An intraventricular arachnoid cyst

Symptomatic intraventricular choroid plexus cysts. Illustrative case and systematic review

Although choroid plexus cysts are a frequent incidental neuroimaging finding, symptomatic ones are rare-a series of more than five cases are hard to find. In the absence of high-volume studies, there are no generally accepted algorithms for diagnosis and treatment for this pathology. Proposed surgical techniques include microsurgical excision or fenestration and endoscopic excision or fenestration with or without additional shunting. No definitive conclusions exist about the superiority of a certain technique. Here, we introduce an illustrative case of a patient with a symptomatic choroid plexus cyst in the trigone of the lateral ventricle and a systematic review of 65 additional published cases with the aim of identifying epidemiological features, variants of localization of the cysts, their symptoms, persistence of concomitant obstructive hydrocephalus, and treatment modalities. A PRISMA-based literature search was performed on the PubMed, MEDLINE, Scopus, and Web of Knowledge databases. We include in the review case reports and case series of symptomatic choroid plexus cysts with full texts or valuable abstracts available online in English and published by April 2023. All abstracts of retrieved studies were assessed by two independent researchers to avoid bias. Only descriptive statistics were used for the presentation of the results. A total of 48 studies (39 case reports and 9 case series) with 65 depicted cases met the eligibility criteria. The review showed a slight predominance of choroid plexus cysts in men. The most common localizations of cysts were the trigone and the body of the lateral ventricle. Obstructive hydrocephalus is often present in patients with choroid plexus cysts. The most common symptoms of cysts were signs of increased ICP: headaches and vomiting. The main treatment approaches for symptomatic choroid plexus cysts were microsurgical excision, microsurgical fenestration, endoscopic fenestration, and total endoscopic excision. The tendency has been noted to shift from microsurgical to endoscopic procedures over the past two decades. Some data on the classification of cysts of the central nervous system and the underlying mechanisms of the pathogenesis of choroid plexus cysts are also presented.Although symptomatic cases of choroid plexus cysts are rare, by summarizing currently available data, one could clarify their common features and identify a preferable treatment modality.

Arachnoid cyst of the velum interpositum originating from tela choroidea

BACKGROUND

Arachnoid cysts originating from the velum interpositum are very rare, and their existence as a clinicopathologic entity remains controversial. We report a case of a patient with an arachnoid cyst of the velum interpositum presenting with memory disturbance, focusing on the anatomical origin of the lesion and the physiological mechanisms causing memory disturbance.

CASE DESCRIPTION

A 65-year-old man with a large cystic lesion in the velum interpositum experienced progressive memory disturbance and enlargement of the lesion 6 months before referral to our institution. Neuropsychological evaluation on admission demonstrated severe memory disturbance. Radiological examination did not reveal hydrocephalus, but the bilateral fornices and thalami were compressed by the cyst. The patient underwent endoscopic cystoventriculostomy via the frontal horn of the right lateral ventricle through a frontal burr hole. Histopathology of the sample was consistent with that of an arachnoid cyst, and the endoscopic findings suggested that the cyst originated from the tela choroidea, which covers the velum interpositum. The symptoms resolved after surgery with significant improvement in neuropsychological test scores.

CONCLUSION

Arachnoid cysts of the velum interpositum are rare but distinct clinicopathologic entities that originate from the tela choroidea. The lesions can cause memory disturbance without hydrocephalus due to compression of the fornices and thalami, but this can be reversed by surgery.

Posttraumatic intraventricular arachnoid cyst accompanied by pseudomeningoencephalocele in a child

Growing skull fracture (GSF) is a rare complication of head trauma. A posttraumatic intraventricular arachnoid cyst (AC), neither isolated nor accompanied by a GSF has not been reported previously. A seven-year-old girl was admitted after a severe head injury with a separated right parieto-occipital fracture and contusion. She responded well to conservative therapy. Seven weeks after discharge, she was re-admitted with a large parieto-occipital pseudomeningoencephalocele due to herniation of cerebrospinal fluid and neural tissue to the subgaleal space through the widened fracture defect, an extra-axial cyst at the posterior interhemispheric space and an intraventricular cystic mass. She underwent open surgery, and the intraventricular cystic mass was totally removed. The histological findings were consistent with an AC. One week after dural repair, hydrocephalus developed, and a ventriculo-peritoneal shunt was inserted. She did well during two-year follow-up. The present case is unique as an intraventricular AC following head trauma. When an intraventricular cystic lesion is encountered after severe head trauma, the possibility of an AC should be considered; especially with neighboring contused neural tissue and leptomeningeal cyst formation.

