MRI of intraventricular cysticercosis: surgical implications

Added value of 3D-DRIVE and SWI Magnetic Resonance Imaging Sequences in Intraventricular Neurocysticercosis (IVNCC): An Institutional Experience from Northeast India

Background:

Prompt diagnosis and early treatment institution are important in intraventricular neurocysticercosis (IVNCC) as compared to the parenchymal or racemose form because it is associated with a poorer patient prognosis. Intraventricular neurocysticercosis is often missed on CT scan or conventional cranial magnetic resonance imaging because of similar density or signal intensity of cysticercus lesion with cerebrospinal fluid.Thestudy aims to evaluate the added value of 3D-DRIVE and SWI MRI sequences in isolated intraventricular cysticercosis with acute neurological presentation.

Methods and Materials:

This retrospective study was carried out on diagnosed 10 patients with isolated intraventricular neurocysticercosis (IVNCC) presented to a tertiary care hospital with an acute onset of symptoms or acute neurological deficit between June 2019 to May 2021. Relevant neurological examination, CSF analysis, a serological test of neurocysticercosis and MRI scan of the brain were performed.

Result:

Tenpatients of isolated intraventricular neurocysticercosis (3 males and 7 females) having 3 pediatric and 7 adults were included in this study sample.The common neurological complications of the isolated intraventricular neurocysticercosis in this study are observed as obstructive hydrocephalus in 8(80%) patients and ependymitis in 7(70%) patients. IVNCC with distinctly visualized scolex (visibility score 2) identified in 2(20%) patients in T2WI, 8 (80%) patients in 3D-DRIVE and 3(30%) patients in SWI sequences. The cyst wall of IVNCC was distinctly visualized (visibility score 2) in 1(10%) patient in T2WI, 8(80%) patients in 3D-DRIVE and 6(60%) patients in SWI sequence.

Conclusion:

Heavily T2-weighted steady-state and SWI sequences should be added to routine MRI sequences that helps to identify IVNCC and should be used in patients with unexplained hydrocephalus, especially in endemic regions of Neurocysticercosis.

Psychiatric Disorders of Neurocysticercosis: Narrative Review

Neurocysticercosis, the most common type of neuroparasitosis, is a condition in which the central nervous system (CNS) is infested with the pork tapeworm Taenia solium cysticercosis' larvae. Neurocysticercosis is the most widespread parasitic CNS disease worldwide, affecting more than 50 million individuals. As neurocysticercosis is prevalent in developing countries, the growing number of migrants and travelers increases prevalence in developed countries. Possible neuropsychiatric manifestations are depression, cognitive dysfunction, dementia, and visual hallucinations. Depending on the cysts' location in the CNS, focal neurology or psychiatric symptoms manifest. The diagnosis of neurocysticercosis is based on neuroimaging and serology. The correlation between specific symptoms and the cyst's location might help better understand psychiatric disorders' pathophysiology. Nonetheless, the exact prevalence of neurocysticercosis is seldom reported in patients with psychiatric disorders, which may be due to the lack of imaging availability in developing countries with a high prevalence.

Cellular immune response in intraventricular experimental neurocysticercosis

Neurocysticercosis (NCC) is considered a neglected parasitic infection of the human central nervous system. Its pathogenesis is due to the host immune response, stage of evolution and location of the parasite. The aim of this study was to evaluate thein situand systemic immune response through cytokines dosage (IL-4, IL-10, IL-17 and IFN-γ) as well as the local inflammatory response of the experimental NCC withTaenia crassiceps. Thein situand systemic cellular and inflammatory immune response were evaluated through the cytokines quantification at 7, 30, 60 and 90 days after inoculation and histopathological analysis. All cysticerci were found within the cerebral ventricles. There was a discrete intensity of inflammatory cells of mixed immune profile, polymorphonuclear and mononuclear cells, at the beginning of the infection and predominance of mononuclear cells at the end. The systemic immune response showed a significant increase in all the analysed cytokines and predominance of the Th2 immune profile cytokines at the end of the infection. These results indicate that the location of the cysticerci may lead to ventriculomegaly. The acute phase of the infection showed a mixed Th1/Th17 profile accompanied by high levels of IL-10 while the late phase showed a Th2 immune profile.

