Third-ventricular neurocysticercosis: hydraulic maneuvers facilitating endoscopic resection

A case-based review on the neuroendoscopic management of intraventricular and subarachnoid basal neurocysticercosis

OBJECTIVE

Extraparenchymal localization of neurocysticercosis (NCC) is rare in non-endemic areas. A case of mixed (intraventricular, IV, and subarachnoid basal, SAB) NCC was surgically treated using the neuroendoscope and a systematic review of the literature was performed with the aim to analyze the use of this instrument in the management of the extraparenchymal forms of the parasitic disease.

MATERIALS AND METHODS

Medline and Embase databases were searched for studies where the neuroendoscope was used for the management of IV/SAB NCC cysts, either for the cerebrospinal fluid diversion or cyst removal. Cyst location, complete removal, cyst breakage during removal, intraoperative and postoperative complications, administration of antihelmintic therapy, outcome and follow-up period were extracted from the articles.

RESULTS

281 patients were treated by means of the neuroendoscope. 254 patients who were described in retrospective cohort studies, came all from endemic areas, with no significant difference between sexes. Mean age at surgery was 30.7 years. Of all cysts reported in retrospective studies, 37.9% were located in the fourth ventricle. An attempt of cyst removal was described in the 84.6% of cases and an endoscopic third ventriculostomy was performed in another 76.4%. A small number of complications were reported intraoperatively (9.1%) obtaining, but a good recovery was achieved at follow-up. Only 17 ventriculoperitoneal shunts were placed after the first procedure, defining a low risk of postoperative hydrocephalus even in case of partial cyst removal.

CONCLUSION

Neuroendoscopic removal of an extraparenchymal NCC cyst is a safe procedure that should be preferred for lateral and third ventricle localization and, in a specialized centre, even for a localization in the fourth ventricle if feasible. It is also efficient because of the possibility of performing an internal CSF diversion concomitantly to cyst removal, avoiding the complication registered with VPS. The need for cysticidal treatment after surgery should be addressed in a prospective study.

Paediatric neurocysticercosis in high income countries

BACKGROUND

Neurocysticercosis (NCC) is an unusual cause of seizures in high income settings. It typically presents as an afebrile seizure in a previously well child and can occur years after migration or travel.

METHODS

Children diagnosed with neurocysticercosis from 01 July 2005 to 30 June 2020 were identified from the electronic medical records of a tertiary children's hospital in Australia. Additionally, a 10-year compilation of case reports of paediatric NCC in high income settings was performed by medline search (publication years 2011-2021). Diagnosis and treatment of neurocysticercosis were reviewed with reference to diagnostic criteria of Del Brutto et al., and the 2017 Infectious Diseases Society of America treatment guidelines.

RESULTS

Over a fifteen-year period, eight children were diagnosed with NCC at our hospital in Sydney, Australia. Seizures and history of travel to or migration from South Asia were the two most frequently occurring findings. Children diagnosed after 2016 all received antiparasitic therapy. Outcomes were generally favorable, though long-term epilepsy resulted in some cases. Compiled case reports from high income settings revealed migration and travel exposures commensurate with local demographic patterns, and treatment approaches conforming with 2017 Infectious Diseases Society of America guidelines.

CONCLUSIONS

Clinicians should be aware of NCC as a differential diagnosis in children from endemic areas presenting with unprovoked seizures as misdiagnosis can occur. Expert review of neuroimaging facilitates diagnosis and can avert unnecessary neurosurgery. In Australia, India was a key exposure country for NCC, reflecting its endemic burden of disease and local travel and migration patterns.

Non-communicating hydrocephalus from pork tapeworm obstructing the foramina of Monro and its endoscopic management; a case report from Europe

INTRODUCTION

Taenia solium is the main causative agent of neurocysticercosis. The tapeworm can manifest inside the ventricles, usually in the form of intracranial hypertension. We present a case of hydrocephalus as a result of a neurocysticercosis lesion obstructing both foramina of Monro.

RESEARCH QUESTION

A comprehensive review of the management is provided, as well as video footage (an invaluable resource to compare, critique and learn with other institutions).

MATERIAL AND METHODS

A 23-year-old female from Honduras presented with a 7-day complaint of headache. On exam, she was hyperreflexic, but otherwise normal. Magnetic resonance imaging (MRI) revealed a non-specific lesion at the level of the foramina of Monro, with associated hydrocephalus. Additional testing was normal.

RESULTS

The patient underwent an endoscopic ventriculoscopy with partial excision of the lesion and subsequent implantation of a ventriculoperitoneal shunt. On postoperative MRI, hydrocephalus resolved and pathological analysis identified the parasite as Taenia solium. Albendazole was administered for 14 days.

DISCUSSION AND CONCLUSION

Neurocysticercosis should be considered in patients presenting with hydrocephalus, especially those from endemic areas. The long-term prognosis of ventricular neurocysticercosis might be favourable, provided that adequate care is given timely. Endoscopic surgery seems to be effective for the removal of parasitic lesions. However, studies comparing open versus endoscopic surgery are lacking. The majority of cases in the literature correspond to America and Asia. This case shows that neurocysticercosis is also present in Europe, and that a high index of suspicion is necessary.

Endoscopic intervention for intraventricular neurocysticercal cyst: Challenges and outcome analysis from a single institute experience

OBJECTIVE

Endoscopic intervention is presently proposed as standard approach for the treatment of Intraventricular neurocysticercal cyst (IVNCC) as it helps to retrieve the cyst as well as CSF diversion. We present our series of 61 patients with IVNCC managed by endoscopic intervention and analyze the outcome.

