Preliminary experimental study on a newly-developed coating material (liquid cellulose) for cerebral aneurysms

We have developed a new coating material for cerebral aneurysms consisting of cellulose. The possible usefulness of this ethyl cellulose-ethyl acetate solution ("Liquid cellulose") as a coating material was evaluated as follows: 1) The liquid cellulose (ethyl cellulose concentration, 10%; degree of polymerization, 100) and Biobond had pHs of 7.35 and 3.16, and viscosities of 1,385 and 626 cp, respectively. The properties of the coat (N = 30, M +/- SD) of the liquid cellulose and Biobond at a cast coat thickness of 254 microns were as follows: coat thickness after drying (microns), 17.8 +/- 2.8 and 109.8 +/- 44.2; coat formation time (sec), 62 and 1,800; strength of the coat (gm), 432.3 +/- 51.4 and 8.0 +/- 5.6; strength index (kg/cm2), 572.8 +/- 84.7 and 2.4 +/- 1.8; and elongation index (%), 14.8 +/- 3.5 and 705 +/- 188.8, respectively. The coat using liquid cellulose was more physiological and far stronger. It was also more readily manipulated during the operation than Biobond. 2) The liquid cellulose showed excellent adhesiveness when applied to the vascular wall. Sequential histological observations for 12 months showed that the liquid cellulose remained stable without histotoxicity or cracks in the coat. These results indicate the potential usefulness of this agent for reinforcing the vascular wall.