Long-term seizure outcomes following resection of supratentorial cavernous malformations

Intra-operative electrocorticography results and postoperative pathological findings are associated with epileptic outcomes in patients with cerebral cavernous malformations presenting with epilepsy

OBJECTIVES

The purpose of this study was to determine whether intraoperative electrocorticography (ECoG) results and postoperative pathological findings are associated with long-term epileptic outcomes in patients with cerebral cavernous malformations (CCMs).

METHODS AND MATERIALS

To identify all consecutive patients with surgically treated CCM-related epilepsy (CRE) referred to our hospital, our prospectively maintained database of patients with CCM was reviewed (NCT03467295). For these patients, an ECoG-guided extended lesionectomy was performed, in which the CCM, surrounding hemosiderin, and detected epileptic foci were removed. Intraoperative ECoG results and postoperative pathological findings were documented in detail. Engel Class I was defined as a favorable outcome, while Engel Class II-IV was considered an unfavorable outcome. The patients were followed up for at least 2 years. The relationship between ECoG results, postoperative pathological findings, and epileptic outcomes was analyzed.

RESULTS

A total of 522 patients with CCM were reviewed, and 85 patients with epileptic CCM were enrolled in this study. At the last clinical visit, 83.5 % of the patients experienced favorable postoperative outcomes. Multivariate analysis revealed that residual epileptic waves detected by intraoperative ECoG (OR 13.64; Cl 2.13-87.11; p = 0.006) and concomitant focal cortical dysplasia (FCD) (OR 11.37; Cl 1.63-79.27; p = 0.014) were independent factors significantly correlated with long-term epileptic outcomes. Most (61; 93.8 %) of the 65 patients with CRE without FCD achieved favorable outcomes.

CONCLUSION

Residual epileptiform discharges after excision and concomitant FCD may be associated with poorer long-term epileptic outcomes in patients with CRE. Close follow-up and strict administration of oral antiepileptic drugs may be needed for these patients.

Calcifying Pseudoneoplasm of the Neuraxis: From Pathogenesis to Diagnostic and Therapeutic Considerations

Calcifying pseudoneoplasm of the neuraxis (CAPNON) is a rare tumefactive lesion that can develop anywhere within the neuraxis. The incidence is likely underreported, given its nonspecific imaging features and because CAPNON has often been overwhelmed by the presence of comorbid disease. CAPNON is typically diagnosed by the histopathological examination findings. However, the histopathological diagnosis is often challenging owing to the existence of similar calcifying pathological entities. Although the pathogenesis of CAPNON has remained elusive, emerging evidence supports a reactive proliferative and immune-mediated process involving the aggregation of neurofilament light chain protein and the infiltration of immune cells. The management of CAPNON is largely dependent on the symptoms, which are mainly related to the location and associated mass effects. Maximal surgical resection will result in excellent patient outcomes with rare recurrence, especially in patients presenting with epilepsy. The discovery of neurofilament light chain protein within CAPNON suggests that neurofilament might be implicated in the pathogenesis of CAPNON, serve as an immunohistochemical marker to improve the diagnostic accuracy of CAPNON, and hold therapeutic potential for the treatment of CAPNON.

Prosopagnosia seizure semiology in a 10-year-old boy: a functional neuroimaging study

We illustrate a case of post-traumatic recurrent transient prosopagnosia in a paediatric patient with a right posterior inferior temporal gyrus haemorrhage seen on imaging and interictal electroencephalogram abnormalities in the right posterior quadrant. Face recognition area mapping with magnetoencephalography (MEG) and functional MRI (fMRI) was performed to clarify the relationship between the lesion and his prosopagnosia, which showed activation of the right fusiform gyrus that colocalised with the lesion. Lesions adjacent to the right fusiform gyrus can result in seizures presenting as transient prosopagnosia. MEG and fMRI can help to attribute this unique semiology to the lesion.

