In Vivo Analysis of Heterogeneous Brain Deformation Computations for Model-Updated Image Guidance

Neurosurgical image-guidance has historically relied on the registration of the patient and preoperative imaging series with surgical instruments in the operating room (OR) coordinate space. Recent studies measuring intraoperative tissue motion have suggested that deformation-induced misregistration from surgical loading is a serious concern with such systems. In an effort to improve registration fidelity during surgery, we are pursuing an approach which uses a predictive computational model in conjunction with data available in the OR to update the high resolution preoperative image series. In previous work, we have developed an in vivo experimental system in the porcine brain which has been used to investigate a homogeneous finite element rendering of consolidation theory as a tissue deformation model. In this paper, our computational approach has been extended to include heterogeneous tissue property distributions determined from an image-to-grid segmentation scheme. Results produced under two different loading conditions show that heterogeneity in the stiffness properties and interstitial pressure gradients varied over a range of physiologically reasonable values account for 1-3% and 5-8% of the predicted tissue motion, respectively, while homogeneous linear elasticity is responsible for 60-70% of the surgically-induced motion that has been recoverable with our model-based approach.     

Intraoperative Biomechanical Registration of the Liver: Does the Heterogeneity of the Liver Matter?

Background: Preoperative images such as computed tomography scans or magnetic resonance imaging contain lots of valuable information that are not easily available for surgeons during an operation. To help the clinicians better target the structures of interest during an intervention, many registration methods that align preoperative images onto the intraoperative view of the organs have been developed. For important organ deformation, biomechanically-based registration has proven to be a method of choice.Method: Using an existing biomechanically-based registration algorithm for laparoscopic liver surgery we investigate in this paper the influence of the heterogeneity of the liver on the registration result.Results: No statistical difference in the results was found between the registration performed with the homogeneous model and the one carried out with the heterogeneous model.Conclusion: As the use of an heterogeneous model does not improve significantly the registration result and increase the computation time we recommend to perform the type of registration task described in the paper with a simplified homogeneous model.     

胸外科手术术后神经病理性疼痛的发生情况及相关因素分析

目的:探讨胸外科手术术后神经病理性疼痛的发生情况及相关危险因素。方法:回顾性分析2015年至2016年就诊于我院行胸外科手术的患者的临床资料,包括患者的年龄、性别、吸烟史、BMI、术前是否使用催眠药物、术前诊断、手术侧别、手术方式、是否为微创、硬膜外自控镇痛泵使用情况、术中失血量、手术持续时间、引流管引流时间及是否发生神经病理性疼痛,对比分析是否发生神经病理性疼痛患者的临床资料,对有差异的临床资料进行多因素Logistic回归分析探讨发生神经病理性疼痛的危险因素。结果:共有123例患者纳入研究,33例(26.8%)患者的患者术后出现神经病理性疼痛,6例(4.9%)患者在术后一年仍有持续性神经性病理疼痛,术后出现神经病理性疼痛的平均时间为术后第7天,平均持续时间为75天,发生神经病理性疼痛的患者吸烟比例(81.8%)、术前使用催眠药比例(57.6%)、开胸手术比例(81.8%)、术中失血量(185 mL)、手术时间(196分钟)、术后引流时间(2.5天)均高于没有发生神经病理性疼痛的患者。多因素分析显示术前使用催眠药(OR=2.322,P<0.001)、手术时间延长(OR=3.703,P<0.001)和术后引流时间延长(OR=2.675,P=0.002)均是神经病理性疼痛发生的危险因素,电视辅助胸腔镜手术方式是保护性因素(OR=0.453,P=0.002)。结论:术前使用催眠药物、延长的手术时间及术后引流时间增加了神经病理性疼痛发生的风险,电视辅助胸腔镜技术可减少其发生率。     

Overview of Molecular Biomarkers for Enhancing the Management of Cytologically Indeterminate Thyroid Nodules and Thyroid Cancer

