Fontanella, Marco Maria

BACKGROUND: Arteriovenous malformation (AVM) recurrence after complete surgical resection is a rare but significant clinical event. The underlying mechanisms and factors that predict recurrence remain incompletely defined. METHODS: We conducted a systematic review and meta-analysis in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 guidelines. We included case series reporting on AVM recurrence following an angiographically documented complete resection. Data on initial clinical presentation, patients' demographics, AVM features, and patterns of recurrence were extracted and analyzed. RESULTS: We included 15 studies with a total of 1287 patients in our meta-analysis. The overall estimated recurrence rate was 5.4%. Hemorrhagic presentation appeared as a major predictor: in fact, 94% of recurrences occurred in patients with a prior rupture, corresponding to a 7.3% (95% CI, 0.049–0.098) recurrence rate within this high-risk subgroup. Ruptured AVMs were associated with 4-fold higher odds of recurrence compared with unruptured AVMs (odds ratio, 4.072 [95% CI, 1.492–11.113]). Younger age was also found to be a key factor, with pediatric patients accounting for 89% of all recurrences. Deep venous drainage was associated with a nearly 5-fold increased risk of recurrence (odds ratio, 4.96 [95% CI, 1.801–13.662]), while eloquent brain location was not found as a statistically significant predictor. The mean time to recurrence was 39.6 (95% CI, 27.80–51.41) months, while follow-ups varied among patients. CONCLUSIONS: Hemorrhagic presentation, younger age, and deep venous drainage demonstrated to be significant predictors of AVM recurrence after complete resection, whereas vascular aging appears protective. In older individuals, proangiogenic mediators (VEGF [vascular endothelial growth factor], HIF-1 [hypoxia-inducible factor-1] α, eNOS [endothelial nitric oxide synthase], and MMPs [matrix metalloproteinases]) are downregulated via aging-related pathways, limiting neovascularization and making recurrence biologically less likely. These findings underscore the need for prolonged, risk-adapted surveillance protocols, particularly for high-risk pediatric patients who present with hemorrhage.

Background/Objectives: Tuberculum sellae meningiomas (TSMs) constitute 5–10% of intracranial meningiomas, often causing visual impairment. Traditional microsurgical transcranial approaches (MTAs) have been effective, but the emergence of innovative surgical trajectories, such as endoscopic endonasal approaches (EEAs), has sparked debate. While EEAs offer advantages like reduced brain retraction, they are linked to higher cerebrospinal fluid leak (CSF leak) risk. This meta-analysis aims to comprehensively compare the efficacy and safety of EEAs and MTAs for the resection of TSMs, offering insights into their respective outcomes and complications. Methods: A comprehensive literature review of the databases PubMed, Ovid MEDLINE, and Ovid EMBASE was conducted for articles published on TSMs treated with either EEA or MTA until 2024. The systematic review was performed according to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guidelines. Meta-analysis was performed to estimate pooled event rates and assess heterogeneity. Fixed- and random-effects were used to assess 95% confidential intervals (CIs) of presenting symptoms, outcomes, and complications. Results: A total of 291 papers were initially identified, of which 18 studies spanning from 2000 to 2024 met the inclusion criteria. The exclusion of 180 articles was due to reasons such as irrelevance, non-reporting of selected results, systematic literature review or meta-analysis, and a lack of details on method/results. The 18 studies comprised a total sample of 1093 patients: 444 patients who underwent EEAs and 649 patients who underwent MTAs for TSMs. Gross total resection (GTR) rates ranged from 80.9% for EEAs to 79.8% for MTAs. The rate of visual improvement was 86.6% in the EEA group and 65.4% in the MTA group. The recurrence rate in the EEA group was 6.9%, while it was 5.1% in MTA group. The postoperative complications analyzed were CSF leak, infections, dysosmia, intracranial hemorrhage (ICH), and endocrine disorders. The rate of CSF leak was 9.8% in the EEA group and 2.1% in MTA group. The rate of infections in the EEA group was 5.7%, while it was 3.7% in the MTA group. The rate of dysosmia ranged from 10.3% for MTAs to 12.9% for EEAs. The rate of ICH in the EEA group was 0.9%, while that in the MTA group was 3.8%. The rate of endocrine disorders in the EEA group was 10.8%, while that in the MTA group was 10.2%. No significant difference was detected in the rate of GTR between the EEA and MTA groups (OR 1.15, 95% CI 0.7–0.95; p = 0.53), while a significant benefit in visual outcomes was shown in EEAs (OR 3.54, 95% CI 2.2–5.72; p < 0.01). There was no significant variation in the recurrence rate between EEA and MTA groups (OR 0.92, 95% CI 0.19–4.46; p = 0.89). While a considerably increased chance of CSF leak from EEAs was shown (OR 4.47, 95% CI 2.52–7.92; p < 0.01), no significant difference between EEA and MTA groups was detected in the rate of infections (OR 1.92, 95% CI 0.73–5.06; p = 0.15), the rate of dysosmia (OR 1.25, 95% CI 0.31–4.99; p = 0.71), the rate of ICH (OR 0.61, 95% CI 0.20–1.87; p = 0.33), and the rate of endocrine disorders (OR 1.16, 95% CI 0.69–1.95; p = 0.53). Conclusions: This meta-analysis suggests that both EEAs and MTAs are viable options for TSM resection, with distinct advantages and drawbacks. The EEAs demonstrate superior visual outcomes in selected cases while GTR and recurrence rates support the overall effectiveness of MTAs and EEAs. Endoscopic endonasal approaches had a higher chance of CSF leaks, but there are no appreciable variations in other complications. These results provide additional insights regarding patient outcomes in the intricate clinical setting of TSMs.

