A gross abdominal wall hematoma secondary to transversus abdominis plane block.

We aimed to share our experience with an abdominal wall hematoma that developed after an ultrasonography-guided TAP block performed for the palliation of chronic abdominal wall pain. Bleeding was successfully stopped with coil embolization.

Anthropometric parameters as a predictor for abdominal wall thickness in a patient with gastrostomy.

BACKGROUND: Enteral feeding tubes play essential roles in clinical management and nutritional support. Knowledge of the abdominal wall is beneficial in surgical practice and safe for gastrostomy. Anthropometric parameters are currently used for clinical assessment in many clinical applications. That might be beneficial if we applied anthropometric measurement for thickness prediction of the abdominal wall to the schedule of patients' gastrostomy care. This study aimed to evaluate the anthropometric parameters of abdominal wall thickness (AWT). METHODS: We conducted a cross-sectional study with anthropometric parameters and CT-measured anterior AWT were assessed and analyzed. RESULTS: The data are collected from January 2020 to March 2021. Arm circumference and body mass index were strongly correlated with AWT at left upper quadrant area and anterior AWT at middle area. The data was created in an TAWT (Thammasat AWT) chart to represent body parameters to AWT. CONCLUSIONS: Arm circumference is related to AWT. A TAWT chart is designed to help medical personnel evaluate the thickness of the abdominal wall and could guide estimating the gastrostomy tube length.

Linea alba 3D morphometric variability by CT scan exploration.

PURPOSE: The width of the Linea alba, which is often gauged by inter-rectus distance, is a key risk factor for incisional hernia and recurrence. Previous studies provided limited descriptions with no consideration for width, location variability, or curvature. We aimed to offer a comprehensive 3D anatomical analysis of the Linea alba, emphasizing its variations across diverse demographics. METHODS: Using open source software, 2D sagittal plane and 3D reconstructions were performed on 117 patients' CT scans. Linea alba length, curvature assessed by the sagitta (the longest perpendicular segment between xipho-pubic line and the Linea alba), and continuous width along the height were measured. RESULTS: The Linea alba had a rhombus shape, with a maximum width at the umbilicus of 4.4 ± 1.9 cm and a larger width above the umbilicus than below. Its length was 37.5 ± 3.6 cm, which increased with body mass index (BMI) (p < 0.001), and was shorter in women (p < 0.001). The sagitta was 2.6 ± 2.2 cm, three times higher in the obese group (p < 0.001), majorated with age (p = 0.009), but was independent of gender (p = 0.212). Linea alba width increased with both age and BMI (p < 0.001-p = 0.002), being notably wider in women halfway between the umbilicus and pubis (p = 0.007). CONCLUSION: This study provides an exhaustive 3D description of Linea alba's anatomical variability, presenting new considerations for curvature. This method provides a patient-specific anatomy description of the Linea alba. Further studies are needed to determine whether 3D reconstruction correlates with pathologies, such as hernias and diastasis recti.

Preoperative CT imaging as a tool to predict incisional hernia outcomes following abdominal wall reconstruction: A retrospective cohort analysis.

INTRODUCTION: Ventral wall hernia often causes significant morbidity and requires complex abdominal wall reconstruction (AWR). This study aims to determine whether subcutaneous abdominal fat thickness (AFT) measured with preoperative CT scans could predict postoperative outcomes in patients undergoing AWR. METHODS: A retrospective cohort study was conducted on all patients who underwent AWR at our institution between 2009 and 2021, with a minimum follow-up of 12 months. Using preoperative CT scans, AFT was measured at the xiphoid process, umbilicus, and pubic tubercle, as well as the hernia dimensions. Demographic, operative, and surgical outcome data were also collected and analyzed using statistical tests. RESULTS: The results showed that 9 of 101 patients (8.9%) experienced hernia recurrence. Smoking was associated with an increased risk of hernia recurrence (p < 0.001) with a predictive odds ratio (OR) of 18.27 (p = 0.041). Increased AFT at the xiphoid (p = 0.005), umbilicus (p < 0.001), and pubic tubercle (p < 0.001) were also associated with hernia recurrence and risk of infection. Only AFT at the pubic tubercle reached significance in the regression model predicting recurrence (OR=1.10; p = 0.030) and infection (OR=1.04; p = 0.021). A cut-off value of 67 mm was associated with a positive predictive value of 42.14% (sensitivity of 67% and specificity of 91%). Hernia defect area was not associated with risk of recurrence or infection. CONCLUSIONS: Smoking and increased AFT at the pubic tubercle are significant predictive factors for recurrence and infection in patients undergoing AWR, and preoperative optimization should focus on reducing these factors.

