Abstract 16230: Pulmonary Autograft Wall Stresses One Year After Ross Operation

Circulation ◽  
2020 ◽  
Vol 142 (Suppl_3) ◽  
Author(s):  
Edgardo Alonso ◽  
Yue XUAN ◽  
Alexander Emmott ◽  
Zhongjie Wang ◽  
Shalni Kumar ◽  
...  
Keyword(s):  
Ascending Aorta ◽  
Patient Specific ◽  
Principal Stresses ◽  
Ross Operation ◽  
Children And Young Adults ◽  
Specific Material ◽  
One Year ◽  
Patients Experience

Introduction: The Ross procedure is an excellent option for children and young adults who need aortic valve replacement as this surgery can restore patient survival to that of a normal sex and aged-matched population. However, some patients experience aneurysmal formation during autograft remodeling and require reoperation. As the underlying biomechanics of autograft remodeling are unknown, we investigated patient-specific wall stresses in pulmonary autografts one year post-operatively to better understand systemic pressure-driven early autograft wall stresses. Methods: Ross patients (n=16) who underwent intraoperative collection of pulmonary root/aortic specimen, and subsequent one-year MRI follow-up were recruited. Patient-specific material properties from their tissue were experimentally determined and incorporated into autograft ± Dacron and ascending aorta finite element models. A multiplicative approach was used to account for pre-stress geometry from in-vivo MRI. Physiologic pressure loading was simulated with LS-DYNA software. Results: At systemic systole, first principal stresses were 567kPa (25-75% IQR, 485-675kPa), 809kPa (691-1219kPa), and 382kPa (334-413kPa) at autograft sinuses, sinotubular junction (STJ), and ascending aorta, respectively. Second principal stresses were 355kPa (320-394kPa), 360kPa (310-426kPa), and 184kPa (147-222kPa) at autograft sinuses, STJ, and ascending aorta, respectively. Mean autograft diameters were 38.3±5.3mm, 29.9±2.7mm, and 26.6±4.0mm at sinuses, STJ, and annulus, respectively. Conclusions: First principal stresses were mainly located at STJ, particularly when Dacron reinforcement was applied to constrain STJ dilatation. However, at one-year after the Ross operation, autograft dilatation was not seen despite elevated autograft wall stresses compared to their internal controls, the lower wall stresses in corresponding native distal ascending aorta. In this group of patients, higher risk of dilatation is expected in the sinuses and STJ if not constrained by Dacron than the corresponding ascending aorta. Future follow-up will elucidate the biomechanics of long-term autograft remodeling to develop predictive models for autograft dilatation.

Anterior Mediastinal Paraganglioma Mimicking Thymoma

2012 ◽  
Vol 15 (3) ◽  
pp. 170
Author(s):  
Hee Moon Lee ◽  
Dong Seop Jeong ◽  
Pyo Won Park ◽  
Wook Sung Kim ◽  
Kiick Sung ◽  
...  
Keyword(s):  
Mediastinal Mass ◽  
Aortic Wall ◽  
Anterior Wall ◽  
Ascending Aorta ◽  
Anterior Mediastinal Mass ◽  
Arterial Reconstruction ◽  
Ct Evaluation ◽  
One Year ◽  
Mediastinal Paraganglioma

A 54-year-old man was referred to our institution with hemoptysis and hoarseness of 1 year's duration. A computed tomography (CT) scan showed an anterior mediastinal mass (2.5 cm x 1.0 cm), which was diagnosed as thymoma. The tumor was resected under a sternotomy. The tumor had invaded the anterior wall of the ascending aorta. With the patient under cardiopulmonary bypass, the aortic wall invaded by the mass was resected, and arterial reconstruction was performed with patch material. The tumor was revealed to be a tumor of neuronal origin. The patient's postoperative course was uneventful. The patient was discharged on postoperative day 9. One year after the operation, a follow-up chest CT evaluation showed no specific complications or recurrence.

