Minimally Invasive Approach of a Retrocaval Ureter

The retrocaval ureter is a rare congenital entity, classically managed with open pyeloplasty techniques. The experience obtained with the laparoscopic approach of other more frequent causes of ureteropelvic junction (UPJ) obstruction has opened the method for the minimally invasive approach of the retrocaval ureter. In our paper, we describe a clinical case of a right retrocaval ureter managed successfully with laparoscopic dismembered pyeloplasty. The main standpoints of the procedure are described. Our results were similar to others published by other urologic centers, which demonstrates the safety and feasibility of the procedure for this condition.

Intrapleural analgesis following endoscopic scoliosis correction

Endoscopic scoliosis correction plays an important part in the surgical options available for treating adolescent idiopathic scoliosis. However, there is a paucity of literature examining optimum methods of analgesia following this type of surgery. The role of intrapleural analgesia is examined and described. In this study, local anaesthetic administration via an intrapleural catheter was found to be a safe and effective method of analgesia following endoscopic scoliosis correction. Post-operative pain following anterior scoliosis correction can be reduced to ‘mild’ levels by combined analgesia regimes. Surgeons may wish to expand its use into open or minimally invasive anterior scoliosis correction or anterior releases.

Stimulation of osteogenesis and angiogenesis of hBMSCs by delivering Si ions and functional drug from mesoporous silica nanospheres

Multifunctional bioactive materials with the ability to stimulate osteogenesis and angiogenesis of stem cells play an important role in the regeneration of bone defects. However, how to develop such biomaterials remains a significant challenge. In this study, we prepared mesoporous silica nanospheres (MSNs) with uniform sphere size (∼90 nm) and mesopores (∼2.7 nm), which could release silicon ions (Si) to stimulate the osteogenic differentiation of human bone marrow stromal cells (hBMSCs) via activating their ALP activity, bone-related gene and protein (OCN, RUNX2 and OPN) expression. Hypoxia-inducing therapeutic drug, dimethyloxaloylglycine (DMOG), was effectively loaded in the mesopores of MSNs (D-MSNs). The sustained release of DMOG from D-MSNs could stabilize HIF-1α and further stimulated the angiogenic differentiation of hBMSCs as indicated by the enhanced VEGF secretion and protein expression. Our study revealed that D-MSNs could combine the stimulatory effect on both osteogenic and angiogenic activity of hBMSCs. The potential mechanism of D-MSN-stimulated osteogenesis and angiogenesis was further elucidated by the supplementation of cell culture medium with pure Si ions and DMOG. Considering the easy handling characteristics of nanospheres, the prepared D-MSNs may be applied in the forms of injectable spheres for minimally invasive surgery, or MSNs/polymer composite scaffolds for bone defect repair. The concept of delivering both stimulatory ions and functional drugs may offer a new strategy to construct a multifunctional biomaterial system for bone tissue regeneration.

Flexible pneumatic micro-actuators: Analysis and production

Compliant pneumatic micro-actuators are interesting for applications requiring large strokes and forces in delicate environments. These include for instance minimally invasive surgery and assembly of microcomponents. This paper presents a theoretical and experimental analysis of a balloon-type compliant micro-actuator. Finite element modeling is used to describe the complex behavior of these actuators, which is validated through prototype experiments. Prototypes with dimensions ranging from 11mm × 2mm × 0.24mm to 4mm × 1mm × 0.12mm are fabricated by a newly developed production process based on micromilling and micromolding. The larger actuators are capable of delivering out-of-plane strokes of up to 7mm. Further, they have been integrated in a platform with two rotational and one translational degree of freedom. © 2011 Published by Elsevier Ltd.

A comparison between randomly alternating imaging, normal laparoscopic imaging, and virtual reality training in laparoscopic psychomotor skill acquisition

Objectives: To evaluate virtual reality as a laparoscopic training device in helping surgeons to automate to the “fulcrum effect” by comparing it to time-matched training programs using randomly alternating images (ie, y-axis inverted and normal laparoscopic) and normal laparoscopic viewing conditions.

Methods: Twenty-four participants (16 females and 8 males), were randomly assigned to minimally invasive surgery virtual reality (MIST VR), randomly alternating (between y-axis inverted and normal laparoscopic images), and normal laparoscopic imaging condition. Participants were requested to perform a 2-minute laparoscopic cutting task before and after training.

Results: In the test trial participants who trained on the MIST VR performed significantly better than those in the normal laparoscopic and randomly alternating imaging conditions.

Conclusion: The results show that virtual reality training may provide faster skill acquisition with particular reference to automation of the fulcrum effect. MIST VR provides a new way of training laparoscopic psychomotor surgical skills.

