Power-law dependence on frequency of the Raman-scattering intensity of percolating networks.
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Journal Article↗
Biomedical subjects
T Terao
Publications and source records attributed to T Terao.
Characterization and tissue distribution of opioid-binding cell adhesion molecule (OBCAM) using monoclonal antibodies.
Monoclonal antibodies to opioid-binding cell adhesion molecule (OBCAM) were produced against a synthetic OBCAM peptide. Immunoblotting analysis revealed that the antibodies reacted with 58 and/or 51 kDa proteins in P2 membranes from bovine, rat, mouse, guinea pig and rabbit brains. In bovine brain, the 58 and 51 kDa proteins were present in the striatum and cerebral cortex at high levels, but not in the pituitary. OBCAM was also detected in the cerebellum mainly in the 51 kDa form. In other tissues, the proteins were found in the spleen at very low levels, but not at all in the liver or kidney of the rat. OBCAM was effectively solubilized from bovine P2 membranes by bacterial phosphatidylinositol specific-phospholipase C (PI-PLC), indicating that OBCAM is a glycosylphosphatidylinositol (GPI)-anchored protein. PI-PLC treatment, however, had little effect on the opioid binding activity of the residual P2 membranes. The molecular weight of the proteins (58 and 51 kDa) was reduced to 36 kDa following treatment with N-glycanase but not further reduced after subsequent treatment with neuraminidase and O-glycanase, suggesting that OBCAM has N-glycosylated carbohydrate chains and that its two isoforms are different, at least, in the degree of N-glycosylation. Taken together, these results suggest that OBCAM consists of 58/51 kDa GPI-anchored glycoproteins which are highly N-glycosylated and are expressed mainly in the nervous system.
Amino Acid Sequence↗
Increased concentrations of plasma epinephrine and norepinephrine in patients with eclampsia.
We measured plasma catecholamine concentrations on admission (after eclamptic fit) and after 6 days of delivery in 21 eclamptic patients and on admission in 15 normotensive pregnant women in Bangladesh. Plasma epinephrine and norepinephrine concentrations in eclamptic patients were significantly higher on admission than those of normotensive pregnant women (P < 0.0001). Plasma catecholamine concentrations and mean arterial blood pressure had return to be almost normal as normotensive pregnant women after 6 days of delivery, resulting in no correlation between mean arterial blood pressure and plasma catecholamines. On admission (after eclamptic fit) mean arterial blood pressure was positively correlated with plasma epinephrine (r = 0.626, P < 0.002) and norepinephrine (r = 0.553, P < 0.008) concentrations in patients with eclampsia. The amount of proteinuria was also significantly correlated with plasma epinephrine (r = 0.515, P < 0.02) and norepinephrine (r = 0.606, P < 0.003) concentrations. Number of convulsions was significantly correlated with concentrations of plasma epinephrine (r = 0.514, P < 0.02), norepinephrine (r = 0.521, P < 0.01) and mean arterial blood pressure (r = 0.535, P < 0.01). A positive correlation was found between time passed after convulsion with plasma epinephrine (r = 0.515, P < 0.02) and norepinephrine (r = 0.570, P < 0.006) concentrations. These suggested that the increased plasma levels of epinephrine and norepinephrine in eclamptic patients were well correlated with the severity of the clinical features of eclampsia.
Adult↗
Urinary trypsin inhibitor: a new drug to treat preterm labor: a comparative study with ritodrine.
