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A megacava (vena cava with a diameter of 28 mm or greater) requires a particular filter to avoid migration. However, caval morphologies are variable. As the inferior vena cava (IVC) usually adopts a circular geometry after a filter is inserted, this study aims (a) to classify caval geometry and orientation; (b) to compare discrepancy between anterioposterior projective diameter (PD) and circumference-based calculated diameter (CD) measurements on cross-sectional computed tomography (CT) images; (c) if a discrepancy exists, determine how often it can affect IVC filter selection. A total of 1503 patients were retrospectively reviewed. Caval morphology was classified. PD and CD were measured at infrarenal IVC. Differences between the PD and CD were assessed by the Wilcoxon signed-rank test or paired t test (if appropriate). The scatterplot of PD vs. CD was used to show whether one is consistently larger than the other. The PD was significantly larger than the CD (22.3 ± 3.5 vs. 20.4 ± 2.8, p

Introduction Atrial tachyarrhythmia is regarded as a late consequence of the Fontan circulation, particularly in those with an AP Fontan and is associated with significant morbidity and mortality. Developing methods to recognise those at the highest risk will allow early intervention, improving patient outcomes. Purpose To establish relationship between AP Fontan chamber (FC) dimensions, ventricular volumes and function and the development of atrial arrhythmia (AR). Methods Modified AP Fontan patients with CMR (1.5T, Avanto, Siemens) were reviewed (Figure 1). Horizontal long axis (HLA, TrueFISP cine, flip angle 80, TR/TE 50/1.26ms, retrospective ECG gating) and transaxial 3D MRA non-contrast (Modified Siemens Whole Heart coronary artery sequence, respiratory navigator, ECG-triggered, free breathing, slice thickness 2.00mm) of the FC and the left atrium were examined. Results 55 patients 58% female and 42% male, mean age 33yrs (SD 7.9). 32 patients suffered a documented AR, most commonly atrial flutter (79%). There was a significant difference in age between the two groups with those having an AR tending to be older (36yrs vs 29yrs p 0.05). There were no significant differences in atrial parameters between the two groups (p > 0.05), however all measures of the FC were statistically different with larger measures occurring in the AR group (p Conclusions Increasing AP FC size is associated with increased risk of AR.

Background Displacement encoding with stimulated echoes (DENSE) encodes myocardial tissue displacement into the phase of the MRI image permitting direct quantification of myocardial displacement at multiple cardiac phases. Strain-encoded CMR with DENSE has high spatial (3.2 mm × 3.2 mm × 8 mm) and temporal resolution (TR= 27.34 ms). We aimed to measure myocardial strain values with DENSE in healthy adults across a broad age range at 3.0Tesla. Methods Healthy volunteers with no prior medical history or treatment were enrolled and underwent CMR at 3.0T (Magnetom Verio, Siemens, Erlangen, Germany). Mid-left ventricular short axis and horizontal long axis DENSE sequences were obtained, and analysed using CIM_DENSE2D software (University of Auckland, New Zealand and Siemens Healthcare). Segmental and global myocardial circumferential (Ecc) and longitudinal (Ell) strain were obtained with DENSE. Results 77 participants (mean (SD) age 43.0(16.9) years; range 18–78 years; 40 (52%) males;) were grouped into 3 tertiles according to age. Longitudinal strain differed according to age tertile with strain being greatest in individuals 35–55 years compared to younger or older subjects. There were no differences in Ecc according to age per tertile (Table 1). Conclusion Longitudinal myocardial strain, as revealed by strain-encoded CMR, is associated with chronological age in healthy adults. Funding Medical Research Scotland project grant. Professor Berry was supported by a Senior Clinical Fellowship from the Scottish Funding Council.