Individualized Behavioural Treatment of Severe Stuttering

1991 ◽  
Vol 19 (4) ◽  
pp. 347-357 ◽  
Author(s):  
Willi Ecker ◽  
Victor Meyer
Keyword(s):  
Oral Reading ◽  
Reading Improvement ◽  
Behavioural Treatment ◽  
Communication Situations ◽  
Cognitive Techniques ◽  
One Year

This case study illustrates the reduction of severe stuttering by an individually tailored treatment programme. Interventions are derived from a tripartite analysis (Lang, 1971) and include EMG biofeedback, regulated breathing, exposure in vivo to stressful communication situations and cognitive techniques to reduce relapse risk. The role of dysfunctional response system interactions in stuttering is emphasized. Treatment resulted in a marked reduction of stuttering and associated facial contortions during videotaped conversations with strangers and oral reading. Improvement was maintained at one-year follow-up.

A Successful Adaptation of Systematic Desensitization in the Treatment of a Phobia of Babies

1985 ◽  
Vol 2 (1) ◽  
pp. 59-64
Author(s):  
Michael Free ◽  
Margaret Beekhuis
Keyword(s):  
Young Woman ◽  
Skin Conductance ◽  
Treatment Strategy ◽  
Physiological Measures ◽  
Systematic Desensitization ◽  
Physiological Measure ◽  
One Year

A case study is presented of a young woman with an unusual phobia, a fear of babies. Barabasz's (1977) technique of systematic desensitization using psycho-physiological measures was chosen as the main treatment strategy. Difficulties arose as the client was unable to visualise scenes involving babies. Nor could she look at photographs of babies long enough for the hierarchy to be ordered using a psycho-physiological measure (skin conductance). A set of photographs was eventually used for the hierarchy, but it was ordered in terms of the length of time the client could look at the various photographs. Systematic desensitization was carried out using the set of photographs instead of imaginary scenes, together with some in vivo exposure in the latter stages of treatment. At termination the client could approach babies without discomfort. Improvement was maintained at one year follow-up.

Abstract 562: Human Carotid Atherosclerosis Plaque Progression and Vessel Material Stiffness at Follow Up Had Positive Correlation: An in vivo Vessel Stiffness MRI Follow Up Study

2017 ◽  
Vol 37 (suppl_1) ◽  
Author(s):  
Qingyu Wang ◽  
Dalin Tang ◽  
Gador Canton ◽  
Jian Guo ◽  
Xiaoya Guo ◽  
...  
Keyword(s):  
Negative Correlation ◽  
Material Properties ◽  
Stretch Ratio ◽  
Patient Specific ◽  
Plaque Progression ◽  
Material Stiffness ◽  
Variation Rate ◽  
Vessel Material

It is hypothesized that artery stiffness may be associated with plaque progression. However, in vivo vessel material stiffness follow-up data is lacking in the literature. In vivo 3D multi-contrast and Cine magnetic resonance imaging (MRI) carotid plaque data were acquired from 8 patients with follow-up (18 months) with written informed consent obtained. Cine MRI and 3D thin-layer models were used to determine parameter values of the Mooney-Rivlin models for the 81slices from 16 plaques (2 scans/patient) using our established iterative procedures. Effective Young’s Modulus (YM) values for stretch ratio [1.0,1.3] were calculated for each slice for analysis. Stress-stretch ratio curves from Mooney-Rivlin models for the 16 plaques and 81 slices are given in Fig. 1. Average YM value of the 81 slices was 411kPa. Slice YM values varied from 70 kPa (softest) to 1284 kPa (stiffest), a 1734% difference. Average slice YM values by vessel varied from 109 kPa (softest) to 922 kPa (stiffest), a 746% difference. Location-wise, the maximum slice YM variation rate within a vessel was 306% (139 kPa vs. 564 kPa). Average slice YM variation rate within a vessel for the 16 vessels was 134%. Average variation of YM values from baseline (T1) to follow up (T2) for all patients was 61.0%. The range of the variation of YM values was [-28.4%, 215%]. For progression study, YM increase (YMI=YM T2 -TM T1 ) showed negative correlation with plaque progression measured by wall thickness increase (WTI), (r= -0.6802, p=0.0634). YM T2 showed strong negative correlation with WTI (r= -0.7764, p=0.0235). Correlation between YM T1 and WTI was not significant (r= -0.4353, p= 0.2811). Conclusion In vivo carotid vessel material properties have large variations from patient to patient, along the vessel segment within a patient, and from baseline to follow up. Use of patient-specific, location specific and time-specific material properties could potentially improve the accuracy of model stress/strain calculations.

