A novel neurointerventional subarachnoid aqueductoplasty technique for the treatment of aqueductal stenosis: a cadaveric feasibility study.

Objective: Aqueductal stenosis is a common cause of obstructive hydrocephalus, resulting in ventricular dilation and neurological deterioration. Standard treatments such as shunting, endoscopic third ventriculostomy, and traditional aqueductoplasty are effective but are associated with risks including parenchymal injury, infection, and long-term failure. As neurosurgery shifts toward minimally invasive techniques, there is a growing interest in approaches that avoid brain parenchyma transgression. This study introduces a novel neurointerventional method for treating aqueductal stenosis via the subarachnoid route through the foramen magnum and the fourth ventricle using standard endovascular tools.

Methods: Five formalin-fixed, silicone-injected, alcohol-preserved cadaveric heads were studied. Contrast was injected into the ventricular system. Catheters were introduced via simulated lumbar puncture or cisterna magna access and then advanced via the foramen of Magendie into the fourth ventricle and then through the aqueduct, utilizing Cone-beam CT, needle guidance software, and biplane fluoroscopy-guided navigation. A self-expanding stent was deployed in the aqueduct, and balloon aqueductoplasty was performed. Anatomical accuracy and technical success were confirmed via endoscopy through a transcallosal approach.

Results: Aqueductal access was successfully achieved in all specimens without brain parenchymal violation. Stent placement and balloon dilation were performed without complications and confirmed endoscopically.

Conclusion: This novel, image-guided, minimally invasive approach enables aqueductal catheterization via the subarachnoid route. It offers a brain-sparing alternative for treating aqueductal stenosis and may extend to future subarachnoid procedures such as third ventriculostomy or cyst fenestration. In vivo studies are warranted.