Low Interobserver Variability Research Articles

119 Proposal of a new technique for evaluating the total liver blood flow volume during pregnancy by doppler sonography

Introduction Estimation of the total liver blood flow volume by Doppler sonography during pregnancy might be a promising tool in the assessment of patients with severe PE/HELLP syndrome. The usual Doppler technique does not individual variations in vessel’s diameter. We believe this can be an important source of measurement bias. Objective To propose an improvement in the Doppler technique for evaluation of hepatic total blood flow during pregnancy. Method 55 normal pregnant women were included and signed informed consent. They were fasting for at least 6 h. The standard Doppler method of estimating flow volume does not consider variations in vessel’s diameter, the sample volume is set at 3,0 mm. We propose to measure the vessel’s diameter and to adjust the sample volume so that it occupies the entire vessel lumen. The volume flow should be calculated more accurately as the different speeds of the red blood cells are considered, instead of the speeds of the center of the vessel. Reproducibility was tested by interobserver and intraobserver variabilities. Two experienced examiners (A and B) performed all tests. Doppler sonography of the portal vein and the common hepatic artery were performed in the same woman three times by examiner A and three times by examiner B. Intraobserver variability was verified with the values obtained in the first and last measurements (supposed worst and best values). Variables analyzed were: portal vein (PV) flow volume A1 and A3, B1 and B3; common hepatic artery (CHA) flow volume A1 and A3, B1 and B3. Possible differences between the two observers were tested using the mean values obtained by each observer. We also calculated the intraclass correlation coefficient (ICC). Variables analyzed were: PV caliber A and B; CHA caliber A and B; Mean PV flow volume A and B; Mean CHA flow volume A and B. The statistical tests used for intra and interobserver variability testing were Stuart’s paired T-test, Pearson’s correlation coefficient and Blan–Altman’s plots of differences. Results Data was available for 50 women. We could not perform complete examination in 5 patients. Technical difficulties were mainly due to obesity, gas, and woman‘s intolerance to supine position. Women‘s mean age was 28y (18y–40y) and mean gestational age was 28w (20w–36w). We found low intraobserver and interobserver variability as demonstrated by paired T test and correlation coefficients in table 1. ICC for observer 1 was 0.982 for PV FV and 0.997 for CHA FV. ICC for observer 2 was 0.984 for PV FV and 0.998 for CHA FV. Conclusion The improvement we propose for Doppler assessment of the total hepatic blood flow in pregnancy has good intra and interobserver reproducibility. These results encourages us to continue research and to propose this method as preffered in pregnancy.

Evaluation of blood flow distribution asymmetry and vascular geometry in patients with Fontan circulation using 4-D flow MRI.

Asymmetrical caval to pulmonary blood flow is suspected to cause complications in patients with Fontan circulation. The aim of this study was to test the feasibility of 4-D flow MRI for characterizing the relationship between 3-D blood flow distribution and vascular geometry. We hypothesized that both flow distribution and geometry can be calculated with low interobserver variability and will detect a direct relationship between flow distribution and Fontan geometry. Four-dimensional flow MRI was acquired in 10 Fontan patients (age: 16 ± 4years [mean ± standard deviation], range: 9-21years). The Fontan connection was isolated by 3-D segmentation to evaluate flow distribution from the inferior vena cava (IVC) and superior vena cava (SVC) to the left and right pulmonary arteries (LPA, RPA) and to characterize geometry (cross-sectional area, caval offset, vessel angle). Flow distribution results indicated SVC flow tended toward the RPA while IVC flow was more evenly distributed (SVC to RPA: 78% ± 28 [9-100], IVC to LPA: 54% ± 28 [4-98]). There was a significant relationship between pulmonary artery cross-sectional area and flow distribution (IVC to RPA: R(2)=0.50, P=0.02; SVC to LPA: R(2)=0.81, P=0.0004). Good agreement was found between observers and for flow distribution when compared to net flow values. Four-dimensional flow MRI was able to detect relationships between flow distribution and vessel geometry. Future studies are warranted to investigate the potential of patient specific hemodynamic analysis to improve diagnostic capability.

