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At least 19 recordsLinked to original sources
PubMed1977

Membranous occulusion of the aqueduct of Sylvius.

Two cases of membranous occlusion of the aqueduct of Sylvius are presented. The role of Conray ventriculography in the precise diagnosis of this condition is stressed. Both cases have been operated upon, and the membranes perforated by catheterisation. The catheter was left in the aqueduct in one case. One of the patients was cured, the other died. Membranous occlusion of the aqueduct of Sylvius is a rare cause of hydrocephalus. Occurrence of two cases within a four-month period attracted our attention to this disorder.

Adolescent↗
PubMed1999

Autosomal recessive hydrocephalus due to congenital stenosis of the aqueduct of sylvius.

Isolated hydrocephalus due to congenital stenosis of the aqueduct of Sylvius is almost always an X-linked recessive inherited condition. We describe a brother and sister with isolated hydrocephalus from congenital aqueductal stenosis. We believe that these two occurrences represent a rare autosomal recessive form of this abnormality. In assessing a first known occurrence of hydrocephalus with stenosis of the aqueduct of Sylvius in a family, the rare possibility of autosomal inheritance must be considered in genetic counselling.

Abortion, Therapeutic↗
PubMed2006

Computational investigation of subject-specific cerebrospinal fluid flow in the third ventricle and aqueduct of Sylvius.

The cerebrospinal fluid flow in the third ventricle of the brain and the aqueduct of Sylvius was studied using computational fluid dynamics (CFD) based on subject-specific boundary conditions derived from magnetic resonance imaging (MRI) scans. The flow domain geometry was reconstructed from anatomical MRI scans by manual image segmentation. The movement of the domain boundary was derived from MRI brain motion scans. Velocimetric MRI scans were used to reconstruct the velocity field at the inferior end of the aqueduct of Sylvius based on the theory of pulsatile flow in pipes. A constant pressure boundary condition was assigned at the foramina of Monro. Three main flow features were observed: a fluid jet emerging from the aqueduct of Sylvius, a moderately mobile recirculation zone above the jet and a mobile recirculation below the jet. The flow in the entire domain was laminar with a maximum Reynolds number of 340 in the aqueduct. The findings demonstrate that by combining MRI scans and CFD simulations, subject-specific detailed quantitative information of the flow field in the third ventricle and the aqueduct of Sylvius can be obtained.

Adult↗
PubMed2002

The impact of hypercapnia on systolic cerebrospinal fluid peak velocity in the aqueduct of sylvius.

UNLABELLED: Phase-contrast magnetic resonance imaging measurements of systolic cerebrospinal fluid peak velocity (CSFVPeak) in the aqueduct of Sylvius have been shown to be sensitive enough to detect even minor changes in cerebral compliance. Clinically relevant changes in cerebral compliance can be caused by changes in cerebral blood volume (CBV). Changes in arterial carbon dioxide partial pressure, which correlate well with end-tidal carbon dioxide concentration (ETCO(2)), cause changes in CBV. In this study, we investigated the effect of hypercapnia-induced changes in CBV on systolic CSFVPeak in anesthetized patients (n = 8). Hypercapnia (ETCO(2) = 60 mm Hg) increased systolic CSFVPeak in the aqueduct of Sylvius as compared with normocapnia (ETCO(2) = 40 mm Hg) (hypercapnia: -5.67 +/- 0.74 cm/s versus normocapnia: -3.54 +/- 0.98 cm/s). In addition to the already known decrease in systolic CSFVPeak, changes in cerebral compliance can also prompt an increase in systolic CSFVPeak. IMPLICATIONS: Magnetic resonance imaging measurements of systolic cerebrospinal fluid peak velocity (CSFVPeak) in the aqueduct of Sylvius are sensitive enough to detect even minor changes in cerebral compliance. We investigated the effect of hypercapnia-induced changes in cerebral blood volume on systolic CSFVPeak in anesthetized patients. Hypercapnia (end-tidal carbon dioxide concentration = 60 mm Hg) increased systolic CSFVPeak.

Adult↗
PubMed1989

[Clinical aspects and therapy of adult hydrocephalus associated with stenosis of the aqueduct of Sylvius].

