A rare case of an acute soleus arcade syndrome complicated by a ganglion cyst: diagnosis by dynamic ultrasound.

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.

A method for calcium quantification by means of CT coronary angiography using 64-multidetector CT: very high correlation with Agatston and volume scores.

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 (rho > 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.

Kidney fusion anomalies revisited: clinical and radiological analysis of 209 cases of crossed fused ectopia and horseshoe kidney.

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.

Phosphorus-31 two-dimensional chemical shift imaging in the myocardium of patients with late onset of Friedreich ataxia.

PURPOSE: 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. PROCEDURES: 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. RESULTS: The differences in left ventricular phosphocreatine (PCr) to beta-adenosine triphosphate (beta-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 beta-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. CONCLUSIONS: 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.

Dynamic T(1) mapping predicts outcome of chemoradiation therapy in primary rectal carcinoma: sequence implementation and data analysis.

PURPOSE: To describe details about the implementation of a dynamic T(1)-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 T(1) mapping was achieved with a snapshot fast low-angle shot (FLASH) T(1) mapping sequence implemented on a 1.5 T 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) T(1)-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 T(1) mapping has the potential to be a clinical tool for predicting therapy outcome of preoperative chemoradiation in patients with primary rectal carcinoma.

Anatomical considerations in TNM staging and therapeutical procedures for low rectal cancer.

BACKGROUND: 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. MATERIALS AND METHODS: 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. RESULTS: 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. CONCLUSION: 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.

Single-beat noninvasive imaging of cardiac electrophysiology of ventricular pre-excitation.

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.

Multimodality cranial image fusion using external markers applied via a vacuum mouthpiece and a case report.

PURPOSE: 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.