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Non-invasive identification and differentiation of myocardial diseases represents the primary objectives of cardiac magnetic resonance (CMR) longitudinal relaxation time (T1) and extracellular volume (ECV) mapping. Given the fact that myocardial T1 and ECV values overlap throughout and within left ventricular phenotypes, a central issue to be addressed is whether and to what extent myocardial T1 and ECV mapping provides additional or superior diagnostic information to standard CMR imaging, and whether native T1 mapping could be employed as a non-contrast alternative to late gadolinium enhancement (LE) imaging. The present review aims to summarize physiological and pathophysiological alterations in native T1 and ECV values and summarized myocardial T1 and ECV alterations associated with cardiac diseases to support the translation of research findings into routine CMR imaging., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

While an enormous number of studies have documented pathological alterations of the myocardial native longitudinal relaxation time (T1) and the fraction of the extracellular myocardial volume (ECV), it has also become clear that continuously evolving T1 mapping sequence, acquisition and evaluation techniques have a substantial impact on quantitative results, making the translation of reported findings into routine clinical use particularly challenging. To provide a basis for the discussion of pathological myocardial T1 and ECV alterations, the present review aims to summarize the methodological aspects of myocardial T1 mapping along with technical and physiological factors influencing results and normal ranges of myocardial native T1 and ECV reported across studies., (Copyright © 2018 The Authors. Published by Elsevier B.V. All rights reserved.)

Objectives: To analyze alterations in left ventricular (LV) myocardial T1 times in patients with pulmonary hypertension (PH) and to investigate their associations with ventricular function, mass, geometry and hemodynamics., Methods: Fifty-eight patients with suspected PH underwent right heart catheterization (RHC) and 3T cardiac magnetic resonance imaging. Ventricular function, geometry and mass were derived from cine real-time short-axis images. Myocardial T1 maps were acquired by a prototype modified Look-Locker inversion-recovery sequence in short-axis orientations. LV global, segmental and ventricular insertion point (VIP) T1 times were evaluated manually and corrected for blood T1., Results: Septal, lateral, global and VIP T1 times were significantly higher in PH than in non-PH subjects (septal, 1249 ± 58 ms vs. 1186 ± 33 ms, p < 0.0001; lateral, 1190 ± 45 ms vs. 1150 ± 33 ms, p = 0.0003; global, 1220 ± 52 ms vs. 1171 ± 29 ms, p < 0.0001; VIP, 1298 ± 78 ms vs. 1193 ± 31 ms, p < 0.0001). In PH, LV eccentricity index was the strongest linear predictor of VIP T1 (r = 0.72). Septal, lateral and global T1 showed strong correlations with VIP T1 (r = 0.81, r = 0.59 and r = 0.75, respectively)., Conclusions: In patients with PH, T1 times in VIPs and in the entire LV myocardium are elevated. LV eccentricity strongly correlates with VIP T1 time, which in turn is strongly associated with T1 time changes in the entire LV myocardium., Key Points: • Native T1 mapping detects left ventricular myocardial alterations in pulmonary hypertension • In pulmonary hypertension, native T1 times at ventricular insertion points are increased • These T1 times correlate strongly with left ventricular eccentricity • In pulmonary hypertension, global and segmental myocardial T1 times are increased • Global, segmental and ventricular insertion point T1 times are strongly correlated.

