MRI in aqueduct compression and obstructive hydrocephalus due to an ecstatic basilar artery

A Review of Cerebrospinal Fluid Circulation and the Pathogenesis of Congenital Hydrocephalus

The brain's ventricles are filled with a colorless fluid known as cerebrospinal fluid (CSF). When there is an excessive accumulation of CSF in the ventricles, it can result in high intracranial pressure, ventricular enlargement, and compression of the surrounding brain tissue, leading to potential damage. This condition is referred to as hydrocephalus. Hydrocephalus is classified into two categories: congenital and acquired. Congenital hydrocephalus (CH) poses significant challenges for affected children and their families, particularly in resource-poor countries. Recognizing the psychological and economic impacts is crucial for developing interventions and support systems that can help alleviate the distress and burden faced by these families. As our understanding of CSF production and circulation improves, we are gaining clearer insights into the causes of CH. In this article, we will summarize the current knowledge regarding CSF circulation pathways and the underlying causes of CH. The main causes of CH include abnormalities in the FoxJ1 pathway of ventricular cilia, dysfunctions in the choroid plexus transporter Na+-K+-2Cl- contransporter isoform 1, developmental abnormalities in the cerebral cortex, and structural abnormalities within the brain. Understanding the causes of CH is indeed crucial for advancing research and developing effective treatment strategies. In this review, we will summarize the findings from existing studies on the causes of CH and propose potential research directions to further our understanding of this condition.

Supraclinoid Internal Carotid Artery Dolichoectasia Causing Compression of the Prechiasmatic Optic Nerve

BACKGROUND AND IMPORTANCE

Intracranial arterial dolichoectasia (or dilatative arteriopathy) is characterized by abnormal elongation, tortuosity, or increase in diameter of at least one of the main cerebral vessels. Dolichoectasia can be found incidentally or can present with cranial neuropathies (including vision loss) or stroke. Here, we describe the presentation and open surgical treatment of a patient with dolichoectasia of the intracranial internal carotid artery (ICA) causing monocular vision loss.

CLINICAL PRESENTATION

A 73-year-old man presented with several months of progressive monocular vision loss and was found to have dolichoectasia of the supraclinoid ICA and subsequently underwent microsurgical decompression of the overlying affected optic nerve. The patient's postoperative convalescence was uncomplicated, and he had improvement in his right-sided monocular vision loss after surgery.

CONCLUSION

We present the case of a patient with dolichoectasia of the supraclinoid ICA causing compression of the optic nerve with resultant monocular vision loss. Timely microvascular decompression proves to be an effective technique for vision preservation in the setting of this rare pathologic entity.

Target Sign of Third Ventricle in Basilar Dolichoectasia with Multiple Clinical Presentations: A Case Report

Basilar dolichoectasia (BDE) is an uncommon anatomical variant usually detected incidentally or during stroke evaluation. BDE can occasionally become symptomatic and may present with stroke (infarct or hemorrhage), raised intracranial pressure due to obstructive hydrocephalus, or with cranial nerve palsies. We present a unique case of BDE presenting with obstructive hydrocephalus, stroke, and cranial nerve palsy in single patient and propose a radiological sign (target sign of third ventricle), which could aid in imaging diagnosis and further management.

Severe vertebrobasilar dolichoectasia as a cause of obstructive hydrocephalus: A case report

RATIONALE

Dolichoectasia of the vertebrobasilar artery is a vascular anomaly characterized by marked elongating, widening, and tortuosity of the arteries. Although this anomaly is usually asymptomatic, it may present with ischemic symptoms or mass effect involving brainstem or cranial nerves.

PATIENT CONCERNS

A 52-year-old male was admitted with headache and visual field defect.

DIAGNOSES

Computed tomography and magnetic resonance imaging showed noncommunicating hydrocephalus due to vertebrobasilar dolichoectasia.

INTERVENTIONS

The patient underwent right-side ventriculoperitoneal shunt.

OUTCOMES

The patient's symptoms improved gradually, although visual symptoms persisted.

LESSONS

Neurosurgeons need to keep in mind vertebrobasilar dolichoectasia as a rare cause of obstructive hydrocephalus for accurate diagnosis and swift treatment.

