Aberrometry Repeatability and Agreement with Autorefraction.

SIGNIFICANCE: Commercially available aberrometers are essential to clinical studies evaluating refractive error and image quality. The Discovery System (Innovative Visual Systems, Elmhurst, IL) is a promising clinical instrument that allows investigators to export aberration data for research and analysis purposes. An assessment of the Discovery System's performance is essential to the interpretation of the data obtained. PURPOSE: The aims of this study were to determine the between-visit repeatability of refractive error and higher-order aberration measurements with the Discovery System and to examine between-instrument agreement of refractive error measurements with the Discovery System and Grand Seiko WAM-5500 open-field autorefractor (Grand Seiko Co., Hiroshima, Japan). METHODS: Cycloplegic refractive error values from the Discovery System (over a 3-mm pupil) and the Grand Seiko autorefractor were converted to power vectors (M, J0, and J45), and averaged. Zernike coefficients were also calculated by the Discovery System over a 6-mm pupil through the sixth radial order. Between-visit repeatability and agreement were evaluated using Bland-Altman difference-versus-mean plots. A t-test compared each mean difference (bias) to zero, and the 95% limits of agreement were calculated. RESULTS: Twenty-five young adults with a mean (±SD) cycloplegic spherical-equivalent refractive error of -2.91 ± 1.85 diopters (D) (range, -6.96 to +0.74 D) were enrolled. There were no significant between-visit differences with the Discovery System for M, J0, J45, third- through sixth-order root mean square (RMS), higher-order RMS, or spherical aberration (all P > .30), and the repeatability for defocus and higher-order RMS were ±0.31 D and ±0.095 µm, respectively, for a 6-mm pupil. At a 3-mm pupil, the Discovery System, on average, measured slightly more positive values than the Grand Seiko for M (0.28 D), J0 (0.11 D), and J45 (0.12 D; all P < .005). CONCLUSIONS: The Discovery System was very repeatable and would be an appropriate instrument to measure cycloplegic refractive error and higher-order aberration changes in adults. Small differences in refractive error were found between the Discovery System and Grand Seiko.

A systematic review of randomized controlled trials and reviews in the management of ventral hernias.

BACKGROUND: The literature supporting ventral hernia management is growing; however, it is unclear whether the quality of work is improving. We hypothesize that the quality of clinical ventral hernia research has improved over the past 2.5 decades. METHODS: A review of MEDLINE, Scopus, and Cochrane databases was conducted for all ventral hernia studies from January 1, 1980 to May 1, 2015. Relevant abstracts were assigned a level according to the Oxford Center for Evidence-Based Medicine. Reviews, and meta-analyses were graded using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Checklist and randomized controlled trials (RCTs) using the Consolidated Standards of Reporting Trials (CONSORT) checklist. Studies that did not fulfill at least 70% of the elements for the PRISMA (19/27) or CONSORT (26/37) checklists were considered to contain substantial methodological flaws. RESULTS: Of 12,431 citations, 1336 met criteria for quality evaluation. Level 1 studies were sparse (n = 104, 7.8%), and most were level 2 or 3 (n = 463, 34.7%) or 4 (n = 769, 57.6%). Of the level 1 studies, 37 (35.6%) were RCTs, 61(58.7%) were reviews and/or meta-analyses, and 6 (5.8%) were consensus statements. Most RCTs and reviews and/or meta-analyses contained substantial methodological flaws (75.7%, 75.8%). Critical areas of weakness in RCTs were explaining losses and exclusions after randomization and/or allocation and reporting determination of sample size. For reviews and/or meta-analyses, areas of weakness were presenting an electronic search strategy and providing an assessment of risk of bias before pooling data. Linear regressions of PRISMA and CONSORT scores demonstrated improvement over time (PRISMA slope 0.95, R(2) = 0.24; CONSORT slope 0.34, R(2) = 0.08). CONCLUSIONS: Although the quality of literature guiding ventral hernia management has improved over time, there is room for improvement.

Mesh Location in Open Ventral Hernia Repair: A Systematic Review and Network Meta-analysis.