Impacto en el entrenamiento con simuladores de laparoscopia dentro del programa de Cirugía General-Universidad del Rosario

Introducción: La cirugía laparoscópica ocupa un lugar privilegiado dentro de la cirugía mínimamente invasiva, brindando al paciente y a las instituciones hospitalarias importantes beneficios comparados con la cirugía convencional. Los cirujanos en formación deben contar con un entrenamiento adecuado en cirugía laparoscópica basado en simuladores previo a la práctica con pacientes, disminuyendo la morbimortalidad derivada de la curva de aprendizaje. Este estudio busca describir e identificar los cambios en habilidades y tiempos quirúrgicos antes y después del entrenamiento con simulador de bajo costo y simulador virtual. Metodología: Se realizó un seudoexperimento (antes y después) con 20 residentes de los cuales 18 completaron el estudio, quienes recibieron un entrenamiento dirigido para la realización de procedimientos por vía laparoscópica en simuladores. El análisis estadístico se realiza mediante un análisis uni y bivariado, y se determina la significancia estadística con la medición de X2 y prueba exacta de Fisher así como la prueba T Student para muestras emparejadas y Wilcoxon para las variables numéricas. Resultados: El simulador de bajo costo muestra dependencia en la variable de manejo de tejidos en el ejercicio 3 y 10, con valores de p=0.035, y p=0.028 respectivamente. El 60% de los ejercicios muestra una diferencia estadísticamente significativa en el tiempo empleado en las pruebas. Para simulador virtual, todos los ejercicios mostraron diferencias significativas en al menos una de las variables evaluadas. Conclusiones: El entrenamiento, tanto con el simulador de bajo costo como con el simulador virtual, mejora las habilidades quirúrgicas necesarias para la realización de un procedimiento laparoscópico.

Aplicación de una técnica mínimamente invasiva para la reparación de ruptura del tendón de Aquiles

Introducción Las rupturas agudas del tendón de Aquiles se presentan en pacientes entre 40 y 50 años. Las causas más comunes son actividades deportivas. Se han descrito técnicas mínimamente invasivas, con complicaciones como infección del sitio operatorio, adherencias y la lesión del nervio sural. El propósito de este estudio es determinar el desenlace clínico y funcional, de los pacientes con rupturas agudas del tendón de Aquiles llevados a reparación quirúrgica mínimamente invasiva entre 2011 y 2013 en nuestra institución. Materiales y métodos. Estudio tipo Serie de casos. Se realizó evaluación de fuerza muscular, fatiga muscular, arcos de movilidad con respecto a la extremidad contralateral, la escala AOFAS y se describieron las complicaciones. Resultados. Se evaluaron 21 pacientes de 31 elegibles, diecisiete hombres y cuatro mujeres. Edad promedio de 42,7 años, duración promedio de seguimiento de 17,47 meses. Como complicación hubo una dehiscencia de sutura treinta días después del procedimiento. Los pacientes regresaron a actividades laborales 48 días después de cirugía. El tiempo promedio de retorno a actividades deportivas fue de 8.47 meses. El puntaje promedio en la escala AOFAS fue 90. Los arcos de movilidad del tobillo fueron en promedio de 52° para el lado afectado y 56° en el no intervenido. El número de repeticiones de elevación de talón de la extremidad afectada fue de 58 en promedio. Discusión. Estos resultados sugieren que la técnica mínimamente invasiva para reparación del tendón de Aquiles provee resultados funcionales satisfactorios a corto y mediano plazo con bajas tasas de complicación.

Haptics in medicine and clinical skill acquisition

THE clinical skills of medical professionals rely strongly on the sense of touch, combined with anatomical and diagnostic knowledge. Haptic exploratory procedures allow the expert to detect anomalies via gross and fine palpation, squeezing, and contour following. Haptic feedback is also key to medical interventions, for example when an anaesthetist inserts an epidural needle, a surgeon makes an incision, a dental surgeon drills into a carious lesion, or a veterinarian sutures a wound. Yet, current trends in medical technology and training methods involve less haptic feedback to clinicians and trainees. For example, minimally invasive surgery removes the direct contact between the patient and clinician that gives rise to natural haptic feedback, and furthermore introduces scaling and rotational transforms that confuse the relationship between movements of the hand and the surgical site. Similarly, it is thought that computer-based medical simulation and training systems require high-resolution and realistic haptic feedback to the trainee for significant training transfer to occur. The science and technology of haptics thus has great potential to affect the performance of medical procedures and learning of clinical skills. This special section is about understanding

Isolation of novel multipotent neural crest-derived stem cells from adult human inferior turbinate

