Detection of abdominal wall adhesions using visceral slide

Quantifiable Measures of Abdominal Wall Motion for Quality Assessment of Cine-MRI Slices in Detection of Abdominal Adhesions

Abdominal adhesions present a diagnostic challenge, and classic imaging modalities can miss their presence. Cine-MRI, which records visceral sliding during patient-controlled breathing, has proven useful in detecting and mapping adhesions. However, patient movements can affect the accuracy of these images, despite there being no standardized algorithm for defining sufficiently high-quality images. This study aims to develop a biomarker for patient movements and determine which patient-related factors influence movement during cine-MRI. Included patients underwent cine-MRI to detect adhesions for chronic abdominal complaints, data were collected from electronic patient files and radiologic reports. Ninety slices of cine-MRI were assessed for quality, using a five-point scale to quantify amplitude, frequency, and slope, from which an image-processing algorithm was developed. The biomarkers closely correlated with qualitative assessments, with an amplitude of 6.5 mm used to distinguish between sufficient and insufficient-quality slices. In multivariable analysis, the amplitude of movement was influenced by age, sex, length, and the presence of a stoma. Unfortunately, no factor was changeable. Strategies for mitigating their impact may be challenging. This study highlights the utility of the developed biomarker in evaluating image quality and providing useful feedback for clinicians. Future studies could improve diagnostic quality by implementing automated quality criteria during cine-MRI.

An Overview of Postoperative Intraabdominal Adhesions and Their Role on Female Infertility: A Narrative Review

Postoperative intraabdominal adhesions can occur after more than 90% of gynecologic surgeries. They not only cause chronic pelvic pain and small bowel obstruction, but are also one of the main reasons for infertility. Adhesions are not only a burden for the affected patients, but are also a burden for the healthcare system, since the treatment of adhesion-associated complications costs a considerable amount of money. The gold standard for the diagnosis of adhesions is by laparoscopy, although other methods, such as transvaginal hydro-laparoscopy, are being discussed as better alternatives. Ideally, adhesions are avoided inherently, by operating carefully and by using microsurgical principles. If this is not possible, gel barriers have been shown to be successful in reducing postoperative adhesions.

Inter- and Intra-Observer Variability and the Effect of Experience in Cine-MRI for Adhesion Detection

Cine-MRI for adhesion detection is a promising novel modality that can help the large group of patients developing pain after abdominal surgery. Few studies into its diagnostic accuracy are available, and none address observer variability. This retrospective study explores the inter- and intra-observer variability, diagnostic accuracy, and the effect of experience. A total of 15 observers with a variety of experience reviewed 61 sagittal cine-MRI slices, placing box annotations with a confidence score at locations suspect for adhesions. Five observers reviewed the slices again one year later. Inter- and intra-observer variability are quantified using Fleiss’ (inter) and Cohen’s (intra) κ and percentage agreement. Diagnostic accuracy is quantified with receiver operating characteristic (ROC) analysis based on a consensus standard. Inter-observer Fleiss’ κ values range from 0.04 to 0.34, showing poor to fair agreement. High general and cine-MRI experience led to significantly (p < 0.001) better agreement among observers. The intra-observer results show Cohen’s κ values between 0.37 and 0.53 for all observers, except one with a low κ of −0.11. Group AUC scores lie between 0.66 and 0.72, with individual observers reaching 0.78. This study confirms that cine-MRI can diagnose adhesions, with respect to a radiologist consensus panel and shows that experience improves reading cine-MRI. Observers without specific experience adapt to this modality quickly after a short online tutorial. Observer agreement is fair at best and area under the receiver operating characteristic curve (AUC) scores leave room for improvement. Consistently interpreting this novel modality needs further research, for instance, by developing reporting guidelines or artificial intelligence-based methods.