UNLABELLED: Prevention of preterm delivery is one of the difficult problems facing obstetricians. beta Adrenergic agonists, especially ritodrine, are commonly used in these cases. OBJECTIVES: The aim of this research was to study and compare the effect of urinary trypsin inhibitor (UTI) which has anti-inflammatory anti-cytokine effects with ritodrine in treating preterm labor. STUDY DESIGN: Patients in preterm delivery were randomly selected to be treated either by ritodrine or UTI. In the ritodrine group, uterine contractions were initially suppressed by high doses of ritodrine (up to 300 micrograms/min) and then a maintenance dose was given until 35 weeks of gestation. In the UTI group one vaginal suppository (5000 U) was used daily for 2 weeks. Patients with recurrent preterm uterine contraction during the initial 14 days of treatment, who needed course of other drugs to suppress the contractions, were excluded from the study. Patients responding to the drugs were followed until delivery. Tocolytic index and elastase concentration in the cervical mucus was calculated. Recurrence rate of uterine contraction and time of elongation of pregnancy since the beginning of treatment was calculated. RESULTS: UTI was more effective than ritodrine in inhibition of recurrent uterine contraction and elongation of pregnancy. No side effects could be observed after treatment with UTI for the mother or the fetus. CONCLUSION: UTI may be a new therapeutic method for the inhibition of preterm delivery through suppression of cytokines and inflammatory mediators.
Adrenergic beta-Agonists↗
Correlated plasma elastase and sera cytotoxicity in eclampsia. A possible role of endothelin-1 induced neutrophil activation in preeclampsia-eclampsia.
The activation of neutrophils was studied in preeclampsia (n = 10) and eclampsia (n = 20) compared to normotensive controls (n = 10) and nonpregnant essential hypertensives (n = 10). Plasma elastase levels were raised in preeclampsia (0.53 +/- 0.32 microgram/mL, P < .002) and eclampsia (1.26 +/- 0.8 microgram/mL, P < .001) respectively compared to normal pregnancies (0.032 +/- 0.009 microgram/mL). The plasma elastases were more elevated in eclamptic cases compared to essential hypertensive (0.53 +/- 0.27 microgram/mL; P = .01) patients. We analyzed the correlation among elastase values, systolic (SBP), mean blood pressures (MBP), endothelin-1 (ET-1) levels and sera cytotoxicity (as measured by fura-2 release from human umbilical venous endothelial cell culture) in eclamptic cases. SBP and MBP were significantly correlated with plasma elastase levels in preeclampsia (r = 0.67, 0.63, respectively; P < .03) and eclampsia (r = 0.49, 0.49, respectively; P < .02). ET-1 levels were correlated with SBP (P = .003) and MBP (P = .001) and corresponding elastase levels (r = 0.606, P < .003) in eclamptic patients. Doses of 10, 25, and 50 pmol/mL of ET-1 increased elastase release in human neutrophil cultures dose and time dependently. Cytotoxicity of eclamptic sera correlated (P < .001) to the corresponding plasma elastase values. Therefore, this study suggests that neutrophil activation and ET-1 induced neutrophil activation occurs in this disease.
Adult↗
Stretching of fetal membranes increases the concentration of interleukin-8 and collagenase activity.
OBJECTIVE: The aim of this study was to determine whether stretching of fetal membranes can increase interleukin-8 concentration and collagenase activity. STUDY DESIGN: Strips of whole fetal membranes, amnion, or muscles of the lower uterine segment were stretched for 2 or 4 hours. Interleukin-8 and collagenase activity were measured in homogenized control and stretched samples. Immunohistochemical staining for interleukin-8 was carried out. RESULTS: The interleukin-8 concentration increased significantly after the whole fetal membranes were stretched for 2 and 4 hours (p <0.0007 and 0.001, respectively). Also, stretching of amnion and muscles of the lower uterine segment for 2 and 4 hours increased the concentration of interleukin-8 significantly (p <0.0007 after 2 and 4 hours, respectively). Collagenase activity was significantly increased after stretching of amnion, amniochorion, and muscles of the lower uterine segment for 4 hours (p <0.0007, 0.006, and 0.0007, respectively). After stretching, samples were darkly stained for interleukin-8 compared with control nonstretched samples. CONCLUSION: Stretching of amnion, amniochorion, and muscles of the lower uterine segment increased interleukin-8 production and collagenase activity.