Current and emerging MR imaging techniques for the diagnosis and management of CSF flow disorders: a review of phase-contrast and time-spatial labeling inversion pulse

This article provides an overview of phase-contrast and time-spatial labeling inversion pulse MR imaging techniques to assess CSF movement in the CNS under normal and pathophysiologic situations. Phase-contrast can quantitatively measure stroke volume in selected regions, notably the aqueduct of Sylvius, synchronized to the heartbeat. Judicious fine-tuning of the technique is needed to achieve maximal temporal resolution, and it has limited visualization of CSF motion in many CNS regions. Phase-contrast is frequently used to evaluate those patients with suspected normal pressure hydrocephalus and a Chiari I malformation. Correlation with successful treatment outcome has been problematic. Time-spatial labeling inversion pulse, with a high signal-to-noise ratio, assesses linear and turbulent motion of CSF anywhere in the CNS. Time-spatial labeling inversion pulse can qualitatively visualize whether CSF flows between 2 compartments and determine whether there is flow through the aqueduct of Sylvius or a new surgically created stoma. Cine images reveal CSF linear and turbulent flow patterns.

Dolichoectasia of the vertebral basilar and internal carotid arteries: A case report and literature review

Background:

Dolichoectasia is a rare disorder of the cerebral vasculature consisting of vascular elongation, widening, and tortuosity, usually involving the vertebral and basilar arteries. Its neurological symptoms and signs are highly variable.

Case Description:

We present a case of dolichoectasia of the vertebrobasilar system in a patient with a long standing history of multiple falls. Repeat neuroimaging revealed an increase in size of the dolichoectatic segment. In addition, a new fusiform dilatation of the contralateral petrous segment of the internal carotid artery and isolated ventriculomegaly had developed.

Conclusion:

Vertebrobasilar dolichoectasia can cause multiple clinical manifestations, with hydrocephalus being less common. In addition, having dolichoectasia of both posterior and anterior circulation is extremely rare.

Vertebral and/or basilar dolichoectasia in human adult cadavers

BACKGROUND

Intracranial arterial dolichoectasia is a condition in which arteries demonstrate an increase in length and diameter, with the vertebrobasilar system being the most commonly affected segment. Because the criteria for and degree of vertebrobasilar dolichoectasia are usually established on three-dimensional time-of-flight MR angiography, we presented the results of an anatomic study of vertebrobasilar dolichoectasia cadaveric specimens.

METHOD

Examination was carried out on the brains of human adult cadavers, routinely dissected at the Institute of Forensic Medicine. Measurement of the outer diameter and length of vertebral and/or basilar arteries was performed using the ImageJ processing program.

RESULTS

There were 14 cases (14/216) of vertebral and/or basilar (dolicho)ectasia. Their classification into special (sub)types is made according to the basilar and/or vertebral diameter. The basilar length ranged from 32.91-59.37 mm, and the basilar outer diameter ranged from 3.51-8.92 mm in relation to the corresponding point of its measurement. The outer diameter of the vertebral arteries ranged from 0.67-5.91 mm. The Games-Howell post hoc test additionally showed that a basilar outer diameter of grade III and IV was significantly larger than in grade II (p < 0.05).

CONCLUSIONS

We noted a predisposition of males older than 40 years to arterial dolichoectasia in the vertebrobasilar system, independently from population group, as well as its asymptomatic appearance, independently from the presence of atherosclerotic plaques.

Aqueductal developmental venous anomaly as an unusual cause of congenital hydrocephalus: a case report and review of the literature

Introduction

Aqueductal stenosis may be caused by a number of etiologies including congenital stenosis, tumor, inflammation, and, very rarely, vascular malformation. However, aqueductal stenosis caused by a developmental venous anomaly presenting as congenital hydrocephalus is even more rare, and, to the best of our knowledge, has not yet been reported in the literature. In this study, we review the literature and report the first case of congenital hydrocephalus associated with aqueductal stenosis from a developmental venous anomaly.

Case presentation

The patient is a three-day-old, African-American baby girl with a prenatal diagnosis of hydrocephalus. She presented with a full fontanelle, splayed sutures, and macrocephaly. Postnatal magnetic resonance imaging showed triventricular hydrocephalus, suggesting aqueductal stenosis. Examination of the T1-weighted sagittal magnetic resonance imaging enhanced with gadolinium revealed a developmental venous anomaly passing through the orifice of the aqueduct. We treated the patient with a ventriculoperitoneal shunt.

