Magnetic resonance imaging of colloid cysts of the third ventricle

Summary Two cases of colloid cyst of the third ventricle are reported. Their computed tomographic (CT), magnetic resonance (MR) and neuropathological features are presented. The MR findings were different in the two cases for reasons not yet fully explained, full biochemical and biophysical analyses of the cyst contents not being available. Neuropathologically, the only significant difference was the abundant presence of cholesterin crystals in the colloid of case 1 and their absence in case 2. One of our cases is also peculiar from a CT point of view, since it was primarily hypodense and did not enhance on intravenous contrast administration.     

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.     

Radiologic Manifestations of Colloid Cysts: A Pictorial Essay

Colloid cysts are among rare benign tumours of the third ventricle. Although the most frequent symptoms are headache and syncope, arrest hydrocephalus or sudden death could appear with colloid cysts. The aim of this pictorial essay was to increase awareness of the clinical presentation, computed tomography (CT) and magnetic resonance (MR) imaging spectrum, and treatment options of the colloid cysts. The data of 11 patients with histopathologically and/or clinically proven colloid cyst were analysed, retrospectively; and the neuroradiologic appearances of the cysts were evaluated. The CT and MR appearance of colloid cysts may change, depending on the viscosity or the cholesterol content of the cysts. However, the cystic content is the most important factor that could affect the success of treatment. Cysts that are especially rich in protein and cholesterol tend to be hyperdense on CT, hypointense on T2-weighted sequences and hyperintense on T1-weighted sequences. These cysts are viscous, and the success of aspiration is significantly low. In the diagnosis and evaluation of small-sized cysts that have an ingredient similar to cerebrospinal fluid, 3-dimensional sequences might be useful. The radiologic appearances of colloid cysts could play an important role in directing these patients to alternative surgical modalities, including resection.     

Colloid cysts of the third ventricle: MR findings

Magnetic resonance was performed in five patients with obstructive hydrocephalus due to surgically proven colloid cyst of the third ventricle. On T1-weighted images two lesions were homogeneously hyperintense and another homogeneously isointense with the surrounding brain parenchyma. On T2-weighted images these three lesions were strongly hypointense except for a hyperintense rim at the periphery. At surgery in these patients the cyst was thin walled and filled with viscous colloidal material. In two patients the content of the lesion was composed of two layers. The outer layer was hyperintense and the inner layer hypointense in one patient. In the other patient the periphery of the lesion was isointense with central hypointensity. On T2-weighted images the content of both lesions was hyperintense at the periphery with central hypointensity. In these last two patients at surgery the cyst was thin walled too. However, two clearly different components could be found in the cyst content: an outer component composed of amorphous material and cellular debris and an inner component consisting of viscous material.     

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.     

Meningioma of the third ventricle

Summary Meningiomas of the third ventricle are rare intracranial neoplasms. We reported such a case in a 42 years old man without clinical evidence of increased intracranial pressure. Computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated the tumour sitting in the superior and anterior part of the third ventricle, bulging into the lateral ventricles. CT was more effective than MRI in the demonstration of calcifications whereas MRI proved to be superior in delineation of the tumour and its relation with surrounding structures.     

Necrotizing fasciitis with fatal outcome: a report of two cases

Two cases of sudden and unexpected death due to necrotizing fasciitis are presented with a short overview of this rare disease with special reference to pathological features and causative and epidemiological factors. One case occurred as a complication of liposuction surgery, and the second presented after minor trauma. Based on the autopsy findings and an interdisciplinary approach, medico-legal evaluation provides a substantial basis for later court hearings in such cases.     

Black oesophagus: a rare disorder with potentially fatal outcome

Black oesophagus is a rare pathological condition of unknown aetiology characterised by a full length, circumferential black discolouration of the entire oesophageal mucosa. The disease is sporadically encountered during upper gastrointestinal endoscopy. We used conventional histology, enzyme histochemistry and immunohistology to examine five autopsy cases (four males, one female; age range 43–86 years) of black oesophagus. On microscopical examination, the esophageal mucosa was entirely necrotic with demarcation by a leukocytic infiltrate in the upper submucosa. This infiltrate was dominated by neutrophilic granulocytes and scattered macrophages lacking haemosiderin deposits, placing the noxious mucosal injury in a time frame of approximately 24–72 h prior to death. Black oesophagus was established as the immediate cause of death in one case due to desanguination from the oesophagus and significantly contributed to the fatal outcome in a second case. Apart from a history of chronic alcohol consumption in four cases, no other pre-existing pathological or debilitating conditions could be established. The remarkably consistent pathomorphological picture of the disease seems to be the result of impaired microcirculation of the oesophageal mucosa due to prolonged hypotension of variable aetiology. The diagnosis of black oesophagus requires exclusion of other causes such as ingestion of caustic materials and should be based on histological examination.     

MRI detection of ruptured malignant teratoma in the third ventricle

We describe a case in which CT and MRI showed evidence of intraventricular fat, which proved to have come from a ruptured malignant teratoma.     

A case report of lethal post-viral lymphocytic myocarditis with exclusive location in the right ventricle

The inflammatory involvement of vital organs may represent a dangerous and life-threatening situation: in particular, the inflammation of the myocardial tissue of the heart may lead to severe consequences since the clinical history of the disease may be completely asymptomatic, any clinical sign may be lacking, thus preventing correct diagnosis and treatment. This may occur even in the case of myocarditis and may lead to unexpected death whose cause can be assessable only by means of a thorough histopathological examination. The article reports the case of 61-year old female who developed a flu-like syndrome with very few symptoms, followed by sudden death in three weeks. The autopsy and following histopathological investigations identified the cause of death in a post-viral lymphocytic myocarditis, probably related to the previous infectious disease, and alternative causes (as arrhythmic ventricular dysplasia, vasculitis, sarcoidosis and giant cell myocarditis) were excluded. The exclusive location in the right ventricle was a peculiar finding. The case highlights the importance of the myocardium of the right ventricle, a tissue which is often less considered even in histopathological surveys. The exclusive location of myocarditis in the right ventricle is a rare event but in this case fully responsible for death.     