Collagen Type-I Agent Reduced Postoperative Bowel Adhesions Following Laparoscopic and Robot-Assisted Radical Prostatectomy: A Prospective, Single-Blind Randomized Clinical Trial

This study aimed to compare the anti-adhesive effect of collagen type-I (COL) agent and hyaluronic acid-carboxymethylcellulose (HA/CMC) following laparoscopic and robotic radical prostatectomies. This study was a randomized, controlled, single-blind, multicenter study using COL and HA/CMC in patients who underwent laparoscopic and robotic radical prostatectomies. All patients were randomly assigned to either the COL (n = 66) or HA/CMC (n = 65) group. Viscera slide ultrasound sonography was recorded on the day of surgery (V2) and 12 weeks later (V4). The primary end point was the difference in the excursion distance in the viscera slide ultrasonography between V2 and V4. A total of 131 patients participated in this study. The viscera slide distance in the test and control groups was 1.89 ± 0.49 cm and 1.80 ± 0.45 cm, respectively, at V2 (p = 0.275). The average distance of the viscera slide in the test and control group was 1.59 ± 0.49 cm and 1.64 ± 0.45 cm, respectively at V4 (p = 0.614). None of the patients showed significant adverse effects. This randomized study showed that the efficacy and stability of the gel-type COL anti-adhesion agent are not inferior to those of HA/CMC, of which the properties are established.

The Underrated Role of Ultrasound in Peritoneal Dialysis

Ultrasound is very effective in performing procedures and assessment of complications in peritoneal dialysis. The ultrasound examination can be applied for preoperative assessment, during the peritoneal catheter placement, for the detection and monitoring of infection, as well as for the evaluation of the catheter malfunction. Despite being not only a cost- and time-saving technique but also a bedside procedure, ultrasonography remains an underrated clinical tool in the field of peritoneal dialysis. This publication wants to explain and reinforce the clinical utility of US in PD and to expand the diagnostic equipment for the clinician.

Ultrasound Visceral Slide Assessment to Evaluate for Intra-abdominal Adhesions in Patients Undergoing Abdominal Surgery - A Systematic Review and Meta-analysis

OBJECTIVE

Abdominal entry at the time of laparoscopy is a critical step with a risk of injury to underlying viscera owing to bowel adhesions. Ultrasound can be used as a preoperative tool to assess the slide of viscera underneath the abdominal wall to detect adhesion-free areas. The objective of this systematic review and meta-analysis was to determine the diagnostic accuracy of preoperative visceral slide assessment with ultrasound to detect intra-abdominal adhesions, compared with the gold standard of intraoperative findings.

DATA SOURCES

Using Cochrane, Medline PubMed, Embase, and Google Scholar electronic databases, 3737 articles were screened in April 2020 using a query that included variations of "adhesions" and "ultrasound." Reference lists of relevant articles were searched for further articles.

METHODS OF STUDY SELECTION

Prospective and cross-sectional studies in English that included patients at risk for intra-abdominal adhesions who underwent preoperative ultrasound visceral slide assessment and subsequent intraoperative assessment of adhesions were selected. Two reviewers independently selected 25 articles, extracted data, and assessed bias using the Quality Assessment of Diagnostic Accuracy Studies-2 tool.

TABULATION, INTEGRATION, AND RESULTS

Twenty-five articles reported on 1609 patients and 5812 assessed abdominal areas, with considerable heterogeneity of described abdominal areas and degrees of adhesions. Meta-analysis was performed for 21 studies. The periumbilical area was assessed specifically for bowel adhesions in 890 patients in 12 studies, with a 12.0% bowel adhesion rate. Ultrasound assessment for periumbilical bowel adhesions had a combined sensitivity of 95.9% (95% confidence interval, 82.7%-99.1%), specificity of 93.1% (85.1%-96.9%), positive predictive value of 60.4% (44.2%-74.7%), and negative predictive value of 99.2% (97.9%-99.7%) with low heterogeneity (I² = 16%).

CONCLUSION

Visceral slide assessment with ultrasound has a high negative predictive value for the absence of periumbilical bowel adhesions in patients at risk for adhesions and can function as a useful tool to detect adhesion-free areas to allow for safe laparoscopic entry.

Does applied ultrasound prior to laparoscopy predict the existence of intra-abdominal adhesions?

Background/aim

The purpose of this study was to evaluate the efficacy of trans-abdominal ultrasonography (USG), a noninvasive diagnostic tool, in predicting the presence of intraabdominal adhesions, especially near the trocar entry area, to provide safe surgical access to the abdomen.