Magnetic resonance imaging of infectious meningitis and ventriculitis in adults

Magnetic resonance imaging findings of meningitis are usually nonspecific with respect to the causative pathogen because the brain response to these insults is similar in most cases. In this article, we will use a few representative cases to describe the characteristic magnetic resonance findings of meningitis and its complications, including ventriculitis.

Extraparenchymal (Racemose) Neurocysticercosis and Its Multitude Manifestations: A Comprehensive Review

Neurocysticercosis is an infection of the central nervous system caused by the larval form of the pork tapeworm Taenia solium. In the brain it occurs in two forms: parenchymal and extraparenchymal or racemose cysts. The clinical presentation of racemose cysts is pleomorphic, and is quite different from parenchymal cysticercosis. The clinical diagnosis of racemose cysts is quite challenging, with neuroimaging being the mainstay. However, the advent of newer brain imaging modalities has made a more accurate diagnosis possible. The primary focus of this article is racemose neurocysticercosis and its multitude manifestations, and includes a discussion of the newer diagnostic modalities and treatment options.

Hydrocephalus and neurocysticercosis: cases illustrative of three distinct mechanisms

Background

Cysticercosis is the most frequent parasitic infection of the nervous system. Most lesions are intracranial, and spinal involvement is rare. We describe here in two cases of neurocysticercosis (NCC) in the brain and one in the spinal cord that illustrate three distinct mechanisms leading to symptomatic acute hydrocephalus.

Case Report

Hydrocephalus was related to intracranial NCC in two of them. In the first case the hydrocephalus was due to an extensive arachnoiditis to the craniocervical junction, while in the second it was caused by obstruction of Magendie's foramen in the fourth ventricle by the scolex of Taenia solium. For the third patient, hydrocephalus revealed cysticercosis of the cauda equina due to the scolex.

Conclusions

NCC should be considered as a possible diagnosis for patients suffering from hydrocephalus when they originate from or have traveled in endemic areas, MRI of the spine is mandatory to search for intraspinal lesions.

Hydrocephalus in neurocysticercosis

INTRODUCTION

Cysticercosis (CC) is the most important of the parasitic diseases of the central nervous system due to its high incidence in the world. CC is the infection with the larval cysts of Taenia solium. It is the most common helminthic infection of the nervous system and is endemic in most underdeveloped countries as well as in industrialized nations. It is estimated that approximately 50,000 people die every year from neurocysticercosis (NCC) worldwide.

DISCUSSION

Humans with CC are incidental intermediate hosts, which replace the pig in the life cycle of the T. solium. Children are more frequently affected by parenchyma infestation of cysticercus, of which the main clinical manifestation is epilepsy. Hydrocephalus is more common in adults and is caused by cerebrospinal fluid blockage by ventricular cysts and inflammatory reactions (ependimitis/arachnoiditis). Treatment should be individualized based on clinical presentation, degree of infestation, location and viability of cysticercus, and host response. Hydrocephalus can be controlled only by removal of obstructive intraventricular cysts or associated with either ventriculoperitoneal shunt or endoscopic third ventriculostomy. The degree of infestation and complications related to the shunt represents the most important prognostic factors in the outcome of NCC.

Diagnosis and treatment of neurocysticercosis

Neurocysticercosis, the infection caused by the larval form of the tapeworm Taenia solium, is the most common parasitic disease of the central nervous system and the most common cause of acquired epilepsy worldwide. This has primarily been a disease that remains endemic in low-socioeconomic countries, but because of increased migration neurocysticercosis is being diagnosed more frequently in high-income countries. During the past three decades improved diagnostics, imaging, and treatment have led to more accurate diagnosis and improved prognosis for patients. This article reviews the current literature on neurocysticercosis, including newer diagnostics and treatment developments.

