LigaSure hemorrhoidectomy versus the procedure for prolapse and hemorrhoids: A meta-analysis of randomized controlled trials.

BACKGROUND: LigaSure hemorrhoidectomy and the procedure for prolapse and hemorrhoids (PPH) are both relatively new treatments for managing symptomatic hemorrhoids. This review aimed to evaluate and compare their short-term outcomes. METHODS: We searched MEDLINE, EMBASE, the Cochrane Central Register of Controlled Trials and the China National Knowledge Infrastructure database for randomized controlled trials comparing the LigaSure procedure and PPH published in any language from 1998 to October 2013. RESULTS: A total of 5 studies involving 397 participants were included in this review. Pooled analysis showed that the LigaSure procedure was associated with significantly lower recurrence rate [relative risk (RR) = 0.21, 95% confidence interval (CI): 0.06 to 0.72, P = .01] and significantly shorter operating time [mean difference (MD) = -6.39, 95% CI: -7.68 to -5.10, P < .001]. The analysis showed no significant difference in postoperative pain between the two techniques (MD = 0.55, 95% CI: -0.15 to 1.25, P = .12] or in time off work or away from normal activity [standard MD = 0.13, 95% CI: -1.80 to 2.06, P = .9]. The two techniques did not show significant differences in postoperative complications or other patient-related outcomes (P > .05). CONCLUSIONS: Our review indicates that both LigaSure hemorrhoidectomy and PPH are safe alternatives for the management of hemorrhoids. Available evidence suggests that the LigaSure technique is associated with shorter operating time and lower hemorrhoid recurrence rate, but these conclusions should be further confirmed in large, multicenter randomized controlled trials with long-term follow-up.

Wave front aberrations induced from biomechanical effects after customized myopic laser refractive surgery in finite element model.

PURPOSE: A customized myopic refractive surgery was simulated by establishing a finite element model of the human eye, after which we studied the wave front aberrations induced by biomechanical effects and ablation profile after wave front-guided LASIK surgery. METHODS: Thirty myopia patients (i.e., 60 eyes) without other eye diseases were selected. Their ages, preoperative spherical equivalent, astigmatism, and wave front aberration were then obtained, in addition to the mean spherical equivalent error range - 4 to - 8D. Afterward, wave front-guided customized LASIK surgery was simulated by establishing a finite element eye model, followed by the analysis of the wave front aberrations induced by the surface displacement from corneal biomechanical effects, as well as customized ablation profile. Finally, the preoperative and induced aberrations were statistically analyzed. RESULTS: Comatic aberrations were the main wave front abnormality induced by biomechanical effects, and the wave front aberrations induced by the ablation profile mainly included coma and secondary coma, as well as sphere and secondary-sphere aberrations. Overall, the total high-order aberrations (tHOAs), total coma (C31), and sphere ([Formula: see text]) increased after wave front-guided customized LASIK surgery. According to our correlation analyses, coma, sphere, and tHOAs were significantly correlated with decentration. Additionally, the material parameters of ocular tissue were found to affect the postoperative wave front aberrations. When the material parameters of the sclera remained constant but those of cornea increased, the induced wave front aberrations were reduced. CONCLUSION: All biomechanical effects of cornea and ablation profile had significant effects on postoperative wave front aberrations after customized LASIK refractive surgery; however, the effects of the ablation profile were more notorious. Additionally, the characteristics of biomechanical materials have influence on the clinical correction effect.

Treatment and mechanism of fecal microbiota transplantation in mice with experimentally induced ulcerative colitis.

Restoring intestinal microbiota dysbiosis with fecal microbiota transplantation is considered as a promising treatment for ulcerative colitis. However, the mechanisms underlying its relieving effects remain unclear. Ulcerative colitis pathogenesis is associated with the involvement of immune cells and inflammatory cytokines. Here, we aimed to investigate the effect of fecal microbiota transplantation on T cell cytokines in a dextran sulfate sodium-induced ulcerative colitis mouse model. Five-aminosalicylic acid (5-ASA) was used as the positive control. Male C57BL/6 mice were randomly assigned to control, model (UC), UC + FMT, and UC + 5-ASA groups. Each group consisted of five mice. The establishment of the mouse model was verified by fecal occult-blood screening and hematoxylin-eosin staining. Results showed that fecal microbiota transplantation reduced colonic inflammation, significantly decreased T helper (Th)1 and Th17 cells, interferon-gamma, interleukin-2 and interleukin-17, as well as significantly increased Th2 and regulatory T (Treg) cells, interleukin-4, interleukin-10, and transforming growth factor-beta, and improved routine blood count. Furthermore, 16S rRNA gene-sequencing analysis showed a significant increase in the relative abundance of genus Akkermansia and a significant decrease in the relative abundance of genus Helicobacter in the ulcerative colitis group. Fecal microbiota transplantation restored the profile of the intestinal microbiota to that of the control group. These findings demonstrated the capability of fecal microbiota transplantation in controlling experimentally induced ulcerative colitis by improving Th1/Th2 and Th17/Treg imbalance through the regulation of intestinal microbiota.

Simulated biomechanical effect of aspheric transition zone ablation profiles after conventional hyperopia refractive surgery.

We studied the effects of the aspheric transition zone on the optical wavefront aberrations, corneal surface displacement, and stress induced by the biomechanical properties of the cornea after conventional laser in situ keratomileusis (LASIK) refractive surgery. The findings in this study can help improve visual quality after refractive surgery. Hyperopia correction in 1-5D was simulated using five types of aspheric transition zones with finite element modeling. The algorithm for the simulations was designed according to the optical path difference. Wavefront aberrations were calculated from the displacements on the anterior and posterior corneal surfaces. The vertex displacements and stress on the corneal surface were also evaluated. The results showed that the aspheric transition zone has an effect on the postoperative visual quality. The main wavefront aberrations on the anterior corneal surface are defocus, y-primary astigmatism, x-coma, and spherical aberrations. The wavefront aberrations on the corneal posterior surface were relatively small and vertex displacements on the posterior corneal surface were not significantly affected by the aspheric transition zone. Stress analysis revealed that the stress on the cutting edge of the anterior corneal surface decreased with the number of aspheric transition zone increased, and profile #1 resulted in the maximum stress. The stress on the posterior surface of the cornea was more concentrated in the central region and was less than that on the anterior corneal surface overall. The results showed that the aspheric transition zone has an effect on postoperative aberrations, but wavefront aberrations cannot be eliminated. In addition, the aspheric transition zone influences the postoperative biomechanical properties of the cornea, which significantly affect the postoperative visual quality.