Migrating intraventricular cysticercosis: magnetic resonance imaging findings

Refractory Immune-Mediated Cysticercal Meningitis and Role of B Cell Depleting Therapy

BACKGROUND

Extraparenchymal neurocysticercosis (NCC) commonly presents with symptoms of raised intracranial pressure such as headache, nausea, vomiting, or delirium. Intraventricular NCC is frequently associated with obstructive hydrocephalus as well as recurrent inflammatory cascade leading to chronic meningitis.

OBJECTIVE

The aim of this study was to report the novel use and benefit of B cell depleting therapy in a case of treatment-refractory cysticercal meningoencephalitis.

CASE

In this article, we report about a young male with intraventricular NCC, who had recurrent meningitis (with encephalitis) and kept relapsing despite multiple cerebrospinal fluid diversion procedures, cysticidal therapy, and high-dose steroids. He finally showed clinical and radiological resolution with pulsed rituximab therapy.

CONCLUSION

This off-label use of a monoclonal antibody against CD20 may be considered as a rescue therapy in steroid-refractory immune-mediated cysticercal meningitis.

Is Antihelminthics Necessary in Postoperative Treatment of Intraventricular Neurocysticercosis? A Systematic Review

OBJECTIVE

Patients with intraventricular neurocysticercosis (IVNCC) may require cerebrospinal fluid diversion surgery for late-onset hydrocephalus in the postsurgical period. Controversy exists regarding cysticidal treatment. Our main objective was to compare surgically treated cases of IVNCC that received postoperative anthelmintics with those that did not regard the incidence and treatment of late-onset hydrocephalus.

METHODS

We searched the Medline database and extracted the following data: age, gender, stage of development of cysticercosis, type of operation, frequency of delayed hydrocephalus, cerebrospinal fluid diversion surgery, outcome, and follow-up.

RESULTS

We analyzed 130 articles on intraventricular cysticercosis and identified 117 cases of isolated IVNCC and 314 patients in the case-control series who met inclusion criteria. There was no significant difference in postoperative delayed hydrocephalus between isolated IVNCC and case-control study groups. Children under the age of 16 received anthelmintic drugs more frequently during the postoperative period. Statistical relevance was observed in all patient groups regarding the application of steroids in favor of cysticidal therapy Endoscopy was a better option than craniotomy for cases of isolated IVNCC and case-control studies. Other variables were not relevant.

CONCLUSIONS

Patients who received antihelminths did not show a statistically significant reduction in delayed hydrocephalus compared to individuals who did not receive after surgical resection of the parasite. Corticosteroid therapy prevailed in people who have been treated with anthelmintics. Children under the age of 16 were administered anthelmintic drugs more frequently during the postoperative period. Endoscopy was the preferred method for all groups, but some patients with cysts in the fourth ventricle required a craniotomy.

Stereotactic surgery for neurocysticercosis of the 4th ventricle: illustrative cases

BACKGROUND

Neurocysticercosis, caused by the larval stage of Taenia solium, affects the cerebral ventricles in 20–30% of cases and may lead to hydrocephalus and other neurological morbidity. Conventional treatment for cysts in the 4th ventricle includes open surgery (suboccipital approach) and neuroendoscopy, with the latter being the option of choice. Stereotactic surgery, minimally invasive, offers a good alternative for this type of deep lesion.

OBSERVATIONS

The authors report the cases of two women, 30 and 45 years old, who presented with headache, dizziness, and ataxia and were diagnosed with 4th ventricle cysticercosis. Magnetic resonance imaging (MRI) revealed dilated 4th ventricles (approximately 2.5 cm in both cases, with cystic images inside the ventricular cavity). Both patients were treated with stereotactic surgery via a suboccipital transcerebellar approach. Cyst material was extracted, and the diagnosis was confirmed by pathological examination. The surgeries had no complications and resulted in clinical improvement. Control MRI scans showed reduction of the volume of the ventricle without residual cysts.

LESSONS

Minimally invasive stereotactic surgery provided a safe alternative for 4th ventricle neurocysticercosis cysts, with more benefits than risks in comparison with conventional techniques.

The rolling cyst: migrating intraventricular neurocysticercosis-a case-based update

BACKGROUND

Neurocysticercosis is the most frequent parasitic disease of the central nervous system, and its incidence in the developed countries is increasing due to immigration and travels from endemic areas. The intraventricular location has been found to involve up to 61.3% of the patients; moreover, only 22 cases of migrating intraventricular cyst have been reported so far. Despite the rarity of the condition in western countries, its occurrence generates some concerns and the aim of this paper is to update the information concerning pathogenesis, clinical presentation, diagnosis and management of this entity.