ObjectiveTo provide information on molecular bio markers that can help assess cytologically indeterminate thyroid nodules.MethodsPublished studies on immunohistologic, somatic mutation, gene expression classifier, microRNA, and thyrotropin receptor messenger RNA biomarkers are reviewed, and commercially available molecular test pan els are described.ResultsThyroid nodules are common, and clinical guidelines delineate an algorithmic approach including serum thyroid-stimulating hormone measurement, diagnostic ultrasound examination, and, when appropriate, fine-needle aspiration (FNA) biopsy for determination of a benign versus malignant status. In clinical practice, approximately 20% of FNA-derived cytology reports are classified as “indeterminate” or follicular nodules that do not fulfill either benign or malignant criteria. In this set ting, the actual risk for malignancy of a cytologically indeterminate nodule ranges from approximately 15% to 34%. Research describing molecular biomarkers from thyroid cancer tissue has been applied to FNA-derived thyroid nodule material. There is also a serum molecular marker that has been reported with goals similar to those for the FNA-derived molecular markers: to enhance the preoperative diagnosis of thyroid cancer and reduce the large number of patients who have a diagnostic surgical procedure for benign thyroid nodules.ConclusionProgress toward the foregoing goals has been made and continues to evolve with the recent appearance of molecular biomarker tests that can be selectively applied for further assessment of cytologically indeterminate thyroid nodules. (Endocr Pract. 2012;18:611-615)     

Perioperative Myocardial Injury after Adult Heart Transplant: Determinants and Prognostic Value

MethodsData on 362 consecutive recipients (mean age: 47.8±13.7, 20.2% female, 18.2% diabetics, 22.1% with previous cardiac operations, 27.6% hospitalized, 84.9±29.4 ml/min preoperative glomerular filtration rate) were analyzed using multivariable logistic regression modeling. Target outcomes were determinants of troponin release, early graft failure (EGF), acute kidney injury (AKI) and operative death.ResultsMean cTnI release measured 24 hours after transplant was 10.9±11.6 μg/L. Overall hospital mortality was 10.8%, EGF 10.5%, and AKI was 12.2%. cTnI release>10 μg/L proved an independent predictor of EGF (OR 2.2; 95% CI, 1.06–4.6) and AKI (OR 1.031; 95% CI, 1.001-1.064). EGF, in turn, proved a determinant of hospital mortality. Risk factors for cTnI>10 μg/L release were: status 2B (OR 0.35; 95% CI, 0.18-0.69, protective), duration of the ischemic period (OR 1.006; 95% CI, 1.001-1.011), previous cardiac operation (OR 2.9; 95% CI, 1.67-5.0), and left ventricular hypertrophy (OR 3.3; 95% CI, 1.9-5.6).ConclusionsMyocardial enzyme leakage clearly emerged as an epiphenomenon of more complicated clinical course. The complex interplay between surgical procedure features, graft characteristics and recipient end-organ function highlights cTnI release as a risk marker of graft failure and acute kidney injury. The search for optimal myocardial preservation is still an issue.     

Optimization of Minimally Invasive Radio-Guided Parathyroidectomy: The Importance of Neck Ultrasonography and Intraoperative Parathyroid Hormone Assay

ObjectiveTo determine whether close collaboration between a neck ultrasound–certified endocrinologist and a skilled endocrine surgeon can optimize minimally invasive radio-guided parathyroidectomy (MIRP) surgical outcomes.MethodsOutcome data were collected on patients with primary hyperparathyroidism whom we intended to treat with MIRP at the induction of anesthesia between October 1, 2005, and December 31, 2007. Patients underwent preoperative gamma camera sestamibi scanning (GCSS), intraoperative gamma probe sestamibi scanning (IOSS), and preoperative neck ultrasonography. Intraoperative parathyroid hormone (PTH) monitoring was performed. Postoperative surgical success was defined as a serum calcium concentration between 8.0 and 10.4 mg/dL within 4 weeks of surgery.ResultsDuring the study period, MIRP was planned for 46 patients. Of the 46 patients, 39 had preoperative neck ultrasonography; 7 underwent evaluation by an endocrinologist or internist who was not ultrasound certified and they therefore did not undergo preoperative ultrasonography. IOSS correctly identified 1 adenomatous gland in 38 of 46 patients (83%), while GCSS correctly localized 1 adenomatous gland in 30 of 46 patients (65%). In 11 GCSS–negative patients, IOSS identified the abnormal gland in 7 (64%), while ultrasonography identified the abnormal gland in 8 (73%). The surgical approach was converted to traditional parathyroidectomy in 3 patients. Every patient exhibited at least a 51% drop in intraoperative PTH levels with resection of the final adenoma; average decrement for the entire group was 79 ± 8% from the highest baseline level. Forty-five patients (98%) demonstrated sustained normalization of serum calcium within several days of surgery.ConclusionA collaborative endocrinology and surgical endocrine oncology practice arrangement, emphasizing careful preoperative physician-supervised neck ultrasonography and the use of intraoperative PTH measurement, optimizes MIRP outcomes. (Endocr Pract. 2008;14: 856-862)     

