No abstract available.
Body Water* ; Kidney*

PURPOSE: A parallel imaging method provides us to improve temporal resolution to obtain three-dimensional (3D) MR images. The objective of this study was to optimize three 3D MRI techniques by adjusting 2D SESNE factors of the parallel imaging method in phantom and human brain. MATERIALS AND METHODS: With a 3 Tesla MRI system and an 8-channel phase-array sensitivity-encoding (SENSE) coil, three 3D MRI techniques of 3D T1-weighted imaging (3D T1WI), 3D T2-weighted imaging (3D T2WI) and 3D fluid attenuated inversion recovery (3D FLAIR) imaging were optimized with adjusting SESNE factors in a water phantom and three human brains. The 2D SENSE factor was applied on the phase-encoding and the slice-encoding directions. Signal-to-noise ratio(SNR), percent signal reduction rate(%R), and contrast-to-noise ratio(CNR) were calculated by using signal intensities obtained in specific regions-of-interest (ROI). RESULTS: In the phantom study, SENSE factor=3 was provided in 0.2% reduction of signals against without using SENSE with imaging within 5 minutes for 3D T1WI. SENSE factor=2 was provided in 0.98% signal reduction against without using SENSE with imaging within 5 minutes for 3D T2WI. SENSE factor=4 was provided in 0.2% signal reduction against without using SENSE with imaging around 6 minutes for 3D FLAIR. In the human brain study, SNR and CNR were higher with SENSE factors=3 than 4 for all three imaging techniques. CONCLUSION: This study was performed to optimize 2D SENSE factors in the three 3D MRI techniques that can be scanned in clinical time limitations with minimizing SNR reductions. Without compromising SNR and CNR, the optimum 2D SENSE factors were 3 and 4, yielding the scan time of about 5 to 6 minutes. Further studies are necessary to optimize 3D MRI techniques in other areas in human body.
Brain ; Human Body ; Humans ; Water

Hypematremia is a rare but important medical condition and is associated with mortality rate of 40 to 70%. However, little has been known about its prognostic factors or treatment guidlines. To evaluate the prognostic factors and the outcome following treatment, we reviewed 22 available medical records among twenty five hypernatremic patients (0.2%) in 12841 admissions at medical ward from January to December 1995. We defined hypernatremia as serum sodium concentration more than or equal to 150 mEq/L. Of these patients, two had hypematrernia at admission and the remaining patients became hypernatremic during admission. Mean peak serum sodium concentration was 158 (150-178) mEq/L and mean total body water deficit was 11.4 (6.7-21.3)%. Factors correlated with the development of hypernatremia were diverse and multiple, and the most frequent factor was diminished access to water. Mortality rate was 59%, but mortality was not correlated with age, correction rate of hyper-natremia, primary route of fluid loss, and the severity of hypernatremia or total body water deficit. Mortality rate was higher in patients whose serum sodium concentrations were below 130 mEq/L at admission (P<0.05). In our study, development of hypernatremia from initial hyponatremic state was significantly associated with poor outcome, and age, rapidity of correction, route of fluid loss, and the severity of hypernatremia or total body water deficit were not.
Body Water ; Humans ; Hypernatremia* ; Medical Records ; Mortality ; Sodium ; Water

In order to investigate whether the lowering of the intraocular pressure by the compression of the eyebaIl is accompanied by the decrease of water content of the vitreous, rabbit's left eyes were compressed with digital pressure of approximately 2 kg while the right eyes were left undisturbed. The vitreous body and lens were taken immediately after the animals were sacrificed by air injection and their water contents were calculated by weighing. The water contents of the vitreous and lens showed no significant changes in spite of profound faIl of intraocular pressure. It was concluded that the 5 minutes pressure on the eyeball was ineffective to reduce the vitreous volume.
Animals ; Intraocular Pressure ; Vitreous Body ; Water*

