Preoperative evaluation of pelvic tumors by Doppler and three-dimensional sonography.

OBJECTIVE: To study a spectrum of systems (two-dimensional transvaginal, transvaginal color Doppler, three-dimensional, three-dimensional power Doppler, and contrast-enhanced three-dimensional power Doppler sonography) for preoperative evaluation of pelvic tumors. METHODS: Two hundred ninety-two patients were evaluated by the 5 complementary methods in preoperative sonographic assessments. We examined adnexal and endometrial morphology, thickness, and volume by two- and three-dimensional sonography and analyzed blood flow by transvaginal color, pulsed Doppler, and three-dimensional power Doppler sonography in all examined patients. In 89 patients with complex adnexal lesions of uncertain malignancy, contrast-enhanced three-dimensional power Doppler sonography was performed. RESULTS: Morphologic assessment by three-dimensional sonography yielded additional information in 58% of cases compared with two-dimensional sonography. Furthermore, this modality was superior to two-dimensional sonography in accurate depiction and diagnosis of 2 cases of fallopian tube carcinoma. Combined morphology and vascular indexing reached sensitivity of 97% and specificity of 99%. Endometrial volume in patients with malignant disease was significantly different (28.2 +/- 0.02 cm3) from that in those who had hyperplasia (7.81 +/- 0.03 cm3), polyps (3.5 +/- 0.02 cm3), or normal endometria (0.8 +/- 0.02 cm3). With combined morphologic and three-dimensional power Doppler examination of endometrial lesions, sensitivity and specificity reached 89% and 97%, respectively. CONCLUSIONS: Combined morphologic and vascular imaging improves preoperative assessment of gynecologic tumors.

Perinatal problems in developing countries: lessons learned and future challenges.

Every year, approximately 600,000 women die of pregnancy-related causes--98% of these deaths occur in developing countries. Complications of pregnancy and childbirth are the leading cause of death and disability among women of reproductive age in developing countries. Of all human development indicators, the maternal mortality ratio shows the greatest discrepancy between developed and developing countries. In fact, maternal mortality itself contributes to underdevelopment, because of its severe impact on the lives of young children, the family and society in general. Furthermore, in addition to more than half a million maternal deaths each year 7 million perinatal deaths are recorded and 8 million infants die during the first year of life. Maternal morbidity and mortality as well as perinatal mortality can be reduced through the synergistic effect of combined interventions, without first attaining high levels of economic development. These include: education for all; universal access to basic health services and nutrition before, during and after childbirth; access to family planning services; attendance at birth by professional health workers and access to good quality care in case of complications; and policies that raise women's social and economic status, and their access to property, as well as the labor force.

Assessment of endometrial receptivity by transvaginal color Doppler and three-dimensional power Doppler ultrasonography in patients undergoing in vitro fertilization procedures.

The objective of this study was to investigate the usefulness of transvaginal color Doppler and three-dimensional power Doppler ultrasonography for the assessment of endometrial receptivity. A total of 89 patients undergoing in vitro fertilization procedures were evaluated for endometrial thickness and volume, endometrial morphology, and subendometrial perfusion on the day of embryo transfer. Neither the volume nor the thickness of the endometrium on the day of embryo transfer had a predictive value for conception during in vitro fertilization cycles (P > .05). Patients who became pregnant were characterized by a significantly lower resistance index, obtained from subendometrial vessels by transvaginal color Doppler ultrasonography (resistance index = 0.53 +/- 0.04 versus 0.64 +/- 0.04, pregnant versus not pregnant, respectively; P < .05), and a significantly higher flow index (13.2 +/- 2.2 versus 11.9 +/- 2.4; P < .05), as measured by a three-dimensional power Doppler histogram. No difference was found in the predictive value of scoring systems analyzing endometrial thickness and volume, endometrial morphology, and subendometrial perfusion by color Doppler and three-dimensional power Doppler ultrasonography. The high degree of endometrial perfusion shown by color Doppler ultrasonography and on three-dimensional power Doppler histograms on the day of embryo transfer can indicate a more favorable endometrial milieu for successful in vitro fertilization.

Vascular impedance of uterine, inferior vesicle, and ophthalmic arteries in postmenopausal women receiving hormonal replacement therapy: comparative Doppler study.