Materials and methods

Fifty-nine women with a previous history of open abdominal surgery (group A) and a group of 91 women with no previous history of surgery (group B) underwent dynamic ultrasound evaluation of the abdominal fields before laparoscopic operations. The anterior abdominal wall was divided into six quadrants: right upper, right lower, left upper, left lower, suprapubic, and umbilical. Adhesions were evaluated by surgeons during the operation and by radiologists using USG prior to the operation. Visceral organ movements greater than 1 cm was defined as normal visceral slide (positive test), with less than 1 cm of movement defined as abnormal visceral slide (negative test). Sliding test measures movements of omental echogenicity or a stable echogenic focus that corresponds to intestine peritoneal echogenicity that underlies abdominal wall during exaggerated inspiration and expiration. Adhesions observed during surgery were evaluated on a four-point scale, with 0 indicating no adhesions present, 1 indicating the presence of a thin, filmy avascular adhesion, 2 indicating the presence of a dense and vascular adhesion, and 3 indicating adhesions that connect surrounding organs with the overlying peritoneal surfaces. The McNemar test was used to compare the results of USG and laparoscopy for each measure.

Results

We found that preoperative USG was successful in identifying adhesions [sensitivity, 96.39% (95% CI 89.8–99.2); specificity, 97.43%]

Conclusion

Preoperative ultrasound examination of the abdominal wall may enhance the safety of abdominal entry during laparoscopic operations.

Assessment of the diagnostic efficacy of abdominal ultrasonography and cine magnetic resonance imaging in detecting abdominal adhesions: A double-blind research study

PURPOSE

This cohort aimed to determine the efficacy and safety of abdominal ulrasonography and cine-MRI by a double-blind study in the diagnosis of intraabdominal organs and abdominal wall adhesions in patients with previous abdominal operations.

METHODS

Between 2017 and 2019, 108 consecutive patients were prospectively included in the study. Visceral slide and induced visceral slide were measured during AU and cine-MRI. An abdominal map consisting of nine segments was created to document the location and extent of the adhesion. The degree and severity of the adhesions detected by the radiologist preoperatively and detected in surgery as the gold standard was recorded in the same abdominal zones. AU, c-MRI and intraoperative findings were correlated.

RESULTS

The mean age was 53.0 ± 10.3 years, body mass index was 30.4 ± 3.4, male (52.8 %) and female (47.2 %). According to the total nine zones, the sensitivity of AU was 91.4 %, specificity was 100 %, positive predictive value was 90.7 %, negative predictive value was 100 % and diagnostic accuracy was 87.9 %. Considering the total zones, the sensitivity of c-MRI was 90.8 %, specificity was 100 %, PPV was 90.7 %, NPV was 100 % and diagnostic accuracy was 91.7 %. A comparison of AU and c-MRI showed no significant difference in the detection of adhesions to the abdominal wall; however, c-MRI was superior in detecting intraabdominal organs adhesion.

CONCLUSION

We have demonstrated that AU and c-MRI are accurate for diagnosing adhesions in patients undergoing repeated surgery and may have a place on planning elective laparoscopic or open surgery to avoid bowel injury.

The role of non-invasive imaging techniques in detecting intra-abdominal adhesions: a systematic review

BACKGROUND

Intra-abdominal adhesions after surgery are highly prevalent. Adhesions implicate complications during subsequent surgery and can cause chronic abdominal pain. The objective of this review was to investigate the usefulness of non-invasive diagnostic methods for detection of adhesions.

METHODS

We searched the electronic databases: MEDLINE, Embase, and The Cochrane Central Register of Controlled Trials for studies investigating the use of non-invasive diagnostic imaging techniques for detecting adhesions. Main outcome was the sensitivity and specificity of each technique. We used the Quality Assessment of Diagnostic Accuracy studies tool to assess bias.

RESULTS

In total, 25 studies were included: 18 using ultrasound (US), 5 using magnetic resonance imaging (MRI), 1 using computed tomography (CT), and 1 using both US and MRI. A total of 2195 patients were included. Overall accuracy ranged between 76 and 100% for US studies and between 79 and 90% for MRI and was 66% for CT. Sensitivity ranged between 21 and 100% for US and between 22 and 93% for MRI and was 61% for CT. Specificity was 32-100% for US, 25-93% for MRI, and 63% for CT. Bias analysis revealed that in most studies, investigators were blinded to the reference standard but not to the index test and 11 of 25 studies had a high risk of selection bias.

CONCLUSIONS

Currently, abdominal US can be used to determine the presence of adhesions between bowel and the abdominal wall. MRI is also an accurate diagnostic modality and can in addition visualize adhesions between viscera, however, with a tendency to over diagnose adhesions. There is insufficient evidence to support CT as a diagnostic modality for adhesions.