Background: The hypertensive deoxy-corticosterone acetate (DOCA)-salt-treated pig (hereafter, DOCA pig) was recently introduced as large animal model for early-stage heart failure with preserved ejection fraction (HFpEF). The aim of the present study was to evaluate cardiovascular magnetic resonance (CMR) of DOCA pigs and weight-matched control pigs to characterize ventricular, atrial and myocardial structure and function of this phenotype model., Methods: Five anesthetized DOCA and seven control pigs underwent 3 T CMR at rest and during dobutamine stress. Left ventricular/atrial (LV/LA) function and myocardial mass (LVMM), strains and torsion were evaluated from (tagged) cine imaging. 4D phase-contrast measurements were used to assess blood flow and peak velocities, including transmitral early-diastolic (E) and myocardial tissue (E') velocities and coronary sinus blood flow. Myocardial perfusion reserve was estimated from stress-to-rest time-averaged coronary sinus flow. Global native myocardial T1 times were derived from prototype modified Look-Locker inversion-recovery (MOLLI) short-axis T1 maps. After in-vivo measurements, transmural biopsies were collected for stereological evaluation including the volume fractions of interstitium (V V (int/LV)) and collagen (V V (coll/LV)). Rest, stress, and stress-to-rest differences of cardiac and myocardial parameters in DOCA and control animals were compared by t-test., Results: In DOCA pigs LVMM (p < 0.001) and LV wall-thickness (end-systole/end-diastole, p = 0.003/p = 0.007) were elevated. During stress, increase of LV ejection-fraction and decrease of end-systolic volume accounted for normal contractility reserves in DOCA and control pigs. Rest-to-stress differences of cardiac index (p = 0.040) and end-diastolic volume (p = 0.042) were documented. Maximal (p = 0.042) and minimal (p = 0.012) LA volumes in DOCA pigs were elevated at rest; total LA ejection-fraction decreased during stress (p = 0.006). E' was lower in DOCA pigs, corresponding to higher E/E' at rest (p = 0.013) and stress (p = 0.026). Myocardial perfusion reserve was reduced in DOCA pigs (p = 0.031). T1-times and V V (int/LV) did not differ between groups, whereas V V (coll/LV) levels were higher in DOCA pigs (p = 0.044)., Conclusions: LA enlargement, E' and E/E' were the markers that showed the most pronounced differences between DOCA and control pigs at rest. Inadequate increase of myocardial perfusion reserve during stress might represent a metrics for early-stage HFpEF. Myocardial T1 mapping could not detect elevated levels of myocardial collagen in this model., Trial Registration: The study was approved by the local Bioethics Committee of Vienna, Austria (BMWF-66.010/0091-II/3b/2013).

Background: In patients with pulmonary hypertension (PH), duration of vortical blood flow along the main pulmonary artery enables estimation of the mean pulmonary arterial pressure (mPAP) non-invasively. It remains to date not known, if this method is applicable in patients with pulmonary arterial hypertension (PAH) and abnormal aortic-to-pulmonary shunting., Case Presentation: The present case analyzes the effect of a patent ductus arteriosus (PDA) on pulmonary artery flow patterns in PAH (mPAP from right heart catheterization, 75 mmHg). PH-associated vortical blood flow, which is typically observed rotating in a clockwise direction when viewed in right ventricular outflow tract orientation, was found nested in PDA left-to-right shunting. Even though rotating counter-clockwise, duration of vortical flow translated into correct non-invasive mPAP estimate., Conclusions: This case indicates that PH-associated vortex rotation is not restricted to clockwise direction, and that vortex-based estimation of elevated mPAP might also be feasible in patients with PAH and PDA.

Pulmonary hypertension (PH) is a life-threatening, multifactorial pathophysiological haemodynamic condition, diagnosed when the mean pulmonary arterial pressure equals or exceeds 25 mmHg at rest during right heart catheterization. Cardiac MRI, in general, and MR phase-contrast (PC) imaging, in particular, have emerged as potential techniques for the standardized assessment of cardiovascular function, morphology and haemodynamics in PH. Allowing the quantification and characterization of macroscopic cardiovascular blood flow, MR PC imaging offers non-invasive evaluation of haemodynamic alterations associated with PH. Techniques used to study the PH include both the routine two-dimensional (2D) approach measuring predominant velocities through an acquisition plane and the rapidly evolving four-dimensional (4D) PC imaging, which enables the assessment of the complete time-resolved, three-directional blood-flow velocity field in a volume. Numerous parameters such as pulmonary arterial mean velocity, vessel distensibility, flow acceleration time and volume and tricuspid regurgitation peak velocity, as well as the duration and onset of vortical blood flow in the main pulmonary artery, have been explored to either diagnose PH or find non-invasive correlates to right heart catheter parameters. Furthermore, PC imaging-based analysis of pulmonary arterial pulse-wave velocities, wall shear stress and kinetic energy losses grants novel insights into cardiopulmonary remodelling in PH. This review aimed to outline the current applications of 2D and 4D PC imaging in PH and show why this technique has the potential to contribute significantly to early diagnosis and characterization of PH.