Registration and functional analysis of CT dynamic image sequences for the follow-up of patients with hepatic tumors undergoing antiangiogenic therapy

ObjectiveA new approach for evaluating tumor response to antiangiogenic treatment using dynamic contrast-enhanced perfusion computed tomography (CT) was provided.Patients and methodsFive patients, with hepatic tumors, were examined before and a few weeks after therapy. Following injection of a contrast agent, dynamic image acquisitions were obtained during two minutes, with eight axial sections by volume. To analyze these functional data, we proposed an image processing pipeline. We first applied a rigid registration, based on a blockmatching method, to correct for respiratory motion. We then calculated parametric image volumes, using adapted reference kinetics. These image volumes allowed us to differentiate between the various contrast enhancement kinetics (arterial/venous, healthy/pathological tissues), following the injection of contrast agent.ResultsThe registration was validated qualitatively (by visual inspection of registered image volumes) and quantitatively (using criteria based on the estimation of a respiratory motion component). Parametric image volumes allowed us to differentiate healthy tissues from tumor tissues, and to display necrotic regions, which occurred in four patients, after therapy.DiscussionThe proposed approach allows us to compensate for respiratory motion in a region localized around the tumor and could be further extended by a nonrigid registration.ConclusionThe robust computation of parametric image volumes enables a local and precise display of the tumor response to an antiangiogenic therapy.     

Preoperative testing before low-risk surgical procedures

Background:There is concern about increasing utilization of low-value health care services, including preoperative testing for low-risk surgical procedures. We investigated temporal trends, explanatory factors, and institutional and regional variation in the utilization of testing before low-risk procedures.Methods:For this retrospective cohort study, we accessed linked population-based administrative databases from Ontario, Canada. A cohort of 1 546 223 patients 18 years or older underwent a total of 2 224 070 low-risk procedures, including endoscopy and ophthalmologic surgery, from Apr. 1, 2008, to Mar. 31, 2013, at 137 institutions in 14 health regions. We used hierarchical logistic regression models to assess patient- and institution-level factors associated with electrocardiography (ECG), transthoracic echocardiography, cardiac stress test or chest radiography within 60 days before the procedure.Results:Endoscopy, ophthalmologic surgery and other low-risk procedures accounted for 40.1%, 34.2% and 25.7% of procedures, respectively. ECG and chest radiography were conducted before 31.0% (95% confidence interval [CI] 30.9%–31.1%) and 10.8% (95% CI 10.8%–10.8%) of procedures, respectively, whereas the rates of preoperative echocardiography and stress testing were 2.9% (95% CI 2.9%–2.9%) and 2.1% (95% CI 2.1%–2.1%), respectively. Significant variation was present across institutions, with the frequency of preoperative ECG ranging from 3.4% to 88.8%. Receipt of preoperative ECG and radiography were associated with older age (among patients 66–75 years of age, for ECG, adjusted odds ratio [OR] 18.3, 95% CI 17.6–19.0; for radiography, adjusted OR 2.9, 95% CI 2.8–3.0), preoperative anesthesia consultation (for ECG, adjusted OR 8.7, 95% CI 8.5–8.8; for radiography, adjusted OR 2.2, 95% CI 2.1–2.2) and preoperative medical consultation (for ECG, adjusted OR 6.8, 95% CI 6.7–6.9; for radiography, adjusted OR 3.6, 95% CI 3.5–3.6). The median ORs for receipt of preoperative ECG and radiography were 2.3 and 1.6, respectively.Interpretation:Despite guideline recommendations to limit testing before low-risk surgical procedures, preoperative ECG and chest radiography were performed frequently. Significant variation across institutions remained after adjustment for patient- and institution-level factors.In response to concerns about increasing utilization of low-value health care services, the American Board of Internal Medicine Foundation launched the Choosing Wisely campaign in the United States in 2012.¹ The goal of the campaign is to encourage conversations between physicians and patients about low-value care by defining “top 5” lists of tests, treatments and procedures that may be unnecessary or unsupported by evidence.¹ Subsequent Choosing Wisely campaigns have followed in other countries, including Canada starting in April 2014.^2,3 Of interest for health policy-makers, payers and clinicians are current utilization rates for the procedures mentioned in these recommendations. Establishing baseline rates permits an understanding of the extent of the problem of low-value care, which in turn allows monitoring of the effect of initiatives such as Choosing Wisely on utilization rates over time.One Choosing Wisely item included by many specialty societies is the recommendation to avoid routinely performing preoperative testing (including chest radiography, echocardiography and cardiac stress tests) for patients undergoing low-risk surgery.^4–6 This recommendation was previously included in the 2007 American College of Cardiology/American Heart Association guidelines on perioperative cardiovascular evaluation for noncardiac surgery⁷ and was reconfirmed in a recent update.⁸ Avoiding preoperative investigations in this setting is supported by evidence that routine testing in patients undergoing low-risk surgery does not improve outcomes or change management and may lead to further unnecessary downstream testing, cancellation of surgery, and increases in patient anxiety and cost.^7,9–12 To date, neither the rate of preoperative testing across a large and diverse jurisdiction nor the degree of variation at regional and institutional levels, where data may be “actionable,” is well understood.The objectives of this study were to determine utilization rates of preoperative tests before hospital-based low-risk surgical procedures at the jurisdictional, regional and institutional level. In addition, we aimed to evaluate temporal trends of preoperative testing over a 5-year period. We hypothesized that there would be significant regional and institutional variation in preoperative cardiac testing before low-risk surgery and that patients with prior cardiac comorbidities would have a higher rate of preoperative testing than those without such comorbidities.     

