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Biomedical subjects

Y Sunami

Publications and source records attributed to Y Sunami.

At least 19 recordsLinked to original sources
PubMed2007

A simple protocol for preventing falls and fractures in elderly individuals with musculoskeletal disease.

UNLABELLED: Our protocol resulted in a significant prevention of falls and fractures in addition to marked improvements in the balance function. Intervention comprised a new balance exercise and quadriceps femoris exercise. Subjects were outpatients aged >or=65 years old with musculoskeletal disorders who had a result of or=65 years old and had a result of <or=15 s for the timed one-leg balance test with eyes open. Intervention consisted of a new balance exercise and quadriceps femoris exercise regimen. The main outcome was fall rate, while secondary outcomes were the results of the timed one-leg balance test with eyes open and fracture rate. RESULTS: Fall rate was decreased by 44% (p < 0.001) and fracture rate by 47% (p < 0.05) by 8 months after the start of the intervention. The results of the timed one-leg balance testing with eyes open improved two- to threefold after intervention (p < 0.01). CONCLUSIONS: Our protocol has been safely implemented at a large number of clinics in Japan, and the reductions in frequency of falls and fractures suggest that it provides effective preventive care.

Accidental Falls↗
PubMed2001

Is a role of phospholipase A(2) in cholesterol gallstone formation phospholipid species-dependent?

Phospholipase A(2) plays a role in cholesterol gallstone formation by hydrolyzing bile phospholipids into lysolecithin and free fatty acids. This study investigated its effects on cholesterol crystallization in model bile systems. Supersaturated model bile solutions with different cholesterol saturation indexes (1.2, 1.4, and 1.6) were prepared using cholesterol, taurocholate, and egg yolk phosphatidylcholine, soybean phosphatidylcholine, palmitoyl-oleoyl phosphatidylcholine, or palmitoyl-linoleoyl phosphatidylcholine. Then the effect of digestion of phosphatidylcholine by phospholipase A(2) on bile metastability was assessed by spectrophotometry and video-enhanced differential contrast microscopy. Addition of phospholipase A(2) caused the release of free fatty acids in a time-dependent manner. Cholesterol crystallization was enhanced by an increased crystal growth rate in model bile containing hydrophilic species such as soybean or palmitoyl-linoleoyl phosphatidylcholine, consisting predominantly of polyunsaturated fatty acids. Because phospholipase A(2) enhanced cholesterol crystallization in bile containing hydrophilic phosphatidylcholine species, but not hydrophobic phosphatidylcholine species, release of polyunsaturated fatty acids by hydrolysis may be responsible for such enhancement. Therefore, the role of phospholipase A(2) in cholesterol gallstone formation depends on the phospholipid species present in bile, so that phospholipid species selection during hepatic excretion is, in part, crucial to the cholesterol stone formation.

Bile↗
PubMed2001

Dose-dependent conjugation of sulfobromophthalein and hepatic transit time in bile fistula rats: role of the microtubule-dependent vesicle pathway.

Sulfobromophthalein (BSP) is selectively taken up by the liver and secreted into the bile as unconjugated and conjugated forms. Our previous study demonstrated that unconjugated BSP, but not conjugated BSP, caused the dissociation of biliary lipid secretion from that of bile acids, suggesting that the hepatic BSP conjugation rate partly regulated biliary lipid secretion. To evaluate the mechanisms through which biliary lipid secretion is regulated by exogenous organic anions, we intravenously administered BSP to male Sprague-Dawley rats at various doses either continuously or as a bolus. Then the relationship of the dose of BSP to its conjugation rate, hepatic transit time, and biliary lipid secretion was determined. BSP decreased biliary secretion of cholesterol and phospholipids in a dose-dependent manner without affecting bile acid secretion. In contrast, the proportion of conjugated BSP in bile was associated with the dose. Although the serum clearance of BSP after bolus infusion was constant regardless of the dose administered (50 or 200 nmol/100 g), BSP secretion was delayed with increasing doses: unconjugated BSP was secreted predominantly in the early phase (0-15 min after bolus injection), and conjugated BSP was the predominant form in the late phase (15-30 min). Pretreatment with colchicine reduced the conjugation rate and hepatic transit time of BSP, suggesting that the microtubule-dependent vesicle pathway plays a role in biliary excretion and conjugation of BSP. We conclude that biliary lipid secretion is influenced by organic anions with an affinity for bile acids such as BSP and that this effect is dependent upon the hepatic metabolic rate, i.e., conjugation rate. The hepatic transit time also plays a key role in this process by influencing metabolism.

