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

Neurocysticercosis presenting as a locked-in lateral ventricle: A case report and evidence-based review

Human neurocysticercosis is one of the most prevalent parasitic infestations of the central nervous system. It is considered the most frequent underlying etiology of acquired epilepsy in endemic areas in Central and South America, East Europe, Africa, and Asia, with over 50 million people affected globally. Ventricular involvement is a severe form of neurocysticercosis commonly manifests as arachnoiditis, raised intracranial pressure, or hydrocephalus, secondary to CSF flow obstruction of the ventricular system by cysts of Taenia solium, hence requiring prompt, aggressive intervention to alleviate the increased intracranial pressure to prevent imminent lethal complications. Ventricular neurocysticercosis can involve any brain ventricle but with a paramount preference for the fourth ventricle, causing non-communicating hydrocephalus and symmetric ventriculomegaly. However, in this clinical report, we present an uncommon case of trapped (locked-in) lateral ventricle caused by an isolated cysticercus trapped at the ipsilateral foramen of Monro, which is an atypical location for neurocysticercosis, adding more challenges to diagnosis and during the process of surgical extraction. We additionally provide a comprehensive, evidence-based review of the clinical course and management options relevant to the entity of ventricular neurocysticercosis, besides recent relevant clinical updates.

A hidden infection: Racemose neurocysticercosis causing hydrocephalus; a case report

Introduction and importance

Neurocysticercosis (NCC) is the most common helminthic central nervous system infection (CNS) in the Western hemisphere and the most common cause of acquired epilepsy worldwide. Due to its relatively prolonged latent period and clinical similarity to other infectious diseases – including bacterial or viral meningitis and other helminthic infections – NCC may be difficult to diagnose, especially for clinicians who rarely encounter it.

Case presentation

This case report discusses a patient with obstructive hydrocephalus and eosinophilic meningitis secondary to racemose NCC. The diagnosis process was initially complicated by the patient's history of pork allergy and absence of radiographic evidence of helminthic CNS infection. Further investigation showed a 4th ventricle multi-cystic lesion causing hydrocephalus which prompted a surgical intervention with a ventriculoperitoneal shunt (VPS) in conjunction with anti-helminthic medical treatment. At 1-year follow-up, the patient has reported recurrence of VPS related complications.

Clinical discussion

Larval cysts typically deposit within the brain parenchyma, making them easily detected on head computed tomography (CT) scans and leading to neurologic sequelae such as epilepsy. In this case, the absence of CT evidence of NCC and the patient's lifelong history of pork allergy slowed the diagnosis process.

Conclusion

Racemose NCC is a rare subset of the disease in which cyst clusters occupy the extra parenchymal space, thereby changing the symptomatic profile and making the cysts more difficult to visualize in imaging studies. In this case, magnetic resonance imaging (MRI) was the best imaging modality to diagnosis extra parenchymal NCC and guide its surgical management.

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NCC causes parasitic infections in the brain and acquired epilepsy.

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Racemose is a rare form of NCC affecting the extra parenchymal space in the brain.

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Making the diagnosis of NCC is challenging, requiring advanced neuroimaging studies.

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This case report describes racemose NCC complicated by obstructive hydrocephalus.

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Ventriculoperitoneal shunt and anti-parasitic medicines were successful treatments.

Neurocysticercosis: An Uncommon Cause of Acute Supratentorial Hydrocephalus

We report a 29-year-old woman with acute supratentorial hydrocephalus due to intraventricular neurocysticercosis (NC). Aqueductal stenosis due to web formation and a free floating intraventricular cyst with scolex were pathognomonic and led to the diagnosis of NC. Worldwide, NC is the most important parasitic infection of the central nervous system but is very uncommon in non-endemic regions. Intraventricular abnormalities occur in approximately 30% of the patients. Magnetic resonance imaging (MRI) plays a crucial role in the diagnostic work-up and in guiding intervention.

Teaching Point: Brain magnetic resonance imaging in intraventricular neurocysticercosis is pathognomonic and essential in guiding treatment.

