Current Role of Surgery in the Treatment of Neurocysticercosis.

Neurocysticercosis (NCC) is a common parasitic disease of the central nervous system (CNS) in low- and middle-income countries. The infection is pleomorphic, caused by the larval form of the cestode, Taenia solium, and part of the heterogeneity of its clinical presentations is associated with the localization of the parasite within the CNS. Changes in the current epidemiological trends of NCC indicate that extra-parenchymal NCC is proportionally becoming more frequent. Extraparenchymal NCC is commonly accompanied by raised intracranial hypertension due to hydrocephalus, which is an emergency requiring cyst extirpation by surgical intervention to relieve the symptoms. Although less frequent, parenchymal cysts may also reach giant sizes requiring urgent surgical treatment. Finally, there is an advancement in the comprehension of the association between NCC and epilepsy-and patients with drug-resistant seizures are candidates for surgical treatment. In this narrative review, we summarize the present state of knowledge to update the current trends in the role of surgery in the treatment of NCC.

Unruptured Brain Arteriovenous Malformations: A Systematic Review and Meta-Analysis of Mortality and Morbidity in Aruba-Eligible Studies.

BACKGROUND: Treating unruptured brain arteriovenous malformations (bAVMs) represent significant challenges, with numerous uncertainties still in debate. The ARUBA trial induced further investigation into optimal management strategies for these lesions. Here, we present a systematic-review and meta-analysis focusing on ARUBA-eligible studies, aiming to correlate patient data with outcomes and discuss key aspects of these studies. METHODS: Following PRISMA guidelines, we conducted a systematic-review. Variables analyzed included bAVM Spetzler-Martin (SM) grade, treatment modalities, and outcomes such as mortality and neurological deficits. We compared studies with a minimum of 50% cases classified as SM 1-2 lesions and those with less than 50% in this category. Similarly, a comparison between studies with at least 50% microsurgery-cases and those with less than 50% was performed. We examined correlations between mortality incidence, SM distribution, and treatment modalities. RESULTS: Our analysis included 16 studies with 2.417 patients. The frequency of bAVMs SM-grade 1-2 ranged from 44% to 76%, SM-grade 3 from 19% to 48%, and SM 4-5 from 5 to 23%. Notably, studies with more than 50% cases presenting lesions SM-grade 1-2 presented significantly lower mortality rates than those with less than 50% cases of SM 1-2 lesions (P < 0.001). No significant difference in mortality rates or neurological deficits was identified between studies with more than 50% of microsurgery-cases and those with less than 50%. CONCLUSIONS: The analysis revealed that studies with a higher proportion of bAVMs presenting SM 1-2 lesions were associated with lower mortality rates. Mortality did not show a significant association with treatment modalities.

Survival in patients undergoing surgical resection for brain metastasis from lung cancer and utility of different prognostic scales.

Brain metastases (BM) from lung cancer are among the most common intracranial tumors. Several studies have published scales to estimate the survival of patients with BM. Routine access to molecular diagnostics and modern oncologic treatments, including targeted therapy and immunotherapy, is limited in low- and middle-income countries (LMICs); therefore, incorporating them into recent prognostic scales may diminish the reliability of the scales in LMICs. This retrospective study aimed to determine the survival of 55 patients who were surgically treated for BM from lung cancer at a Brazilian public tertiary teaching hospital between 2012 and 2022. We determined clinical factors associated with survival, and compared observed survival rates with the estimated survival on prognostic scales. The mean overall survival (OS) was 9.3 months (range:0.2-76.5). At univariate analysis, female sex and improved postoperative Karnofsky performance status (KPS) score were associated with longer survival. The median survival did not differ between groups when classified using the Graded Prognostic Assessment (GPA)-2008, Lung-molecular GPA-2017, and Lung-GPA-2021 scales. According to the Diagnosis-Specific (DS)-GPA-2012 scale, there was a significant difference between the groups. In the multivariate Cox regression survival analysis, a higher DS-GPA-2012 and improved postoperative KPS score remained significantly associated with longer survival. In conclusion, this cohort showed a mean OS of < 1 year. Improved KPS score after surgery was associated with increased survival. This cohort DS-GPA scale demonstrated the highest concordance with observed survival, indicating its potential as a valuable tool for patient stratification in surgical treatment decision-making in LMICs.

Sexual dimorphism in the murine model of extraparenchymal neurocysticercosis.