Amnion↗
Plasma P selectin (GMP-140) and glycocalicin are elevated in preeclampsia and eclampsia: their significances.
OBJECTIVE: We measured the concentrations of plasma P selectin (or GMP-140) and glycocalicin in preeclamptic and eclamptic women. Correlations between these two parameters and blood pressures, platelet counts, or plasma thrombin-antithrombin complex values were evaluated. STUDY DESIGN: By use of enzyme-linked immunosorbent assays we measured the plasma GMP-140 and glycocalicin levels in normal pregnancies (n = 10) and preeclamptic (n = 10) and eclamptic (n = 20) pregnancies. The glycocalicin index was calculated as follows: (glycocalicin x [250 x 10(6)/ml])/(Individual platelet counts). Correlations between plasma GMP-140, glycocalicin, glycocalicin index values, blood pressures, platelet counts, and plasma thrombin-antithrombin complex values were analyzed. RESULTS: Plasma GMP-140 levels were found to be significantly elevated in preeclamptic (p < 0.0005) and eclamptic cases (p < 0.0001) compared with normotensive controls. Plasma glycocalicin (p = 0.01, 0.007) and glycocalicin index (p = 0.005, 0.002) values were also markedly elevated in preeclamptic and eclamptic patients compared with normal pregnant patients. Significant correlations between platelet counts or plasma thrombin-antithrombin complex levels and their corresponding plasma GMP-140 and glycocalicin and glycocalicin index values have been found in preeclamptic and eclamptic cases. However, blood pressures had correlations with GMP-140, glycocalicin, and glycocalicin index values in eclamptic cases. CONCLUSIONS: We demonstrated an elevation of plasma GMP-140 and platelet glycocalicin in preeclampsia and eclampsia. This study also reflects the usefulness of glycocalicin as a marker of platelet activation or turnover and endothelial dysfunction in these diseases.
Adult↗
Biochemical changes in the cervical tissue of rabbit induced by interleukin-8, interleukin-1beta, dehydroepiandrosterone sulphate and prostaglandin E2: a comparative study.
The aim of this research was to study and compare the mechanism of action of interleukin (IL)-8, IL-1beta dehydroepiandrosterone sulphate (DHEA-S) and prostaglandin (PG)E2 on the cervix. Five equal groups of pregnant rabbits (n = 45) were tested by either placebo or tested drugs in the form of vaginal suppositories once daily for 3 days. The suppositories contained human recombinant IL-8 (100 ng), IL-1beta (200 ng), DHEA-S (10 mg) or PGE2 (1 mg). All rabbits were tested by one dose, two doses or three doses. Consistency, dilatation and water contents were estimated 24 h after the last dose of treatment. Leukocyte infiltration of the cervices was studied after staining the cervical tissue sections with antirabbit RT2 monoclonal antibodies. Relative collagen concentration was assessed after staining with Picrosirius Red. Collagenase, gelatinase and elastase activities were measured in 100 mg of homogenized cervical connective tissue. Water contents were significantly increased in all tested cervices. Neutrophil numbers were increased in IL-8 and IL-1beta groups after the second dose of treatment (P < 0.0005 and 0.001 respectively). In the PGE2 group, neutrophils were increased after the third dose of treatment, whereas in DHEA-S group no significant changes were observed. Collagen content was significantly decreased in IL-8, IL-1beta and PGE2 groups after the first dose of treatment (P < 0.004, and 0.005 and 0.03 respectively). In the DHEA-S group, the decrease in collagen content occurred after the third dose (P < 0.05). Collagenase activity was markedly increased in IL-8, IL-1, and DHEA-S groups after the second dose of treatment (P < 0.001, 0.003 and 0.007 respectively). No significant increase in collagenase activity was found in PGE2 group. Gelatinase activity was significantly increased in IL-8, IL-1beta, PGE2 and DHEA-S groups after the second dose of treatment (P < 0.008, 0.01, 0.003 and 0.05 respectively). Also, elastase activity was increased after the second dose of treatment in all groups (P < 0.001, 0.001, 0.001 and 0.006 respectively). Our data suggest that ripening of the cervix in rabbit can be initiated by different mechanisms. Cytokines play a vital role in cervical ripening, especially IL-8 and IL-1. IL-8 is one of the factors which could ripen the cervix in a manner similar to the physiological process at term.