Quantitative analysis of ex vivo colorectal epithelium using an automated feature extraction algorithm for microendoscopy image data.

Qualitative screening for colorectal polyps via fiber bundle microendoscopy imaging has shown promising results, with studies reporting high rates of sensitivity and specificity, as well as low interobserver variability with trained clinicians. A quantitative image quality control and image feature extraction algorithm (QFEA) was designed to lessen the burden of training and provide objective data for improved clinical efficacy of this method. After a quantitative image quality control step, QFEA extracts field-of-view area, crypt area, crypt circularity, and crypt number per image. To develop and validate this QFEA, a training set of microendoscopy images was collected from freshly resected porcine colon epithelium. The algorithm was then further validated on ex vivo image data collected from eight human subjects, selected from clinically normal appearing regions distant from grossly visible tumor in surgically resected colorectal tissue. QFEA has proven flexible in application to both mosaics and individual images, and its automated crypt detection sensitivity ranges from 71 to 94% despite intensity and contrast variation within the field of view. It also demonstrates the ability to detect and quantify differences in grossly normal regions among different subjects, suggesting the potential efficacy of this approach in detecting occult regions of dysplasia.

Validation of a Novel 3-Dimensional Sonographic Method for Assessing Gastric Accommodation in Healthy Adults.

A novel automated 3-dimensional (3D) sonographic method has been developed for measuring gastric volumes. This study aimed to validate and assess the reliability of this novel 3D sonographic method compared to the reference standard in 3D gastric sonography: freehand magneto-based 3D sonography. A prospective study with 8 balloons (in vitro) and 16 stomachs of healthy volunteers (in vivo) was performed. After a 500-mL liquid meal, 1 preprandial and 3 postprandial volume scans of the stomachs were performed by the novel 3D sonographic method and the current reference-standard 3D sonographic method. The in vitro study showed a mean volume difference between the novel method and the true balloon volume of -1.3 mL; limits of agreement (LoA) were small (-39.3 to12.3 mL), with an intraclass correlation coefficient (ICC) of 0.998. The in vivo study showed a mean gastric volume of 321 mL between the novel method and the freehand magneto-based method, with a mean volume difference of -4.4 mL; LoA were -40.1 to 31.2 mL, and the ICC was 0.991. The intraobserver and interobserver variability rates were low, at 0.8 mL (LoA, -24.0 to 25.6 mL), with an ICC of 0.995, and 0.5 mL (LoA, of -26.8 to 27.8 mL), with an ICC of 0.999, respectively. The novel 3D sonographic method with automated acquisition showed good agreement with the current reference-standard gastric 3D sonographic method, with low intraobserver and interobserver variability. This novel 3D sonographic method is a valid and reliable technique for determining gastric accommodation.

Interobserver Variability of Ki-67 Measurement in Breast Cancer

Background:As measurement of Ki-67 proliferation index is an important part of breast cancer diagnostics, we conducted a multicenter study to examine the degree of concordance in Ki-67 counting and to find factors that lead to its variability.Methods:Thirty observers from thirty different institutions reviewed Ki-67–stained slides of 20 different breast cancers on whole sections and tissue microarray (TMA) by online system. Ten of the 20 breast cancers had hot spots of Ki-67 expression. Each observer scored Ki-67 in two different ways: direct counting (average vs. hot spot method) and categorical estimation. Intraclass correlation coefficient (ICC) of Ki-67 index was calculated for comparative analysis.Results:For direct counting, ICC of TMA was slightly higher than that of whole sections using average method (0.895 vs 0.858). The ICC of tumors with hot spots was lower than that of tumors without (0.736 vs 0.874). In tumors with hot spots, observers took an additional counting from the hot spot; the ICC of whole sections using hot spot method was still lower than that of TMA (0.737 vs 0.895). In categorical estimation, Ki-67 index showed a wide distribution in some cases. Nevertheless, in tumors with hot spots, the range of distribution in Ki-67 categories was decreased with hot spot method and in TMA platform.Conclusions:Interobserver variability of Ki-67 index for direct counting and categorical estimation was relatively high. Tumors with hot spots showed greater interobserver variability as opposed to those without, and restricting the measurement area yielded lower interobserver variability.