Neurocysticercosis is a heterogeneous disease, and the patient's sex seems to play a role in this heterogeneity. Hosts' sexual dimorphism in cysticercosis has been largely explored in the murine model of intraperitoneal Taenia crassiceps cysticercosis. In this study, we investigated the sexual dimorphism of inflammatory responses in a rat model of extraparenchymal neurocysticercosis caused by T. crassiceps. T. crassiceps cysticerci were inoculated in the subarachnoid space of Wistar rats (25 females, 22 males). Ninety days later, the rats were euthanized for histologic, immunohistochemistry, and cytokines studies. Ten animals also underwent a 7-T magnetic resonance imaging (MRI). Female rats presented a higher concentration of immune cells in the arachnoid-brain interface, reactive astrogliosis in the periventricular region, in situ pro-inflammatory cytokine (interleukin [IL]-6) and anti-inflammatory cytokine (IL-10), and more intense hydrocephalus on MRI than males. Intracranial hypertension signals were not observed during the observational period. Overall, these results suggest sexual dimorphism in the intracranial inflammatory response that accompanied T. crassiceps extraparenchymal neurocysticercosis.

Risks for Oculomotor Nerve Palsy and Time to Recovery After Surgical Clipping of Posterior Communicating Artery Aneurysms: A Multicenter Retrospective Cohort Study.

BACKGROUND: Aneurysms of the posterior communicating segment of carotid artery (PcomA) have a high risk of rupture; when these nonruptured aneurysms are associated with oculomotor nerve palsy (ONP), the risk of rupture increases compared with asymptomatic nonruptured PcomA. OBJECTIVE: To retrospectively analyze the risk factors involved in ONP secondary to PcomA aneurysm and to study the factors involved in the recovery time of ONP once it is established. METHODS: This was a retrospective study of patients from 10 neurosurgery centers from October 2008 to December 2020. We analyzed age at diagnosis, presence of compressive neuropathy of the oculomotor nerve, presence of aneurysm rupture, largest aneurysm diameter, aneurysm projection, smoking, hypertension, diabetes, time between diagnosis and surgical treatment, as well as the outcome. RESULTS: Approximately 1 in 5 patients (119/511 23.3%) with a PcomA presented with ONP. We found that patients with aneurysms measuring greater than or equal to 7.5 mm were 1.6 times more likely to have ONP than those with aneurysms smaller than 7.5 mm. In our study, the prevalence of smoking in the PcomA + ONP group was 57.76%, and we also found that smokers were 2.51 times more likely to develop ONP. A total of 80.7% showed some degree of improvement, and 45.4% showed complete improvement with a median recovery time of 90 days. CONCLUSION: This study showed that 80.7% of patients with PcomA aneurysms undergoing surgical treatment with aneurysm clipping showed some degree of improvement of the ONP, with a median time to recovery between 90 and 120 days.

Contralateral Anterior Interhemispheric-Transcallosal-Transrostral Approach for the Resection of a Subcallosal Cavernous Malformation: A Case Report and an Operative Video.

This case report demonstrates the surgical resection of a cerebral cavernous malformation located in the subcallosal region. The authors present a detailed operative video explaining the steps to successfully remove the lesion through a contralateral interhemispheric-transcallosal-transrostral approach with the patient in lateral decubitus. The surgical procedure was uneventful, and the patient had no postoperative deficits and no residual lesions in a three-month follow-up.

Occipital Interhemispheric Transtentorial Approach for a Pineal Region Meningioma with Pseudobulbar Palsy.

Meningiomas represent 8%-10% of all pineal region (PR) tumors. When they arise from the falx, tentorium, or tentorial incisura, they are not always considered a true PR tumor, as they do not originate from it but instead only grow toward the region. The true meningioma of PR must be originated from the arachnoid envelope of the pineal gland or from the 2 leaflets of the velum interpositum. In both conditions there are no dural attachments.1,2 Occipital interhemispheric transtentorial and supracerebellar infratentorial are the 2 main approaches for tumors within this region. Aside from the surgeon's preference, the position of the venous system and the direction of the tumor growth guide the approach choice. Endoscope assistance can help reach areas unable to be visualized under the microscope.3-5 We report the case of a 37-year-old female with a large PR meningioma (velum interpositum) presenting with intense dysphagia, dysphonia, and bilateral tongue palsy. Given the affected bilateral upper motor tracts associated with bulbar symptoms, a diagnosis of pseudobulbar palsy was considered.6,7 Preoperative imaging also showed compression of the deep venous system. The patient underwent a total resection of the tumor via an occipital interhemispheric transtentorial approach and exhibited a dramatic recovery of neurologic symptoms after the surgery (Video 1). Postoperative venogram showed restoration of the usual deep venous system pattern, which may be associated with significant neurologic improvement. Careful management of the deep veins is mandatory during the resection of PR meningiomas. The venous system improvement after the surgery may be associated with the dramatic recovery seen in this unique case. The patient consented to publication of her images.