METHODS AND RESULTS

All the pertinent literature was analysed, focused on the cases of migrating intraventricular neurocysticercosis and its peculiar features. An illustrative case regarding a 14-year-old girl is also presented.

CONCLUSIONS

Migrating intraventricular neurocysticercosis is a pathognomonic entity usually presenting with hydrocephalus, and its treatment is mainly surgical, preferring an endoscopic approach. When the resection of the intraventricular cyst is not performed, an accurate follow-up is mandatory to detect clinical changes due to a recurrent hydrocephalus or to the effect of the dying cyst on the surrounding area. In case of permanent shunt placement, the cysticidal and steroid treatment is recommended to reduce the risk of shunt failure.

Fourth ventricle neurocysticercosis: A case report

Background:

Neurocysticercosis (NCC) is the most common helminthic disease of the nervous system in humans and it is caused by the larvae of the pork tapeworm, Taenia solium. We present a case of microsurgical removal of a fourth ventricle NCC cyst combined with an endoscopic third ventriculostomy (ETV) to treat hydrocephalus.

Case Description:

A 36-year-old woman presented to the emergency room with headache and decreased visual acuity over the last 4 months. A brain magnetic resonance imaging showed obstructive hydrocephalus apparently correlated to a mobile, cystic lesion of the fourth ventricle. In the same operative time, an ETV and a suboccipital craniotomy were performed in order to remove the lesion and to treat the hydrocephalus. The cyst was completely removed and pathologically identified as a T. solium cyst. The early postoperative course was uneventful and she was discharged asymptomatic and off anthelmintic medication. Five weeks later, the patient returned with hydrocephalus recurrence and was successfully retreated with an ETV. At 5-month follow-up, she remains asymptomatic and has no evidence of persistent disease or hydrocephalus recurrence.

Conclusion:

Intraventricular neurocysticercosis is, typically, a surgical disease. For cysts located on the fourth ventricle, a suboccipital craniotomy and a telovelar approach remains a valid option. Cyst removal does not necessarily resolve the hydrocephalus problem. ETV offers an option to the classic shunt placement approach and was shown to be effective even on hydrocephalus recurrence.

Intraventricular migration of an isolated fourth ventricular cysticercus following cerebrospinal fluid shunting

BACKGROUND

Isolated intraventricular neurocysticercosis (NCC) is less frequently seen and can be missed on plain magnetic resonance imaging (MRI). Three-dimensional constructive interference in steady state (CISS) sequence is an extremely helpful sequence in identifying the lesion but is rarely used routinely.

CASE DESCRIPTION

Here, we report a case of young male adult who presented with diminution of vision and headache. MRI of the brain revealed hydrocephalus, and on using CISS sequence only, the lesion could be identified in the fourth ventricle. He was treated with medical management, and ventriculoperitoneal shunting of cerebrospinal fluid was done to relieve the hydrocephalus. It resulted in immediate relief with aggravation of headache few days later. Repeat MRI revealed intraventricular migration into the left foramen of monro leading to left lateral ventricle dilatation necessitating endoscopic removal of the lesion.

CONCLUSION

CISS sequence is definitely the sequence of choice in identifying intraventricular NCC. Ventriculoperitoneal shunting can result in the intraventricular migration of the cyst due to sudden decompression necessitating repeat surgery. Endoscopic removal of NCC has a high success rate with limited complications.

Revised diagnostic criteria for neurocysticercosis

BACKGROUND

A unified set of criteria for neurocysticercosis (NCC) has helped to standardize its diagnosis in different settings.

METHODS

Cysticercosis experts were convened to update current diagnostic criteria for NCC according to two principles: neuroimaging studies are essential for diagnosis, and all other information provides indirect evidence favoring the diagnosis. Recent diagnostic advances were incorporated to this revised set.

RESULTS

This revised set is structured in absolute, neuroimaging and clinical/exposure criteria. Absolute criteria include: histological confirmation of parasites, evidence of subretinal cysts, and demonstration of the scolex within a cyst. Neuroimaging criteria are categorized as major (cystic lesions without scolex, enhancing lesions, multilobulated cysts, and calcifications), confirmative (resolution of cysts after cysticidal drug therapy, spontaneous resolution of single enhancing lesions, and migrating ventricular cysts on sequential neuroimaging studies) and minor (hydrocephalus and leptomeningeal enhancement). Clinical/exposure criteria include: detection of anticysticercal antibodies or cysticercal antigens by well-standardized tests, systemic cysticercosis, evidence of a household Taenia carrier, suggestive clinical manifestations, and residency in endemic areas. Besides patients having absolute criteria, definitive diagnosis can be made in those having two major neuroimaging criteria (or one major plus one confirmative criteria) plus exposure. For patients presenting with one major and one minor neuroimaging criteria plus exposure, definitive diagnosis of NCC requires the exclusion of confounding pathologies. Probable diagnosis is reserved for individuals presenting with one neuroimaging criteria plus strong evidence of exposure.

