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Aims The present study was aimed to assess epi- and endocardial ventricular electroanatomical activation during cardiac resynchronization therapy (CRT) by means of non-invasive imaging of cardiac electrophysiology (NICE) in a patient with a novel quadripolar LV lead. Methods and results Non-invasive imaging of cardiac electrophysiology is a novel imaging tool which works by fusing data from high-resolution electrocardiogram (ECG) mapping with a model of the patient's individual cardiothoracic anatomy created from magnetic resonance imaging. This was performed in a cardiac resynchronization therapy defribrillator (CRT-D) patient with a quadripolar left ventricular (LV) lead. Beat-to-beat endocardial and epicardial ventricular activation sequences were computed using NICE during intrinsic conduction as well as during different pacing modes with different LV and biventricular (biV) pacing vectors. The spatial resolution of NICE enabled discrimination of the different pacing vectors during LV and biV pacing. Biventricular pacing resulted in a marked shortening of the total activation duration (TAD) of both ventricles when compared with intrinsic conduction and RV and LV pacing. Conclusion Non-invasive imaging of cardiac electrophysiology facilitates non-invasive imaging of ventricular activation, which may be useful in CRT patients to locate the area of latest ventricular activation as the target area for LV lead placement. Moreover, especially in non-responders to CRT NICE may be further useful to determine the best electrical repositioning option.

The aim of the present study was to monitor the microvascular perfusion damage in the acute and chronic stage after myocardial infarction (MI) using first-pass dynamic magnetic resonance imaging (MRI). Furthermore we compared improvement of myocardial microcirculation and function in infarcted and non-infarcted left midventricular segments over a 4 months period.Cardiac magnetic resonance imaging (CMR) was performed in 46 consecutive patients within 8 days after successful reperfused first acute ST-elevation MI and 4 months thereafter. First-pass images were obtained by using Turbo-FLASH sequence during a bolus injection of Gd-based contrast agent. Signal-intensity-to-time (SIT) curves of 276 left ventricular myocardial segments were generated. Furthermore, infarct volumes as well as parameters of regional left ventricular function of corresponding segments were calculated.SIT curves highly significantly correlate with MI size (r=-0.57, r=-0.43 respectively; all p0.0001) as well as with segmental wall thickening (SWT) of corresponding segments at baseline and follow-up scans (r=0.20, r=0.15 respectively; all p0.02). SWT differ highly significantly between segments with and those without LE at baseline (p0.003) and follow-up examinations (p0.008), presenting either clear improvements at follow-up (all p0.0001). In contrast, infarcted segments showing microvascular obstruction evidenced neither significant recovery of SIT nor of SWT (p=NS).Our data indicate a close relationship between MI size and myocardial perfusion as well as function. Beyond epicardial artery patency, the assessment of quantitative parameters of myocardial perfusion and contractile function with the help of CMR appears to be a useful tool for estimating myocardial recovery after acute MI.

The aim of the study was to find out if single time point and estimated cumulative release of cardiac troponin T (cTnT) and creatine kinase (CK) correlate with early infarct size and left ventricular function measured by cardiac magnetic resonance (CMR).CMR and serial CK and cTnT measurements were performed in 103 patients (85 male, mean age 55.8 ± 12.1 years) within at least 8 days (3.1 ± 1.5 days) after first acute myocardial infarction and successful primary percutaneous coronary interventions. Infarct size was determined on delayed gadolinium-enhanced phase-sensitive IR-SSFP CMR sequences. Single time point, peak and cumulative cardiac protein release were correlated with infarct size.All single time point, peak and estimated cumulative release of CK and cTnT values except on admission showed significant correlations with infarct size. Among single time point values, cTnT after 96 h (cTnT(96); r = 0.680, p0.001) and CK after 24 h (CK(24); r = 0.699, p0.001) showed the closest correlations with infarct size. Peak CK and cTnT levels correlated only slightly better than single time point values (r = 0.703 and 0.688, p0.001), whereas cumulative release values did not show closer correlations than single point values. Receiver-operator characteristics analysis showed that cTnT(96) and CK(24) detected large infarct areas (16.8 g) and decreased left ventricular function (EF40%) with high sensitivity and specificity.Both single time point cTnT concentrations and CK activities correlate well with infarct size early after primary PCI for STEMI. Cardiac TnT levels determined 3-4 days after revascularization for acute myocardial infarction allow for a good estimation of acute infarct size as well as an approximation of LV function and morphology.

To find out whether calcium scoring of the coronary arteries (CAC scoring) could be carried out with a CT angiography of the coronary arteries (CTCA) in a single CT data acquisition. The Agatston and V130 scores for 113 patients were assessed. A calcium volume score (V600 score) was compiled from the CTCA data sets. Intra- and interobserver correlations were excellent (ρ > 0.97). The intra- and interobserver repeatability coefficients were extremely low, increasing in magnitude from the V600 score to the V130 and Agatston scores. The V600 score underestimates the coronary calcium burden. However, it has a linear relation to the Agatston and V130 scores. Thus, they are predictable from the values of the V600 score. The V600 score shows a linear relation to the classic CAC scores. Due to its extremely high reliability, the score may be a feasible alternative for classic CAC scoring methods in order to reduce radiation dosages.

