Cognitive performance in patients with cerebral arteriovenous malformation

MEK signaling represents a viable therapeutic vulnerability of KRAS-driven somatic brain arteriovenous malformations

Brain arteriovenous malformations (bAVMs) are direct connections between arteries and veins that remodel into a complex nidus susceptible to rupture and hemorrhage. Most sporadic bAVMs feature somatic activating mutations within KRAS, and endothelial-specific expression of the constitutively active variant KRASG12D models sporadic bAVM in mice. By leveraging 3D-based micro-CT imaging, we demonstrate that KRASG12D-driven bAVMs arise in stereotypical anatomical locations within the murine brain, which coincide with high endogenous Kras expression. We extend these analyses to show that a distinct variant, KRASG12C, also generates bAVMs in predictable locations. Analysis of 15,000 human patients revealed that, similar to murine models, bAVMs preferentially occur in distinct regions of the adult brain. Furthermore, bAVM location correlates with hemorrhagic frequency. Quantification of 3D imaging revealed that G12D and G12C alter vessel density, tortuosity, and diameter within the mouse brain. Notably, aged G12D mice feature increased lethality, as well as impaired cognition and motor function. Critically, we show that pharmacological blockade of the downstream kinase, MEK, after lesion formation ameliorates KRASG12D-driven changes in the murine cerebrovasculature and may also impede bAVM progression in human pediatric patients. Collectively, these data show that distinct KRAS variants drive bAVMs in similar patterns and suggest MEK inhibition represents a non-surgical alternative therapy for sporadic bAVM.

Considering Psychological and Cognitive Factors in Interventional Neuroradiology: A Systematic Literature Review

BACKGROUND

Interventional neuroradiology is a relatively recent discipline that diagnoses and treats cerebral vascular diseases. However, specific literature on cognitive and psychological domains of patients undergoing interventional neuroradiology procedures is limited.

PURPOSE

Our aim was to review the existent literature on cognitive and psychological domains in patients undergoing interventional neuroradiology procedures to raise clinicians' awareness of their mental status.

DATA SOURCES

Articles were searched in PubMed, EMBASE, and Scopus from 2000 to 2022 using terms such as "interventional neuroradiology," "psychology," and "cognition" according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines.

STUDY SELECTION

Of 1483 articles in English, 64 were included and analyzed. Twelve focused on psychological aspects; 52, on cognitive ones.

DATA ANALYSIS

Regarding psychological aspects, it appears that early psychological consultations and "nonpharmacologic" strategies can impact the anxiety and depression of patients undergoing endovascular procedures. Regarding cognitive aspects, it appears that endovascular treatment is safe and generates similar or even fewer cognitive deficits compared with analogous surgical procedures.

DATA SYNTHESIS

Among the 12 articles on psychological aspects, 6/12 were retrospective with one, while 6/12 were prospective. Among the 52 articles on cognitive aspects, 7/54 were retrospective, while 45/52 were prospective.

LIMITATIONS

The main limitation derives from the inhomogeneity of the cognitive and psychological assessment tools used in the articles included in our analysis.

CONCLUSIONS

Our review highlights the need to include cognitive and psychological assessments in clinical practice in case patients eligible for interventional neuroradiology procedures. In the future, much more research of and attention to cognitive and psychologic aspects of neurovascular disease is needed. Systematic incorporation of strategies and tools to access and address pre, peri-, and postprocedural psychological and cognitive components could have major benefits in patient satisfaction, recovery, and the success of endovascular practice.

Altered Brain Structural Networks in Patients with Brain Arteriovenous Malformations Located in Broca's Area

Focal brain lesions, such as stroke and tumors, can lead to remote structural alterations across the whole-brain networks. Brain arteriovenous malformations (AVMs), usually presumed to be congenital, often result in tissue degeneration and functional displacement of the perifocal areas, but it remains unclear whether AVMs may produce long-range effects upon the whole-brain white matter organization. In this study, we used diffusion tensor imaging and graph theory methods to investigate the alterations of brain structural networks in 14 patients with AVMs in the presumed Broca's area, compared to 27 normal controls. Weighted brain structural networks were constructed based on deterministic tractography. We compared the topological properties and network connectivity between patients and normal controls. Functional magnetic resonance imaging revealed contralateral reorganization of Broca's area in five (35.7%) patients. Compared to normal controls, the patients exhibited preserved small-worldness of brain structural networks. However, AVM patients exhibited significantly decreased global efficiency (p = 0.004) and clustering coefficient (p = 0.014), along with decreased corresponding nodal properties in some remote brain regions (p < 0.05, family-wise error corrected). Furthermore, structural connectivity was reduced in the right perisylvian regions but enhanced in the perifocal areas (p < 0.05). The vulnerability of the left supramarginal gyrus was significantly increased (p = 0.039, corrected), and the bilateral putamina were added as hubs in the AVM patients. These alterations provide evidence for the long-range effects of AVMs on brain white matter networks. Our preliminary findings contribute extra insights into the understanding of brain plasticity and pathological state in patients with AVMs.