Prediction of pelvic adhesions at repeat cesarean delivery through assessment of striae gravidarum score: A cross-sectional study

OBJECTIVE

To investigate the predictive value of the Davey Score for striae gravidarum (SG) on the presence of pelvic adhesions at repeat cesarean delivery (CD).

MATERIALS AND METHODS

The current study was a cross-sectional study conducted in a tertiary university hospital between November 2016 and March 2018. All women scheduled for elective CD were included if they had at least previous one CD with pregnancy in term fetus (37-40 weeks gestation. Preoperative evaluation of SG severity using Davey score, which is a validated scoring system, was done on the examination bed. Patients with no/mild striae (score 0-2) were classified as group (I) and women with severe striae (score 3-8) were classified as group (II). During surgery, pelvic adhesions were evaluated and classified according to the Nair's scoring system. The primary outcome was the difference in the rate of pelvic adhesions between both groups.

RESULTS

The study included 300 women; group I included 114 women and group II included 186 women. About 90% of women with severe striae versus 82.5% of women with no/mild striae were found to have adhesions (p = 0.035). Dense adhesions were significantly present in severe striae group (57.4%) versus (41.5%) in no/mild striae group (p = 0.022). The mean Davey score in women in group (II) was significantly higher than group (I) (4.25 ± 3.36 vs. 3.09 ± 2.95, p = 0.03). Nair's score had a significant positive moderate correlation with Davey score (r = 0.541, p = 0.016). According to the results of multivariate regression analysis, Davey score >2 was the only variable associated with increased risk of pelvic adhesions (p = 0.010).

CONCLUSION

Assessment of SG score in women with previous CD using Davey score might help to predict pelvic adhesions status before planning a new surgery.

A laparovaginal strategy to avoid bladder injury during laparoscopic-assisted vaginal hysterectomy in cases with ventrofixed uterus following previous cesarean section

Background

Laparoscopic hysterectomy for benign indications in cases with ventrofixed uterus following previous cesarean section (CS) increases the surgeon’s concern of bladder injury. The present study describes a laparovaginal strategy to avoid bladder injury during laparoscopic-assisted vaginal hysterectomy (LAVH) in cases with ventrofixed uterus following previous CS.

Methods

In a retrospective study conducted in our private general hospital, we included consecutive cases of laparoscopically confirmed ventrofixed uterus associated with previous CS. These were from the cases who underwent LAVH for benign indications. Cases with uterus size >16 weeks of gestation were excluded. Patients’ clinical, intraoperative and postoperative characteristics were studied to evaluate the feasibility of the described laparovaginal strategy to prevent bladder injury during LAVH in cases with ventrofixed uterus.

Results

A total of 35 cases with ventrofixed uterus underwent LAVH during the study. Six (17.14%) cases had a history of one CS, while 29 (82.86%) cases had a history of previous two or more CSs. A supravesical loose fatty tissue plane (supravesical space) indicating reach to the bladder wall during laparoscopic lysis of the uterus from the anterior abdominal wall was successfully demonstrated in all the cases. The bladder flap preparation was avoided. Uterovesical adhesions were dissected by posteroanterior approach during vaginal phase of LAVH in all the cases. LAVH was successfully performed in all the cases. None of the cases had bladder injury, laparotomic conversion or other major complications. Mean operating time for LAVH was 149.71±38.36 minutes (70–200 minutes). Mean uterine specimen weight was 162.85±92.57 g (60–500 g). Mean postoperative hospital stay was 2.42±0.73 days (2–5 days).

Conclusion

In spite of severe adhesions in cases with a ventrofixed uterus following previous CS, bladder injury can be avoided during LAVH by the described laparovaginal approach in the present study.

Short synopsis

The described laparovaginal approach may avoid bladder injury during laparoscopic-assisted vaginal hysterectomy in cases with a ventrofixed uterus following previous cesarean section.