OBJECTIVE To analyse the morphological appearance of horseshoe kidneys (HKs) and crossed fused ectopia (CFE) and to assess the frequency and clinical significance of associated anomalies and diseases. PATIENTS AND METHODS The findings and images of 209 patients with fused kidneys (FKs) were reviewed; in all, 244 scans from computed tomography (CT), 233 ultrasonograms and 89 micturition cysto-urethrograms, urograms, magnetic resonance images and angiograms were taken. RESULTS HKs (found in one of 474 abdominal CT scans) and CFEs (found in one of 3078 CT scans) showed a high variability of vasculature that could not be classified. However, some generalized conclusions were possible about the renal vasculature (430 arteries in 103 kidneys). Variants of the most cephalad artery of both sides were rare. The second artery on the right had a pre-caval course. The origins of vessels located further caudal were more ventral. CFEs were anatomically different from HKs with respect to lower position, greater axial rotation, smaller pelvic width, more caudal origin, and fewer vessels, but not in accompanying anomalies. Severe anomalies or malformations were found in 23% of patients, with half of them in the urogenital system. Malformations were found considerably more often in children than in adults. There was no increased incidence of diseases such as stones or inflammation of the renal pelvis. CONCLUSION Concomitant anomalies and diseases were equally frequent for HK and CFE, but less frequent than generally assumed. Individual cases of complex anatomical situations require special examination strategies, and CT appears to be the most reliable imaging method.

This is a report of a case of a 26-year-old patient suffering from progressive renal insufficiency with a neurogenic bladder disorder due to a lipomyelomeningocele. She had renal agenesis on the left side and grade III hydronephrosis of both segments of a right duplex kidney with a bifid ureter joining further distal to the kidney. Both ureters were dilated. The cause was found to be a yo-yo reflux between the two halves of the kidney. Following bladder augmentation and pyelopyelostomy, renal insufficiency improved to stage III and has now been stable for four years. Due to the contralateral renal agenesis, the case is a unique illustration of the functional effect of the yo-yo reflux and pyelopyelostomy.

Separation of the mesoderm-derived muscular structures and the endoderm-derived structures of the hindgut and reclassification of their involvement based on their embryological origin may be of clinical importance in providing anatomical support for a more standardized perineal resection during abdominoperineal resection. The aim of this study was to utilize magnetic resonance images and histological studies of fetal and neonatal specimens to redefine the T3/T4 distinction by reassessment of the intersphincteric plane and the pelvic diaphragm as they pertain to cancer infiltration and as part of the embryological development of the pelvic floor muscles and their connective tissue compartments.Pelvic floor anatomy was studied in seven newborn children and 120 embryos and fetuses. Anatomical data were completed by magnetic resonance imaging in 82 patients with T3 and T4 rectal cancers (64 T3, 18 T4; 35 women and 47 men) undergoing neoadjuvant chemoradiation for locally advanced (T3 or T4) rectal cancers.Clear demarcation between mesodermal and endodermal structures of the pelvic floor, which is equally evident in plastinated sections and magnetic resonance images, is already visible in early fetal stages. There is a constitutive overlap between the endoderm- and the ectoderm-derived components of the pelvic floor.Our data suggest that the current classification of rectal cancer staging is confusing, where the routinely used TNM classification system unnecessarily differentiates between embryologically identical muscular structures. Tumor spread along the musculature of the hindgut beyond the dentate line could possibly explain the occasional involvement of lymph nodes outside the conventional mesorectum.

Apical ballooning is an increasingly reported transient cardiomyopathy with yet unknown origin. In this study 2 cases of apical ballooning are described in whom we used a combined approach of cardiac magnetic resonance imaging (CMR) and 31-Phosphorous magnetic resonance spectroscopy (31P MRS). Electrocardiogram showed ST abnormalities and cardiac serum markers were mildly elevated, but CAG demonstrated smooth coronary arteries. Cine-CMR revealed severe apical akinesia and significantly decreased ejection fraction. Furthermore we detected reduced myocardial phosphocreatine to beta-ATP (PCr/b-ATP) ratios during the first week of acute disease. After 1 week we observed an improvement of PCr/b-ATP ratios by 68% and 34%, which was associated with an increase in left ventricular function. Our data suggest that 31P MRS might be a valuable tool in the evaluation of apical ballooning, but larger cohorts are needed to improve the understanding of metabolic changes during transient apical ballooning.

We describe a unique case of bilateral os lunatotriquetrum associated with bilateral hypoplasia of the scaphoid bone. On both sides, the medial carpi were in a single row. The capitate bone occupied the lunate position, whereas the lunatotriquetral bone was displaced ulnarly and tilted. The capitate thus articulated with the radius and metacarpal bones, consistent with carpal collapse. In addition, there was congenital proximal radioulnar synostosis on the left side.

The present study assessed patterns of brain tissue alterations in different types of primary dystonia using voxel-based morphometry (VBM). Nine patients with primary generalized dystonia (GD), 11 patients with primary cervical dystonia (CD), and 11 patients with primary focal hand dystonia (FHD) as well as 31 age and gender-matched controls were included. When compared with healthy controls, patients with primary dystonia (n=31) showed gray matter volume increase bilaterally in the globus pallidus internus, nucleus accumbens, prefrontal cortex, as well as unilaterally in the left inferior parietal lobe. This is the first study using VBM in patients with different types of primary dystonia, showing a common pattern of gray matter changes.