The author describes 11 cases of adult hydrocephalus based on stenosis of the aqueduct of Sylvius. She describes clinical manifestations and diagnostic possibilities. CT examination and positive VG are most useful for the diagnosis. Clinical signs of rising intracranial pressure, considerable narrowing of or absence of the filling of the aqueduct and hydrocephalus are in the author's opinion the most important criteria of operation. Recanalization of the aqueduct of Sylvius by a drainage tube according to Bret is the optimal surgical approach.

Adult↗
PubMed1981

Stereotaxic reconstruction of the aqueduct of Sylvius.

A stereotaxic technique has been developed to cannulate the cerebral aqueduct in patients with hydrocephalus resulting from occlusion of the aqueduct of Sylvius. Precise placement of a 15- to 20-mm long radiopaque prosthesis between the third and fourth ventricles can reestablish the normal cerebrospinal fluid (CSF) pathway. Since 1974, seven patients have undergone aqueductal reconstruction. The surgical goal in this series was to manage the hydrocephalus by creating and maintaining a patent aqueductal channel. The follow-up period ranged from 1.5 to 6.5 years. In four cases, aqueductal reconstruction alone resulted in control of the hydrocephalus, although two patients underwent revisions of their prosthesis. Three patients ultimately required shunts, despite initial symptomatic improvement after reconstruction. In these seven cases (13 stereotaxic procedures), no mortality and no significant operative morbidity were encountered. Although the technique is relatively simple to perform, technical difficulties remain. At present, no clinical or radiographic test adequately discerns the ideal candidate for stereotaxic aqueductal reconstruction. Four patients required stereotaxic revision because of malposition or malfunction of the prosthesis. This approach should be reserved for patients with a short aqueductal occlusion, and normal distal CSF pathways and dynamics. The rationale, technique, problems, and results of stereotaxic reconstruction are presented.

Adolescent↗
PubMed2006

Semiautomatic analysis of phase contrast magnetic resonance imaging of cerebrospinal fluid flow through the aqueduct of Sylvius.

OBJECTIVE: Quantification of the cerebrospinal fluid (CSF) flow through the aqueduct of Sylvius by means of magnetic resonance imaging (MRI) is subject to interobserver variability due to the region of interest (ROI) selection. Our objective is to develop a semiautomatic measurement method to achieve reproducible quantitative analysis of CSF flow rate and stroke volume. MATERIAL AND METHODS: MR examinations were performed using a 1.5 T scanner with a phase contrast sequence (velocity encoding [V(enc)] of 20 cm/s, FOV = 160, 3 mm slice thickness, image matrix size = 256x256, TR = 53 ms, TE = 11 ms, NSA = 2, flip angle = 15 degrees and 23 frames per cardiac cycle with peripheral retrospective pulse gating). Our method was developed using MATLAB R7. Errors introduced by background offset and possible aliased pixels were automatically detected and corrected if necessary in order to calculate the flow parameters that characterize CSF dynamics. The semiautomatic seed method reproducibility was evaluated and compared with the radius method by two observers analysing 21 healthy subjects. RESULTS: The measurements using the semiautomatic seed method reduced the interobservers variability (intra-class correlation [ICC] = 1.0 for stroke volume and for volumetric flow rate) versus the radius method (ICC = 0.46 for stroke volume and 0.65 for flow rate). Normal stroke volume (39.19 +/- 20.13 microl/cycle), flow rate (3.81 +/- 2.81 ml/min), maximal mean systolic velocity (5.27 +/- 1.3 cm/s) and maximal mean diastolic velocity (4.20 +/- 1.4 cm/s) were calculated with the half moon and aliasing corrected seed method. CONCLUSIONS: Semiautomatic measurements (seed method with half moon background and aliasing correction) allow a generalization of the calculus of flow parameters with great consistency and independency of the operator.

Algorithms↗
PubMed1987

[Congenital stenosis of the aqueduct of Sylvius transmitted in an autosomal recessive mode (5 cases in 2 families)].