Volumetry after botulinum toxin A: the impact on abdominal wall compliance and endotracheal pressure.

PURPOSE: Botulinum toxin type A (BTA) is an adjuvant tool used in the preoperative optimization of complex hernias before abdominal wall reconstruction (AWR). This study aims to investigate changes in the abdominal cavity and hernia sac dimensions after BTA application. METHOD: A prospective study with 27 patients with a hernia defect of ≥ 10 cm and loss of domain (LOD) ≥ 20% underwent AWR. Computed tomography (CT) measurements and volumetry before and after the application of BTA were performed. Intraoperative and postoperative outcomes were evaluated. RESULTS: Imaging post-BTA revealed hernia width reduction of 1.9 cm (p = 0.002), lateral abdominal wall muscle elongation of 3.1 cm (p < 0.001), hernia volume reduction (HV) from 2.9 ± 0.9L to 2.4 ± 0.8L (p < 0.001), increase in abdominal cavity volume (ACV) from 9.7 ± 2.5L to 10.3L ± 2.4L (p = 0.003), and a reduction in the HV/ACV ratio from 30.2 ± 5% to 23.4 ± 6% (p < 0.001). Fascial closure was achieved in 92.6% of cases and component separation was required in 78%. The average variation in pulmonary plateau pressure was 3.53 cmH2O, and there were no postoperative respiratory failure recorded. At the 90-day follow-up, the wound morbidity rate was 25%, unplanned readmissions were 11%, and hernia recurrence 7.4%. CONCLUSION: BTA produces measurable volumetric changes in abdominal wall and appears to facilitate fascial closure. Further studies are required to determine the role of BTA in the surgical armamentarium for complex hernia repair.

Abdominal Wall Endometriosis at the Cesarean Section Scar.

Abdominal wall endometriosis is atypical localization of the extra-pelvic endometriosis with non-specific symptoms and is difficult for diagnosis. Cesarean scar endometriosis (CSE) is the most common type of abdominal wall endometriosis, which usually develops after obstetric operations. We report a case of a 33-year-old woman who had two previous cesarean sections presented with a mass in the subcutaneous tissue of the abdominal wall, approximately 4 cm superior to the Pfannenstiel incision, 5 years after her second lower segment caesarean section. The classic clinical presentation, imaging findings on ultrasonography and computed tomography are analyzed. Treatment with local surgical excision of the mass is discussed. The diagnosis was confirmed with histopathological analysis of the surgical sample. When it comes to the limited painful lesion in the subcutaneous tissue at the cesarean scar, with a pain intensifying during menstruation, the physician should consider cesarean scar endometriosis in women of reproductive age with a history of cesarean section.

The effect of breathing on the in vivo mechanical characterization of linea alba by ultrasound shearwave elastography.

The most common surgical repair of abdominal wall hernia consists in implanting a mesh to reinforce hernia defects during the healing phase. Ultrasound shearwave elastography (SWE) is a promising non-invasive method to estimate soft tissue mechanical properties at bedside through shear wave speed (SWS) measurement. Combined with conventional ultrasonography, it could help the clinician plan surgery. In this work, a novel protocol is proposed to reliably assess the stiffness of the linea alba, and to evaluate the effect of breathing and of inflating the abdomen on SWS. Fifteen healthy adults were included. SWS was measured in the linea alba, in the longitudinal and transverse direction, during several breathing cycle and during active abdominal inflation. SWS during normal breathing was 2.3 [2.0; 2.5] m/s in longitudinal direction and 2.2 [1.9; 2.7] m/s in the transversal. Inflating the abdomen increased SWS both in longitudinal and transversal direction (3.5 [2.8; 5.8] m/s and 5.2 [3.0; 6.0] m/s, respectively). The novel protocol significantly improved the reproducibility relative to the literature (8% in the longitudinal direction and 14% in the transverse one). Breathing had a mild effect on SWS, and accounting for it only marginally improved the reproducibility. This study proved the feasibility of the method, and its potential clinical interest. Further studies on larger cohort should focus on improving our understanding of the relationship between abdominal wall properties and clinical outcomes, but also provide a cartography of the abdominal wall, beyond the linea alba.

