ELASTOGRAPHIC EVALUATION OF NATURALLY OCCURING TENDON AND LIGAMENT INJURIES OF THE EQUINE DISTAL LIMB.

Compression elastography is an ultrasonographic technique that estimates tissue strain and may have utility in diagnosing and monitoring soft tissue injuries in the equine athlete. Recently, elastography has been proven to be a feasible and repeatable imaging modality for evaluating normal tendons and ligaments of the equine distal forelimb. The purposes of this prospective study were to investigate the ability of elastography to detect spontaneously occurring lesions of equine tendons and ligaments diagnosed with magnetic resonance imaging (MRI) and gray-scale ultrasound (US) and to characterize the differences in the elastographic appearance of acute vs. chronic injuries. Fifty seven horses with a total of 65 lesions were evaluated. Images were assessed quantitatively and qualitatively. Acute lesions were found to be significantly softer (P < 0.0001) than chronic lesions (P < 0.0001) and the stiffness of lesions increased with progression of healing (P = 0.0138). A negative correlation between lesion hypoechogenicity and softness was appreciated with more hypoechoic lesions appearing softer (P = 0.0087) and more hyperechoic regions harder (P = 0.0002). A similar finding occurred with increased signal intensity on short tau inversion recovery (STIR) and proton density (PD) MRI sequences correlating with increased softness on elastography (P = 0.0164). Using US and MRI as references, commonly encountered soft tissue injuries of the equine distal limb could be detected with elastography. However, elastography was limited for detecting small, proximal injuries of the hindlimb proximal suspensory ligament. Elastographic evaluation of equine tendons and ligaments may allow better characterization of lesion chronicity and severity, and sequential examinations may optimize lesion management, rehabilitation, and return to training.

Teaching Thoracic Surgery in a Low-Resource Setting:: Creation of a Simulation Curriculum in Rwanda.

Surgical education and global health partnerships have evolved over the years. There is growing recognition of the importance of in-country training of surgeons and surgeon specialists in low-resource settings to support the local health care system. There are numerous ways in which high-income partners can support local training programs. The Human Resources for Health program was initiated in 2012 to advance in-country training of health care professionals in Rwanda. As there was a limited in-country operative experience for teaching general thoracic surgery, simulation models were developed, influenced by a prior course developed for American cardiothoracic trainees. Local Rwandan faculty were engaged. Adaptations from the American version included constructing models from inexpensive materials to make the simulation more feasible in the Rwanda setting.

Creation, Implementation, and Assessment of a General Thoracic Surgery Simulation Course in Rwanda.

BACKGROUND: The primary objective was to provide proof of concept of conducting thoracic surgical simulation in a low-middle income country. Secondary objectives were to accelerate general thoracic surgery skills acquisition by general surgery residents and sustain simulation surgery teaching through a website, simulation models, and teaching of local faculty. METHODS: Five training models were created for use in a low-middle income country setting and implemented during on-site courses with Rwandan general surgery residents. A website was created as a supplement to the on-site teaching. All participants completed a course knowledge assessment before and after the simulation and feedback/confidence surveys. Descriptive and univariate analyses were performed on participants' responses. RESULTS: Twenty-three participants completed the simulation course. Eight (35%) had previous training with the course models. All training levels were represented. Participants reported higher rates of meaningful confidence, defined as moderate to complete on a Likert scale, for all simulated thoracic procedures (p < 0.05). The overall mean knowledge assessment score improved from 42.5% presimulation to 78.6% postsimulation, (p < 0.0001). When stratified by procedure, the mean scores for each simulated procedure showed statistically significant improvement, except for ruptured diaphragm repair (p = 0.45). CONCLUSIONS: General thoracic surgery simulation provides a practical, inexpensive, and expedited learning experience in settings lacking experienced faculty and fellowship training opportunities. Resident feedback showed enhanced confidence and knowledge of thoracic procedures suggesting simulation surgery could be an effective tool in expanding the resident knowledge base and preparedness for performing clinically needed thoracic procedures. Repeated skills exposure remains a challenge for achieving sustainable progress.

The history of tuberculosis.

