Clinical evaluation of an isolated fourth ventricle

Since the introduction of the CT scan in 1976, we have experienced 6 cases of the isolated fourth ventricle among 244 hydrocephalic patients (2.5%). Age at diagnosis of the isolated fourth ventricle ranged from 1 year 8 months to 13 years (mean age, 8 years, 6 months). The time interval between the first shunting procedure and the diagnosis of the isolated fourth ventricle varied from 1 year 5 months to 7 years 4 months (mean interval, 4 years 1 months). The prior hydrocephalus were due to intraventricular hemorrhage in two patients, meningomyelocele in a patient and brain tumor in three patients. Two patients had history of cerebrospinal fluid (CSF) infection and five cases underwent multiple shunt revisions. Posterior fossa signs were evident in all cases. It was quite easy to make a diagnosis of the isolated fourth ventricle with CT scan, which demonstrated a large rounded or pear-shaped midline cyst in the posterior fossa. Slit-like lateral ventricles were noted in three cases, while the remaining three had enlarged lateral ventricles. Ventriculography confirmed the isolation of the fourth ventricle in 5 cases. Metrizamide which had been injected into the fourth ventricle was diluted when CT scan was performed 48 hours later, and contrast medium disappeared since then. Magnetic resonance imaging (MRI) well showed the characteristic findings of the isolated fourth ventricle: cystic dilatation of the fourth ventricle, compression and distortion of the brain stem, upward tentorial herniation, occlusion of the aqueduct, downward displacement of the occipital lobe, septum formation of the fourth ventricle and accompanied anomalies such as, Chiari malformation or syringomyelia.(ABSTRACT TRUNCATED AT 250 WORDS)     

Large infratentorial multilocular arachnoid cyst

Clinical and radiological findings in a 2-year-old boy with a large multilocular infratentorial arachnoid cyst are presented. The cyst was extended in the bilateral paracollicular and retrocerebellar region and was communicating with each other but not with the ventricular system. Associated with those cysts was a significant degree of hydrocephalus due to compression of the fourth ventricle. Delayed metrizamide CT scan showed totally isolated cysts from CSF circulation although the cystic content was determined as the CSF.     

Mesencephalic and third ventricle cysts: diagnosis and management in four cases.

Four infants with obstructive hydrocephalus caused by space occupying third ventricle and mesencephalic cysts are reported. Despite immediate shunt insertion in all patients, there was either lack of clinical improvement or late onset of clinical deterioration. Neuroimaging (CT, MRI, and ventriculography) diagnosed the presence of non-communicating midline outpouchings of the CSF pathways causing obstruction of aqueductal CSF flow and brainstem signs. The cysts were of different origin. In one patient it was caused by a previous thalamic haemorrhage, in another patient by neonatal Escherichia coli meningoventriculitis. In two cases with obstructive hydrocephalus at birth, the aetiology is unclear. Direct puncture and drainage of the cysts led to clinical improvement. The cysts were poorly visualised on CT and could be misinterpreted as an enlarged third ventricle, simulating congenital aqueduct stenosis. Careful neuroradiological investigation is necessary to establish an accurate diagnosis and neurosurgical management. In such cases with hydrocephalus and persisting ventricular enlargement despite shunting, CT ventriculography is a useful tool.     

Pediatric metrizamide CT cisternography and CT ventriculography (author's transl)]

We have studied the diagnostic value of computed tomography with metrizamide CSF enhancement in 37 infants. According to the method of injection, we called CT cisternography, CT ventriculography and CT cystography. These methods were useful for the morphologic and dynamic evaluation of the CSF pathways. We used them especially for the evaluation of hydrocephalus, skull base tumor, infantile subdural hematoma and its allied diseases, or congenital cystic lesion such as Dandy-Walker syndrome. The side effects in children are much less than those in adults.     