Adult human neural crest-derived stem cells (NCSCs) are of extraordinary high plasticity and promising candidates for the use in regenerative medicine. Here we describe for the first time a novel neural crest-derived stem cell population within the respiratory epithelium of human adult inferior turbinate. In contrast to superior and middle turbinates, high amounts of source material could be isolated from human inferior turbinates. Using minimally-invasive surgery methods isolation is efficient even in older patients. Within their endogenous niche, inferior turbinate stem cells (ITSCs) expressed high levels of nestin, p75(NTR), and S100. Immunoelectron microscopy using anti-p75 antibodies displayed that ITSCs are of glial origin and closely related to nonmyelinating Schwann cells. Cultivated ITSCs were positive for nestin and S100 and the neural crest markers Slug and SOX10. Whole genome microarray analysis showed pronounced differences to human ES cells in respect to pluripotency markers OCT4, SOX2, LIN28, and NANOG, whereas expression of WDR5, KLF4, and c-MYC was nearly similar. ITSCs were able to differentiate into cells with neuro-ectodermal and mesodermal phenotype. Additionally ITSCs are able to survive and perform neural crest typical chain migration in vivo when transplanted into chicken embryos. However ITSCs do not form teratomas in severe combined immunodeficient mice. Finally, we developed a separation strategy based on magnetic cell sorting of p75(NTR) positive ITSCs that formed larger neurospheres and proliferated faster than p75(NTR) negative ITSCs. Taken together our study describes a novel, readily accessible source of multipotent human NCSCs for potential cell-replacement therapy.

Laparoscopic evaluation and treatment of the impalpable testis

Objectives: To evaluate the laparoscopic technique as a diagnostic and therapeutic tool in the management of patients with impalpable testis. Material and Methods: Fifty-nine patients with mean age of 6.3 years underwent laparoscopy to evaluate 85 impalpable testes that were classified as absent, canalicular and intra-abdominal. In the case of testicular absence, the procedure was terminated. In the case of canalicular testis, open inguinal exploration was performed. In intra-abdominal testis, either laparoscopic orchiopexy or orchiectomy was performed. According to the length of the vascular pedicle, orchipexy was performed either with or without vascular ligature. Post-operatively, the treated testes were evaluated according to size and location in the scrotum. Results: Seventeen (20%) of the 85 impalpable testes were diagnosed as absent, 21 (24.7%) as canalicular and 47 (55.3%) as intra-abdominal. Of the canalicular testes, 20 were explored by inguinotomy and one by laparoscopy. All the intra-abdominal testes were treated initially by laparoscopy, four being removed due to atrophy, 31 submitted to vascular ligature and 12 to primary orchipexy. Of those submitted to vascular ligature, 22 underwent a second stage orchipexy, of which 18 laparoscopically and 4 by inguinotomy. Of the 18 testes brought to the scrotum by staged laparoscopic orchipexy, 15 (83.3%) presented normal characteristics in the late follow-up, while of the 12 submitted to primary laparoscopic orchipexy, 8 (66.6%) were normal. There were no perioperative or late complications. Conclusions: Laparoscopy is a minimally invasive procedure with low morbidity that enables precise diagnosis of the impalpable testes. When intra-abdominal testes are found, either immediate laparoscopic orchiectomy, or primary and staged orchipexy are possible, with results equivalent to open procedures, with the advantage of smaller surgical incisions and shorter postoperative recovery.

Comparative Analysis of 2 Techniques of Double-Gloving Protection During Arch Bar Placement for Intermaxillary Fixation

Purpose: This study was conducted to comparatively evaluate, in a prospective and randomized manner, 2 techniques for providing double-gloving protection during arch bar placement for intermaxillary fixation. Materials and Methods: A total of 42 consecutive patients in whom application of an Erich bar was indicated for intermaxillary fixation were equally divided into 2 groups. In group 1, 2 sterile surgical gloves were used; in group 2, a nonsterile disposable inner glove was used under a sterile surgical glove. Wilcoxon, Mann-Whitney, Kruskal-Wallis, and binomial statistical tests were used to analyze the findings. Results: A total of 103 perforations were found in the outer gloves (47 in group 1 and 56 in group 2), along with 5 perforations in inner gloves in both groups (α = .01). No significant statistical difference was found between groups in terms of inner glove perforations (α = .05). The nondominant hand presented with 70.9% of the perforations, statistically significant to 1%. Conclusions: Both double-gloving techniques were found to provide effective clinician protection. The use of a nonsterile disposable glove under the surgical glove is possible for less-invasive procedures, offering the same safety as using 2 sterile surgical gloves while decreasing operational costs. This method does not eliminate the need to change gloves when a perforation is suspected or noted during the surgery, however. © 2007 American Association of Oral and Maxillofacial Surgeons.

Arthrocentesis procedure: Using this therapeutic maneuver for TMJ closed lock management

Temporomandibular joint (TMJ) disorder is a term that encompasses a number of overlapping conditions, such as closed lock. Closed lock of the TMJ is considered a consequence of a nonreducing deformed disc acting as an obstacle to the sliding condylar head that usually causes a decrease in the maximum mouth opening and acute pain. The management of the TMJ is still controversial. Thus, arthrocentesis of the TMJ is a valuable modification of the traditional method of arthroscopic lavage, which consists of washing the joint in order to remove chemical inflammatory mediators and intra-articular adhesions, changing intra-articular pressure. TMJ disorder has always presented as a therapeutic challenge to maxillofacial surgeons. Therefore, this paper aimed to describe a clinical report of a closed lock of the left TMJ in a 19-year-old female subject who was successfully treated by arthrocentesis procedure. © 2013 by Mutaz B. Habal, MD.