The purpose of this study was to retrospectively assess the accuracy of gray-scale and color Doppler sonography in the diagnosis of carpal tunnel syndrome.A total of 206 wrists in 151 patients with a clinical suspicion of carpal tunnel syndrome were examined with high-resolution sonography using a 7-15-MHz linear array transducer. The presence of median nerve swelling, edema, and flattening and increased bowing of the flexor retinaculum was evaluated with gray-scale sonography, and the presence of nerve hypervascularization was evaluated with color Doppler sonography. Sensitivity and specificity were calculated for each sonographic feature in comparison with nerve conduction studies as the standard of reference. Multivariate logistic regression analysis was used to determine variables predictive of carpal tunnel syndrome.Carpal tunnel syndrome was confirmed in 172 wrists at nerve conduction studies. A median nerve cross-sectional area of at least 0.11 cm2 was calculated as a definition of median nerve swelling. In comparison with nerve conduction studies, nerve swelling showed the highest accuracy (91%) among gray-scale sonography criteria, and the presence of intraneural hypervascularization showed the highest accuracy (95%) among all sonography criteria. Logistic regression analysis showed that nerve hypervascularization was the only variable that independently predicted median nerve entrapment (odds ratio, 16.4; 95% confidence interval, 8.7-31.1; p0.001).Color Doppler sonography is more accurate than gray-scale sonography for characterizing median nerve involvement in patients with suspected carpal tunnel syndrome.

Background and purpose Voxel-based morphometry (VBM) is a magnetic resonance imaging (MRI)-based indirect volumetry, which allows the investigation of the entire brain without restriction of predefined regions-of-interest. Recent studies using this technique reported controversial results in patients with narcolepsy. Patients and methods In this study, 12 patients with narcolepsy according to the criteria of the International Classification of Sleep Disorders were compared to 12 age-matched controls with normal MR images using VBM. Sex and global differences in voxel intensities were used as confounding covariates. Results Significant gray matter loss was found in the right prefrontal and frontomesial cortex of patients with narcolepsy. White matter comparison revealed no significant changes in patients or controls. The comparison of cerebrospinal fluid partition detected an enlargement of subarachnoidal space of controls close to the prefrontal cortex. Conclusions The volume reduction of gray matter in narcoleptic patients could indicate a disease-related atrophy pattern. However, the results of VBM studies in narcolepsy are contradictory. A possible systematic bias due to inhomogeneous patient groups, stimulant medication history or pre-statistical image processing must be considered. We suggest that studies with drug-naive patients and/or region-of-interest-based volumetric studies should be performed in areas defined by VBM.

Takayasu arteritis (TA) is a chronic inflammatory vasculitis of the aorta and its major branches with a very low incidence in Europe and North America. Our objective was to determine the elastic properties of the affected ascending and descending aortic walls non-invasively in a 14-year-old Iraqi girl with a 3-year history of fever, fatigue, malaise and diffuse pain. Ultrasound and magnetic resonance angiography showed marked thickening of the aortic wall, dilatation of the aortic arch, and decreased luminal diameters of the abdominal aorta and both subclavian arteries, consistent with TA. Ascending and descending aortic elastic properties such as distensibility and stiffness index were markedly reduced compared to a group of healthy controls (n=39): ascending aortic distensibility was 20 kPa(-1) x 10(-3) versus 63+/-23 kPa(-1) x 10(-3) in controls, and the ascending aortic stiffness index 9.6 versus 3.5+/-1.3 in controls. Although the patient's general condition improved rapidly on oral prednisolone and azathioprine and inflammatory parameters normalised within 3 weeks, the aortic elastic parameters did not change during the first 2 weeks of anti-inflammatory treatment. Unfortunately, no further follow-up was possible.In patients with Takayasu arteritis, non-invasive quantification of reduced aortic elastic properties can help to assess aortic involvement, and possibly to follow disease activity and vascular response to therapy.

Analysis of shape began to emerge as a useful method in medical image computing with the potential to improve the accuracy of medical diagnosis as well as the understanding of processes behind growth and disease. Our work aims at investigating the suitability of the medial representation method (m-reps) to model and analyze shape and shape differences between healthy and diseased hearts. For this experimental study we used MRI short axis scans of 16 male subjects, 11 healthy volunteers (age: 50 ± 10) and 5 patients (age: 57 ± 11) with dilatative cardiomyopathy (CMP, EF: 22 ± 10%). Controlled semi-automated segmentation using the level set method provided labels, which were used for the modeling process. To evaluate the model to image quality the similarity index (SI) was calculated. The SI for the left ventricle was 0.93, and for the right ventricle SI = 0.9. Applying extended Principal Component Analysis (PCA) on all 16 subjects revealed the distribution of the individual shapes, showing discrimination between healthy and diseased ventricles. The first two main components of the PCA, mainly responsible for discrimination, cover more than 40% of the whole shape space. Applying the medial based approach and using shape statistics using component analysis for the left and right ventricle is feasible. This preliminary work promises to discriminate at least globally based on shape differences between healthy and diseased hearts. The resulting question however is, if this approach is good enough to detect early structural changes leading to diseased hearts.