Treatment of Cerebral Cavernous Malformations Presenting With Seizures: A Systematic Review and Meta-Analysis

Background: Cerebral cavernous malformations (CCMs) presenting with seizures can be treated with neurosurgery or radiosurgery, but the ideal treatment remains unclear. Currently, there is no adequate randomized controlled trial comparing surgical treatment and radiotherapy for epileptogenic CCMs. Therefore, we conducted a systematic review and meta-analysis of available data from published literature to compare the efficacy and safety of neurosurgery and radiosurgery for epileptogenic CCMs. Methods: We performed a comprehensive search of the Ovid MEDLINE, Web of Science, PubMed, China Biological Medicine and China National Knowledge Infrastructure databases for studies published between January 1994 and October 2019. The search terms were as follows: "epilepsy," "seizures," "brain cavernous hemangioma," "cerebral cavernous malformation," "cerebral cavernous hemangioma," "hemangioma, cavernous, central nervous system." Two researchers independently extracted the data and reviewed all the articles. We compared the advantages and disadvantages of the two treatments. Results: A total of 45 studies were included in our analysis. Overall, the seizure control rate was 79% (95% CI: 75-83%) for neurosurgery and 49% (95% CI: 38-59%) for radiosurgery. In the neurosurgery studies, 4.4% of patients experienced permanent morbidity, while no patients in the radiotherapy studies had permanent morbidity. In addition, the results of subgroup analysis showed that ethnicity, CCMs location and average lesion number are likely significant factors influencing the seizure outcome following treatment. Conclusions: The epilepsy control rate after neurosurgery was higher than that after radiosurgery, but neurosurgery also had a relatively higher rate of permanent morbidity.

Advances in the Surgical Management of Epilepsy: Drug-Resistant Focal Epilepsy in the Adult Patient

Pharmacoresistant seizures occur in nearly one-third of people with epilepsy. Medial temporal lobe and lesional epilepsy are the most favorable surgically remediable epileptic syndromes. Successful surgery may render the patient seizure-free, reduce antiseizure drug(s) adverse effects, improve quality of life, and decrease mortality. Surgical management should not be considered a procedure of "last resort." Despite the results of randomized controlled trials, surgery remains an underutilized treatment modality for patients with drug-resistant epilepsy (DRE). Important disparities affect patient referral and selection for surgical treatment. This article discusses the advances in surgical treatment of DRE in adults with focal seizures.

Intraoperative MRI-assisted neuro-port surgery for the resection of cerebral intraparenchymal cavernous malformation

Background

Intraparenchymal cerebral cavernous malformation is difficult to localize intraoperatively with conventional frameless navigation due to the “brain shift” effect. We conducted this study to evaluate the efficacy and safety of intraoperative magnetic resonance image (iMRI)-assisted neuro-port surgery for the resection of cerebral intraparenchymal cavernous malformation.

Methods

Between April 2016 and December 2017, 54 consecutive patients with intraparenchymal cerebral cavernous malformation who get surgical treatment in our hospital were enrolled into this study. Twenty-one patients were treated using iMRI-assisted neuro-port surgery (experiment group), and 33 patients underwent treatment by conventional microsurgery (control group). The iMRI was used in all cases for the compensation of the “brain shift” effect and keeping the navigation system up-to-date. The surgical resection rate, the total operation time, and the preoperative and postoperative Karnofsky Performance Status (KPS) scores were determined to evaluate the operative procedures.

Results

There were no significant differences between the two groups in mean age, gender ratio, and volume of lesions (P > 0.05). For the experiment group, the average duration of the procedure was 188.8 min with total resection of the lesions achieved in all 21 cases. For the control group, the average duration of the procedure was 238.2 min with total resection of the lesions achieved in 25 of 33 cases. The differences in the average duration of the procedure and the number of totally resected lesions between the two groups were statistically significant (P < 0.05). Regarding postoperative neurological function, postoperative KPS scores for the experiment group were significantly higher than those of the control group (P = 0.018).

Conclusion

Our results show that iMRI-assisted neuro-port surgery is helpful for intraparenchymal cerebral cavernous malformation surgery. The method provides high accuracy and efficiency for lesion targeting and permits excellent anatomic orientation. With the assistance of iMRI technology, we achieved a higher resection rate and a lower incidence of postoperative neurological deficits. Additionally, iMRI is helpful for the compensation of the “brain shift” effect, and it can update the navigation system.

Electronic supplementary material

The online version of this article (10.1186/s41016-019-0171-x) contains supplementary material, which is available to authorized users.

Stereotactic laser interstitial thermal therapy for epilepsy associated with solitary and multiple cerebral cavernous malformations

OBJECTIVE

The authors sought to perform a preliminary assessment of the safety and effectiveness of stereotactic laser interstitial thermal therapy (LITT) for patients with cerebral cavernous malformation (CCM)–related epilepsy.

