Search

Die Dandy-Walker-Malformation ist die haufigste zerebrale Malformation. Sie ist definiert durch eine Hypoplasie und Aufwartsrotation des Vermis cerebelli, einer zystischen Erweiterung des 4. Ventrikels und insgesamt einer vergroserten hinteren Schadelgrube mit Kranialwartsverlagerung der lateralen Sinus, des Tentoriums und des Torcular Herophili. Diese Malformation wurde zuerst durch Dandy und Blackfan 1914, dann nochmals durch Taggart und Walker 1942 erganzt. Die heutige Bezeichnung als Dandy-Walker-Malformation wurde durch Bender 1954 eingefuhrt. Zusatzlich zu diesen klassischen Befunden ist die Dandy-Walker-Malformation durch andere Abnormalitaten und Malformationen des zentralen Nervensystems (ZNS) einschlieslich Balkenagenesie, Heterotopien, okzipitale Meningozelen, visuelle Defizite und Epilepsien gekennzeichnet. Neurogenetische und bildgebende Untersuchungen haben zu einem besseren Verstandnis dieser Malformationen gefuhrt.

A black and white female German Holstein calf showed a highly deformed cranium. The animal was not able to stand. Further findings were bilateral strabismus divergens and negative pupillary light reflexes. Magnetic resonance imaging and pathological-anatomical examination showed that the cerebrum was replaced to a high degree by the ventricle system filled with 1.5 liters of cerebrospinal fluid. The hemispheres of the cerebellum were ruptured by the dilated fourth ventricle. In addition, the vermis and pons were missing and fluid accumulation in the subarachnoidal space extending up to the first spinal cord segments was visible. Inbreeding was not detected in the 3-generation-pedigree. No other affected calves from the same parents were known at the farm. Chromosomal abnormalities could not be detected after examination of 30 metaphase spreads using a light microscope. Infections and parasitic diseases could be ruled out for this anomaly. Very rare defect alleles might have been involved in the development of these inborn defects.

Thromboembolic events in neonates are very rare. They are often associated with severe disease affecting the newborn or are secondary to central venous lines or arterial catheters. Most of the described cases of thromboses of the iliac or femoral arteries are associated with cardiac catheterisation or femoral invasive blood pressure monitoring. The relationship between single umbilical arteries and an increased incidence of structural and chromosomal anomalies is well known, but a higher rate of thromboembolic disease in infants with single umbilical arteries has not been described. Rt-PA (recombinant tissue plasminogen activator) has been successfully used in small studies and numerous case reports. To date controlled clinical trials giving guidelines for antithrombotic therapy using rt-PA are still lacking. We report the clinical course of a 700 g premature male, who was born by Caesarean section at 29 + 6 gestational weeks. On the fifth day the baby suffered from arterial thrombosis of the right pelvis axis. Antenatally a single umbilical artery was identified. Iliac arteries on the involved site appeared hypoplastic. Additionally, the prothrombin G20210A mutation was found. The patient was treated successfully using recombinant tissue plasminogen activator. In the case of a high risk of limb or organ loss due to arterial thrombosis, thrombolysis using rt-PA is justified. Appropriate rt-PA treatment has been studied for the adult but not the paediatric population. Hence, well-designed clinical trials are necessary to determine the pharmacokinetics and dynamics of thrombolytic agents in children.

A very severely retarded infant with a Dandy-Walker malformation was treated with valproate since the age of 6 months on account of infantile spasms. Three weeks after start of therapy dexamethasone was applied additionally because valproate was ineffective. Seventy-six days after initiation of valproate therapy the infant died with the clinical signs of fulminant valproate-associated hepatotoxicity despite the discontinuation of valproate. In combination with a febrile otitis media the child had been periodically restless and lethargic during the last week prior to liver coma. Activity of liver enzymes remained within normal limits up to two days before coma occurred. Analysis of valproate metabolites by gas chromatography/mass spectrometry yielded unusually high concentrations of the di-unsaturated metabolite E,E-2,3'-dien-valproate before and during liver failure. The concentrations of the main metabolites E-2-en-valproate und 3-keto-valproate remained within the usual range found during valproate therapy at steady state. The oxydation products 4-en-valproate and E-2,4-dien-valproate which are formed by alternative pathways and are considered to be hepatotoxic were detected in very low concentrations only. The application of carnitine, of antioxidants thought to improve the capacity of the free radical scavenger system (selen, vitamin E), and of N-acetylcysteine which can detoxify reactive drug metabolites could not prevent the fatal outcome.

A case of atypical short-rib polydactyly syndrome (Majewski) with severe cerebral malformations (infundibular hamartoma, Dandy-Walker cyst, aplasia of cerebellar vermis, etc.) is reported. This seems to be the first case so far described in the literature.

A case of Dandy-Walker-syndrome is presented, comparing the value of sonography and CT in intrauterine diagnosis. Together with a review of the literature of the subject, pathogenesis, morphology and prognosis in regard to the psychomotoric development are discussed.

Treatment of patients suffering from neurofibromatosis (NF) is aimed, first of all, at the esthetical and functional impairment caused by neurofibromas of the skin, whereas vascular alterations are only rarely given prime consideration in the choice of treatment alternatives. Thus, the removal of an aneurysmic dilatation of the internal carotid artery and its replacement by interposing an autogenous vein graft in a patient with extensive neurofibromatosis of the right neck region and concurrent Dandy-Walker syndrome is reported. The characteristics of this syndrome and the question of a possible relationship between both clinical entities are discussed.