Risk Forecast of In-Stent Restenosis by CFD Method

2014 ◽  
Vol 553 ◽  
pp. 235-239
Author(s):  
Chang Yan Lin ◽  
Xiu Jian Liu ◽  
Yu Yang Liu ◽  
Chuang Ye Xu ◽  
Guang Hui Wu
Keyword(s):  
Arterial Wall ◽  
Patient Specific ◽  
Stent Restenosis ◽  
Stent Treatment ◽  
Bifurcation Lesions ◽  
Risk Forecast ◽  
One Year ◽  
Cfd Method ◽  
In Stent Restenosis

The treatment of plaques near and involving coronary bifurcations (CB) is especially challenging, considering more plaques localized these regions and higher post-interventional in-stent restenosis (ISR) risk, mainly due to hemodynamic injury provoked on the arterial wall. Therefore optimization of stenting should begin with an understanding of how disease localized to these regions and why ISR formed associated with flow patterns. We chose four patients with bifurcation lesions, two patients with ISR and two without ISR according to the follow-up computed tomography angiography (CTA). Based on patient-specific pre-interventional and virtual stented geometries from CTA images, numerical simulation indicated that the wall shear stress (WSS) in stented segments, where the ISR occurred in one year, was lower than those without ISR, however. For bifurcation lesion, the stenting segments WSS is supposed a marker to forecast the ISR risk after stent treatment.

scholarly journals What are the Risk Factors for Worse Outcomes of Meniscus Surgery in 23-39-Year-Old Patients Ligamentously Stable Knees?

2020 ◽  
Vol 8 (7_suppl6) ◽  
pp. 2325967120S0046
Author(s):  
◽  
Megan Flynn ◽  
Anthony Egger ◽  
Yuxuan Jin ◽  
Elizabeth Sosic ◽  
...  
Keyword(s):  
Risk Factors ◽  
Young Adult ◽  
Patient Reported Outcomes ◽  
Meniscal Repair ◽  
Patient Specific ◽  
Lower Baseline ◽  
Patient Reported ◽  
Grade 3 ◽  
One Year

Objectives: Meniscus tears are a common and significant source of knee dysfunction in active young adult patients, and no high-quality prospective cohort or RCTs studies exist evaluating patient-reported outcomes in patients in this age group with ligamentously stable knees. Our objective was to identify patient-reported outcomes and patient-specific risk factors from a prospective cohort with a minimum of one-year follow-up following meniscal repair or excision in patients with ligamentously stable knees. We hypothesized that both groups would have significant improvement in outcomes; patients undergoing meniscal repair would have a higher reoperation rate; and articular cartilage injuries, subsequent knee surgery, and certain demographic characteristics would be significant risk factors to inferior outcomes at one year. Methods: Between February 2015 and December 2017, ligamentously stable meniscal procedures were enrolled and prospectively followed using the outcomes management evaluation system (OME) at Cleveland Clinic. Patients aged 23-39 preoperatively completed a series of validated outcome measurements including the Knee Injury and Osteoarthritis Outcome Score for both Pain (KOOS Pain) and Quality of Life (KOOS QoL). At the time of surgery, physicians documented all intra-articular findings, treatment, and surgical techniques utilized. Patients were followed at minimum of 1-year postoperatively through the OME platform and asked to complete the same outcome instruments done at baseline as well as a question designed to evaluate the Patient Acceptable Symptom State (PASS). The incidence and details of any subsequent knee surgeries were also obtained. Multivariable regression analysis was used to identify significant predictors of outcomes. Results: A total of 371 patients aged 23-39 underwent meniscus excision or repair during the study period. One hundred ninety-four met inclusion criteria, and one-year follow-up was obtained on 72% (n = 139) of the cohort (67% male; median age 32). Both KOOS Pain and KOOS QoL improved significantly at one-year for the entire cohort. Fourteen percent of the cohort (9% on the ipsilateral knee, 5% on the contralateral knee) underwent subsequent surgery at a minimum of one-year postoperatively. The patient-specific risk factors for worse one-year outcomes included preoperative baseline mental capacity score (VR-12 MCS), lower baseline KOOS QoL score, and the intraoperative finding of any grade 3 or 4 chondral changes. Conclusion: Young adult patients with ligamentously stable knees undergoing meniscal surgery have significantly improved patient-reported outcomes regardless of excision or repair; however, 14% of patients underwent additional knee surgery at a minimum of one-year postoperatively. The risk factors for worse outcomes include lower baseline mental health score, lower baseline KOOS QoL score, and any grade 3 or 4 chondromalacia scene.