Neurocysticercosis

Cysticercosis is an infection caused by Taenia solium larvae (cysticerci). When the cysticercus is lodged in the central nervous system (CNS), the disease is known as neurocysticercosis (NCC). NCC is the most frequent and most widely disseminated human neuroparasitosis. It is endemic in many parts of the world, particularly Latin America, Africa, and Asia, and still relatively frequent in Portugal, Spain and Eastern European countries It is also endemic in developed countries with high rates of immigration from endemic areas. Man may act as an intermediate host after ingestion of mature, viable T. solium eggs via the fecal-oral route. The development of lesions in the brain and leptomeninges, and the consequent of onset of symptoms associated with NCC are mainly due to the host immune-inflammatory response. As long as the cysticercus remains viable, there is relative host immune tolerance. It is only when the parasite dies that massive antigen exposure occurs, with intensification of the immune response/inflammatory reaction and the appearance or worsening of symptoms. NCC can be asymptomatic or cause widely varied clinical manifestations, such as seizures, increased intracranial pressure, ischemic cerebrovascular disease, dementia, and signs of compression of the spinal roots/cord. The combination of two or more symptoms is common. Such clinical polymorphism is determined by 1) the number of lesions (single or multiple cysticerci); 2) the location of CNS lesions (subarachnoid, intracerebral, intraventricular, intramedullary); 3) the type of cysticercus (Cysticercus cellulosae, Cysticercus racemosus); 4) the stage of development and involution of the parasite (vesicular or viable, necrotic, fibrocalcified nodule); and 5) the intensity of the host immune-inflammatory response (no inflammatory reaction, leptomeningitis, encephalitis, granular ependymitis, arteritis).

Intraventricular neurocysticercus cyst(s) in Indian children

Eleven cases of intraventricular neurocysticercosis were managed over a 10-year period. All patients presented with features of hydrocephalus. In 9 cases the cysts were blocking the cerebrospinal fluid (CSF) pathway resulting in hydrocephalus. The 4 cases of lateral ventricular cyst had communicating hydrocephalus, while 2 of these had asymmetrical ventriculomegaly. Two of 4 cases had more than one cyst. One of 4 children with lateral ventricular cyst had narrowing of the foramen of Monro causing asymmetrical hydrocephalus. Following cyst removal, CSF diversion was not required in 6 cases, while 5 required CSF diversion despite removal of their cysts in 4 of 5. One patient had a cyst at the aqueductal inlet and he was managed by shunt and albendazole therapy. Thus, we managed 6 of our cases with excision of the cysts obstructing the CSF pathway, and in 4 cases excision of cysts with ventriculoperitoneal shunt was adequate.

Diagnosis of intraventricular cysticercosis by magnetic resonance imaging: Improved detection with three-dimensional spoiled gradient recalled echo sequences

Neurocysticercosis (NCC) is caused when the cysticercus larvae of Taenia solium infect the central nervous system. The larvae usually land in the parenchymal tissue, but quite rarely can lodge in the ventricles and cisterns of the brain. Unlike parenchymal NCC, it is not easy to demonstrate the cysticercus cysts within the cerebrospinal fluid spaces. Computed tomography and even conventional MR sequences can fail to detect such cysts. However, obtaining three-dimensional spoiled gradient recalled echo imaging sequences can help in improving the detection of intraventricular NCC, as is borne out by a case described in the present report. The use of such special MR sequences is therefore strongly advocated in suspected cases of intraventricular NCC.

Intraventricular neurocysticercosis mimicking colloid cyst. Case report

The authors recently encountered a unique case of anterior third ventricular neurocysticercosis in which the cyst exhibited an unusually high signal on T1-weighted magnetic resonance imaging. The lesion's signal intensity and location made differentiation from colloid cyst difficult. Intraventricular neurocysticercosis should be included in the differential diagnosis of a colloid cyst.

Intraventricular neurocysticercosis: 18 consecutive patients and review of the literature

Object

The prognosis for intraventricular neurocysticercosis (IVNCC) is poorer than that for parenchymal NCC, making prompt diagnosis and treatment especially important. Although active, viable intraventricular cysts produce no reaction in the host; they can cause noncommunicating hydrocephalus, the onset of which is frequently abrupt. With the death of the larva comes a local granulomatous ependymitis, generalized ventriculitis, and meningoencephalitis. The authors report on 18 patients with IVNCC (accrued from a larger case series of 62 patients with NCC treated over an 11-year period), detailing clinical presentation, neuroimaging findings, treatment, and outcome.

Methods

All patients presented with hydrocephalus and/or meningitis. The most valuable diagnostic tests were magnetic resonance imaging of the brain and EITB of serum and/or cerebrospinal fluid. Treatment included albenda-zole and steroid therapy in all cases, and when necessary in cases requiring urgent or emergency ventriculostomy and/or surgical removal of the obstructing cyst (followed by shunt placement if indicated).

Conclusions

An extensive review of the literature on IVNCC has been prepared, with the goal of providing the reader with the information necessary to diagnose and treat this complex and potentially fatal disease in a timely and effective manner.