Tuberculosis has claimed its victims throughout much of known human history. It reached epidemic proportions in Europe and North America during the 18th and 19th centuries, earning the sobriquet, "Captain Among these Men of Death." Then it began to decline. Understanding of the pathogenesis of tuberculosis began with the work of Théophile Laennec at the beginning of the 19th century and was further advanced by the demonstration of the transmissibility of Mycobacterium tuberculosis infection by Jean-Antoine Villemin in 1865 and the identification of the tubercle bacillus as the etiologic agent by Robert Koch in 1882. Clemens von Pirquet developed the tuberculin skin test in 1907 and 3 years later used it to demonstrate latent tuberculous infection in asymptomatic children. In the late 19th and early 20th centuries sanatoria developed for the treatment of patients with tuberculosis. The rest provided there was supplemented with pulmonary collapse procedures designed to rest infected parts of lungs and to close cavities. Public Health measures to combat the spread of tuberculosis emerged following the discovery of its bacterial cause. BCG vaccination was widely employed following World War I. The modern era of tuberculosis treatment and control was heralded by the discovery of streptomycin in 1944 and isoniazid in 1952.

Phase III intergroup study of talc poudrage vs talc slurry sclerosis for malignant pleural effusion.

STUDY OBJECTIVE: To demonstrate the efficacy, safety, and appropriate mode of instillation of talc for sclerosis in treatment of malignant pleural effusions (MPEs). DESIGN: A prospective, randomized trial was designed to compare thoracoscopy with talc insufflation (TTI) to thoracostomy and talc slurry (TS) for patients with documented MPE. MEASUREMENTS: The primary end point was 30-day freedom from radiographic MPE recurrence among surviving patients whose lungs initially re-expanded > 90%. Morbidity, mortality, and quality of life were also assessed. RESULTS: Of 501 patients registered, those eligible were randomized to TTI (n = 242) or TS (n = 240). Patient demographics and primary malignancies were similar between study arms. Overall, there was no difference between study arms in the percentage of patients with successful 30-day outcomes (TTI, 78%; TS, 71%). However, the subgroup of patients with primary lung or breast cancer had higher success with TTI than with TS (82% vs 67%). Common morbidity included fever, dyspnea, and pain. Treatment-related mortality occurred in nine TTI patients and seven TS patients. Respiratory complications were more common following TTI than TS (14% vs 6%). Respiratory failure was observed in 4% of TS patients and 8% of TTI patients, accounting for five toxic deaths and six toxic deaths, respectively. Quality-of-life measurement demonstrated less fatigue with TTI than TS. Patient ratings of comfort and safety were also higher for TTI, but there were no differences on perceived value or convenience of the procedures. CONCLUSIONS: Both methods of talc delivery are similar in efficacy; TTI may be better for patients with either a lung or breast primary. The etiology and incidence of respiratory complications from talc need further exploration.

A proposed diagnostic approach to the patient with the subcentimeter pulmonary nodule: techniques that facilitate video-assisted thoracic surgery excision.

This article describes a diagnostic approach to the management of subcentimeter pulmonary nodules and delineates the contribution the chest surgeon brings to clinical decision making. This includes clinical experience and knowledge of nodule accessibility to thoracoscopic excisional biopsy based on the anticipated localization technique to be used. Characteristics of the ideal localization technique are discussed. Different localization techniques are then described, and their respective advantages and disadvantages are discussed. These techniques include intraoperative finger and instrument localization, preoperative radiologically placed hooks and coils, intraoperative ultrasonography, and preoperative placement of radiotracer markers.

The impact of tuberculosis on civilization.

Tuberculosis is an ancient disease that has spread in epidemic form among susceptible peoples but has had a little demographic or political impact on the populations it has inflicted. The disease continues to have a large economic impact on societies in which it is prevalent. Tuberculosis has left its mark on human creativity; on the lives of individuals in music, art, and literature; and dramatically on the advance of biomedical science and healthcare.

Pulmonary segmentectomy: results and complications.