We sought to determine which of the three orientations is the most reliable and accurate for quantifying right ventricular (RV) volume and ejection fraction (EF) by cardiac magnetic resonance using Simpson’s method. We studied 20 patients using short axis (SA), transaxial (TA), and horizontal long axis (HLA) orientations. Three readers independently traced RV endocardial contours at end-diastole and end-systole for each orientation. End-diastolic volumes (EDVs), end-systolic volumes (ESVs), and EF were calculated and compared with the 3D piecewise smooth subdivision surface (PSSS) method. The intraclass correlation coefficients among the 3 readers for EDV, ESV, and EF were 0.92, 0.82, and 0.42, respectively, for SA, 0.95, 0.92, and 0.67 for TA, and 0.85, 0.93, and 0.69 for HLA. For mean data there was no significant difference between TA and PSSS for EDV (−2.6%, 95% CI: −8.2 to 3.3%), ESV (−5.9%, −15.2 to 4.5%), and EF (1.7%, −1.5 to 4.9%). HLA was accurate for ESV (−8.9%, −18.5 to 1.8%) and EF (−0.7%, −3.8 to 2.5%) but significantly underestimated EDV (−9.8, −16.6 to −2.4%). SA was accurate for EDV (0.5%, −6.0 to 7.5%) but overestimated ESV (10.5%, 0.1 to 21.9%) and had poor interrater reliability for EF. Conclusions. The TA orientation provides the most reliable and accurate measures of EDV, ESV, and EF.

Purpose: The purpose of this study was to evaluate a horizontal long axis (HLA) magnetic resonance imaging (MRI) plane aligned to the long axis of the right ventricular (RV) cavity for functional analysis by comparing the measurement variability and time required for the analysis with that using a short-axis (SAX) image orientation. Materials and Methods: Thirty-four cardiac MRI exams with cine balanced steady-state free precession image stacks in both the SAX and the HLA of the RV (RHLA) were evaluated. Two reviewers independently traced RV endocardial borders on each image of the cine stacks. The time required to complete each set of traces was recorded, and the RV end-diastolic volume, end-systolic volume, and ejection fraction were calculated. Analysis times and RV measurements were compared between the two orientations. Results: Analysis time for each reviewer was significantly shorter for the RHLA stack (reviewer 1 = 6.4 ± 1.8 min, reviewer 2 = 6.0 ± 3.3 min) than for the SAX stack (7.5 ± 2.1 and 6.9 ± 3.6 min, respectively; P < 0.002). Bland–Altman analysis revealed lower mean differences, limits of agreement, and coefficients of variation for RV measurements obtained with the RHLA stack. Conclusions: RV functional analysis using a RHLA stack resulted in shorter analysis times and lower measurement variability than for a SAX stack orientation.

To determine the accuracy of visual analysis of left ventricular (LV) function in comparison with the accepted quantitative gold standard method, Cardiac Magnetic Resonance (CMR). Cine CMR imaging was performed at 1.5 T on 44 patients with a range of ejection fractions (EF, 5-80%). Clinicians (n = 18) were asked to visually assess EF after sequentially being shown cine images of a four chamber (horizontal long axis; HLA), two chamber (vertical long axis; VLA) and a short axis stack (SAS) and results were compared to a commercially available analysis package. There were strong correlations between visual and quantitative assessment. However, the EF was underestimated in all categories (by 8.4% for HLA, 8.4% for HLA + VLA and 7.9% for HLA + VLA + SAS, P all < 0.01) and particularly underestimated in mild LV impairment (17.4%, P < 0.01), less so for moderate (4.9%) and not for severe impairment (1%). Assessing more than one view of the heart improved visual assessment of LV, EF, however, clinicians underestimated EF by 8.4% on average, with particular inaccuracy in those with mild dysfunction. Given the important clinical information provided by LV assessment, quantitative analysis is recommended for accurate assessment. © 2010 Springer Science+Business Media, B.V.

Methods Cine cardiac MR imaging was performed on 44 subjects with a range of ejection fractions on a 1.5 T Siemens clinical scanner. Clinicians (N = 18) with varying degrees of cardiac MR experience (0 to 13 years) were shown cine images of a four chamber (horizontal long axis; HLA), two chamber (vertical long axis; VLA) and a stack of short axis stack (SAS) images. They were asked to visually assess the ejection fraction (EF) after seeing 10 cardiac cycles of a HLA alone, then HLA + VLA, then the HLA + VLA +SAS. These results were compared to a commercial available LV analysis package (Argus processing).