Impact of motion induced artifacts on automatic registration of lung tumors in Tomotherapy

PurposeTomotherapy MV-CT acquisitions of lung tumors lead to artifacts due to breathing-related motion. This could preclude the reliability of tumor based positioning. We investigate the effect of these artifacts on automatic registration and determine conditions under which correct positioning can be achieved.Materials and methodsMV-CT and 4D-CT scans of a dynamic thorax phantom were acquired with various motion amplitudes, directions, and periods. For each acquisition, the average kV-CT image was reconstructed from the 4D-CT data and rigidly registered with the corresponding MV-CT scan in a region of interest. Different kV–MV registration strategies have been assessed.ResultsAll tested registration methods led to acceptable registration errors (within 1.3 ± 1.2 mm) for motion periods of 3 and 6 s, regardless of the motion amplitude, direction, and phase difference. However, a motion period of 5 s, equal to half the Tomotherapy gantry period, induced asymmetric artifacts within MV-CT and significantly degraded the registration accuracy.ConclusionsAs long as the breathing period differs from 5 s, positioning based on averaged images of the tumor provides information about its daily baseline shift, and might therefore contribute to reducing margins, regardless of the registration method.     

Comparison of the Accuracy of Voxel Based Registration and Surface Based Registration for 3D Assessment of Surgical Change following Orthognathic Surgery

Purpose

Superimposition of two dimensional preoperative and postoperative facial images, including radiographs and photographs, are used to evaluate the surgical changes after orthognathic surgery. Recently, three dimensional (3D) imaging has been introduced allowing more accurate analysis of surgical changes. Surface based registration and voxel based registration are commonly used methods for 3D superimposition. The aim of this study was to evaluate and compare the accuracy of the two methods.

Materials and methods

Pre-operative and 6 months post-operative cone beam CT scan (CBCT) images of 31 patients were randomly selected from the orthognathic patient database at the Dental Hospital and School, University of Glasgow, UK. Voxel based registration was performed on the DICOM images (Digital Imaging Communication in Medicine) using Maxilim software (Medicim-Medical Image Computing, Belgium). Surface based registration was performed on the soft and hard tissue 3D models using VRMesh (VirtualGrid, Bellevue City, WA). The accuracy of the superimposition was evaluated by measuring the mean value of the absolute distance between the two 3D image surfaces. The results were statistically analysed using a paired Student t-test, ANOVA with post-hoc Duncan test, a one sample t-test and Pearson correlation coefficient test.

Results

The results showed no significant statistical difference between the two superimposition methods (p<0.05). However surface based registration showed a high variability in the mean distances between the corresponding surfaces compared to voxel based registration, especially for soft tissue. Within each method there was a significant difference between superimposition of the soft and hard tissue models.

Conclusions

There were no significant statistical differences between the two registration methods and it was unlikely to have any clinical significance. Voxel based registration was associated with less variability. Registering on the soft tissue in isolation from the hard tissue may not be a true reflection of the surgical change.     