Evaluation of the diagnostic potential of trans abdominal ultrasonography in detecting intra-abdominal adhesions: A double-blinded cohort study

Background

Intra-abdominal adhesion is one of the most important complications of abdominopelvic surgery. It increases morbidity and mortality for patients. Although laparoscopy is the gold standard of adhesion diagnosis, it can cause visceral damage during the operation. Therefore, surgeons prefer to use non-invasive methods for planning the operation. We designed this study to evaluate transabdominal ultrasonography ( TAU) accuracy for diagnosing Intra-abdominal Adhesions

Material & methods

This double-blinded cohort study was conducted on 47 patients with previous laparotomy who undergo another surgery. Spontaneous visceral slide (SVS) and induced visceral slide (IVS) were measured during TAU.

Results

The mean age and BMI of 47 patients were 43.21±10.3 and 27.545±5.76. The majority of the patients were female (76%). Mean SVS and IVS in patients with intra-abdominal adhesion were 8.73±1.60 and 44.84±11.60. Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV) and accuracy of TAU in intra-abdominal diagnosis were 83.33%, 51.72%, 51.72%, 83.33%, 63.83%.

Conclusions

Although TAU is an appropriate method for detecting the intra-abdominal adhesion, it isn't good enough for diagnosing free adhesion area. We recommended further researches with greater sample size and other non-invasive techniques.

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Evaluation of accuracy, sensitivity, specificity, PPV, NPV for adhesion diagnosis.

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There are not a lot of studies on ultrasonography accuracy before.

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It’s an only double-blinded cohort study.

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Our study refers to high sensitivity and NPV for diagnosing the adhesion.

Transabdominal ultrasound: Can it be used to detect and quantify adhesions/reported pain, following Caesarean section?

BACKGROUND

Caesarean section is common in the UK with post-procedural adhesions causing life-long clinical symptoms and impacting future pregnancies. This study's aim was to explore associations between these surgical adhesions, via transabdominal ultrasound findings, and perceived symptoms.

METHOD

Females demonstrating 1-3 transverse, lower-segment Caesareans were included. Visceral slide transabdominal ultrasound elicited positive adhesions (<1 cm movement) and negative adhesions (>1 cm movement). Scar tissue quality was assessed by the Patient and Observer Scar Assessment Scale (POSAS) and Numerical rating scales (NRS) described pain symptoms. The relationship between adhesions was explored using Fisher's exact test and multiple regression analysis.

RESULTS

Twenty-two subjects (mean-age 35) were recruited; twenty participants (91%) had undergone 1 Caesarean, one each of the remainder had undergone 2 and 3 Caesareans respectively. Increased Visceral slide (>1 cm) was seen as predictive of increased scar pain (R² = 0.76 (95% CI 0.12-0.28), P < 0.001).

CONCLUSION

Caesarean adhesion scans showed significant associations with pain symptomology. Comprehensive adhesion assessment needs to be developed to improve long term outcomes of adhesions. Transabdominal Ultrasound can be considered a useful, quick and non-deleterious alternative diagnostic tool to Laparoscopy, therefore preventing further adhesion formation.

Hyaluronic acid-carboxymethylcellulose reduced postoperative bowel adhesions following laparoscopic urologic pelvic surgery: a prospective, randomized, controlled, single-blind study

BACKGROUND

To assess the anti-adhesive effect of treatment with hyaluronic acid-carboxymethylcellulose following laparoscopic radical prostatectomy.

METHODS

This was a randomized, controlled, single-blind, parallel-group study using hyaluronic acid-carboxymethylcellulose in patients who underwent laparoscopic radical prostatectomy. Sixty patients were enrolled in the study. All patients were randomly assigned to either the hyaluronic acid-carboxymethylcellulose treatment group (n = 30) or the control group (n = 30). Viscera slide ultrasounds and plain X-rays were obtained at enrollment (V0), postoperative week 12 (V1), and 24 (V2). The primary end point was the difference in the excursion distance in the viscera slide ultrasound between V0 and V2.

RESULTS

A total of 50 patients completed this study. The average excursion distance at V2 in the experimental group (n = 25) was significantly longer than in the control group (n = 25, 2.7 ± 1.2 vs. 1.3 ± 1.0 cm, respectively; p < 0.001). The differences in the V0 and V2 excursion distances were significantly higher in the control group than in the experimental group (1.48 ± 1.5 vs. 2.9 ± 1.2 cm, respectively; p < 0.001). None of patients showed adverse events associated with the use of hyaluronic acid-carboxymethylcellulose.

CONCLUSION

This randomized study demonstrated that hyaluronic acid-carboxymethylcellulose treatment resulted in a reduction in bowel adhesion to the abdominal wall after laparoscopic pelvic surgery and had good clinical safety.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: NCT02773251 Date: May 12, 2016.