A large arachnoid cyst of the lateral ventricle extending from the supracerebellar cistern--case report

BACKGROUND

The pathogenetic mechanism of intraventricular arachnoid cyst development is still controversial, but is believed to originate from the vascular mesenchyme or as an extension of the arachnoid cyst in the subarachnoid space into the ventricle through the choroidal fissure. We report a case supporting the extension hypothesis and suggest differential points between an intraventricular arachnoid cyst that extended from the supracerebellar space and a lateral ventricular diverticulum that extended into the supracerebellar cistern.

CASE DESCRIPTION

A 12-month-old girl presented with macrocephaly and developmental delay. Her magnetic resonance imaging showed an arachnoid cyst that had developed from the supracerebellar space in the posterior fossa, and which extended into the left lateral ventricle resulting in expansion of the left lateral ventricle and displacing the choroids plexus anteriorly and laterally and the midline to the right. We treated an intraventricular arachnoid cyst by endoscopic fenestration resulting in dramatic reduction of the intraventricular arachnoid cyst with large bilateral subdural fluid collection. We performed a subduroperitoneal shunt for subdural fluid collection and subsequent cystoperitoneal shunt for the remnant cyst.

CONCLUSION

We suggest that this case supports the extension hypothesis from the subarachnoid space through the choroidal fissure into the lateral ventricle. We also suggest that one of the radiological differential points between an intraventricular arachnoid cyst and a ventricular diverticulum is displacement and compression of the choroid plexus of the lateral ventricle.

Intraventricular congenital lesions and colloid cysts

Intraventricular congenital lesions and colloid cysts comprise a rather large spectrum of different pathologic conditions. In most cases, treatment in not warranted unless there is progressive ventricular obstruction with hydrocephalus or growth of the lesion itself, making tissue biopsy and histopathologic diagnosis necessary. Accordingly, a precise neuroradiologic evaluation is of the utmost importance, because most lesions, if not symptomatic, only require clinical and radiologic follow-up.

Arachnoid cyst of the lateral ventricle

BACKGROUND

Arachnoid cysts rarely occur within the lateral ventricles, with only 10 reported cases in the literature. They may arise from the arachnoid layer that is present in the choroidal fissure.

CASE DESCRIPTION

This 25-year-old man with headache and a left jacksonian seizure had an intraventricular arachnoid cyst of the right occipital horn and trigone found on radiologic examination by computed tomography (CT) and magnetic resonance imaging (MRI). He was successfully treated by evacuation of the cyst and removal of its wall through a right parietooccipital craniotomy. Histologic studies of the cyst wall confirmed the presence of arachnoid cells and connective tissue.

CONCLUSIONS

Arachnoid cysts of the lateral ventricles occur in the occipital horns and trigone (all but 1 of 10 cases) in young patients with symptoms of intracranial hypertension. MRI well defines the relationship of the cyst with the ventricular wall. Surgical removal of the cyst wall or cystoperitoneal shunt have been successfully performed in the reported cases; however, endoscopic fenestration of the cyst must be considered today as the treatment of choice.

Arachnoid cyst of the lateral ventricle manifesting positional psychosis

A 30-year-old woman had an arachnoid cyst in the trigone of the right lateral ventricle 5 years before she developed episodic auditory and visual hallucinations as well as delusions of persecution. The psychotic episodes tended to occur after the patient had lain in bed for 1 to 2 hours. After craniotomy and wide excision of the cystic membrane, draining the cystic fluid to the lateral ventricle, the psychotic episodes subsided in a follow-up period of 6 months. We believe that when the patient was recumbent, the trigone cyst blocked the temporal horn further, caused local ischemia, and triggered the psychosis, which was a form of partial complex psychomotor seizure.