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.

New diagnostic criteria for neurocysticercosis: Reliability and validity

Objective

The diagnosis of neurocysticercosis (NCC) remains problematic because of the heterogeneity of its clinical, immunological, and imaging characteristics. Our aim was to develop and assess a new set of diagnostic criteria for NCC, which might allow for the accurate detection of, and differentiation between, parenchymal and extraparenchymal disease.

Methods

A group of Latin American NCC experts developed by consensus a new set of diagnostic criteria for NCC. A multicenter, retrospective study was then conducted to validate it. The reference standard for diagnosis of active NCC was the disappearance or reduction of cysts after anthelmintic treatment. In total, three pairs of independent neurologists blinded to the diagnosis evaluated 93 cases (with NCC) and 93 controls (without NCC) using the new diagnostic criteria. Mixed‐effects logistic regression models were used to estimate sensitivity and specificity.

Results

Inter‐rater reliability (kappa) of diagnosis among evaluators was 0.60. For diagnosis of NCC versus no NCC, the new criteria had a sensitivity of 93.2% and specificity of 81.4%. For parenchymal NCC, the new criteria had a sensitivity of 89.8% and specificity of 80.7% and for extraparenchymal NCC, the new criteria had a sensitivity of 65.9% and specificity of 94.9%.

Interpretation

These criteria have acceptable reliability and validity and could be a new tool for clinicians and researchers. An advantage of the new criteria is that they consider parasite location (ie, parenchymal or extraparenchymal), which is an important factor determining the clinical, immunological, and radiological presentation of the disease, and importantly, its treatment and prognosis. Ann Neurol 2016;80:434–442

Natural course of typical and atypical parenchymal solitary cysticercus granuloma of the brain: a 3-year prospective clinico-radiological study

OBJECTIVE

To evaluate the role of advanced magnetic resonance (MR) sequences (fast imaging employing steady-state acquisition (FIESTA), T2 star-weighted angiography (SWAN) and spoiled gradient recalled echo (SPGR)) in patients with single small enhancing computed tomography lesions and scolex demonstration in typical and atypical parenchymal neurocysticercosis.

METHODS

In this study, 59 patients of new-onset seizures with single small enhancing computed tomography lesions of the brain were included. Along with routine MR sequences, advanced MR sequences, like SWAN, FIESTA, and pre and post-contrast SPGR, were performed. Follow-up MR studies focussing on the morphology of the lesions and demonstration of scolex were performed 6 monthly for 3 years.

RESULTS

The majority of patients (62.7%) were men with partial seizure as the most common manifestation. On SPGR, contrast lesions were identified as either 'typical' (42, 71.2%) or 'atypical' (17, 28.8%). In the typical lesion group, SWAN and FIESTA sequences detected scolex in 30 (71.4%) and 32 (76.2%), respectively. The combination of SPGR-contrast, FIESTA and SWAN sequences detected scolex in 35 (83.3%) patients compared to 19 (45.2%) by routine sequences (P < 0.001). In the atypical lesion group, SWAN and FIESTA sequences detected scolex in 15 (88.2%) and 16 (94.1%) patients, respectively. The combination of SPGR-contrast, FIESTA and SWAN sequences detected scolex in 16 (94.1%) patients compared to 10 (58.8%) by routine sequences (P < 0.001). Follow-up showed greater resolution with lesser calcification in the typical group compared to the atypical group.

CONCLUSION

This study provides an insight into the natural course of typical and atypical solitary cysticercus granuloma lesions, and the utility of SPGR-contrast, FIESTA and SWAN MR sequences in scolex demonstration and identification of atypical lesions.