Utility of Colonoscopy to Exclude Underlying Malignant Polyps After Resolution of Uncomplicated Diverticulitis

intervention, or monitoring.3 After resolution of an episode of diverticulitis, the standard of care is to perform a colonoscopy to exclude diagnoses that mimic diverticulitis—notably, colorectal cancer. This recommendation arose during a time when the diagnosis rested on clinical suspicion and radio­ graphic imaging with barium.4 Computed tomog­ raphy, with a substantially higher sensitivity than barium enema5 at diagnosing cancer and other ab­ dominal pathologic conditions, is now the primary modality used to define complicated diverticulitis, with low interobserver variability and a sensitivity and specificity approaching 99%.6 Computed tomo­ graphic findings in complicated diverticulitis in­ clude abscess, fistula, stricture, extensive stranding, obstruction, or air (ie, perforation); colonic wall thickening and mass lesions are concerning radio­ logic features for neoplasia. The current Clinical Guideline Task Force of the American Society of Colon and Rectal Surgeons recommends that “after resolution of acute diverticu­ litis, perform colonoscopy in 6 to 8 weeks following resolution, to confirm diagnosis; if this is first epi­ sode or recent colonoscopy has not been done” Utility of Colonoscopy to Exclude Underlying Malignant Polyps After Resolution of Uncomplicated Diverticulitis

CraMs: Craniometric Analysis Application Using 3D Skull Models.

Craniometric analysis plays an important role in anthropology studies and forensics. This paper presents CraMs, an application using a new craniometric approach based on 3D models of the skull. The main objective is to obtain, through a process supervised by anthropologists, the main points of interest used to compute craniometric measurements. The application aids this process by analyzing the skull geometry and automatically providing points of interest. The application also allows for semiautomatic point detection, where the user provides an initial guess that might be refined based on the curvature of the skull, as well as the manual selection of any other points of interest. Moreover, results comparing measurements obtained with CraMs and traditional craniometry methods on eight skulls suggest that the application provides comparable craniometric measurements and lower inter-observer variability. This approach offers advantages such as an easier access to skulls with no risk of bone damage and the possibility of defining new measurements based on morphology or other skull characteristics, which are not possible using traditional methods.

Prostate cancer: contouring target and organs at risk by kilovoltage and megavoltage CT and MRI in patients with and without hip prostheses.

In radiotherapy treatment, planning target volume and organs at risk are contoured on kilovoltage CT (kVCT) images. Unlike MR images, kVCT does not provide precise information on target volume extension. Since neither kVCT nor MRI may be suitable for contouring in patients with ferrous hip prostheses, this study evaluated whether megavoltage CT (MVCT) reduced interobserver variability. Two patients without hip prostheses and one patient (Patient 3) with hip prostheses were enrolled. Six radiation oncologists contoured prostate, rectum and bladder on kVCT (Patients 1 and 3), MRI (Patient 2) and MVCT images (Patient 3). MVCT was acquired with fine, normal and coarse modalities. Interobserver variability for each organ was analysed using conformity index (CI) and coefficient of variation (CV). In patients without hip prostheses, CIs were higher in prostate contouring with MRI than with kVCT, indicating lower interobserver variability with MRI. Very slight variations were seen in rectum and bladder contouring. In the patient with hip prostheses (Patient 3), contouring on kVCT lowered CI and increased CV in the prostate, bladder and rectum. The differences were more marked in the prostate. Only fine modality MVCT reduced interobserver variability and only for the prostate. Even though greater noise and less soft-tissue contrast increase contouring variability with MVCT than with kVCT, lack of artefacts on MVCT could provide better image definition by this modality in hip prosthesis patients in whom MRI is precluded. We recommend the fine modality MVCT for contouring hip prostheses patients.

Reproducibility and interobserver variability of systolic blood flow velocity and 3D wall shear stress derived from 4D flow MRI in the healthy aorta.