Preoperative prediction of microvascular invasion in non-metastatic hepatocellular carcinoma based on nomogram analysis

PurposeThe presence of microvascular invasion (MVI) is an unfavorable prognostic factor for hepatocellular carcinoma (HCC). This study aimed to construct a nomogram-based preoperative prediction model of MVI, thereby assisting to preoperatively select proper surgical procedures.MethodsA total of 714 non-metastatic HCC patients undergoing radical hepatectomy were retrospectively selected from Zhongshan Hospital between 2010 and 2018, followed by random assignment into training (N = 520) and validation cohorts (N = 194). Nomogram-based prediction model for MVI risk was constructed by incorporating independent risk factors of MVI presence identified from multivariate backward logistic regression analysis in the training cohort. The performance of nomogram was evaluated by calibration curve and ROC curve. Finally, decision curve analysis (DCA) was used to determine the clinical utility of the nomogram.ResultsIn total, 503 (70.4%) patients presented MVI. Multivariate analysis in the training cohort revealed that age (OR: 0.98), alpha-fetoprotein (≥400 ng/mL) (OR: 2.34), tumor size (>5 cm) (OR: 3.15), cirrhosis (OR: 2.03) and γ-glutamyl transpeptidase (OR: 1.61) were significantly associated with MVI presence. The incorporation of five risk factors into a nomogram-based preoperative estimation of MVI risk demonstrated satisfactory discriminative capacity, with C-index of 0.702 and 0.690 in training and validation cohorts, respectively. Calibration curve showed good agreement between actual and predicted MVI risks. Finally, DCA revealed the clinical utility of the nomogram.ConclusionThe nomogram showed a satisfactory discriminative capacity of MVI risk in HCC patients, and could be used to preoperatively estimate MVI risk, thereby establishing more rational therapeutic strategies.     

外伤性肝破裂患者腹腔镜下修补术后发生焦虑抑郁的危险因素分析

目的:探讨外伤性肝破裂患者腹腔镜下修补术后发生焦虑抑郁的危险因素。方法:应用前瞻性研究方法,采用一般资料问卷调查表、焦虑自评量表、抑郁自评量表对本院收治的150例外伤性肝破裂患者进行心理测评,分析术后焦虑和抑郁状态的发生情况。根据术后的状态分为三组,术后存在焦虑的患者为焦虑状态组(n=53),存在抑郁状态的患者为抑郁状态组(n=57),术后无焦虑抑郁状态的为对照组(n=40)。对焦虑和抑郁形成的危险因素进行多因素Logistic回归分析。结果:焦虑状态组(n=53)、抑郁状态组(n=57)及对照组(n=40)平均年龄、平均受教育年限比较差异无统计学意义(P0.05);而经济月收入、居住地、负面情绪、术前并发症、医保报销、家庭和睦、术前住院时间差异具有统计学意义(P0.05)。手术过程的手术时间、外循环时间、主动脉阻断时间、外循环百分比比较差异均无统计学意义(P0.05);而麻醉苏醒时间、ICU停留时间差异具有统计学意义(P0.05)。术后担忧的问题及需求(治疗需求和心理需求)比较差异均具有统计学意义(P0.05)。Logistic回归分析结果显示文化程度(OR=1.254)、负面情绪(OR=1.245)、家庭收入(OR=2.324)、手术疗效(OR=2.258)均为焦虑发生的危险因素;文化程度(OR=4.230)、负面情绪(OR=1.254)、家庭收入(OR=1.236)、手术疗效(OR=2.120)均为抑郁发生的危险因素。结论:外伤性肝破裂患者腹腔镜下修补术后焦虑抑郁的形成可能与患者的文化高低、负面情绪、手术疗效、家庭收入和术前并发症有关。     