METHODS

The authors retrospectively analyzed 6 patients with CCM-related epilepsy who underwent LITT. Pre-, intra-, and postoperative brain MRI studies were used to characterize preoperative CCM volume, ablation volume, and postablation hemosiderin volume. Clinical outcomes were assessed postoperatively during clinic follow-up visits or phone interviews.

RESULTS

LITT was performed in 7 CCMs in 6 patients. Two patients had familial CCM disease with multifocal lesions. Four treated CCMs were extratemporal, and 3 were in or near the visual pathways. The median follow-up was 25 (range 12–39) months. Five of 6 (83%) patients achieved seizure freedom (Engel I classification), of whom 4 (67%) were Engel IA and 1 was Engel IC after a single seizure on postoperative day 4. The remaining patient had rare seizures (Engel II). One patient had a nondisabling visual field deficit. There were no hemorrhagic complications. All patients were discharged within 24 hours postablation. MRI 3–11 months after ablation demonstrated expected focal necrosis and trace hemosiderin-related T2 hypointensity measuring 9%–44% (median 24%) of the original lesion volume, with significant (p = 0.04) volume reduction.

CONCLUSIONS

LITT is a minimally invasive option for treating CCM-related epilepsy with seizure outcomes comparable to those achieved with open lesionectomy. The precision of LITT allows for the obliteration of eloquent, deep, small, and multifocal lesions with low complication rates, minimal postoperative discomfort, and short hospital stays. In this study the feasibility and benefits of this method were demonstrated in 2 patients with multifocal lesions.

Surgically treated intracranial supratentorial calcifying pseudoneoplasms of the neuraxis (CAPNON) with drug-resistant left temporal lobe epilepsy: A case report and review of the literature

Calcifying pseudoneoplasms of the neuraxis (CAPNON) are rare pathological lesions that can present anywhere in the central nervous system. Symptoms vary depending on the location, though they often include seizures, especially in intracranial and supratentorial lesions. A case of intracranial supratentorial CAPNON presenting with drug-resistant left temporal lobe epilepsy is reported. The patient had a history of drug-resistant focal seizures for over 36 years. The lesion was located in the left mesial temporal lobe, but hippocampal sclerosis and hippocampal invasion were not apparent. The lesion was removed without hippocampectomy, and the patient has been seizure-free for one year.

Label-free imaging of hemoglobin degradation and hemosiderin formation in brain tissues with femtosecond pump-probe microscopy

The degradation of hemoglobin in brain tissues results in the deposition of hemosiderin, which is a major form of iron-storage protein and closely related to neurological disorders such as epilepsy. Optical detection of hemosiderin is vitally important yet challenging for the understanding of disease mechanisms, as well as improving surgical resection of brain lesions. Here, we provide the first label-free microscopy study of sensitive hemosiderin detection in both an animal model and human brain tissues. Methods: We applied spectrally and temporally resolved femtosecond pump-probe microscopy, including transient absorption (TA) and stimulated Raman scattering (SRS) techniques, to differentiate hemoglobin and hemosiderin in brain tissues. The label-free imaging results were compared with Perls' staining to evaluate our method for hemosiderin detection. Results: Significant differences between hemoglobin and hemosiderin transient spectra were discovered. While a strong ground-state bleaching feature of hemoglobin appears in the near-infrared region, hemosiderin demonstrates pure excited-state absorption dynamics, which could be explained by our proposed kinetic model. Furthermore, simultaneous imaging of hemoglobin and hemosiderin can be rapidly achieved in both an intracerebral hemorrhage (ICH) rat model and human brain surgical specimens, with perfect correlation with Perls' staining. Conclusion: Our results suggest that rapid, label-free detection of hemosiderin in brain tissues could be realized by femtosecond pump-probe microscopy. Our method holds great potential in providing a new tool for intraoperative detection of hemosiderin during brain surgeries.