Animals↗
PubMed2001

Phospholipid alterations in hepatocyte membranes and transporter protein changes in cholestatic rat model.

Biliary components are transported by hepatic adenosine triphosphate-binding cassette (ABC) transporters that are located in canalicular membranes. Physiological transporter function is related to membrane fluidity, which is modulated by the phospholipid composition of the lipid bilayer. We hypothesized that cholestasis may alter transporter function by modifying phospholipid species to protect the cell from cholestatic damage. Therefore, we examined the expression of ABC transport proteins and their mRNA levels in canalicular membrane vesicles isolated from rat liver 6 hr or three days after bile duct ligation. Membrane lipid composition and membrane fluidity of both sinusoidal and canalicular membrane vesicles were also examined. By 6 hr after bile duct ligation, we found a clear increase of mdr2 and bsep mRNA. These changes were associated with an increase of mdr-Pgp and with a clear decrease of mrp2 protein, and small decrease of bsep protein. In addition, mdrlb mRNA showed a strong increase by three days after bile duct ligation. Canalicular membrane fluidity decreased in a marked time-dependent manner, whereas sinusoidal membranes showed biphasic changes: increased fluidity at 6 hr and a decrease at three days. These changes were closely related to the changes of membrane lipid constitution; the saturated/unsaturated fatty acid ratio increased for phosphatidylcholine in canalicular membrane and the reverse occurred in sinusoidal membrane, and those for sphingomyelin showed the opposite pattern. We conclude that cholestasis causes modulation of ABC transporters as well as that of the lipid constitution in lipid bilayer. These may confer cytoprotective resistance to hepatocytes against cholestatic stress.

ATP-Binding Cassette Transporters↗
PubMed2000

Role of phospholipase A2 in cholesterol gallstone formation is associated with biliary phospholipid species selection at the site of hepatic excretion: indirect evidence.

Phospholipase A2 plays a role in cholesterol gallstone development by hydrolyzing bile phospholipids into lysolecithin and free fatty acids. Lysolecithin and polyunsaturated free fatty acids are known to stimulate the synthesis and/or secretion of gallbladder mucin via a prostanoid pathway, leading to enhancing cholesterol crystal nucleation and growth, and therefore, the action of phospholipase A2 is associated, in part, with bile phospholipid fatty acid. To clarify this hypothesis, we evaluated the effect on bile lipid metastability in vitro of replacing phospholipids with lysolecithin and various free fatty acids. Supersaturated model biles were created with an identical composition (cholesterol saturation index, 1.8; egg yolk lecithin, 34 mM; taurocholate, 120 mM; cholesterol, 25 mM) except for 5%, 10%, or 20% replacement of egg yolk lecithin with a combination of palmitoyl-lysolecithin and a free fatty acid (palmitate, stearate, oleate, linoleate, or arachidonate), followed by time-sequentially monitoring of vesicles and cholesterol crystals using spectrophotometer and video-enhanced differential contrast microscopy. Replacement with hydrophilic fatty acids (linoleate and arachidonate) reduced vesicle formation and promoted cholesterol crystallization, whereas an enhanced cholesterol-holding capacity was evident after replacement with hydrophobic fatty acids (palmitate and stearate). These results indicate that the effect of phospholipase A2 on bile lithogenecity is modulated by the fatty acid species in bile phospholipids, and therefore, that the role of phospholipase A2 in cholesterol gallstone formation is dependent, in part, on biliary phospholipid species selection at the site of hepatic excretion.

Bile↗
PubMed2000

Gallbladder dysfunction enhances physical density but not biochemical metastability of biliary vesicles.

The gallbladder role in cholesterol gallstone pathogenesis occurs through modulation of bile cholesterol metastability. The present study characterized the effects of concentrating bile on cholesterol crystallization through vesicle transformation, crystal habits, and potentiation of effector substances. Supersaturated model biles with total lipid concentrations of 12, 9, 6, and 3 g/dl were prepared with identical molar ratios (taurocholate-egg yolk phosphatidylcholine-cholesterol: 71:18:11). Bile metastability was assessed spectrophotometrically, and morphology of vesicle and crystal was sequentially scanned by video-enhanced differential contrast microscopy. The effects of replacing 30% of egg yolk phosphatidylcholine with soy bean phosphatidylcholine, 30% of taurocholate with taurodeoxycholate or tauroursodeoxycholate, and addition of concanavalin A-binding glycoprotein on each model bile were examined. By lowering total lipid concentration, cholesterol crystallization was retarded with less fusion and aggregation of vesicles. The effects of substances promoting cholesterol crystallization were enhanced with lesser bile. By replacing 30% of taurocholate with tauroursodeoxycholate, cholesterol crystallization was markedly inhibited in all concentrations, forming stable liquid-crystals. Impaired water absorption by the gallbladder may stabilize vesicles and inhibit rapid cholesterol crystallization, but the potential of cholesterol crystallization effector substances must be modified to alter bile cholesterol metastability.