The authors report 5 cases of congenital hydrocephalus due to isolated stenosis of the aqueduct of Sylvius. In the first three cases (2 brothers and 1 sister) ventriculograms showed apparent obstruction of the aqueduct. A valve shunting was necessary at 1 month of age in cases 1 and 2, at 3 years of age in case 3. In cases 4 and 5 (1 brother and 1 sister) ultrasonic prenatal diagnosis showed ventriculomegaly and pregnancies were interrupted respectively at 31 and 28 weeks of gestational age. The pedigree of the families suggests that the inheritance of this abnormality is autosomal recessive. Such an inheritance is very unusual and confirms the difficulty of genetic counseling facing the first occurrence of hydrocephalus with stenosis of the aqueduct of Sylvius in a family. The prenatal diagnosis is based on fetal ultrasonic examination and may be obtained late in the pregnancy leading to therapeutic and ethical tricky decisions.

Abortion, Therapeutic↗
PubMedDate not supplied

Neuroophthalmological symptoms in children treated for internal hydrocephalus.

The object of the study are 126 children with internal hydrocephalus treated within the period 1978-1990. The children were preoperatively divided into six groups according to the etiology of the hydrocephalus. Disorders of the visual functions accompanying elevated intracranial pressure (setting sun 51, syndrome of the aqueduct of Sylvius 14, paresis of craniocerebral nerves 9, nystagmus 8, optic atrophy 4) were established preoperatively in 48.4% of the children. 44 of the children were revised because of malfunction of the shunt with the following neuroophthalmological symptoms: setting sun 6, paresis of craniocerebral nerves 9, syndrome of the Sylvius aqueduct 6, papilledema 6, optic atrophy 9 and nystagmus 5. The fact that a great many changes in the visual functions sometimes precede the manifestations of the changes in CT image determines their significance for early diagnosis and treatment.

Cerebrospinal Fluid Shunts↗
PubMed1993

Prenatal exclusion of X-linked hydrocephalus-stenosis of the aqueduct of Sylvius sequence using closely linked DNA markers.

X-linked hydrocephalus-stenosis of the aqueduct of Sylvius sequence (H-SAS, MIM number 307,000) is a rare genetic disorder characterized by hydrocephalus, macrocephaly, adducted thumbs, spasticity, mental retardation, and cerebral malformations. This regularly lethal condition is usually diagnosed at birth or prenatally by ultrasound, but hydrocephalus may be moderate or even undetectable on fetal ultrasound examination. Moreover, since heterozygous women are asymptomatic, carrier detection is at present impossible before the birth of an affected son. Therefore, mapping the H-SAS locus to distal Xq (Xq28) was of primary importance for genetic counselling and prenatal diagnosis. Here, we report prenatal exclusion of H-SAS with a probability of 97.6 per cent in two male fetuses with a 50 per cent a priori risk of being affected using closely linked Xq28 DNA markers.

Cerebral Aqueduct↗
PubMed2004

Congenital idiopathic intestinal pseudo-obstruction and hydrocephalus with stenosis of the aqueduct of sylvius.

We present the first report of an association between hydrocephalus with stenosis of the aqueduct of Sylvius (HSAS) and a specific form of congenital idiopathic intestinal pseudo-obstruction (CIIP) in an infant. Diagnosis of HSAS was suspected during the neonatal period because of a severely dilated ventricular system associated with bilateral adducted thumbs, and was confirmed by demonstration of a mutation in the gene encoding L1 cell adhesion molecule (L1CAM). L1CAM mutations cause a variable clinical spectrum. This gene is located at Xq28 and encodes a transmembrane glycoprotein involved in neurite outgrowth and neuronal migration. Hirschprung disease has been reported to involve an L1CAM mutation that manifests as a quantitative defect in the migration of neural crest cells in distal segments of the gut. We report an association that suggests that alterations of L1CAM may cause another type of intestinal pseudo-obstruction distension with a qualitative defect in differentiated Cajal's cells in the anterior part of the gut. This observation suggests that L1CAM has a role in the developmental regulation of multiple systems. Further clinical descriptions of gastroenterological and neuropathological data are required to extend our understanding of the mechanisms underlying L1CAM functions.

Cerebral Aqueduct↗