Robot-assisted Laparoscopic Excision of Abdominal Wall Endometrioma Utilizing Intraoperative Ultrasound and Transabdominal Needle Placement.

OBJECTIVE: In patients with endometriosis, extra pelvic endometriosis is estimated to have an incidence of 11% and a rare subset of extra pelvic lesions include abdominal wall endometriosis with an incidence of 0.03% to 3.5% [1,2]. Evaluation for and surgical management of abdominal wall endometriosis are an essential skill set for the advanced gynecologic surgeon. In this video, we demonstrate a surgical technique for robot-assisted laparoscopic excision of abdominal wall endometriosis with intraoperative ultrasound-guided needle placement. DESIGN: Description and demonstration of surgical technique. SETTING: A patient with previous history of 2 cesarean sections and right lower quadrant cyclic abdominal wall pain; a tertiary care, academic center. INTERVENTIONS: Intraoperative ultrasound-guided needle placement to map location and boundaries of the lesion followed by minimally invasive resection of the lesion with the intermittent advancement and withdrawal of needles to confirm clear margins. CONCLUSION: Minimally invasive resection of abdominal wall endometriosis using intraoperative ultrasound-guided needle placement is an effective technique to guide surgical dissection and allow for clear surgical margins and successful treatment of this rare condition.

The prominent role of percutaneous transarterial embolization in the treatment of anterior abdominal wall hematomas: the results of three high volume tertiary referral centers.

PURPOSE: Percutaneous transarterial embolization (PTE) represents a fast, safe and effective option for life-threatening anterior abdominal wall hematomas (AWHs) and those unresponsive to conservative treatment. Our study aims to assess cumulative results of safety, technical and clinical success of PTE performed in three high-volume tertiary referral centers and to evaluate the efficacy of the different embolic materials employed. MATERIALS AND METHODS: A consecutive series of 124 patients (72.8 ± 14.4 years) with AWHs of different etiology submitted to PTE were retrospectively collected and analyzed. Clinical success, defined as absence of recurrent bleeding within 96 h from PTE, was considered as primary endpoint. The results of the comparison of three groups based on embolic agent employed were also analyzed. RESULTS: Spontaneous AWHs accounted for 62.1%, iatrogenic for 21.8% and post-traumatic for 16.1% of cases. SARS-CoV-19 infection was present in 22.6% of patients. The most commonly embolized vessels were epigastric inferior artery (n = 127) and superior epigastric artery (n = 25). Technical and clinical success were 97.6 and 87.1%, respectively. Angiographic signs of active bleeding were detected in 85.5% of cases. Four (4%) major complications were reported. The comparison of the three groups of embolic agents (mechanical, particulate/fluid and combined) showed no statistically significant differences in terms of clinical success. SARS-CoV-2 infection was found to be an independent factor for recurrent bleeding and poor 30-day survival. CONCLUSION: PTE performed with all the embolic agent employed in our centers is a safe and effective tool in the treatment of life-threatening anterior AWH of each origin.

Percutaneous Imaging-guided Cryoablation of Endometriosis Scars of the Anterior Abdominal Wall.

STUDY OBJECTIVE: To evaluate the safety and clinical efficacy of percutaneous imaging-guided cryoablation for the management of anterior abdominal wall endometriosis. DESIGN: Patients with abdominal wall endometriosis underwent percutaneous imaging-guided cryoablation and had a 6-month follow-up. SETTING: Data dealing with patients' and anterior abdominal wall endometriosis (AAWE) characteristics, cryoablation, and clinical and radiologic outcomes were retrospectively collected and analyzed. PATIENTS: Twenty-nine consecutive patients underwent cryoablation from June 2020 to September 2022. INTERVENTIONS: Interventions were performed under US/computed tomography (CT) guidance or magnetic resonance imaging (MRI) guidance. Cryoprobes were directly inserted into the AAWE, and cryoablation was performed with a single 5 to 10 minute freezing cycle, which was stopped when the iceball expanded 3 to 5 mm beyond AAWE borders as assessed on intra-procedural cross-sectional imaging. MEASUREMENTS AND MAIN RESULTS: Fifteen patients (15/29; 51.7%) had prior endometriosis, 28 (28/29; 95.5%) had previous cesarian section, and 22 (22/29; 75.9%) referred association between symptoms and menses. Cryoablation was performed under local (16/29; 55.2%) or general anesthesia (13/29; 44.8%) and mainly in an out-patient basis (18/20; 62%). There was only one (1/29; 3.5%) minor procedure-related complication. Complete symptom relief was recorded in 62.1% (18/29) and 72.4% (21/29) patients at 1 and 6 months, respectively. In the whole population, pain significantly dropped at 6 months compared to the baseline (1.1 ± 2.3; range 0-8 vs 7.1 ± 1.9; range 3-10; p <.05). Eight (8/29; 27.6%) patients presented residual symptoms at 6 months, and 4 (4/29; 13.8%) had an MRI-confirmed residual/recurring disease. Contrast-enhanced MRI obtained for the first 14 (14/29; 48.3%) patients of the series, all without signs of residual/recurring disease, demonstrated a significantly smaller ablation area compared to the baseline volume of the AAWE (1.0 cm3 ± 1.4; range 0-4.7; vs 11.1 ± 9.9 cm3; range 0.6-36.4; p <.05). CONCLUSION: Percutaneous imaging-guided cryoablation of AAWE is safe and clinically effective in achieving pain relief.

