Hypodense colloid cyst of the third ventricle

The diagnosis of colloid cysts of the third ventricle using computed tomography (CT) rarely causes problems. The typical well-rounded, hyperdense mass in the anterior part of the third ventricle is usually well shown, along with the associated lateral ventricular dilatation. However, it is also well recognized that these cysts may be isodense, and this can on occasion lead to diagnostic difficulty. Rarely have hypodense colloid cysts been reported. We describe two patients in whom the low density of the tumors led, initially, to a failure to identify them on the CT scan. Although this is an atypical appearance, it is important to be aware of it, as colloid cysts which are surgically curable have a definite morbidity and mortality if untreated.     

Spontaneous resolution of a colloid cyst of the third ventricle

We report a case of an asymptomatic colloid cyst of the third ventricle in a 35-year-old male, which on follow-up MRI at 15 months appears to have spontaneously resolved. To our knowledge, this is the first such case reported and supports the role of conservative management of small asymptomatic colloid cysts.     

Changing characteristics of a colloid cyst of the third ventricle

We describe extremely unusual radiological characteristics in a colloid cyst of the third ventricle, where the cyst became dense and its size decreased following a cerebrospinal fluid diversion procedure. Such a course of events has been reported in colloid cysts only twice in the literature. Received: 25 June 1998 Accepted: 23 July 1998     

Magnetic resonance imaging of a colloid cyst of the third ventricle

A case of an isodense non-enhancing colloid cyst of the third ventricle which was not easily diagnosed by computed tomography is described. The patient underwent magnetic resonance imaging which clearly showed a colloid cyst of the third ventricle with accompanying obstructive hydrocephalus. Such lesions are potentially life-threatening if undiagnosed. It is suggested that magnetic resonance imaging has an important role to play in rapidly and clearly demonstrating the location, size and complications of such lesions when there is doubt about the aetiology of obstructive hydrocephalus of the lateral ventricles on computed tomography.     

Colloid cyst of the third ventricle: imaging-pathologic correlation

Colloid cysts are relatively rare intracranial lesions located in the rostral aspect of the third ventricle. They may produce acute hydrocephalus, brain herniation, and lead to death. Although the clinical and imaging features of colloid cysts are well known, their etiology and the factors responsible for their imaging features continue to be a subject of debate. We present the imaging-pathologic correlation of a patient with a colloid cyst as well as data supporting the fact that the presence of cholesterol is probably responsible for the MR imaging features exhibited by some colloid cysts.     

Change in CT radiodensity of a colloid cyst of the third ventricle: case report and literature review

A unique case is presented of a decrease in density on CT scans of a colloid cyst of the third ventricle with time. This occurred in the absence of any operative intervention in a 35-year-old woman.     

Diagnosis of ependymal intraventricular cysts of the third ventricle by computed tomography

Summary The radiological features of seven patients with surgically verified intraventricular ependymal cyst of the third ventricle are presented. In two patients the pre-operative diagnosis was made by ventriculography, in two by ventriculography and computed tomography (CT), and in the last three patients CT alone was sufficient for correct diagnosis: ventriculography was no longer necessary. The third ventricle is indistinguishable from a cyst with an oval or nearly round configuration with a width-to-length ratio varying between 0.53 and 0.91 (mean 0.79). The density of cerebrospinal fluid within the thired ventricle/cyst is a little higher than that of the lateral ventricles. A cyst can also be seen within the suprasellar cistern. The septum pellucidum is not widened, and the internal cerebral veins are pushed up between the lateral ventricles. These diagnostic signs show up well in coronal CT sections. The round third ventricle together with the rounded and enlarged frontal horns of the lateral ventricles often give an impression of the head of Mickey Mouse.     

Colloid cyst of the third ventricle: sometimes more conspicuous on CT than MR.

We present two cases of surgically proved colloid cysts that were more apparent on CT scans than on MR images. These cysts, while hyperdense on CT scans, were nearly isointense with brain on multiple MR sequences. This relative lack of visibility represents a potential pitfall when imaging a patient with headache.     

椎管内肠源性囊肿1例

患者男,27岁。因颈部疼痛7年,加重伴四肢麻木无力4天,自末端向中心发展,弯腰时加重入院。查体:四肢感觉减退,左侧著,左侧肢体肌力IV级,右侧肢体肌力IV+级、肌张力偏高,双侧膝腱反射、跟腱反射亢进,Babinski征(+),Chaddock征(+)。MRI表现:颈3~5水平椎管内脊髓腹侧偏左髓外硬膜下可见一条形长T1长T2信号影,病灶内信号均匀,边界清晰,     

Rupture of a cyst during compression at mammography. Report of a case

The pressure at dedicated mammographic units, indicated by a manometer, shows the pressure in the hydraulic system. The reading of this instrument is misleading because the pressure in the breast caused by the compression plate is considerably lower. Appropriate compression during mammographic examination may, however, rupture cysts.