Recipient targeting for revascularization using pulsed Doppler ultrasonography for the treatment of an intracranial giant aneurysm

Aneurysmal occlusion after blood flow revascularization is a promising management strategy for the treatment of intracranial giant aneurysms. However, it is necessary to design robust revascularization for preventing postoperative flow-related infarctions caused by abrupt occlusion of the parent vessels. Since direct anastomosis of donor vessels to recipient vessels near giant aneurysms is often difficult, it is preferable to select cortical recipient branches away from the aneurysm, thus providing a sufficient working space for the surgeon. In this paper, the authors' goal was to identify distal cortical recipient arteries on the brain surface, based on pulsed Doppler ultrasonography analysis of blood flow alteration after temporary closure of the efferent vessels. This method is used to visualize the area around the sacrificed vessels, omits intraoperative arteriography or the risk of a surgical trace of the vessels by dissecting the distal sulci, and could be advantageous for necessary and sufficient revascularization.

A Doppler ultrasonographic study of cyclic changes of ovarian perfusion in the Beagle bitch

Changes in intraovarian arterial blood flow were monitored by means of colour-coded and pulsed Doppler ultrasonography in Beagle bitches during the normal oestrous cycle (n = 11) and pregnancy (n = 3), and at PGF(2alpha)-induced luteolysis (n = 4). The ultrasonographic findings were related to the reproductive stage of the bitch, as determined by vaginoscopical and cytological criteria, and by the concentrations of oestradiol, LH and progesterone in peripheral blood plasma. Colour-coded Doppler ultrasonography was used to visualize and estimate intraovarian vascularization, and pulsed Doppler ultrasonography was used to measure the arterial blood flow. The systolic and diastolic peak velocities, the end-diastolic velocity, and the pulsatility index and resistance index were calculated for quantitative analysis of the Doppler waveforms. Intraovarian perfusion increased gradually during pro-oestrus. A marked enhancement of intraovarian colouring and blood flow velocities, and a decline in the indices for pulsatility and resistance were observed in the preovulatory period. Maximum perfusion was observed at ovulation and during the early luteal phase. Significant differences (P < 0.05) were detected for the values of all calculated Doppler parameters 2 days before and 2 days after ovulation. Intraovarian blood flow decreased gradually in accordance with luteal regression. Treatment with PGF(2alpha) caused a distinct decline in luteal activity and a concomitant reduction in intraovarian perfusion. The values of blood flow parameters found during the luteal phase of pregnant bitches were comparable to those of the normocyclic bitches. Doppler ultrasonography of the intraovarian arteries in bitches provides complementary information about cyclic changes of ovarian function.