Chronic volume overload is associated with left ventricular hypertrophy and high cardiovascular mortality in patients undergoing dialysis. Therefore, estimating body fluid status is important in these patients. However, most dry-weight assessments are still performed clinically, while attempts have been made to measure the volume status and dry weight of patients undergoing dialysis using bioimpedance analysis (BIA). BIA uses the electrical properties of the human body to alternate current flow and measures resistance values to estimate body water content and composition. BIA is divided into single-frequency BIA, multi-frequency BIA, and bioimpedance spectroscopy (BIS) according to the number of frequencies used, and into whole-body and segmental BIA according to whether or not the whole body is divided into segments. Extracellular water (ECW), intracellular water, and total body water (TBW) contents can be measured with BIA. Dry weight can be estimated by measuring the volume overload of the patient through the ECW/TBW and ECW-to-body weight ratios. Other estimation methods include the normovolemia/hypervolemia slope method, a resistance-reactance (RXc) graph, overhydration measurements using a body composition monitor, and calf BIS. In this review, we will examine the principles of BIA, introduce various volume status measurement methods, and identify the optimal method for patients undergoing dialysis.
Body Composition ; Body Fluids ; Body Water ; Dialysis* ; Human Body ; Humans ; Hypertrophy, Left Ventricular ; Methods ; Mortality ; Spectrum Analysis ; Water

BACKGROUND: Bioelectrical impedance analysis (BIA) can be used to estimate body composition. To achieve the best results, the manufacturer's guidelines advise that individuals should restrict intake of food or caffeine, avoid vigorous exercise for 4 hours, and drink 2–4 glasses of water 2 hours before testing. We evaluated the appropriacy of drinking 2–4 glasses of water 2 hours before the BIA, as the validity of this indication has not been specifically demonstrated, by comparing intracellular water (ICW), extracellular water (ECW), total body water (TBW) in the fasting state, and after 1 and 2 hours of ingesting 500 mL of water.METHODS: Twenty-nine healthy adult men (n=10) and women (n=19) were recruited for the study. In the fasting state, the InBody 720 analyzer was used as multi-frequency (MF)-BIA and the output was recorded to determine the exact weight. Subsequently, Medinex BIA 450 analyzer was used as single-frequency (SF)-BIA, and the output was recorded. After drinking 500 mL of water 1 or 2 hours before assessment, the BIA tests were repeated as indicated above, and the ICW, ECW, TBW were compared by repeated measures ANOVA.RESULTS: SF-BIA measurements showed that compared to fasting state, the ICW decreased by approximately 0.56 L after 1 hour of drinking (P=0.001). The ECW was increased by about 0.62 L, 1 hour after drinking water compared to the fasting state (P=0.002). There were no significant differences between the results of BIA testing at 1 and 2 hours of fluid intake. The MF-BIA measurements indicated that testing after fasting, or 1 or 2 hours after fluid intake, did not result in significantly different ICW and ECW values. TBW showed no significant differences in the fasting state, or after 1 or 2 hours of fluid intake for both SF and MF.CONCLUSION: Several studies have shown that bioelectrical impedance should be measured in the fasting state. But not the food intake, drinking 500 mL of water may be permitted when measuring MF-BIA. However, for SF-BIA measurements, fluid intake resulted in an increase in the ECW level and a decrease in ICW.
Adult ; Body Composition ; Body Water ; Caffeine ; Drinking ; Drinking Water ; Eating ; Electric Impedance ; Eyeglasses ; Fasting ; Female ; Glass ; Humans ; Male ; Water

BACKGROUND: The kidney size is important in differentiating many renal diseases. Some studies have been reported about the normal kidney size in the foreign countries. However, no studies were performed by using ultrasonography in Korea. Therefore, we investigated the normal kidney length, the factors affecting the kidney length and the relationship of each other. METHODS: One thousand three hundred eighty eight healthy Koreans were scanned for the kidney length by ultrasonography and were measured for their body index(height, weight, body surface area, total body water, and fat free mass). We analyzed the association between kidney length and body index. RESULTS: Eight hundred four male and five hundred eighty four female were involved in this study and their mean age was 47.8+/-10.3 in male, 48.1+/-9.5 in female. 1) The average value of left and right kidney was 10.65+/-0.80cm, 10.50+/-0.78cm respectively, and the left kidney was greater than right one(P<0.01). 2) The difference between male and female was 10.77+/-0.79cm, 10.49+/-0.78cm respectively in the left kidney and 10.66+/-0.76cm, 10.27+/-0.75cm in the right kidney(P<0.01). 3) The aging process nearly does not affects the kidney size from 4th decade to 7th decade. However, the kidney size is getting smaller after 8th decade. 4) The correlation coefficient between the kidney size and height, weight, body surface area, total body water, fat free mass was 0.37, 0.41, 0.43, 0.37, 0.38(P<0.01) respectively. CONCLUSION: The kidney length showed normal distribution in normal Korean adult and the length greater than 12.36cm, smaller than 8.76cm means out of its range of normal(+/-2SD) irrespective of sex and position. The body surface area has the largest correlation with kidney size in both sex(r=0.38/0.44; left/right, P<0.01).
Adult* ; Aging ; Body Surface Area ; Body Water ; Body Weight ; Female ; Humans ; Kidney* ; Korea ; Male ; Ultrasonography*