Correlation between abdominal visceral volume measured by a simple procedure and bulging at the abdominal free flap donor site for breast reconstruction.

BACKGROUND: Breast reconstructions using autologous abdominal tissue result in breasts with a natural shape and consistency. One of the major complications is abdominal bulging. Because of the increased abdominal wall tension, high visceral volume (not visceral fat alone) may increase the occurrence rate of abdominal bulging. A simple procedure involving CT imaging was used to assess this relationship in patients undergoing an abdominal free flap for unilateral breast reconstruction. METHODS: A total of 278 patients were enrolled in this study. The patients' demographics, the thicknesses of visceral volume were compared (Bulging (+) vs. Bulging (-)). Visceral volume was investigated based on the horizontal thickness, which was measured at the thickest part at the level of the umbilical fossa between both sides under the transverse abdominis muscles. RESULTS: Bulging (+) consisted of 39 patients (14.0%), whereas Bulging (-) included 239 patients. Patients with Bulging (+) were significantly older, had higher gestational history rate, and had thin rectus abdominis muscle. In terms of visceral volume, the Bulging (+) group had significantly higher horizontal thicknesses (median 233 mm vs. 219 mm, P < 0.001). No significant differences were observed with respect to other factors (age, BMI, history of laparotomy, and operative details). The multivariate logistic regression analysis revealed that the thickness of the rectus abdominis muscle, horizontal visceral volume, and gestational history were independently significant predictors. CONCLUSIONS: Not only the patients with thin rectus abdominis muscle but also patients with a thick horizontal visceral volume may have a higher risk of abdominal bulging.

Caesarean-section scar endometriosis (CSSE): clinical and imaging fundamentals of an underestimated entity.

Caesarean-section scar endometriosis (CSSE) is a form of extra-pelvic endometriosis developing through endometrial cell implantation anywhere along the route of a previous caesarean section (CS) surgery, including the skin, subcutaneous tissue, abdominal wall muscles, intraperitoneally, and the uterine scar itself. Synchronous intra-abdominal endometriosis is not a prerequisite. Given the rising prevalence of CS, CSSE may be underrepresented in the literature and occur more frequently than previously thought. Locating a painful soft-tissue mass-like lesion along the path of a previous CS scar is the most indicative sign that should initially alarm physicians towards suggesting CSSE, especially if symptoms are typical (cyclically reoccurring with menstruation). The detection of hyperintense (haemorrhagic) foci on T1 fat-saturated sequences will strongly support the diagnosis on magnetic resonance imaging (MRI), the most sensitive imaging method for CSSE assessment. A non-specific, contrast-enhancing, hypodense nodule with spiculate edges may be suggestive if the lesion was originally detected on computed tomography (CT). Although ultrasound is frequently the first imaging method used, the findings are non-specific; therefore, making it more useful for ruling out other differentials and for image-guided biopsy. In any case, histopathology provides the definitive diagnosis. Surgical excision is the mainstay of treatment; however, minimally invasive, percutaneous techniques have also been implemented successfully.

Three-Dimensional Ultrasound Evaluation of Lung Volume in Fetuses with Abdominal Wall Defect.