Role of Minimally Invasive Surgery in the Reoperative Abdomen or Pelvis

Laparoscopy has become widely accepted as the preferred surgical approach in the management of benign and malignant colorectal diseases. Once considered a relative contraindication in patients with prior abdominal surgery (PAS), as surgeons have continued to gain expertise in advanced laparoscopy, minimally invasive approaches have been increasingly incorporated in the reoperative abdomen and pelvis. Although earlier studies have described conversion rates, most contemporary series evaluating the impact of PAS in laparoscopic colorectal resection have reported equivalent conversion and morbidity rates between reoperative and non-reoperative cases, and series evaluating the impact of laparoscopy in reoperative cases have demonstrated improved short-term outcomes with laparoscopy. The data overall highlight the importance of case selection, careful preoperative preparation and planning, and the critical role of surgeons' expertise in advanced laparoscopic techniques. Challenges to the widespread adoption of minimally invasive techniques in reoperative colorectal cases include the longer learning curve and longer operative time. However, with the steady increase in adoption of minimally invasive techniques worldwide, minimally invasive surgery (MIS) is likely to continue to be applied in the management of increasingly complex reoperative colorectal cases in an effort to improve patient outcomes. In the hands of experienced MIS surgeons and in carefully selected cases, laparoscopy is both safe and efficacious for reoperative procedures in the abdomen and pelvis, with measurable short-term benefits.

A Novel Diagnostic Aid for Detection of Intra-Abdominal Adhesions to the Anterior Abdominal Wall Using Dynamic Magnetic Resonance Imaging

Introduction. Abdominal adhesions can cause serious morbidity and complicate subsequent operations. Their diagnosis is often one of exclusion due to a lack of a reliable, non-invasive diagnostic technique. Development and testing of a candidate technique are described below. Method. During respiration, smooth visceral sliding motion occurs between the abdominal contents and the walls of the abdominal cavity. We describe a technique involving image segmentation and registration to calculate shear as an analogue for visceral slide based on the tracking of structures throughout the respiratory cycle. The presence of an adhesion is attributed to a resistance to visceral slide resulting in a discernible reduction in shear. The abdominal movement due to respiration is captured in sagittal dynamic MR images. Results. Clinical images were selected for analysis, including a patient with a surgically confirmed adhesion. Discernible reduction in shear was observed at the location of the adhesion while a consistent, gradually changing shear was observed in the healthy volunteers. Conclusion. The technique and its validation show encouraging results for adhesion detection but a larger study is now required to confirm its potential.

Trocar in conventional laparoscopic and robotic-assisted surgery as a major cause of iatrogenic trauma to the patient

All laparoscopic procedures, laparoscopic or robotic-assisted, start with a trocar entry. Unfortunately unknown to most, this is an extremely important part of the surgery, as 80% of major vascular injuries and 50% of intestinal injuries occur during this procedure. Laparoscopic first entry is often delegated to trainees with little experience, wrongly assuming that laparoscopic entry is similar to incisional entry at laparotomy. This may result in patient death (mortality of major vascular injuries is 11% and unrecognized intestinal injuries is 5%) or significant temporary or permanent morbidity.

Adhesions to Mesh after Ventral Hernia Mesh Repair Are Detected by MRI but Are Not a Cause of Long Term Chronic Abdominal Pain

Aim. The aim of the present study was to perform MRI in patients after ventral hernia mesh repair, in order to evaluate MRI's ability to detect intra-abdominal adhesions. Materials and Methods. Single-center long term follow-up study of 155 patients operated for ventral hernia with laparoscopic (LVHR) or open mesh repair (OVHR), including analyzing medical records, clinical investigation with patient-reported pain (VAS-scale), and MRI. MRI was performed in 124 patients: 114 patients (74%) after follow-up, and 10 patients referred for late complaints after ventral mesh repair. To verify the MRI-diagnosis of adhesions, laparoscopy was performed after MRI in a cohort of 20 patients. Results. MRI detected adhesions between bowel and abdominal wall/mesh in 60% of the patients and mesh shrinkage in 20-50%. Adhesions were demonstrated to all types of meshes after both LVHR and OVHR with a sensitivity of 70%, specificity of 75%, positive predictive value of 78%, and negative predictive value of 67%. Independent predictors for formation of adhesions were mesh area as determined by MRI and Charlson index. The presence of adhesions was not associated with more pain. Conclusion. MRI can detect adhesions between bowel and abdominal wall in a fair reliable way. Adhesions are formed both after open and laparoscopic hernia mesh repair and are not associated with chronic pain.

