Normal prostate volume radiology

Following the MR examination the brains of the animals were analyzed for EM. There was a normal prostate volume radiology from the slow to the fast component at min time point. The water signal was increasing by 4. The results of the E.

Conclusion: The unexpected volume fraction changes i. It may suggest that ADC decrease in stroke, in contrast to general presumptions, cannot be explained only by water shift from extra to intracellular space i.

A biexponential DWI study in rat brain intracellular oedema

All rights reserved. It was pointed out that even without compartmentation the biexponential signal decay is still present [4] and it can also be observed in a single cell [5]. Many speculations have been put forward about the two components: sol and gel state of water [6], bulk water and membrane bound water [7], free water and bound water in the hydration shells of the macromolecules [4]. E-mail address: roy. Because these speculations could not be proven so far, the biexponential model itself was questioned [8] arguing about a continuous, broad distribution of ADC values [9].

Thus other mathematical models have been proposed to describe the diffusion and the consequent signal decay in Diffusion weighted imaging DWI : diffusional kurtosis imaging Taylor expansion of the logarithm of signal decay [8,10,11], inverse Laplace transformation [9], and stretched exponential [12] etc.

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The aim of this study is to examine the changes in MR parameters derived from DWI biexponential analysis in an in vivo intracellular brain oedema model. Electron microscopy was also applied in order to shed more light on the morphological background of MR related observations.

Biexponential DWI analysis may help to understand water movements in brain oedema. The DWI results of pure artrózis kezelésére készülékkel oedema were compared normal prostate volume radiology those obtained in stroke, in which intracellular oedema i.

Steier et al. Materials and methods 2. Experimental protocol Ten male Wistar rats Charls Rivers, local distributor weighing — g were used. All procedures were done according to the University research ethical guidelines. The animals were endotrachelly intubated and anaesthesia was maintained at 1.

Following establishment of a base-line measurement, the water loading took place. Correct IP normal prostate volume radiology normal prostate volume radiology was visualized with an MR measurement. Blood was acquired by way of cardiac puncture for serum analysis of sodium and potassium ion selective electrode as well as plasma osmolarity vapour pressure osmometer.

Following 24 h, the brains of the animals were removed and analyzed for electron microscopy EM. The exact method of EM analysis is described previously [14]. Magnetic resonance normal prostate volume radiology 3. The body coil was used for excitation and a commercially available loop of RF coil, having an inner diameter of 40 mm was used for the signal acquisition Siemens Medical Solutions, Erlangen, Germany.

For base-line establishment, 3 diffusion-weighted and spectroscopy measurements were done. The voxel was adjusted to each animal in order to cover the brain as much as possible The average voxel size was 13 mm × 10 mm × 5 mm.

In this way only the unsuppressed water signal was recorded. Freehand regions of interests ROIs were drawn on diffusion weighted images covering both sides of the cortex. Parameters were calculated according to the selected region.

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For the water signal evaluation standard spectroscopy software was used on a Siemens Leonardo workstation. For signal processing only Fourier transformation was applied. The changes in ADC and water signal are referenced to the average of the initial three base line measurements [15]. Values are expressed as means ± standard deviation. Statistical analysis was done using two-tailed equal distribution paired Student t-tests.

MULTIPARAMETRIC MR IMAGING OF PROSTATE TUMORS: PI-RADS V.2.1

Results 3. Changes normal prostate volume radiology serum osmolarity and sodium The IP injection of the dextrose solution caused a severe hyponatraemia reaching a serum sodium level of This hyponatremia was accompanied with a decrease of serum osmolarity to levels of Following the R. By evaluating the volume fraction contributions of the slow Pslow and fast P-fast components to the ADC-mono we realize that while the P-fast exhibits a tendency to increase, the P-slow shows the opposite tendency to decline.

The changes in the Pfast and P-slow of Changes in water signal The results of the spectroscopy measurements showed that the water signal was increasing. It had increased by 2. The water signal continued to elevate up until the min time point. Reaching an increase of 4. Electron microscope observations In the examined areas of both the temporal cortex and the caudo-putamen, with negligible exceptions, the excess water was found in astrocytes i.

The bulk of excess water was present around arterioles Fig. In several places, molecular remnants of the disintegrated organelles of swollen astrocytes selfe-assembled into regular Normal prostate volume normal prostate volume radiology. Discussion The biexponential approach is a robust model that gives consistent ADCs and volume fraction values in the brain tissue and appears to elbon ízületi gyógyszer insensitive to an inversion pulse T1magnetization transfer, extension of echo time T2 [1,3].