Purpose: To approximate the functional relationship between invasively measured mean pulmonary arterial pressure (mPAP) and the phase-contrast magnetic resonance (MR) imaging-derived duration of vortical blood flow along the main pulmonary artery and to analyze its applicability for noninvasive diagnosis of pulmonary hypertension (PH) and borderline mPAP., Materials and Methods: The local ethics review board approved this prospective study of 145 patients suspected of having PH (69 patients with PH, 19 patients with borderline mPAP, and 57 patients with normal mPAP) who underwent right heart catheterization (RHC) and three-directional phase-contrast MR imaging of the main pulmonary artery. Velocity fields were viewed with dedicated software and evaluated for the duration of vortical blood flow in the main pulmonary artery (tvortex, the percentage of cardiac phases with vortex present). The relationship between mPAP at RHC and tvortex was assessed by means of a segmented linear regression model, and by Bland-Altman and receiver operating characteristic curve analyses., Results: The relationship between mPAP and tvortex was described adequately (R(2) = 0.95) as linearly increasing, from tvortex of 0% (mPAP ≤ 16.0 mm Hg) with a slope of 1.59% per millimeter of mercury. The standard deviation between mPAP values derived from RHC and those estimated by using tvortex was 3.9 mm Hg. The area under the curve for tvortex-based diagnosis of PH was 0.994 (95% confidence interval [CI]: 0.982, 0.998), and the calculated PH cut-off value (tvortex ≥ 14.3%) resulted in sensitivity of 0.97 (95% CI: 0.90, 0.99) and specificity of 0.96 (95% CI: 0.89, 0.99). Vortical blood flow with tvortex less than 14.3% was specific for borderline mPAP., Conclusion: Duration of vortical blood flow in the main pulmonary artery that is determined by using phase-contrast MR imaging allows accurate estimation of elevated mPAP and diagnosis of PH. Clinical trial registration no. NCT00575692.

Purpose: To introduce blood normalization for myocardial T1 values at magnetic resonance (MR) imaging and to evaluate regional differences between systolic and diastolic myocardial T1 values in healthy subjects., Materials and Methods: This prospective study (ClinicalTrials.gov identification number, NCT01728597) was approved by the institutional review board, and volunteer informed consent was obtained. Forty healthy subjects (20 women; age range, 20-35 years) underwent electrocardiographically gated 1.5-T MR imaging. A modified Look-Locker inversion recovery sequence was used to acquire myocardial T1 maps in systole and diastole. Regional T1 values were evaluated in 16 myocardial segments; blood T1 was derived from the blood pool in the center of the left ventricular cavity. Linear regression slopes between myocardial and blood T1 values were used to normalize myocardial T1 to the mean blood T1 of the study population. Mean T1 values were compared by using the t test, with P < .05 considered to indicate a significant difference., Results: Mean myocardial T1 (984 msec ± 28 [standard deviation] in diastole, 959 msec ± 21 in systole) and all segmental T1 values between diastole and systole differed significantly (P < .001). Blood T1 correlated well with segmental myocardial T1 (R = 0.73 for diastole, R = 0.72 for systole). After normalization to blood T1, significant sex differences in myocardial T1 disappeared and variances in mean myocardial T1 decreased. Blood-normalized diastolic and systolic myocardial T1 values correlated strongly with each other on segmental (r = 0.72) and global (r = 0.89) levels. Subregional myocardial T1 distribution characteristics in diastole were similar to those in systole., Conclusion: In normal myocardium, diastolic and systolic myocardial T1 values differ significantly but correlate strongly. Blood normalization eliminates sex differences in myocardial T1 values and reduces their variability.