Imaging visceral adhesion to polymeric mesh using pneumoperitoneal-MRI in an experimental rat model

BACKGROUND

Intraperitoneal mesh implantation is often associated with formation of adhesion to the mesh. This experimental study examines the potential of minimally invasive pneumoperitoneal-MRI to assess these adhesions in a preclinical context.

METHODS

Uncoated polyethylene terephthalate meshes were placed intraperitoneally in rats, in regard to the caecum previously scraped to promote petechial bleeding and subsequent adhesions. Examinations were performed 2-weeks post mesh implantation using a rodent dedicated high field MRI. Respiratory-triggered T2-weighted images were acquired prior to and after intraperitoneal injection of ~8-10 mL gas to induce a mechanical stress on the abdominal wall.

RESULTS

Adhesions are occasionally seen in sham-operated rats as opposed to rats receiving polyethylene terephthalate meshes. On high-resolution images, meshes can be detected due to their characteristic net shape. However, evidence of adherence is only found if intraperitoneal gas injection is performed, when a ~1-cm elevation of the abdominal wall is observed. When adherence occurs between the mesh and the caecum, the latter remains in contact with the wall. Looser adherences between visceral tissue and meshes are also observed.

CONCLUSIONS

T2-weighted pneumoperitoneal-MRI is a powerful tool for assessing adherence after intraperitoneal mesh implantation. According to the mini-invasive procedure adopted here, this approach may allow a temporal follow-up of adherence fate.

Preoperative nomogram to predict risk of bowel injury during adhesiolysis

BACKGROUND

Inadvertent bowel injury during adhesiolysis is a major cause of increased morbidity and mortality following abdominal surgery. Identification of risk factors predicting this complication would guide preoperative counselling and surgical decision-making. The aim of this study was to identify predictive preoperative factors for inadvertent bowel injury occurring during adhesiolysis.

METHODS

All patients undergoing elective abdominal surgery between June 2008 and June 2010 were evaluated prospectively as part of the LAPAD study. Data on adhesiolysis and inadvertent organ injury were gathered by direct observation during operation. Univariable logistic regression was used to investigate factors that increased the risk of inadvertent bowel injury. Independent predictors of bowel injury were identified using multivariable logistic regression and used to create a clinical nomogram.

RESULTS

Of 715 patients eligible for analysis, 48 (6.7 per cent) had inadvertent bowel injuries. In 42 patients the defect was detected during operation and in nine at a later time (3 patients had both). Bowel resection was required for almost two-thirds of the enterotomies. The number of previous laparotomies, anatomical site of the operation, presence of bowel fistula and laparotomy via a pre-existing median scar were independent predictors of bowel injury. A clinical scoring system was constructed using a nomogram incorporating these risk factors; this had a predictive discrimination, measured as the area under the receiver operating characteristic curve, of 0.85.

CONCLUSION

A nomogram based on four independent factors predicted the risk of inadvertent bowel injury.

REGISTRATION NUMBER

NCT01236625 (http://www.clinicaltrials.gov).

Laparoscopic common bile duct exploration in patients with previous upper abdominal operations

Backgrounds/Aims

We aimed to to evaluate the feasibility of laparoscopic common bile duct exploration (LCBDE) in patients with previous upper abdominal surgery.

Methods

Retrospective analysis was performed on data from the attempted laparoscopic common bile duct exploration in 44 patients. Among them, 5 patients with previous lower abdominal operation were excluded. 39 patients were divided into two groups according to presence of previous upper abdominal operation; Group A: patients without history of abdominal operation. (n=27), Group B: patients with history of upper abdominal operation. Both groups (n=12) were compared to each other, with respect to clinical characteristics, operation time, postoperative hospital stay, open conversion rate, postoperative complication, duct clearance and mortality.

