Analysis of tissue inflammatory response, fibroplasia, and foreign body reaction between the polyglactin suture of abdominal aponeurosis in rats and the intraperitoneal implant of polypropylene, polypropylene/polyglecaprone and polyester/porcine collagen meshes

ABSTRACT Purpose To compare tissue inflammatory response, foreign body reaction, fibroplasia, and proportion of type I/III collagen between closure of abdominal wall aponeurosis using polyglactin suture and intraperitoneal implant of polypropylene, polypropylene/polyglecaprone, and polyester/porcine collagen meshes to repair defects in the abdominal wall of rats. Methods Forty Wistar rats were placed in four groups, ten animals each, for the intraperitoneal implant of polypropylene, polypropylene/polyglecaprone, and polyester/porcine collagen meshes or suture with polyglactin (sham) after creation of defect in the abdominal wall. Twenty-one days later, histological analysis was performed after staining with hematoxylin-eosin and picrosirius red. Results The groups with meshes had a higher inflammation score (p < 0.05) and higher number of gigantocytes (p < 0.05) than the sham group, which had a better fibroplasia with a higher proportion of type I/III collagen than the tissue separating meshes (p < 0.05). There were no statistically significant differences between the three groups with meshes. Conclusions The intraperitoneal implant of polypropylene/polyglecaprone and polyester/porcine collagen meshes determined a more intense tissue inflammatory response with exuberant foreign body reaction, immature fibroplasia and low tissue proportion of type I/III collagen compared to suture with polyglactin of abdominal aponeurosis. However, there were no significant differences in relation to the polypropylene mesh group.

Use of an Expanded Polytetrafluoroethylene (ePTFE) Dura Substitute in Glioma Surgeries: A Technical Note

Introduction Reoperations are a common scenario among glioma patients. There is crescent evidence of its benefit in low- and high-grade gliomas. Here we discuss our experience with inert expanded polytetrafluoroethylene (ePTFE) dura substitute in glioma surgeries. Technical note We generally put the ePTFE dura substitute below the dura of the patient, even if it is intact. This membrane should be sutured in place using a tensionfree technique, with 4-0 polypropylene. Expanded polytetrafluoroethylene minimizes tissue attachment and fibrosis when performing reoperation in glioma patients. Discussion Since the literature has shown benefits in survival with reoperation in glioma patients, the use of ePTFE dura substitute can improve surgical time and minimize complications in a second surgery.

Comparative study of peritoneal adhesions after intraperitoneal implantation in rats of meshes of polypropylene versus polypropylene/polyglecaprone versus polyester/porcine collagen

Abstract Purpose To Compare the extent and intensity of adhesions formed between the intra-abdominal organs and the intraperitoneal implants of polypropylene mesh versus polypropylene/polyglecaprone versus polyester/porcine collagen used for correction of abdominal wall defect in rats. Methods After the defect in the abdominal wall, thirty Wistar rats were placed in three groups (ten animals each) for intraperitoneal mesh implant: polypropylene group, polypropylene/polyglecaprone group, and polyester/porcine collagen group. The macroscopic evaluation of the extent and intensity of adhesions was performed 21 days after the implant. Results The polypropylene group had a higher statistically significant impairment due to visceral adhesions (p value = 0.002) and a higher degree of intense adherence in relation to polypropylene/polyglecaprone and polyester/porcine collagen groups (p value<0.001). The polyester/porcine collagen group showed more intense adhesions than the polypropylene/polyglecaprone group (p value=0.035). Conclusions The intraperitoneal implantation of polypropylene meshes to correct defects of the abdominal wall caused the appearance of extensive and firm adhesions to intra-abdominal structures. The use of polypropylene/polyglecaprone or polyester/porcine collagen tissue-separating meshes reduces the number and degree of adhesions formed.

Comparative study of four different types of intraperitoneal mesh prostheses in rats

Abstract Purpose: To compare four types of mesh regarding visceral adhesions, inflammatory response and incorporation. Methods: Sixty Wistar rats were divided into four groups, with different meshes implanted intraperitoneally: polytetrafluoroethylene (ePTFE group); polypropylene with polydioxanone and oxidized cellulose (PCD); polypropylene (PM) and polypropylene with silicone (PMS). The variables analyzed were: area covered by adhesions, incorporation of the mesh and inflammatory reaction (evaluated histologically and by COX2 immunochemistry). Results: The PMS group had the lowest adhesion area (63.1%) and grade 1 adhesions. The ePTFE and PM groups presented almost the total area of their surface covered by adherences (99.8% and 97.7% respectively) The group ePTFE had the highest percentage of area without incorporation (42%; p <0.001) with no difference between the other meshes. The PMS group had the best incorporation rate. And the histological analysis revealed that the inflammation scores were significantly different. Conclusions: The PM mesh had higher density of adherences, larger area of adherences, adherences to organs and percentage of incorporation. ePTFE had the higher area of adherences and lower incorporation. The PMS mesh performed best in the inflammation score, had a higher incorporation and lower area of adherences, and it was considered the best type of mesh.

