The potential utility of the pulsed dye laser in the treatment of cerebral vasospam was investigated in vitro and in vivo in animal models. Laser energy of 2.5 - 15.0 mJ at a wavelength of 480 nm and a pulse duration of 1 usec was delivered via a 320µm quartz fiber. The laser was applied intravascularly to isolated dog basilar arteries (n=8) mounted in a double-cannulated perfusion apparatus and constricted by application of hemolysate. Immediate dilatation occurred, resulting in a 14% average increase in arterial caliber. In second model, the basilar artery was exposed transcilivally in the rabbit. Vessels were constricted either with hemolysate (n=3), or animals had previously been subjected to a double subarachnoid haemorrhage (SAH) (n=10). Extravascular application of the laser resulted in a mean increase in vessel diameter of 32% and 52%, respectively. No recurrence of vasospasm was seen in vessels observed for up to 5 hours after treatment. Histological study revealed no gross change in vessel wall.
Teramura A., Macfarlane, R., Owen, C., de la Torre, R., Gregory, K. W., Parrish, J. A. and Zervas, N. Pulsed Dye Laser Treatment of Experimental Cerebral Vasospasm, Proceedings of International Conference of Cerebral Vasospasm,1990.