Experimental model standardizing polyvinyl alcohol hydrogel to simulate endoscopic ultrasound and endoscopic ultrasound-elastography

BACKGROUND Endoscopic ultrasound(EUS) and endoscopic ultrasound elastography(EUS-E) simulation lessens the learning curve; however, models lack realism, diminishing competitiveness.AIM To standardize the mechanical properties of polyvinyl alcohol(PVA) hydrogel for simulating organs and digestive lesions.METHODS PVA hydrogel(Sigma Aldrich, degree of hydrolysis 99%) for simulating EUS/EUS-E lesions was investigated in Unidad de Investigación y Desarrollo Tecnológico at Hospital General de México "Dr. Eduardo Liceaga", Mexico City. We evaluated physical, contrast, elasticity and deformation coefficient characteristics in lesions, applying Kappa's concordance and satisfaction questionnaire(Likert 4-points).RESULTS PVA hydrogel showed stable mechanical properties. Density depended on molecular weight(MW) and concentration(C). PVA bblocks with the greatest density showed lowest tensile strength(r =-0.8, P = 0.01). Lesions were EUSgraphically visible. Homogeneous and heterogeneous examples were created from PVA blocks or PVA phantoms, exceeding(MW_2 = 146000-186000, C_9 = 15% and C_(10) = 20%) with a density under(MW_1 = 85000-124000, C_1 = 7% and C_2 = 9%). We calculated elasticity and deformation parameters of solid(blue) areas, contrasting with the norm(Kappa = 0.8; high degree of satisfaction).CONCLUSION PVA hydrogels were appropriate for simulating organs and digestive lesions using EUS/EUS-E, facilitating practice and reducing risk. Repetition amplified skills, while reducing the learning curve.     

Laparoscopic Resection of a Symptomatic Parasitic Leiomyoma of Paravesical and Obturator Fossa

Study ObjectiveTo show laparoscopic management of a symptomatic parasitic leiomyoma of paravesical and obturator fossa.DesignEdited video demonstrating a step-by-step explanation of the surgical technique of this case.SettingUniversity hospital.InterventionsUterine leiomyomas are the most common benign pelvic tumors in women. They occur in approximately 25% of women of reproductive age. Parasitic leiomyomas are rare, with few cases reported in the literature [1,2]. They are classified according to their location in relation to the myometrium. Parasitic leiomyomas are in group 8 of the International Federation of Gynecology and Obstetrics classification [3].It is not clear why they are produced; it is thought that they could derive from subserous leiomyomas that achieved a blood supply from neighboring structures outside the uterus [1,3].They can also have iatrogenic origin in patients who have undergone previous surgery such as myomectomy with power morcellation use [4].We present the case of a 32-year-old women, gravida 1 para 1, without previous pelvic surgery. She complained of lower back and sacrum pain and nonspecific discomfort in her inner thigh. Her physical examination showed a 6- to 7-cm solid right paravaginal tumor. Ultrasonography and nuclear magnetic resonance confirmed the presence of a 7 × 5-cm solid tumor in the right paravesical and obturator fossa. The diagnosis of a probable parasitic myoma was proposed, and a laparoscopic resection was scheduled. The video demonstrates the surgical technique with special emphasis on the anatomy of the surgical site. The patient was discharged 24 hours after surgery without complications. The final pathology confirmed uterine leiomyoma.Written informed consent was requested according to the regulations of our institution.ConclusionA successful laparoscopic resection of a symptomatic parasitic leiomyoma of the paravesical and obturator fossa was achieved. The importance of knowledge of the pelvic anatomy for the management of this type of case is underlined.     

First case of multidrug-resistant tuberculosis caused by a rare “Beijing-like” genotype of Mycobacterium tuberculosis in Bogotá, Colombia

This report describes a first case due to a genetically distinct and relatively rare “Beijing-like” strain of Mycobacterium tuberculosis isolated from a 15 years old female patient who died shortly after the initiation of antituberculous therapy with second-line drugs. Positive cultures obtained from lung, kidney and adrenal glands upon autopsy were identified as Mycobacterium tuberculosis complex characterized by an identical 15-banded IS6110-RFLP pattern, and were found to be resistant to all the 4 first-line antituberculous drugs tested (rifampin, isoniazid, ethambutol and streptomycin). Spoligotyping followed by comparison with the SITVIT2 database revealed that the isolate belonged to a rare pattern identified as Spoligotype International Type SIT190, which represents only 1.7% of all the Beijing strains worldwide. We present data on its worldwide distribution and present an evolutionary scenario based on available MIRU typing data.