INTRODUCTION: Abdominal wall defects (AWDs) interfere with postnatal respiratory parameters. We aimed to evaluate lung volume (LV) in fetuses with AWD using three-dimensional (3D) ultrasound (US) and to correlate AWD with the type (omphalocele and gastroschisis) and size of the defect and neonatal morbidity and mortality. METHODS: This prospective observational study included 72 pregnant women with fetuses with AWD and a gestational age <25 weeks. The data on abdominal volume, 3D US LV, and herniated volume were acquired every 4 weeks up to 33 weeks. LV was compared with normal reference curves and correlated with abdominal and herniated volumes. RESULTS: Omphalocele (p < 0.001) and gastroschisis (p < 0.001) fetuses had smaller LV than normal fetuses. LV was positively correlated with abdominal volume (omphalocele, r = 0.86; gastroschisis, r = 0.88), whereas LV was negatively correlated with omphalocele-herniated volume/abdominal volume (p < 0.001, r = -0.51). LV was smaller in omphalocele fetuses that died (p = 0.002), were intubated (p = 0.02), or had secondary closure (p < 0.001). In gastroschisis, a smaller LV was observed in fetuses discharged using oxygen (p = 0.002). CONCLUSION: Fetuses with AWD had smaller 3D LV than normal fetuses. Fetal abdominal volume was inversely correlated with LV. In omphalocele fetuses, a smaller LV was associated with neonatal mortality and morbidity.

Dual-phase contrast-enhanced multislice computed tomography scans play a key role in the diagnosis of abdominal wall desmoid-type fibromatoses.

BACKGROUND: Abdominal wall desmoid-type fibromatoses (AWDF) are occasionally encountered in clinical work, but related CT reports are rare, and most cases were misdiagnosed as malignant tumors. OBJECTIVE: We aimed to determine the diagnostic value of multislice computed tomography (MSCT) in relation to the clinical diagnosis of AWDF. METHODS: The medical records of 14 patients whose pathology results provided initial confirmation of AWDF were reviewed, and data describing their clinical characteristics, tumors' MSCT characteristics, and the condition of the surrounding tissues were analyzed and summarized retrospectively. Intraobserver and interobserver reproducibilities were evaluated. RESULTS: AWDF tended to occur in women of childbearing age (24-32 years). They occurred more frequently during the first year following pregnancy. The mean disease duration was 5.64 ± 3.78 months. All isolated tumors were growing along the musculoaponeurotic layer, and their maximum diameters were between 32 and 76 mm. Tumors' capsules were incomplete, and although the tumors infiltrated the surrounding muscles, the surrounding fat tissue and vessels were not infiltrated. None of the patients' tumors showed cystic degeneration, calcification, necrosis, or peritumoral edema. The tumors had slightly lower densities on the pre-contrast enhancement scans and mild-to-moderate enhancement after contrast enhancement. All tumors contained ribbon-like structures, and approximately 65% of the tumors encircled vascular structures. CONCLUSION: Dual-phase contrast-enhanced MSCT scans were associated with a high level of diagnostic efficacy for AWDF. The abdominal wall masses grew along the musculoaponeurotic layer, which, together with the ribbon-like structures within the tumors, should prompt clinicians to consider the presence of AWDF.

CT-measured hernia parameters can predict component separation: a cross-sectional study from China.