Comparative study of fibrosis induced by Marlex®, Parietex Composite®, Vicryl® and Ultrapro® meshes1

Abstract Purpose: To evaluate the fibrosis induced by four different meshes: Marlex®, Parietex Composite®, Vicryl® and Ultrapro®. Methods: Histological cutouts of abdominal wall were analyzed with polarized light 28 days after the meshes implants and colorized by picrosirius to identify the intensity of collagen types I and III, and their maturation index. Results: When the four groups were compared, the total collagen area analyzed was bigger in groups A and D, with no difference between them. The collagen type I density was bigger in group A, with an average of 9.62 ± 1.0, and smaller in group C, with an average of 3.86 ± 0.59. The collagen type III density was similar in groups A, B and C, and bigger in group D. The collagen maturation index was different in each of the four groups, bigger in group A with 0.87, group B with 0.66, group D with 0.57 and group C with 0.33 (p = 0.0000). Conclusion: The most prominent fibrosis promotion in the given meshes was found on Marlex® (polypropylene mesh) and the Parietex Composite® (non-biodegradable polyester); the collagen maturation index was higher in the Marlex® mesh, followed by Ultrapro®, Parietex Composite® and Vicryl® meshes.

Pro - inflammatory cytokines and metalloproteinase activation in polypropylene mesh implant in rat subcutaneous tissue

ABSTRACT Aims and Objectives: Polypropylene meshes have been increasingly adopted for correction of pelvic organ prolapse due to its lower recurrence rate when compared to surgeries without meshes. The study of the interaction of these materials with the host tissue may contribute to the development of materials with best biocompatibility and, consequently, less complication rates. Materials and Methods: The present study compares the inflammatory reaction of standard-weight (SW) and lightweight (LW) meshes (72 g/m216g/m2 respectively), implanted in the abdomen of 20 adult rats, which were euthanized in four or 30 days. Quantification of pro-inflammatory markers, IL-1 and TNF-α, and of metalloproteinases, MMP2 and MMP3, were carried out through immunohistochemistry with AxioVision® software. Results: There were no significant differences in the quantification of IL-1 and TNF-α in LW versus SW meshes. However, IL-1 quantification increased along time (30 days >4 days, p=0.0269). Also, MMP-2 quantification was similar to SW and LW and both presented a significant increase along time (30 days >4 days, p <0.0001). MMP-3 quantification also showed no difference between the SW and LW groups, but increased along time (30 days >4 days, p=0.02). Conclusions: Mesh's density did not influence the quantification of pro-inflammatory cytokines IL-1 and TNF-α and metalloproteinases 2 and 3. The increased expression of IL-1, MMP-2 and MMP-3 over time could represent a longstanding inflammatory response after PP mesh implantation. Possibly, the occurrence of adverse events following PP prosthetic implants can be influenced by other factors, not solely related to the amount of implanted material.

Treatment of abdominal wall hernia with suture, or polypropylene, or collagen prosthesis

ABSTRACT PURPOSE: To develop an experimental model for incisional hernias and to compare morphological and functional aspects of hernia repairs by suture, polypropylene mesh and collagen mesh. METHODS: A defect measuring 7cm x 2cm was created in the anterior abdominal of 28 New Zealand male rabbits, divided into four groups (n = 7): (1) control, (2) suture of the anterior sheath of the rectus abdominal muscle, (3) setting of polypropylene mesh, and (4) setting of collagen mesh. On the 90th postoperative day, the animals were examined to verify the presence of incisional hernia. Samples of abdominal wall and scar were collected for histological study. RESULTS: Incisional hernia was identified in 85.7% of the control group, 57.1% of the suture group, 42.9% of the collagen mesh group, and none in the polypropylene mesh group (p = 0.015). Mesh exposure could be identified in 71.4% of the animals in group 3 and in no animal in group 4 (p = 0.021). The polypropylene mesh is effective in the treatment of abdominal wall defects, causing an intense inflammatory reaction. CONCLUSION: The collagen mesh is biocompatible, producing a minimal inflammatory reaction, but fails in the treatment of abdominal wall defects.

Host inflammatory response to polypropylene implants: insights from a quantitative immunohistochemical and birefringence analysis in a rat subcutaneous model