MRI of hemorrhagic choroid plexus cyst

An unusual case of hemorrhage within a cyst in the choroid plexus of the lateral ventricle is presented. Choroid plexus cysts are commonly found incidentally on imaging studies, particularly MRI, where their characteristic appearance produces little diagnostic difficulty. In this case, high signal intensity of the cyst contents on T1-weighted images and apparent hemosiderin deposition in the cyst wall, not previously described, represented a dramatic change from a study 10 weeks previously and allowed a presumptive diagnosis of hemorrhage into the cyst, a presumption further supported by the changes in signal 20 weeks later.

Congenital arachnoid cyst of the lateral ventricles in children

The authors report a series of three children with symptomatic congenital arachnoid cyst of the lateral ventricles. Presenting symptoms consisted of macrocephally, delay in psychomotor development, and seizures. CT findings were of a well-defined cystic lesion placed in the atrium of the lateral ventricle. One child was treated by direct cyst exposure and cysto-peritoneal shunt. The other two were treated with ventriculo-cysto-peritoneal shunts; in one of these, we used a ventriculoscope both for cyst fenestration and for accurate shunt placement. The origin of intraventricular arachnoid cysts seems to be secondary to the displacement of arachnoid cells by the vascular mesenchyma, through the choroid fissure, during the process of choroid plexus development.

Neuroepithelial cyst of the lateral ventricle. Clinical features and treatment

This report concerns eight patients with noncolloid neuroepithelial cyst of the lateral ventricle, including four surgical and four conservative cases. Of the surgical patients, two had headache, one had orbital pain, and one had seizures. In the conservative group there were no symptoms due to the cysts and no changes in computed tomography scan during follow-up for an average of 1.4 years. Magnetic resonance imaging was performed in five cases and showed a cyst with an intensity similar to cerebrospinal fluid, while a cyst membrane was also detected in three cases. Our findings suggest that (1) the majority of symptomatic neuroepithelial cysts in the lateral ventricle are located in the trigone; (2) the cause of symptoms suggestive of obstruction, such as headache, is an isolated ventricle that demonstrates dilatation of the inferior horn on computed tomography and magnetic resonance imaging; (3) the operative indication is obstructive symptoms; and (4) cyst-peritoneal shunt is an effective procedure.

Primary intracranial arachnoidal cysts. A study of 67 childhood cases

Sixty-seven cases (41 males and 26 females) of arachnoidal cysts in children under 11 years are reported. About 53% of cases were diagnosed before 1 year of life. Thirty-one (42.2%) were supratentorial (interhemispheric 9, temporal fossa 10, convexity 5, sylvian fissure 3, supra- and/or retrosellar 4); 31 (46.2%) infratentorial (supra- and/or retrocerebellar 22, foramen of Magendie 3, quadrigeminal cistern 5, pontocerebellar 1); 5 (7.5%) supra- and infratentorial. Macrocephaly was the presenting symptom in 48 cases (71.5%). Associated features were frequent: cranial asymmetry in 24; aqueductal stenosis in 10; agenesis of corpus callosum in 8; deficient cerebellar lobullation in 4; Chiari I malformation in 2; neurofibromatosis type 1 with dysgenetic zones of the brain in 1; arteriovenous malformation in 1. Diagnosis was made at autopsy in six cases in the days before computed tomography and magnetic resonance: three patients had a cyst in the supra- and retrocerebellar midline; two had a cyst in the quadrigeminal cistern and the sixth was a rare case with the cyst passing from the posterior fossa to the left lateral ventricle through a hole in the basal surface of the brain. Small and some middle-sized cysts were not treated. Big and some middle-sized cysts were usually treated by cysto- and/or ventriculoperitoneal shunts. Arachnoidal cysts of the quadrigeminal cistern usually present with aqueductal stenosis and have to be treated with ventriculoperitoneal shunt. Craniotomy and fenestration of the cysts were performed in some cases with good results. The average mental level of these children is usually moderately low.