Relevance of 3D magnetic resonance imaging sequences in diagnosing basal subarachnoid neurocysticercosis

Imagenological diagnosis of subarachnoid neurocysticercosis is usually difficult when classical magnetic resonance imaging (MRI) sequences are used. The purpose of this study was to evaluate the advantages of 3D MRI sequences (Fast Imaging Employing Steady-state Acquisition (FIESTA) and Spoiled Gradient Recalled Echo (SPGR)) with respect to classical sequences (Fluid Attenuation Inversion Recovery (FLAIR) and T1) in visualizing Taenia solium cyst in these locations. Forty-seven T. solium cysts located in the basal cisterns of the subarachnoid space were diagnosed in eighteen Mexican patients. A pre-treatment MRI was performed on all patients, and all four sequences (FIESTA, FLAIR, T1 SPGR, and T2) were evaluated independently by two neuroradiologists. The sensitivity of each sequence to detect the parasite membrane and scolex was evaluated, along with its capacity to detect differences in signal intensity between cerebrospinal fluid (CSF) and cysts. FIESTA sequences allowed the visualization of cyst membrane in 87.2% of the parasites evaluated, FLAIR in 38.3%, SPGR in 23.4%, and T2 in 17.0%. The superiority of FIESTA sequences over the other three imaging methods was statistically significant (P<0.001). Scolices were detected by FIESTA twice as much as the other sequences did, although this difference was not significant (P>0.05). Differences in signal intensity between CSF and parasite cysts were significant in FIESTA (P<0.0001), SPGR (P<0.0001), and FLAIR (P=0.005) sequences. For the first time, the usefulness of 3D MRI sequences to diagnose T. solium cysts located in the basal cisterns of the subarachnoid space was demonstrated. The routine use of these sequences could favor an earlier diagnosis and greatly improve the prognosis of patients affected by this severe form of the disease.

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.

Three-day versus 15-day course of albendazole therapy in solitary cysticercus granuloma: an open label randomized trial

BACKGROUND

Albendazole therapy has been found effective in solitary cysticercus granuloma. An optimal duration of albendazole therapy is not exactly known. Even 3-day therapy has been found effective.

METHODS

We included 105 patients of new-onset seizures and solitary cysticercus granuloma. We compared 3-day albendazole therapy and 15-day therapy with a control group. Each group had 35 patients. This was an open-label randomized trial. Patients were followed for 6 months. MRI was done after 6 months. Seizure recurrences during follow-up were noted.

RESULTS

After 6 months, albendazole group, in comparison to placebo group, had significantly higher proportion (43/70 versus 13/35) of patients in whom lesion had disappeared. Albendazole treatment for 15 days was insignificantly better in comparison to 3-day treatment regimen. In 15-day albendazole group lesser number of lesions (2.8%) was calcified than 3-day albendazole group (8.57%) or no treatment group (20%). After 6 months of follow-up, seizure recurrence was seen in 20 (19%) patients. The majority (15/20) of patients, experiencing seizure recurrence, had an abnormal follow-up MRI. Five patients had seizures despite normal MRI.

CONCLUSION

In conclusion, albendazole was significantly better in producing lesion resolution. A 15-day treatment with albendazole was better than 3-day treatment. Albendazole, possibly, led to less number of lesions got calcified and possibly, there was less risk of seizure recurrence.

The role of 3D volumetric MR sequences in diagnosing intraventricular neurocysticercosis: preliminar results

OBJECTIVE

The purpose of this paper was to investigate the role of two three-dimensional magnetic resonance (MRI) sequences: enhanced spoiled gradient recalled echo (SPGR), and fast imaging employing steady-state acquisition (FIESTA) in the evaluation of intraventricular neurocysticercosis cysts and scolices.

METHOD

Seven neurocysticercosis patients suspected of presenting intraventricular lesions were evaluated by magnetic resonance imaging using enhanced SPGR, and FIESTA.

RESULTS

Enhanced SPGR detected eight cystic lesions, with scolices in four. Contrast enhancement was observed in three cysts. FIESTA also detected eight cystic lesions with the presence of scolices in seven of those cystic lesions. Four patients presented parenchymal involvement, while the remaining three presented the racemose form.