Objectives: To assess the correlation of relative hepatic enhancement (RHE), relative renal enhancement (RRE) and liver to kidneys enhancement ratio (LKR) with serum hepatic enzyme levels and eGFR in Gd-EOB-DTPA enhanced MRI of the liver and to assess threshold levels for predicting enhancement of the liver parenchyma., Methods: Data of 75 patients who underwent Gd-EOB-DTPA enhanced MRI of the liver were collected. Images were obtained before contrast injection, during the early arterial phase, late arterial phase, venous phase, delayed phase, and hepatobiliary phase which was 20 min after Gd-EOB-DTPA administration. Signal intensity of the liver and the kidneys in all phases was defined using region-of-interest measurements for relative enhancement calculation. Serum hepatic enzyme levels and eGFR were available in all patients. Spearman correlation test was used to test the correlation of RHE, RRE and LKR with serum hepatic enzyme levels and eGFR., Results: In the hepatobiliary phase all serum hepatic enzymes were significantly correlated with RHE; total bilirubin (TBIL) and cholin esterase (CHE) showed strongest correlations. TBIL and CHE were significantly correlated with RRE in the arterial phases. TBIL and CHE were significantly correlated with LKR in the arterial phase and hepatobiliary phase. eGFR showed no correlation., Conclusions: In Gd-EOB-DTPA enhanced MRI, TBIL and CHE levels may predict RHE, RRE and LKR., (Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.)

Background: Even though intra-cardiac cystic lesions are extremely unusual in adults, they should be considered in the differential diagnosis of patients presenting with valvular masses. Cardiac magnetic resonance imaging has emerged as modality of choice for non-invasive characterization of cardiac masses., Case Presentation: We report a case of an intra-cardiac mass of the mitral valve in a 51-year old male, detected by echocardiography after transient ischemic attack and retinal artery occlusion. Cardiac magnetic resonance (CMR) imaging was performed at 3 T to evaluate and characterize the lesion prior to surgery. Diagnosis of a calcified left-ventricular pseudocyst of the mitral valve was confirmed by histological evaluation., Conclusions: This case presents the unusual finding of contrast uptake in an intra-cardiac cystic lesion and points to the potential of T1 and T2 mapping for assisting in the characterization and diagnosis of intra-cardiac masses by CMR.

Purpose: Three-dimensional (3D) magnetic resonance phase contrast imaging (PC-MRI) allows non-invasive diagnosis of pulmonary hypertension (PH) and estimation of elevated mean pulmonary arterial pressure (mPAP) based on vortical motion of blood in the main pulmonary artery. The purpose of the present study was to compare the presence and duration of PH-associated vortices derived from different flow visualization techniques with special respect to their performance for non-invasive assessment of elevated mPAP and diagnosis of PH., Methods: Fifty patients with suspected PH (23 patients with and 27 without PH) were investigated by right heart catheterization and time-resolved PC-MRI of the main pulmonary artery. PC-MRI data were visualized with dedicated prototype software, providing 3D vector, multi-planar reformatted (MPR) 2D vector, streamline, and particle trace representation of flow patterns. Persistence of PH-associated vortical blood flow (tvortex) was evaluated with all visualization techniques. Dependencies of tvortex on visualization techniques were analyzed by means of correlation and receiver operating characteristic (ROC) curve analysis., Results: tvortex values from 3D vector visualization correlated strongly with those from other visualization techniques (r = 0.98, 0.98 and 0.97 for MPR, streamline and particle trace visualization, respectively). Areas under ROC curves for diagnosis of PH based on tvortex did not differ significantly and were 0.998 for 3D vector, MPR vector and particle trace visualization and 0.999 for streamline visualization. Correlations between elevated mPAP and tvortex in patients with PH were r = 0.96, 0.93, 0.95 and 0.92 for 3D vector, MPR vector, streamline and particle trace visualization, respectively. Corresponding standard deviations from the linear regression lines ranged between 3 and 4 mmHg., Conclusion: 3D vector, MPR vector, streamline as well as particle trace visualization of time-resolved 3D PC-MRI data of the main pulmonary artery can be employed for accurate vortex-based diagnosis of PH and estimation of elevated mPAP.