Constitutive modelling of brain tissue: Experiment and theory

Recent developments in computer-integrated and robot-aided surgery—in particular, the emergence of automatic surgical tools and robots—as well as advances in virtual reality techniques, call for closer examination of the mechanical properties of very soft tissues (such as brain, liver, kidney, etc.). The ultimate goal of our research into the biomechanics of these tissues is the development of corresponding, realistic mathematical models. This paper contains experimental results of in vitro, uniaxial, unconfined compression of swine brain tissue and discusses a single-phase, non-linear, viscoelastic tissue model. The experimental results obtained for three loading velocities, ranging over five orders of magnitude, are presented. The applied strain rates have been much lower than those applied in previous studies, focused on injury modelling. The stress-strain curves are concave upward for all compression rates containing no linear portion from which a meaningful elastic modulus might be determined. The tissue response stiffened as the loading speed increased, indicating a strong stress-strain rate dependence. The use of the single-phase model is recommended for applications in registration, surgical operation planning and training systems as well as a control system of an image-guided surgical robot. The material constants for the brain tissue are evaluated. Agreement between the proposed theoretical model and experiment is good for compression levels reaching 30% and for loading velocities varying over five orders of magnitude.     

Similar Outcomes Achieved Between Anterior and Posterior Approach Total Hip Arthroplasty Using Dual Mobility Implants

BackgroundDual mobility (DM) bearings for total hip arthroplasty (THA) have been proposed to reduce the risk of instability in high-risk patients; however, their utility in primary THA remains relatively unexplored. No previous reports have described whether surgical approach influences outcomes associated with DM implant systems. This study aims to compare patient reported outcomes and post-operative groin pain between patients undergoing anterior approach versus posterior approach following primary THA with DM implants.MethodsWe retrospectively reviewed all patients who underwent primary THA and received a DM implant between 2011-2021. Patients were stratified into two cohorts based on surgical approach (anterior vs. posterior approach). Primary outcomes included the presence of substantial postoperative groin pain as well as readmission and revision rates. Demographic differences were assessed using chi-square and independent sample t-tests. Outcomes were compared using multilinear and logistic regressions.ResultsOf the 495 patients identified, 55 (11%) underwent THA via the anterior approach and 440 (89%) via the posterior approach. Surgical time (100.24 vs. 109.42 minutes, p=0.070), length of stay (2.19vs.2.67 days,p=0.072), discharge disposition (p=0.151), and significant postoperative groin pain (1.8%vs.0.7%,p=0.966) did not statistically differ between the cohorts. 90-day readmission (9.1%vs.7.7%,p=0.823) and revision rate (0.0%vs.3.0%,p=0.993) did not significantly differ as well. Specifically, readmission (p=0.993) and revision (p=0.998) for instability did not significantly differ between the cohorts. We found no statistical difference in HOOS, JR (p=0.425), VR-12 PCS (p=0.718), and VR-12 MCS (p=0.257) delta score improvement from preoperative to 1-year follow-up between the two groups.ConclusionComparable outcomes following implantation of DM constructs may be achievable irrespective of the surgical approach employed. The incidence of iliopsoas injections for groin pain did not significantly differ between anterior and posterior approaches. Future investigation is needed to determine whether surgical approach influences long-term outcomes in patients receiving DM implants. Level of Evidence: III     

Preoperative and Postoperative Evaluation of Thyroid Disease in Patients Undergoing Surgical Treatment of Primary Hyperparathyroidism

ObjectiveTo evaluate the occurrence of thyroid disease in patients undergoing parathyroidectomy for primary hyperparathyroidism.MethodsIn this case series, records of all patients with a diagnosis of primary hyperparathyroidism who underwent parathyroidectomy between January 2005 and December 2008 in our clinic were analyzed retrospectively. Preoperatively, all patients were evaluated with ultrasonography and parathyroid scintigraphy; when needed, thyroid scintigraphy and ultrasound-guided fine-needle aspiration biopsy (FNAB) were used. All patients underwent standard neck exploration. Postoperative histopathologic findings of thyroid tissue were classified as nodular/ multinodular hyperplasia, Hashimoto thyroiditis, papillary thyroid carcinoma, or normal.ResultsFifty-one women and 9 men were included. In the 60 patients, preoperative ultrasonography revealed thyroiditis (without nodules) in 13 (22%), a solitary nodule in 9 (15%) (coexistent with thyroiditis in 7 patients), multinodular goiter in 24 (40%) (coexistent with thyroiditis in 5 patients), and normal findings in 14 (23%). Rates of thyroiditis and nodular goiter were 42% and 55%, respectively. Collectively, prevalence of thyroid disease was 77%. Total thyroidectomy was performed in 27 patients, and hemithyroidectomy was performed in 15 patients. Indications for total thyroidectomy were nondiagnostic or suspicious FNAB results in 5 patients, hyperthyroidism in 4 patients, ultrasonography findings in 11 patients, and intraoperatively recognized suspicious nodularity in 7 patients. Postoperatively, thyroid carcinoma was diagnosed in 9 patients (15%).ConclusionsThyroid disease, particularly thyroid carcinoma, is common in patients with primary hyperparathyroidism. This association should be considered when selecting the surgical procedure. Intraoperative evaluation of the thyroid is as important as preoperative evaluation with ultrasonography and FNAB in patients with thyroid disease and primary hyperparathyroidism. (Endocr Pract. 2010;16:7-13)     