Bile↗
PubMed2000

Factors affecting gallstone recurrence after successful extracorporeal shock wave lithotripsy.

Ninety-six patients treated successively for symptomatic cholelithiasis with extracorporeal shock wave lithotripsy (ESWL) and oral bile acid therapy consisting of ursodeoxycholic acid in daily dosages of 600 mg were prospectively followed for gallstone recurrence for a median of 13 months. Ultrasonography was performed to detect stone recurrence at 3, 6, and 12 months, and then yearly after the termination of therapy. Recurrent stones were found in 17 patients (18%). The cumulative probability of gallstone recurrence was 15.8% at 12 months, 26.1% at 24 months, and 30.7% at 36 months. The probability of stone recurrence over the entire period of observation was not dependent on stone number, whereas the median interval to detection of recurrence was significantly shorter in the patients with multiple stones (2 months) than in those with solitary stones (8 months) (p < 0.05). The rate of impaired gallbladder contractility was higher in patients with recurrence (8/15, 53.3%) when compared with those with no recurrence (15/72, 20.8%) (p < 0.01). Neither age, gender, or stone characteristics predicted stone recurrence. Only one patient with a recurrence reported biliary pain. Of the 15 patients with recurrent stones who opted for further nonsurgical treatment, complete stone disappearance was achieved in 10. Impaired gallbladder function may predict gallstone recurrence after ESWL.

Cholagogues and Choleretics↗
PubMed2000

Enhanced visualization of weak colloidal iron signals with Bodian's protein silver for demonstration of perineuronal nets of proteoglycans in the central nervous system.

The present study aimed for a clear visualization of faintly deposited colloidal iron in tissue sections for light microscopy. Paraffin blocks containing paraformaldehyde-fixed brain tissue from healthy adult mice were cut into sections 10-15 microm thick. After deparaffinization, the sections were stained with fine cationic iron colloid at a pH value of 1.0-1.5, and treated with a mixture of potassium ferrocyanide and hydrochloride for Prussian blue reaction. Some sections were further treated with Bodian's protein silver after the Prussian blue reaction. This sensitized development of Prussian blue reaction with Bodian's protein silver more clearly visualized the faintly deposited cationic colloidal irons than the demonstration by Prussian blue reaction alone, and allowed an enhanced visualization of the perineuronal nets of sulfated proteoglycans in the brain. Thus, such fine perineuronal sulfated proteoglycans as those in the CA3 field of the hippocampus, which are weakly stained with cationic iron colloid and usually overlooked by a demonstration with only a Prussian blue reaction, could be clearly visualized with striking contrast by the sensitized development with Bodian's protein silver after the Prussian blue reaction. Preliminary hyaluronidase digestion erased Bodian's protein silver development of perineuronal sulfated proteoglycans. Though some axonal fibers were also additionally stained with Bodian's protein silver itself, this sensitized development is useful to enhance such weak colloidal iron signals as are hardly detectable by only Prussian blue reaction.

Animals↗
PubMed1999

Effects of low-intensity aerobic training on the high-density lipoprotein cholesterol concentration in healthy elderly subjects.