To investigate the reproducibility and interobserver variability of 3D aortic velocity vector fields and wall shear stress (WSS) averaged over five systolic timeframes derived from noncontrast 4D flow magnetic resonance imaging (MRI). Fourteen controls underwent test-retest 4D flow MRI examinations separated by 16 ± 3 days (resolution = 3.0-3.6 × 2.3-2.6 × 2.5-2.7 mm(3) ; TE/TR/FA = 2.5/4.9 msec/7°; Venc = 150 cm/s). Two observers segmented the aorta, and WSS was calculated for both series of scans and both segmentations. Test-retest and interobserver velocity and WSS vectors were compared on a voxel-by-voxel basis in the aorta and on a regional basis by subdividing the aortas in six segments. Test-retest: voxel-by-voxel Bland-Altman analysis revealed small differences (-0.03/-0.02 m/s/Pa), limits of agreement (LOA) of 0.25 m/s/0.29 Pa, and coefficients of variation (CV) of 20% for velocity/WSS. Voxel-by-voxel orthogonal regression analysis showed moderate agreement (slope: 1.14/1.16, intraclass correlation coefficient [ICC]: 0.76/0.67 for velocity/WSS). The regional analysis revealed a CV of 9%/8% and ICC of 0.9/0.9 for velocity/WSS. Interobserver: voxel-by-voxel difference for WSS was 0, LOA: 0.17/0.19 Pa, CV: 12/13%, slope: 1.01/1.09, ICC: 0.87/0.85 for test/retest. The CV/ICC for WSS in the regional analysis was 4%/1.0 for test and 3%/1.0 for retest. Systolic velocity and WSS derived from 4D flow MRI are reproducible between consecutive visits, with low interobserver variability in healthy volunteers.

Left Ventricle Assessment-Ejection Fraction and Stroke Volume Through Simpson’ Method and 3D Transthoracic Echocardiography in Patients with Aortic Valve Disease

Objective: Assessment of ejection fraction (EF) results from Simpson’ method from 2D and 3D transthoracic echocardiography (TTE). In addition, it was also assessed stroke volume (SV) from 2D TTE and 3D TTE. Background: The reference method to calculate LV volumes, SV and EF is cardiac magnetic resonance imaging (MRI). However there are other useful methods such as Simpson’ method by 2D TTE and 3D TTE. Method and Results: Thirty patients were examined. EF was calculated by 2D TTE and was compared with 3D TTE result. SV was calculated by 2D TTE using the following formula: and the final results were compared with 3D TEE results. Results: Were found significant differences related with EF and SV between 2D TTE and 3D TTE. Low inter-observer variability was obtained (coefficient of variability 6%). Both methods presented a strong correlation (ICC was 70% between 2D TTE and 3D TTE in EF measurement and ICC of 71% between those two in SV measurement). Conclusion: 3D TTE presents higher EF results then 2D TTE and has a strong correlation. In the other hand, 3D TTE presents lower SV results comparing with LVOT measurement, having a strong correlation. The inter-observer variability coefficient by 2D TTE was low.

Abstract PD1-3: The significance of tumor infiltrating lymphocyte density, subset composition and organization in breast cancer