BACKGROUND: It is necessary to measure total body water (TBW) in evaluation of the hemodialysis adequacy. Waston's equation has been used clinically. And it is important to measure adequate dry body weight to avoid fluid overloading after hemodialysis. But there was no objective method to measure dry body weight, it was estimated subjectively by clinicians (doctors and nurses). Multi-frequency bioelectrical impedance analysis (MFBIA) has emerged as a clinical tool of the measurement of total body water (TBW) and body fluid compartment (ICW, ECW). The purpose of this study is to investigate the correlation MFBIA-TBW and Watson equation, Then intracellular water (ICW)/extracellular water (ECW) ratio (I/E ratio) usefulness in the evaluation of dry body weight. METHODS: 20 HD patients treated 3 times/week and 21 sex and age adjusted normal control subjects were studied. We measuerd and compared MFBIA-TBW to Waston equation, estimate reproducibility MFBIA-TBW measurement. Then MFBIA-ECW, ICW and I/E ratio were measured and compared dialysis patients both pre- and post dialysis to control group. RESULTS: The correlation between Wastron-TBW and MFBIA-TBW for patients was 0.948 (p<0.001). The closeness of agreement between MFBIA-TBW and Waston-TBW is shown Bland-Altman plots. There was no difference in post-dialysis patient's ICW/ECW ratio compared to control group. CONCLUSION: MFBIA is useful tool for dialysis patients' TBW measurements. Also ICW/ECW ratio measurement by MFBIA may be used to estimate the adequate ultrafiltration.
Body Fluid Compartments ; Body Water* ; Body Weight ; Dialysis ; Electric Impedance* ; Humans ; Renal Dialysis* ; Ultrafiltration

OBJECTIVETo evaluate a calculating method of wound water loss (WWL) in hospitalized burn patients.

METHODSEighty-five adult burn patients with total burn area over 50% were enrolled in the study. The WWL formula after shock stage (after 3rd postburn day) was given as: WWL (ml/%/kg/24 h) = [input (ml/24 h)-urine output (ml/24 h)-500 ml] / actual burn wound area(%) / body weight (kg). The result was compared with that determined by other formulas such as Davies, S.M.S.P and Lamke and palm rule.

RESULTSThe calculated daily WWL in burn patients after shock stage was found out to be 0.9 +/- 0.1 ml/%/kg/24 h by this method. This figure is comparable with that calculated by several different methods. Palm rule could be simply applied in the patients with body weight around 60 kg.

CONCLUSIONThis method and palm rule were proved to be simple and practical for the calculation of WWL in burn patients, which could be applied in clinical work.

Adolescent ; Adult ; Algorithms ; Body Water ; metabolism ; Burns ; metabolism ; physiopathology ; Female ; Humans ; Male ; Middle Aged ; Water Loss, Insensible ; Water-Electrolyte Imbalance

The volume perception of water according to cup shape was examined in female college students divided into a normal weight group (<23 body mass index, n=51) and an overweight group (> or =23 body mass index, n=48). The perceived water volume was recorded by participants after they observed the water volume in cups with different shape (highball and tumbler) and with different base height (high base and low base), which contained the same amount of water (150 ml). The normal weight group perceived a water volume of 238.5 ml (highball) and 201.6 ml (tumbler) for the high base cups. The overweight group perceived a volume of 245.6 ml (highball) and 188.8 ml (tumbler). For the low base cups, the normal weight group perceived a water volume of 207.8 ml (highball) and 104.1 ml (tumbler). The overweight group perceived a volume of 202.2 ml (highball) and 100.4 ml (tumbler). Both the normal weight and overweight groups perceived significantly more liquid in the highball cups compared to the tumbler cups. In addition, both groups perceived significantly more liquid in the high base cups compared to the low base cups. However, there were no significant differences in the estimated variance of perceived volume between the normal weight and overweight groups according to the cup shape and cup base height. In conclusion, cup shape and base height potentially affects volume perception. Therefore, modifying cup shape may be used in a weight control program to help control caloric beverage consumption.
Beverages ; Body Mass Index ; Female* ; Humans ; Overweight* ; Water