ABSTRACT Objectives To describe acute and sub acute aspects of histological and immunohistochemical response to PP implant in a rat subcutaneous model based on objective methods. Materials and Methods Thirty rats had a PP mesh subcutaneously implanted and the same dissection on the other side of abdomen but without mesh (sham). The animals were euthanized after 4 and 30 days. Six slides were prepared using the tissue removed: one stained with hematoxylin-eosin (inflammation assessment); one unstained (birefringence evaluation) and four slides for immunohistochemical processing: IL-1 and TNF-α (pro-inflammatory cytokines), MMP-2 (collagen metabolism) and CD-31 (angiogenesis). The area of inflammation, the birefringence index, the area of immunoreactivity and the number of vessels were objectively measured. Results A larger area of inflammatory reaction was observed in PP compared to sham on the 4th and on the 30th day (p=0.0002). After 4 days, PP presented higher TNF (p=0.0001) immunoreactivity than sham and no differences were observed in MMP-2 (p=0.06) and IL-1 (p=0.08). After 30 days, a reduction of IL-1 (p=0.010) and TNF (p=0.016) for PP and of IL-1 (p=0.010) for sham were observed. Moreover, area of MMP-2 immunoreactivity decreased over time for PP group (p=0.018). Birefringence index and vessel counting showed no differences between PP and sham (p=0.27 and p=0.58, respectively). Conclusions The implantation of monofilament and macroporous polypropylene in the subcutaneous of rats resulted in increased inflammatory activity and higher TNF production in the early post implant phase. After 30 days, PP has similar cytokines immunoreactivity, vessel density and extracellular matrix organization.

Mamoplastia pós-cirurgia bariátrica usando suporte protético complementar de contenção glandular / Breast augmentation after bariatric surgery by using complementary prosthetic support for glandular containment

INTRODUÇÃO: A pele de pacientes emagrecidas pós-cirurgia bariátrica apresenta alterações estruturais e proteômicas e não resiste ao peso das mamas, levando-as à flacidez residual precoce, exigindo suporte auxiliar. O objetivo é aplicar suporte auxiliar de lâmina de polipropileno não absorvível mais poliglecaprone absorvível ou lâmina de silicone de bustos, em forma de "soutien interno" como auxiliar de sustentação da pele, para manutenção da forma das mamas, e flacidez no mínimo comparável a outras pacientes sem emagrecimento pela cirurgia bariátrica. MÉTODOS: Nove pacientes foram submetidas à mamoplastia em T invertido com modelagem dos tecidos mamários, com redução do volume e envolvidos com lâmina de sustentação auxiliar. RESULTADOS: Não houve flacidez precoce e em observação de até 4 anos ela era aceitável. Uma delas apresentou seroma, drenado com boa resolução. Serão operadas outras 24 pacientes dentro do protocolo, acompanhadas e observadas por 2 anos com controle mamográfico, ultrassônico e ressonância magnética. CONCLUSÃO: A mamoplastia redutora pós-cirurgia bariátrica requer suporte extra à glândula mamária. A pele estruturalmente alterada não suporta o seu peso e haverá flacidez precoce.

INTRODUCTION: The skin presents structural and proteomic changes after bariatric surgery and cannot withstand the weight of the breasts, which leads to early residual flaccidity, requiring auxiliary support. The goal is to apply a nonabsorbable polypropylene-poliglecaprone absorbable auxiliary mesh support or Bustos silicone sheet, in the form of an "internal brassiere," to support the skin in order to maintain the shape and flaccidity of the breasts comparable with those of normal breasts. METHODS: Nine patients underwent mammoplasty in inverted T with modeling of tissue implants, reduction of breast volume, and wrapping with an auxiliary support mesh. RESULTS: Flaccidity was not observed at an early stage and the condition was acceptable for up to 4 years of follow-up. One of the patients had a seroma, which was drained with good resolution. Another 24 patients will be operated according to the protocol and observed for 2 years by using mammography, ultrasonography, and magnetic resonance imaging. CONCLUSION: Reduction mammoplasty after bariatric surgery requires additional support for the mammary gland. The structurally altered skin could not support the weight of the breasts, resulting in early flaccidity.

Inflammatory reaction and tensile strength of the abdominal wall after an implant of polypropylene mesh and polypropylene/poliglecaprone mesh for abdominal wall defect treatment in rats

PURPOSE: To compare the inflammatory reaction and the growing resistance of the abdominal wall with the use of poliglecaprone meshes and polypropylene meshes associated with poliglecaprone in the correction of abdominal defects. METHODS: Seventy-seven Wistar rats were divided into three groups: CG (non-operated animals: EG (polypropylene mesh) and UG (polypropylene and poliglecaprone mesh). A muscular and aponeurotic defect was formed and treated according to the group. Evaluations were made after 4, 7, 14, 28 and 56 days. The resistance and inflammatory pattern were studied. RESULTS: There was a gradual and significant gain in resistance, regularly in the EG and irregularly in the UG, which was lower on the 14th day (p=0.008). The inflammatory reaction was acute and more intense in the UG on the fourth day. At all other times, the inflammatory pattern was acute to chronic, similar in both groups, with minimum intensity on the 56th day. CONCLUSION: The greater resistance offered by the polypropylene mesh was regular and ascending, stabilizing on the 28th day, while that of the polypropylene/poliglecaprone was not even. In the end, the resistances were similar. The inflammatory response was greater in the UG on the fourth day and similar at all other times. .