Abstract The clinical relevance of tumor infiltrating lymphocytes (TIL) in breast cancer (BC) has been clearly established by recent large clinical trials (presented at SABCS 2013). The relationship between protective immunity, observed in some patients, and critical features of lymphoid subset composition and organization remain unknown. Our recent work revealed that tertiary lymphoid structures (TLS), principally composed of T cells, B cells and dendritic cells, are present in the peri-tumoral regions of breast tumors and associated with a CD4+ follicular helper T (Tfh) cell presence. Through retrospective analyses, we determined that TLS were associated with good clinical outcomes in both the neo-adjuvant and adjuvant settings. To gain insight into the immune components linked with a significant TIL and TLS presence, we initiated a prospective flow cytometric study. We systematically immunophenotyped T and B cell TIL in breast tissues from tumors (n=125), non-adjacent non-tumor tissues (NANT, n=115) and normal tissue from mammary reductions (n=26) on the day of surgery. TIL organization and spatial distribution was subsequently analyzed by immunohistochemistry (IHC) and immunofluorescence (IF) on paraffin sections for a subset of patients (n=78). The fresh tissue analyses revealed that TIL density was a continuum across the 125 patients analyzed. A cutoff for TIL-positive and -negative tumors was set at 58 CD45+ TIL per mm3 of tissue based on the number of CD45+ cells present in the remarkably similar normal and NANT tissues. Applying this threshold to BC, 65% were TIL-positive with approximately one-third considered extensively infiltrated. TIL-positive tumors are characterized by an increase in CD4+ T cells and CD19+/CD20+ B cells. The median CD4/CD8 ratio was >1 in TIL-positive compared to <1 in TIL-negative tumors and NANT. CD4+ and CD8+ T cells were predominantly CD45RO+ memory cells, with a significant proportion expressing PD-1. Infiltrating B cells were approximately 50% memory cells in contrast to <15% in normal and NANT tissues. Extensively infiltrated tumors were more frequently associated with Tfh and follicular B cells resident in TLS. IF analysis by confocal microscopy found that TLS resident cells included specific lymphocyte subsets: marginal B cells (CD20+CD27+IgD−), follicular mantle B cells (CD20+IgD+), germinal center B cells (CD20+Ki67+CD35+CD21+PD-1+) and germinal center Tfh cells (CD4+CD200+TIGIT+CXCL13+) in a B cell zone surrounded by a T cell zone containing CD4+ and CD8+ T cells. To determine whether the flow cytometry data was correlated with routine pathology, sections of the same tumors were stained by H&E and CD45 (total leukocytes) or CD3 plus CD19 (T cells + B cells; >95% of CD45+ cells) IHC and scored by trained pathologists. The best correlation was observed between CD3/CD20 flow cytometry and CD3/CD19 IHC, the latter also associated with lower inter-observer variability. TIL density was positively correlated with proliferation (Ki67 & histological grade) and hormone receptor negativity while TLS were more frequent in younger women. These data suggest that organized immune responses in TLS adjacent to the tumor bed provide an effective location for generating anti-tumor memory T and B cell responses. Citation Format: Karen Willard-Gallo, Laurence Buisseret, Soizic Garaud, Chunyan Gu-Trantien, Alexandre de Wind, Sébastien Duquenne, Denis Larsimont, Christos Sotiriou, Martine Piccart. The significance of tumor infiltrating lymphocyte density, subset composition and organization in breast cancer [abstract]. In: Proceedings of the Thirty-Seventh Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2014 Dec 9-13; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2015;75(9 Suppl):Abstract nr PD1-3.

QUANTITATIVE APPROACH TO ASSIST NEUROBLASTOMA ASSESSMENT BY MEASURING I-123 mIBG UPTAKE IN SCINTIGRAPHIC IMAGES

Whole-body 123I-Metaiodobenzylguanidine (mIBG) scintigraphy is used as the primary image modality in neuroblastoma detection. It is the most sensitive and specific method for staging and response evaluation. Validated semi-quantitative scoring methods with low interobserver variability and high reproducibility have shown to be indispensable for the evaluation of response to therapy. However, low resolution, noise and acquisition difficulties, specially in children, make low definition scans. These facts increase observer dependent interpretations that limit assessment and complicate to put a scoring method successfully into practice. It is essential to have an objective and reliable measure of response to test the activity of therapies. In this paper we propose the use of a quantitative observer-independent measurement of the strength of uptake to be used as an additional tool for assisting the International Society of Paediatric Oncology Europe Neuroblastoma Group (SIOPEN) semi-quantitative scoring method. This is the scoring method recommended by the SIOPEN Nuclear Medicine and Physics Committee, in collaborative work with the Children’s Oncology Group, as the standard one for acquiring and reporting diagnostic paediatric mIBG scans across Europe. Our proposed method is based on the ratio between the amount of specific uptake at tumours and the amount of non-specific uptake at SIOPEN anatomical sectors which has shown to be constant in all the scans of the patients.

