A novel method for cerebrospinal fluid diversion: A cadaveric and animal study

BACKGROUND: Cerebrospinal fluid (CSF) diversionary methods are fraught with complications (eg, infection, obstruction, and CSF malabsorption at the distal site). INTRODUCTION: The authors investigated the sternum, specifically the manubrium, as a potential CSF receptacle for patients with hydrocephalus. METHODS: Five fresh adult human cadavers had the manubrium cannulated in a suprasternal location. Tap water was infused via a metal trocar for approximately 60 minutes. Additionally, morphometric examination of the manubrium from 40 adult human skeletons was performed. Next, 4 anesthetized rhesus monkeys underwent cannulation of the manubrium: 2 were infused with 50 mL of saline over approximately 1 hour, and 2 were infused by gravity drip of saline over 24 hours. Finally, 2 adult pigs underwent long-term ventriculosternal tube placement with analysis for function and potential development of osteomyelitis. RESULTS: Thirty liters of water were injected into all cadaveric specimens without overflow or noticeable edema. No fluid accumulation was identified. The manubrium had a mean length, width, and thickness of 5.1 cm, 5.0 cm, and 1 cm, respectively. The animals that underwent infusion of 50 mL of saline and the animals that underwent gravity drip tolerated the procedure without vital sign changes or evidence of saline leakage into the pleural cavity. The 2 pigs did not show any vital sign changes, and, 2 weeks post procedure, they had no findings of osteomyelitis. CONCLUSION: Based on our studies, the manubrium of the sternum appears to be an ideal location for the placement of the distal end of a CSF diversionary shunt when other anatomic receptacles are not an option. In vivo human studies are now required to verify our findings.