Acute asymmetric upper nasal quandrantanopsia caused by a chiasmal colloid cyst in a patient with multiple sclerosis and bilateral retrobulbar neuritis

Diagnostic Methods in Forensic Pathology: Autoptic Findings and Immunohistochemical Study in Cases of Sudden Death Due to a Colloid Cyst of the Third Ventricle

The colloid cyst is a non-malignant tumor growth made of a gelatinous material covered by a membrane of epithelial tissue. It is usually located posterior to the foramen of Monro, in the anterior aspect of the third ventricle of the brain. Due to its location, it can cause obstructive hydrocephalus, increased intracranial pressure, and sudden cardiac death, catecholamine-mediated, through hypothalamus compression. All the mechanisms are still controversial, but the role of catecholamine has been confirmed with histological findings that highlighted myocardial injury (coagulative myocytolysis and contraction band necrosis, CBN). This study presents a case of sudden death in a previously healthy 22-year-old male due to a colloid cyst of the third ventricle. A complete autopsy was performed, highlighting in the brain an abundant quantity of cerebrospinal fluid (CSF) and a 2 cm pale grayish-green rounded cyst formation partially filling and distending the third ventricle. The diagnosis was confirmed through immunohistochemical investigation: positivity for Periodic acid-Schiff (PAS) staining and CK7 expression. In cases such as the one reported here, a combined approach of autopsy, histology, and immunohistochemistry is mandatory in order to identify the neoformation's location and morpho-structural characteristics for a correct differential diagnosis, as well as to identify the cause of death.

A unique finding of cavum velum interpositum colloid-like cyst and literature review of a commonplace lesion in an uncommon place

Colloid cysts typically reside within the area of the anterior third ventricle, in the proximity of the foramen of Monro. Although they are considered to commonly localize in various parts of the cerebrum, they are exceedingly rare outside the ventricular system and rarely occur within the velum interpositum. We have reported here a rare case of a velum interpositum colloid-like cyst in a 23-year-old man, who presented to our clinic with temporary binocular strabismus, which he had been experiencing for the previous year. In addition, we have briefly reviewed evidence regarding the generation, anatomy, and pathogenesis of colloid cysts, as well as the management options for such rare cases. The present report is only the third to describe a colloid-like cyst located within the velum interpositum, providing additional data that may aid in elucidating the pathogenesis of these neoplasms.

Olfactory colloid cyst: case report and review of extraventricular colloid cyst literature

OBJECTIVE

A rare case of an extraventricular colloid cyst located in the olfactory groove extending downward into the ethmoid sinus is presented. This is the second reported case in the world literature.

METHODS

A 56-year-old-woman presented with a lesion that was causing hyposmia and cerebrospinal fluid rhinorrhea. The lesion was an extraventricular colloid cyst displacing the left olfactory nerve downward and eroding into the left ethmoid sinus.

RESULTS

The lesion was excised, and the anterior skull base was reconstructed successfully via a unilateral subfrontal approach.

CONCLUSIONS

There were no complications, and the patient made a full recovery, with resolution of the cerebrospinal fluid rhinorrhea.