Computerized tomography in patients with neurocysticercosis with intracranial hypertension due to obstructive hydrocephalus: comparison with Dimer-X ventriculography

The authors reviewed the alterations observed on computerized tomography (CT) examinations of 16 patients with increased intracranial pressure and obstructive hydrocephalus due to cerebral cysticercosis. Plain radiograms of the skull were available in all cases and Dimer-X ventriculography in 12 cases. In 7 cases there were radiologic signs of increased intracranial pressure. CT scan showed normal cerebral parenchyma in 9 cases and low density areas, with various size, with or without surround contrast enhancement, and/or small calcifications in the parenchyma. Hydrocephalus was the only alteration observed in the ventricular system in the case that the examination was done before ventricular drainage. Ventriculography was analyzed in other paper and permitted to situate the obstruction, determine its morphological characteristics and identify occuping space lesions within the ventricles. Comparison between ventriculography and CT scan made in the same period evidence that the former gives best information about the ventricular system and that tomography gives additional information about the cerebral parenchyma. In conclusion, CT scan and ventriculography are investigations that complete each the other for evaluation and diagnosis of cerebral cysticercosis.     

A case of subtentorial ventricular diverticulum accompanied with choroid plexus papilloma in the lateral ventricle

Marked non-communicating hydrocephalus may rarely cause ventricular rupture producing either a dilated cystic cavity (ventricular diverticulum) or communication between ventricle system and subarachnoid space (spontaneous ventriculostomy). Ventricular diverticulum has been believed to be collection of cerebrospinal fluid which escaped beneath the pia mater after rupture of ependymal layers and cerebral parenchyma. We proposed herein to report a case of subtentorial ventricular diverticulum which accompanied with choroid plexus papilloma of the lateral ventricle. A nine year-old girl admitted to our hospital complaining of clumsiness of hands and walking, disability of reading, headache and vomiting. The neurological examination revealed alexia, papilledema, anisocoria, righ hemianopsia, weakness of right upper limb, and cerebellar ataxia. CT brain scan showed a large high density area at the trigone of the left lateral ventricle with non-communicating hydrocephalus and an extra-axial low density area in the posterior fossa. The medial space of the left trigone was especially ballooned and is just shifted above incisura tentoria by the tumor. The intraventricular tumor was totally removed by operation and proved to be benign choroid plexus papilloma microscopically. The subtentorial mass was confirmed to be a cyst contiguous to the medial trigone of the lateral ventricle, namely ventricular diverticulum. Three special features were recognized in this case. The first, this was the first example of ventricular rupture accompanied with tumor in the lateral ventricle reviewing all reports of both ventricular diverticulum and spontaneous ventriculostomy. The second, this ventricular diverticulum was not produced merely by hydrocephalus alone but mainly by direct effects of the tumor.(ABSTRACT TRUNCATED AT 250 WORDS)     

Normal pressure hydrocephalus. Part 1. Dynamic study of CSF circulation in patients with normal pressure hydrocephalus (author's transl)

To clarify the pathogenesis of normal pressure hydrocephalus (NPH), quantitative measurement of CSF dynamics was attempted using RI techniques. In this study results concerning RI ventriculography and RI transfer test from CSF to plasma were reported. "Barrier ratio" and regional cerebral blood flow study in NPH will be reported elsewhere. Fifty-three patients with chronic communicating hydrocephalus wer devided into two groups. Thus, twenty-seven cases were diagnosed as NPH according to clinical symptoms and signs, and others were considered as mere chronic communicating hydrocephalus without any NPH characteristics. Results are as follows: 1) 169Yb--DTPA ventriculography; In NPH group, there was longer retention of RI injected into lateral ventricle, and RI activity was not detected in the cisterna magna 60 minutes after the injection. These findings show remarkable delay of CSF flow in NPH patients. 2) Transfer test of 169Yb--DTPA from CSF to plasma; Immediately after the RI injection, Transfer ratio of RI activity from CSF to plasma was measured. It was revealed that intraventricular RI was more rapidly transfered to plasma in NPH group compared with in the control group, suggesting accelerated trans-ependymal absorption of RI in NPH group.     