Visual assessment of Ki67 using a 5-grade scale (Eye-5) is easy and practical to classify breast cancer subtypes with high reproducibility

AimsPersonalised breast cancer therapy requires pathological characterisation of tumours. The proliferative index, based on Ki67, is pivotal, but a standard method has not been established. Here we look for an...

Automatic scar segmentation in dual inversion recovery images is more consistent with manual outlining than in conventional inversion recovery images

Background The dual inversion recovery (dual IR) pulse sequence has recently been shown to improve blood suppression and infarct delineation in late gadolinium enhancement (LGE) images of myocardial infarction. This resulted in significantly lower inter-observer variability in manual outlining of scar and higher expert confidence in scar detection and transmurality when compared with conventional inversion recovery (IR) images. Computer algorithms have been shown to improve the accuracy of scar segmentation within IR images. We sought to develop and optimise a set of computer algorithms to quantify scar in both IR and dual IR images. Methods

Outcomes of Traumatic Aortic Injury in a Primary Open Surgical Approach Paradigm.

Background:Multiple classifications can be used to define the magnitude of aortic injury. The Vancouver Classification (VC) is a new and simplified computed tomography-based Blunt Aortic Injury (BAI) grading system correlating with clinical outcomes.Objectives:The objectives of this study are: 1) to describe the severity of aortic injury in a center with a predominantly surgical approach to BAI; 2) to correlate the severity of aortic trauma to hospital survival rate and rate of adverse events according to the type of interventions performed during the hospital stay; and 3) to evaluate VC.Patients and Methods:All patients referring to the Sacre-Coeur Hospital of Montreal between August 1998 and April 2011 for management of BAI were studied. Two radiologists reviewed all CT scan images individually and classified the aortic injuries using VC.Results:Among the 112 patients presenting with BAI, 39 cases had local CT scans available for reconstruction. Seven patients were identified as suffering from grade I injuries (flap or thrombus of less than 1 cm), 6 from grade II injuries (flap or thrombus of more than 1 cm), and 26 from grade III injuries (pseudoaneurysm). Among the patients with grade I injuries, 57% were treated surgically and 43% medically with a survival rate of 100%. Among the patients with grade II injuries (67% treated surgically and 33% treated medically) survival was also 100%. Among patients with grade III injuries (85% treated surgically, 7% had Thoracic Endovascular Aortic Repair (TEVAR) and 8% treated medically) survival was 95%, 95% and 50%, respectively. There were no significant differences between groups as to clinical outcome. Inter-rater reliability was 0.81.Conclusions:VC is easy to use and has low inter-observer variability. Low grades of injury were associated with low mortality related to medical treatment.

Assessment of Magnetic Resonance Imaging Artifact Following Cervical Total Disc Arthroplasty.

Cervical disc arthroplasty has become a technique for the treatment of cervical degenerative disc disease. Clinically, the need to accurately assess the neural elements at the operative and adjacent levels is critical postoperatively. The purpose of this study was to quantitatively and qualitatively measure the amount of MRI artifact produced by various cervical total disc replacements. T1 and T2-weighted turbo spin-echo MRI sequences were collected on the cervical spine (C2-T1) of a 68 year-old unembalmed male cadaver. A discectomy was performed at C5-6, followed by successive implantation of six different total disc replacements. The scans were quantitatively evaluated by three of the authors. The volume of artifact was measured using image analysis software. Qualitative analysis of the adjacent and index neural elements was performed. The artifact in the T2 weighted images was noted to be 58.6±7.3 cm3 for Prestige ST, 14.2±1.3 cm3 for ProDisc-C, 7.5±0.8 cm3 for Discover, 8.0±0.3 cm3 for Prestige LP, 6.6±0.7 cm3 for Bryan, and 7.3±0.6 cm3 for ProDisc-C titanium prototype. Acceptable intraobserver and excellent interobsever correlation was demonstrated using Pearson Correlation and Concordance Correlation Coefficient analysis. The adjacent and implanted level neural elements (spinal cord and neuroforamina) were easily visualized on the T2 weighted images after the implantation of titanium devices (ProDisc-C titanium prototype, Discover, Prestige LP and Bryan). After implantation of a cobalt chrome implant (ProDisc-C), the adjacent level neural elements were easily visualized but the implanted level could not be fully visualized due to distortion of the images. The quality of the distortion was least favorable after the implantation of the stainless steel implant (Prestige ST), where neither the adjacent nor the index level could be fully visualized. The volume of the artifact seen following cervical total disc arthroplasty is highly dependent upon the material property of the implant. Quantitative analysis described in this study demonstrated sufficiently low intraobserver and interobserver variability to be considered a reliable technique.

