamente. Ressonância magnética fetal foi realizada em 54 fetos, e foi concordante com os achados do ultrassom em 85% dos casos. Desenvolvimento neurológico anormal foi observado em 9,6% dos casos. Conclusão Fetos nos quais ocorreu progressão da VM são de alto risco para desenvolvimento neurológico anormal. Apesar do ultrassom e da RM mostrarem substancial concordância na definição do grau de dilatação ventricular, uma baixa correlação foi vista na avaliação da VM associada ou não com anomalias do sistema nervoso central.

Evaluation of Aqueductal Patency in Patients with Hydrocephalus: Three-Dimensional High-Sampling-Efficiency Technique (SPACE) versus Two-Dimensional Turbo Spin Echo at 3 Tesla

OBJECTIVE: To compare the accuracy of diagnosing aqueductal patency and image quality between high spatial resolution three-dimensional (3D) high-sampling-efficiency technique (sampling perfection with application optimized contrast using different flip angle evolutions [SPACE]) and T2-weighted (T2W) two-dimensional (2D) turbo spin echo (TSE) at 3-T in patients with hydrocephalus. MATERIALS AND METHODS: This retrospective study included 99 patients diagnosed with hydrocephalus. T2W 3D-SPACE was added to the routine sequences which consisted of T2W 2D-TSE, 3D-constructive interference steady state (CISS), and cine phase-contrast MRI (PC-MRI). Two radiologists evaluated independently the patency of cerebral aqueduct and image quality on the T2W 2D-TSE and T2W 3D-SPACE. PC-MRI and 3D-CISS were used as the reference for aqueductal patency and image quality, respectively. Inter-observer agreement was calculated using kappa statistics. RESULTS: The evaluation of the aqueductal patency by T2W 3D-SPACE and T2W 2D-TSE were in agreement with PC-MRI in 100% (99/99; sensitivity, 100% [83/83]; specificity, 100% [16/16]) and 83.8% (83/99; sensitivity, 100% [67/83]; specificity, 100% [16/16]), respectively (p < 0.001). No significant difference in image quality between T2W 2D-TSE and T2W 3D-SPACE (p = 0.056) occurred. The kappa values for inter-observer agreement were 0.714 for T2W 2D-TSE and 0.899 for T2W 3D-SPACE. CONCLUSION: Three-dimensional-SPACE is superior to 2D-TSE for the evaluation of aqueductal patency in hydrocephalus. T2W 3D-SPACE may hold promise as a highly accurate alternative treatment to PC-MRI for the physiological and morphological evaluation of aqueductal patency.

Stages of tuberculous meningitis: a clinicoradiologic analysis

To determine the frequencies and percentages of various clinicoradiologic variables of tuberculosis meningitis [TBM] with reference to British Medical Research Council [BMRC] staging of the disease. A case series. Department of Neurology, Jinnah Postgraduate Medical Centre, Karachi, from October 2010 to September 2011. The study included 93 adult patients with the diagnosis of tuberculous meningitis [TBM] at the study place. Patients were divided in three groups according to British Medical Research Council [BMRC] staging of TBM. Different clinical and radiological findings were analyzed at different stages of the disease. Data was analyzed using SPSS [Statistical Package of Social Sciences] version 11.0. A majority of patients were found to be in stage-II disease at the time of admission. History of illness at the time of admission was more than 2 weeks in 50% of stage-I patients but around 80% in stage-II and stage-III patients. Neck stiffness was the most commonly reported finding in all stages. Cranial nerve palsies were higher in stage-III [75%] than in stage-II [43%] and in stage-I [24%] patients. Hydrocephalus and basal enhancement was the most frequently reported radiographic abnormalities. Duration of illness and cranial nerve palsies are important variables in the diagnosis of TBM stages and if TBM is suspected, empiric treatment should be started immediately without bacteriologic proof to prevent morbidity and mortality

Ultrasonographic fetal nomograms of anterior ventricular hemisphere ratio (AVHR) and posterior ventricular hemisphere ratio (PVHR) for early prenatal diagnosis of hydrocephalus.

Serial ultrasound scans were done in 150 fetuses between 14th to 22nd week of gestation to establish the nomograms of anterior ventricular hemisphere ratio (AVHR) and posterior ventricular hemisphere ratio (PVHR). Of 150 fetuses, 100 were in the high risk group for neural tube defect and 50 were in the control group. The study indicates that the value of AVHR decreases from 0.62 to 0.50 and PVHR from 0.60 to 0.50 between 14th to 22nd week of gestation. No statistical difference was observed in the values of AVHR and PVHR in high risk and low risk (control) cases (p > .001). The value of AVHR or PVHR greater than 0.5 after 18 weeks of gestation or more was considered pathological for hydrocephalus. In 2, out of 3 cases of hydrocephalus detected in our series, the value of AVHR and PVHR was 0.7 at 20 weeks and in the third case it was 0.6 at 18 weeks. All of these values were 3 SD above the normal for the period of gestation.