Moyamoya病的临床表现与影像学特点

目的 回顾分析12例Moyamoya病的临床和影像学特征，探讨Moyamoya病的影像学诊断价值。方法 分析12例Moyamoya病患的临床资料及数字减影血管造影(DSA)、磁共振血管造影(MRA)、磁共振成像(MRI)和CT结果。结果 所有病例均表现有颈内动脉或其分支不同程度的狭窄或闭塞和颅底异常血管网(MMD血管)；其中病变呈双侧8例．单侧4例。12例中头颅CT表现有梗塞灶4例，脑出血5例，其余3例表现正常。结论 除DsA外．MRI和MRA是两种可以很好评价Moyamoya病的影像学方法。若儿童或青壮年发生脑血管病，反复出现脑梗死或出现脑室出血、脑叶出血或蛛网膜下腔出血(SAH)则要考虑Moyamoya病的可能。     

Non-invasive radiological investigation for oculomotor palsy.

An application of computed tomography (CT) is described in which multiplanar high resolution images of the terminal carotid and basilar arteries are obtained. This has been applied in a series of 32 patients with IIIrd nerve palsy in whom the underlying pathology was thought to be a posterior communicating artery aneurysm. The results of the CT were compared with conventional angiography. Seventeen aneurysms were detected in 13 patients by CT and all were confirmed by angiography. Vessels considered to be normal on CT were confirmed to be normal by angiography. This CT technique is a simple non invasive first line investigation for IIIrd nerve palsy with the ability to exclude or predict an aneurysm.     

Choroid plexus cyst of the left lateral ventricle with intermittent blockage of the foramen of Monro, and initial invagination into the III ventricle in a child

A cyst of the choroid plexus of the left lateral ventricle with intermittent blockage of the foramen of Monro and initially with invagination of the III ventricle in a child is described. In a 6-week-old boy a ventriculoatrial shunt was implanted for correction of an active asymmetrical hydrocephalus of unknown origin. When he was 3 months of age a water-soluble contrast CT ventriculography revealed a noncolloid cyst localised predominantly in the upper portion of the III ventricle. At that time the ventricular catheter obstructed with choroid plexus was removed; new bilateral catheters in a parieto-occipital region were implanted. In the course of the next 4 years, first the atrial catheter had to be extracted and then the peritoneal catheter was changed, in both cases because of obstruction. Periods of normal life alternated with periods of transient and intermittent symptoms of increased intracranial pressure, papilloedema, and myoclonic jerks. Repeated computed tomography (CT) and magnetic resonance imaging (MRI) showed stabilised hydrocephalus with an enlarged left lateral ventricle. When the boy was 16 years old MRI revealed a choroid plexus cyst in the left lateral ventricle 2 cm in diameter, with a ball-valve type of obstruction of the foramen of Monro. CT stereoendoscopic resection of the wall of a large cyst filled with cerebrospinal fluid was performed, and two additional adnexal small cysts were coagulated using the bipolar coagulator, Diomed 25 laser and scissors; the symptoms then regressed, except for superior bilateral altitudinal anopsia. Light and electron microscopy of the cyst wall is reported. The cyst was composed of collagenic connective tissue lined with a basal lamina lacking in epithelial cells. The preoperative and postoperative MRI are presented. Choroid plexus cysts localised in the anterior part of lateral ventricles are very rare, and all reported cases have been in male patients. According to the literature our case is only the third ever described in a child. Received: 9 March 1998 Revised: 12 May 1998     

Chronic subdural hematoma presenting visual disturbance: a case report]

The authors reported a rare case of chronic subdural hematoma presenting bilateral visual impairment caused by papilledema. A 49-year-old man was admitted to our department due to left blurred vision. On admission, ophthalmological examination revealed visual acuity disturbance on the left eye, bilateral nasal visual field defect and papilledema. CT scan and MRI demonstrated bilateral subdural hematoma. No remarkable findings were detected on cerebral angiography. After evacuation of bilateral subdural hematomas, his visual symptoms recovered. In this report, we discuss the mechanism of visual impairment caused by chronic subdural hematoma.     