CONCLUSION

FIESTA and SPGR are sequences that can detect intraventricular cysts of neurocysticercosis, and FIESTA also is good for the detection of the scolex. Considering this information we suggest that FIESTA and SPGR should be included in the MRI protocol for the investigation of intraventricular neurocysticercosis.

Neurocysticercosis

Neurocysticercosis (NCC) is the most common cause of acquired epilepsy in developing countries. It can present variably depending on the location and stage of cysts in the nervous system, and the host immune response. The most common presentation of parenchymal NCC is with seizures that are usually focal and brief; status epilepticus occurs in some cases. About a third of cases have headache and vomiting. Diagnosis is made by either CT or MRI. Single, small, contrast enhancing lesions are the most common; visualization of a scolex is diagnostic. Some cases have multiple cysts with a characteristic starry-sky appearance. Although treatment with cysticidal therapy continues to be debated, there is increasing evidence that it helps through increased and faster resolution of CT lesions; whether there is any improvement in long-term seizure control needs further study. It should not be used in cysticercus encephalitis or in ophthalmic NCC and used with caution in extraparenchymal NCC. It is of no use in calcified lesions. Corticosteroids are used simultaneously to reduce cerebral oedema. Seizures respond well to a single antiepileptic, and the seizure recurrence rate is low in cases with single lesions; those with multiple, persistent or calcified lesions usually have recurrent seizures. Extraparenchymal NCC is often associated with intracranial hypertension, hydrocephalous and chronic meningitis; it has a guarded prognosis; surgical intervention is required in many cases. Management of NCC needs to be individualized. NCC is potentially eradicable; proper sanitation, hygiene and animal husbandry are warranted.

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.

Evaluation of Taenia solium and Taenia crassiceps cysticercal antigens for immunodiagnosis of neurocysticercosis using ELISA on cerebrospinal fluid samples

The efficacy of whole parasite and vesicular fluid antigen extracts from Taenia solium and Taenia crassiceps cysticerci for immunodiagnosis of neurocysticercosis was evaluated using ELISA on cerebrospinal fluid samples. Anticysticercal IgG antibodies were assayed in cerebrospinal fluid samples from 23 patients with neurocysticercosis and 35 patients with other neurological disorders. The ELISA reaction for the whole Taenia solium cysticercal extract showed 91.3% sensitivity and 94.3% specificity, whereas the sensitivity and specificity of the ELISA for the whole Taenia crassiceps cysticercal extract were 87% and 94.3%, respectively. The ELISA reactions for vesicular fluid from Taenia solium or Taenia crassiceps showed 91.3% sensitivity and 97.1% specificity. Considering the results obtained from the four antigen preparations, vesicular fluid from Taenia solium and Taenia crassiceps cysticerci may be useful as a source of antigens for immunological reactions that are used for detecting specific antibodies in cerebrospinal fluid samples from patients with neurocysticercosis.

Intrathecal synthesis of specific immunoglobulin G antibodies in neurocysticercosis: evaluation of antibody concentrations by enzyme-linked immunosorbent assay using a whole cysticercal extract and cyst vesicular fluid as antigens

The demonstration of intrathecal antibody production has proven useful for showing the involvement of the central nervous system (CNS) in several diseases. In the present study, the intrathecal synthesis of cysticercus-specific immunoglobulin G (IgG) antibodies was investigated in 30 patients with neurocysticercosis based on calculation of the specific IgG antibody index (AI(IgG)). An AI(IgG) > or =1.5 was considered to be indicative of intrathecal antibody production. Antibody concentrations in serum and cerebrospinal fluid samples were evaluated using an enzyme-linked immunosorbent assay with 2 antigen preparations from Taenia solium cysticerci, namely, a whole cysticercal extract (TsoW) and the vesicular fluid of the parasite (TsoVF). Intrathecal, cysticercus-specific IgG antibody synthesis was observed in 21 (70%) and 23 (76.6%) patients using the TsoW and TsoVF antigens, respectively. The detection of the intrathecal synthesis of specific antibodies may be a potentially useful tool in establishing the involvement of CNS in cysticercosis.