An unusual clinical presentation of bilateral schizencephaly

Summary We present a case with a characteristic magnetic resonance image (MRI) of bilateral open-lipped schizencephaly and atypical clinical presentation. The patient is still alive and in good health in her forties, she has never presented seizures, and although the motor dysfunction is well correlated with cerebral lobe involvement, neurobehavioral dysfunction is not proportional to the MR image of the cerebral malformation.

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Un cas inhabituel de schizencéphalie bilatérale

Résumé Nous présentons un cas de schizencéphalie bilatérale ouverte caractérisé par une présentation clinique atypique et une imagerie par résonance magnétique nucléaire caractéristique. La patiente est encore vivante, en bonne santé, à plus de 40 ans, elle n'a jamais présenté de crise comitiale et, bien que les troubles moteurs soient bien corrélés aux altérations cérébrales, les troubles neuro-comportementaux ne sont pas proportionnels aux images IRM de cette malformation cérébrale.

     

Neuroepidemiology of Porencephaly,Schizencephaly, and Hydranencephaly in Miyagi Prefecture,Japan

BackgroundNo population-based surveys of porencephaly, schizencephaly, and hydranencephaly have been conducted in Japan or other Asian countries. We performed a neuroepidemiologic analysis to elucidate the incidence of porencephaly, schizencephaly, and hydranencephaly in Miyagi prefecture, Japan, during 2007-2011.MethodsWe sent inquiry forms in February 2012 to three neonatal intensive care units, 25 divisions of orthopedic surgery in municipal hospitals, 33 divisions of pediatrics including one university hospital, municipal hospitals, pediatric practitioners, and institutions for physically handicapped children located in Miyagi prefecture. These covered all clinics related to pediatric neurology and orthopedic surgery in Miyagi prefecture. In the inquiry, diagnostic criteria for porencephaly, schizencephaly, and hydranencephaly were described and representative images of magnetic resonance imaging were shown. We obtained an 82% (27 of 33) response rate from the divisions of pediatrics, a 100% (3 of 3) response rate from the neonatal intensive care units, and a 68% (17 of 25) response rate from orthopedic surgery clinics. The magnetic resonance imaging scans of each patient were retrieved and inspected.ResultsFive, one, and two individuals developed porencephaly, schizencephaly, and hydranencephaly, respectively. The estimated incidence rates of porencephaly, schizencephaly, and hydranencephaly were 5.2 (95% confidence interval [CI], 0.6-9.8), 1.0 (95% CI, 0.0-3.1), and 2.1 (95% CI, 0.0-5.0) per 100,000 live births, respectively.ConclusionsThe prevalence rates of porencephaly, schizencephaly, and hydranencephaly at birth reported herein are compatible with results reported previously in the United States and European countries. The overall prevalence rate of these three diseases was 8.3 (95% CI, 2.6-14.1) per 100,000 live births.     

Epilepsy and anomalies of neuronal migration: MRI and clinical aspects

Neuronal migration disorders are the result of disturbed brain development. In such disorders, neurons are abnormally located. In diagnosing these conditions, magnetic resonance imaging is superior to any other imaging technique. This enables us to improve our knowledge of the clinical correlates of neuronal migration. With reference to migrational disorder, a retrospective study of all 303 patients with epileptic seizures referred for magnetic resonance imaging during a 3-year period was performed, 13 patients (aged 12-41, mean age 27) were identified. They represent 4.3% of the entire study group. Of the patients with known epilepsy, 6.7% and of the mentally retarded, 13.7% had migrational disorders. Four patients had schizencephaly as the dominant finding, one was classified as hemimegalencephaly, 2 had isolated heterotopias, and 6 had localized pachy- and/or poly-microgyria. The clinical pictures are complex. Ectopias of grey matter are recognised foci of epilepsy, but from an epileptological and a clinical viewpoint little attention has been given to these disorders. The present study shows that malmigration is not rare in epilepsy patients, especially not in the mentally retarded.     

Bilateral inferior insertion of lateral rectus muscles associated with schizencephaly

A 5-year-old boy with a large V-pattern exotropia is described. He has a background of congenital left hemiparesis associated with schizencephaly. At the time of surgery the lateral recti were found to be abnormally inferiorly positioned. Accordingly, both lateral rectus muscles were recessed 6.5 mm and supraplaced. A V-pattern exotropia persisted postoperatively with clinical overaction of the inferior obliques. To our knowledge this is the first known case of extraocular muscle abnormalities associated with schizencephaly.     