Utilização do Sistema Prolene de Hérnia (SPH) para o reparo de hérnias inguinais / Using the Prolene Hernia System (PHS) for inguinal hernia repair

OBJETIVO: Aferir complicações pós-operatórias imediatas e tardias em pacientes portadores de hérnia inguinal, submetidos à correção cirúrgica pela técnica de Gilbert1, com utilização do Sistema Prolene de Hérnia (SPH). MÉTODOS: Foram pesquisados todos os pacientes submetidos à herniorrafia inguinal com tela PHS no Hospital São Lucas da PUCRS no período de janeiro de 2001 até ourubro de 2006. As informações foram coletadas de modo retrospectivo, através de contato telefônico e revisão de prontuários. O protocolo de coleta de dados contemplou os aspectos epidemiológicos, bem como as complicações imediatas e tardias. RESULTADOS: Foram incluídos 96 pacientes. Foram identificadas seis (6,25 por cento) complicações, em pacientes distintos; nenhuma complicação com óbito. Dois pacientes (2,08 por cento) apresentaram seroma; hematoma foi identificado em um paciente (1,04 por cento); um paciente (1,04 por cento) apresentou infecção de ferida operatória. Dois pacientes (2,08 por cento) apresentaram edema escrotal. Após seguimento médio de 49,25 meses (16-86,12) dois pacientes (2,08 por cento) apresentaram dor crônica e um paciente (1,04 por cento) apresentou recorrência, com vinte e seis meses de pós-operatório. CONCLUSÃO: O reparo de hérnias inguinais com tela PHS é um método seguro, eficaz, facilmente reprodutível e com baixas taxas de complicações, recorrência ou sintomas em longo prazo.

OBJECTIVE: To assess immediate postoperative and late complications in patients with inguinal hernia undergoing surgical correction by Gilbert¹ technique, using the Prolene Hernia System (HPS). METHODS: We surveyed all patients undergoing inguinal hernia repair with PHS mesh at The Sao Lucas Hospital - PUCRS, from January 2001 to october 2006. Information was retrospectively collected through telephone calls and chart review. The protocol for data collection included epidemiological aspects, as well as immediate and late complications. RESULTS: ninety-six patients were enrolled. We identified six (6.25 percent) complications in different patients, none of which resulting in death. Two patients (2.08 percent) had seroma; hematoma was identified in one patient (1.04 percent); one patient (1.04 percent) had wound infection. Two patients (2.08 percent) had scrotal edema. After a mean follow up of 49.25 months (range 16 to 86.12) two patients (2.08 percent) had chronic pain and one patient (1.04 percent) had hernia recurrence twenty-six months after surgery. CONCLUSION: The repair of inguinal hernia with PHS is a safe, effective and reproducible method, with low complication and recurrence rates or long term symptoms.

Gross and histologic evaluation of abdominal adhesions associated with chromic catgut and polypropylene sutured enteropexies in dog / Evaluación macroscópica e histológica de las adherencias abdominales asociadas a enteropexias suturadas con catgut crómico y polipropileno en perros

The gross and histologic patterns of abdominal adhesions formed by the use of chromic catgut and polypropylene suture materials were evaluated in dogs. Gross and histologic examinations did not reveal significant difference (p>0.05) in the degree of adhesions observed at enteropexy sites in both suture materials. The use of polypropylene with superior suture qualities should be considered instead of chromic catgut for procedures in which adhesion is desired in the dog.

Fueron evaluados los patrones macroscópicos e histológicos de las adherencias abdominales formadas por el uso de catgut crómico y materiales de sutura de polipropileno. Los exámenes macroscópicos e histológicos no revelaron diferencias significativas (p> 0,05) en el grado de adherencias observadas en los sitios de la enteropexia en ambos materiales de sutura. El uso de suturas de polipropileno con mejores cualidades debe ser considerado en lugar del catgut cromado para procedimientos en los que la adherencia en el perro es deseada.

Evaluation of peritoneal adhesions formation and tissue response to polypropylene - poli (2-hydroxyethyl methacrylate)-(polyHEMA) implant on rats' abdominal wall / Avaliação da formação de aderências peritoneais e da resposta tecidual ao implante de poli (2-hidroxietil dimetacrilato)-(poliHEMA) na parede abdominal de ratos

PURPOSE: To verify if the composit poli (2-hydroxyethyl methacrylate)-PolyHEMA/polypropylene mesh implanted in the female rat's abdominal wall could be suitable for the prevention of peritoneal adhesions, and for the evaluation of the tecidual response produced by this biomaterial. METHODS: Polypropylene meshes (Group PP, n=20) and polypropylene meshes coated with a layer of poli (2-hydroxyethyl methacrylate)-PolyHEMA (Group PH, n=20) were implanted on the abdominal wall of Wistar female rats. Ten animals from each group were submitted to euthanasia at 15 and 30 days of the postoperative period. RESULTS: The animals from the group PP presented visceral adhesions on the mesh surface, which was not observed in the ones from group PH. At the histopathological examination foreign body response was observed in both groups, whilst there was a greater intensity of inflammatory response in group PH on both moments. CONCLUSION: The poli (2-hydroxyethyl methacrylate) polyHEMA hydrogel associated to polypropylene mesh reduces visceral adhesion formation in rats, although it may be associated to greater inflammatory reaction.