Background: Recommended by current guidelines, red blood cell (RBC) temperature should not exceed 10°C during transport. Since warming is a generically three-dimensional process that is not homogeneous, it is necessary to clarify the term "temperature during warming." The purpose of this study was therefore to investigate laws and relations between surface, mean, and core temperature and the corresponding times when they exceed 10°C during warm-up., Study Design and Methods: Time-resolved three-dimensional temperature distributions of 53 resuspended RBC units (mean volume, 253 ± 17 mL) were measured noninvasively by magnetic resonance thermometry. Warm-up temperature maps were visualized and analyzed by dedicated software., Results: Mean times when surface, mean, and core temperature exceeded 10°C were 16 ± 4, 24 ± 5, and 36 ± 7 minutes, respectively. Times strongly correlated with each other (r = 0.78-0.95) and their variances mainly depended on RBC storage temperature and RBC pouch width (R(2)  = 0.81-0.89). Measured mean temperature time courses were well described by a lumped capacitive model of heat transfer with a sample width-dependent time constant τ(RBC)  = 56.3 ± 3.5 minutes (mean R(2)  = 0.996)., Conclusion: Times when RBC surface, mean, and core temperature exceed 10°C can be estimated from each other. Moreover RBC mean temperature can be calculated for arbitrary storage and ambient temperatures. Findings might serve as a helpful tool in RBC temperature monitoring., (© 2012 American Association of Blood Banks.)

Purpose: Temperature is a key measure in human red blood cell concentrate (RBC) quality control. A precise description of transient temperature distributions in RBC units removed from steady storage exposed to ambient temperature is at present unknown. Magnetic resonance thermometry was employed to visualize and analyse RBC warm up processes, to describe time courses of RBC mean, surface and core temperatures by an analytical model, and to determine and investigate corresponding model parameters., Methods: Warm-up processes of 47 RBC units stored at 1-6°C and exposed to 21.25°C ambient temperature were investigated by proton resonance frequency thermometry. Temperature distributions were visualized and analysed with dedicated software allowing derivation of RBC mean, surface and core temperature-time courses during warm up. Time-dependence of mean temperature was assumed to fulfil a lumped capacitive model of heat transfer. Time courses of relative surface and core temperature changes to ambient temperature were similarly assumed to follow shifted exponential decays characterized by a time constant and a relative time shift, respectively., Results: The lumped capacitive model of heat transfer and shifted exponential decays described time-dependence of mean, surface and core temperatures close to perfect (mean R(2) were 0.999±0.001, 0.996±0.004 and 0.998±0.002, respectively). Mean time constants were τmean = 55.3±3.7 min, τsurface = 41.4±2.9 min and τcore = 76.8±7.1 min, mean relative time shifts were Δsurface = 0.07±0.02 and Δcore = 0.04±0.01. None of the constants correlated significantly with temperature differences between ambient and storage temperature., Conclusion: Lumped capacitive model of heat transfer and shifted exponential decays represent simple analytical formulas to describe transient mean, surface and core temperatures of RBC during warm up, which might be a helpful tool in RBC temperature monitoring and quality control. Independence of constants on differences between ambient and storage temperature suggests validity of models for arbitrary storage and ambient temperatures.

Background: Radiofrequency identification (RFID) technology is emerging as one of the most pervasive computing technologies due to its broad applicability. Storage of red blood cells (RBCs) is a routine procedure worldwide. Depending on the additive solution, RBCs can be stored at 4 ± 2°C up to 49 days. To support the decision of discarding or further using a blood product, temperature measurement of each unit could be provided by RFID application. The safety evaluation of RFID devices was demonstrated in a regulatory agency required study. It has been concluded in limit tests that high frequency-based RFID technology performed safely for blood products; therefore, a longer exposure of radiofrequency (RF) energy on blood units was performed in this study to detect any biologic effects in RBC samples., Study Design and Methods: Buffy coat-depleted, in line-filtered RBCs were used as standard products in all tests. Various variables like pH, potassium, glucose, lactate, hemoglobin (Hb), hematocrit, free Hb, and hemolysis rate were measured in a test group with RFID tags placed on their surface and continuously radiated with 13.56-MHz RFID reader radiation for 42 days while stored at 4 ± 2°C and compared to a control group by two-sample t test., Results: In both groups glucose and pH levels decreased while lactate, free Hb, and potassium increased within the expected levels. The hemolysis rate showed increase after the 25th day but remained below the maximum acceptable threshold of 0.8%., Conclusion: It is feasible to implement RFID-enabled processes, without detecting any known biologic effects of longer exposure of RF energy on the quality of RBCs., (© 2011 American Association of Blood Banks.)