Radiologic Description An oblique axial T2-weighted MR image (Fig. 1) through the horizontal long axis of the uterus shows a muscular septum arising from the fundus and extending into the body region; the overlying junctional zone is continuous over the lateral walls of the uterus. The outer contour of the fundus is flattened, whereas a normal uterine fundus is convex on the outer aspect. The left ovary seen in this image is unremarkable. The right ovary, seen better on a different image (not shown), is also normal in appearance.

Background Displacement encoding with stimulated echoes (DENSE) encodes myocardial tissue displacement into the phase of the MRI image, thus allowing direct quantification of myocardial displacement at multiple cardiac phases. Strain-encoded CMR with DENSE has high spatial (3.2 mm × 3.2 mm × 8 mm) and temporal resolution (TR= 27.34 ms). We aimed to measure myocardial strain values with DENSE in healthy adults across a broad age range at 3.0 Tesla. Methods Healthy volunteers with no prior medical history or treatment were enrolled and underwent CMR at 3.0T (Magnetom Verio, Siemens healthcare, Erlangen, Germany). Mid-left ventricular short axis and horizontal long axis DENSE sequences were acquired and analysed using CIM_DENSE2D software (University of Auckland, New Zealand and Siemens Healthcare). Segmental and global myocardial circumferential (Ecc) and longitudinal (Ell) strain were obtained. Results Ecc and Ell were analysed in 77 volunteers (mean age 45 ± 18 years, 49% male) (Table 1). Mean Ecc strain was greater in women than in men. These sex-differences were mainly related to strain values in the anterior and antero-lateral LV segments. There is no difference for Ell. Conclusion Left ventricular circumferential contractility differs between men and women, and the differences were regionalised to the antero-lateral myocardial regions where LV displacement is greatest. Funding Medical Research Scotland project grant. Professor Berry was supported by a Senior Clinical Fellowship from the Scottish Funding Council.

There have been a number of physiological and anatomical reports on the lateral pterygoid muscle. They include some unclear points, and no agreement has been reached from the results so far. Most of the pevious studies have been performed by the lateral approach. Few reports have been made by the superior approach which is useful for investigation of the muscle.We dissected 26 temporomandibular joints from 14 adult cadavers by the superior approach and studied the muscle, as well as its functions, reviewing the literature.The lateral pterygoid muscle varied with the cadaver in the number of the head as follows; 7.7% of all specimens had single head, 3.8% had the lateral and medial heads, 57.6% had the superior and inferior heads, and 30.7% had three heads, i.e. superior, inferior and medial. This result indicates that the lateral pterygoid muscle was substantially different from cadaver to cadaver. The muscle fibers were so crowded with each other and with those of the temporal muscle that only 8 cases had the superior and inferior head's muscle which could be completely separated from each other. The superior head laid at an angle of 7.0 degrees medially with respect to the line perpendicular to the horizontal long axis of the mandibular head, the inferior head was at an angle of 19.1°, and the medial head was at an angle of about 37.7° to this reference line, on average. The superior head of the muscle was attached to the pterygoid fovea of the mandibular head except that the superficial layer of the superior head was attached to the inferior surface of the disk. The medial head of the muscle appeared to be inserted into the medial border of the disk and the medial capsule. In addition to the lateral pterygoid muscle, the temporal muscle of some specimens were attached to the anterosuperior stratum of the disk through the fibrous tissues and, sometimes, directly to the anterolateral part of the disk.We support, in principle, the previous reports that the lateral pterygoid muscle has generally two heads. We observed that, however, many variations of the muscle existed in terms of the individual their age, and their sex, and that the muscle fibers considerably crossed each other. Therefore, although we cannot deny the possibility that the superior head and inferior head of the lateral pterygoid muscle would function differently, we do not support that the superior and inferior heads of the muscle move antagonistically on electromyogram.

Introduction Standard MRI assessment of right ventricular (RV) volume and mass is based on assessment of a stack of "standard" short axis images (fig. 1) obtained with respect to the horizontal long axis of the heart. A "modified" RV short axis stack of images, based on cross-sections of the RV outflow long axis (fig. 2), has recently been demonstrated to overcome observed inaccuracies in definition of the tricuspid valve plane for the "standard" image stacks, and therefore to result in less interobserver variability and more reliable RV volume estimates in subjects with anatomically and functionally normal RVs.