OBJETIVO: Verificar se compósito poli 2-hidroxietil dimetacrilato (PoliHEMA) / tela de polipropileno implantado na parede abdominal de ratas seria adequado para prevenção de aderências peritoneais e avaliar a resposta tecidual desencadeada por este biomaterial. MÉTODOS: Foram implantadas telas de polipropileno - Grupo PP (n=20) e telas de polipropileno revestidas por uma camada de poli 2 (hidroxietil dimetacrilato)-PolyHEMA - Grupo PH (n=20) na parede abdominal de ratas da linhagem Wistar. Dez animais de cada grupo foram submetidos à eutanásia aos 15 e 30 dias de pós-operatório. RESULTADOS: Os animais do grupo PP apresentaram aderências viscerais na superfície da tela, o que não foi observado nos do grupo PH. Observou-se no exame histopatológico resposta tipo corpo estranho nos dois grupos sendo que no grupo PH houve maior intensidade de resposta inflamatória nos dois momentos. CONCLUSÃO: O hidrogel de poliHEMA quando associado à tela de polipropileno reduz a formação de aderências viscerais em ratos, embora possa estar associado à reação inflamatória mais intensa.

Uso de 2-octil cianoacrilato em anastomose colônica: estudo experimental em ratos wistar / The use of 2-octyl cyanoacrylate in colonic anastomosis: experimental study in wistar rats

OBJETIVO: Comparar os resultados das anastomoses colônicas realizadas com o adesivo 2-octil cianoacrilato e as feitas com fio de polipropileno 5.0. MÉTODOS: Selecionaram-se 32 ratos Wistar machos distruibuidos em quatro grupos de oito animais tendo em conta o tipo de sutura - polipropileno ou aplicação de cianoacrilato -, e os dias para eutanásia - terceiro ou sétimo do pós-operatório. Nos animais dos grupos controle, as anastomoses foram realizadas em plano único com fio de polipropileno 5.0. Nos dos grupos com adesivo, elas foram executadas com 2-octil cianoacrilato. Avaliaram-se o tempo operatório, a integridade, o aspecto macroscópico das anastomoses, a pressão de ruptura à distensão, obstrução intestinal, formação de aderências e histologicamente o processo cicatricial e inflamatório. RESULTADOS: O tempo operatório foi significativamente maior nos grupos em que se aplicou adesivo tanto no terceiro quanto no sétimo dias (p=0,004). A formação de aderências foi mais extensa no grupo 2-octil cianoacrilato estudado no sétimo dia de pós-operatório em comparação com o grupo polipropileno (p=0,007). Os valores obtidos no estudo tensiométrico da anastomose, no sétimo dia de pós-operatório, mostraram-se menores no grupo 2-octil cianoacrilato (p=0,002). A frequência de obstrução intestinal parcial foi maior no grupo em que se aplicou adesivo quando avaliado no sétimo dia (0,029). O processo cicatricial e inflamatório não diferiu entre os grupos, seja no terceiro ou sétimo dias (p>0,05). CONCLUSÃO: Em condições experimentais, o uso do 2-octil cianoacrilato, avaliado no sétimo dia revelou-se deletério, levando a intensa formação de aderências, obstrução parcial da luz colônica, e menor resistência mecânica da anastomose.

OBJECTIVE: To compare the effect of 2-octyl cyanoacrylate tissue adhesive with polypropylene suture on the healing of colonic anastomosis in Wistar rats. METHODS: Thirty two animals, divided in four groups of eigth, were established concerning suture with Polypropylene or Cyanoacrylate application, and the day chose for euthanasia: third or seventh day following operation. In the control group, the anastomosis was done in a single layer with 5.0 polypropylene suture. In the adhesive group, the anastomosis was performed by using 2-octyl cyanoacrylate. Operative time, integrity and gross anastomotic healing, bursting pressure, intestinal obstruction, adhesions formation, histological healing and inflammatory process were recorded. RESULTS: Adhesion formation was more extensive in the cyanoacrylate group on the seventh postoperative day comparing with suture group (p=0.007). Mechanical strength of the anastomosis assessed on the seventh postoperative day was lower in 2-octyl cyanoacrylate group (p=0.002). Partial intestinal obstruction rate were more frequent in anastomosis using 2-octyl cyanoacrylate compared to those with polypropylene suture on the seventh postoperative day (p=0.029). Operative time were longer in groups with adhesive (p=0.004). The wound healing process, and inflammatory process did not differ statistically between groups (p>0.05). CONCLUSION: The application of 2-octyl cyanoacrylate, under experimental conditions seems to be detrimental at the seventh day of the healing, causing intense adhesion formation, colonic obstruction; and impairment healing with less mechanical strength resistance.