There is no consensus on the ideal location for mesh placement in open ventral hernia repair (OVHR). We aim to identify the mesh location associated with the lowest rate of recurrence following OVHR using a systematic review and meta-analysis. A search was performed for studies comparing at least two of four locations for mesh placement during OVHR (onlay, inlay, sublay, and underlay). Outcomes assessed were hernia recurrence and surgical site infection (SSI). Pairwise meta-analysis was performed to compare all direct treatment of mesh locations. A multiple treatment meta-analysis was performed to compare all mesh locations in the Bayesian framework. Sensitivity analyses were planned for the following: studies with a low risk of bias, incisional hernias, by hernia size, and by mesh type (synthetic or biologic). Twenty-one studies were identified (n = 5,891). Sublay placement of mesh was associated with the lowest risk for recurrence [OR 0.218 (95% CI 0.06-0.47)] and was the best of the four treatment modalities assessed [Prob (best) = 94.2%]. Sublay was also associated with the lowest risk for SSI [OR 0.449 (95% CI 0.12-1.16)] and was the best of the 4 treatment modalities assessed [Prob (best) = 77.3%]. When only assessing studies at low risk of bias, of incisional hernias, and using synthetic mesh, the probability that sublay had the lowest rate of recurrence and SSI was high. Sublay mesh location has lower complication rates than other mesh locations. While additional randomized controlled trials are needed to validate these findings, this network meta-analysis suggests the probability of sublay being the best location for mesh placement is high.

Preoperative Glycosylated Hemoglobin and Postoperative Glucose Together Predict Major Complications after Abdominal Surgery.

BACKGROUND: Glycosylated hemoglobin (HbA1c) is diagnostic of and a measure of the quality of control of diabetes mellitus. Both HbA1c and perioperative hyperglycemia have been targeted as modifiable risk factors for postoperative complications. The HbA1c percent cutoff that best predicts major complications has not been defined. STUDY DESIGN: A prospective study of all abdominal operations from a single institution from 2007 to 2010 was performed. All patients with HbA1c within 3 months before surgery were included. The primary end point was major complication, using the Clavien-Dindo complication system, within 30 days of surgery. Stepwise, multivariate analysis was performed including clinically relevant variables chosen a priori. RESULTS: Among 438 patients who had a measured HbA1c, 96 (21.9%) experienced a major complication. On multivariate analysis, HbA1c ≥ 6.5% (odds ratio = 1.95; 95% CI, 1.17-3.24; p = 0.01) was found to be the most significant predictor of major complications. Glyosylated hemoglobin and glucose were strongly correlated (correlation coefficient 0.414, p < 0.01). Predicted probabilities demonstrated that both HbA1c and glucose together contributed to major complications; and HbA1c impacted the ability to achieve optimal perioperative glucose control. Patients with a BMI >30 kg/m(2), history of coronary artery disease, and nonwhite race were more likely to have a HbA1c ≥ 6.5%. CONCLUSIONS: Elevated HbA1c ≥ 6.5% and perioperative hyperglycemia were associated with an increased rate of major complications after abdominal surgery. Elevated peak postoperative glucose levels were correlated with elevated HbA1c and were independently associated with major complications. More liberal HbA1c testing should be considered in high-risk patients before elective surgery. Safe, feasible, and effective strategies to reduce both HbA1c and perioperative hyperglycemia need to be developed to optimize patient outcomes.

Development and validation of a risk stratification score for ventral incisional hernia after abdominal surgery: hernia expectation rates in intra-abdominal surgery (the HERNIA Project).

BACKGROUND: Ventral incisional hernias (VIH) develop in up to 20% of patients after abdominal surgery. No widely applicable preoperative risk-assessment tool exists. We aimed to develop and validate a risk-assessment tool to predict VIH after abdominal surgery. STUDY DESIGN: A prospective study of all patients undergoing abdominal surgery was conducted at a single institution from 2008 to 2010. Variables were defined in accordance with the National Surgical Quality Improvement Project, and VIH was determined through clinical and radiographic evaluation. A multivariate Cox proportional hazard model was built from a development cohort (2008 to 2009) to identify predictors of VIH. The HERNIAscore was created by converting the hazards ratios (HR) to points. The predictive accuracy was assessed on the validation cohort (2010) using a receiver operator characteristic curve and calculating the area under the curve (AUC). RESULTS: Of 625 patients followed for a median of 41 months (range 0.3 to 64 months), 93 (13.9%) developed a VIH. The training cohort (n = 428, VIH = 70, 16.4%) identified 4 independent predictors: laparotomy (HR 4.77, 95% CI 2.61 to 8.70) or hand-assisted laparoscopy (HAL, HR 4.00, 95% CI 2.08 to 7.70), COPD (HR 2.35; 95% CI 1.44 to 3.83), and BMI ≥ 25 kg/m(2) (HR1.74; 95% CI 1.04 to 2.91). Factors that were not predictive included age, sex, American Society of Anesthesiologists (ASA) score, albumin, immunosuppression, previous surgery, and suture material or technique. The predictive score had an AUC = 0.77 (95% CI 0.68 to 0.86) using the validation cohort (n = 197, VIH = 23, 11.6%). Using the HERNIAscore: HERNIAscore = 4(∗)Laparotomy+3(∗)HAL+1(∗)COPD+1(∗) BMI ≥ 25, 3 classes stratified the risk of VIH: class I (0 to 3 points),5.2%; class II (4 to 5 points),19.6%; and class III (6 points), 55.0%. CONCLUSIONS: The HERNIAscore accurately identifies patients at increased risk for VIH. Although external validation is needed, this provides a starting point to counsel patients and guide clinical decisions. Increasing the use of laparoscopy, weight-loss programs, community smoking prevention programs, and incisional reinforcement may help reduce rates of VIH.