Aim of the present functional magnet resonance imaging (fMRI) study was to detect modifications of cerebral activation patterns related to learning arithmetic. Thirteen right-handed subjects were extensively trained on a set of 18 complex multiplication problems. In the following fMRI session, trained and untrained problems (closely matched for difficulty) were presented in blocked order alternating with a number matching task and a fact retrieval task. Importantly, left hemispheric activations were dominant in the two contrasts between untrained and trained condition, suggesting that learning processes in arithmetic are predominantly supported by the left hemisphere. Contrasting untrained versus trained condition, the left intraparietal sulcus showed significant activations, as well as the inferior parietal lobule. A further significant activation was found in the left inferior frontal gyrus. This activation may be accounted for by higher working memory demands in the untrained as compared to the trained condition. Contrasting trained versus untrained condition a significant focus of activation was found in the left angular gyrus. Following the triple-code model [Science 284 (1999) 970], the shift of activation within the parietal lobe from the intraparietal sulcus to the left angular gyrus suggests a modification from quantity-based processing to more automatic retrieval. The present study shows that the left angular gyrus is not only involved in arithmetic tasks requiring simple fact retrieval, but may show significant activations as a result of relatively short training of complex calculation.

To present a simple and precise method of combining functional information of cranial SPECT and PET images with CT and MRI, in any combination. Material and Methods: Imaging is performed with a hockey mask-like reference frame with image modality-specific markers in precisely defined positions. This frame is reproducibly connected to the VBH vacuum mouthpiece, granting objectively identical repositioning of the frame with respect to the cranium. Using these markers, the desired 3-D imaging modalities can then be manually or automatically registered. This information can be used for diagnosis, treatment planning, and evaluation of follow-up, while the same vacuum mouthpiece allows precisely reproducible stereotactic head fixation during radiotherapy. Results: 244 CT and MR data sets of 49 patients were registered to a root square mean error (RSME) of 0.9 mm (mean). 64 SPECT-CT fusions on 18 of these patients gave an RMSE of 1.4 mm, and 40 PET-CT data sets of eight patients were registered to 1.3 mm. An example of the method is given by means of a case report of a 52-year-old patient with bilateral optic nerve meningioma. Conclusion: This technique is a simple, objective and accurate registration tool to combine diagnosis, treatment planning, treatment, and follow-up, all via an individualized vacuum mouthpiece. Especially for low-resolution PET and even more so for some very diffuse SPECT data sets, activity can now be accurately correlated to anatomic structures.

The soleus arcade syndrome is a rare compression neuropathy of the tibial nerve that often remains undiagnosed due to low clinical awareness and difficult diagnosis. We present the case of a female patient admitted with acute worsening of a pre-existing sensory tibial neuropathy and acute tibial nerve palsy after knee joint injection. After a knee magnetic resonance imaging remained non-diagnostic, dynamic ultrasonography was performed. Constriction by the soleus arcade and proximal swelling of the tibial nerve could be demonstrated during plantarflexion of the ankle by means of a dynamic examination in the standing patient. The patient underwent surgery and recovered fully. This proposed diagnostic approach can be used to identify soleus arcade syndrome by ultrasound.

Propionic acidemia is an inherited disorder caused by a defect of propionyl CoA carboxylase. Untreated, propionic acidemia leads to metabolic decompensation and toxic encephalopathy. We report on the magnetic resonance imaging (MRI) and magnetic resonance spectroscopy (MRS) findings in five children who were properly treated by protein restriction and carnitine supplementation, during a phase of clinically and metabolically stable conditions. The examinations were performed on a whole-body 1.5 T scanner. During the observation period, from 1992 to 1996 we employed long echo time single-voxel spectroscopy and chemical shift imaging in addition to a conventional MRI protocol. The two children with the longest delay before onset of therapy showed cerebral atrophy. MRS yielded elevated lactate peaks in four of the children. These results indicate that MRS can detect metabolic alterations in the brains of children with propionic acidemia during metabolically stable conditions. The presence of lactate could be caused by hampered aerobic oxidation within the citrate cycle due to intracellular elevated propionic metabolites.

A 39-year-old man presented with erectile dysfunction that had persisted since its sudden onset 5 years ago. He exhibited none of the classic risk factors, and all attempts at medication had been unsuccessful. An ultrasound examination revealed the presence of an arteriovenous shunt in the corpus spongiosum penis. Selective digital subtraction angiography of the left internal pudendal artery showed an arteriovenous fistula from the arteria bulbi penis to the corpus spongiosum penis. The outflow of venous blood took place via the penile veins into the periprostatic vein plexus. Superselective catheterization of the arteria bulbi penis was performed with a 3 French coaxial catheter (Topaz Micro Coils; Micro Therapeutics, Inc, Irvine, CA) and it was occluded by inserting several platinum coils. 1 week after the procedure, the patient reported normal erectile function, which was subsequently maintained.