Immunological effects of in vivo βIFN-1b treatment in 10 MS patients: a one year follow-up

1998 ◽  
Vol 90 (1) ◽  
pp. 96
Author(s):  
M. Gelati ◽  
E. Corsini ◽  
A. Dufour ◽  
G. Massa ◽  
L. La Mantia ◽  
...  
Keyword(s):  
Immunological Effects ◽  
One Year

Interferon-Alpha (IFN-a) Is Able To Maintain Complete Molecular Response (CMR) In Chronic Myeloid Leukemia (CML) Patients Who Maintain Undetectable disease After Imatinib (IM) Discontinuation

Blood ◽  
2013 ◽  
Vol 122 (21) ◽  
pp. 5195-5195
Author(s):  
Angelo Michele Carella ◽  
Germana Beltrami ◽  
Chiara Ghiggi
Keyword(s):  
Myeloid Leukemia ◽  
Conflicts Of Interest ◽  
Leukemic Cells ◽  
Attractive Alternative ◽  
Molecular Response ◽  
Cytotoxic Lymphocytes ◽  
Antigenic Peptides ◽  
One Year

Abstract Cytotoxic lymphocytes (CTLs) which recognize distinct antigenic peptides on CML cells, contributed greatly to the eradication of leukemic cells after allografting. Previously, BCR-ABL specific peptides and the PR1 non-apeptide, were found to elicit a CML-specific CTL response. PR1 is a peptide derived from myeloblastin (MBN), also known as proteinase 3. MBN is abundantly expressed in azurophil granules of normal myeloid cells and is substantially overexpressed in certain immature myeloid leukemia cells where it may be important for the maintenance of a leukemic phenotype. PR1-specific CTLs (PR1-CTLs) lyses and inhibits the proliferation of CML cells but not of normal myeloid precursors. The association between the emergence of PR1-CTLs and the response to IFN-a in vivo strongly implied that IFN-a can induce remissions via induction of a CML-specific PR1-CTLs response. Therefore IFN-a, given to CML patient with undetectable disease achieved with IM, might enable its discontinuation. Ten consecutive CML patients, who were in stable CMR for at least one year after IM therapy, discontinued IM and received IFN-a. This drug was given at the dose of 3M/U/m2 weekly. The median duration of IM therapy before discontinuation was 60 (range, 31-76) months. At a median follow-up of 40 months (range, 26-58 months), five patients still have undetectable level of BCR-ABL transcript. Five patients relapsed at a median of 8 months (range, 3 – 11 months) but all except one, achieved a new CMR after reintroduction of IM. Grade 2 intolerance (muscle pain, fever) to IFN-a developed in 6/10 patients. The details of patients characteristics will be discussed during the presentation. These preliminary results demonstrate that treatment with low dose IFN-a offered to CML patients with undetectable disease is feasible and this approach may become an attractive alternative to TKI discontinuation alone. Disclosures: No relevant conflicts of interest to declare.

