Search results for "DOPPLER"
showing 10 items of 637 documents
Ictal functional TCD for the lateralization of the seizure onset zone—a report of two cases
2004
Ictal functional transcranial Doppler sonography (I-fTCD) was used to lateralize the ictal onset zone in the presurgical evaluation of two patients with temporal lobe epilepsy. In one patient, I-fTCD and ictal SPECT were performed simultaneously during EEG-monitoring. In both patients, results were concordant with the ictal SPECT findings, PET and semiology. I-fTCD seems to be an interesting new method to non-invasively lateralize the seizure onset zone with high temporal resolution. I-fTCD and SPECT may give complementary information to lateralize the seizure onset zone.
Imaging photoplethysmography for clinical assessment of cutaneous microcirculation at two different depths
2016
The feasibility of bispectral imaging photoplethysmography (iPPG) system for clinical assessment of cutaneous microcirculation at two different depths is proposed. The iPPG system has been developed and evaluated for in vivo conditions during various tests: (1) topical application of vasodilatory liniment on the skin, (2) skin local heating, (3) arterial occlusion, and (4) regional anesthesia. The device has been validated by the measurements of a laser Doppler imager (LDI) as a reference. The hardware comprises four bispectral light sources (530 and 810 nm) for uniform illumination of skin, video camera, and the control unit for triggering of the system. The PPG signals were calculated and…
Autonomic regulation of nasal vessels during changes in body position
1994
The effects of postural changes on nasal airflow and nasal capillary blood flow were investigated in 15 healthy volunteers. Measurements were performed following nasal application of saline solution (control), the alpha-1 receptor antagonist prazosin, the alpha-2 receptor antagonist yohimbine, and after application of both prazosin and yohimbine. Nasal airflow in the control experiments did not significantly differ in the upright (362 +/- 166 ml/s), dorsally recumbent (350 +/- 167 ml/s) and 70 degrees head down position (311 +/- 167 ml/s). Following application of prazosin, nasal airflow was reduced to 223 +/- 121 ml/s in the upright position. Prazosin treatment significantly reduced nasal …
Transcranial Doppler ultrasonography in the assessment of cerebral circulation arrest: improving sensitivity by trancervical and transorbital carotid…
2009
INTRODUCTION: Transcranial Doppler (TCD) can detect the cerebral circulation arrest (CCA) in brain death. TCD is highly specific, but less sensitive because of false-negatives accounting for up to 10%. The aim of the study was to explore the diagnostic accuracy of TCD and to determine whether it can be augmented by strategies such as the insonation of the extracranial internal carotid artery (ICA) and sequential examinations. METHODS: Data of 184 patients, who met clinical criteria of brain death, observed from 1998 through 2006, were retrospectively reviewed. The study of cerebral arteries was performed through the transtemporal approach, suboccipital insonation of the vertebro-basilar sys…
Doppler and B-mode ultrasound for avascular nephrotomy.
1983
AbstractDoppler sonography for intraoperative localization of the intrarenal arteries combined with B-scan sonography for intraoperative visualization of stones allows complete stone removal via small radial nephrotomies for which clamping of the renal artery is no longer necessary. Since September 1980 we used this technique on 35 patients with staghorn or recurrent calculi. The main advantages of this technique are exact and quick stone localization, minimal loss of renal function owing to preservation of the intrarenal vascular system, and no need for renal ischemia and cooling.
Is avoidance of surgery possible in patients with perimenopausal ovarian tumors using transvaginal ultrasound and duplex color Doppler sonography?
1993
A total of 108 cases of small perimenopausal ovarian tumors (largest diameter, less than 7 cm) were evaluated by transvaginal sonography and duplex color Doppler sonography; 101 had criteria for benignity and 7 for malignancy. All cysts were punctured and aspirated to avoid unnecessary surgery (benign cases) and establish the cytologic diagnosis as well as to avoid the risk of leakage (malignant cases). Recurrence rate of benign punctured cysts was 25% within 1 year of follow up. No difference in recurrent rate was seen between pre- and postmenopausal patients (19 of 56 cases in the premenopausal group, and five of 28 cases in the postmenopausal group). The larger the cyst, the greater the …
Sympathetic Vasomotor Response of the Radial Artery in Patients With Diabetic Foot Syndrome
2003
OBJECTIVE—Neurophysiological assessment of the peripheral autonomic system is characterized by various limitations. An alternative approach to laser Doppler and venous plethymography is the assessment of the sympathetic vasomotor response of the radial artery obtained by continuous wave Doppler sonography. Nomogram data have been established and demonstrate the temporary disappearance of diastolic flow after coughing or deep inspiration. RESEARCH DESIGN AND METHODS—We assessed the sympathetic vasomotor response in 25 patients (mean age 64 years, range 43–76) with diabetic foot syndrome. The Doppler data were correlated with nerve conduction studies of the median and peroneal nerve, the exte…
Involvement of Jugular Valve Insufficiency in Cerebral Venous Air Embolism
2007
Background. Cerebral venous air entrapment is a rare finding on cranial computed tomography (CT) scan. Peripheral air embolism is discussed as a potential cause. However, the mechanism of retrograde passage through internal jugular valves and veins is unclear. Case Report. The case of a patient is reported, who had air entrapment in the left cavernous sinus. Prior to CT scanning, a peripheral intravenous line had been placed. Ultrasound revealed excessive insufficiency of the left internal jugular valve. To further study the mechanism of embolism, an echo contrast agent was injected into the cubital vein. A Valsalva maneuver resulted in retrograde transition of microbubbles across the insuf…
Intravenous recombinant erythropoietin does not lead to an increase in cerebrospinal fluid erythropoietin concentration
2000
No abstract
Uterine effects of clomiphene citrate in women with polycystic ovary syndrome: a prospective controlled study
2006
Background Previous data on the efficacy of clomiphene citrate, the most commonly used drug for treating anovulatory infertility in patients with polycystic ovary syndrome (PCOS), have shown a discrepancy between ovulation and pregnancy rates. In the present subanalysis (of a larger previously published randomized controlled trial), the effect of clomiphene citrate on several ultrasonographic markers of uterine receptivity in PCOS patients who ovulated under treatment was studied. Methods Thirty-three PCOS women who ovulated under 150 mg daily clomiphene citrate and 33 healthy controls were studied. Uterine, subendometrial and endometrial blood flows, endometrial thickness and pattern were …