Objective To find and evaluate characteristic magnetic resonance imaging (MRI) patterns for the differentiation between Ewing sarcoma and osteomyelitis. Materials and methods We identified 28 consecutive patients referred to our department for MRI (1.5 T) of an unclear bone lesion with clinical symptoms suggestive of Ewing sarcoma or osteomyelitis. MRI scans were reevaluated by two experienced radiologists, typical MR imaging features were documented and a diagnostic decision between Ewing sarcoma and osteomyelitis was made. Statistical significance of the association between MRI features and the biopsy-based diagnosis was assessed using Fisher’s exact test. Results The most clear-cut pattern for determining the correct diagnosis was the presence of a sharp and defined margin of the bone lesion, which was found in all patients with Ewing sarcoma, but in none of the patients with osteomyelitis (P

Purpose: To assess the relation of cardiac troponin T (cTnT) and creatine kinase (CK) release with infarct size and left ventricular function evaluated during the subacute phase as well as four months after acute myocardial infarction (AMI) by contrast-enhanced MRI (CE-MRI). Materials and Methods: CMR of 80 patients (68 male, mean age 54.2 ± 11.7 years) was performed within 8 days and 4 months after first acute ST-elevation AMI with successful primary angioplasty. CK and cTnT concentrations were determined serially from admission to day 4 after symptom onset. Results: All single time-points, estimated average release and peak concentrations of CK and cTnT markers correlated significantly with acute and mid-term infarct size (r = 0.43 to 0.79, all P < 0.001), ejection fraction (EF%) (r = −0.42 to −0.58, all P < 0.002) as well as with end-systolic volume (ESV) (r = 0.32 to 0.57, all P < 0.002) at all times of assessment. Patients with cTnT concentrations below the cutoff value of 3.26 μg/L measured 48 h after AMI-related symptom onset had a significant improvement in global (EF: P < 0.0001) myocardial function during the study period, whereas in those with cTnT ≥ 3.26 μg/L, functional recovery did not occur (P = 0.09). Conclusion: All single, mean and maximum concentrations of cTnT and CK measured within the first 4 days after AMI permit an accurate prediction of infarct size and left ventricular function as determined in the acute phase as well as four months after AMI by CE-MRI. J. Magn. Reson. Imaging 2011;33:847–854. © 2011 Wiley-Liss, Inc.

We sought to assess the relation of late microvascular obstruction (l-MVO) size as quantified by cardiac magnetic resonance (CMR) imaging with cardiac and inflammatory marker concentrations after acute myocardial infarction (AMI).CMR was performed in 118 consecutive patients within 8 days after successful interventional reperfused first acute ST-elevation AMI. Infarct volumes and l-MVO sizes were calculated from late enhancement (LE) sequences and functional parameters were determined from short-axis cine MR sequences. Creatine kinase (CK) and cardiac troponin T (cTnT), high-sensitivity C-reactive protein (hs-CRP) as well as lactate dehydrogenase (LD) concentrations were determined serially from day 1 to day 4 after symptom onset.L-MVO was detected in 66/118 patients (55.9%) and comprised 18.2 ± 10% of infarct size and 4.7 ± 3% of left ventricle myocardial mass. Each single-point, peak and cumulative release concentration of cTnT (r=0.44 to 0.73, p0.0001), CK (r=0.21 to 0.76, p0.0001), LD (r=0.36 to 0.82, all p0.0001) as well as hs-CRP single-point values as assessed from day 1 to day 4 and its peak and cumulative release concentrations (r=0.24 to 0.49, p0.003) significantly correlated with l-MVO size. Receiver operating curve (ROC) analysis indicated a cut-off value of 4.7 μg/l cTnT to best identify the presence of l-MVO (area under the curve (AUC) 0.904; 95% CI: 0.85-0.95; p0.0001).L-MVO sizes significantly correlate with cardiac and inflammatory marker concentrations as determined early after AMI. cTnT concentration of4.7 μg/l could help to identify patients in whom l-MVO is present.

To assess with cardiac magnetic resonance imaging (CMR) the relationship between treatment delay and improvement of regional left ventricular function after primary percutaneous transluminal coronary angioplasty (p-PTCA) for acute myocardial infarction (AMI).We performed cine- and late-enhancement (LE) CMR in 40 patients with first AMI after restoring TIMI 3 flow with p-PTCA and at a follow-up 4 months later. Infarcted segments were determined from LE images. Regional left ventricular function was quantified from cine-CMR images. Segmentation followed the American Heart Association 17-segments model. Patients were divided into groups with delay3 hours, 3-6 hours, 6-12 hours, and a delay12 hours.Segmental wall thickening (SWT) significantly iproved only in segments reperfused within 6 hours (P0.001). Follow-up SWT was significantly higher if segments were reperfused early (3 hours: 74 +/- 4%, 3-6 hours: 57 +/- 4%, 6-12 hours: 48 +/- 7%,3 to 3-6: P0.003, and3 to 6-12 hours: P0.001). The extent of improvement was greater if delay was3 hours compared to segments with a delay of3 hours (3 hours: +21 +/- 3%, 3-6 hours: +8 +/- 4%, 6-12 hours: +6 +/- 3%;3 hours to 3-6 hours, and 6-12 h, P0.02).We quantitatively demonstrated that time to p-PTCA treatment significantly influences regional functional recovery of infarcted myocardium at a 4-month follow-up.