0179: Assessment of paravalvular aortic regurgitation after transcatheter aortic valve implantation using cardiac magnetic resonance imaging: a comparative study with echocardiography and angiography

Assessment of paravalvular aortic regurgitation (AR) after transcatheter aortic valve implantation (TAVI) using Edwards SAPIEN XT valve remains challenging using transthoracic echocardiography (TTE) or angiography. Cardiac magnetic resonance imaging (c-MRI) has a low intraobserver and interobserver variability in the assessment of regurgitant volumes and might be more reliable to assess AR post-TAVI. We therefore aimed to evaluate the value of c-MRI to assess paravalvular AR after TAVI. Between February 2012 and March 2013, 132 consecutive patients underwent successful TAVI using exclusively Edwards SAPIEN XT prosthesis. AR was evaluated by c-MRI, TTE and angiography in 45 patients (27 women, mean age 84.1±7.1 years). Angiography was performed immediately after TAVI whereas TTE and c-MRI were performed one month after implantation. At baseline c-MRI, the mean aortic regurgitant fraction (ARF) was 21.3±12.5%. A significant AR (> grade II) was present in 24 (56%) patients using c-MRI (30< ARF>50 Y%) whereas it was only observed in 18 (40%) and 12 (27%) patients using TTE and angiography, respectively. Interestingly, there was a poor correlation between c-MRI and TTE (r=0.16, p=0.28) and between c-MRI and angiography (r=0.30, p=0.06). In contrast, there was a good correlation between TTE and angiography (r=0.6, p<0.001). TTE underestimated AR by one degree in 9 patients, and by two degrees in 6 patients as compared to c-MRI. The results of our study suggest that TTE and angiography may underestimate the severity of AR after TAVI as compared to c-MRI. Furthermore, there is a poor correlation between c-MRI and TTE or angiography. Further studies are mandatory to confirm our results in a larger population.

Calculation of Pediatric Left Ventricular Mass: Validation and Reference Values Using Real-Time Three-Dimensional Echocardiography

Reference values for left ventricular mass (LVM) are important echocardiographic tools for the follow-up of pediatric patients with cardiac disease. Cardiac magnetic resonance (CMR) imaging is currently regarded as the gold standard. The aims of this study were to validate LVM calculated using real-time three-dimensional echocardiography (RT3DE) and to establish pediatric reference values. For validation, 40 subjects (20 patients) consecutively underwent CMR (3-T TX Achieva, 25 cardiac phases/slice) and RT3DE (iE33 or Vivid E9, four subvolumes) in a single-center approach. The quantification of CMR data by the disk summation method as standard (mean LVM, 84.2 ± 53 g; range, 17.7-231.7 g) was compared with RT3DE. In a multicenter prospective design, 434 healthy children were investigated using standard software (LV-Analysis version 3.1). In comparison with CMR, RT3DE provided a slight overestimation of LVM of only 2.5 ± 11.3% (r = 0.990, intraclass correlation coefficient = 0.995), and there was low intraobserver (mean, 0.9 ± 7.1%; scatter, 13.2% to -15.0%; r = 0.996; intraclass correlation coefficient = 0.998) and interobserver (mean, 1.5 ± 9.3%; scatter, 17.2% to -20.1%; r = 0.993; intraclass correlation coefficient = 0.996) variability. Feasibility of the multicenter approach was 76%, resulting in 332 healthy children (median age, 10.0 years; range, 0-18 years; group I range, 0-6 years; group II range, 7-18 years) with data sets providing adequate image quality. LVM was correlated with sex (group II), age (r = 0.901), height (r = 0.881), weight (r = 0.876), and body surface area (r = 0.898). Unisex percentiles for 0 to 6 years of age and separated according to gender from 7 to 18 years of age were established. Mean calculation time for RT3DE was <3 min. In children, LVM calculation presuming excellent real-time three-dimensional echocardiographic data sets is accurate, quick, and reproducible. The percentiles provided are based on a large sample size and may be useful for clinical practice.