Higher Concentration of Taenia Antigens in the CSF is Related to Slight Ventricle Enlargement and Periventricular Neuronal Decrease in Young Rats

Purpose Experimental models might help understand the pathophysiology of neurocysticercosis-associated hydrocephalus. The present study aimed to compare the extent of hydrocephalus and tissue damage in rats with subarachnoid inoculation of different concentrations of Taenia crassiceps cyst proteins. Methods Sixty young rats were divided into two groups: low- and high-concentration groups. The animals in the low concentration group received 0.02ml of 2.4mg/ml T. crassiceps cyst proteins while those in the high concentration group received 0.02 ml of 11.6mg/ml T. crassiceps cyst proteins. The animals underwent magnetic resonance imaging at 1, 3, and 6 months postinoculation to assess the ventricle volume. Morphological assessment was performed at the end of the observation period. Results Repeated measures of ventricle volumes at 1, 3, and 6 months showed progressive enlargement of the ventricles. At 1 and 3 months, we observed no differences in ventricle volumes between the 2 groups. However, at 6 months, the ventricles were larger in the high concentration group (median » 3.86mm3, range: 2.37­12.68) compared with the low concentration group (median » 2.00mm3, range: 0.37­11.57), p » 0.003. The morphological assessment revealed a few inflammatory features in both groups. However, the density of oligodendrocytes and neurons within the periventricular region was lower in the high concentration group (5.18 versus 9.72 for oligodendrocytes and 15.69 versus 21.00 for neurons; p < 0.001 for both). Conclusion Our results suggest that, in rats, a higher concentration of T. crassiceps cyst proteins in the subarachnoid space could induce ventricle enlargement and reduce the number of neurons within the periventricular area.

Microscopic resection of a giant epidermoid tumor of the pineal region via supracerebellar infra and transtentorial approach with endoscope assistance.

The authors present a case of a 22-year-old male who developed hydrocephalus symptoms related to a giant epidermoid tumor at the pineal region. The surgical approach and technique for a large epidermoid tumor in this area are extensively discussed. A paramedian contralateral supracerebellar infratentorial and transtentorial approach was performed, with the patient in a semisitting position. The tumor was removed using a microscopic technique, and endoscope assistance was used in order to reach the areas unable to be visualized under the microscope. The patient was neurologically intact at his 2-year follow-up, and postoperative MRI showed a significant decrease in the tumoral volume. The video can be found here: https://stream.cadmore.media/r10.3171/2021.4.FOCVID2128.

Long-term follow-up of patients undergoing decompressive hemicraniectomy for malignant stroke: Quality of life and caregiver's burden in a real-world setting.

BACKGROUND AND PURPOSE: Decompressive hemicraniectomy is a life-saving procedure for the treatment of space-occupying middle cerebral artery infarctions (malignant stroke); however, patients may survive severely disabled. Comprehensive data on long-term sequelae outside randomized controlled trials are scarce. METHODS: We retrospectively evaluated the survival rates, quality of life, ability to perform activities of daily living, and caregiver burden of 61 patients (aged from 37 to 83) who had previously undergone decompressive hemicraniectomy for malignant stroke between 2012 and 2017. RESULTS: The mortality rate was higher among patients older than 60 years than among younger patients (71.0 % vs 36.7 %, p = 0.007; odds ratio 4.222, 95 % confidence interval 1.443-12.355). The mean survival time was 37.9 ± 6.0 months for 19 survivors of the younger group and 22.6 ± 5.7 months for 9 survivors of the older group. Among the 28 surviving patients, 22 (78.6 %) were interviewed, and we found that age was a determining factor for functional outcome (Barthel indices of 65.7 ± 10.6 for younger patients vs 48.0 ± 9.3 for older patients, p < 0.001), but not for quality of life. The caregiver burden was significantly correlated (R = -0.53, p < 0.01) with the severity of disability and age (R = 0.544, p = 0.011) of the patients. CONCLUSION: Our findings show that the degree of impairment, as well as caregiver burden, is higher in patients older than 60 years than in younger patients.