Identification of emergent motion compartments in the amniote embryo

Abstract

The tissue scale deformations (≥1mm) required to form an amniote embryo are poorly understood. Here, we studied ～400 μm-sized explant units from gastrulating quail embryos. The explants deformed in a reproducible manner when grown using a novel vitelline membrane-based culture method. Time-lapse recordings of latent embryonic motion patterns were analyzed after disk-shaped tissue explants were excised from three specific regions near the primitive streak: 1) anterolateral epiblast, 2) posterolateral epiblast, and 3) the avian organizer (Hensen's node). The explants were cultured for 8 hours—an interval equivalent to gastrulation. Both the anterolateral and the posterolateral epiblastic explants engaged in concentric radial/centrifugal tissue expansion. In sharp contrast, Hensen's node explants displayed Cartesian-like, elongated, bipolar deformations—a pattern reminiscent of axis elongation. Time-lapse analysis of explant tissue motion patterns indicated that both cellular motility and extracellular matrix fiber (tissue) remodeling take place during the observed morphogenetic deformations. As expected, treatment of tissue explants with a selective Rho-Kinase (p160ROCK) signaling inhibitor, Y27632, completely arrested all morphogenetic movements. Microsurgical experiments revealed that lateral epiblastic tissue was dispensable for the generation of an elongated midline axis— provided that an intact organizer (node) is present. Our computational analyses suggest the possibility of delineating tissue-scale morphogenetic movements at anatomically discrete locations in the embryo. Further, tissue deformation patterns, as well as the mechanical state of the tissue, require normal actomyosin function. We conclude that amniote embryos contain tissue-scale, regionalized morphogenetic motion generators, which can be assessed using our novel computational time-lapse imaging approach. These data and future studies—using explants excised from overlapping anatomical positions—will contribute to understanding the emergent tissue flow that shapes the amniote embryo.     

Current Management of Surgical Oncologic Emergencies

ObjectivesFor some oncologic emergencies, surgical interventions are necessary for dissolution or temporary relieve. In the absence of guidelines, the most optimal method for decision making would be in a multidisciplinary cancer conference (MCC). In an acute setting, the opportunity for multidisciplinary discussion is often not available. In this study, the management and short term outcome of patients after surgical oncologic emergency consultation was analyzed.MethodA prospective registration and follow up of adult patients with surgical oncologic emergencies between 01-11-2013 and 30-04-2014. The follow up period was 30 days.ResultsIn total, 207 patients with surgical oncologic emergencies were included. Postoperative wound infections, malignant obstruction, and clinical deterioration due to progressive disease were the most frequent conditions for surgical oncologic emergency consultation. During the follow up period, 40% of patients underwent surgery. The median number of involved medical specialties was two. Only 30% of all patients were discussed in a MCC within 30 days after emergency consultation, and only 41% of the patients who underwent surgery were discussed in a MCC. For 79% of these patients, the surgical procedure was performed before the MCC. Mortality within 30 days was 13%.ConclusionIn most cases, surgery occurred without discussing the patient in a MCC, regardless of the fact that multiple medical specialties were involved in the treatment process. There is a need for prognostic aids and acute oncology pathways with structural multidisciplinary management. These will provide in faster institution of the most appropriate personalized cancer care, and prevent unnecessary investigations or invasive therapy.     