BACKGROUND: Segmentectomy is an anatomic pulmonary parenchymal-sparing resection performed for certain benign lesions and on selected patients with lung cancer. We reviewed our experience with segmentectomy in this highly select group of patients. METHODS: We retrospectively reviewed the records of 61 patients (5% of all anatomic resections) undergoing 62 segmentectomies from 1991 to 2001. Wedge resections were excluded. The operative indications were suspected or known lung cancer (43), benign disease (12), and metastatic cancer to the lung (7). Median follow-up for patients with malignancy was 28 months (range 1 to 89 months). Actuarial survival was calculated using the Kaplan-Meier method. RESULTS: Segmentectomy was performed in 43 lung cancer patients with pathologic stages of Ia-22, Ib-14, IIa-2, IIb-1, IIIa/IIIb-2, and IV-2. All resection margins were negative for malignancy. Segmentectomy for benign diseases included granulomatous disease (5), pulmonary abscess (2), plasmacytoma (1), and others (4). Complications occurred in 39% (24/62) of patients, including atelectasis requiring bronchoscopy (10/62, 16%), pneumonia (9/62, 14%), air leak more than 7 days (5/62, 8%), and supraventricular dysrhythmias (6/62, 10%). In-hospital mortality was 3% (2 patients). Median length of hospital stay was 6 days (range 4 to 66 days). In the lung cancer patients the locoregional recurrence rate was 0% and the distant recurrence rate was 20%. The 4-year actuarial survival for patients with lung cancer was 72%. CONCLUSIONS: Pulmonary segmentectomy has acceptable morbidity and mortality in selected patients with both benign and malignant lung disease and remains a useful procedure in a thoracic surgeon's armamentarium. Distant, not locoregional recurrence, was responsible for the cancer deaths.

A novel technique for localization and excisional biopsy of small or ill-defined pulmonary lesions.

BACKGROUND: The purpose of this study was to develop and evaluate radiotracer-guided localization of small or ill-defined pulmonary nodules for thoracoscopic excisional biopsy. METHODS: This study consisted of two parts: a laboratory study in rats to determine the most suitable radiotracer, and a pilot study in humans to determine the feasibility of radiotracer lung nodule localization. The right lung of 12 rats was injected with a technetium 99m (Tc 99m) based radiotracer solution: 4 each with macroaggregated albumin (MAA), unfiltered sulfur colloid (SC), and pertechnetate (TcO(4)). Serial imaging was performed using a small animal gamma camera for 4 hours following injection. In 13 patients, computed tomographic (CT) guided injection of Tc 99m MAA solution was made into or adjacent to a pulmonary nodule suspicious for primary lung cancer. Gamma probe localization of the nodule was performed during subsequent thoracoscopic surgery. RESULTS: In the animal model, MAA provided more precise localization than SC or TcO(4) and was selected for the human study. In the human series, all 13 patients had successful gamma probe localization of their lesion. There were no radiologic or surgical complications. Seven of 13 nodules were malignant, and five of these nodules were stage IA primary lung carcinomas. CONCLUSIONS: Computed tomographic-guided radiotracer localization of small or ill-defined pulmonary nodules using Tc 99 m MAA before thoracoscopic excisional biopsy is feasible and may make excisional biopsy the preferred management strategy for the management of small pulmonary nodules in patients at high risk for malignancy.

Ventilation imaging of the lung: comparison of hyperpolarized helium-3 MR imaging with Xe-133 scintigraphy.

RATIONALE AND OBJECTIVES: To compare hyperpolarized helium-3 (HHe) magnetic resonance imaging (MRI) of the lung with standard Xe-133 lung ventilation scintigraphy. MATERIALS AND METHODS: We performed a retrospective review of 15 subjects who underwent HHe MRI and Xe-133 lung ventilation imaging. Coronal MRI sections were acquired after a single inhalation of HHe gas, and standard posterior planar lung ventilation scintigraphy was performed during continuous breathing of Xe-133 gas. The first breath scintigram of each patient was compared with a composite MR image composed of the sum of the individual MR images and with the individual helium-3 MR images. Ventilation defects on the two imaging modalities were compared for size, conspicuity, and concordance in presence and location. Assessment was done separately for each of four lung quadrants. RESULTS: Comparing the composite HHe MR images with Xe-133 scintigraphy, ventilation defect size, conspicuity and concordance were the same in 67% (40/60), 63% (38/60), and 62% (37/60) quadrants, respectively. Comparing the individual HHe MR image sections with the Xe-133 ventilation scan, there was concordance between the ventilation defects in 27% (16/60) of quadrants. More defects were identified on the individual HHe MR images in 62% (37/60) of quadrants. CONCLUSION: There was good agreement between composite HHe MR image and first breath Xe-133 scintigraphic images, supporting the widely held assumption that HHe MRI likely depicts first breath lung ventilation.

