Ventricular catheters are used to treat hydrocephalus by diverting the excess of the cerebrospinal fluid (CSF) to the reabsorption site so as to regulate the intracranial pressure. The failure rate of these shunts is extremely high due to the ingrown tissue that blocks the CSF flow. We have studied a method to image the occlusion inside the shunt through the skull. In this approach the pulsed laser light coupled to the optical fiber illuminate the occluding tissue inside the catheter and an external ultrasound transducer is applied to detect the generated photoacoustic signal. The feasibility of this method is investigated using a phantom made of ovis aries brain tissue and adult human skull. We were able to image the target inside the shunt located 20mm deep inside the brain through about 4mm thick skull bone. This study could lead to the development of a simple, safe and non-invasive device for percutaneous restoration of patency to occluded shunts. This will eliminate the need of the surgical replacement of the occluded catheters which expose the patients to risks including hemorrhage and brain injury.

Date Published: 3 March 2014
PDF: 8 pages
Proc. SPIE 8943, Photons Plus Ultrasound: Imaging and Sensing 2014, 89434O (3 March 2014); doi: 10.1117/12.2040805

Published in SPIE Proceedings Vol. 8943:
Photons Plus Ultrasound: Imaging and Sensing 2014
Alexander A. Oraevsky; Lihong V. Wang, Editor(s)