Visual field defects in hydrocephalus

Eight patients representing visual field defects associated with hydrocephalus are reviewed. Seven cases had aqueductal stenosis and one had congenital communicating hydrocephalus. We found five cases of defects in visual field typical of a chiasmal or optic nerve lesion: (1) inferior altitudinal hemianopia with inferior nasal quadrantanopia in the opposite eye; (2) inferior binasal quadrantanopia; (3) unilateral inferior nasal depression; (4) unilateral temporal defect; (5) bilateral central scotoma. In these cases CT demonstrated moderate or marked symmetrical dilatation of the third and lateral ventricles. Four out of five cases showed bulging of the third ventricle anteriorly into the sella turcica on CT or ventriculography. Other three patients had incongruous homonymous hemianopia. Characteristic asymmetrical dilatation of the lateral ventricles was noted in all three cases. The more enlarged lateral ventricles were ipsilateral with the affected visual pathways. The sites of lesion responsible for these field defects seemed to be optic tract in one case and optic radiation in two cases. Ventriculoperitoneal shunt was placed in five out of seven cases. Impaired visual field improved in three patients after shunt insertion. A 28-year-old female who had history of blurred vision fos 14 days showed improvement in visual acuity and field when the enlarged ventricles became slit-like by shunting. In the other two patients defects in visual fields improved in spite of consistent ventriculomegaly. These facts suggested that not only the mechanical forces with distended third ventricle but also increased intracranial pressure played an important role in producing visual field defects in hydrocephalic patients.     

Ultrasonographic evaluation of infantile hydrocephalus before and after shunting

The authors present the results of a prospective study of 20 children with congenital or acquired hydrocephalus of nontumoral etiology and submitted to ventriculo-(or cyst-) peritoneal shunting with valve. The diagnosis was established by B-mode or real-time brain sonography, in association with another neuroradiological procedure (computed tomography, ventriculography with air or Dimer-X, cerebral angiography). Among the proposed measurements (cortical thickness, lateral ventricle height, III ventricle width and ventricular ratio) for pre- and postoperative comparison, the cortical thickness and the lateral ventricle height were the ones that changed significantly when analyzed by sonography. The routine use of brain sonography allowed the visualization of the ventricular catheter position and the diagnosis of complications, such as subdural collection, progressive enlargement of cysts, isolated IV ventricle, etc, even before symptoms arise. The authors conclude that sonography is easily performed, inexpensive and innocuous, and should be used routinely during the follow-up of children with hydrocephalus.     

Angiographic findings of ischemic stroke in children

A cooperative study was undertaken in the Tohoku district of Japan to investigate the relatively rare phenomenon of cerebral infarction in children. The purpose of the present paper is to describe the cerebral angiographic findings in 48 children whose ischemic lesions were confirmed by CT scan. The majority of lesions were considered to be idiopathic. The areas of cerebral infarction appearing in the CT scans were located in the territory of the middle cerebral artery including the basal ganglia. Angiographical abnormalities were observed in 40 patients (83%). The majority occurred in the supraclinoid portion of the internal carotid artery and in the cisternal portion of the middle and anterior cerebral arteries. Multiple lesions, such as in the C1, A1, and M1 or the C1, M1, and M2 segments were observed in 22 cases. These lesions generally appeared in continuation; no bilateral intracranial lesions were observed. Repeated angiography was performed in 22 cases, and in 55% of these some recovery of the lesions was seen.     

Normal pressure hydrocephalus in myotonic dystrophy

Two elderly siblings with myotonic dystrophy (MD) were admitted with symptoms and signs of normal pressure hydrocephalus, the diagnosis being confirmed by CT scan and infusion test. A further 11 younger members of the family also had MD; in 2 of these, none of whom had cerebral symptoms, CT scan showed cerebral ventricular enlargement. Based on these findings, together with earlier reports on progressive cerebral ventricular enlargement in patients with MD, it is suggested that in some cases normal pressure hydrocephalus may be a late complication of MD.     

Phase-contrast cine MRI revealing en valve mechanism in spontaneous third ventriculostomy: Report of a case and literature review

A 50-year-old epileptic woman affected by hydrocephalus due to aqueductal stenosis was admitted to the hospital because of headache, dysarthria, and mild lateral pulsion. Cranial computed tomography (CT) revealed left cerebellar hemorrhage. Subsequent magnetic resonance imaging (MRI) of the brain demonstrated an enlarged ventricular system unchanged from prior studies. Flow-sensitive phase-contrast (PC) cine magnetic resonance imaging showed flow absence through the aqueduct and flow pulsations through the third ventricle floor in systole and diastole, consistent with spontaneous third ventricle patency. On stationary tissue images, the third ventricle floor and the mamillary body were displaced downward at systole and upward at diastole. Stenosis of the cerebral aqueduct of Sylvius was also shown. Retrospective evaluation of the sagittal T2-weighted images disclosed flow void at the level of the third ventricle floor. On–off movements of the third ventricle floor could account for chronic hydrocephalus persistence by an en valve mechanism. Spontaneous third ventriculostomy (STV) was diagnosed on the basis of these findings.     

