Improved immediate postoperative pain following laparoscopic inguinal herniorrhaphy using self-adhering mesh.

BACKGROUND: Several synthetic meshes are available to reinforce the inguinal region following laparoscopic hernia reduction. We sought to compare postoperative pain of patients who underwent laparoscopic inguinal herniorrhaphy using self-adhering polyester mesh to those who had non-adhering, synthetic mesh implanted using absorbable tacks. MATERIALS AND METHODS: This study is a retrospective review of patients who underwent primary laparoscopic inguinal herniorrhaphy at the Medical College of Wisconsin between October 2012 and July 2014. Clinical information and perioperative pain scores using the visual analog scale (VAS) were obtained to evaluate immediate pre and postoperative pain. RESULTS: A total of 98 patients (88 male) underwent laparoscopic inguinal herniorrhaphy during the study interval. Forty-two patients received self-adhering mesh and 56 patients received mesh secured with tacks. Patient demographics and comorbidities did not differ significantly between the two groups. There was no difference in preoperative VAS scores between groups. The self-adhering mesh patients had a lower mean VAS change score (less pain). Postoperative complications did not differ between groups apart from a higher observed incidence of seroma in the self-adhering mesh group (p = 0.04). No hernias recurred in either group during the study interval. CONCLUSIONS: Self-adhering mesh in laparoscopic inguinal herniorrhaphy resulted in less immediate postoperative pain than tacked mesh as demonstrated by VAS score. Postoperative complications were similar between the two groups. The results of this study demonstrate that laparoscopic inguinal herniorrhaphy using self-adhering mesh is comparable to tacked mesh in regards to short-term complication rates, but show a favorable advantage in regards to immediate postoperative pain.

Acetazolamide reduces postoperative pain following laparoscopic inguinal herniorrhaphy.

BACKGROUND: Carbonic acid accumulation, which results from CO2 insufflation, can produce visceral and referred pain in the postoperative setting. Acetazolamide inhibits carbonic anhydrase, an enzyme that accelerates carbonic acid formation. We hypothesized that preoperative administration of acetazolamide would decrease postoperative pain in patients undergoing laparoscopic inguinal herniorrhaphy. METHODS: A retrospective review was conducted of patients who underwent laparoscopic preperitoneal inguinal herniorrhaphy at the Medical College of Wisconsin between October 2012 and September 2014. Beginning in January 2014, patients began receiving 250 mg of acetazolamide preoperatively; patients prior to that time did not. The visual analog scale (range 0-10) was used to assess both preoperative pain and postoperative pain. RESULTS: A total of 66 patients underwent laparoscopic inguinal herniorrhaphy during the study interval. Of these, 22 (33 %) patients received acetazolamide preoperatively, and 44 (67 %) were included as controls. Overall mean pain scores were lower in the acetazolamide group (1.9 ± 1.45 vs 2.9 ± 1.5, p = 0.04). Specifically, patients who received acetazolamide reported lower pain scores immediately after surgery (0.6 ± 1.2 vs 1.9 ± 2.3, p = 0.01) and on post-op day one (2.3 ± 0.9 vs 4.0 ± 2.1, p = 0.04). Total morphine equivalents administered to manage postoperative pain were significantly less for the acetazolamide group (4.3 ± 4.8 mg) when compared to the control group (8.9 ± 8.4 mg), p = 0.04. Perioperative complications did not differ between the groups (p = 0.16). CONCLUSIONS: Acetazolamide appears to reduce pain in the immediate postoperative setting. Patients who received acetazolamide had lower pain scores postoperatively and required fewer narcotics for pain management prior to discharge.

Curvature-processing network in macaque visual cortex.

Our visual environment abounds with curved features. Thus, the goal of understanding visual processing should include the processing of curved features. Using functional magnetic resonance imaging in behaving monkeys, we demonstrated a network of cortical areas selective for the processing of curved features. This network includes three distinct hierarchically organized regions within the ventral visual pathway: a posterior curvature-biased patch (PCP) located in the near-foveal representation of dorsal V4, a middle curvature-biased patch (MCP) located on the ventral lip of the posterior superior temporal sulcus (STS) in area TEO, and an anterior curvature-biased patch (ACP) located just below the STS in anterior area TE. Our results further indicate that the processing of curvature becomes increasingly complex from PCP to ACP. The proximity of the curvature-processing network to the well-known face-processing network suggests a possible functional link between them.