The concentration of high-density lipoprotein cholesterol (HDL-C) is inversely correlated with the risk of coronary heart disease. The effects of low-intensity aerobic training on serum HDL-C and other lipoprotein concentrations were examined in healthy elderly subjects. The subjects were randomly assigned to two groups matched for sex, age, height, and weight. The training group (n = 20, 10 men and 10 women aged 67 +/- 4 years) participated in a supervised physical exercise regimen using a bicycle ergometer at an intensity of 50% estimated maximal oxygen consumption (VO2max) for 60 minutes two to four times per week for 5 months. In contrast, the control group (n = 20, 10 men and 10 women aged 68 +/- 4 years) did not perform any particular physical training. The training protocol resulted in significant increases in the VO2max (P < .05), HDL-C, HDL2-C, and HDL2-C/HDL3-C ratio (P < .01). The change in HDL2-C (r = .57, P < .01) and HDL2-C/HDL3-C (r = .63, P < .01) was positively associated with an increase in the total exercise duration per week. In addition, the total weekly exercise duration also showed a significant positive relationship with HDL-C (r = .75, P < .01), HDL2-C (r = .81, P < .01), and HDL2-C/HDL3-C (r = .71, P < .01) after the training period. The changes in body weight and the VO2max were not significantly correlated with any lipid parameters. Low-intensity aerobic training may improve the profile of HDL-C and its subfractions in healthy elderly subjects. Also, the total exercise duration may be an important factor for improving HDL-C and HDL2-C in elderly subjects.

Aged↗
PubMed1999

[The effects of low intensity aerobic training on the physiological indexes and the quality of life in middle-aged white collar workers].

The effects of short-term low intensity aerobic training on the physiological indexes and the Quality of Life were examined in 43 middle-aged White Collar Workers. Training was carried out for 205 +/- 117 minutes/week, at least 2-3 times/week for 2 months on a cycle ergometer or walking with intensity level set at the 50% VO2max. Following this training protocol, thirty-six men (exercise group) completed the 2-month training program and 7 men dropped out (the dropout group). In the exercise group, both the VO2max (l/min) and VO2max/wt increased significantly (VO2max (l/min): P < 0.05. VO2max/wt: P < 0.01), whereas the weight, body mass index, %fat, fat (kg) and the waist hip ratio (WHR) decreased significantly (WHR: P < 0.05, others: P < 0.01) after 2 months. In addition, the DBP and serum TC, LDL-c/HDL-c decreased significantly (LDL-c/HDL-c: P < 0.01, others: P < 0.05) whereas the HDL-c increased significantly (P < 0.05). A modified Croog questionnaire was used to assess the subject's Quality of Life. The questionnaire consisted of 59 questions and the overall assessment was based on eight components. Regarding the Quality of Life, physical symptoms, work performance and satisfaction, total Quality of Life all improved significantly (physical symptoms, P < 0.05; others: P < 0.01) and social participation also tended to improve (P < 0.08). There was a significantly negative correlation between the initial Quality of Life and the changes in the Quality of Life (6 of the 8 components). In the all subjects, there was a significantly positive correlation between the changes in physical symptoms and the changes in VO2max/wt (r = 0.36, P < 0.05). In the dropout group, the FBS increased significantly (P < 0.05) but no other variables regarding the Quality of Life significantly changed after 2 months. In conclusion the above results suggest that short-term low intensity aerobic training in the present study can help improve the physiological indexes, VO2max and Quality of Life in middle-aged White Collar Workers and the observed improvement in the Quality of Life was also found to be greater in the subjects with a low Quality of Life than in those with a high Quality of Life.

Adult↗
PubMed1998

A combination therapy with simvastatin and ursodeoxycholic acid is more effective for cholesterol gallstone dissolution than is ursodeoxycholic acid monotherapy.

Inhibitors of 3-hydroxy,3-methylglutaryl coenzyme A (HMG-CoA) reductase have been reported to decrease the cholesterol saturation index (CSI) in duodenal bile in humans and to prevent formation of cholesterol gallstones in animal studies. We performed a prospective study to evaluate the role of HMG-CoA reductase inhibitors as gallstone-dissolving agents. Fifty patients with radiolucent gallstones in a gallbladder opacifying at drip infusion cholecystography were treated with either 10 mg/day simvastatin plus 600 mg/day ursodeoxycholic acid (group 1, n=26) or 600 mg/day ursodeoxycholic acid alone (group 2, n=24) for 12 months. The ratio of solitary to multiple gallstone cases was 21:29. Plasma lipid levels were assessed and ultrasonographic examination of the gallbladder was performed at baseline and at 3-month intervals during treatment. Duodenal bile sampling was performed in five patients in each group at baseline and after 12 months of treatment. Plasma cholesterol decreased significantly in group 1 but not in group 2. In solitary gallstone cases, no significant difference in dissolution rates was observed between groups 1 (3 of 9, 33%) and 2 (4 of 12, 33%). In contrast, the dissolution rate in multiple gallstone cases was significantly higher in group 1 (12 of 17, 71%) than in group 2 (3 of 12, 25%) (p < 0.01). Bile cholesterol saturation index was significantly decreased (p < 0.01) but did not significantly differ between the two groups. These results suggest that combination therapy with simvastatin and ursodeoxycholic acid is more effective for cholesterol gallstone dissolution than ursodeoxycholic acid monotherapy in patients with multiple gallstones.