Background We report on a case of an impar umbilical artery (IUA) in an 18-year-old woman. Case presentation The aorta branched off at level L2 into a ventral IUA and a dorsal aorta. The strong IUA produced the inferior mesenteric artery (IMA), the renal artery of a left-sided duplex kidney, and the right-sided ovarian artery before it turned to the right to merge into the right common iliac artery. From the aorta arose the lumbar arteries, the median sacral artery, lateral sacral arteries, and iliolumbar arteries before it turned to the left. Both vessels were connected by an artery 0.8 cm in diameter running infraperitoneal, from the left side of which the uterine artery arose for a left paramedian uterus didelphys. Conclusion This anatomical situation is presented for the first time using an arterial contrast enhanced CT and is discussed within the context of previously known cases.

In this paper we present a new approach for the registration of cardiac 4D image sequences of different subjects, where we assume that a temporal association between the sequences is given. Moreover, we allow for one (or two) selected pair(s) of associated points in time of both sequences, which we call the bridging points in time, the use of additional information such as the semi-automatic segmentation of the investigated structure. We establish the 3D inter-subject registration for all other pairs of points in time exploiting (1) the inter-subject registration for the bridging pair of points in time, (2) the intra-subject motion calculation in both sequences with respect to the bridging pair, and (3) the concatenation of the obtained transformations. We formulate a cost functional integrating the similarity measures comparing the images of the bridging pair(s) of points in time and of the current pair of points in time, respectively. We evaluated our algorithm on 8 healthy volunteers leading to 28 inter-subject combinations and we analyze the behaviour for different parameter settings weighting differently the involved pairs of points in time. The approach based on the bridging pairs outperforms a direct 3D registration of corresponding points in time, in particular in the right ventricle we gain up to 33% in registration accuracy. Starting with a cost functional taking into account the similarity at the first bridging point in time, the results improve stepwise by integrating, firstly, information from the current pair of points in time and secondly, from a second bridging point in time. Our results also show a steep rise of the importance of regularization on the registration accuracy when registering the current point in time with our procedure (17% gain in accuracy) with respect to a direct registration in the bridging point (less than 1%). However, regularization during intra-sequence registration had only minor effects on the accuracy of our registration procedure.

Purpose To describe details about the implementation of a dynamic T1-mapping technique and a simple data analysis strategy that can be used to predict therapy outcome in primary rectal carcinoma and to investigate the physiologic meaning of the obtained parameter. Materials and Methods Contrast-enhanced dynamic T1 mapping was achieved with a snapshot fast low-angle shot (FLASH) T1 mapping sequence implemented on a 1.5T MR scanner. This method was applied to 58 patients with primary rectal cancer before onset of chemoradiation therapy. A simple data analysis strategy based on the calculation of the maximum slope of the tissue concentration–time curve divided by the maximum of the arterial input function (AIF) was used as a measure of tumor microcirculation (PI values). Results The snapshot FLASH (SFL) T1-mapping technique is accurate and sensitive enough to detect inhomogeneous uptake kinetics within tumor tissue. Classifying the patients into two groups according to therapy response showed lower mean PI values for responders as compared to nonresponders. PI was found to combine information about permeability surface area product (PS) and blood volume. Conclusions The described method based on dynamic T1 mapping has the potential to be a clinical tool for predicting therapy outcome of preoperative chemoradiation in patients with primary rectal carcinoma. J. Magn. Reson. Imaging 2007;26:662–671. © 2007 Wiley-Liss, Inc.

Friedreich ataxia (FRDA) is characterized by GAA expansions in the intron 1 of the frataxin gene correlating with disease onset and progression as well as cardiac affection. Accordingly, FRDA patients with early disease onset show a clear impairment of mitochondrial function in the myocardium. The purpose of this study was to investigate cardiac function and high-energy phosphate metabolism in FRDA patients with late disease onset. Using a 1.5 T magnetic resonance scanner, cardiac phosphorus-31 two-dimensional chemical shift imaging was performed in ten patients (seven male, three female) with a late onset of FRDA and in 35 healthy, male controls. Ejection faction (EF) and interventricular septum thickness (IST) were determined by echocardiography. The differences in left ventricular phosphocreatine (PCr) to β-adenosine triphosphate (β-ATP) ratios between both groups were not significant. FRDA patients had increased ISTs (10.8 ± 1.6 vs. 9.7 ± 0.9 mm; p = 0.048), which correlated significantly with the left ventricular PCr to β-ATP ratios (r = −0.644; p = 0.04), and decreased EFs (52.24 ± 7.72% vs. 64.09 ± 4.25%; p = 0.001) compared to normal controls. In contrast to FRDA patients with early disease onset, our patients collective exhibited a normal, probably compensated cardiac mitochondrial function, whereby IST and EF were mildly altered.

Purpose: The purpose of this study was to evaluate inter- and intra-rater reproducibility in volume assessment using cardiac magnetic resonance imaging (CMRI). Methods: Twenty-five healthy volunteers and 106 patients were included into this retrospective study and received CMRI. The patients were divided in three groups (group I, 80 patients with arrhythmia; group II, 20 patients with cardiomyopathy; group III, 6 patients after correction of septum defects). Therefore, the images were semiautomatically segmented by an experienced and an unexperienced radiologists. The analysis of end-diastolic volume (EDV), end-systolic volume (ESV) and stroke volume (SV) as well as ejection fraction (EF) and myocardial mass (MM) were performed twice by an experienced and an unexperienced radiologists. The intra-class correlation coefficients (ICC) were determined for the evaluation of inter- and intra-rater variance. Results: The intra-rater reproducibility for determination of EF, ESV, EDV and MM was excellent with ICCs ranging from 0.88 to 0.99 (all p < 0.001). The inter-observer reproducibility for these parameters was also excellent with ICCs ranging from 0.91 to 0.98 (all p < 0.001). The assessment of the SV showed an excellent intra-rater agreement with ICCs of 0.96 and 0.92 (both p < 0.001), but only a moderate ICC for the inter-rater reproducibility (0.54, p < 0.001). Conclusions: Our study shows that assessment of cardiac volumes can be performed on CMRIs with an excellent reproducibility by both experienced and unexperienced investigators. © 2007 Elsevier Ireland Ltd. All rights reserved.