Thoracic spinal intradural arachnoid cyst: report of two cases and review of literature

We report two cases of spinal intradural arachnoid cyst at the thoracic level, presenting with long-standing symptoms of spinal cord compression and MRI findings that were overlooked for sometime initially. Because of the rarity of this disease, and because of the subtle changes on MRI, there was a definite delay in the diagnosis. In this report we emphasize the value of MRI and CT myelography in this disorder, and the need for them to be strongly correlated with the progression of the clinical picture.     

Sudden death after isobutane sniffing: a report of two forensic cases

The intentional inhalation of a volatile substance (“sniffing”) causing euphoria and hallucinations is an under-recognised form of substance abuse in children and adolescents with a high morbidity and mortality. Sudden death can be caused by cardiac arrhythmia, asphyxia or trauma. Two fatal cases of isobutane sniffing of cigarette lighter refill containing isobutane are reported. Toxicological investigations revealed the presence of isobutane in the heart blood and brain tissue of both cases (case 1: heart blood 0.1 μg/g, brain tissue 2.3 μg/g; case 2: heart blood 4.6 μg/g, brain tissue 17.4 μg/g) and the presence of its metabolite 2-methyl-2-propanol in the heart blood of both cases (0.5 and 1.8 μg/g, respectively). The histological investigations of the inner organs showed similar results in both victims. Autopsy findings, results of the histological and immunohistochemical investigations, toxicological findings and analytical procedures are discussed.     

Sudden death by laryngeal polyp: a case report and review of the literature

Sudden unexpected death in the context of bizarre or unusual behavior usually relates to acute drug intoxication or excited delirium. We report the case of a man who died suddenly while running naked on a public street. Although the initial death investigation was indicative of excited delirium or drug intoxication, autopsy revealed glottic obstruction by an inflammatory laryngeal polyp. Toxicologic studies were negative and investigation revealed presentation at a hospital the day before death with stridor. It is believed he developed airway obstruction while dressing at home and ran out on the street to find assistance. This case illustrates the importance of a thorough death investigation and a broad differential diagnosis when approaching a forensic autopsy.     

Colloid cysts of the third ventricle: correlation of MR and CT findings with histology and chemical analysis

Eight patients with colloid cysts of the third ventricle were examined with CT and MR. In six, surgical resection was performed and the material was subjected to histologic evaluation; the concentrations of trace elements were determined by particle-induced X-ray emission. Stereotaxic aspiration was performed in two. The investigation showed that colloid cysts are often iso- or hypodense relative to brain on CT (5/8), but sometimes have a center of increased density. Increased density did not correlate with increased concentration of calcium or other metals but did not correlate with high cholesterol content. Colloid cysts appear more heterogeneous on MR (6/8) than on CT (3/8), despite a homogeneous appearance at histology. High signal on short TR/TE sequences is correlated with a high cholesterol content. A marked shortening of the T2 relaxation time is often noticed in the central part of the cyst. Analysis of trace elements showed that this phenomenon is not related to the presence of metals with paramagnetic effects. Our analysis of the contents of colloid cysts does not support the theory that differing metallic concentrations are responsible for differences in MR signal intensity or CT density. We did find that increased CT density and high MR signal correlated with high cholesterol content.     

Colloid cysts of the third ventricle: correlation of MR and CT findings with histology and chemical analysis

Eight patients with colloid cysts of the third ventricle were examined with CT and MR. In six, surgical resection was performed and the material was subjected to histologic evaluation; the concentrations of trace elements were determined by particle-induced X-ray emission. Stereotaxic aspiration was performed in two. The investigation showed that colloid cysts are often iso- or hypodense relative to brain on CT (5/8), but sometimes have a center of increased density. Increased density did not correlate with increased concentration of calcium or other metals but did correlate with high cholesterol content. Colloid cysts appear more heterogeneous on MR (6/8) than on CT (3/8), despite a homogeneous appearance at histology. High signal on short TR/TE sequences is correlated with a high cholesterol content. A marked shortening of the T2 relaxation time is often noticed in the central part of the cyst. Analysis of trace elements showed that this phenomenon is not related to the presence of metals with paramagnetic effects. Our analysis of the contents of colloid cysts does not support the theory that differing metallic concentrations are responsible for differences in MR signal intensity or CT density. We did find that increased CT density and high MR signal correlated with high cholesterol content.     

Cranial aneurysmal bone cysts presenting with raised intracranial pressure: report of two cases

Aneurysmal bone cysts in the skull vault are reported in two patients 7 and 9 years old, who presented with vomiting and headaches caused by raised intracranial pressure. CT showed the cystic lesion in the diplo%e, with predominantly inward expansion. Fluid-fluid levels were seen on both CT and MRI; the latter also showed bleeding within the cyst. MR angiography showed compression of the superior sagittal sinus in the second case. Received: 29 April 1996 Accepted: 30 September 1996     

Epidermal inclusion cyst of phalanx: a case report and review of the literature

Epidermal cyst within a toe phalanx is an extremely rare condition. It is important to differentiate this benign lesion, which can be easily treated by curettage, from other benign and malignant lesions of the bone with a similar clinical presentation, and which may require amputation of the toe. This report describes one such lesion in the mid-phalanx of the fourth toe in a 48-year-old woman, and which was successfully identified by intra-operative frozen diagnosis and treated by curettage.