The optical analysis of the abdominal wall using the biospeckle after implants of polypropylene mesh in rats / Análise ótica da parede abdominal pelo biospeckle após implante de prótese de polipropileno em ratos

PURPOSE: To evaluate an experimental animal model to study the abdominal tissue activity considering its interaction with a polypropylene mesh, through the use of one of the optical phenomena of light Laser, the biospeckle. METHODS: Fifty Wistar male rats were divided into four groups: Group 1: ten animals not submitted to surgery; Group 2: ten animals submitted to surgery without polypropylene mesh; Group 3: 20 animals submitted to surgery followed by the mesh placement; Group 4: (sham) with ten animals. None of the animals presented post surgical complications being submitted to the optical tests at the 20th postoperative day. RESULTS: The analysis from the biospeckle tests, comparing the medians and standard deviations with T Student test, indicated that no significative difference was observed on the abdominal wall tissue activity in the four groups considered, with and without polypropylene mesh prosthesis implantation. CONCLUSION: The animal model is viable and the biospeckle open ways for a great number of experiments to be developed in evaluating tissue activity.

OBJETIVO: Avaliar o modelo experimental animal para o estudo da atividade tecidual da parede abdominal em sua interação com a prótese de polipropileno, através da utilização de um dos fenômenos ópticos da luz Laser, o biospeckle. MÉTODOS: Foram utilizados 50 ratos Wistar machos, divididos em quatro grupos: Grupo 1 com 10 animais não operados e controles; Grupo 2 com 10 animais submetidos a cirurgia sem a colocação de prótese; Grupo 3 com 20 animais submetidos a cirurgia com colocação de prótese de polipropileno pré-peritonial; Grupo 4 (Sham) com 10 animais. Nenhum animal apresentou complicações pós-operatórias, sendo que no 20º PO foram submetidos ao ensaio óptico. RESULTADOS: A comparação das médias e o desvio padrão das medidas da atividade tecidual da parede abdominal, com e sem implantação da prótese de polipropileno obtidas dos grupos de animais, pelo teste T de Student, não evidenciou diferença estatística significativa (p>0.05). CONCLUSÃO: A análise dos dados obtidos permitiu concluir que o modelo animal é viável e que o biospeckle abre caminhos para toda uma linha de experimentos a ser desenvolvida em avaliar atividade tecidual.

Polylactic acid film versus acellular porcine small intestinal submucosa mesh in peritoneal adhesion formation in rats / Filme ácido poli-lático versus tela de submucosa intestinal suína na formação de aderências peritoneais em ratos

PURPOSE: To assess intraperitoneal adhesion formation in rats after the single implantation of intraperitoneal polypropylene mesh versus SIS mesh, and the effect of PAF as a polypropylene mesh barrier. METHODS: A total of 55 albino rats randomized into three groups were assessed. The type of adhesions, the percentage of mash covered with adhesions, and the rupture strength of the adhesions were evaluated. RESULTS: The type 2 and 3 adhesions were more frequent in group 1 (polypropylene mesh) and group 3 (Polypropylene+PAF), while type 0 and 1 adhesions were more frequent in group 2 (SIS). The mean rupture strength was 1,58 N (±0,719N) in group 1, 0,42 N (±0,432N) in group 2 and 1,23 N (±0,432N) in group 3. Over 50% of the mash was covered with adhesions in 12 (80%) cases of the group 1, in 4 (20%) cases of the group 2 and in 16 (84,2%) cases of the group 3. Group 2 differed significantly (p<0.001) from the other groups. CONCLUSIONS: Implantation of intraperitoneal polypropylene mesh yielded higher rates of adhesion and the use of PAF as a mesh barrier didn't reduced the rates of adhesion. SIS mesh implantation revealed lower rates of peritoneal adhesions.

OBJETIVO: Avaliar a formação de aderência intraperitoneal em ratos após o implante peritoneal da tela de polipropileno comparada à tela de SIS, e o efeito do PAF como barreira anti-aderente à tela de polipropileno. MÉTODOS: 55 ratos albinos foram randomizados em três grupos. O tipo de aderência, o percentual de tela coberta por aderência, e a força de rupturas das aderências foram avaliadas. RESULTADOS: Os tipos de aderência 2 e 3 foram mais freqüentes no grupo 1 (polipropileno) e no grupo 3 (polipropileno+PAF); as do tipo 0 e 1 foram mais freqüentes no grupo 2 (SIS). A força media de ruptura foi de 1,58N (±0,719N) no grupo 1, 0,42N (±0,432N) no grupo 2 e 1,23N (±0,432N) no grupo3. Mais de 50% da tela estava coberta por aderências em 12 (80%) casos do grupo 1, em 4 (20%) casos do grupo 2 e em 16 (84,2%) casos do grupo 3. O grupo 2 foi significativamente diferente (p<0.001) dos outros grupos. CONCLUSÕES: O uso intraperitoneal da tela de polipropileno levou a elevados índices de aderência, e o uso de PAF como barreira anti-aderente não reduziu os índices de aderência. O implante intraperitoneal de SIS revelou índices baixos de aderências peritoneais.