A Rat Model of Neurocysticercosis-Induced Hydrocephalus: Chronic Progressive Hydrocephalus with Mild Clinical Impairment.

BACKGROUND: Hydrocephalus is the most common complication of extraparenchymal neurocysticercosis, combining obstructive and inflammatory mechanisms that impair cerebrospinal fluid circulation. METHODS: We studied the long-term progression of neurocysticercosis-induced hydrocephalus in a rat model. We generated an experimental rat model of neurocysticercosis-induced hydrocephalus by cisternal inoculation of cysts or antigens of Taenia crassiceps and compared it with the classic model of kaolin-induced hydrocephalus. We used 52 animals divided into 4 groups: 1) control, 2) neurocysticercosis-induced hydrocephalus by cysts or 3) by antigens, and 4) kaolin-induced hydrocephalus. We studied behavioral, radiologic, and morphologic alterations at 1 and 6 months after inoculation by open field test, magnetic resonance imaging, and immunohistochemical localization of aquaporin-4 (AQP-4). RESULTS: Behavioral changes were observed later in neurocysticercosis-induced than in kaolin-induced hydrocephalic rats (P = 0.023). The ventricular volume of hydrocephalus induced by experimental neurocysticercosis progressively evolved, with the magnetic resonance imaging changes being similar to those observed in humans. Periventricular inflammatory and astrocytic reactions were also observed. AQP-4 expression was higher in the sixth than in the first month after inoculation (P = 0.016) and also occurred in animals that received antigen inoculation but did not develop hydrocephalus, suggesting that AQP-4 may constitute an alternative route of cerebrospinal fluid absorption under inflammatory conditions. CONCLUSIONS: Our neurocysticercosis-induced hydrocephalus model allows for the long-term maintenance of hydrocephalic animals, involving mild clinical performance impairments, including body weight and behavioral changes.

Hydrocephalus in Neurocysticercosis: Challenges for Clinical Practice and Basic Research Perspectives.

The objective of this paper is to discuss relevant data on the epidemiology of hydrocephalus in neurocysticercosis, the new knowledge coming from experimental studies, the pathophysiological mechanisms involved, and the controversies regarding clinical and surgical management, through a comprehensive review of the literature. Hydrocephalus is present at the onset of the disease in 16% to 51% of patients with neurocysticercosis and in 64% to 72% of patients with the extraparenchymal form of the disease. Animal models have successfully reproduced the disease and open new therapeutic approaches perspectives. Current guidelines suggest that, when hydrocephalus is due to viable cysts that can be excised surgically, cyst removal is recommended. On the other hand, degenerating cysts with protein discharge become fixed and evoke inflammation throughout the cerebrospinal fluid compartments. In these cases, surgical removal is risky, and ventriculoperitoneal shunts should be placed with close monitoring of infection and malfunction. Cysticidal treatment after shunt surgery is recommended in cases of cysts located in cerebral areas that prevent surgical management. In conclusion, mechanical obstruction and inflammation are the key pathophysiologic mechanisms in the development of neurocysticercosis-induced hydrocephalus. Anthelmintic drugs and surgical options should be used, but they have limitations. A better understanding of the disease can come from experimental models.

Effect of Albendazole Treatment in an Experimental Model of Neurocysticercosis-Induced Hydrocephalus

Hydrocephalus is a major concern in neurocysticercosis (NCC), and its management is more challenging than that of hydrocephalus caused by other etiologies. Even though albendazole is a well-established drug for the treatment of NCC, the death of the parasites may worsen the clinical symptoms and eventually, deteriorate the course of hydrocephalus. The aim of this study was to analyze the effects of treatment with albendazole on the course of hydrocephalus as well as on animal behavior in a ratmodel of NCC-induced hydrocephalus in order to verify whether the course of hydrocephalus and the animal behavior were changed. Ventricle volumes before and after treatment showed a slight but non-statistically significant difference (168.11 mm3 versus 184.98 mm3, p » 0.45). The distribution and location of the cysts were unaffected. In addition, the behavioral patterns before and after the treatment were not significantly different, as assessed by the open field test. On histologic assessment, mononuclear leukocyte infiltration was present in diverse sites, such as the perivascular and peri-ependymal regions, choroid plexus, and meningeal membranes. A positive correlation was found between the degree of ventricle enlargement and tissue damage. Further studies with long-term comparisons are required.