Pulmonary artery intimal sarcoma is a rare tumor of the cardiovascular system. Intimal sarcoma of the pulmonary valve itself has not been described. Embolization into pulmonary arteries originating from the pulmonary valve intimal sarcoma can mimic chronic thromboembolic pulmonary hypertension and mislead the diagnosis. We present and discuss a patient initially diagnosed as chronic thromboembolic pulmonary hypertension, treated by pulmonary endarterectomy. After 24 months, a tumor of the pulmonary valve was detected by echocardiography. The patient underwent removal and replacement of the pulmonary valve. Histology revealed pulmonary valve intimal sarcoma., (Copyright (c) 2010 The Society of Thoracic Surgeons. Published by Elsevier Inc. All rights reserved.)

Background: Pulmonary hypertension is a disease characterized by an elevation in pulmonary arterial pressure that is diagnosed invasively via right heart catheterization. Such pathological altered pressures in the pulmonary vascular system should lead to changes in blood flow patterns in the main pulmonary artery., Methods and Results: Forty-eight subjects (22 with manifest pulmonary hypertension, 13 with latent pulmonary hypertension, and 13 normal control subjects) underwent time-resolved 3D magnetic resonance phase-contrast imaging of the main pulmonary artery. Velocity fields that resulted from measurements were calculated, visualized, and analyzed with dedicated software. Main findings were as follows: (1) Manifest pulmonary hypertension coincides with the appearance of a vortex of blood flow in the main pulmonary artery (sensitivity and specificity of 1.00, 95% confidence intervals of 0.84 to 1.00 and 0.87 to 1.00, respectively), and (2) the relative period of existence of the vortex correlates significantly with mean pulmonary arterial pressure at rest (correlation coefficient of 0.94). To test the diagnostic performance of the vortex criterion, we furthermore investigated 55 patients in a blinded prospective study (22 with manifest pulmonary hypertension, 32 with latent pulmonary hypertension, and 1 healthy subject), which resulted in a sensitivity of 1.00 and specificity of 0.91 (95% confidence intervals of 0.84 to 1.00 and 0.76 to 0.98, respectively). Comparison of catheter-derived mean pulmonary artery pressure measurements and calculated mean pulmonary artery pressure values resulted in a standard deviation of differences of 3.6 mm Hg., Conclusions: Vortices of blood flow in the main pulmonary artery enable the identification of manifest pulmonary hypertension. Elevated mean pulmonary arterial pressures can be measured from the period of vortex existence.

Pulmonary hypertension is a life-threatening chronic disorder of the pulmonary circulation. Elevated pressure and resistance in the pulmonary vessels lead to progressive right heart failure which results in functional limitations and ultimately the death of most patients. Thus, the monitoring of right ventricular (RV) function is of great importance. Cardiac magnetic resonance imaging (cardiac MRI) has several advantages over other imaging methods. The use of cine acquisition techniques allows precise description of characteristic volumetric and functional variables, such as right ventricular volumes, muscle mass, stroke volume, ejection fraction, or cardiac output. Impaired right ventricular contractility and function have also been assessed using measures like ventricular septal bowing and pressure-volume loops. MRI investigations have been performed to monitor medical treatment, and the improvement in well-established prognostic factors, such as the 6-min walk, were correlated with measures of right ventricular function. Flow-derived parameters of the pulmonary arteries (such as peak velocity, acceleration time and volume, or pulmonary flow profile) are available using velocity-encoded imaging, and may detect early signs of remodelling. Additionally, magnetic resonance angiography is a promising new tool to visualise pulmonary perfusion and to diagnose chronic thromboembolic pulmonary hypertension. The purpose of this review is to summarise recent advances of cardiovascular magnetic resonance imaging, which will play an increasing role in the comprehensive diagnostic work-up of patients with pulmonary hypertension as a tool to monitor the course of the disease and to evaluate new therapeutic approaches., ((c) 2008 S. Karger AG, Basel.)