Intraventricular choroid plexus "arachnoid" cyst. MRI findings

A young women presented with chronic headaches associated with a cyst of the right lateral ventricle. The diagnosis of intraventricular so-called "arachnoid" cyst was supported by CT scan, MRI and stereotactic puncture. MRI was of great value for demonstrating that the cyst was located within the lateral ventricule, that it was delineated by a thin wall adherent to the choroid plexus and that the cyst content was CSF-like.

A case of intraventricular arachnoid cyst. How should it be treated?

A rare case of arachnoid cyst in the trigone of a lateral ventricle is reported. The patient was an 8-year-old boy who had had four episodes of convulsions prior to admission. Computed tomography (CT) and magnetic resonance imaging (MRI) demonstrated a cystic lesion containing fluid resembling cerebrospinal fluid. Although he received a cyst-peritoneal shunt, the lesion did not decrease in size. Direct removal of the cyst was then scheduled. The entire cyst was finally removed, although it was firmly attached to the choroid plexus. The enlarged trigone gradually decreased in postoperative CT. The effectiveness of a cyst-peritoneal shunt is not always satisfactory. We recommend total resection of the cyst without use of a shunt system.

Large asymptomatic noncolloid neuroepithelial cysts in the lateral ventricle: CT and MR features

Two cases of large asymptomatic cysts of the lateral ventricle are presented. The cyst walls or cyst contours were demonstrated well by proton density-weighted or T2-weighted spin echo images. These cysts are being detected as incidental findings in increasing frequency with the increasing use of MR imaging. Our data and review of the literature suggest that surgical intervention is not necessarily warranted, but that careful clinical evaluation is indicated. The diagnostic problem of intraventricular cysts is also discussed.

Noncolloid neuroepithelial cysts in the lateral ventricle: magnetic resonance features

Two patients with presumed intraventricular neuroepithelial cysts are reported. Their characteristic features on magnetic resonance imaging are described, and the importance of demonstrating the cysts' walls is underscored.

Intraventricular arachnoid cyst. Report of two cases

Two patients with intraventricular arachnoid cysts are reported and a brief review of the relevant literature is presented. Arachnoid cysts are usually extracerebral or extraventricular. Intraventricular arachnoid cysts are rare: including the two cases reported here, only five cases have been described. The following characteristics were noted in these five patients: all were young; headache was the initial symptom in four; the cyst was in the trigone of a lateral ventricle in four; and there was dilatation of the inferior horn in three.

Surgical considerations in treatment of intraventricular cysticercosis. An analysis of 45 cases

Infestations of the human brain with the larval stage of Taenia solium, once an infrequent diagnosis in the United States, is now a more frequently encountered clinical entity especially in population centers with high immigrant flux. During a recent 5-year period 45 cases of intraventricular cysticerosis have been evaluated and treated. Modes of involvement included isolated cyst formation, ependymitis, or combinations of both. Evidence of associated parenchymatous involvement was present in 20% of cases. Sites of infestation included the lateral ventricle (five cases), third ventricle (12 cases), Sylvian aqueduct (four cases), and fourth ventricle (24 cases). Mean post-therapy follow-up periods for this series exceed 36 months. This experience indicates that direct excision is the treatment of choice for ventricular cystic lesions, but that management, operative planning, and expectations should be influenced by considerations of: 1) the potential for acute clinical deterioration (38%); 2) the potential for cyst migration; 3) attendant ependymitis, defined by computerized tomography or verified at surgery; 4) the potential for increase in cyst volume with local mass effect; 5) selection and institution of corridors of surgical access that establish alternative routes of cerebrospinal fluid flow; and 6) the possibility of cyst excision by a stereotaxic endoscopic procedure.

Choroid plexus cyst in the lateral ventricle causing obstructive symptoms in an adult

This case of a rare symptomatic choroid plexus cyst in the lateral ventricle, which presented with papilledema and decreased vision, is the first such lesion found in an adult. Five earlier reported cases, all in children, are discussed, as are the limitations of computerized tomographic (CT) scanning and the need for further radiological studies to establish the diagnosis preoperatively. Metrizamide ventriculography with CT scanning is used to define the lesion and plan an operative approach.