Effectiveness of deferoxamine on ferric chloride-induced epilepsy in rats

Iron overload has been regarded as a common cause for refractory epilepsies in patients after hemorrhagic strokes. This study is to examine the potential epilepsy control effect of deferoxamine (DFO), an iron chelator, on a ferric chloride-induced epilepsy rat model. Twenty four rats were divided into 4 groups: group I is blank control group, group II is sham group with intracortical injection of saline, group III is epilepsy group with intracortical injection of iron and saline treatment, group IV is treatment group with intracortical injection of iron and DFO treatment. For the DFO intervention group, a daily dose of 100mg/kg DFO via peritoneal injection was applied for 14days. Outcomes were evaluated by behavioral study, electroencephalography (EEG), magnetic resonance imaging (MRI) scan and tissue analysis. Epilepsies according to behavioral observations and EEG analysis were significantly suppressed after intervention of DFO. Reduction of iron content in the brain cortex was proved by diminished low signal area on T2-MRI images (p=0.006) and tissue analysis (p<0.001), simultaneously the superoxide dismutase (SOD) activity increased (p<0.001). Western blot analysis demonstrated the decreasing of local transferrin after DFO treatment. DFO is efficient at Fe clearance, thus helpful in epilepsy control. This finding implies potential therapeutic value of DFO in patients with refractory epilepsy after hemorrhagic stroke.

Accuracy of SWI sequences compared to T2*-weighted gradient echo sequences in the detection of cerebral cavernous malformations in the familial form

PURPOSE

The purpose of this study was to assess the accuracy of susceptibility-weighted imaging (SWI), compared with T2*-weighted gradient echo (GRE) imaging in assessing cerebral cavernous malformations.

MATERIALS AND METHODS

We retrospectively evaluated 21 patients with a familial form of cavernous malformation. Magnetic resonance (MR) protocol included non-enhanced and contrast-enhanced fast-spin echo (FSE) T1-weighted sequences, FSE T2-weighted sequences, fluid-attenuated inversion-recovery (FLAIR), GRE T2*-weighted and SWI sequences. Images were reviewed in consensus by two expert neuroradiologists to assess the location, number, size and conspicuity of the lesions on T2*-weighted GRE and SWI sequences. Statistical differences in the number, size and conspicuity of the lesions seen on the SWI images and the T2*-weighted GRE images were assessed with the nonparametric Wilcoxon signed rank test.

RESULTS

The number of cavernous malformations was significantly higher (p < .001) on the SWI images (n = 152) than on T2*-weighted GRE images (n = 56). Lesion size was significantly higher (p < .001) on SWI images (mean: 0.4 cm, SD ± 0.55) than on T2*-weighted GRE sequences (mean: 0.2 cm, SD ± 0.51) and the differences were statistically significant (p < .001). Lesion conspicuity was significant higher (p < .001) on SWI than on T2*-weighted GRE images. In one patient who underwent a 2-month follow-up for the onset of neurologic symptoms related to cerebral hemorrhage, a cerebral hematoma was identified at the site of a cerebral cavernous malformation that was demonstrated only on the SWI images in the previous MR examination.

CONCLUSIONS

The SWI sequence, being more sensitive to substances which distort the local magnetic field than the GRE T2*W sequence, showed a higher sensitivity in identifying cerebral cavernous malformations. Thus, routine clinical neuroimaging protocol should contain SWI sequences to evaluate patients with (or suspected) cerebral cavernous malformations.

The Role of Hemosiderin Excision in Seizure Outcome in Cerebral Cavernous Malformation Surgery: A Systematic Review and Meta-Analysis

Background and Purpose

Whether the excision of hemosiderin surrounding cerebral cavernous malformations (CCMs) is necessary to achieve a seizure-free result has been the subject of debate. Here, we report a systematic review of related literature up to Jan 1, 2015 including 594 patients to assess the effect of hemosiderin excision on seizure outcome in patients with CCMs by meta-analysis.

Methods

Ten studies comparing extended hemosiderin excision with only lesion resection were identified by searching the English-language literature. Meta-analyses, subgroup analyses and sensitivity analysis were conducted to determine the association between hemosiderin excision and seizure outcome after surgery.

Results

Seizure outcome was significantly improved in the patients who underwent an extended excision of the surrounding hemosiderin (OR, 0.62; 95% CI: 0.42–0.91; P = 0.01). In subgroup analysis, studies from Asia (OR, 0.42; 95% CI: 0.25–0.71; P = 0.001), male-majority (female ratio < 50%) studies (OR, 0.56; 95% CI: 0.33–0.96; P = 0.04), low occurrence rate of multiple CCMs (OR, 0.37; 95% CI: 0.20–0.71; P = 0.003), cohort studies (OR, 0.44; 95% CI: 0.28–0.68; P = 0.78), longer duration of seizure symptoms (> 1 year) before surgery (OR, 0.43; 95% CI: 0.22–0.84; P = 0.01), lesion diameter > 2 cm (OR, 0.41; 95% CI: 0.19–0.87; P = 0.02) and short-term (< 3 years) follow-up (OR, 0.48; 95% CI: 0.29–0.80; P = 0.005) tended to correlate with a significantly favorable outcome.