Computed tomography in migratory disorders of human brain development

Summary Computed tomographic findings in developmental brain anomalies are more easily classified when the system used is based on embryogenesis related to morphology. Analysis of computed tomographic findings in a series of 154 patients with brain anomalies (Chiari malformation not included) revealed that specific examples of abnormalities occurring in major stages of brain development may be recognized by computed tomography. This paper deals with a group of patients with abnormalities that reflect a disturbance in neuronal migration.     

脑裂畸形的CT诊断

目的探讨CT检查在脑裂畸形诊断中的价值。方法回顾性分析了15例脑裂畸形的CT表现及相关的临床资料，并进行了CT分型：融合型（Ⅰ型）和分离型（Ⅱ型），每型又分轻度（a）和重度（b）。结果15例脑裂畸形中共检出22条裂隙。融合型3例，分离型12例，其中Ⅰa型1例，Ⅰa＋Ⅰa型1例，Ⅰb型1例，Ⅱb型7例，Ⅱb＋Ⅱb型1例，Ⅱb＋Ⅱb＋Ⅱb型1例，Ⅱa＋Ⅱb型3例。可见软脑膜-室管膜缝（P—E缝）12例共14条裂隙，中间段狭窄，边缘内衬灰质。可见侧脑室憩室11例共13个憩窒：合并透叫隔缺如7例。结论脑裂畸形具有特征性CT表现，CT检查对该病的诊断和鉴别诊断具有十分重要的价值。     

Prenatal diagnosis of schizencephaly with 2D‐3D sonography and MRI

We report a case of schizencephaly diagnosed prenatally at 23 weeks of gestational age with two‐dimensional (2D) and three‐dimensional (3D) sonography and fetal brain MRI, confirmed by autopsy. The diagnostic method of choice is 2D transabdominal and transvaginal sonography, whereas additional 3D sonography and MRI may provide a better understanding of the pathology and related findings. © 2009 Wiley Periodicals, Inc. J Clin Ultrasound, 2009     

Telencephalic Flexure and Malformations of the Lateral Cerebral (Sylvian) Fissure

After sagittal division of the prosencephalon at 4.5 weeks of gestation, the early fetal cerebral hemisphere bends or rotates posteroventrally from seven weeks of gestation. The posterior pole of the telencephalon thus becomes not the occipital but the temporal lobe as the telencephalic flexure forms the operculum and finally the lateral cerebral or Sylvian fissure. The ventral part is infolded to become the insula. The frontal and temporal lips of the Sylvian fissure, as well as the insula, all derive from the ventral margin of the primitive telencephalon, hence may be influenced by genetic mutations with a ventrodorsal gradient of expression. The telencephalic flexure also contributes to a shift of the hippocampus from a dorsal to a ventral position, the early rostral pole of the hippocampus becoming caudal and dorsal becoming ventral. The occipital horn is the most recent recess of the lateral ventricle, hence most vulnerable to anatomic variations that affect the calcarine fissure. Many major malformations include lack of telencephalic flexure (holoprosencephaly, extreme micrencephaly) or dysplastic Sylvian fissure (lissencephalies, hemimegalencephaly, schizencephaly). Although fissures and sulci are genetically programmed, mechanical forces of growth and volume expansion are proposed to be mainly extrinsic (including ventricles) for fissures and intrinsic for sulci. In fetal hydrocephalus, the telencephalic flexure is less affected because ventricular dilatation occurs later in gestation. Flexures can be detected prenatally by ultrasound and fetal magnetic resonance imaging and should be described neuropathologically in cerebral malformations.     

Postnatal evaluation of schizencephaly by transfontanellar three-dimensional sonography

Schizencephaly is a rare anomaly of neuronal migration characterized by the presence of brain clefts that communicate with the lateral ventricles. Type I is characterized by clefts with fused lips or margins, not communicating with the subarachnoid space. Type II is characterized by longer clefts that communicate with the subarachnoid space. Neonatal diagnosis of schizencephaly on transfontanellar two-dimensional (2D) sonography is rare, with only 1 report in the medical literature. The major limitation of 2D sonography is its inability to assess neonatal prognosis. There are no reports on MEDLINE about the use of transfontanellar three-dimensional (3D) sonography in the assessment of schizencephaly. We present a case of type II schizencephaly diagnosed on the 29th week of gestation with 2D sonography and describe the main findings with 3D sonography in surface and transparency modes performed in the neonatal period via the fontanel.