Objective: Orientation-related monoleaflet mechanical valve flow and velocity studies in the downstream are limited in mitral valve replacement studies., Methods: In five sheep, ventricular blood flow was visualized prior to the implantation of a Medtronic Hall tilting valve model. In six sheep, the implant orientation was either anatomical (disc aligned with the anterior leaflet) or anti-anatomical. The mitral subvalvular apparatus was preserved. Sheep were positioned within an 1.5 T field strength MR scanner (Magnetom Sonata; Siemens) to assess time-dependent three dimensional blood flow., Results: The preoperative ventricular velocity profiles presented negligible individual variances. Streamlines passed homogeneously without any spatial differences in flow velocities into the left ventricle. Starting from the anatomical position, blood entered mainly through the major orifice of the mechanical valve. The single artificial leaflet mimicked the rudder effect of the natural anterior mitral leaflet, preventing blood streaming directly towards the septum. The area with inhomogeneous blood velocities in the ventricle increased but not significantly from the preoperative status. The non-axial inflow not directed directly to the apex converted to a similar helix as observed in the preoperative cases. Anti-anatomical orientation of the prosthesis caused a significant increase in turbulence immediately after passing the mitral prosthesis. The main stream was changed so significantly that the blood flow shifted towards the septum and caused higher velocities of the stream profiles and turbulence apically., Conclusions: To achieve optimal hemodynamics, orientation of the mitral tilting valve has to be considered carefully, as has been long known from aortic valve replacement studies.

The clinical role of magnetic resonance in diseases of the heart and great vessels is rapidly evolving. Cardiovascular magnetic resonance (CMR) has become an established non-invasive imaging modality for the assessment of various cardiac disorders, such as congenital heart disease, cardiac masses, cardiomyopathies, aortic and pericardial diseases. Moreover, due to its accuracy and reproducibility, CMR is currently considered the gold standard for quantification of ventricular volumes, function, and mass. Thus, this technique is ideally suited to assess the efficacy of therapeutic interventions on ventricular hypertrophy and remodelling, which may allow a reduction in sample size to show clinically relevant effects. Comprehensive functional assessment is possible by CMR due to its capability to measure flow velocity and flow volume, which is a basic requirement to quantify lesion severity in valvular heart disease. Within the past years, major technical advances have considerably improved acquisition speed and image quality making CMR a useful tool for the evaluation of patients with ischaemic heart disease. Although the clinical robustness of coronary magnetic resonance angiography still needs improvement, CMR currently provides valuable information to detect reversible ischemia, myocardial infarction, and residual viability. In this review we will present in detail the well-established indications of CMR accompanied by an outlook on new applications that are likely to enter the clinical arena in the near future.

Objective: Methodological comparison of ellipsoid model-based approaches and Simpson method to evaluate left ventricular volumetric parameters by magnetic resonance (MR) and electron beam tomography (EBT) and analysis of the origin of possible discrepancies., Methods and Material: 100 subjects (87 patients, 13 healthy volunteers) were studied in MR in various cardiac views and EBT long axis view to determine left ventricular volumes and masses by applying (rotational) ellipsoid and Simpson model. Observer variation and method agreement was quantified by means of variance component and Bland-Altman analysis., Results: Simpson approach showed smaller observer variability than all ellipsoid approaches. All geometry-based models gave smaller left ventricular volumes than Simpson approach, the bias in mass determination was minimal. Whereas high correlation coefficients (typically 0.85-0.95) for left ventricular volume and mass measurements indicated satisfying correspondence between methods, large 95% limits of agreement made a transfer of results for single subjects between Simpson and ellipsoid approaches difficult and between different geometry-based models almost impossible. Because 95% limits of agreement and observer variability of geometry-based approaches were of equal order, the latter could be identified as main limiting factor of methodological agreement., Conclusion: MR Simpson approach is superior to all ellipsoid model-based approaches, because observer variability is smaller.