Animals↗
Novel drought-inducible genes in the highly drought-tolerant cowpea: cloning of cDNAs and analysis of the expression of the corresponding genes.
Ten cDNAs of genes that were induced by dehydration stress were cloned by differential screening from the highly drought-tolerant legume, cowpea (Vigna unguiculata), a major crop in West Africa. The clones were collectively named CPRD (cowpea clones responsive to dehydration). Northern blot analysis revealed that nine of the CPRD genes were induced by dehydration stress, but the timing of induction of mRNA synthesis varied among the CPRD genes. We analyzed the effects of other environmental stresses on the expression of the CPRD8, CPRD14 and CPRD22 genes, and we found that these genes were strongly induced by high-salinity stress but not by cold or heat stress. Drought-stressed cowpea plants accumulated abscisic acid (ABA) to a level that was 160 times higher than that in unstressed plants. The CPRD8 and CPRD22 genes were induced to a significant extent by the application of exogenous ABA but the CPRD14 gene was not. These results indicate the existence of at least two signal-transduction pathways between the detection of water stress and the expression of CPRD genes in cowpea. Sequence analysis of CPRD8 and CPRD22 cDNAs revealed that they encoded putative proteins that were related to old yellow enzyme and group 2 LEA proteins, respectively. The protein encoded by CPRD14 exhibited sequence homology to dihydroflavonol-4-reductase (DFR) and vestitone reductase (VR). Old yellow enzyme, DFR and VR have not been identified as drought-inducible proteins in other plants, whereas LEA genes have been well characterized as drought-inducible genes. The various gene products might function to protect cells from environmental stress.
Abscisic Acid↗
Vitamin K prophylaxis to prevent neonatal vitamin K deficient intracranial haemorrhage in Shizuoka prefecture.
OBJECTIVE: To compare three methods of vitamin K prophylaxis for neonatal vitamin K deficient intracranial haemorrhage. DESIGN: We designed three strategies for vitamin K prophylaxis: 1. therapeutic administration of vitamin K in a mass screening system using the hepaplastin test; 2. routine oral administration of vitamin K to newborn infants; and 3. administration of vitamin K to lactating mothers during the late neonatal period in addition to the routine method. We evaluated the efficacy of these methods by determining hepaplastin test values at the first month of age. POPULATION: 66,076 full term healthy newborn infants without any complications. RESULTS: Of 55,513 infants in the mass screening system, 3068 infants received vitamin K therapeutically. At the first month of age, in the group where vitamin K was administered therapeutically, 56 infants (1.83%) exhibited low hepaplastin test values (< 40%) despite vitamin K administration. But extremely low values (< 20%), indicating a very high risk of neonatal intracranial haemorrhage, were observed in 34 (0.06%) of 52,445 infants who did not receive vitamin K. In the routine administration system, oral administration of vitamin K twice within the first week of life showed a lower incidence (0.19%) of low level cases than a single administration (1.56%). An additional administration of vitamin K to lactating mothers throughout the late neonatal period showed an effective result.
Administration, Oral↗
Irreversible sinus node dysfunction induced by resumption of lithium therapy.
We present the case of a 56-year-old woman with syncope and sinus node dysfunction after long-term lithium therapy. Following lithium discontinuation, sinus node function recovered completely. After resuming low doses of lithium, however, severe sinus node dysfunction recurred. Thereafter, sinus node function did not recover after lithium was discontinued, and a permanent pacemaker was implanted. These findings suggest that irreversible sinus node dysfunction should be recognized as a potentially fatal, albeit rare, risk of lithium therapy, and that previous recovery from sinus node dysfunction after long-term lithium treatment cannot always guarantee the reversible nature of this abnormality after resumption of lithium therapy.