Phase I trial of intrapleural docetaxel administered through an implantable catheter in subjects with a malignant pleural effusion.

INTRODUCTION: Malignant pleural effusion (MPE) is a common complication in patients with advanced malignancy. This dose escalation phase I study was designed to determine the maximum tolerated dose of intrapleural docetaxel administered through an implantable catheter in subjects with MPE. METHODS: Subjects with MPE (n = 15) with median age of 64.6 years and an Eastern Cooperative Oncology Group performance status of 0 to 2 at baseline were enrolled into four single dose levels of docetaxel administered intrapleurally after drainage of the pleural effusion and insertion of an intrapleural catheter. The study determined the pharmacokinetic properties, clinical response, and toxicity profile of intrapleural docetaxel. RESULTS: All patients tolerated the therapy well and there were no significant toxicities. The majority of patients had a complete radiographic response. All patients receiving dose 100 mg/m2 or higher had a complete radiographic response. One dose-limiting toxicity was encountered in the dose 50 mg/m2. Pharmacokinetic data demonstrated peak plasma concentration of docetaxel between 30 minutes and 6 hours after infusion. Pleural exposure to docetaxel was 1000 times higher than systemic exposure. CONCLUSIONS: Single-dose intrapleural administration of doxetaxel is well tolerated in patients with MPE with minimal toxicity. The excellent clinical responses in this study after treatment with intrapleural doxetaxel suggest that further investigation is warranted.

Mechanical pleurodesis aided by peritoneal drainage: procedure for hepatic hydrothorax.

BACKGROUND: Hepatic hydrothorax in the setting of decompensated cirrhosis is a challenging and common clinical problem. Traditional therapies such as diuretics and transjugular intrahepatic portosystemic shunts can be effective therapies in selected patients but in patients ineligible for, or intolerant of, these traditional therapies, few effective therapeutic options remain for the management of hepatic hydrothorax. METHODS: We present a series of 5 consecutive patients with refractory hepatic hydrothorax who underwent combined thorascopically guided mechanical and chemical pleurodesis aided by an intraperitoneal drain that prevented reaccumulation of the ascites while pleural inflammation and adhesion were progressing. We speculate that the prolonged contact between the parietal and visceral pleura allowed by prevention of reaccumulation of intraabdominal ascites and subsequent flux through the pleural space enhanced the efficacy of this procedure in comparison with those presented in the literature. RESULTS: Despite the fact that all of our patients presented with decompensated cirrhosis, the surgical procedure and subsequent hospitalization were tolerated well by our entire cohort. Colonization of the pleural and peritoneal drainage fluid was a common complication of this procedure but was not associated with prolonged morbidity or mortality. CONCLUSIONS: We present a therapy for the difficult clinical problem of refractory hepatic hydrothorax that may allow selected patients an opportunity for prolonged symptomatic control.

Preoperative embolization of Castleman's disease using microspheres.

Castleman's disease is a rare form of lymph node hyperplasia most commonly presenting as a solitary hypervascular mediastinal mass. Surgical resection is the treatment of choice, but this can be associated with significant blood loss due to its hypervascularity. We report two cases with a preoperative diagnosis of mediastinal Castleman's disease in whom preoperative embolization with Trisacryl gelatin microspheres (Biosphere Medical, Rockland, MA) was performed. Compared with the literature, a decrease in the amount of perioperative bleeding was noted in both cases.

Quality of life following primary vs. redo transthoracic paraesophageal hernia repairs.

