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Biomedical subjects

Mehmet Sait Albayram

Publications and source records attributed to Mehmet Sait Albayram.

4 recordsLinked to original sources

Follow-up of extracranial vertebral artery stents with Doppler sonography.

OBJECTIVE: The objective of our study was to determine the Doppler sonography findings suggestive of restenosis in the follow-up of patients treated by stent placement in the extracranial vertebral artery. CONCLUSION: Follow-up of vertebral artery stents with Doppler sonography may be performed by direct insonation of the stent or by indirect measurements from the V2 segment (the part of the vertebral artery that courses within the intervertebral foramina). The V2 segment Doppler sonography measurements may guide future examinations and provide essential information regarding the proximally deployed stent.

Aged↗

The effect of an acute decrease in serum estrogen concentration on vessel walls: determination with color and pulsed Doppler ultrasound.

The aim of this study was to determine the effects of an acute decrease in serum estrogen concentration on endothelial function in women with surgically induced menopause through the use of color Doppler ultrasonography. There were 40 women scheduled to undergo total abdominal hysterectomy and bilateral salpingo-oopherectomy who participated in the study; 15 women not undergoing surgery also participated as a control group. Color Doppler ultrasonographic examinations of each surgical patient were obtained 3 days prior to and 7 days after surgery. Baseline measurements of the brachial arteries, including peak systolic velocity, end-diastolic velocity, true mean velocity, arterial diameter, and volume flow, were obtained for each patient. After baseline measurements were established, hyperemia was induced by inflating a blood pressure cuff on each patient's upper arm to suprasystolic pressures for 5 min. To evaluate endothelium-dependent vasodilation, the ultrasonographic appearance of the brachial artery was evaluated after the cuff was deflated and removed from the arm. Measurements of peak systolic velocity, end-diastolic velocity, true mean velocity, arterial diameter, and volume flow were obtained, and were repeated at 1, 3, 5, 10, and 20 min subsequent to removal of the blood pressure cuff. The differences between baseline and maximum values of each Doppler parameter after the cuff deflation were calculated. No significant differences were identified in terms of laboratory findings or systolic and diastolic pressures in pre- and postoperative status of surgical patients, or between surgical patients and the control group. A significant difference in serum estradiol levels during pre- and postoperative periods ( P<0.001) was detected. No significant difference in serum estradiol levels was detected among preoperative surgical patients and members of the control group ( P=0.72). All net changes detected within each group during reactive hyperemia were statistically significant. No significant difference in values was detected among pre-, postoperative, and control subjects. Our study reveals that acute decrease in serum estrogen level does not appear to affect endothelial function; thus, we assume that this is mainly due to the result of postoperative surgical stress.

Blood Flow Velocity↗

Effects of oophorectomy and hormone replacement therapy on the pulsatility indices of hepatic and renal arteries.

OBJECTIVE: To investigate the flow velocity waveform changes of the hepatic and renal arteries in women with surgical menopause who received hormone replacement therapy versus those who did not. METHODS: Eighty women who had undergone surgical menopause were divided into 2 groups. The first group (n = 38) consisted of patients who did not receive estrogen treatments after surgery; patients in the second group (n = 42) did receive treatments. The hepatic and renal arteries of patients in both groups were examined by duplex Doppler ultrasonography before the commencement of hormone replacement therapy and after 2 years of treatment, and the pulsatility indices were calculated. RESULTS: No significant differences were detected in the renal and hepatic artery pulsatility indices of patients in the estrogen treatment group (group 2) before and after total abdominal hysterectomy and bilateral salpingo-oophorectomy (P > .05). No significant differences in preoperative and postoperative hepatic arterial pulsatility indices were detected among patients in group 1 (P > .05). Renal artery pulsatility indices measured before and after total abdominal hysterectomy and bilateral salpingooophorectomy did show a statistically significant difference in group 1 (P < .001). In addition, a statistically significant difference was detected before and after surgery in both groups when pulsatility indices were measured at the second-year control dose. CONCLUSIONS: Hepatic arterial pulsatility indices are not affected in postmenopausal women, but renal artery pulsatility indices rise to some extent in women not receiving hormone replacement therapy.

Adult↗