PURPOSE: Currently, there are no reliable preoperative methods for predicting component separation (CS) during incisional hernia repair. By quantitatively measuring preoperative computed tomography (CT) imaging, we aimed to assess the value of hernia defect size, abdominal wall muscle quality, and hernia volume in predicting CS. METHODS: The data of 102 patients who underwent open Rives-Stoppa retro-muscular mesh repair for midline incisional hernia between January 2019 and March 2022 were retrospectively analyzed. The patients were divided into two groups: ''CS group'' patients who required CS to attempt fascial closure, and ''non-CS'' group patients who required only Rives-Stoppa retro-muscular release to achieve fascial closure. Hernia defect width, hernia defect angle, rectus width, abdominal wall muscle area and CT attenuation, hernia volume (HV), and abdominal cavity volume (ACV) were measured on CT images. The rectus width to defect width ratio (RDR), HV/ACV, and HV/peritoneal volume (PV; i.e., HV + ACV) were calculated. Differences between the indices of the two groups were compared. Logistic regression models were applied to analyze the relationships between the above CT parameters and CS. Receiver operator characteristic (ROC) curves were generated to evaluate the potential utility of CT parameters in predicting CS. RESULTS: Of the102 patients, 69 were in the non-CS group and 33 were in the CS group. Compared with the non-CS group, hernia defect width (P < 0.001), hernia defect angle (P < 0.001), and hernia volume (P < 0.001) were larger in the CS group, while RDR (P < 0.001) was smaller. The abdominal wall muscle area in the CS group was slightly greater than that in the non-CS group (P = 0.046), and there was no significant difference in the CT attenuation of the abdominal wall muscle between the two groups (P = 0.089). Multivariate logistic regression identified hernia defect width (OR 1.815, 95% CI 1.428-2.308, P < 0.001), RDR (OR 0.018, 95% CI 0.003-0.106, P < 0.001), hernia defect angle (OR 1.077, 95% CI 1.042-1.114, P < 0.001), hernia volume (OR 1.002, 95% CI 1.001-1.003, P < 0.001), and CT attenuation of abdominal wall muscle (OR 0.962, 95% CI 0.927-0.998, P = 0.037) as independent predictors of CS. Hernia defect width was the best predictor for CS, with a cut-off point of 9.2 cm and an area under the curve (AUC) of 0.890. The AUCs of RDR, hernia defect angle, hernia volume, and abdominal wall muscle CT attenuation were 0.843, 0.812, 0.747, and 0.572, respectively. CONCLUSION: Quantitative CT measurements are of great value for preoperative prediction of CS. Hernia defect size, hernia volume, and the CT attenuation of abdominal wall muscle are all preoperative predictive indicators of CS.

Beyond the abdominal and pelvic cavity: abdominal wall and spinal "Aunt Minnies".

Abdominal wall and spinal soft tissue findings are frequently encountered on CT or MR imaging of the abdomen and pelvis. Many of these entities have specific imaging findings, for which a definitive diagnosis can be made without the need for further work up. These abdominal wall and spinal findings may be diagnostically challenging for sub-specialized abdominal radiologists who are unfamiliar with their appearance and appropriate management. This review article describes and illustrates pathognomonic or characteristic abdominal wall and spinal pathologies, which reside outside the abdominopelvic cavity. The cases selected all have findings that allow a confident diagnosis without further imaging or intervention. The cases presented include myonecrosis, intramuscular abscess, myositis, iliopsoas bursitis, Morel-Lavallée lesion, hydrocele of canal of Nuck, Klippel Trenaunay Weber syndrome, neurofibroma with target sign, perineural cysts, filum terminale lipoma, calvarial bone flap, transverse rectus abdominis muscle (TRAM) flap, liposuction, and hidradenitis suppurativa, among others. Although not all-encompassing, this paper will help abdominal radiologists to accurately diagnose a variety of abdominal and pelvic extra-cavitary soft tissue pathologies by identifying key radiologic findings.

Systematic review and meta-analysis of the inter-recti distance on ultrasound measurement in nulliparas.

The objective is to evaluate the inter-recti distance on ultrasound measurement at different locations in healthy nulliparas. Electronic databases were searched for studies describing the inter-recti distance measured by ultrasound in healthy nulliparas. We excluded studies without descriptions of the measurement position or the condition of the abdominal wall. A meta-analysis was performed to evaluate the inter-recti distance on ultrasound measurement. Seven eligible studies with 295 healthy nulliparas were included. The location of the inter-recti distance measurement by ultrasound was not uniform. The pooled data divided the measurement locations into three areas. The meta-analytic summary values of the umbilical inter-recti distance of the nulliparas was 8.77 mm (6.56-10.99 mm), the distance at the epigastric area was 7.22 mm (2.76-11.68 mm), and that at the infraumbilical area was 4.09 mm (1.55-6.64 mm). The maximal reported inter-recti distance in healthy nulliparous women is smaller than 10 mm on ultrasound measurement at all locations and the range in the umbilical area is larger than that in the epigastric, infraumbilical areas. The values for the inter-recti distance reported in this systematic review can be used as the reference of feasible and desirable distance of the rectus muscles after rectus fascia plication. The limitation was that the methodological quality of the assessment in most studies was unclear or low.

Predicting rare outcomes in abdominal wall reconstruction using image-based deep learning models.