Conclusion

Patients who underwent extended surrounding hemosiderin excision could exhibit significantly improved seizure outcomes compared to patients without hemosiderin excision. However, further well-designed prospective multiple-center RCT studies are still needed.

Paraventricular or centrum ovale cavernous hemangioma involving the pyramidal tract in children: intraoperative MRI and functional neuronavigation-guided resection

OBJECTIVES

In this study, we investigated whether visualization of the pyramidal tract and intraoperative MRI combined with functional navigation was helpful in the resection of paraventricular or centrum ovale cavernous hemangioma in children.

METHODS

Twelve patients with cavernous hemangioma located in the paraventricular area or in the centrum ovale adjacent to the pyramidal tract were prospectively enrolled in the study. The pyramidal tract of all patients was visualized preoperatively, and all patients underwent tailored craniotomy with white matter trajectory to resect the lesion, with the help of intraoperative MRI and microscope-based functional neuronavigation.

RESULTS

In our study, of the total of 12 patients (nine males and three females), five patients had lesions on the left side, and seven had lesions located in the right hemisphere. The lesion volume varied from 0.2 to 11.45 cm(3). In seven cases, the distance of the lesion from the pyramidal tract was 0-5 mm (the 0-5 mm group), and five cases were in the 5-10 mm group. The 3D visualization of the lesion and the pyramidal tract helped the surgeon design the optimal surgical approach and trajectory. Intraoperative functional neuronavigation allowed them to obtain access to the lesion accurately and precisely. All lesions had been removed totally at the end of the surgery. Compared with the preoperative level, muscle strength at 2 weeks had decreased in six cases, was unchanged in four cases, and improved in two cases; at 3 months, it was improved in five cases, unchanged in six cases, and decreased in one case.

CONCLUSIONS

Pyramidal tract visualization and intraoperative MRI combined with functional neuronavigation can aid in safe removal of paraventricular or centrum ovale cavernous hemangioma involving the pyramidal tract.

Co-occurrence of a cerebral cavernous malformation and an orbital cavernous hemangioma in a patient with seizures and visual symptoms: Rare crossroads for vascular malformations

Background:

Cerebral cavernous malformations (CCMs) are angiographically occult vascular malformations of the central nervous system. As a result of hemorrhage and mass effect, patients may present with focal neurologic deficits, seizures, and other symptoms necessitating treatment. Once symptomatic, most often from hemorrhage, CCMs are treated with microsurgical resection. Orbital cavernous hemangiomas (OCHs) are similar but distinct vascular malformations that present within the orbital cavity. Even though CCMs and OCHs are both marked by dilated endothelial-lined vascular channels, they are infrequently seen in the same patient.

Case Description:

We provide a brief overview of the two related pathologies in the context of a patient presenting to our care with concomitant lesions, which were both resected in full without complication.

Conclusion:

This is the first known report that describes a case of concomitant CCM and OCH and explores the origins of two pathologies that are rarely encountered together in neurosurgical practice. Recognition of disparate symptomatologies is important for properly managing these patients.

Zebrafish models of cerebrovascular disease

Perturbations in cerebral blood flow and abnormalities in blood vessel structure are the hallmarks of cerebrovascular disease. While there are many genetic and environmental factors that affect these entities through a heterogeneous group of disease processes, the ultimate final pathologic insult in humans is defined as a stroke, or damage to brain parenchyma. In the case of ischemic stroke, blood fails to reach its target destination whereas in hemorrhagic stroke, extravasation of blood occurs outside of the blood vessel lumen, resulting in direct damage to brain parenchyma. As these acute events can be neurologically devastating, if not fatal, development of novel therapeutics are urgently needed. The zebrafish (Danio rerio) is an attractive model for the study of cerebrovascular disease because of its morphological and physiological similarity to human cerebral vasculature, its ability to be genetically manipulated, and its fecundity allowing for large-scale, phenotype-based screens.