Adult↗
Active secretion of drugs from the small intestinal epithelium in rats by P-glycoprotein functioning as an absorption barrier.
Because the significance of P-glycoprotein in the in-vivo secretion of beta-blockers in intestinal epithelial cells is unclear, the secretory mechanism for beta-blockers and other drugs has been evaluated. Uptake of the beta-blockers acebutolol, celiprolol, nadolol and timolol, and the antiarrhythmic agent, quinidine by the multidrug-resistant leukaemic cell line variant K562/ADM was significantly lower than that by drug-sensitive K562 cells, suggesting that these beta-blockers are transported by P-glycoprotein out of cells. The reduced uptake of acebutolol by the drug-resistant K562/ADM cells was reversed by treating the cells with anti-P-glycoprotein monoclonal antibody, MRK16, whereas no such alteration in uptake was observed for drug-sensitive K562 cells. Acebutolol uptake by K562/ADM cells was, moreover, markedly enhanced, in a concentration-dependent manner, in the presence of the specific P-glycoprotein inhibitors, MS-209 and cyclosporin. Caco-2 cells were used for evaluation of the role of P-glycoprotein in intestinal permeability to drugs in-vitro. Basolateral-to-apical transport of acebutolol was twice that in the reverse direction. A similar polarized flux was also observed in the transport of vinblastine, but not in that of acetamide or mannitol. When in-vivo intestinal absorption was evaluated by the rat jejunal loop method, with simultaneous intravenous administration of a P-glycoprotein inhibitor, cyclosporin, intestinal absorption of both acebutolol and vinblastine increased 2.6- and 2.2-fold, respectively, but no such enhancement was observed in the absorption of acetamide. The effect of cyclosporin on the intestinal absorption of several drugs was further examined, and the extent of the contribution of P-glycoprotein as an absorption barrier to those drugs was evaluated. ATP depletion by occlusion of the superior mesenteric artery resulted in a clear increase in epithelial permeability to vinblastine, but not to 3-O-methylglucose or acetamide, indicating that vinblastine is secreted by ATP-dependent P-glycoprotein into the lumen. These findings demonstrate that P-glycoprotein plays a role as an absorption barrier by transporting several drugs from intestinal cells into the lumen.
ATP Binding Cassette Transporter, Subfamily B, Mem↗
Congenital afibrinogenemia with successful delivery.
We experienced a case of congenital afibrinogenemia and successfully performed cesarean section with administration of fibrinogen. The patient was administered fibrinogen every week to sustain a fibrinogen level above 60 mg/ dl according to our previously reported first case. Pregnancy course was uneventful, and fetal growth was normal, but unfortunately placental abruption occurred after the spontaneous onset of labor at 37 weeks gestation. The fibrinogen level before labor was 96 mg/dl, but decreased to 33 mg/dl when placental abruption was diagnosed. During and after the operation, it was increased to 147 and 199 mg/dl, respectively, through infusion of 10 g of fibrinogen, and massive bleeding was stopped. Two grams of fibrinogen were infused daily after cesarean section, and postpartum hemorrhage was normal. It is obvious that fibrinogen is an extremely important factor in maintaining pregnancy, and we conclude that fibrinogen level must be at least 60 mg/dl during pregnancy, 120 mg/dl during surgery and 150 mg/dl during labor, if possible as high as 200 mg/dl under the continuous infusion of fibrinogen to prevent placental abruption.
Adult↗
Fibrinolysis during normal pregnancy and severe preeclampsia relationships between plasma levels of plasminogen activators and inhibitors.