A case of reversible cerebral vasoconstriction syndrome (RCVS) triggered by a Chinese herbal medicine]

A 51-year-old woman started taking Chinese medicine containing ephedara herba as a nasal decongestant. One week later, she had three episodes of thunderclap headache, one during defecation and the others while taking a bath. She then had a convulsive seizure upon resolution of the second headache. A cranial CT did not show subarachnoid hemorrhage. Repeated CSF examinations showed neither xanthochromia nor inflammation. Brain diffusion-weighted and FLAIR MR images revealed high intensity lesions in bilateral hemispheres. A cerebral angiography showed multifocal segmental stenosis of bilateral cerebral arteries. Four months later, follow-up angiography showed normalized flow in all cerebral arteries and we gave a diagnosis of reversible vasoconstriction syndrome (RCVS). She has had no symptoms and signs since the third attack of headache. RCVS is an important disease in the differential diagnosis of thunderclap headache without neurological deficit. This is the first report of RCVS triggered by Chinese herbal medicine.     

A family of hereditary communicating hydrocephalus with trigonocephaly

We studied a family of hereditary hydrocephalus with trigonocephaly, affecting eight members (four males and four females) across two generations. A proband in this family was 51 year old man, who complained of nonprogressive gait disturbance after the age of 20 years. He was admitted to our hospital because of non-neurological disease. Accidentally urinary incontinence appeared and then CT scan was performed, which revealed marked dilatation of the lateral ventricles. He was short stature and showed trigonocephalic forehead, but his head circumference was 56 cm. Mild dementia, spastic gait and hyperreflexia were observed on neurological examinations. A lumbar puncture disclosed that cerebrospinal fluid pressure was 115 mm H2O and sugar, protein and cells were normal. His skull X-ray film demonstrated temporal buldging of the calvarium, but its breadth length and height were within normal limits. Sagittal, coronal and lomboid sutures were not fused. However, skull bones were thinned and the top of dorsum sellae was erosive. A marked symmetrical dilatation of lateral, third and fourth ventricles were found in CT scan, to the contrary, bilateral Sylvian fissures and cortical sulci were slightly widened. On R.I. cisternography, ventricular reflux was noted during 3 to 72 hours after the injection. No accumulation of R. I. was observed in the parasagital region. In the arterial phase of the right carotid angiography, slight displacement was noted in Sylvian branches of bilateral middle cerebral arteries.(ABSTRACT TRUNCATED AT 250 WORDS)     

Absence of both internal carotid arteries

Summary A 63-year-old man developed a slight left hemiparesis. CT scan showed an intracerebral tumour, which was later identified as glioblastoma multiforme. Angiographic examination revealed the absence of both internal carotid arteries. Blood supply of anterior and middle cerebral arteries was provided by communication between a tortuous megadolichobasilar artery and the circle of Willis through enlarged posterior communicating arteries. The case is reported with reference to clinical symptoms as well as angiographic and anatomical findings of 17 comparable cases mentioned in literature.     

Severe Symptomatic Vasospasm following Intraventricular Hemorrhage from Arteriovenous Fistula

The authors present a rare case of severe vasospasm following the rupture of arteriovenous fistula. On initial CT scan, hematoma in the corpus callosum and left inferior frontal region with surrounding cerebromalacia and all ventricles without apparent subarachnoid hemorrhage were seen. Angiograms showed arterivenous fistula but did not show cerebral vasospasm. Thirteen days after admission the neurological state of patient suddenly deteriorated and bilateral motor weaknesses developed. Following angiograms revealed severe narrowing on the supraclinoid portion of bilateral internal carotid arteries, bilateral anterior cerebral arteries and bilateral middle cerebral arteries. Transluminal angioplasty and intra-arterial papaverine infusion were performed. The patient remained stable with moderate neurologic deficits.