Carotid plaque morphometric assessment with three-dimensional ultrasound imaging

As investigations into nonsurgical treatment for atherosclerosis expand, the measurement of plaque regression and progression has become an important end point to evaluate. Measurements of three-dimensional (3D) plaque volume are more reliable and sensitive to change than are traditional estimates of stenosis severity or cross-sectional area. 3D ultrasound (3D US) imaging may allow monitoring of plaque volume changes but has not been used routinely due to the cumbersome motorized units required to drive transducers. We investigated the variability, reliability, and the least amount of change detectable by 1D plaque measures, as well as 2D and 3D measures of plaque morphometry, that can be applied in a clinical environment. 3D US imaging was obtained in 10 patients with carotid stenosis. The lumen and outer wall boundaries were outlined in serial cross-sectional images 1 mm apart. Three observers manually segmented vessel wall volumes (VWVs), and the segmentation was repeated again 4 weeks later. This allowed measurement of interobserver and intraobserver variability of 6 pairs of observations. We measured Bland-Altman statistics, intraclass correlation coefficients, coefficient of variability, and the minimum detectable plaque change for each morphometric measure. The mean VWV of carotid lesions in the study was 1276.8 mm(3) (range, 620.6-1956.3 mm(3)). Bland-Altman plots demonstrated low interobserver and intraobserver variability. The interobserver variability of volume measurements as a function of mean volume was 14.8% and interobserver variability was 8.9%. Reliability was 87% as quantified by the interclass correlation and was 95% by the intraclass correlation. The least detectable change in VWV was 12.9% for interobserver variability and 4.5% for intraobserver variability for the three observers. Carotid plaque diameter measurements from B-mode images have high variability. Plaque burden, as estimated by VWV, can be measured reliably with a 3D US technique using a clinical scanner. The volumetric change, with 95% confidence, that must be observed to establish that a plaque has undergone growth or regression is ∼12.9% for different observers and 4.5% for the same observer performing the follow-up study.

Removal due to cut-out effect in pertrochanteric femoral fractures: What is the rescue treatment of choice?

ObjectiveThe goal of the study was to compare functional results in different treatment options in cutting-out, and analyze factors associated to failure. Materials and methodsRetrospective cohort study in 56 patients diagnosed with cutting-out between 2000 and 2010. Groups were based on rescue treatment: arthroplasty versus alternative treatment. Demographics, fracture characteristics, osteosynthesis, tip to apex distance (TAD), follow-up, complications, and final functional capacity were analyzed. ResultsRescue treatment: 36 (64.28%) hip replacement (arthroplasty group) and 20 (35.72%) alternative treatment preserving femoral head (alternative group). Groups were comparable on demographic parameters, fracture pattern and osteosynthesis characteristics. Radiography analysis: low inter-observer variability (k=0.83, 95% CI 0.78–0.88), mean TAD 28.66mm (arthroplasty group 32.9mm, 21.5mm control group; p=0.01), and insufficient fracture reduction 39.3% (p=0.001). Cutting-out diagnosis median was 60 days (arthroplasty group 90 days, 18 days alternative group; p=0.001). Follow-up was at least 12 months from rescue treatment. Similar complications rate was observed in both groups (p=0.16). Re-operation rate was 3.57% (11.7% arthroplasty group, alternative group 0%; p=0.01). Better final functional capacity was observed in arthroplasty group (p=0.004). DiscussionHip arthroplasty offers better results, being considered the gold standard in geriatric patients, although re-operation rate is higher. We recommend new nailing before arthroplasty in early failure (4 weeks) in patients with femoral head integrity. An insufficient fracture reduction is the main short-term factor predicting failure; and TAD higher than 20mm is a middlelong-term one.