Comparação entre a tela de submucosa intestinal suína acelular (Surgisis®) e a tela polipropileno (Marlex®) na formação de aderências peritoneais ­ estudo experimental em ratos / Comparison between the acelular porcine intestinal submucosa mesh (Surgisis®) and the polypropylene mesh (Marlex®) in the formation of peritonial adhesions ­ an experimental study in rats

Introdução: Comparar o índice de aderências intraperitoneais entre a tela de submucosa intestinal suína (Surgsis®) e tela polipropileno intraperitoneal (Marlex®) em modelo animal. Metodologia: Foram analisados três grupos de ratas albinas totalizando 40 animais grupo 0 (Sham operation sem tela) = 5 ratos, grupo 1 (tela de polipropileno) = 15 ratos, grupo 2 (tela de submucosa intestinal suína intraperitoneal) = 20 ratos. Estes foram anestesiados com xilasina (5mg/kg) e quetamina (50mg/kg) para a realização do procedimento. Após 21 dias, os animais foram mortos e avaliou-se o percentual de tela comprometida, o tipo de víscera envolvida, o tipo de aderência (graduado de 0 ­ ausência de aderências, a 3 ­ aderências firmes), bem como a força necessária para sua ruptura. Resultados: No grupo 1, todos os animais apresentaram aderências, sendo as aderências 2 e 3 os tipos mais freqüentes (86,6%). Em um animal houve aderência firme do intestino delgado. No grupo 2, foram encontradas aderências do tipo 0 e 1 em 75% dos animais; as do tipo 3 não foram encontradas. Quando comparados, os grupos diferiram estatisticamente (p<0,001) em todos os parâmetros avaliados. Conclusão: A tela de Marlex® apresentou índices elevados de aderências, o que pode representar uma maior possibilidade de complicações pós-operatórias (AU)

Introduction: To compare the rate of intraperitoneal adhesions between the porcine intestinal submucosa surgical mesh (Surgsis®) and intraperitoneal polypropylene mesh (Marlex®) in animal model. Methodology: A total of 40 albino female rats divided in three groups were analyzed: Group 0 (Sham operation without mesh) = 5 rats, Group 1 (polypropylene mesh) = 15 rats, and Group 2 (intraperitoneal intestinal submucosa mesh) = 20 rats. The animals were anesthetized with xylasine (5mg/kg) and ketamine (50mg/kg) prior to the procedure. After 21 days, the animals were killed and we evaluated the percentage of compromised mesh, the type of viscera involved, the type of adhesions (rated in a scale from 0 =absence of adhesions to 3 = firm adhesions), as well as the necessary force for their rupture. Results: All animals in Group 1 presented adhesions, types 2 and 3 being the most frequent ones (86.6%). One animal had firm adhesion of the small intestine. In Group 2, adhesions type 0 and 1 were found in 75% of the animals, and type 3 was not found. When the groups were compared, they were statistically different (p<0.001) in all the evaluated parameters. Conclusion: The Marlex® mesh presented higher rates of adhesion, which can increase the possibility of postoperative complications (AU)

Prospective study on the effects of a polypropylene prosthesis on testicular volume and arterial flow in patients undergoing surgical correction for inguinal hernia

PURPOSE: To evaluate testicular volume and arterial flow in patients undergoing surgical correction for inguinal hernia, with polypropylene prosthesis. METHODS: This was an observational prospective clinical study on 39 male patients with unilateral inguinal hernia of types III A and III B according to the Nyhus classification who underwent surgical correction with implantation of a polypropylene prosthesis by means of the Lichtenstein technique. The patients were evaluated using Doppler ultrasound before the operation and selectively at the third and sixth months after the operation. The variables studied were testicular volume, systolic and diastolic velocity, resistance index and pulsatility index. RESULTS: No statistically significant alterations in the variables studied were observed over the course of time: testicular volume (p= 0.197); systolic velocity (p= 0.257); diastolic velocity (p= 0.554); resistance index (p= 0.998); and pulsatility index (p= 0.582). CONCLUSION: No alteration in testicular volume and arterial flow over a six-month period was observed among patients who underwent surgical correction for inguinal hernia using a polypropylene prothesis.

OBJETIVO: Avaliar o volume testicular e o fluxo na artéria testicular em pacientes operados de inguinal com prótese de polipropileno. MÉTODOS: Estudo clínico prospectivo observacional em 39 pacientes do sexo masculino portadores de hérnia inguinal tipo III A e III B na classificação de Nyhus os quais foram submetidos a hernioplastia inguinal com implantação de prótese de polipropileno com a técnica de Lichtenstein. Os pacientes foram avaliados com ultra-sonografia Doppler no pré-operatório; no 3° mês e no 6° mês de pós-operatório. As variáveis estudadas foram: volume testicular; velocidade sistólica e diastólica, o índice de resistividade e o índice de pulsatilidade. RESULTADOS: Não se observou alterações estatisticamente significantes nas variáveis ao longo do tempo: volume testicular (p=0,197); velocidade sistólica (p=0,257); velocidade diastólica (p=0,554); índice de resistividade (p=0,998); índice de pulsatilidade (p=0,582). CONCLUSÃO: Não se observou alteração no volume testicular e no fluxo sanguíneo da artéria testicular após seis meses nos pacientes submetidos à correção cirúrgica de hérnia inguinal com prótese de polipropileno..

