Treatment of Brain Arteriovenous Malformations.

Brain arteriovenous malformations (AVMs) are a rare entity of vascular anomalies, characteristic of anatomical shunting where arterial blood directly flows into the venous circulation. The main aim of the active treatment policy of brain AVMs is the prevention of haemorrhage. There are well-established treatment strategies that continually improve in their safety and efficacy, primarily due to the advances in imaging modalities, targeted and novel techniques, the development of alternative treatment approaches, and even better experience with the disease itself. There are interesting imaging novelties that may be prospectively applicable in the decision-making and planning of the most effective treatment approach for individual patients with intracranial AVM. Surgery is often considered the first-line treatment; however, each patient should be evaluated individually, and the risks of the active treatment policy should not overcome the benefits of the spontaneous natural history of the disease. All treatment modalities, i.e., surgery, radiosurgery, endovascular embolization, and observation, are justified but need to be meticulously selected for each individual patient in order to deliver the best treatment outcome. This chapter deals with historical and currently applied dogmas, followed by introductions of advances in each available treatment modality of AVM management.

Comparison of decline in different cognitive domain in patients with normal pressure hydrocephalus.

We sought to describe the cognitive profile of patients with Idiopathic Normal Pressure Hydrocephalus (iNPH) using a comprehensive neuropsychological battery. Based on age and education correlated norms, we aimed to compare performance in each measured cognitive domain: executive functions (EFs), verbal memory (VM), non-verbal memory (nVM), visuoconstructional abilities (VA) and attention/psychomotor speed (A/PS). Patients diagnosed with iNPH underwent comprehensive neuropsychological evaluation before shunting. Their performance was compared to the age and education correlated norms. Correlation of different cognitive domains in iNPH profile was performed. A total of 53 iNPH patients (73.21 ± 5.48 years) were included in the study. All of the measured cognitive domains were significantly damaged. The most affected domains were EFs and VM (p<0.001 and p<0.001, respectively). A/PS domain was affected milder than EFs and VM (p<0.001). The least affected domains were nVM (p<0.001) and VA (p<0.001). Patients with iNPH are affected in all cognitive domains and the cognitive decline is uneven across these domains. The impairment of memory was shown to depend on the presented material. VM was shown to be much more severely affected than nVM and along with VM, EFs were shown to be the most affected. A/PS speed was shown to be less affected than VM and EFs and the least affected domains were nVM and VA.

Clinical and molecular study of radiation-induced gliomas.

In this study, we provide a comprehensive clinical and molecular biological characterization of radiation-induced gliomas (RIG), including a risk assessment for developing gliomas. A cohort of 12 patients who developed RIG 9.5 years (3-31 years) after previous cranial radiotherapy for brain tumors or T-cell acute lymphoblastic leukemia was established. The derived risk of RIG development based on our consecutive cohort of 371 irradiated patients was 1.6% at 10 years and 3.02% at 15 years. Patients with RIG glioma had a dismal prognosis with a median survival of 7.3 months. We described radiology features that might indicate the suspicion of RIG rather than the primary tumor recurrence. Typical molecular features identified by molecular biology examination included the absence of Histon3 mutation, methylation profile of pedHGG-RTK1 and the presence of recurrent PDGFRA amplification and CDKN2A/B deletion. Of the two long-term surviving patients, one had gliomatosis cerebri, and the other had pleomorphic xanthoastrocytoma with BRAF V600E mutation. In summary, our experience highlights the need for tissue diagnostics to allow detailed molecular biological characterization of the tumor, differentiation of the secondary tumor from the recurrence of the primary disease and potentially finding a therapeutic target.

The Enhanced Recovery After Surgery protocol for the surgical management of craniosynostosis: Lausanne experience.

OBJECTIVE: Over the past decade, the Enhanced Recovery After Surgery (ERAS) program has demonstrated its effectiveness and efficiency in improving postoperative care and enhancing recovery across various surgical fields. Preliminary results of ERAS protocol implementation in craniosynostosis surgery are presented. METHODS: An ERAS protocol was developed and implemented for cranial pediatric neurosurgery, focusing on craniosynostosis repair. The study incorporated a pre-ERAS group consisting of a consecutive series of patients who underwent craniosynostosis repair surgery prior to the implementation of the ERAS protocol; the results were compared with a consecutive group of patients who had been prospectively collected since the introduction of the ERAS for craniosynostosis protocol. The safety, feasibility, and efficiency of the ERAS protocol in pediatric neurosurgery was evaluated, through the collection of clinical data from the pre-, intra-, and postoperative phase. Surgery-related complications were evaluated according to the Clavien-Dindo classification. Costs of the stays were obtained using a microcosting approach. RESULTS: A total of 35 pre-ERAS patients and 10 ERAS patients were included. Scaphocephaly was the most common pathology in both groups. The overall compliance with the pre-, intra-, and postoperative criteria significantly increased-from 35.5%, 64.4%, and 54.7%, respectively, in each phase to 94%, 90%, and 84% (p < 0.001). The authors noticed a reduction in the average opioid dose used per patient in the ERAS group (p = 0.004), and they observed a trend toward a decreased mean length of stay from 5.2 days in the pre-ERAS group to 4.6 days in the ERAS group, without an increase of the rate of readmission within 30 days of surgery. The rate of complications decreased but this difference was not statistically significant. The hospital costs lowered significantly: from 21,958 Confederatio Helvetica Francs (CHF) in the pre-ERAS group to 18,936 CHF in the ERAS group (p = 0.02). CONCLUSIONS: The ERAS protocol represents a safe and cost-effective tool for the perioperative management of craniosynostosis. It showed its positive impact on the analgesia provided and on the reduction of in-hospital costs for these patients. ERAS protocols may thus be interesting options in the pediatric neurosurgical field.