Summary: Purpose: Recent studies have claimed that language functional magnetic resonance imaging (f MRI) can identify language lateralization in patients with temporal lobe epilepsy (TLE) and that f MRI-based findings are highly concordant with the conventional assessment procedure of speech dominance, the intracarotid amobarbital test (IAT). Methods: To establish the power of language f MRI to detect language lateralization during presurgical assessment, we compared the findings of a semantic decision paradigm with the results of a standard IAT in 68 patients with chronic intractable right and left temporal lobe epilepsy (rTLE, n = 28; lTLE, n = 40) who consecutively underwent a presurgical evaluation program. The patient group also included 14 (20.6%) subjects with atypical (bilateral or right hemisphere) speech. Four raters used a visual analysis procedure to determine the laterality of speech-related activation individually for each patient. Results: Overall congruence between f MRI-based laterality and the laterality quotient of the IAT was 89.3% in rTLE and 72.5% in lTLE patients. Concordance was best in rTLE patients with left speech. In lTLE patients, language f MRI identified atypical, right hemisphere speech dominance in every case, but missed left hemisphere speech dominance in 17.2%. Frontal activations had higher concordance with the IAT than did activations in temporoparietal or combined regions of interest (ROIs). Because of methodologic problems, recognition of bilateral speech was difficult. Conclusions: These data provide evidence that language f MRI as used in the present study has limited correlation with the IAT, especially in patients with lTLE and with mixed speech dominance. Further refinements regarding the paradigms and analysis procedures will be needed to improve the contribution of language f MRI for presurgical assessment. Key Words: Language f MRI—Temporal lobe epilepsy—Language lateralization—Intracarotid amobarbital test.

Functional imaging data suggest that the core network engaged in verbal semantic memory (SM) processing encompasses frontal and temporal lobe structures, with a strong left lateralization in normal right handers. The impact of long term temporal lobe epilepsy (TLE) on this network has only partly been elucidated. We studied verbal SM in 50 patients with chronic, intractable TLE (left TLE=26, right TLE=24) and 35 right handed normal controls using a verbal fMRI semantic decision paradigm. All patients had language lateralized to the left hemisphere, as verified by the intracarotid amobarbital procedure. Within and between group analyses showed remarkable, group-specific activation profiles. The control group activated frontal and temporal areas bilaterally, with a strong left predominance. Left TLE patients showed a shift of activations of left frontal and medial temporal areas to homologous regions in the right hemisphere. Furthermore, left TLE subjects utilized subcortical structures such as the thalamus and putamen to accomplish the verbal SM task. Contrastively, the activation pattern of right TLE patients resembled that of normal controls, but exhibited "hypofrontality" with a shift from frontal to posterior regions in the temporal, parietal and occipital lobe. Our results show that chronic epileptic activity originating from temporal seizure foci is associated with an alteration of neural circuits which support semantic language processing and that side of seizure focus has a specific impact on the resulting activation network. These findings presumably result from morphological changes and from functional reorganization which are both inherent to chronic TLE.

Objectives The aim of this study was to determine whether noninvasive imaging of cardiac electrophysiology (NICE) is feasible in patients with Wolff-Parkinson-White (WPW) syndrome in the clinical setting of a catheter laboratory and to test the accuracy of the noninvasively obtained ventricular activation sequences as compared with that of standard invasive electroanatomic mapping. Background NICE of ventricular activation could serve as a useful tool in the treatment of cardiac arrhythmias and might help improve our understanding of arrhythmia mechanisms. Methods NICE works by fusing the data from high-resolution electrocardiographic mapping and a model of the patient’s cardiac anatomy obtained by magnetic resonance imaging. The ventricular activation sequence was computed with a bidomain theory-based heart model to solve this inverse problem. Noninvasive imaging of cardiac electrophysiology was performed in 7 patients with WPW syndrome undergoing catheter ablation of the accessory pathway. The position error of NICE was defined as the distance between the site of earliest activation computed by NICE and the successful ablation site identified by electroanatomic mapping (CARTO; Biosense Webster, Diamond Bar, California) for normal atrioventricular (AV) conduction as well as for adenosine-induced AV block. Results The error introduced by geometric coupling of the CARTO data and the NICE model was 5 ± 3 mm (model discretization 10 mm). All ventricular accessory pathway insertion sites were identified with an accuracy of 18.7 ± 5.8 mm (baseline) and 18.7 ± 6.4 mm (adenosine). Conclusions The individual cardiac anatomy model obtained for each patient enables accurate noninvasive electrocardiographic imaging of ventricular pre-excitation in patients with WPW syndrome. Noninvasive imaging of cardiac electrophysiology might be used as a complementary noninvasive approach to localize the origin and help identify and understand the underlying mechanisms of cardiac arrhythmias.