The antigen levels of plasminogen activator inhibitor type 1 (PAI-1), plasminogen activator inhibitor type 2 (PAI-2), tissue-type plasminogen activator (t-PA), and urokinase-type plasminogen activator (u-PA) were measured during pregnancy and severe preeclampsia. The PAI-1 and PAI-2 antigen levels increased linearly during pregnancy and promptly returned to the level of non-pregnant women after delivery. The t-PA and u-PA antigen levels increased slowly and linearly during pregnancy. In severe preeclampsia, the PAI-2 antigen level was lower than that observed during the 3rd trimester of normal pregnancy, and the t-PA antigen level was higher than that during the 3rd trimester of normal pregnancy. Immunohistochemical examination of placental tissue showed that the PAI-2 and u-PA antigens were localized in syncytiotrophoblasts. In severe preeclampsia, the PAI-2 and u-PA antigens in placental tissue did not stain as clearly as during the 3rd trimester of normal pregnancy. The PAI-2 and u-PA antigen levels showed a positive correlation with birth weight. Therefore, PAI-2 may be an important marker of placental function and abnormality in pregnancies.
Antibodies, Monoclonal↗
Dehydroepiandrosterone sulfate potentiates the effect of interleukin-8 on the cervix.
Dehydroepiandrosterone sulfate (DHA-S) is one of the successful drugs used to induce cervical ripening. There is growing evidence that interleukin-8 (IL-8) plays an essential role during cervical ripening. IL-8 was found to be hormonally controlled in the cervix. The aim of this research was to study the effect of DHA-S on the function of IL-8 on the cervix. Sixteen pregnant white New Zealand rabbits where tested either by placebo (adeps solidus, n = 4), DHA-S (10 mg, n = 4), IL-8 (100 ng, n = 4) or combination of DHA-S and IL-8 (n = 4). Collagen contents in the cervices were assessed histologically after staining with picrosirius red. The number of neutrophils in 5 random fields of the cervical tissue was counted in all groups. Collagenase, elastase and gelatinase were measured in those groups. The collagen content of the cervices was significantly decreased after treatment with DHA-S, IL-8 or a combination of both drugs compared to the control group (p < 0.004, 0.001 and 0.001, respectively). A maximal decrease in collagen content was found in the DHA-S + IL-8-treated group (71.5%). Neutrophil infiltration was significantly increased in the IL-8 and DHA-S + IL-8-treated groups (p < 0.0001). Neutrophil numbers in the DHA-S + IL-8-treated group were significantly higher than in the IL-8 group (p < 0.006). Collagenase activity was increased in the DHA-S, IL-8 and DHA-S + IL-8 groups compared to the control group (p < 0.02, 0.008 and 0.001, respectively). Elastase activity was also significantly increased in the same groups (p < 0.002, 0.005 and 0.001, respectively). A similar increment was found in gelatinase activity (p < 0.004, 0.0001 and 0.0001, respectively). DHA-S has a synergistic effect with IL-8 during cervical ripening.
Animals↗
Effects of urinary trypsin inhibitor on myometrial contraction in term and preterm deliveries.
The aim of this research was to study the concentration of urinary trypsin inhibitor in amniotic fluid (AF) and its effect on myometrial contraction in term and preterm deliveries. Urinary trypsin inhibitor was measured in AF of term and preterm labor. Immunohistochemical staining of amnion and myometrium was carried out. Isometric uterine contraction was studied to elucidate the effect of AF and urinary trypsin inhibitor on the contractile activity of term and preterm myometrium. The effect of urinary trypsin inhibitor on the production of prostaglandin E2 (PGE2) from myometrial cultures stimulated by IL-8, IL-1 and LPS was verified. Urinary trypsin inhibitor was significantly increased in AF of cases of preterm delivery (p < 0.0001). Amnion and myometrium of preterm deliveries were faintly stained for urinary trypsin inhibitor compared to term delivery. Amniotic fluid and urinary trypsin inhibitor could successfully inhibit-myometrial contraction. Also, urinary trypsin inhibitor could significantly inhibit the production of PGE2 in the myometrial cell cultures stimulated by IL-1 and LPS (p < 0.001 and 0.0005). IL-8 has no significant effect on PGE2 production from myometrial cell culture. Urinary trypsin inhibitor suppresses myometrial contraction in term and preterm deliveries. It may play a role in maintaining normal pregnancy and preventing preterm delivery.