Neurocysticercosis: updates on epidemiology, pathogenesis, diagnosis, and management

Neurocysticercosis is now recognized as a common cause of neurologic disease in developing countries and the United States. The pathogenesis and clinical manifestations vary with the site of infection and accompanying host response. Inactive infection should be treated symptomatically. Active parenchymal infection results from an inflammatory reaction to the degenerating cysticercus and will also respond to symptomatic treatment. Controlled trials have not demonstrated a clinical benefit for antiparasitic drugs. Ventricular neurocysticercosis often causes obstructive hydrocephalus. Surgical intervention, especially cerebrospinal fluid diversion, is the key to management of hydrocephalus. Shunt failure may be less frequent when patients are treated with prednisone and/or antiparasitic drugs. Subarachnoid cysticercosis is associated with arachnoiditis. The arachnoiditis may result in meningitis, vasculitis with stroke, or hydrocephalus. Patients should be treated with corticosteroids, antiparasitic drugs, and shunting if hydrocephalus is present.

Cysticercosis and epilepsy: a critical review

Neurocysticercosis (NC) remains a major public health problem in developing and some developed countries. Currently, the best procedures for diagnosing NC are neuroimaging studies. Immunoserologic assays, such as enzyme-linked immunoelectrotransfer blot assay (EITB) or enzyme-linked immunosorbent assay (ELISA), detect antibodies against Taenia solium, or cysticercus. Consequently, they are useful in identifying a population at risk of contact with the parasite but do not necessarily indicate a systemic active infection. Most seropositive individuals are asymptomatic. No data from prospective studies concern the proportion of these individuals that will develop seizures or other neurologic symptoms. There is a discrepancy between the results of serologic assays and neuroimaging studies: >50% of those individuals with NC diagnosed by computed tomography (CT) scan test EITB negative. Pathophysiologic classification of NC into active, transitional, and inactive forms permits a good correlation between clinical manifestations and neuroimaging procedures and facilitates medical and surgical management and research. The most frequent clinical manifestations of NC are seizures. We assume that NC is the main cause of symptomatic epilepsy in developing countries; however, no case-control or cohort studies demonstrate this association. Most patients with NC with seizures have a good prognosis; nevertheless, further studies analyzing factors related to recurrence of seizures and possibilities of discontinuation of antiepileptic medications (AEDs) are needed. Regarding treatment of NC with antihelminthic drugs, no controlled clinical trials exist that establish specific indications, definitive doses, and duration of treatment. The most effective approach to taeniasis/cysticercosis infection is prevention. This should be a primary public health focus for developing countries. We critically review the available information regarding the epidemiology and diagnosis of human cysticercosis, the physiopathology and imaging correlation of the parasite in the central nervous system (CNS) of the host, the relation between seizures or epilepsy and NC, and the issues surrounding the treatment and prognosis of NC, including the use of antihelminthic therapy.

Uncommon presentations of neurocysticercosis

Neurocysticercosis commonly presents with seizures, raised intracranial tension and dementia. The unusual location of the cysts may result in uncommon manifestations mimicking a host of neurological disorders. Ten patients with neurocysticercosis with rare clinical presentations have been described in this series. These include dorsal midbrain syndrome, isolated bilateral ptosis, papillitis, cerebral hemorrhage, painful cervical radiculopathy, progressive swelling of arm, paraplegia due to intramedullary cyst, third ventricular cyst, dystonia and nominal aphasia masquerading as transient ischaemic attacks. The clinical details and possible mechanisms for these rare presentations are discussed.

Third ventricular cysticercal cyst mimicking a colloid cyst: case report

We describe a case of a 28-year-old Latino man who presented with signs and symptoms of raised intracranial pressure and radiographic evidence of a third ventricular cystic lesion. The cyst was removed via a transcallosal approach; the histology was noted to be a cysticercal lesion. The radiographic and histological features of this interesting case are discussed.

Racemose neurocysticercosis after chronic meningitis: effect of medical treatment

A patient affected by racemous neurocysticercosis, occurring 5 years after the onset of chronic meningitis and followed by sequential MRI studies, is described. After ventriculo-peritoneal shunt, he was successfully treated with Praziquantel and Albendazole. This case may contribute to understand the natural history of the disease and stress the efficacy of medical versus surgical treatment of this lifethreatening disease.