However, a recent paper suggests that ADC-slow increases by Fig. The ADC values were normalized to the average of the normal prostate volume radiology three base-line measurements. Average values of the fast component of ADC in the rat cerebral cortex throughout the MR measurement protocol. The predominance of normal prostate volume radiology fast volume fraction i. These characteristics of the bi-exponential approach may substantiate that it will have diagnostic value in the daily clinical practice [16—18] similar to the mono-exponential approach in the low b-value range.

normal prostate volume radiology nem hagyományos módszerek az ízületek kezelésére

The intracellular oedema created in this study resulted in volume fractions that are unexpected. In contrast to stroke [1,4,17], P-fast increased. However there are substantial differences that can explain the discrepancy. In intracellular oedema i.

There is no tissue necrosis that might result in degradation of macromolecules and dysfunction of membrane pumps and channels. Therefore, based on our experiments it can be deduced that the intracellular oedema alone i.

Our results also contradict in vitro studies in which cells were swollen i. Average values of the slow component of ADC in the rat cerebral cortex throughout the MR measurement protocol. Percentages of the fast and slow components of ADC. Average percentages of the fast P-fast krónikus bokaízület gyulladás slow P-slow components of ADC in the rat cerebral cortex throughout the MR measurement protocol.

The percentages were normalized to the average of the initial three base-line measurements. Following the intraperitoneal injection IPI the ADC percentages of the fast and slow components exhibit a tendency to increase and decrease respectively. There are several limitations that should be mentioned about the in vitro studies: i The measurements were carried out normal prostate volume radiology room temperature that would considerably slow down the enzymatic processes and conformation of the proteins might change dramatically.

It is well known from in vivo studies that a radical ADC decrease is almost immediate 2—3 min if anoxia-ischemia takes place [24]. Unfortunately normal prostate volume radiology ADC values are not comparable due to the application of room temperature. Table 2 summarizes the results of biexponential diffusion measurements in different pathological conditions. It is clear from Table 2 that ADC-fast would have diagnostic value, since it decreases in intracellular oedema i.

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The latter is obvious also in muscle oedema in which the presumed extracellular water increase causes P-fast and ADC-fast elevations [19]. Average diffusion weighted signal decay originating from rat brains before oedema induction. The error bars are hardly visible because of the low standard deviations. The noise level is demonstrated by a dotted line.

Water signal.

normal prostate volume radiology gyógyszer vállbetegség

The evolution of the total brain average water signal values throughout the MR measurement protocol. The water signal values were normalized to the average of the initial three base-line measurements. Following the intraperitonel injection IPI the water signal was increasing. The other parameter that would have diagnostic value is P-fast. It is hypothesized that the fast component represents free, bulk water that would be the best candidate to be eliminated from oedematous tissue.

The only detail that seemingly does not support the proposed theory is that the core region normal prostate volume radiology cold injury shows different behavior Table 2 : P-fast decreases despite the presence of vasogenic oedema. However it should be noted that the core of the cold injury contains disintegrated cells [4], thus necrosis and vasogenic oedema are present at the same location.

These two antagonistic effects on P-fast would result in a marked decrease, if necrosis—apoptosis are more dominant than vasogenicextracellular oedema. In the penumbra region of cold injury that presumably contains living tissue with extracellular oedema [16], the ADC-fast and P-fast are also increased as it can be expected.

There are limitations also in our study; a long echo and diffusion times were applied due to the hardware restrictions of a clinical scanner. In our case, the ADC parameters were higher, while the volume fractions are lower than those obtained by Niendorf et al. However, the difference may be explained by the following facts: i trace weighting was used in our study vs.

Despite these limi- Table 2 DWI biexponential parameters in different pathologies. Electron micrograph. A long thin arrow points to a pericyte, a short thin arrow to an endothelial cell, and a short thick arrow to the basement membrane. The arrows mark torn ends of the outer membranes of astrocytic processes.

An arrow points to the extracellular space between the outer membranes of the two astrocytic endfeet. Other mathematical models e. In conclusion, unexpected volume fraction changes were detected in hypotonic oedema. These, appear to be substantially different from those observed in stroke.

It may suggest that ADC normal prostate volume radiology in stroke, in contrast to general presumptions and radiology textbook data, cannot be explained only by water shift from extra to intracellular space i. Perhaps other mechanisms elicit the ADC decrease such as decreased cytoplasmic streaming, membrane pump dysfunctions, changes in physical state of water i.

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