Study the local metabolic changes of aneurysms through microcatheter sampling.

Area of Science:

• Neuroscience
• Biochemistry
• Medical Diagnostics

Background:

• Intracranial aneurysms are a leading cause of non-traumatic subarachnoid hemorrhage.
• Understanding aneurysm metabolism is crucial for diagnosing and treating these conditions.
• Existing methods for analyzing aneurysm blood are limited by interpatient variability.

Purpose of the Study:

• To develop and validate a method for intra-operative blood sampling directly from intracranial aneurysms and feeding vessels.
• To characterize the unique plasma metabolite profiles within intracranial aneurysms.
• To identify metabolic markers associated with aneurysm characteristics and patient recovery.

Main Methods:

• Intra-operative collection of blood samples from aneurysm necks and proximal/distal vessels using microcatheters.
• Analysis of 39 plasma samples from 13 patients using untargeted liquid chromatography-mass spectrometry.
• Paired comparison of metabolite levels to control for interpatient variations.

Main Results:

• Upregulation of L-tyrosine and downregulation of phenylpyruvic acid, L-cystine, and L-ornithine were observed at the aneurysm neck.
• A significant decrease in arginine was noted in small internal carotid artery aneurysms.
• Lower levels of biliverdin, bilirubin, and coenzyme Q metabolites correlated with good recovery at 6 months.

Conclusions:

• The study presents a novel method for aneurysm blood sampling, enabling precise metabolic profiling.
• Identified metabolite differences suggest potential pathogenetic mechanisms in unruptured intracranial aneurysms.
• Findings offer insights for developing postoperative follow-up strategies for flow diverter devices.