Application of diffusion tensor imaging of the facial nerve in preoperative planning for large vestibular schwannoma: a systematic review.

The accurate identification and preservation of the facial nerve (FN) during vestibular schwannoma (VS) surgery is crucial for maintaining facial function. Investigating the application of diffusion tensor imaging (DTI) in preoperative planning for large VS surgery is provided. PubMed, Cochrane Library, Science Direct, ISI Web of Science, Embase, and additional sources were searched to identify cohort studies about the preoperative DTI usage for the FN tracking before large VS (≥ 2.5 cm) surgery published between 1990 and 2023. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed; the Newcastle-Ottawa Scale was used to assess the risk of bias and to evaluate limitations based on selection/outcome biases. A total of 8 publications yielding 149 VS (mean size 3.66 ± 0.81 cm) were included. Surgical concordance with preoperative DTI FN tracking was 91.67% (range 85-100%). Overall DTI reliability was 88.89% (range 81.81-95.83%). Larger tumor size predicted either DTI inaccurate finding or complete DTI failure (p = 0.001). VS size above > 3.5 cm was associated with a higher risk of DTI failure (p = 0.022), with a higher risk of inaccurate DTI finding preoperatively (p = 0.033), and with a higher House-Brackman score postoperatively (p = 0.007). Application of DTI in larger VS surgery is a valuable FN identification along with electrophysiological monitoring and neuronavigation, therefore also in its preservation and in lowering risk of complications. DTI represents a valuable adjunct to electrophysiological monitoring and neuronavigation in FN identification, applicable not only for smaller, but also larger VS.

Predictors of postoperative complications and functional outcomes in pediatric patients with surgically treated fourth ventricle tumors.

BACKGROUND: Tumors of the fourth ventricle are frequently treated pathologies in pediatric neurosurgery. Data regarding predictors for permanent neurological deficits, long-term functional outcomes, cerebellar mutism (CM), the extent of resection (EOR), and oncological outcomes are scarce. We attempt to contribute to this topic with an analysis of our institutional cohort. METHODS: A retrospective single-center study of patients aged ≤ 19 years who underwent primary surgical resection of a fourth ventricular tumor over a 15-year period (2006-2021). Predictors analyzed included age, gender, surgical approach, anatomical pattern, tumor grade, EOR, tumor volume, and others as appropriate. RESULTS: One hundred six patients were included (64 males, mean age 7.3 years). The rate of permanent neurological deficit was 24.2%; lateral tumor extension (p = 0.036) and tumor volume greater than 38 cm3 (p = 0.020) were significant predictors. The presence of a deficit was the only significant predictor of reduced (less than 90) Lansky score (p = 0.005). CM occurred in 20.8% of patients and was influenced by medulloblastoma histology (p = 0.011), lateral tumor extension (p = 0.017), and male gender (p = 0.021). No significant difference between the transvermian and telovelar approach in the development of CM was detected (p = 0.478). No significant predictor was found for the EOR. EOR was not found to be a significant predictor of overall survival for both low-grade and high-grade tumors; however, gross total resection (GTR) was protective against tumor recurrence compared to near-total or subtotal resection (p < 0.001). In addition, survival was found to be better in older patients (≥ 7.0 years, p = 0.019). CONCLUSION: The overall rate of postoperative complications remains high due to the eloquent localization. Older patients (> 7 years) have been found to have better outcomes and prognosis. Achieving GTR whenever feasible and safe has been shown to be critical for tumor recurrence. CM was more common in patients with medulloblastoma and in patients with tumors extending through the foramen of Luschka. The telovelar approach uses a safe and anatomically sparing corridor; however, it has not been associated with a lower incidence of CM and neurological sequelae in our series, showing that each case should be assessed on an individual basis.

Diffusion tensor imaging helps identify shunt-responsive normal pressure hydrocephalus patients among probable iNPH cohort.