We present an approach for fast reconstructing of cardiac myocardium and blood masses of a patient's heart from morphological image data, acquired either MRI or CT, in order to estimate numerically the spread of electrical excitation in the patient's atria and ventricles. The approach can be divided into two main steps. During the first step the ventricular and atrial blood masses are extracted employing Active Appearance Models (AAM). The left and right ventricular blood masses are segmented automatically after providing the positions of the apex cordis and the base of the heart. Because of the complex geometry of the atria the segmentation process of the atrial blood masses requires more information as the ventricular blood mass segmentation process of the ventricles. We divided, for this reason, the left and right atrium into three divisions of appearance. This proved sufficient for the 2D AAM model to extract the target blood masses. The base of the heart, the left upper and left lower pulmonary vein from its first up to its last appearance in the image stack, and the right upper and lower pulmonary vein have to be marked. After separating the volume data into these divisions the 2D AAM search procedure extracts the blood masses which are the main input for the second and last step in the myocardium extraction pipeline. This step uses morphologically-based operations in order to extract the ventricular and atrial myocardium either directly by detecting the myocardium in the volume block or by reconstructing the myocardium using mean model information, in case the algorithm fails to detect the myocardium.

For a clinical application of the inverse problem of electrocardiography, a flexible and fast generation of a patient's volume conductor model is essential. The volume conductor model includes compartments like chest, lungs, ventricles, atria and the associated blood masses. It is a challenging task to create an automatic or semi-automatic segmentation procedure for each compartment. For the extraction of the lungs, as one example, a region growing algorithm can be used, to extract the blood masses of the ventricles Active Appearance Models may succeed, and to construct the atrial myocardium a multiplicity of operations are necessary. These examples illustrate that there is no common method that will succeed for all compartments like a least common denominator. Another problem is the automatization of combining different methods and the origination of a segmentation pipeline in order to extract a compartment and, accordingly, the desired model - in our case the complete volume conductor model for estimating the spread of electrical excitation in the patient's heart. On account of this, we developed a C++ framework and a special application with the goal of creating tissue-specific segmentation pipelines. The C++ framework uses different standard frameworks like DCMTK for handling medical images (http://dicom.offis.de/dcmtk.php.en), ITK (http://www.itk.org/) for some segmentation methods, and Qt (http://www.trolltech.com/) for creating user interfaces. Our Medical Segmentation Toolkit (MST) enables to combine different segmentation techniques for each compartment. In addition, the framework enables to create user-defined compartment pipelines.

A geometrical model of the human heart is of interest in many fields of biophysics. The myocardium contains the electrical sources responsible for the generation of the body-surface ECG. An accurate geometric knowledge of these sources is crucial when dealing with the electrocardiographic forward and inverse problem. We developed a semiautomatic approach for segmenting the myocardium in order to deal with the electrocardiographic problem. The approach can be divided into two main steps. The first step extracts the atrial and ventricular blood masses by employing Active Appearance Models (AAM). The ventricular blood masses are segmented automatically after providing the positions of the apex cordis and the base of the heart. Due to the complex geometry of the atria the segmentation process of the atrial blood masses requires more information. We divided, therefore, the left and the right atrium into three divisions of appearance: the base of the heart, the lower pulmonary veins from its first up to the last appearance in the image stack, and the upper pulmonary veins. After successful extraction of the blood masses the second step involves morphologically-based operations in order to extract the myocardium either directly by detecting the myocardium in the volume block, or by reconstructing the myocardium using mean model information, in case the algorithm fails to detect the myocardium.

We determined brain atrophy patterns in dementia with Lewy bodies and Alzheimer's disease using voxel-based morphometry, an indirect volumetry. Ten patients with dementia with Lewy bodies, 10 patients with Alzheimer's disease and 10 controls were included. All groups were matched for age; sex and global differences in voxel intensities were included as confounding covariates. We observed basal forebrain atrophy discriminating dementia with Lewy bodies from Alzheimer's disease. Compared to controls, atrophy of lateral prefrontal cortex and left premotor cortex was seen in dementia with Lewy bodies whereas atrophy of the medial temporal cortex, posterior parietal cortex, thalamus and temporo-occipital areas was observed in Alzheimer's disease. Atrophy of insular cortex was found in both patient groups.

Medial temporal lobe (MTL) areas are well known to serve episodic memory functions; their contribution to semantic memory has been occasionally noticed but not studied in detail. In the present fMRI study, 35 right-handed and 35 left-handed healthy subjects performed a semantic decision paradigm during which subjects heard spoken concrete nouns designating objects and had to decide on whether these objects were available in the supermarket and cost lest then a certain amount of money. The control paradigm consisted of sequences of low and high tones where subjects had to decide whether a sequence contained two high tones. The resulting contrast activation of semantic decision versus tone decision involved neocortical temporal, parietal, and prefrontal areas. Additional significant, bilateral activations in the MTL, the hippocampal formation, and adjacent areas were found. The exact incidence and location of activation was studied in a single-subject analysis for all 70 subjects. At the chosen threshold of P