Experimental study comparing the tensile strength of different surgical meshes following aponeurotic-muscle deformity synthesis on Wistar rats

PURPOSE: To assess the tensile strength of polypropylene and polypropylene associated with polyglactin meshes (Vypro II® - Ethicon®, Somerville, NJ, USA) in a situation of partial separation of abdominal muscle aponeurosis on rats. METHODS: Thirty rats were used of the Wistar strain, which were randomized into two groups of 15 specimens each. In both groups an aponeurotic-muscle deformity was created on the abdominal wall measuring 3.0 x 1.0 cm, which was closed with polypropylene mesh (polypropylene group) or Vypro® mesh (vypro group). After 28 days the rats underwent euthanasia and an area was removed from the abdominal wall with which a strip was made measuring 2.0 cm in length and 6.0 cm in width comprising the abdominal muscles with the implanted mesh. This sample was placed in a mechanical test machine in which a constant force was applied contrary to the tissue strips. Maximum force expressed in Newton was considered until full rupture of the sample occurred. The non-parametric Kruskal - Wallis test was used for statistical analysis admitting p<0.05. RESULTS: Out of the thirty animals, there were two deaths in the vypro group and one unit in the polypropylene group was lost. One animal in the polypropylene group developed hernia during the study and another one developed granuloma of the abdominal wall. All animals in both groups developed epiplon adherence to the mesh. The average force was 48.08 N for the polypropylene group and 45.32 for the vypro® group. CONCLUSION: In these experimental conditions it could be observed that there is no statistically significant difference in the rupture force of the polypropylene and Vypro® meshes (p=0.54).

OBJETIVO: Avaliar a resistência tênsil das telas de polipropileno e polipropileno associado à poliglactina (Vypro II® - Ethicon®, Somerville, NJ, USA) em situação de afastamento parcial da aponeurose dos músculos abdominais em ratos. MÉTODOS: Foram utilizados trinta ratos da linhagem Wistar randomizados em dois grupos de quinze exemplares cada um. Em ambos os grupos criou-se um defeito músculo-aponeurótico na parede abdominal medindo 3,0 x 1,0 cm que foi fechado com tela de polipropileno (grupo polipropileno) ou Vypro® (grupo vypro). Após 28 dias, foi feita a eutanásia e retirou-se uma área da parede abdominal com a qual fez-se uma tira medindo 2,0 cm de comprimento por 6,0 cm de largura englobando os músculos abdominais com a tela implantada. Essa amostra foi presa em máquina de ensaios mecânicos na qual se aplicou força constante contrária às tiras de tecido. Foi considerada a força máxima expressa em Newton até ocorrer a ruptura total da amostra. Para a análise estatística, utilizou-se teste não paramétrico de Kruskal - Wallis admitindo-se p<0,05. RESULTADOS: Ocorreram dois óbitos do grupo vypro e uma unidade do grupo polipropileno foi perdida no teste mecânico. Um animal do grupo polipropileno desenvolveu hérnia durante o período do estudo e outro desenvolveu um granuloma de parede abdominal. Todos os animais de ambos os grupos desenvolveram aderência de epíplon à tela. A média das forças foi de 48.08 N para o grupo polipropileno e 45.32 N para o grupo vypro®. CONCLUSÃO: A tela de polipropileno apresentou uma força média de resistência à tração maior quando comparada com a de Vypro® nessas condições experimentais.

Comparative study of two surgical methods used for rectocele repair

The present study was carried out to evaluate traditional repair of rectocele [posteriorcolpoperineorrhaphy] versus prolene mesh repair of rectocele.The study was carried out on 40 patients divided into two equal group; [I] and [II]. This study wasconducted in Alexandria University Shatby Maternity hospital from May 2005 to April 2006 with an averagepostoperative follow up period of 6 months.It was found that mesh repair of rectocele is superior over the traditional posteriorcolpoperineorrhaphy. This new technique takes less operative time and complications, less post-operativecomplications and a better improvement of patient symptoms.mesh repair of rectocele is a safe technique with a reasonable success and accepted rate ofcomplications. However, more researches are needed to prove the success of this technique over a longerperiod of follow up. It is probable that no single technique can correct all rectoceles because of their diverseanatomic and functional components. Prolene mesh repair of rectocele has a favorable rate of symptomresolution with a low rate ofdenovo symptoms. The technique appears useful for properly informed patientswhose goals are reduced protrusion, improved defecation and avoidance of dyspareunia