An easy applicable method for pre-operative port position planning for totally endoscopic coronary artery bypass (TECAB) grafting based on magnetic resonance (MR) coronary angiography and image post-processing is introduced and analyzed. For this, combined left main (LM) and left anterior descending (LAD) coronary arteries of 21 subjects (14 patients, 7 healthy volunteers with similar habitus) were investigated in MR by means of transversally orientated, three-dimensional (3D), fat-saturated, breath-hold true fast imaging with steady state precession sequences with real-time navigator-based slice following. For the healthy volunteers, the vertical dimension of the total 3D slab was enlarged to enable TECAB planning. Optimal endoscopic port positions were determined via image analysis and geometric methods. 13.8+/-2.1 cm mean continuously visible length of combined LM and LAD coronary arteries (no statistical difference between patients and healthy volunteers) allowed visualizing typical regions for suturing of the anastomosis in all 21 cases. The mean horizontal distance of the optimal endoscopic port position from the center of the sternum was 7.0+/-1.3 cm. In conclusion, MR imaging-based port position planning is feasible. Variability in the determined port positions indicates the necessity of adaptation of port positioning even for subjects with similar habitus.

The importance of the neurobiological basis of developmental language disorders includes somatosensory modalities. Twenty-five children were diagnosed as having specific language-impairment at preschool age. All were examined with regard to their manual haptic form discrimination without visual control at a mean age of 8.7 years +/- 7.1 months. This study group was compared to age- and gender-matched normal children of equal non-verbal intelligence (control group). Haptic discrimination was measured with the Seguin formboard on which the children were required to place ten geometrical forms in appropriate holes. Both groups differed significantly in their mean quantitative performances in favor of the control group (P < 0.05). The difference in their mean performance and their mean discrimination times did not reach statistical significance. All results were not age-dependent. The control group on average performed significantly better with their left hands than the study group (P < 0.05). Qualitative analysis revealed a significant difference in haptic discrimination of the pointed forms and was probably caused by inadequate exploration procedures and/or cognitive representation deficits. The results of the children with previous developmental language disorders were interpreted as an expression of an impaired cerebral maturation.

In coronal and paramediansagittal sections the intraorbital fatty tissue and compartments were examined. Discussed are the septa by the neurosurgical approach, the most important fastening apparatus of the eyeball and blow-out fractures.

The distances between the sclera of the bulb and the orbital walls and between the sclera and the external orbital muscles, the width of the orbital muscles and their distances to the orbital walls were measured. Values are given in millimeters (liminals). Discussed are the surgical approaches to the orbital contents.

The intracisternal, intrasinusoidal and intraorbital course of the sixth nerve is described, including the relative position in respect of the arachnoid membrane and the cerebral arteries. In addition, the relationships of the nerve in relation to possible injuries is considered.

The olfactory bulb has a length of 12.27 mm whereas the length of the olfactory tract from the beginning to where it crosses the optic nerve is 21.2 mm (mean). The intracranial portion of the optic nerve is 10.3 mm long. From the brain stem to its dural exit the III nerve measures 18.82 mm, and the IV nerve 32.65 mm. The range of variation in the lengths of the nerves, as well as their immediate relations are included in the investigation.

The course of the seventh to twelfth cranial nerves in the posterior fossa is described. The relation between the nerves and the cranial vessels, as well as their importance in practical medicine are discussed.

The course and lengths or the cranial nerves in the lateral wall of the cavernous sinus (Parkinson's triangle) and their relations to the internal carotid artery are described.

The mean length of the fifth nerve in the posterior fossa is 13.38 mm (medial portion) and 12.01 mm (lateral portion). Measurements of the triangular part of the trigeminal nerve, its branches and its central (vulnerable) part, are also described.