AIM: To investigate the effects of combined hormone replacement therapy (HRT) on vascular impedance of the uterine, the inferior vesicle, and the ophthalmic arteries. METHODS: Thirty-five postmenopausal patients were divided in two groups: 21 patients with 1-5 years of menopause and 14 patients with =6 years of menopause. Each group was examined in basal condition and after 1, 3, and 6 months of HRT. Blood flow impedances of the uterine, the inferior vesicle, and the ophthalmic arteries were analyzed by color Doppler. Estradiol plasma concentrations were assayed on the day of Doppler examination. RESULTS: Analysis of the uterine and inferior vesicle arteries flow velocities showed a significant positive correlation between the resistance index (RI) and years of menopause. Higher impedance values were found in patients with longer menopause duration (p<0.05). In patients with =6 years of menopause, impedances of the uterine and the inferior vesicle arteries were 0. 94+/-0.03 and 0.91+/-0.04, respectively, whereas in patients with 1-5 years of menopause impedances were 0.89+/-0.04 and 0.98+/-0.02, respectively. We noticed no significant correlation between baseline RI and duration of menopause at the level of the ophthalmic artery in either group (0.72 vs. 0.73, respectively; p<0.05). After six months of HRT, plasma estradiol concentrations inversely correlated with RI of the uterine (r=0.2556; p=0.021), the inferior vesicle (r=0.2653; p=0.023), and the ophthalmic (r=-0.2211; p=0.017) arteries. CONCLUSION: Doppler studies of the uterine, the inferior vesicle, and the ophthalmic arteries can provide specific and precise pathophysiological information to assess blood flow variations in correlation with combined HRT.

Warfarin and low-dose aspirin for stroke prevention from severe intracranial stenosis.

Management of symptomatic, intracranial, large-arterial atherosclerosis is controversial. We assessed the safety and efficacy of combining warfarin and low-dose aspirin to prevent stroke from intracranial atherosclerotic stenosis failing prior treatment with either aspirin or warfarin. Patients with severe intracranial stenosis were prescribed combination therapy, warfarin (international normalized ratio [INR] 2 to 3) and aspirin 81 mg daily. Ten men and six women treated with combination therapy had one recurrent ischemic event during 382 months of therapy. No patient suffered a myocardial infarction or sudden vascular death. No serious hemorrhagic complication occurred. The combination of warfarin and low-dose aspirin seems safe and effective in preventing recurrent stroke from symptomatic, intracranial, large-arterial occlusive disease after failure with either aspirin or warfarin monotherapy.

Intra-arterial thrombolysis of embolic proximal middle cerebral artery occlusion from presumed atrial myxoma.

The role of thrombolysis in brain ischemia in patients with atrial myxoma is unknown. A patient with acute brain ischemia and previously undiagnosed atrial myxoma recanalized an occluded middle cerebral artery with intra-arterial thrombolysis. Arterial occlusion from presumed myxoma may be amenable to fibrinolysis. Angiography before treatment in patients with atrial myxoma excludes a myxomatous pseudoaneurysm and permits site-specific thrombolytic instillment.

Monoaminergic substrates underlying cocaine-induced enhancement of somatosensory-evoked discharges in rat barrel field cortical neurons.

Previously, we have described a selective potentiating effect of systemically administered cocaine (0.25-1.0 mg/kg i.v.) on long-latency excitatory responses (E2) of rat "barrel field" cortical neurons to mystacial vibrissae stimulation. The rat trigeminal system receives both norepinephrine (NE) and serotonin (5-HT)-containing afferents, but only minimal input from dopaminergic sources. The goal of the present study was to determine which of these monoamine systems was responsible for the previously observed facilitating action of cocaine on E2 responses of barrel field cortical neurons. Two approaches were used: 1) evaluation of cocaine effects on cortical neuron responses to whisker stimulation in NE- or 5-HT-depleted animals and 2) assessment of the effects of selective monoamine uptake blockers on cortical neuron responses to whisker deflection. Extracellular recordings were obtained from spontaneously active neurons in the barrel field cortex of halothane-anesthetized rats. Spontaneous activity and cellular responses to mechanical displacement of a single whisker were monitored before and after systemic (i.v.) administration of either cocaine or one of the following selective uptake blockers, fluoxetine (5-HT), desipramine (NE) and GBR12909 (dopamine). Cocaine-induced increases in the E2 response were observed in N-(2-chloroethyl)-N-ethyl-2-bromobenzylamine (DSP4, noradrenergic neurotoxin)-treated animals, but were reduced or abolished in p-chlorophenylalanine-treated (5-HT depletion) rats. Fluoxetine and desipramine, but not GBR12909, produced cocaine-like potentiation of the E2 response to whisker stimulation. These results point to a 5-HT-dependent mechanism as the substrate underlying cocaine's facilitating effects on long-latency somatosensory cortical neuron responses to receptive field stimulation.