The aim of this study was to investigate whether white matter changes as measured by diffusion tensor imaging (DTI) can help differentiate shunt-responsive idiopathic normal pressure hydrocephalus (iNPH) patients from patients with other causes of gait disturbances and/or cognitive decline with ventriculomegaly whose clinical symptoms do not improve significantly after cerebrospinal fluid derivation (non-iNPH). Between 2017 and 2022, 85 patients with probable iNPH underwent prospective preoperative magnetic resonance imaging (MRI) and comprehensive clinical workup. Patients with clinical symptoms of iNPH, positive result on lumbar infusion test, and gait improvement after 120-h lumbar drainage were diagnosed with iNPH and underwent shunt-placement surgery. Fractional anisotropy (FA) and mean diffusivity (MD) values for individual regions of interest were extracted from preoperative MRI, using the TBSS pipeline of FSL toolkit. These FA and MD values were then compared to results of clinical workup and established diagnosis of iNPH. An identical MRI protocol was performed on 13 age- and sex-matched healthy volunteers. Statistically significant differences in FA values of several white matter structures were found not only between iNPH patients and healthy controls but also between iNPH and non-iNPH patients. ROI that showed best diagnostic ability when differentiating iNPH among probable iNPH cohort was uncinate fasciculus, with AUC of 0.74 (p < 0.001). DTI methods of white matter analysis using standardised methods of ROI extraction can help in differentiation of iNPH patients not only from healthy patients but also from patients with other causes of gait disturbances with cognitive decline and ventriculomegaly.

Evaluation of the growth rates and related prognostic factors in radiation-induced meningiomas.

PURPOSE: Literature dedicated to growth patterns and growth rate influencing factors of radiation-induced meningiomas (RIMs) is limited. To deliver new insights into the topic, a volumetric growth analysis of RIMs was performed. METHODS: This single-center, retrospective cohort study included patients diagnosed with intracranial meningioma who received radiation treatment at least > 5 years before the RIM diagnosis. Volumetric analysis of individual RIMs was performed using 3D volumetry at the time of RIM diagnosis and during follow-up. RIM growth was determined by calculating absolute (AGR), and relative (RGR) growth rates. Prognostic factors associated with RIM growth were evaluated. RESULTS: A total of 26 patients with 33 meningiomas were enrolled in the study and radiologically/clinically followed up during a median duration of 5.6 years (IQR 3.9-8.8 years). Median AGR was 0.19 cm3 per year and the median RGR was 34.5% per year. Surgically managed RIMs were more likely fast-growing compared to observed ones based on the AGR (p < 0.002). The recurrence rate after total resection was 14.3%. Younger age at RIM diagnosis was associated with higher tumor growth (RGR ≥ 30%, p = 0.040). A significant correlation was found between the length of latency period and the RGR (p = 0.005). CONCLUSION: To diagnose RIM as early as possible comprehensive MRI surveillance is required. Younger patients with shorter latency periods may profit from shortened MRI intervals, with further management being dependent on the growth rate and eventual symptomatology.

Partial medial clinoidectomy with optic canal roof drilling for clipping of ophthalmic artery aneurysms: how I do it.

BACKGROUND: Clipping of ophthalmic artery (OA) aneurysms present one of the treatment strategies for long-term disease management. Existing surgical techniques primarily require extra/intradural removal of the anterior clinoid process, carrying a higher risk of infection, damage to surrounding structures or technical complications. METHODS: We present the technique of minimally invasive partial medial clinoidectomy with the unroofing of the optic canal for surgical clipping of OA aneurysms, and besides its pros and cons, we also discuss proper technical indications. CONCLUSION: The partial medial clinoidectomy improves manoeuvrability around the paraclinoid region, provides better protection for adjacent structures and renders excellent treatment outcome.

Overview of cerebral cavernous malformations: comparison of treatment approaches.

OBJECTIVES: The comparison of treatment efficacy for cerebral cavernous malformations (CCMs) has not yet been well researched. DESIGN: PubMed, Cochrane Library, Science Direct, ISI Web of Science, Embase and additional sources were searched to identify cohort studies about the treatment of CCMs published between 1990 and 2020. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed; the Newcastle-Ottawa Scale was used to assess the risk of bias and to evaluate limitations based on selection/outcome biases. The cumulative incidences with 95% CIs were calculated using the random effects model. The models of Poisson distribution were applied to evaluate risk factors of poorer treatment outcome by calculating rate ratios within 100 person-years with 95% CIs. RESULTS: A total of 100 cohorts yielding 8994 patients treated for CCMs within 41 098 person-years of follow-up were analysed. The efficacy of ensuring the prevention of haemorrhage was 97% in surgical, 86% in radiosurgical and 77% in the conservative treatment. The lowest mortality (1%) was after radiosurgery, and the highest persistent morbidity (22%) was in natural history series. Deep-seated and brainstem CCMs were associated with higher bleeding rates. Lobar localisation was a protective factor in all analyses. Patients with history of previous haemorrhage were exposed to higher risk of rebleeding. Male gender was a protective factor associated with lower risk of post-treatment haemorrhage. CONCLUSIONS: Surgical resection of CCM is effective in ensuring the prevention of haemorrhage with acceptable morbidity and mortality, but conservative and radiosurgical management is a justified treatment alternative. Brainstem and deep-seated CCMs are predominantly associated with higher haemorrhage rates.