Laparoscopic repair reduces incidence of surgical site infections for all ventral hernias.

BACKGROUND: The role of laparoscopic repair of ventral hernias remains incompletely defined. We hypothesize that laparoscopy, compared to open repair with mesh, decreases surgical site infection (SSI) for all ventral hernia types. METHODS: MEDLINE, EMBASE, and Cochrane databases were reviewed to identify studies evaluating outcomes of laparoscopic versus open repair with mesh of ventral hernias and divided into groups (primary or incisional). Studies with high risk of bias were excluded. Primary outcomes of interest were recurrence and SSI. Fixed effects model was used unless significant heterogeneity, assessed with the Higgins I square (I(2)), was encountered. RESULTS: There were 5 and 15 studies for primary and incisional cohorts. No difference was seen in recurrence between laparoscopic and open repair in the two hernia groups. SSI was more common with open repair in both hernia groups: primary (OR 4.17, 95%CI [2.03-8.55]) and incisional (OR 5.16, 95%CI [2.79-9.57]). CONCLUSIONS: Laparoscopic repair, compared to open repair with mesh, decreases rates of SSI in all types of ventral hernias with no difference in recurrence. These data suggest that laparoscopic approach may be the treatment of choice for all types of ventral hernias.

Abdominal reoperation and mesh explantation following open ventral hernia repair with mesh.

BACKGROUND: This study sought to identify the incidence, indications, and predictors of abdominal reoperation and mesh explantation following open ventral hernia repair with mesh (OVHR). METHODS: A retrospective cohort study of all patients at a single institution who underwent an OVHR from 2000 to 2010 was performed. Patients who required subsequent abdominal reoperation or mesh explantation were compared with those who did not. Reasons for reoperation were recorded. The 2 groups were compared using univariate and multivariate analysis (MVA). RESULTS: A total of 407 patients were followed for a median (range) of 57 (1 to 143) months. Subsequent abdominal reoperation was required in 69 (17%) patients. The most common reasons for reoperation were recurrence and surgical site infection. Only the number of prior abdominal surgeries was associated with abdominal reoperation on MVA. Twenty-eight patients (6.9%) underwent subsequent mesh explantation. Only the Ventral Hernia Working Group grade was associated with mesh explantation on MVA. CONCLUSIONS: Abdominal reoperation and mesh explantation following OVHR are common. Overwhelmingly, surgical complications are themost common causes for reoperation and mesh explantation.

Primary fascial closure with laparoscopic ventral hernia repair: systematic review.

Laparoscopic ventral hernia repair (LVHR) has grown in popularity. Typically, this procedure is performed with a mesh bridge technique that results in high rates of seroma, eventration (bulging), and patient dissatisfaction. In an effort to avoid these complications, there is growing interest in the role of laparoscopic primary fascial closure with intraperitoneal mesh placement. This systematic review evaluated the outcomes of closure of the central defect during LVHR. A literature search of PubMed, Cochrane databases, and Embase was conducted using PRISMA guidelines. MINORS was used to assess the methodologic quality. Primary outcome was hernia recurrence. Secondary outcomes were surgical-site infection, seroma formation, bulging, and patient-centered items (satisfaction, chronic pain, functional status). Eleven studies were identified, eight of which were case series (level 4 data). Three comparative studies examined the difference between closure and nonclosure of the fascial defect during laparoscopic ventral incisional hernia repairs (level 3 and 4 data). These studies suggested that primary fascial closure (n = 138) compared to nonclosure (n = 255) resulted in lower recurrence rates (0-5.7 vs. 4.8-16.7 %) and seroma formation rates (5.6-11.4 vs. 4.3-27.8 %). Follow-up periods for both groups were similar (1-108 months). Only one study evaluated patient function and clinical bulging. It showed better outcomes with primary fascial closure. Closure of the central defect during LVHR resulted in less recurrence, bulging, and seroma than nonclosure. Patients with closure were more satisfied with the results and had better functional status. The quality of the data was poor, however. A randomized controlled trial to evaluate the role of closure of the central defect during LVHR is warranted.

Review of stoma site and midline incisional hernias after stoma reversal.

