Page 221 - Prevention and Treatment of Incisional Hernia- New Techniques and Materials

Surgisis (p = 0.007). Organs were attached (Zühlke 4) to Permacol in 6 of 10 cases (60 %) and to Strattice in 2 of 10 cases (20 %). At 90 days, the Zühlke score of Permacol was signi cantly higher than the score of Parietex composite, Surgisis, or Strattice. No organs were attached to any of the meshes except Permacol (4 of 7, 57.1 %). The Zühlke scores for the Strattice (1; IQR, 1–2) and Surgisis (1; IQR, 0–1) meshes were signi cantly lower than for Prolene (2; IQR, 2–2).
Correlation between adhesion formation and incorporation
At 30 days, Strattice showed a signi cant correlation between adhesion coverage of the mesh and incorporation of the mesh edge (ρ = 0.681; p = 0.030). At 90 days, only Surgisis showed a signi cant correlation coe cient (ρ = 0.828; p = 0.021). In both cases, the correlation coe cient indicated that an increase of incorporation was correlated with an increase in adhesion formation.
Tissue reaction
At 30 days, histologic evaluation after H&E staining of the meshes demonstrated a grade 1 (mild) foreign body reaction to all the meshes except Permacol. This mesh showed a grade 2 in ammatory reaction, resulting in a thick brous layer between the mesh and the abdominal wall. Additionally, in some cases, a brous layer was visible on the abdominal side of the mesh, generally combined with strong adhesions (Figure 5).
At 90 days, a grade 1 mild foreign body reaction was visible around all the meshes, with limited numbers of giant cells and lymphocytes present. Parietex composite meshes showed a larger in ux of broblasts. Strattice and Parietex composite showed a new mesothelial layer on the visceral side of the mesh. On the Permacol mesh, a new mesothelial layer was alternating with a small layer of brous tissue.
Histologic samples after picrosirius red staining at 90 days are shown in Figure 6 Tissue surrounding the Prolene mesh indicates complete incorporation of the mesh by a layer of collagen around the Prolene bers. All these collagen bers have the same orientation and thickness. The collagen layer between mesh and muscles also was highly organized but in a di erent direction and with a di erent thickness because it is mostly of the same color.
In the case of Parietex composite, the mesh was completely covered with collagen in di erent orientations. The collagen directly surrounding the bers has a di erent direction than the collagen of the layer between the
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Biological mesh in hernia repair
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