scholarly journals Camouflage effects following resin infiltration of postorthodontic white-spot lesions in vivo: One-year follow-up

2015 ◽  
Vol 85 (3) ◽  
pp. 374-380 ◽  
Author(s):  
Amely Eckstein ◽  
Hans-Joachim Helms ◽  
Michael Knösel
Keyword(s):  
White Spot ◽  
White Spot Lesions ◽  
Female Ratio ◽  
Significance Level ◽  
Resin Infiltration ◽  
Male Female Ratio ◽  
The Difference ◽  
One Year

ABSTRACT Objective:  To assess camouflage effects by concealment of postorthodontic white-spot lesions (WSLs) to sound adjacent enamel (SAE) achieved over 12 months with resin infiltration (Icon, DMG, Hamburg, Germany). Methods:   Twenty subjects (trial teeth nteeth = 111) who had received resin infiltration treatment of noncavitated postorthodontic WSLs were contacted for a 1-year follow-up assessment of CIE-L*a*b* colors (T12). Color and lightness (CIE-L*a*b*) data for WSLs and SAE were compared to baseline data assessed before infiltration (T0) and those assessed after 6 months (T6), using a spectrophotometer. The target parameter was the difference between the summarized color and lightness values (ΔEWSL/SAE). Intergroup (WSL, SAE) and intertime comparisons (T0 vs T6, T12) were performed using paired t-tests at a significance level of α = 5%. Results:  Nine subjects (trial teeth nteeth = 49; male/female ratio 5/4; age range 13–19 years) were available at T12. After the highly significant reduction of ΔEWSL/SAE discrepancies between T0 and T6, analysis of 12-month records revealed color and lightness discrepancy of WSL vs SAE that was significantly decreased compared with baseline, indicating an assimilation of WSL color to SAE appearance after infiltration, while an additional reduction of discrepancies between T6 and T12 was not significant. Conclusion:  As color and lightness characteristics of the Icon infiltrant as well as the esthetic camouflage effects achieved by WSL infiltration were not altered significantly or clinically relevant after 12 months, the method of resin infiltration can be recommended for an enduring esthetic improvement of postorthodontic WSL. (Angle Orthod. 2015;85:374–380.)

scholarly journals Can we obtain in vivo transmural mean hoop stress of the aortic wall without knowing patient-specific material properties and residual deformations?

2018 ◽  
Author(s):  
Minliang Liu ◽  
Liang Liang ◽  
Haofei Liu ◽  
Ming Zhang ◽  
Caitlin Martin ◽  
...  
Keyword(s):  
Material Properties ◽  
Hoop Stress ◽  
Aortic Wall ◽  
Patient Specific ◽  
Membrane Stress ◽  
Penalty Approach ◽  
Thin Walled ◽  
Specific Material ◽  
Residual Deformations

AbstractIt is well known that residual deformations/stresses alter the mechanical behavior of arteries, e.g. the pressure-diameter curves. In an effort to enable personalized analysis of the aortic wall stress, approaches have been developed to incorporate experimentally-derived residual deformations into in vivo loaded geometries in finite element simulations using thick-walled models. Solid elements are typically used to account for “bending-like” residual deformations. Yet, the difficulty in obtaining patient-specific residual deformations and material properties has become one of the biggest challenges of these thick-walled models. In thin-walled models, fortunately, static determinacy offers an appealing prospect that allows for the calculation of the thin-walled membrane stress without patient-specific material properties. The membrane stress can be computed using forward analysis by enforcing an extremely stiff material property as penalty treatment, which is referred to as the forward penalty approach. However, thin-walled membrane elements, which have zero bending stiffness, are incompatible with the residual deformations, and therefore, it is often stated as a limitation of thin-walled models. In this paper, by comparing the predicted stresses from thin-walled models and thick-walled models, we demonstrate that the transmural mean hoop stress is the same for the two models and can be readily obtained from in vivo clinical images without knowing the patient-specific material properties and residual deformations. Computation of patient-specific mean hoop stress can be greatly simplified by using membrane model and the forward penalty approach, which may be clinically valuable.

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