Systemically administered cocaine selectively enhances long-latency responses of rat barrel field cortical neurons to vibrissae stimulation.

Prominent among cocaine's psychostimulant actions are its abilities to heighten awareness of the sensory surround and induce sensory hallucinations. Although many studies have examined the cellular actions of cocaine in "reward" circuits of the brain, few have investigated the impact of cocaine on neuronal function in primary sensory circuits. The goal of this study was to characterize the effects of cocaine on somatosensory cortical neuronal responsiveness to peripheral activation of afferent synaptic pathways. Extracellular recordings were obtained from spontaneously active single units in the barrel field cortex of halothane-anesthetized rats. The spontaneous firing rate and cellular responses to mechanical displacement of a single whisker on the contralateral face were monitored before and after systemic administration of cocaine (0.25, 0.5, 1.0 and 2.0 mg/kg i.v.). Control responses to whisker stimulation consisted of an initial excitatory burst (E1), a postexcitatory suppression of activity (I) and a secondary excitatory discharge (E2). Cocaine effects on spontaneous discharge were minimal at low doses up to and including 1.0 mg/kg, whereas suppression of spontaneous activity was observed at doses above 2.0 mg/kg. After cocaine injection, E1 responses were unchanged or within +/- 30% of control; however, E2 responses were routinely enhanced 50% to 600% above control levels. I responses were increased in magnitude and/or duration. Such facilitation of E2 and I responses was observed at doses as low as 0.25 mg/kg but most consistently at doses of 0.5 to 1.0 mg/kg. Suppression of evoked responses was observed at doses above 2.0 mg/kg. Cocaine's effects on spontaneous and evoked discharge were rapid in onset. Peak effects occurred at 6 min postinjection and recovery to control patterns of discharge were observed by 20 min postinjection. These results indicate that cocaine consistently exerts a facilitating effect on specific late components of cortical neuron responses to sensory stimuli. Although the neural substrates responsible for this effect have not been identified, such findings demonstrate a clear effect of cocaine on sensory signal transmission at dosages that can support behavioral reinforcement.

Iontophoretic study of speed of action of various muscle relaxants.

The speed of action of nondepolarizing muscle relaxants is inversely related to potency. The hypothesis that this effect occurs at the end plate was tested in a frog (Rana pipiens) cutaneous pectoris muscle preparation. Brief acetylcholine pulses (10-100 ms) were applied iontophoretically from a central barrel of a triple-barrelled microelectrode located near an end plate. Long pulses (10-200 s) of muscle relaxant (gallamine, rocuronium, d-tubocurarine, atracurium, vecuronium, pancuronium, and doxacurium) were applied from one of two other barrels. The responses were a voltage change at the end plate, measured with an intracellular electrode. To evaluate potency, intracellular voltage changes following iontophoretic acetylcholine pulses were measured after application of various concentrations of muscle relaxants. The following were the equilibrium dissociation constants, which represent concentration of relaxant for 50% inhibition of response (mean plus or minus standard deviation): gallamine, 4.56 +/- 0.44 microM (n = 5); rocuronium, 0.71 +/- 0.09 microM (n = 6); d-tubocurarine, 0.59 +/- 0.07 microM (n = 4); atracurium, 0.31 +/- 0.03 microM (n = 4); vecuronium, 0.23 +/- 0.02 microM (n = 5); pancuronium, 0.18 +/- 0.03 microM (n = 3); doxacurium, 0.11 +/- 0.03 microM (n = 5). Both onset and offset of effect of muscle relaxant proceeded with an exponential time course.(ABSTRACT TRUNCATED AT 250 WORDS)