Rapid Diagnosis of Lung Tumors,a Feasability Study Using Maldi-Tof Mass Spectrometry

ObjectiveDespite recent advances in imaging and core or endoscopic biopsies, a percentage of patients have a major lung resection without diagnosis. We aimed to assess the feasibility of a rapid tissue preparation/analysis to discriminate cancerous from non-cancerous lung tissue.MethodsFresh sample preparations were analyzed with the Microflex LT^TM MALDI-TOF analyzer. Each main reference spectra (MSP) was consecutively included in a database. After definitive pathological diagnosis, each MSP was labeled as either cancerous or non-cancerous (normal, inflammatory, infectious nodules). A strategy was constructed based on the number of concordant responses of a mass spectrometry scoring algorithm. A 3-step evaluation included an internal and blind validation of a preliminary database (n = 182 reference spectra from the 100 first patients), followed by validation on a whole cohort database (n = 300 reference spectra from 159 patients). Diagnostic performance indicators were calculated.Results127 cancerous and 173 non-cancerous samples (144 peripheral biopsies and 29 inflammatory or infectious lesions) were processed within 30 minutes after biopsy sampling. At the most discriminatory level, the samples were correctly classified with a sensitivity, specificity and global accuracy of 92.1%, 97.1% and 95%, respectively.ConclusionsThe feasibility of rapid MALDI-TOF analysis, coupled with a very simple lung preparation procedure, appears promising and should be tested in several surgical settings where rapid on-site evaluation of abnormal tissue is required. In the operating room, it appears promising in case of tumors with an uncertain preoperative diagnosis and should be tested as a complementary approach to frozen-biopsy analysis.     

Return of Scapulohumeral Rhythm in Patients After Reverse Shoulder Arthroplasty: A Midterm Stereoradiographic Imaging Analysis

BackgroundReverse shoulder arthroplasty (RSA) is associated with high rates of midterm complications including scapular notching, implant wear, and mechanical impingement. Scapulo-humeral rhythm (SHR), described by Codman in the 1920’s, is defined as the ratio of glenohumeral motion to scapulothoracic motion. SHR is used as an indicator of shoulder dysfunction, as alterations in SHR can have profound implications on shoulder biomechanics. The determination of SHR can be hindered by soft-tissue motion artifacts and high radiation burdens associated with traditional surface marker or fluoroscopic analysis. EOS low dose stereoradiographic imaging analysis utilizing 3D model construction from a 2D X-ray series may offer an alternative modality for characterizing SHR following RSA.MethodsPatients (n=10) underwent an EOS imaging analysis to determine SHR at six and twelve months post-RSA. Leveraging 3D models of the implants, 2D/3D image registration methods were used to calculate relative glenohumeral and scapulothoracic positioning at 60, 90 and 120° of shoulder elevation. Subject-specific SHR curves were assessed and midterm changes in post-RSA SHR associated with follow-up time and motion phase were evaluated. Pearson correlations assessed associations between patient-specific factors and post-RSA SHR.ResultsMean post-RSA SHR was 0.81:1 across subjects during the entire midterm postoperative period. As a cohort, post-RSA SHR was more variable for 60-90° of shoulder motion. SHR for 90-120° of motion decreased (0.43:1) at twelve months post-RSA. Post-RSA SHR could be categorized using three relative motion curve patterns, and was not strongly associated with demographic factors such as BMI. 50% of subjects demonstrated a different SHR relative motion curve shape at twelve months post-RSA, and SHR during the 90120° of motion was found to generally decrease at twelve months.ConclusionMidterm post-RSA SHR was successfully evaluated using EOS technology, revealing lower SHR values (i.e., greater scapulothoracic motion) compared to normal values reported in the literature. SHR continued to change for some subjects during the midterm post-RSA period, with the greatest change during 90-120° of shoulder motion. Study findings suggest that future post RSA rehabilitation efforts to address elevated scapulothoracic motion may benefit from being patient-specific in nature and targeting scapular stabilization during 90-120° of shoulder motion. Level of Evidence: IV     

Pancreatic Cancer Surgical Resection Margins: Molecular Assessment by Mass Spectrometry Imaging

BackgroundSurgical resection with microscopically negative margins remains the main curative option for pancreatic cancer; however, in practice intraoperative delineation of resection margins is challenging. Ambient mass spectrometry imaging has emerged as a powerful technique for chemical imaging and real-time diagnosis of tissue samples. We applied an approach combining desorption electrospray ionization mass spectrometry imaging (DESI-MSI) with the least absolute shrinkage and selection operator (Lasso) statistical method to diagnose pancreatic tissue sections and prospectively evaluate surgical resection margins from pancreatic cancer surgery.ConclusionsOur findings provide evidence that the molecular information obtained by DESI-MSI/Lasso from pancreatic tissue samples has the potential to transform the evaluation of surgical specimens. With further development, we believe the described methodology could be routinely used for intraoperative surgical margin assessment of pancreatic cancer.