METHOD

A retrospective analysis of 61 patients with IVNCC managed between 1998-2019 at our institute was performed. We reviewed the clinical details of consecutive patients, management, and outcome.

RESULTS

There were 61 patients with 34 males and 27 females. The mean age was 25 years. Fourth ventricular location is the most common (n = 34) followed by third ventricle(n = 14) and lateral ventricle (n = 13). Cyst retrieval could be done in 43 cases, while the cyst could not be retrieved in 18 cases due to intraventricular bleed, CSF turbidity, adhesion of cyst wall etc. Along with cyst retrieval, some patients underwent Endoscopic Third ventriculostomy, septostomy, foraminotomy for internal CSF diversion. Seven patients had a preoperative VP shunt surgery. The median follow-up was 12 months. Preoperative shunt (CI:1.33-62, P = 0.02) was associated with failure of cyst retrieval in univariate analysis as well as in multivariate regression analysis (CI: 0.02-0.94, P = 0.04). Two patients underwent shunt surgery at follow-up period due to the failure of endoscopic CSF diversion.

CONCLUSION

Endoscopic management of IVNCC is a safe and effective management option, avoiding an indwelling shunt system. Endoscopic third ventriculostomy should be considered for patients with IVNCC and hydrocephalus.

Creation of a novel simulator for minimally invasive neurosurgery: fusion of 3D printing and special effects

OBJECTIVE Recent advances in optics and miniaturization have enabled the development of a growing number of minimally invasive procedures, yet innovative training methods for the use of these techniques remain lacking. Conventional teaching models, including cadavers and physical trainers as well as virtual reality platforms, are often expensive and ineffective. Newly developed 3D printing technologies can recreate patient-specific anatomy, but the stiffness of the materials limits fidelity to real-life surgical situations. Hollywood special effects techniques can create ultrarealistic features, including lifelike tactile properties, to enhance accuracy and effectiveness of the surgical models. The authors created a highly realistic model of a pediatric patient with hydrocephalus via a unique combination of 3D printing and special effects techniques and validated the use of this model in training neurosurgery fellows and residents to perform endoscopic third ventriculostomy (ETV), an effective minimally invasive method increasingly used in treating hydrocephalus. METHODS A full-scale reproduction of the head of a 14-year-old adolescent patient with hydrocephalus, including external physical details and internal neuroanatomy, was developed via a unique collaboration of neurosurgeons, simulation engineers, and a group of special effects experts. The model contains "plug-and-play" replaceable components for repetitive practice. The appearance of the training model (face validity) and the reproducibility of the ETV training procedure (content validity) were assessed by neurosurgery fellows and residents of different experience levels based on a 14-item Likert-like questionnaire. The usefulness of the training model for evaluating the performance of the trainees at different levels of experience (construct validity) was measured by blinded observers using the Objective Structured Assessment of Technical Skills (OSATS) scale for the performance of ETV. RESULTS A combination of 3D printing technology and casting processes led to the creation of realistic surgical models that include high-fidelity reproductions of the anatomical features of hydrocephalus and allow for the performance of ETV for training purposes. The models reproduced the pulsations of the basilar artery, ventricles, and cerebrospinal fluid (CSF), thus simulating the experience of performing ETV on an actual patient. The results of the 14-item questionnaire showed limited variability among participants' scores, and the neurosurgery fellows and residents gave the models consistently high ratings for face and content validity. The mean score for the content validity questions (4.88) was higher than the mean score for face validity (4.69) (p = 0.03). On construct validity scores, the blinded observers rated performance of fellows significantly higher than that of residents, indicating that the model provided a means to distinguish between novice and expert surgical skills. CONCLUSIONS A plug-and-play lifelike ETV training model was developed through a combination of 3D printing and special effects techniques, providing both anatomical and haptic accuracy. Such simulators offer opportunities to accelerate the development of expertise with respect to new and novel procedures as well as iterate new surgical approaches and innovations, thus allowing novice neurosurgeons to gain valuable experience in surgical techniques without exposing patients to risk of harm.

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.

The Increase of Exotic Zoonotic Helminth Infections: The Impact of Urbanization, Climate Change and Globalization

Zoonotic parasitic diseases are increasingly impacting human populations due to the effects of globalization, urbanization and climate change. Here we review the recent literature on the most important helminth zoonoses, including reports of incidence and prevalence. We discuss those helminth diseases which are increasing in endemic areas and consider their geographical spread into new regions within the framework of globalization, urbanization and climate change to determine the effect these variables are having on disease incidence, transmission and the associated challenges presented for public health initiatives, including control and elimination.

Cervicomedullary neurocysticercosis causing obstructive hydrocephalus

We present a 45-year-old man with tussive headache and blurred vision found to have obstructive hydrocephalus from a neurocysticercal cyst at the cervicomedullary junction who underwent surgical removal of the cyst. We performed a suboccipital craniectomy to remove the cervicomedullary cyst en bloc. Cyst removal successfully treated the patient's headaches without necessitating permanent cerebrospinal fluid diversion. Neurocysticercosis is the most common parasite infection of the central nervous system causing seizures and, less commonly, hydrocephalus. Intraventricular cysts or arachnoiditis usually cause hydrocephalus in neurocysticercosis but craniocervical junction cysts causing obstructive hydrocephalus are rare. Neurocysticercosis at the craniocervical junction may cause Chiari-like symptoms. In the absence of arachnoiditis and leptomeningeal enhancement, surgical removal of the intact cyst can lead to favorable outcomes.