Conclusions

Ten cases of aqueductal stenosis due to venous lesions have been reported and, although these venous angiomas and developmental venous anomalies are usually considered congenital lesions, all 10 cases became symptomatic as older children and adults. Our case is the first in which aqueductal stenosis caused by a developmental venous anomaly presents as congenital hydrocephalus. We hope adding to the literature will improve understanding of this very uncommon cause of hydrocephalus and, therefore, will aid in treatment.

Dolichoectasia of vertebrobasilar arteries as a cause of hydrocephalus

Dolichoectasia of vertebrobasilar artery is a condition in which the vertebral/basilar artery is elongated, distended and tortuous. It is usually asymptomatic. It may present with compressive or ischemic symptoms. Hydrocephalus as a complication of vertebrobasilar dolichoectasia is rare. We present a case of a 60-year-old male with dolichoectasia of the basilar artery causing compression of the third ventricular outflow and, thus, presenting with noncommunicating hydrocephalus.

[Relations of aqueduct with some structures of mesencephalon]

INTRODUCTION

Aqueductus mesencephali is the biggest part of the ventricular system and that is why it is the most common place of intraventricular obstruction of cerebrospinal fluid. This study was done in order to study topographic characteristics of aqueduct more thoroughly.

MATERIALS AND METHODS

Transversal sections of mesencephalon were made in three levels. The first section was made caudally immediately from the posterior commissure. The second section was made in the middle part of the superior colliculi, and the third section was made in the rostral parts of the caudal sections of the superior colliculi. Distances of the aqueduct from structures of mesencephalon, obtained on the second section, are: 1. The distance of the aqueduct from the superior colliculi - 6.96 mm; 2. The distance of the aqueduct from the red nucleus - 6.02 mm; 3. The distance of the aqueduct from the substantia nigra - 12.29 mm; 4. The distance of the aqueduct from the interpeduncular fossa - 10.22 mm.

CONCLUSION

Knowledge of the anatomy of the aqueductus mesencephali is very important because of interpretation of patogenesis of hidrocefalus as well as of other syndromes that occure in some pathological processes in the system of ventricles.

Enlarged thalamostriate vein causing unilateral Monro foramen obstruction. Case report

Causes of unilateral hydrocephalus resulting from an obstruction at the Monro foramen include foraminal atresia, tumors, gliosis, contralateral shunting, and infectious and inflammatory conditions. However, few reports in the literature cite vascular lesions as the cause of the obstruction. To their knowledge, the authors present the first report of unilateral hydrocephalus occurring due to an abnormally enlarged thalamostriate vein independent of an arteriovenous malformation or developmental venous angioma. The condition was treated successfully by endoscopic septum pellucidum fenestration. A 28-year-old man was referred for evaluation due to a 10-year history of chronic headaches that worsened in severity over the past year. A CT scan of the head revealed unilateral right ventricular dilation. Cranial MR imaging with and without contrast administration showed a dilated right thalamostriate-internal vein complex without any evidence of associated arteriovenous malformation or venous angioma. Endoscopic exploration of the right lateral ventricle showed an enlarged subependymal thalamostriate vein obstructing the Monro foramen. An endoscopic fenestration of the septum pellucidum was performed, resulting in alleviation of the patient's symptoms. Abnormally enlarged venous structures may cause obstructive unilateral hydrocephalus and can be a rare cause of chronic, intermittent headaches in adults. Endoscopic fenestration of the septum pellucidum is an effective treatment.

A histological study of cerebral aqueduct

Cerebral (sylvian) aqueduct is a narrow channel in the mesencephalon. It lies between the tectum and the tegmentum of the mesencephalon and is surrounded by the periaqueductal gray matter. The aim of this study was to determine the shape of the aqueduct of sylvius and the structure of its walls in a series of transverse histological sections. Serial transverse sections of the mesencephalon were examined in twenty adult brains of both sexes. Six sections were stained by the hematoxylin-eosin method. The rostral part of the the aqueduct has a triangular shape with dorsal concavity caused by retrocommissural fossae. In the middle, its shape is oval to irregular, the rostral part has a T shape due to isthmic recess on the floor. Walls of the aqueduct are coated with a layer of prismatic cells. Determination of the morphological and histological features of the mesencephalic aqueduct is important for differentiation between physiological and pathological processes in this region.