Bile↗
PubMed1998

Blood pressure lowering effect of low intensity aerobic training in elderly hypertensive patients.

PURPOSE: The purpose of this investigation was to determine the effect of 9 months of low intensity aerobic training on blood pressure in elderly hypertensive patients who were receiving antihypertensive medication. METHODS: The training group (N = 13; mean age 75.4 +/- 5.4 yr) agreed to take part in physical training using a treadmill with an exercise intensity at the blood lactate threshold (LT) for 30 min three to six times a week for 9 months. The rest (N = 13; mean age 73.1 +/- 4.2 yr) served as controls. RESULTS: The resting systolic (-15 +/- 8 mm Hg), mean (-11 +/- 6 mm Hg), and diastolic blood pressures (-9 +/- 9 mm Hg) decreased significantly after 3 months of training and the blood pressure of all participants stabilized at a significantly lower level by the end of the study (9 months) in the training group, whereas no significant changes in blood pressure were found in the control group. Both the pretraining systolic and diastolic blood pressure of those recruited patients negatively correlated with those changes after the training (SBP: P < 0.01; DBP: P < 0.05, respectively). After 1 month of detraining in five patients, the blood pressure levels were similar to those in the pretraining state. The LT increased significantly in the training group (P < 0.01). CONCLUSION: In conclusion, an additional antihypertensive effect of mild aerobic training at the LT was confirmed in elderly patients receiving antihypertensive medication. The cessation of such training in five patients, however, resulted in a relatively rapid return to pretraining levels within a month.

Aged↗
PubMed1998

[Koch's phenomenon after BCG vaccination and the two-step tuberculin test in elementary school children].

In Japan, BCG vaccination, which covers more than 90% of infants, has been given according to the national immunization policy. Moreover, first-grade children in elementary school are screened with tuberculin skin test, and those who show negative reaction in the Japanese standard, i.e. size of erythema less than 10 mm, are re-vaccinated with BCG according to the Tuberculosis Prevention Law. However, since the incidence of tuberculosis among children below age 14 is as low as 1.5/100,000 in Japan, it is time to reconsider the BCG vaccination policy. As the first step to assess the efficiency of the present program, we observed the occurrence of Koch's phenomenon after BCG vaccination in elementary school children in Chiba City in 1995 and 1996, and we introduced the two-step tuberculin test to elementary school children in 1997. Among 180 BCG vaccinated children in 1995 and 1996, 168 (93.3%) had been vaccinated by 4-year of age. We could follow local reaction of BCG re-vaccination and observed Koch's phenomenon in 117 (69.6%, 95% C.I. of 62.7-76.6%). Among 92 tuberculin negative children in 1997, 85 (92.4%) had been vaccinated by 4-year of age. In the two-step tuberculin test program of 85 initial negative-reactors, 63 (74.1%, 95% C.I. of 64.8-83.4%) turned to positive by the second test. Those results suggest that more than 69% of tuberculin-negative school children who were vaccinated previously maintained immunity with BCG. Our studies raised a problem of the current BCG re-vaccination policy that depends on the result of tuberculin test. Due to the discrepancy between tuberculin allergy and immunity in tuberculosis, many school children may be given BCG vaccination unnecessarily. Taking into consideration the incidence of tuberculosis in children, discontinuation of BCG re-vaccination policy at elementary school entrance should be considered.

BCG Vaccine↗
PubMed1995

The effects of long-term low intensity aerobic training and detraining on serum lipid and lipoprotein concentrations in elderly men and women.

The effects of long-term low intensity aerobic training and detraining on serum lipid and lipoprotein concentrations were examined in 30 elderly men and women. These subjects were randomly divided into two groups. The training group [n = 15; 7 men and 8 women; mean age 75.5 (SD 5.6) years] agreed to take part in physical training using a treadmill with an exercise intensity at the blood lactate concentration threshold for 30 min 3-6 times a week for 9 months. The other group [n = 15; 7 men and 8 women; mean age 73.7 (SD 4.4) years] did not perform any particular physical training and was followed as the control. Following this training period the high density lipoprotein-cholesterol (HDL-C) had increased significantly (P < 0.01) while the total cholesterol (TC):HDL-C ratio had decreased significantly (P < 0.01) in the training group after 9 months but had not changed in the control group. The TC, triglyceride (TG) and low density lipoprotein-cholesterol (LDL-C) had not changed significantly in either group. No significant difference was seen between the groups throughout the period for TC. LDL-C or TG. There was, however, a significant correlation between the initial TC:HDL-C ratio and the change in the TC:HDL-C ratio following 3 months of training (P < 0.05). After 1 month of detraining in 5 patients, the HDL-C had decreased significantly (P < 0.05) while the TC:HDL-C had increased significantly in the training group (P < 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)

Aged↗
PubMed1992

[Ultrasonographic findings of abdominal tuberculous lymphadenitis].