BACKGROUND: Deep learning models with imbalanced data sets are a challenge in the fields of artificial intelligence and surgery. The aim of this study was to develop and compare deep learning models that predict rare but devastating postoperative complications after abdominal wall reconstruction. METHODS: A prospectively maintained institutional database was used to identify abdominal wall reconstruction patients with preoperative computed tomography scans. Conventional deep learning models were developed using an 8-layer convolutional neural network and a 2-class training system (ie, learns negative and positive outcomes). Conventional deep learning models were compared to deep learning models that were developed using a generative adversarial network anomaly framework, which uses image augmentation and anomaly detection. The primary outcomes were receiver operating characteristic values for predicting mesh infection and pulmonary failure. RESULTS: Computed tomography scans from 510 patients were used with a total of 10,004 images. Mesh infection and pulmonary failure occurred in 3.7% and 5.6% of patients, respectively. The conventional deep learning models were less effective than generative adversarial network anomaly for predicting mesh infection (receiver operating characteristic 0.61 vs 0.73, P < .01) and pulmonary failure (receiver operating characteristic 0.59 vs 0.70, P < .01). Although the conventional deep learning models had higher accuracies/specificities for predicting mesh infection (0.93 vs 0.78, P < .01/.96 vs .78, P < .01) and pulmonary failure (0.88 vs 0.68, P < .01/.92 vs .67, P < .01), they were substantially compromised by decreased model sensitivity (0.25 vs 0.68, P < .01/.27 vs .73, P < .01). CONCLUSION: Compared to conventional deep learning models, generative adversarial network anomaly deep learning models showed improved performance on imbalanced data sets, predominantly by increasing model sensitivity. Understanding patients who are at risk for rare but devastating postoperative complications can improve risk stratification, resource utilization, and the consent process.

Imaging of the Abdominal Wall Sinus Tract: Comparison of Computed Tomography Sinography and X-Ray Sinography.

OBJECTIVE: The study aims to clarify the comparative benefits of X-ray sinography and computed tomography (CT) sinography in assessing the abdominal wall sinus tract. METHODS: In this cross-sectional study, patients in our hospital with an abdominal wall sinus tract who had received both X-ray sinography and CT sinography from January 2018 to January 2021 were enrolled. The intraoperative findings were used as the gold standard to calculate the accuracy of the two methods. Kappa statistic was employed to evaluate the concordance between the two methods and the intraoperative findings. Differences in diameters measured on X-ray sinography and CT sinography images were analyzed using the Wilcoxon signed rank test. RESULTS: The study sample consisted of 74 patients. The accuracy of the CT sinography in diagnosing the extent of the sinus invasion was 85.1%, while the accuracy of the X-ray sinography was 59.5%. For the sinus confined to the abdominal wall (Kappa: 0.783 VS 0.248), the sinus extending into the abdominal cavity (Kappa: 0.734 VS 0.339), and the sinus with fistula formation (Kappa: 0788 VS 0.496), the consistency of the CT sinography and surgery were significantly better than that of the X-ray sinography. Diameters of the sinus tract measured on CT images were statistically larger than the diameters measured on X-ray sinography (P<0.001). CONCLUSION: CT sinography has significant advantages to X-ray sinography in depicting the extent of the abdominal wall sinus tract and the presence of a fistula.

Transversus abdominis plane block in rats: Preliminary cadaveric studies.

The transversus abdominis plane (TAP) block is an ultrasound guided regional anaesthetic technique used to provide analgesia to the abdominal wall. Research in humans and cats has demonstrated that TAP blocks reduce pain and post-operative opioid requirements after abdominal surgery. To date TAP blocks have not been described in rats. The optimal technique to employ when performing TAP blocks is controversial with single point injection techniques failing to reliably provide adequate coverage of the cranial abdominal wall. It has been suggested that performing a two point injection may provide more reliable coverage of the cranial abdominal wall.The objective of this study was to determine the feasibility of performing ultrasound guided TAP blocks in rat cadavers and to evaluate whether performing a two point technique provides greater spread of injectate than a one point technique when administering the same total volume of methylene blue solution.Twenty-three, four-month-old, female Sprague Dawley rat cadavers weighing 506 ± 78 g were used. TAP blocks were performed using a total of 1 ml/kg of methylene blue solution.Overall success rates for injections were 21.7% (13.6-32.8%). Single point injection area of spread was 87.8 ± 32 mm2 compared with 102.4 ± 17 mm2 for the two point injection technique.Due to the low success rate the use of TAP blocks using the current technique cannot be recommended. Two point injection technique appears to provide greater spread; however, additional data is required to draw meaningful conclusions.