The purpose of this study was to compare the quality of life (QOL) and functional results of 42 patients undergoing primary (60%) and 23 patients undergoing redo (40%) transthoracic paraesophageal hernia repairs. All patients had a floppy Nissen or Belsey anti-reflux repair with or without a Collis gastroplasty. Morbidity occurred in 12% of patients and was similar between groups (P=1.0). Overall QOL scores were not different between groups. Patients undergoing initial repair were found to have significantly higher QOL scores related to their GERD symptoms (P=0.02). Postoperative GERD symptom scores were not significantly different between groups for heartburn, regurgitation, epigastric/chest pain, or cough. Redo patients had more bloating (P=0.02) and dysphagia (P=0.04). Overall, total GERD scores were higher in the redo group compared to the initial group indicating worse GERD-related dysfunction in the redo group (15.8+/-3.8 vs. 6.3+/-1.6, P=0.03). Functional and QOL analysis of transthoracic paraesophageal hernia repairs indicates that redo procedures are associated with a higher incidence of specific gastrointestinal symptoms and worse GERD-related QOL when compared to initial procedures. These differences, while statistically significant, have limited clinical relevance as the overall QOL was not different between groups and low GERD symptom scores were found in both groups.

Identification of small lung nodules: technique of radiotracer-guided thoracoscopic biopsy.

BACKGROUND: This study describes a thoracoscopic technique to reliably locate and excise lung nodules that were not thought to be thoracoscopically visible or instrumentally palpable. METHODS: Initial laboratory studies succeeded in selecting a technetium 99m gamma-emitting solution, technetium 99m macro-aggregated albumin, that remained localized in lung parenchyma after percutaneous placement. Subsequently, 84 patients with solitary small nodules underwent computed tomography (CT)-guided percutaneous placement of this technetium solution in or near the nodule. Thoracoscopic localization with a radioprobe and excisional biopsy followed. RESULTS: In 3 patients, the previous lesion was not present on the CT scan done on the day of surgery. The 81 remaining patients underwent radiotracer placement and operation. No tracer activity was present in the lung in 4 patients, and open thoracotomy was necessary to locate the lesion. The lesion was successfully localized and excised in 77 patients (95.1%), and 71 underwent thoracoscopic excisional biopsy. Four underwent intentional thoracotomy for deep small nodules in which the tracer was used to guide the open biopsy. Two required conversion from thoracoscopy to thoracotomy because the anatomic location of the lesion prevented a thoracoscopic staple excision. Fifty percent of the lesions were benign, 39% were primary lung cancers, and additional 11% were either solitary metastatic lesions or lymphoma. No patients died, and morbidity rate was 16% (arrhythmias or pneumothoraces). CONCLUSIONS: Radiotracer-guided thoracoscopic biopsy was 95% reliable for subsequent surgical successful localization and excision of small nodules. This technique can be expanded to localize deep lesions for open thoracotomy and be used to prevent thoracotomy in 50% of patients with benign disease.

Effects of induction immunosuppression regimen on acute rejection, bronchiolitis obliterans, and survival after lung transplantation.

OBJECTIVE: Effects of daclizumab and antithymocyte globulin induction on acute rejection, bronchiolitis obliterans syndrome, and survival after lung transplantation are unknown. We hypothesized that daclizumab results in less acute rejection and bronchiolitis obliterans and better survival than antithymocyte globulin. METHODS: Consecutive adult lung transplants (n = 163) at the University of Virginia from January 1998 to May 2006 were reviewed. Antithymocyte globulin induction was routinely performed before January 2002 (65 patients), after which all patients received daclizumab (98 patients). Estimates of cumulative event rate of acute rejection, bronchiolitis obliterans, and death were calculated by Kaplan-Meier method and between-group differences compared by log-rank test. Cox proportional hazards models were fitted to assess treatment effects adjusted for covariates. RESULTS: Groups were similar in demographics and preoperative and intraoperative risk factors. Maintenance immunosuppression changed during the study, and mycophenolate mofetil was more commonly given to patients receiving daclizumab. By Kaplan-Meier method, daclizumab was associated with significantly less acute rejection (P = .002), less bronchiolitis obliterans (P = .02), and improved overall survival (P = .04). Induction agent was highly associated with acute rejection (P = .002), bronchiolitis obliterans (P = .02), and mortality (P = .05); antimetabolite agent was associated only with acute rejection (P = .01). Adjusting for covariates, induction agent remained significantly predictive for acute rejection (P = .02) and bronchiolitis obliterans (P = .05), approaching significance for survival (P = .07). CONCLUSION: Lung transplant recipients receiving daclizumab for induction had significantly less acute rejection and bronchiolitis obliterans than those receiving antithymocyte globulin, with possibly improved survival. Improvements in acute rejection may have been confounded by the use of mycophenolate mofetil.