The results of 293 examinations of the skull by sonography in 170 newborn are presented. In 73 patients the results could be compared with the findings on CT or at post mortem. In 48%, abnormal sonograms of the skull were obtained, due to congenital abnormalities, hydrocephalus or intracerebral bleeds. High accuracy and wide application make real time sonography the diagnostic procedure of first choice for the examination of the brain of the newborn. An attempt has been made to determine the optimum time for the examination and suitable intervals for follow-up.

Intracranial changes of newborns and young children can easily be discovered by modern sonography, especially as long as fontanelles are still open. Sonography of brain first should be done before computed tomography, encephalography and/or ventriculography are performed. Correspondence of most sonographic findings and computed tomography by other authors, is supporting reduction of CT-investigations in favour of sonography. We cannot agree with the idea that computed tomography should be the most important first investigation. Technical reasons as thick skull or closed fontanelles are making sonography impossible and computer tomography should be used. Special examples out of about 1100 Sonograms of skulls of children are demonstrating, that sonography of newborns and children is the method, which is cheap, without risk, less time consuming, and without any radiation stress.

In a newborn boy with hydrocephalus the computed tomography (CT) demonstrates hypoplastic hemispheres of the cerebellum, the inferior part of the vermis is lacking and the enlarged cisterna magna is directly communicating with the fourth ventricle. The ventricles 1--3 are markedly enlarged. Only the additional studies after the application of Metrizamide intrathecally could demonstrate the direct communication of the spinal CSF system with the fourth ventricle, determining the diagnosis: Dandy-Walker-Variant. The computed tomography-cisternography (CTC) is an important additional investigation with only minimal risks to the patient.

The so-called midline-malformations of the brain which include alterations of ventricles or arachnoid spaces formerly only were found by invasive procedures performed because of their various clinical signs. Since cranial computerized tomography is available, by this new noninvasive method all these disturbances can be diagnosed safely. The paper is referring to the most frequent and essential exponents of these midline-malformations together with their main features in anatomy, pathomorphology, clinical and radiological signs. The persistent performed cavities especially the cavum septi pellucidi, the cavum Vergae and the cavum veli interpositi, additionally the agenesis of the corpus callosum, the Dandy-Walker-syndrome and the Chiari-malformations are described by typical cases. In conclusion the reliability of diagnosis in all cases of midline-malformations will be mostly sufficient by plain axial computed tomograms due to very clearly defined unmistakable pictures.

25 of about 300 infants and children, who had been examined by magnetic resonance imaging since 1984, had a congenital malformation of the brain. Cystic malformations (e.g. arachnoid cysts) were the most frequent lesion. Other findings were: Arnold-Chiari malformation, septo-optic dysplasia, Dandy-Walker syndrome, agenesis of the corpus callosum, migration disorders. The multiplanar slice orientation and the good tissue contrast in magnetic resonance imaging supplied a clear diagnosis in all cases. Compared with other imaging modalities (CT, ultrasonography) the depiction of the morphology was superior in MR imaging in most cases.

Gray scale ultrasonography of the brain was performed in 93 infants with cerebral malformations. The most common malformation was the Chiari-malformation (56 children), characterized by the caudal displacement of the cerebellar vermis into the foramen magnum. The rest of the cerebellum, pons and medulla oblongata were displaced caudally and dysplastic. All children with Chiari-syndrome showed more or less severe hydrocephalus. The Dandy-Walker-malformation (3 children) was characterized by a huge retrocerebellar cyst communicating with the fourth ventricle. The cerebellar vermis was dysplastic. In alobar holoprosencephaly (2 children) a large singular midline ventricle could be shown. Both thalami and plexus chorioidei were fused in the midline. Absence of the falx cerebri, interhemispheric fissure, corpus callosum and septum pellucidum was characteristic for alobar holoprosencephaly. Stenosis of the Sylvian aqueduct (4 children) was characterized by enlarged lateral ventricles and third ventricle, whereas the fourth ventricle was normal in size. Porencephalic cysts (7 children) were spheric echofree lesions of various size, usually located symmetrically in both cerebral hemispheres. In hydranencephaly (4 children) both hemispheres were replaced by echofree space occupying bubbles. In 5 children with agenesis of the corpus callosum no corpus callosum could be demonstrated by sonography. Coronal sections displaced the typical bull's head shape, formed by the enlarged third ventricle and the side ventricles as well as randomly arrayed sulci around the lateral ventricles, which are pathognomonic for agenesis of the corpus callosum. Agenesis of the septum pellucidum (5 children) was characterized by fusion of the frontal horns of the lateral ventricles. One child with aneurysmatic malformation of the vein of Galen showed dilated sinus rectus and pulsations of a cyst, located behind the third ventricle. Pulsed doppler recording showed pulsatile arterial flow patterns within the cyst.

It is discussed if in intracranial tumors, especially in tumors of the posterior cranial fossa, a CT and/or a ventriculography should be practiced. We have made investigations of 134 patients, 93 of whom were children up to 14 years of age. Each case was undertaken computed tomography as well as ventriculography. The results are clearly demonstrating the superiority of computed tomography compared with ventriculography. Ventriculography is a surgical intervention stressing the patients, side-effects may occur, and sometimes serious complications are caused. Modern computed tomography is producing pictures of high quality, which are highly sufficient for neurosurgical intervention. Very rarely additional angiography has to be performed. The diagnosis of intracranial tumors can fully be established by computed tomography, whereas ventriculography is no longer necessary.

A group of surviving and deceased children with hydrocephalus occlusus are compared. More unfavorable prognostically is a location of the occlusion in the region of the fourth ventricle and subsequent occurrence of hydrocephalus.