Results

All of the 39 patients received laparoscopic common bile duct exploration and choledochotomy with T-tube drainage (n=38 [97.4%]) or with primary closure (n=1). These two groups were not statistically different in gender, mean age and presence of co-morbidity, mean operation time (164.5±63.1 min in group A and 134.8±45.2 min in group B, p=0.18) and postoperative hospital stay (12.6±5.7 days in group A and 9.8±2.9 days in group B, p=0.158). Duct clearance and complication rates were comparable (p>0.05). 4 cases were converted to open in group A and 1 case in group B respectively. In group A (4 of 27 (14.8%) and 1 of 12 (8.3%) in group B, p=0.312) Trocar or Veress needle related complication did not occur in either group.

Conclusions

LCBDE appears to be a safe and effective treatment even in the patients with previous upper abdominal operation if performed by experienced laparoscopic surgeon, and it can be the best alternative to failed endoscopic retrograde cholangiopancreatography for difficult cholelithiasis.

In vivo MRI visualization of mesh shrinkage using surgical implants loaded with superparamagnetic iron oxides

BACKGROUND

Prosthetic mesh implants are widely used in hernia surgery. To show long-term mesh-related complications such as shrinkage or adhesions, a precise visualization of meshes and their vicinity in vivo is important. By supplementing mesh fibers with ferro particles, magnetic resonance imaging (MRI) can help to delineate the mesh itself. This study aimed to demonstrate and quantify time-dependent mesh shrinkage in vivo by MRI.

METHODS

Polyvinylidenfluoride (PVDF) meshes with incorporated superparamagnetic iron oxides (SPIOs) were implanted as an abdominal wall replacement in 30 rats. On days 1, 7, 14, or 21, MRI was performed using a gradient echo sequence with repetition time (TR)/echo time (TE) of 50/4.6 and a flip angle of 20°. The length, width, and area of the device were measured on axial, coronal, and sagittal images, and geometric deformations were assessed by surgical explantation.

RESULTS

In all cases, the meshes were visualized and their area estimated by measuring the length and width of the mesh. The MRI presented a mean area shrinkage in vivo of 13% on day 7, 23% on day 14, and 23% on day 21. Postmortem measurements differed statistically from MRI, with a mean area shrinkage of 23% on day 7, 28% on day 14, and 30% on day 21. Ex vivo measurements of shrinkage showed in vivo measurements to be overestimated approximately 8%. Delineation of the mesh helped to show folding or adhesions close to the intestine.

CONCLUSION

Loading of surgical meshes with SPIOs allows their precise visualization during MRI and guarantees an accurate in vivo assessment of their shrinkage. The authors' observation clearly indicates that shrinkage in vivo is remarkably less than that shown by illustrated explantation measurements. The use of MRI with such meshes could be a reliable technique for checking on proper operation of implanted meshes and showing related complications, obviating the need for exploratory open surgical revision.

Functional cine MRI and transabdominal ultrasonography for the assessment of adhesions to implanted synthetic mesh 5-7 years after laparoscopic ventral hernia repair

BACKGROUND

Laparoscopic ventral hernia repair (LVHR) has gained worldwide acceptance, due to its minimally invasive character, feasibility and low rate of complications. Animal experiments have shown marked adhesions to the intraperitoneal mesh (IPM), the clinical consequences being unclear. This study aimed to describe the extension of adhesions to the mesh, 5-7 years after LVHR, using two validated non-invasive radiologic methods.

METHODS

Real-time transabdominal ultrasonography (TAU) and cine magnetic resonance imaging (MRI) was applied to 30 patients with prior LVHR and implantation of IPM (Intramesh W3, Cousin Biotech, France). The visceral slide was measured in nine predefined abdominal segments. Values <or=1 cm were defined as an area with adhesion.

RESULTS

The mean time between LVHR and TAU/cine MRI was 67 months (range, 58-80 months). We found adhesion to the mesh in 90% of the patients using TAU and 100% of the patients using cine MRI. In the latter, 65% were between the bowel and IPM.

CONCLUSIONS

LVHR is known to reduce recurrences and postoperative complications, while improving patient outcome. The intraperitoneal placement of the mesh has been shown to induce adhesions; the amount and extension in the clinical setting is unclear. The present study showed a marked proportion of adhesions to the mesh with an average surgery to scan time of 5.6 years, despite an anti-adhesive barrier on the visceral surface of the mesh. Together with existing data, this result increases the concern related to the long-term consequences of an IPM. As a consequence, a comprehensive and comparable test system for medical devices, i.e. IPM, is needed.