Amnion↗
Immunohistological study in cases of HELLP syndrome (hemolysis, elevated liver enzymes and low platelets) and acute fatty liver of pregnancy.
We immunohistologically studied the hepatic tissue sections in cases with the syndrome of hemolysis, elevated liver enzymes, and low platelets (HELLP syndrome; n = 2) and acute fatty liver of pregnancy (AFLP; n = 2) compared to necropsy controls. Unlike in the AFLP cases, a marked infiltration of neutrophils in liver tissues was found in both cases of the HELLP syndrome. Immunostaining with the antihuman (polyclonal) TNF-alpha, IL-1 beta, IL-8 and antihuman neutrophil elastase (monoclonal antibody) was performed in paraffin-embedded hepatic tissue sections. Liver tissues in HELLP syndrome patients were stained strongly with TNF-alpha and neutrophil elastase antibody. The strongest staining pattern was observed in the eclamptic case, whereas in the AFLP cases, as in the necropsy controls, a very weak staining for anti-TNF-alpha and elastase antibody was found. The liver sections of the HELLP syndrome cases were moderately stained with polyclonal IL-1 beta and IL-8 antibodies whereas AFLP and controls had a very faint staining. Significant correlations were found between the numbers of necrotic hepatocytes and elastase dots in the same microscopic fields (randomly selected) of liver sections from two cases of HELLP syndrome (r2 = 0.63; p < 0.0001), which might suggest a neutrophil-mediated tissue damage in such a disease. This study suggests that a cytokine- and neutrophil-mediated liver injury occurs in the HELLP syndrome but not in AFLP.
Adult↗
Transvenous hemodynamic assessment of arteriovenous malformations and fistulas. Preliminary clinical experience in Doppler guidewire monitoring of embolotherapy.
BACKGROUND AND PURPOSE: Transvenous monitoring of blood flow through intracranial vascular malformations was performed with an intravascular Doppler guidewire to assess hemodynamic changes during endovascular embolotherapy. METHODS: Flow velocity was assessed in the intracranial venous sinuses of two patients with arteriovenous malformations and seven patients with dural arteriovenous fistulas. In all cases, the Doppler guidewire was positioned in the dural sinuses coaxially through a 2.1F microcatheter. The Doppler guidewire was then advanced to the site of arteriovenous shunting for sampling of venous average peak velocity (APV) and pulsatility index. In two cases, simultaneous feeding artery flow velocity was monitored by transcranial color-coded duplex sonography. RESULTS: Before embolotherapy, the flow pattern in the venous sinuses was pulsatile, with a mean (+/-SD) APV of 39.0 +/- 22.5 cm/s. Total or near-total embolization was achieved in six of the nine cases. After embolization, the flow pattern became less pulsatile and the APV was reduced to a mean of 21.2 +/- 14.6 cm/s (P = .0123, one-tailed paired t test). The pulsatility index was used to calculate the maximum minus the minimum peak velocity (MxPV-MnPV). This was reduced from an average of 27.0 +/- 8.7 cm/s to 13.5 +/- 8.3 cm/s after treatment (P = .0456). A parallel reduction in APV of the feeding arteries was observed with embolization. CONCLUSIONS: Preliminary clinical experience indicates that transvenous assessment of two parameters, APV and MxPV-MnPV, is useful in the hemodynamic evaluation of intracranial arteriovenous shunts. This valuable hemodynamic information may be used for objective and quantitative monitoring during embolotherapy of intracranial vascular malformations.
Adolescent↗