CONCLUSIONS

This revised set of diagnostic criteria provides simpler definitions and may facilitate its more uniform and widespread applicability in different scenarios.

Migration of intraventricular neurocysticercus after ventriculostomy

Intraventricular neurocysticerci are an uncommon occurrence and are often difficult to diagnose. They are often a cause of obstructive hydrocephalus and inflammatory reactions, which can be life threatening. Intraventricular neurocysticerci are most common in the fourth ventricle and surgical decompression of obstructive hydrocephalus is an important step in their management. However, these cysticerci are also known to migrate within the ventricular system and may cause confusion during surgery. It thus becomes very important for radiologists and neurosurgeons to be aware of this phenomenon.

Experimental encephalitis caused by Taenia crassiceps cysticerci in mice

OBJECTIVES

To present the experimental model of neurocysticercosis (NCC) caused by Taenia crassiceps cysticerci, to describe the inflammatory process, susceptibility, or resistance of BALB/c and C57BL/6 mice to this infection, and to describe the host-parasite relationship.

METHODS

The animals were intracranially inoculated with initial stage T. crassiceps cysticerci. They were euthanized at 7, 30, 60, and 90 days after the inoculation. Their encephala were removed for the histopathologic analysis, classification of the parasites, and inflammatory lesions.

RESULTS

Experimental NCC was observed on both mice lineages. BALB/c mice presented inflammatory lesions with greater intensity, inducing necrosis on late stage parasites, and with an acute inflammation pattern, while C57BL/6 mice showed greater capability on provoking early necrosis in the cysticerci, which showed a chronic inflammation pattern.

CONCLUSIONS

This experimental model induced NCC on mice with characteristic inflammation and lesions. C57BL/6 mice were able to induce precocious necrosis of the parasites presenting inflammatory lesions with lower intensity.

Parasitic diseases of the central nervous system

This article reviews the characteristic imaging appearances of parasitic diseases of the central nervous system, including cysticercosis, toxoplasmosis, cystic echinococcosis, schistosomiasis, amebiasis, malariasis, sparganosis, paragonimiasis, and American and African trypanosomiases. Routine precontrast and postcontrast MR imaging helps in localization, characterization, delineation of extension, and follow-up of the parasitic lesions. Moreover, recently developed tools, such as diffusion, perfusion, and MR spectroscopy, help to differentiate parasitic diseases of the central nervous system from simulating lesions. Combining imaging findings with geographic prevalence, clinical history, and serologic tests is required for diagnosis of parasitic diseases of the central nervous system.

CT Ventriculography for diagnosis of occult ventricular cysticerci

Background:

Neurocysticercosis is the most common parasitic infection of the central nervous system (CNS). Intraventricular lesions are seen in 7–20% of CNS cysticercosis. Intraventricular lesions can be missed by computed tomography (CT) and magnetic resonance imaging (MRI) as they are typically isodense/isointense to the cerebrospinal fluid. We present our experience with CT ventriculography to visualize occult cysts.

Case Description:

Two patients presented with hydrocephalus and suspected neurocysticercosis were evaluated with CT and MRI with and without contrast failing to reveal intraventricular lesions. CT-ventriculography was used: 10 ml of cerebrospinal fluid was drained from the ventriculostomy catheter, and 10 ml of iohexol 240 diluted 1:1 with preservative-free saline was injected through the ventriculostomy catheter. Immediate CT of the brain was performed. The first patient had multiple cysts located throughout the body of the left lateral ventricle. The second patient had a single lesion located in the body of the lateral ventricle. The CT-ventriculography findings helped in identifying the lesions and plan the surgical intervention that was performed with the aid of an endoscope to remove the cysts.

Conclusions:

Intraventricular neurocysticercosis is a common parasitic disease which can be difficult to diagnose. We used CT-ventriculography with injection of contrast through the ventriculostomy catheter in two patients where CT and MRI failed to demonstrate the lesions. This technique is a safe and useful tool in the imaging armamentarium when intraventricular cystic lesions are suspected.