BACKGROUND: The incidence of incisional hernias after stoma reversal is not well reported. The aim of this study was to systematically review the literature reporting data on incisional hernias after stoma reversal. We evaluated both the incidence of stoma site and midline incisional hernias. METHODS: A systematic review identified studies published between January 1, 1980, and December 31, 2012, reporting the incidence of incisional hernia after stoma reversal at either the stoma site or at the midline incision (in cases requiring laparotomy). Pediatric studies were excluded. Assessment of risk of bias, detection method, and essential study-specific characteristics (follow-up duration, stoma type, age, body mass index, and so forth) was done. RESULTS: Sixteen studies were included in the analysis; 1613 patients had 1613 stomas formed. Fifteen studies assessed stoma site hernias and five studies assessed midline incisional hernias. The median (range) incidence of stoma site incisional hernias was 8.3% (range 0%-33.9%) and for midline incisional hernias was 44.1% (range 8.7%-58.1%). When evaluating only studies with a low risk of bias, the incidence for stoma site incisional hernias is closer to one in three and for midline incisional hernias is closer to one in two. CONCLUSION: Stoma site and midline incisional hernias are significant clinical complications of stoma reversals. The quality of studies available is poor and heterogeneous. Future prospective randomized controlled trials or observational studies with standardized follow-up and outcome definitions/measurements are needed.

Comparison of outcomes of synthetic mesh vs suture repair of elective primary ventral herniorrhaphy: a systematic review and meta-analysis.

IMPORTANCE: More than 350,000 ventral hernias are repaired in the United States annually, of which 75% are primary ventral hernias (eg, umbilical or epigastric hernias). Despite the volume, there is insufficient evidence to support the use of sutures vs mesh for primary ventral hernia repairs. OBJECTIVE: To compare suture vs mesh repairs for 3 outcomes: hernia recurrence, surgical site infection (SSI), and seromas. DATA SOURCES: Randomized controlled trials, case-control, and cohort studies were identified from OVID, PubMed, and reference lists from January 1, 1980, through June 1, 2012. STUDY SELECTION: English-language studies with adult patients were eligible for review if there was mention of both suture and mesh techniques used during elective repair of a primary ventral hernia. Two study authors independently reviewed the 1492 articles originally identified and selected 9 for analysis. The Downs and Black 26-item checklist was used to critically assess the risk of bias. DATA EXTRACTION: Year of publication, study design, inclusion and exclusion criteria, number of patients, follow-up duration, use of preoperative antibiotics, size of hernias repaired, age, body mass index (calculated as weight in kilograms divided by height in meters squared), American Society of Anesthesiologists grade, repair techniques, incidence of hernia recurrence, seroma, and SSI. DATA EXTRACTION AND SYNTHESIS: Three separate univariate meta-analyses for each end point followed by a multivariate meta-analysis were performed. Across all 9 studies, there were 637 mesh repairs and 1145 suture repairs. The pooled mesh repairs demonstrated a 2.7% recurrence rate, 7.7% seroma rate, and 7.3% SSI rate The pooled suture repairs demonstrated an 8.2% recurrence rate, 3.8% seroma rate, and 6.6% SSI rate. On the basis of results from the multivariate meta-analysis, recurrences (log odds ratio , −1.04; 95% CI, −1.58 to −0.52) were more common with suture repair, whereas seromas (0.84; 0.27-1.41) and SSIs (0.65; 0.12-1.18) were more common with mesh repair. CONCLUSIONS AND RELEVANCE: Mesh repair has a small reduction in recurrence rates compared with suture repairs for primary ventral hernias, but an increased risk of seroma and SSI was observed. Further high-quality studies are necessary to determine whether suture or mesh repair leads to improved outcomes for primary ventral hernias.

Readmission following open ventral hernia repair: incidence, indications, and predictors.

BACKGROUND: The aim of this study was to evaluate the incidence, indications, and predictive factors of hospital readmission after open ventral hernia repair. METHODS: A retrospective review of all open ventral hernia repairs at a single institution from 2000 to 2010 was performed to assess readmissions between 1 to 30, 1 to 90, and 91 to 365 days. Multivariate analysis was performed to identify independent predictors of 30-day readmission. RESULTS: Of the 888 patients, 75 (8%) were readmitted between 1 and 30 days, 97 (11%) between 1 and 90 days, and 78 (9%) between 91 and 365 days. Unplanned readmissions related to the surgery constituted the majority of 1-day to 30-day and 1-day to 90-day readmissions (82% and 74%, respectively) but not between 91 and 365 days (32%). Prior superficial or deep surgical-site infection (odds ratio, 2.39; 95% confidence interval, 1.32 to 4.32) and duration of surgery (odds ratio, 1.35; 95% confidence interval, 1.05 to 1.73) were associated with 30-day readmission. CONCLUSIONS: Efforts to reduce readmissions should be directed at modifiable risk factors for surgical-site infection and other surgical complications, particularly among those with prior skin infections and longer durations of surgery.