Arterial spin labeling (ASL) has emerged as a promising noninvasive tool for the evaluation of both pediatric and adult arteriovenous malformations (AVMs). This paper reviews the advantages and challenges associated with the use of ASL in AVM assessment. An assessment of the diagnostic workup of AVMs and their variants in both adult and pediatric populations is proposed. Evaluation after treatments, whether endovascular or microsurgical, was similarly examined. ASL, with its endogenous tracer and favorable safety profile, offers functional assessment and arterial feeder identification. ASL has demonstrated strong performance in identifying feeder arteries and detecting arteriovenous shunting, although some studies report inferior performance compared with digital subtraction angiography (DSA) in delineating venous drainage. Challenges include uncertainties in sensitivity for specific AVM features. Detecting AVMs in challenging locations, such as the apical cranial convexity, is further complicated, demanding careful consideration due to the risk of underestimating total blood flow. Navigating these challenges, ASL provides a noninvasive avenue with undeniable merits, but a balanced approach considering its limitations is crucial. Larger-scale prospective studies are needed to comprehensively evaluate the diagnostic performance of ASL in AVM assessment.

Purpose: To better define the overall performance of the current radiomics-based models for the discrimination of pediatric posterior fossa tumors. Methods: A comprehensive literature search of the databases PubMed, Ovid MEDLINE, Ovid EMBASE, Web of Science, and Scopus was designed and conducted by an experienced librarian. We estimated overall sensitivity (SEN) and specificity (SPE). Event rates were pooled across studies using a random-effects meta-analysis, and the χ2 test was performed to assess the heterogeneity. Results: Overall SEN and SPE for differentiation between MB, PA, and EP were found to be promising, with SEN values of 93% (95% CI = 0.88–0.96), 83% (95% CI = 0.66–0.93), and 85% (95% CI = 0.71–0.93), and corresponding SPE values of 87% (95% CI = 0.82–0.90), 95% (95% CI = 0.90–0.98) and 90% (95% CI = 0.84–0.94), respectively. For MB, there is a better trend for LR classifiers, while textural features are the most used and the best performing (ACC 96%). As for PA and EP, a synergistic employment of LR and NN classifiers, accompanied by geometrical or morphological features, demonstrated superior performance (ACC 94% and 96%, respectively). Conclusions: The diagnostic performance is high, making radiomics a helpful method to discriminate these tumor types. In the forthcoming years, we expect even more precise models.

Recently, advances in molecular biology and bioinformatics have allowed a more thorough understanding of tumorigenesis in aggressive PitNETs (pituitary neuroendocrine tumors) through the identification of specific essential genes, crucial molecular pathways, regulators, and effects of the tumoral microenvironment. Target therapies have been developed to cure oncology patients refractory to traditional treatments, introducing the concept of precision medicine. Preliminary data on PitNETs are derived from preclinical studies conducted on cell cultures, animal models, and a few case reports or small case series. This study comprehensively reviews the principal pathways involved in aggressive PitNETs, describing the potential target therapies. A search was conducted on Pubmed, Scopus, and Web of Science for English papers published between 1 January 2004, and 15 June 2023. 254 were selected, and the topics related to aggressive PitNETs were recorded and discussed in detail: epigenetic aspects, membrane proteins and receptors, metalloprotease, molecular pathways, PPRK, and the immune microenvironment. A comprehensive comprehension of the molecular mechanisms linked to PitNETs’ aggressiveness and invasiveness is crucial. Despite promising preliminary findings, additional research and clinical trials are necessary to confirm the indications and effectiveness of target therapies for PitNETs.