Five patients with abdominal tuberculous lymphadenitis were studied by ultrasound. The final diagnosis of tuberculosis was based on open biopsy in 2 patients, neck lymph node biopsy in 1, needle biopsy under ultrasound control in 2. Low-echoic and iso-echoic abdominal lymph nodes were seen in all patients and a mixed echoic lymph node was found in one of them. Enlarged, round or oval, lymph nodes were conglomeratically observed along the common hepatic artery, in the hepatoduodenal ligament and along the abdominal aorta. The size of the lymph node was found to be 20-70 mm. In one case, compression of the portal trunk and the common bile duct due to a large lymph node was observed, and arterioportography showed hepatopetal collateral veins. In the other case, multiple mass lesions in the liver and the spleen were observed. In the 4 patients who were observed by ultrasound at 2 months after anti-tuberculosis therapy, enlarged lymph nodes decreased and 3 of them changed from low-echo to iso-echo in the echo pattern. Of the 4 patients who were followed for more than 4 months, lymph nodes disappeared in 2 at 4 months and in one at 12 months. The remaining patient showed residual nodes which decreased in half at 8 months. Ultrasound is now used commonly in the examination of the abdomen, and there are cases of abdominal lymph nodes swelling due to varied diseases. In this study, there were no characteristic ultrasonographic findings in abdominal tuberculous lymphadenitis. So, it is difficult to diagnose the cause of abdominal lymph node swelling by only ultrasound.(ABSTRACT TRUNCATED AT 250 WORDS)

Abdomen↗
PubMed1989

[Systolic time intervals in mitral valve prolapse syndrome].

Systolic time intervals (STI) were measured in 135 patients with mitral valve prolapse syndrome (MVP). These patients were categorized as Group II (no or trivial mitral regurgitation) and Group III (moderate or severe regurgitation). The controls consisted of 120 normal subjects (Group I). The Group II patients tended to have increased ETc and shortened PEP. The Group III patients tended to have prolonged Q-I and decreased QIIc and ETc, reflecting mitral regurgitation. It was suggested that autonomic nervous system, especially sympathetic nerve, may play a role in changes of STI of the Group II patients.

Adolescent↗
PubMed1988

[Flow imaging of the cardiovascular system using magnetic resonance imaging].

Blood flow images by magnetic resonance imaging (MRI) using a 0.25 T unit were evaluated for nine normal volunteers and 108 subjects with a variety of cardiovascular abnormalities. Using the non-gated short-spin echo (SE) technique, blood flow in the cardiovascular systems was not imaged in the normal volunteers. Using end-systolic and end-diastolic SE techniques for the normal subjects, blood flow in the cardiac chambers was not clearly imaged. Blood flow in the ascending aorta and aotric arch often did not appear in the gated SE images of the normal subjects. However, blood flow in the descending aorta was often observed in the gated SE images. Blood flow imaging was demonstrated by both non-gated and gated SE techniques in regions where blood flow was relatively slow; for example, in the left atrium of mitral stenosis, in an aortic aneurysm, in a false lumen of an aortic dissection, and in the left ventricle having old myocardial infarction. Using the non-gated inversion recovery (IR) technique, no blood flow was imaged in the cardiovascular system except in the left atrium of one case with mitral stenosis. Using the non-gated short SE technique, there was good correlation between the thrombus formation and the presence of blood flow images in the left atria of 17 patients with mitral stenosis, and in the aneurysmal portions of the aorta or in the false lumens of aortic dissection of 18 patients. It was suggested that mural thrombi in such diseases were related to the relatively slow blood flow. Blood flow imaging easily distinguished stagnant blood flow from mural thrombi using non-gated short SE, end-systolic SE, and IR techniques. Thus, blood flow imaging using MRI should become an important means of evaluating the cardiovascular system.

Adult↗